Discover the Latest Journals in Architecture and Architectonics
Architecture is both the process and product of planning, designing, and constructing a building or structure, while architectonics is the scientific study of architecture itself. Architectural works are often considered important cultural symbols and works of art, and we often identify past civilizations with their architectural heritage.
Architecture and Architectonics
Abstract
Contact with groundwater in the disposal geological site will induce the creation of an amorphous corrosion layer on the high-level radioactive glass. This is connected to silicate saturation conditions in the surrounding medium, and it is influenced significantly by geochemical processes in the near-field minerals at that depth. The international simple glass is a six-oxide borosilicate glass that is commonly used in nuclear interest. It is a simple glass generated from its composition to be an international benchmark glass. The results of the standard materials characterization center leaching tests in double deionized water at 90 °C and an initial pH value of 6.3 showed that it reacts with Ankerite for a short period of time. The effect of Ankerite on borosilicate glass durability through magnesium-silicate precipitation has been investigated and confirmed in this study.
Abstract
Visual identification of objects is an important challenge today. Main target of frequently applied methods is to identify or classify complex objects. These methods are far less effective when objects are small and less complex, and thus less descriptor features are on hand. The main reason for this is that these features can significantly change on object occlusion or appearance of noise.
The presented solution performs identification of simple, small (size is 17 × 13 pixels) objects with elliptical shape. High pass filtered normalized cross correlation is used for region of interest detection and a simple deep neural network is used for classification of selected regions. The proposed method detected objects on a noisy image with accuracy of 96.2%.
Abstract
The displacement of a loaded pile could be vertical (axial) or horizontal (lateral); these displacements are sensitive to groundwater presence within the soil mass. This paper presents a theoretical study to investigate vertical and horizontal displacement of piles embedded in a clayey soil for different levels of groundwater under the ground surface. The study was performed using the commercial finite element package PLAXIS-3D. Three diameters of the concrete piles were considered: 0.5, 0.75 and 1 m, and were subjected to 1,000 kN axial load. The effect of 0, 5, 10, 15 and 20 m groundwater along the 20 m pile in length from the ground surface on the vertical and horizontal displacements was investigated. The results indicated that the vertical and horizontal displacements increase when the ground water level increases towards the base of pile. Also, there is a significant increase in the horizontal displacement up to 15 m of groundwater level from ground surface and decreased at levels from 15 to 20 m.
Abstract
The reduction of energy consumption is a major issue nowadays that should be considered during the design process. High-rise buildings represent a building type with significantly high energy consumption. They serve typically as offices with fully glazed façades, generating considerable energy demand. This study aims to optimize the envelope and the shading systems of a high-rise office building (Middle Europe). For this purpose, multiple façade variants were tested by assessing the thermal and visual comfort, as well as energy demand. The IDA ICE 4.8 building energy simulation program was used for thermal and lighting modeling and to carry out building physics calculations. Results revealed the best performing, optimized façade configuration in terms of comfort and energy efficiency.
Abstract
The emerging popularity of telemedicine solutions brought an alarming problem due to the lack of proper access control solutions. With the inclusion of multi-tiered, heterogeneous infrastructures containing Internet of things and edge computing elements, the severity and complexity of the problem became even more alarming, calling for an established access control framework and methodology. The goal of the research is to define a possible solution with a focus on native cloud integration, possible deployment at multiple points along the path of the healthcare data, and adaptation of the fast healthcare interoperability resources standard. In this paper, the importance of this issue in offline use cases is presented and the effectiveness of the proposed solution is evaluated.
Abstract
This work, presents a novel optimizer called fertilization optimization algorithm, which is based on levy flight and random search within a search space. It is a biologically inspired algorithm by the fertilization of the egg in reproduction of mammals. The performance of the algorithm was compared with other optimization algorithms on CEC2015 time expensive benchmarks and large scale optimization problems. Remarkably, the fertilization optimization algorithm has overcome other optimizers in many cases and the examination and comparison results are encouraging to use the fertilization optimization algorithm in other possible applications.
Abstract
Telemedicine is one of the most rapidly developing areas of healthcare and it plays an increasing role in modern medicine. As the amount of data and demand for features increase, the data paths are becoming ever-more complex. Owing to this, it is vital in telemedicine to find a proper balance between consistency and availability under any given circumstances. However, making a trade-off can significantly influence the quality of the data. This study seeks to get an in-depth view of the problem by considering a real-world telemedicine use-case and elaborating the formal system specification of the scenario. After evaluating the specification, the constructed state graph is examined using graph coloring and other graph algorithms.
Abstract
Distinct technological trends seriously influence the modern software architectures. In this paper, four different software architectures and framework combinations were generally compared. The basis for the analysis is the developer's productivity.
In a 3 year-long research and development project, a real-world telemedicine application was efficiently implemented four times with various software architectures and architectural patterns. More than 5,000 person-hours were spent on carrying out them.
At present, a unique dataset is available, which provides the opportunity to compare the cost of spent person-hours in different approaches.
The goal of this research is to describe the measurement approach, the dataset and the applied architectures considering the software developer's productivity.
Abstract
Scours creation in riverbed at the Hričov weir is a permanent problem since its construction. It is caused by the shortened stilling basin of the weir. In almost all cases of flow control at the weir the energy is not dissipated sufficiently. A 3D physical model was built in the hydraulic laboratory to investigate the measures for reduction of the scour creation. To simulate uneven loads on the downstream riverbed, a flood discharge controlled by the weir in symmetric and asymmetric operations was used for simulations. The scours were evaluated using short-range photogrammetry for contactless measurements. Based on this method digital models of the riverbed for each simulation were created and the scours were assessed to determine the effect of the investigated measures on scour reduction.
