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Authors: Barhm Mohamad, Jalics Karoly, Andrei Zelentsov and Salah Amroune

Abstract

In this work a multilevel Computational Fluid Dynamics (CFD) analysis has been applied for the design of a Formula race car exhaust muffler with improved characteristics of sound pressure level (SPL) and fluid dynamic response. The approaches developed and applied for the optimization process range from the 1D to fully 3D CFD simulation, exploring hybrid approaches based on the integration of a 1D model with 3D tools. Modern mufflers typically have a complex system of chambers and flow paths. There are a variety of sound damping and absorbing mechanisms working to quiet the sound flowing through a muffler and piping system. Two calculation methods were selected for this study. The muffler has a complex inner structure containing perforated pipe and fiber material. Computer-aided design (CAD) file of the muffler was established for developing Finite Element Analysis (FEA) model in AVL BOOST v2017 and another commercial advanced design software (SolidWorks 2017). FEA model was made to monitor the flow properties, pressure and velocity. After the model was verified, sensitivity studies of design parameters were performed to optimize the SPL of the muffler. The software analysis results are included in the paper. Recommendations are made for obtaining smoother SPL curves for various measurement methods.

Open access
Authors: Mariam Achbal, Abdellatif Khamlichi and Fadoua El Khannoussi

Abstract

In this work, a numerical method is proposed in order to achieve design optimisation of phased array (PA) probes for the special application of defects detection in thin films. This approach relies on an extended Fourier-based model that was adapted to predict the two-dimensional ultrasonic displacement field taking place in a thin plate under individual excitation of PA probe elements which have arbitrary orientation with respect to the examined part surface. Excitation is applied through a fluid couplant and is operated at scheduled delays that are managed to enable emission of constructive pulses. This gives the possibility to steer sound waves towards a direction and to focalize the beam in a selected point. An optimisation algorithm based on the concept of pattern search that does not require evaluation of a gradient was used to find the best match in the multidimensional analysis space of possibilities including the elements orientation angles, the elements lengths, the inter-elements distances and work frequency. Optimisation was performed with the objective to maximize the displacement amplitude at the focal point while minimizing simultaneously the effect of beam side lobes. The results obtained by this approach reveal that focalisation can be achieved with enhanced features in comparison with previous algorithms assuming linear elements that are parallel to the surface of the plate.

Open access
Authors: Norbert Novák, Péter Miklós Kőmíves, Mónika Harangi-Rákos and Károly Pető

Abstract

The role of rural areas partly changed in the last decades. The countryside is still functioning as the main food producer of the world and this role became much more important because of the global population growth and because of the change in dietary habits. But other rural functions appeared just like recreation, health preservation, and on the other hand the different ecological functions' importance increased. The population living in the countryside is continuously decreasing as more and more people try to move into urban areas. One of the main aims of this article is to give a brief literature overview on the services needed in the rural areas in order to stop migration from the countryside to the cities. Based on extensive literature review the article summarizes the changing functions of the countryside and tries to list those developments which are needed to preserve rural population.

Open access

Abstract

In the building mechatronics research centre of University of Debrecen, Faculty of Engineering, a new laboratory has been designed, named “Cyber-physical and intelligent robot systems laboratory”. The possibility to design and test unique and platform-independent systems was among the main goals, hoping that the system itself and its advancements may later be used in manufacturing industries as well.

Fulfilling the needs of “Industry 4.0” is a challenging task, as it requires every single device (e.g. industrial robots) to be connected to the same network, where they may be monitored and controlled. However, there are some factors that limit this, such as the periodical “instability” that some machines have, caused by singularity points.

The following material studies these so-called singularities of a KUKA KR5 industrial welder robot placed in a robot cell, from an engineering viewpoint.

Open access
Authors: Matthias Brand, Hans-JÜrgen Rumpf, Zsolt Demetrovics, Astrid MÜller, Rudolf Stark, Daniel L. King, Anna E. Goudriaan, Karl Mann, Patrick Trotzke, Naomi A. Fineberg, Samuel R. Chamberlain, Shane W. Kraus, Elisa Wegmann, JoËl Billieux and Marc N. Potenza

Abstract

Background

Gambling and gaming disorders have been included as “disorders due to addictive behaviors” in the International Classification of Diseases (ICD-11). Other problematic behaviors may be considered as “other specified disorders due to addictive behaviors (6C5Y).”

Methods

Narrative review, experts' opinions.

