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Abstract

With the development of society and economy, people pay more and more attention to thematic landscape architectural design featuring various cultures. Landscape architectural design is no longer only satisfied with the standardized, identical design style, but should focus on some specific cultural communication functions. In the thematic landscape architectural design, the use of cultural symbols can reflect the characteristics of the park. Through some research and practical design, the design method of using cultural symbols in landscape architectural design is summarized: from finding cultural elements to design language transformation.

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Abstract

This study presents the frequency control of hybrid deregulated power system. The power system is supplied with appropriate system non-linearity's for practicality. A resilient model predictive control based two degree of freedom proportional integral derivative controller is designed. The Covid-19 based optimization algorithm is applied for optimization purpose. The impact of solar and wind on system dynamics are also examined. Further, the capacitive energy storage is also incorporated to check its influence. The distribution companies' participation matrix changes with market fluctuations, so the matrix is varied to check its impact. Lastly, sensitivity assessment is performed to analyze the strength of proposed controller optimized gains achieved under nominal conditions.

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Abstract

The application of natural ventilation strategies in high-rise office buildings is considered one of the most promising trends to address high energy performance and enhance the indoor thermal comfort levels in interior office spaces. In this regard, this study attempts to assess the potential of natural ventilation strategies of a specific, previously investigated, envelope design of a high-rise office building located in a temperate climate zone. Different summer natural ventilation approaches were tested using the building energy simulation program IDA ICE 4.8, evaluating thermal comfort and energy demand. The findings indicated that considerable energy savings can be achieved, compared to conventional mechanical ventilation and air conditioning systems.

Open access

Abstract

Previous studies introduced the shiftability condition for successful gearshift, based on the dog clutch kinematics model containing several parameters. This study analyzes the effect of these parameters on the dog clutch shiftability. A method to study the impact of parameters is proposed. The influence of chosen parameter domains is shown. Their influence is recognized based on the shiftability map and the engagement probability. The initial relative position showed a periodic effect within one pitch region. The teeth number, axial speed, and the backlash positively affected the engagement probability, while the mismatch speed and the overlap distance showed a negative effect. The analysis showed lower limit values for the axial speed and the backlash but higher limit values for the mismatch speed and the overlap distance.

Open access

Abstract

The current research aimed to obtain mean pressure distribution over an air-inflated membrane structure using Computational Wind Engineering tools. The steady-state analysis applied the Reynolds-Averaged Navier-Stokes equations with the k ε standard turbulence model. The pressure coefficients were compared with former experimental results to validate the numerical solution. Significant errors were detected close to the critical flow separation points when comparing the numerical results with the wind tunnel tests. However, these errors are local, and the numerical methodology provides accurate results in those areas with minor turbulence motion influence. In general, the numerical solution provided good approximation of the pressure coefficient fields.

Open access

Abstract

Due to the increase in earthquake activity in Iraq and Middle East during the last two decades, the study and understanding of probable destructive action and the best method to mitigate this effect became more important. So, many improvements and mitigation methods can be used. In this study, the use of permeation grout technique was adopted to prevent the existing soil condition in urban area by using cement kiln dust and bentonite clay. The tests were executed by using 1 g shaking table apparatus to simulate a sinusoidal motion (vibration) at specified different frequencies. The liquefaction phenomena were observed for loose saturated sand at 60 s, 25 s, and 10 s for 0.5 Hz, 0.75 Hz, and 1 Hz, respectively. After mitigation process, the soil liquefaction did not occur until 100 s, 60 s, and 30 s, for the same mentioned frequencies. Besides, the use of cement kiln dust decreases the liquefaction potential and increase the factor of safety.

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Pollack Periodica
Authors:
Rasha Ali Kamil
,
Huda M. Atiea
,
Ali Abbas Kadhem
,
Layth Abdulrasool Alasadi
, and
Qusay A. Jabal

Abstract

In this article, polymer-modified concrete was studied to present the effect of using additives on its mechanical properties. This will be achieved by employing a high-performance super plasticizing admixture that significantly enhances polymer-modified concrete mechanical capabilities. The study indicates that the polymer styrene-butadiene rubber (used increases concrete mechanical properties by 10% by weight. When the dosage exceeds 10% by weight of cement, the compressive, tensile, and flexural strengths of polymer-modified concrete are diminished. With the addition of a superplasticizer with a ratio of 1.2%, regular polymer-modified concrete compressive strength has increased from 34.3 to 42.9 MPa for a 10% polymer/cement ratio. Additionally, this superplasticizer enhanced the Material's flexural and tensile strength.

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Abstract

Multimodal biometric systems have been widely implemented in a variety of real-world scenarios due to their ability to overcome limitations associated with unimodal biometric systems. This paper is focused on the combination of the face, ear and gait in a unified multimodal biometric identification system using handcrafted features. These approaches provide robust and discriminative features to solve the biometric problem. In this research, speed up robust features and histogram of oriented gradients approaches have been used to extract features from face, ear and gait. The extracted features are optimized using genetic algorithm and classified using Levenberg-Marquardt backpropagation neural network. The system performance is evaluated on constrained and unconstrained dataset conditions.

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Abstract

This research paper exhibits the design of a V-shaped cantilever beam as a micro Energy Harvester (EH) having Piezoelectric (PZT) as its energy source for biomedical applications. PZT source based materials have the ability to convert the mechanical energy into electrical energy. Low-power biomedical devices mostly operate using electrical energy (i.e. batteries). But batteries are treated as a bio-hazard due to the massive use of biomedical applications. To overcome this toxic bio-hazard, the proposed PZT based V-shaped cantilever beam of micro EH can solve the limitations. To perform the experimental work, the cantilever beam design parameters - length, width and thickness have been considered and simulated using COMSOL Multiphysics to get the resonant frequency of 156.19 Hz which is lower than previous research work. It was observed that the obtained lower resonant frequency can be converted into AC voltage (mV) using PZT material. To convert the output AC voltage (mV) into DC voltage, a circuit of an Ultra-Low-Power (ULP) EH will be designed in LTSPICE software. Finally, the integration of the both V-shape cantilever beam and the ULP EH circuit will be implemented in PCB hardware to generate the output power (10 µW), will be stored in super-capacitor for biomedical devices-pacemaker.

Open access

Abstract

Side friction refers to combined variables indicating the degree of interaction between the activities and the traffic stream. The condition worsens when the transport demand and road-side activities increase, leading to inefficient traffic performance. This study has been focused on evaluating side friction impacts in terms of capacity and speed. Four links divided and undivided streets in Al-Najaf City, Iraq, were selected and on-street parking, pedestrian activities, entry-exit maneuvers, and temporary parking vehicles are considered as side friction elements. The results show about a 47% reduction in speed and about a 49% reduction in the capacity at a very high side friction level. Finally, a speed-predicting model has been developed for predicting the speed under side friction impacts.

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