Abstract
With the rise of the urban renewal motion in recent years in China, more and more cities have shifted the focus of construction to the renovation and renewal of old areas. The renewal of the old community plays an essential role in the urban upgrading of China, which is related to the quality of a city, as well as a crucial criterion for evaluating the comfort of the living environment. The old community to retain their vibrancy and culture is needed to renew by a way of modernization. The paper will discuss how to use micro-renewal design to improve the quality of the old community, awaking the historical memories of the community simultaneously, thereby balance the relationship between history and use-value.
Abstract
Imageability is the quality of a place that makes it distinct, recognizable, and memorable. It defines the character and identity for cities. However, the fast expansion of urban development affects the image of city and its fabric toward the mega scale and transforms cities local cultural life as loosing most of their historic fabrics. These make cities loose there images gradually. Hence, the aim of this paper is to explore the main physical elements that contribute toward attractiveness as one of imageability character in Salt City in Jordan. Historical review and site analysis were the main methodology used in this study. This paper show some of the physical elements that contribute to attractiveness connected with image of the Salt City in Jordan, these elements are: building appearance (material, façade design) and landscape (topography).
Abstract
Rapid development has affected the elements of urban spaces adversely, particularly streets. These changes produce faceless cities with high dependency on vehicles for transportation to key ‘consumers’ aside from buildings that are not designed for the local environment and local needs. In urban design, concerns on character affect the sense of place. Thus, this paper assesses the crucial element of streets with respect to design and character in the urban setting, the subsequent issues, and the recommended solution. This study focuses on the scenarios that threaten today's street design. This work will discuss the advantages of traditional streets, which could be a potential solution to the issues mentioned earlier. Finally, a street design based on the traditional street model is proposed to fulfill the criteria necessitated by the local community.
Abstract
Despite the clear benefits of maintaining a human relationship with nature, people increasingly live in urban settings. As a result of urbanization, numerous urban communities are confronting social and natural problems, which have genuinely compromised residents’ wellbeing and health. Thus, holistic planning and designing are needed to tackle these problems, integrating nature-based thinking into urban environmental development. The aim of this paper is to explore components of a sustainable city and biophilic design patterns and analyze the relationship between them. Finally, the conceptual model of a sustainable city has been proposed based on biophilic design approaches.
Abstract
In Hungary a lot of people live in condominiums or in block of flats where fire often occurs despite of precise design and effective fire protection arrangements. This means a hazard for the people living there, for the building constructions and also for the environment. A deeper knowledge of the burning process and examining the negative effects of fire load on building constructions with scientific methods are actual questions nowadays. In order to get to know the phenomena more accurately, fire spread in a bedroom was modeled and numerical simulation was carried out, which is presented in this paper in detail. These experiences may help increasing the fire safety and preventing fires in apartments. The simulations were carried out considering the characteristics of the Hungarian architecture.
Abstract
In order to develop the quality of urban spaces, street furniture seems to be the significant element that defines the city’s social attraction points. It stimulates outdoor spaces because of its location, buildings and sidewalk meet. This study explores the issues of design criteria that introduce sustainability into street furniture design in urban public space in Tunisia. This research is based on the role of street furniture and its importance in urban public spaces, and the possibility of supplementing a recycling design. This paper aims to explore the necessary criteria to design sustainable street furniture in order to present its importance in a way that helps to ameliorate the quality of living in urban areas and cities.
Abstract
Bitumen is a critical component in asphaltic pavements and is often the cause of many road failures. The commercial modifiers that are being used to enhance the properties of bitumen are quite expensive; therefore, this article is dedicated to explore the potential of local crumb rubber as bitumen modifier. Two grades of bitumen pen grade (60/70 and 80/100) were modified with local crumb rubber. Rheological properties of modified and unmodified bitumen were evaluated using Dynamic Shear Rheometer. The results indicated an increase in the rutting resistance of bitumen. This indicates that Local crumb rubber can be used to enhance the properties of bitumen.
Abstract
In watershed modeling research, it is practical to subdivide a watershed into smaller units or sub-watersheds for modeling purposes. The ability of a model to simulate the watershed system depends on how well watershed processes are represented by the model and how well the watershed system is described by model input. This study is conducted to evaluate the impact of watershed subdivision and different weather input datasets on streamflow simulations using the soil and water assessment tool model. For this purpose, Cuhai-Bakonyér watershed was chosen as a study area. Two climate databases and four subdivision variations levels were evaluated. The model streamflow predictions slightly effected by subdivision impact. The climate datasets showed significant differences in streamflow predictions.
Abstract
Present paper focuses on the modeling of size effect on the compressive strength of normal strength concrete with the application of discrete element method, considering specimen of different concrete mixes and shapes. An equation was derived to estimate the parallel bond strength from the compressive strength. The results showed a good agreement with the literature and the derived estimation models showed strong correlation with the measurements. The results indicated that size effect is stronger on concretes with lower strength class and that it is more significant on cube specimens than on cylinders. The relationship of model size and computational time was analyzed and a method to decrease the computational time (iterations) was proposed.
Abstract
With the development of economic globalization and the information age, architecture has gradually become a kind of seal of politics, capital and culture, and is divorced from the spirit and life experience of the existing places in the region. Therefore, the field of architecture constantly seeks new research paradigm from the interdisciplinary perspective and reconsiders the creative activities of architecture. From the late last century, with the introduction of architecture by postmodern philosophy, semiotics, geographical psychology, phenomenology and cultural anthropology, there has been a cross-research between architecture and narratology. The recent research hopes to conduct an in-depth analysis of the theory of architectural spatial narrative and its development in the context of complex disciplines, and to research spatial narrative as a design methodology for architecture.