Results

We suggest the following meta-level criteria for considering potential addictive behaviors as fulfilling the category of “other specified disorders due to addictive behaviors”:

1. Clinical relevance: Empirical evidence from multiple scientific studies demonstrates that the specific potential addictive behavior is clinically relevant and individuals experience negative consequences and functional impairments in daily life due to the problematic and potentially addictive behavior.

2. Theoretical embedding: Current theories and theoretical models belonging to the field of research on addictive behaviors describe and explain most appropriately the candidate phenomenon of a potential addictive behavior.

3. Empirical evidence: Data based on self-reports, clinical interviews, surveys, behavioral experiments, and, if available, biological investigations (neural, physiological, genetic) suggest that psychological (and neurobiological) mechanisms involved in other addictive behaviors are also valid for the candidate phenomenon. Varying degrees of support for problematic forms of pornography use, buying and shopping, and use of social networks are available. These conditions may fit the category of “other specified disorders due to addictive behaviors”.

Conclusion

It is important not to over-pathologize everyday-life behavior while concurrently not trivializing conditions that are of clinical importance and that deserve public health considerations. The proposed meta-level-criteria may help guide both research efforts and clinical practice.

Open access
Authors: Eszter Kotyuk, Anna Magi, Andrea Eisinger, Orsolya Király, Andrea Vereczkei, Csaba Barta, Mark D. Griffiths, Anna Székely, Gyöngyi Kökönyei, Judit Farkas, Bernadette Kun, Rajendra D. Badgaiyan, Róbert Urbán, Kenneth Blum and Zsolt Demetrovics

Abstract

Background and aims

Changes in the nomenclature of addictions suggest a significant shift in the conceptualization of addictions, where non-substance related behaviors can also be classified as addictions. A large amount of data provides empirical evidence that there are overlaps of different types of addictive behaviors in etiology, phenomenology, and in the underlying psychological and biological mechanisms. Our aim was to investigate the co-occurrences of a wide range of substance use and behavioral addictions.

Methods

The present epidemiological analysis was carried out as part of the Psychological and Genetic Factors of the Addictive Behaviors (PGA) Study, where data were collected from 3,003 adolescents and young adults (42.6% males; mean age 21 years). Addictions to psychoactive substances and behaviors were rigorously assessed.

Results

Data is provided on lifetime occurrences of the assessed substance uses, their co-occurrences, the prevalence estimates of specific behavioral addictions, and co-occurrences of different substance use and potentially addictive behaviors. Associations were found between (i) smoking and problematic Internet use, exercising, eating disorders, and gambling (ii) alcohol consumption and problematic Internet use, problematic online gaming, gambling, and eating disorders, and (iii) cannabis use and problematic online gaming and gambling.

Conclusions

The results suggest a large overlap between the occurrence of these addictions and behaviors and underlies the importance of investigating the possible common psychological, genetic and neural pathways. These data further support concepts such as the Reward Deficiency Syndrome and the component model of addictions that propose a common phenomenological and etiological background of different addictive and related behaviors.

Open access
Authors: Eszter Kotyuk, Anna Magi, Andrea Eisinger, Orsolya Király, Andrea Vereczkei, Csaba Barta, Mark D. Griffiths, Anna Székely, Gyöngyi Kökönyei, Judit Farkas, Bernadette Kun, Rajendra D. Badgaiyan, Róbert Urbán, Kenneth Blum and Zsolt Demetrovics

Abstract

Background and aims

Changes in the nomenclature of addictions suggest a significant shift in the conceptualization of addictions, where non-substance related behaviors can also be classified as addictions. A large amount of data provides empirical evidence that there are overlaps of different types of addictive behaviors in etiology, phenomenology, and in the underlying psychological and biological mechanisms. Our aim was to investigate the co-occurrences of a wide range of substance use and behavioral addictions.

Methods

The present epidemiological analysis was carried out as part of the Psychological and Genetic Factors of the Addictive Behaviors (PGA) Study, where data were collected from 3,003 adolescents and young adults (42.6% males; mean age 21 years). Addictions to psychoactive substances and behaviors were rigorously assessed.

Results

Data is provided on lifetime occurrences of the assessed substance uses, their co-occurrences, the prevalence estimates of specific behavioral addictions, and co-occurrences of different substance use and potentially addictive behaviors. Associations were found between (i) smoking and problematic Internet use, exercising, eating disorders, and gambling (ii) alcohol consumption and problematic Internet use, problematic online gaming, gambling, and eating disorders, and (iii) cannabis use and problematic online gaming and gambling.