Abstract
Supply chain management intends to integrate supply chains' activities such as material flow, information flow and financial issues. Material flow management is the most significant issue since the inventory level in the whole supply chain could be optimized by an integrated plan. In other words, when one member of the supply chain plans to reduce its inventory level solely, despite reducing inventory in this node the inventory will be stocked in other partners' warehouses. Therefore, in this paper a new mathematical model has been developed to facilitate the process of finding the optimum solution in economic production, purchase and delivery lots and their schedules in a three-echelon supply chain environment; including raw material in suppliers, manufacturer and assembly facility as a customer. The manufacturer with a flow shop system provides its requirements from supplier, assemble multiple products, and delivers products to the customer (automotive OEM alike) on an optimum multiple delivery points. The delivery cycles would be identified through the production common cycle regarding the supply chain flexibility. Finally, a modified real-valued Genetic Algorithm (MRGA), and an Optimal Enumeration Method (OEM) are developed, and some numerical experiments have been done and compared as well.
Abstract
The axial capacity of light–gauge steel tube columns filled with concrete including recycled asphalt pavement (RAP) aggregates and recycled concrete aggregates (RCA) was investigated. A total of 51 specimens, including 6 bare steel tubes, 30 composite columns and 15 concrete-only columns were tested under uniaxial load. Fifteen concrete mixes were considered by replacing the weight of natural coarse aggregates (NA) with RCA and RAP at replacement levels of 0, 20, 40, 60, 80, and 100%. In addition, RAP and RCA were combined in the same mixes with replacement levels of (1) 20% RAP and 80% RCA; (2) 40% RAP and 60% RCA; (3) 60% RAP and 40% RCA; and (4) 80% RAP and 20% RCA. Experimental results were analyzed by reporting the ultimate capacities and the patterns of failure. Moreover, the predictions of EUROCODE 4 (EC4) and American Institute of Steel Construction (AISC) codes were checked. ABAQUS software was used to perform a finite element analysis (FEA) of the tested composite specimens. The results showed that using recycled aggregates decreased the carrying capacity of columns. Carrying capacity of light–gauge steel tubes filled with concrete including different combinations of RCA, NA and RAP aggregates can be conservatively predicted by the AISC and EC4 recommendations. Results of FEA showed a good agreement with the experimental results.
Abstract
The aim of the study is to create an effective and standard risk assessment tool that provides the company with support and security in purchasing of new products. The goal was to create a tool that complements and standardizes risk assessment forms and shows rapid results. Using the procurement risk management system, the risk associated with a given product can be determined easily and in a short time. In the process, critical areas where hazards may occur can be clearly identified and the risk can be minimized if properly managed.
Abstract
Fiber Optic Network is an advanced and modern system technology, which is used in sending pulses of laser light inside a glass of fiber over long distances, widely used in every environment with various sorts of applications in a different field. It is well-known that the main material of fiber optics is glass, therefore it is typical that the temperature can affect the glass during the thermal expansion. This effect will be applied to the properties of the optical components such as refractive index, radius curvature of the fiber optics layers, and also there is an effect on the data transfer through the fiber optics network units. In this paper, the effect of temperature degree on the optical signal and the functions of the fiber optic network will be simulated, measured, and analyzed. The result will be discussed and the conclusion will show the serious points of thermal effects on the optical signal of a fiber-optic network.
Abstract
Using alternative fuels (AF) in industry high consuming energy where fossil fuels are largely consumed may be a great solution to decrease CO2 emission and cost production. Or, when using these alternative fuels, the combustion may be difficult to control regarding the different components of AFs compared to fossil fuels. In this case, the use of the computational fluid dynamics CFD tools is a great solution to predict the AFs combustion behavior. This paper represents a computational study of petcoke and olive pomace (OP) co-combustion in a cement rotary kiln burner, established on the commercial CFD software ANSYS FLUENT. This study presents a useful key to choose an adequate simulation model that well predicts co-combustion problems. The performance of the K-ϵ turbulence models varieties (standard, Realizable, and Re-Normalization Group) combined with the hybrid finite rate/eddy dissipation model and the simple eddy dissipation model for predicting the co-combustion characteristics was investigated. The particle phase solutions are obtained using the Lagrangian approach. The performance of the mentioned model was evaluated based on the mesh accuracy, convergence time, temperature shape, and important chemical elements concentration. The predicted values of species concentrations and temperature are compared to the results obtained from the real case study and available literature. The standard K-ϵ model combined with the hybrid finite rate/eddy dissipation model gives the best results and the lower computational resources required for the 2-D model realized.
Abstract
Climate change has become a real challenge in different fields, including the building sector. Understanding and assessing the impact of climate change on building energy performance is still necessary to elaborate new climate-adaptive design measures for future buildings. The building energy consumption for heating and cooling is mainly related to the building envelope thermal performance. In this study, the winter heat loss and summer heat gain indicators are proposed to assess and analyse the potential impact of climate change on opaque building envelope elements for different climate zones in Morocco over the next 40 years. For that purpose, a one-dimensional heat transfer model is used to simulate the heat transfer through the multi-layer structure of the wall/roof. A medium climate change scenario is considered in this study. The results showed that the current average walls and roof summer heat gain is expected to increase of about 19.2–54.3% by the 2060s depending on the climate zone, versus a less important decrease in winter heat loss varies between –10.6 and –20.6%. This paper provides a reliable evaluation of the climate change impact on building envelope thermal performance, which leads to better adjustments in future building envelope designs.
Urban Transformations of Kharkiv’s Large Housing Estates
Novi Budynky and Pavlovo Pole After 1991
Harkov nagy lakótelepeinek városépítészeti átalakulása
Novi Budynky és Pavlovo Pole 1991 után
Kharkiv is the second largest city of Ukraine with a unique history of urban housing development. In the 20th century it became a field of large housing construction. More than 10 large housing estates were constructed in the period between the second half of 1950s–late 1980s following the Soviet method of prefabricated construction, which was introduced into urban planning in connection with the radical change of all architectural and construction activities in the USSR. This paper explores factors of post-socialist urban development (after the change of political regime in Ukraine in 1991) of the case study large housing areas. For the purpose of the study, two Kharkiv large housing areas were selected – Novi Budynky and Pavlovo Pole, which were designed and built in the same period (late 1950s) and were the first residential areas of Kharkiv built according to the new planning principles of Soviet prefabricated construction. Pavlovo Pole is a large housing estate located not far from the historic center regarded as a good quality housing area, intended for the Soviet “intelligentsia” while Novi Budynky is often a stigmatized area constructed mainly for the factory workers.
Key research questions are: description of the history of construction and development of Pavlovo Pole and Novi Budynky large housing estates; comparison of the specific features of their design and construction; to determine how these large housing estates are connected with the rest of the city spatially and in terms of socio-cultural aspect, in particular with the city center; to identify the reasons and content of key urban transformations in the large housing areas, such as: demolition of houses and new construction, reduction of the area of public recreational function, appropriation of deserted areas, etc.
Harkov Ukrajna második legnagyobb városa, amely egyedülálló történettel rendelkezik a városi lakásfejlesztés területén. A 20. században nagy lakásépítkezések zajlottak: az 1950-es évek második fele és az 1980-as évek vége közötti időszakban több mint 10 nagy lakótelep épült Harkovban az előregyártott építés szovjet módszerét követve, amelyet a Szovjetunióban az összes építészeti és építési tevékenység radikális változásával összefüggésben vezettek be a várostervezésbe. Ez a tanulmány az 1991-es ukrajnai rendszerváltás utáni posztszocialista városfejlesztés tényezőit vizsgálja két harkovi nagy lakótelepen. Novi Budynky és a Pavlovo Pole, a város első nagy lakótelepei, melyeket az 1950-es évek végén terveztek és építettek a szovjet előregyártott építés új tervezési elveinek megfelelően. Pavlovo Pole a történelmi központhoz közeli, ma is jó minő-ségű lakóterületnek tekinthető, amit a szovjet „értelmiségnek” szántak, míg Novi Budynky gyakran stigma-tizált városrész, amelyet elsősorban a gyári munkásoknak építettek.
A legfontosabb kutatási kérdések a következők: Pavlovo Pole és Novi Budynky nagy lakótelepei építésének és fejlődésének története; tervezésük és kivitelezésük sajátosságainak összehasonlítása; annak meghatározása, hogy ezek a nagy lakótelepek hogyan kapcsolódnak a város többi részéhez, különösen a városközponthoz térben és társadalmi-kulturális szempontból; a nagy lakóövezetekben zajló, kulcsfontosságú városi átalakulások okainak és tartalmának azonosítása, mint például: házak bontása és új építés, a nyilvános rekreációs területek csökkentése, elhagyatott területek kisajátítása stb.
Abstract
In this study, a single stage thermoelectric cooler (TER, of size: 21 × 14.2 × 13.5 cm) with thermoelectric module (TEM, of type inbc1-127. 05 with size 40 × 40 × 4.0 mm) and applied electrical power of 30 W and current of 2.5 A, was adopted to estimate the coefficient of performance (COP) of thermoelectric refrigerator (TER). The TER uses a fan to cool the heat exchange region of the TEM. The temperature of the fruit/vegetable samples used in this study was taken before and after cooling for a specific period. The temperatures at both the hot and cold sides of the TEM were also taken at every specific cooling period. The experimented TER can cool vegetable/fruit from about 27 to 5°C within 3 h. The aim of this study is to determine the COP of TER to ascertain the possible applications. The temperature gradient at the heat exchange section of TEM was used to estimate the average theoretical COP to be 0.99, the heat extracted from the cooling chamber and the power supplied was used to estimate the average practical cooling COP to be 0.52; which is within 0.4–0.7 standard COP for a single stage type of TER.
Abstract
Raw materials requirement is foremost necessary in construction sector. Due to the increase in construction activities, the raw material utilization is also increased, which may lead to depletion of the resources. The usage of M sand also increases day by day. On the other side, waste disposal is posing a major threat to environment and human health. This paper shows the investigation carried out in manufacturing fly ash bricks made by utilizing vermicompost as an alternative material for M sand, the physical and chemical properties of M sand and vermicompost are studied and they seem to be the same. In this study, an attempt is made to check the feasibility of replacement of vermicompost for M sand in brick making. The brick specimens are casted as per the mix proportions and they are tested for strength and durability at the age of 28 days. It has been identified that the vermicompost replacement at 5% and 10%, the compressive strength of the brick is 7.90 and 7.31% respectively, which is found to be nearer to the strength of the control specimen and the water absorption for all the mixes of the brick casted were below 20% as per IS code. Inclusion of vermicompost in the fly ash bricks will tend to reduce the use of M sand.