Conclusions

The results suggest a large overlap between the occurrence of these addictions and behaviors and underlies the importance of investigating the possible common psychological, genetic and neural pathways. These data further support concepts such as the Reward Deficiency Syndrome and the component model of addictions that propose a common phenomenological and etiological background of different addictive and related behaviors.

Open access

Abstract

Background and aims

The literature has proposed two types of problematic smartphone/internet use: generalized problematic use and specific problematic use. However, longitudinal findings on the associations between the two types of problematic use and psychological distress are lacking among East-Asians. The present study examined temporal associations between both generalized and specific problematic use of the smartphone/internet, and psychological distress.

Methods

Hong Kong University students (N = 308; 100 males; mean age = 23.75 years; SD ± 5.15) were recruited with follow-ups at three, six, and nine months after baseline assessment. All participants completed the Smartphone Application-Based Addiction Scale (for generalized problematic smartphone/internet use), the Bergen Social Media Addiction Scale (for specific problematic smartphone/internet use), and the Hospital Anxiety and Depression Scale (for psychological distress) in each assessment. Latent growth modeling (LGM) was constructed to understand temporal associations between generalized/specific problematic use and psychological distress.

Results

The LGM suggested that the intercept of generalized problematic use was significantly associated with the intercept of psychological distress (standardized coefficient [β] = 0.32; P < 0.01). The growth of generalized problematic use was significantly associated with the growth of psychological distress (β = 0.51; P < 0.01). Moreover, the intercept of specific problematic use was significantly associated with the intercept of psychological distress (β = 0.28; P < 0.01) and the growth of psychological distress (β = 0.37; P < 0.01).

Conclusion

The initial level of problematic use of smartphone/internet increased the psychological distress among university students. Helping young adults address problematic use of the smartphone/internet may prevent psychological distress.

Open access

Abstract

Background and aims

The literature has proposed two types of problematic smartphone/internet use: generalized problematic use and specific problematic use. However, longitudinal findings on the associations between the two types of problematic use and psychological distress are lacking among East-Asians. The present study examined temporal associations between both generalized and specific problematic use of the smartphone/internet, and psychological distress.

Methods

Hong Kong University students (N = 308; 100 males; mean age = 23.75 years; SD ± 5.15) were recruited with follow-ups at three, six, and nine months after baseline assessment. All participants completed the Smartphone Application-Based Addiction Scale (for generalized problematic smartphone/internet use), the Bergen Social Media Addiction Scale (for specific problematic smartphone/internet use), and the Hospital Anxiety and Depression Scale (for psychological distress) in each assessment. Latent growth modeling (LGM) was constructed to understand temporal associations between generalized/specific problematic use and psychological distress.

Results

The LGM suggested that the intercept of generalized problematic use was significantly associated with the intercept of psychological distress (standardized coefficient [β] = 0.32; P < 0.01). The growth of generalized problematic use was significantly associated with the growth of psychological distress (β = 0.51; P < 0.01). Moreover, the intercept of specific problematic use was significantly associated with the intercept of psychological distress (β = 0.28; P < 0.01) and the growth of psychological distress (β = 0.37; P < 0.01).

Conclusion

The initial level of problematic use of smartphone/internet increased the psychological distress among university students. Helping young adults address problematic use of the smartphone/internet may prevent psychological distress.

Open access
Authors: DONATELLA FIORANI, MARTA ACIERNO, SILVIA CUTARELLI and ADALGISA DONATELLI

The use of digital technologies to study architecture and landscape has begun to represent an innovative aspect of the research when it started to allow the dynamic association (as input and output) of images and alphanumeric data: the different combination of this information through inferences and algorithms and the consequent generation of new data has freed digitisation from a strictly instrumental role making it a new methodological approach in itself.

As a matter of fact, recently architectural research has begun to take an interest in the problem ‘from within’, working not only on the application of computer tools but, more consciously, on their configuration. The work carried out by the Sapienza research group is aimed at developing ontologies and inferential models specifically dedicated to the representation of historical buildings and is devoted to the implementation of a national GIS platform for the historical centres, the Risk Map of the Italian Ministry of Cultural Heritage and Activities and Tourism.

This kind of work involves a series of methodological issues specially oriented to the definition of the role of the history of architecture in itself and its use for the conservation project. These arguments are developed within this essay, mainly focused on: type and quality of information deriving by the new procedures; interpretative components that fuel the new research methods; cost/benefit ratio in the use of ‘analogue’ and ‘digital’ approaches; future prospects of the two different (traditional and digital) investigative strategies. Moreover, both of the fields of digital research developed by the group (ontology and Risk Map) are here summarised.

Restricted access