Abstract
Digital technologies had an effect on people's lives. The majority of these digital devices rely on cloud storage to meet their memory needs. Hundreds of thousands of images, videos, and audio files are being transferred to cloud storage. Thousands of people around the world access these media every second. Unauthorized access to these media must be avoided. One of the weak points for data breaches is the user-end encryption. This paper suggests a strategy for improving cloud data protection by combining the AES and blowfish encryption and decryption algorithms. AES-256 is used as the first layer, followed by blowfish as the second layer, in the hybrid solution. The output of the first layer is input to the second layer and the final result is analyzed. The proposed method also discusses other combined approaches such as AES with other traditional algorithms but the proposed method gives significant results compared to other approaches.
Abstract
Adenosine triphosphate (ATP) is an energy compound present in living organisms and is required by living cells for performing operations such as replication, molecules transportation, chemical synthesis, etc. ATP connects with living cells through specialized sites called ATP-sites. ATP-sites are present in various proteins of a living cell. The life span of a cell can be controlled by controlling ATP compounds and without the provision of energy to ATP compounds, cells cannot survive. Countless diseases treatment (such as cancer, diabetes) can be possible once protein active sites are predicted. Considering the need for an algorithm that predicts ATP-sites with higher accuracy and effectiveness, this research work predicts protein ATP sites in a very novel way. Till now Position-specific scoring matrix (PSSM) along with many physicochemical properties have been used as features with deep neural networks in order to create a model that predicts the ATP-sites. To overcome this problem of complex computation, this exertion proposes k-mer feature vectors with simple machine learning (ML) models to attain the same or even better performance with less computation required. Using 2-mer as feature vectors, this research work trained and tested five different models including KNN, Conv1D, XGBoost, SVM and Random Forest. SVM gave the best performance on k-mer features. The accuracy of the created model is 96%, MCC 90% and ROC-AUC is 99%, which are the same or even better in some aspects than the state-of-the-art results. The state-of-the-art results have an accuracy of 97%, MCC 78% and ROC-AUC is 92%. One of the benefits of the created model is that it is much simpler and more accurate.
Abstract
Scarcity of the construction materials, peculiarly the natural river sand has become a serious threat in the construction industry. Though many researchers of developed and developing countries are trying to find alternative sources for the same, the complete replacement of the fine aggregate in concrete is crucial. Geopolymer sand developed from the Industrial waste (Ground granulated blast furnace slag - GGBS) is an effective alternative for the complete replacement of the natural sand. The GGBS based geopolymer sand (G-GFA) was tested for physical and chemical properties. Upon the successful achievement of the properties in par with the natural river sand, the fresh properties (fresh concrete density & slump) and hardened properties (compressive strength, tensile strength & flexural strength) of the concrete specimens developed with G-GFA were studied. The G-GFA is obtained by both air drying (AD-G-GFA) and oven drying (OD-F-GFA) after the dry mixing of the alkaline solution and GGBS for about 10 min. Thus, developed fine aggregates were studied separately for the fresh and hardened concrete to optimize the feasible one. Superplasticizer of 0.4% is included in the concrete mix to compensate the sightly hydrophilic nature of the fine aggregates produced. The mechanical properties of the concrete with G-GFA are observed to be more than 90% close to that of the concrete developed with natural river sand. Thus, both the fresh and mechanical properties of the G-GFA concrete specimens resulted in findings similar to those of the control specimen developed with natural river sand reflecting the plausibility of G-GFA as a complete replacement choice to the fine aggregate in the concrete industry. The flaky GGBS particles merge well with the alkaline solution at room temperature itself since the former gets dried at elevated temperatures. Thus, more feasible fresh concrete properties and mechanical properties were recorded for the AD-G-GFA than the OD-G-GFA.
Abstract
Construction industry is one of the biggest sectors globally and a wide variety of materials are used to carry out various works. Particularly, cement is a material that is used in the construction of various structures and it is also the major source of emission of CO2 gas into the atmosphere which results in global warming. Many researchers have identified various replacement materials for cement as a partial substitution and carried out experiments successfully. Nano silica is widely utilized as a partial replacement for cement and a lot of research is carried out. This paper reviews the past studies in which nano silica is utilized in various building materials such as cement mortars, normal concrete and special concretes. The fresh concrete properties, strength and durability of the material are the parameters reviewed and it is apparent that by incorporating nano silica in cement it absorbs more water, which makes the mix less workable and it imparts additional strength to the concrete and also provides better durability when compared with the control specimen. Hence it has been revealed that nano silica will be a good replacement for cement as it is pozzolanic in nature and also possessing good microstructure.
Abstract
Our study aims to discover what reasons justify the physical activity of fitness consumers, and how the motivation of this physically active group can be maintained, which then may contribute to maintain a healthy society in the long run. Of the primary research procedures we chose to use the questionnaire survey method. We used cluster analysis for which we used principal components that were created with factor analysis to determine what groups can be established based on responses to the questions related to motivation and the factors that influence their choices of facilities. Based on the rank order of motivations influencing attendance of fitness sessions, fitness consumers were stratified into four different clusters. Then, segmentation of the consumers was done based on the factors influencing their choices of facilities. Our results lead to the conclusion that the motivation of consumer groups identified in our research can be sustained in the long run, the less active groups can be better involved and attracted to sports offered by fitness centres, on condition the fitness studios reliably serve these needs and provide the expected variety of services and hygienic conditions.
Abstract
Corrosion inhibition of steel by Polyurethane Extract-primer (PEP) containing plant leaf extracts was compared with Polyurethane Conventional primer (PCP) containing zinc phosphate and zinc chromate as inhibitors. The primers were investigated using gasometric technique in 5 °C steps of temperature increase from 25 to 50 °C in 1.0 M HCl as corrodent. The PEP of 34.24 percent actives compared with PCP of 56.35 percent actives gave the same inhibition efficiencies of 82.4%. Extract primers of low percent active concentration were more effective and less expensive than that of conventional primers.
Abstract
During service, notched designed components such as steam generators in the nuclear power plant usually experience fatigue damage at elevated temperatures, due to the repeated cyclic loadings during start-up and shut-down operations. Under such extreme conditions, the durability of these components is highly-affected. Besides, to assess the fatigue life of these components, a reliable determination of the local stress-strain at the notch-tips is needed. In this work, the maximum strains of circumferentially notched cylindrical specimens were calculated using the most commonly known analytical methods, namely Neuber's rule, modified Neuber's rule, Glinka's rule, and linear rule, with notch root radius of 1.25, 2.5, and 5 mm, made of modified 9Cr–1Mo steel at 550 °C, and subjected to nominal stress amplitudes of ±124.95, ±149.95, and ±174.95 MPa. The calculated local strains were compared to those obtained from Finite Element Analysis (FEA). It was found that all the analytical approximations provided unreliable local strains at the notch-tips, resulting in an overestimation or underestimation of the fatigue life. Therefore, a mathematical model that predicts the fatigue lives for 9Cr–1Mo steel at elevated temperature was proposed in terms of the applied stress amplitude and the fatigue stress concentration factor. The calculated fatigue lifetimes using the proposed model are found to be in good agreement with those obtained experimentally from the literature with relative errors, when the applied stress amplitude is ±149.95 MPa, are of 1.97%,–8.67%, and 13.54%, for notch root radii of 1.25, 2.5, and 5 mm, respectively.
Abstract
This paper presents a realization of fractional-order Band pass-filter (FOBF) based on the concepts of fractional order inductors and fractional order capacitors. The FOBF is designed and implemented using both simulation and hardware approaches. The proposed filter order is considered up to second order or less with any real positive number. One of the cases is considered when α ≤ 1 and β ≥ 1. In the second case, the filter is designed when β ≤ 1 and α ≥ 1. In order to calculate the optimal filter parameters, the modified Particle Swarm Optimization (mPSO) algorithm has been utilized for coefficient tuning. Also, a generalized approach to design any second order FOBF is discussed in this work. The realization and performance assessment have been carried out in simulation environment as well as in lab experiment with field programmable analog array (FPAA) development board. The experimental results indicate the value of efforts to realize the fractional filter.
Abstract
For the last few decades, the power sector has been restructuring throughout the world, and because of this, congestion is bound to take place in the network. Congestion can lead to market failure, violate transmission capability limits and high electricity prices, and end up threatening the power systems’ reliability and security. Increased congestion may also lead to unexpected price differences in power markets leading to market power. In a deregulated power market (DPM), the independent system operator (ISO)’s fundamental challenge is to preserve the power market’s reliability and safety by improving market efficiency when the network is congested. Therefore, congestion management (CM) is essential in DPM and is the key to the power system. This paper carries out a congestion management methods survey to bring together all recent publications in the DPM. It aims to help readers summarize progressive CM methods, along with traditional CM methods that have been discussed so far. In this paper, we have carried out a comparative survey of the various well-known CM methods.
Abstract
Flow-like landslides are a serious geologic hazard that can cause life and property loss all over the world. Mudflow is a kind of debris flow that has been classified as a non-Newtonian flow. The Smoothed particle hydrodynamics method (SPH) is a powerful tool for modeling fluids, such as debris/mudflows, which can be described in terms of local interactions of their constituent parts. In this paper, the Herschel-Buckley rheology model and SPH are used to simulate free-surface mudflow under the gate. The run-out distance and velocity of mudflow during the time are calculated with numerical simulation and compared with the laboratory result. Our results indicate the rate of increase of run-out and viscosity in the computer model is more than the experimental model and it is because of friction that is assumed to be zero. In the computer simulation, friction is exactly zero but in the experimental model, it could be measured and assumed zero. Finally, Abacus had a good result and can be used for mudflow simulation and protection of run-out distance and viscosity.
Abstract
In this study, the relationship between the structure of the supporting frame and cells is addressed.
The possible arrangements of the four primary structural elements – foundation, walls and pillars, slabs, roof – in global form as well as in a single cell are looked at. The types of connections of each support member to the support elements below are examined. In line with this, the layout and possible structure of the foundation, and the possible layout of walls and pillars as well as slab is reviewed. The main possibilities for structural design of the roof structure are outlined.
Using the concepts of cells, and arrangement and division of cells there is given some applications. The different building types that can be interpreted using arrangement of cells as well as some applications are shown.
Freund Vilmos munkássága a Fővárosi Középítési Bizottmányban
A 175 éve született építész életművének egy máig nem kutatott fejezete
The Work by Vilmos Freund in the Metropolitan Commission of Public Architecture
An Unresearched Chapter of the Work of an Architect Born 175 Years Ago
Freund Vilmos (1846 –1920), Gottfried Semper tanítványa a dualizmus korabeli Budapest egyik igen termékeny építőművésze volt. Több mint félszáz épületet alkotott a fővárosban. Főleg olasz neoreneszánsz stílusban tervezte meg épületeit. 1900 után már szinte egyáltalán nem alkotott építészként. Építészi tapasztalata megszerzését követően, 1891 körül egyre aktívabb szakmapolitikai tevékenységbe kezdett. Tanulmányunk ismerteti a Fővárosi Középítési Bizottmány szerepét, majd Freund itt végzett munkáját mutatja be, beszédeinek nagyrészt az egykorú Fővárosi Közlönyben megjelent szó szerinti rögzítése alapján. Először a gyakor lati, technológiai ügyek terén tett felszólalásait ismertetjük. Itt többek között kiviláglik Freund útburkolatokkal kapcsolatos komoly tudása, és az, hogy figyelemmel kísérte azon útvonalak állapotát, ahol általa tervezett paloták álltak. Ezt követik a más építészek plánumaival és épületeivel kapcsolatos megszólalásai. A vele egykorú vagy nála fiatalabb alkotók műveivel kapcsolatos javaslatait, illetve véleményét ismerhetjük meg. Végül pedig a „legizgalmasabb” témát, a városrendezés terén elhangzott hozzászólásait tárgyaljuk. Meglepő, hogy néhány, városképileg igen meghatározó épület létrejöttében vagy megépült formájuknak kialakításában is szerepe volt. Például az új tőzsdepalota kezdeményezését és Szabadság térre helyezését két másik építész (Hauszmann Alajos és Quittner Zsigmond) mellett ő kezdeményezte. A piaristák Duna-korzón álló épületének megjelenésére is hatással volt. Freund az igen jelentős építészeti életművén kívül a szakmapolitikai tevékenységével is figyelemre méltót alkotott Budapesten.
Vilmos Freund (1846–1920) was a prominent Hungarian architect who lived during the period of the Austro-Hungarian Empire. He was a student of Gottfried Semper. The majority of the buildings by Freund were built in Budapest. His most preferred style was the Italian Neo-Renaissance. From about 1891 he had an architectural political carrier too. After 1900 he radically reduced the number of his designing work. This study is written about his work in the Metropolitan Commission of Public Architecture (Fővárosi Középítési Bizottmány). His speeches in this commission survived until today as word-by-word recordings published in the old bulletins. The first chapter deals with his speeches in relation to practical, technological affairs for example the paving of the roads of Budapest. He reported his opinion of the designs by other architects, this is the topic of the second chapter. Finally, we can read about his speeches about the great city planning actions. It is interesting that several buildings of Budapest were constructed because he and a few of his colleges initiated them.
Abstract
Quantum dots (QDs) or semiconductor nanocrystals are luminous materials with unique optical properties that can be fine-tuned by varying the size of the material. Chalcogenide QDs show strong quantum confinements effects owing to the fact that the exciton Bohr radius is much larger than the particle size, and tunable energy bandgap leads to widespread technological interest in near-infrared optical devices. In this communication, one dimensional Cu2SnS3 and PbSexS1-x QDs is modeled by a particle in a box model which was used to compute energies and density of states. The density of states and the energy level of QDs are determined as a function of the strengths of the potential walls of the inner box. The results exhibit that the density of states decreases exponentially with an increase in the energy level of QDs. The density of states at lower energy levels is more significant than what is observed in higher energy levels.
Abstract
Natural and man-made disasters are vital issues that led to the increasing number of migrants, many of them stayed displaced for decades this requires more permanent dwellings. The main aim of the study is to investigate the impact of the bottom-up construction method on developing migrant’s shelters energy and thermal comfort performance. Dynamic simulation tool Indoor Climate and Energy (IDA ICE 4.8) has been used to assess nine different scenarios. The results quantified that the annually delivered energy and thermal comfort accepted hours of proposed scenario nine (S9) is better compared to base-case scenario one (S1) by 63% kWh and 4,215 h respectively. Methodologies and results of this paper can be adopted and applied for various places of the world affected by migration issue.
Abstract
Impacts of autonomous truck’s passes on pavement have been analyzed in this research. Two types of lateral positioning namely zero wander and uniform wander along with a super single wide tire and a dual tire have been analyzed with variable traffic speeds in ABQUS. The study concludes with the results in favor of usage of a super single wide tire under a uniform wander mode. The highest amount of pavement damage in terms of maximum rut depth is caused by the dual wheel assembly moving under a zero-wander mode. The magnitude of rut depth increases by a factor of two when a dual tire assembly is used instead of a wide tire assembly. At a uniform wander mode, rut depth increases by 0.2 mm for every 10 km/h decrease in traffic speed within 90 km/h to 70 km/h range.
Abstract
The target (dependent) variable is often influenced not only by ratio scale variables, but also by qualitative (nominal scale) variables in classification analysis. Majority of machine learning techniques accept only numerical inputs. Hence, it is necessary to encode these categorical variables into numerical values using encoding techniques. If the variable does not have relation or order between its values, assigning numbers will mislead the machine learning techniques. This paper presents a modified k-nearest-neighbors algorithm that calculates the distances values of categorical (nominal) variables without encoding them. A student’s academic performance dataset is used for testing the enhanced algorithm. It shows that the proposed algorithm outperforms standard one that needs nominal variables encoding to calculate the distance between the nominal variables. The results show the proposed algorithm preforms 14% better than standard one in accuracy, and it is not sensitive to outliers.
Abstract
In this research, ceramic bricks were produced based on natural zeolite from Tokaj (Hungary) using the dry pressing technique. The microstructure, morphology and properties of the produced samples were examined via scanning electron microscopy, X-ray diffraction and X-ray fluorescence. The X-ray investigation revealed various minerals in the natural zeolite; moreover, the samples’ physical and thermal properties were also investigated. The sintering temperature and composition play a major role in the microstructure and the properties of the prepared ceramic samples. The produced ceramics bricks have excellent thermal insulation and good mechanical strength. The results of this research work confirm the potential use of natural zeolite from Tokaj as an eco-friendly building material.
Abstract
According to the energy development strategy of Ukraine, implementation of energy efficient buildings is needed, in which external protections are converters of solar energy into heat. The article presents studies of solar coating with direct coolant supply. Studies of the average value of the heat loss coefficient of the solar coating were also carried out. As a result, the efficiency of the solar coating under the mode of forced circulation of the coolant is 0.67, at natural circulation of the coolant – 0.57 and at its direct supply is 0.71. Experimental researches of thermal and physical parameters of a solar covering and system of heat supply on its basis showed in the corresponding dependences influence on its thermal characteristics of dynamic modes of the heat carrier, energy, kinetic characteristics of the environment.
Abstract
Horizontal good technology is one of the recent methods in the drilling and exploitation of geological formations in the best and optimal ways, because of the many and comprehensive advantages that these wells enjoy with the most important measurement and prediction index called productivity index. Which is equivalent to several times higher than the vertical well productivity index, if the field is invested by drilling vertical wells only.
The current research focuses on calculating the productivity index by proposing the development point of view of the reservoir formation in the Burgan oil field through the production of oil from the production units approved in the formation (MB21, MC1, MC2) by using of horizontal good technology and comparing it with the value of the productivity index of vertical wells in the same production units.
Well-known published methods adopted in the case of steady state and pseudo steady state were used in the calculations of the productivity index, and by comparison with the standard observed results, it was found that the Joshi method was closer than others in the calculations of the productivity index for both steady and pseudo steady state cases. Then the calculations were completed taking into account all conditions and factors that have a significant role in the value of the calculated productivity index.
The obtained results revealed that PI increases with [well length, isotropy ratio (Kv/Kh), well thickness vs. well length] increase, while it was decreased with [ drainage area] increase in the case of steady state conditions. Also, the PI increase with length increase in the case of Pseudo steady state condition for all the studied methods, and both of Kuchuck and Economides methods seem to be close in obtained results, but Economides is the closest one to the reality and importance in application with the present case. Completion configuration has an effluence on the PI, and it is increasing with the increase of well opening to the production for such well length.
Also, all the results indicated that the use of this type of technology in the field development is good and promising, and gave valuable, excellent, and optimistic results for the future production of the field in a profitable manner.
Abstract
For the past few decades innovation in construction material has grown a lot. This leads to special concrete such as self-compacting concrete, geopolymer concrete, self-healing concrete, etc. To prepare a special concrete apart from regular concreting material some sort of special materials was also needed, like mineral and chemical admixtures. Hence it is necessary to study the effect of these admixtures in cement paste and mortar before studying the same in concrete. Hence an attempt is made to study the effect of mineral and chemical admixtures in the fresh and hardened properties of cement paste and mortar. For this study ultrafine natural steatite powder is taken as mineral admixture and polycarboxylic based superplasticizer and glenium stream 2 were taken as chemical admixtures. Ultrafine natural steatite powder was used as additive to cement in various percentages like 0%, 5%, 10%, 15%, 20% and 25%. Superplasticizer and viscosity modifying admixture were taken as 1.5% and 0.5%, respectively. Then various combinations were worked out. To study the fresh property of cement paste consistency, initial setting time and miniature slump cone test were done based on the results yield stress of cement paste also calculated empirically. To study the hardened property compression test on cement mortar was done. Based on the test results it is clear that the addition of ultrafine natural steatite powder increases the water demand hence reduces the workability. On the other hand, it increases the compressive strength up to a certain limit. Adding superplasticizer increases the workability and reduces the water demand and viscosity modifying admixture reduces the bleeding and segregation effects hence increases the compressive strength.
Abstract
Educational data mining is an emerging exquisite field that has been successfully implemented in higher education. One of the best ways to increase the efficiency of this emerging phenomenon is to select efficient professors and effective teaching methods. This study is intended to show academic success factors to have better management in student curriculum, contextualizing the progress and to prevent unfavorable conditions for students. In this research, students of Shahrood University of Technology were studied. Initially, 3,765 samples of students' educational background were considered. Then, pre-processing was performed to make the data normalized. Next, several predictive models were developed using a supervised data mining approach. Next, five algorithms by the best result were selected. Comparing the results of algorithms applied to data, the two algorithms, radial basis function network and the Naïve Bayes with respectively value F-measure 0.929 and 0.942 showed more accurate results. Finally, the most effective feature was selected, the attributes ‘maximum semester’ and ‘the total number of units dropped’ were ranked an the most important, and the three attributes of ‘the basic courses average’, ‘the number of units of main courses’ and ‘the total average’, were placed in the next ranks.
Abstract
In recent years, managers of both private and public organizations in developing countries have been struggling to double production and improve service delivery in their organizations. Successful organizations in the western world were, however, identified with the use of Information Technology (IT). The paper examined the magnitude of IT and its application in human resource management. Four organizations from private and public sectors were selected from all. Two organizations from each sector, members of staff, Human Resource (HR) professionals and managers of these organizations were targeted. A structured questionnaire was used to collect data from the staff and unstructured interviews were designed to gather data from the HR practitioners and managers of these organizations. A statistical package for social sciences (SPSS) was used to analyse the data. In general, about 76.9% of the participants said that IT application in HR functions enhances organizational productivity. The selected organizations could boast of basic IT facilities, but their numerical strength still remains a challenge especially among organizations in the public sector. Organizations in both sectors must invest more in IT and its related accessories as a means of solving problem of inadequacy. Internet connectivity and company website were lacking in some organizations across both sectors and should be considered so as to improve upon the human resource functions and quality service delivery in the deprived regions of Ghana. Staff motivation, wage and salaries, strategic management and organizational leadership were mentioned as factors when put together with IT would augment productivity in any given economy.
