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Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development of new energy management systems for sintering processes with high energy consumption and generally carried out with traditional recipes has become an important research topic nowadays. It has been focused on homogeneous temperature distribution in the furnace used in the sintering process. If the temperature difference is high in the furnace, the internal structure of the materials can show serious changes. In this study, transient numerical design and analysis were carried out from room temperature to 1100 °C. The temperature changes of the samples placed at different locations in the furnace with the dimensions of 1070x1580x1030 mm were numerically investigated as transiently. In numerical studies, room temperature and initial furnace temperature were defined as the initial conditions. The boundary conditions are given as heat flux on the heater surfaces and convection outside the furnace. At the end of numerical solutions, temperature values were found inside the furnace and on the samples transiently. It was showed that the temperature differences between the samples were high that is expected at the beginning, but these differences decreased to about 17 °C in the steady conditions. Unlike the studies in the literature, the condition of the samples in a protected chamber, not under the influence of direct radiation, was examined and it was observed that the temperature differences decreased by up to 2 °C. In the analysis, time-dependent temperature distributions and temperature differences are given comparatively for two different cases. [ABSTRACT FROM AUTHOR]

The effect of helicopter rotor blade tip shape on overall aircraft noise level is analyzed, in forward flight conditions. The infamous HART-II experimental data is used as a base for validations. Commercially available CFD software Ansys/Fluent is used to model the flow field over rotor-body interaction with moving-deforming meshes. The blades are modelled individually to match the actual physical blade geometry and blade movement. The acoustics calculations are performed via FW-H modelling of the software. HART-II blade has a rectangular blade tip planform. Four different tip shapes are modeled and analyzed in addition to the original blade planform. Baseline case of HART-II experiment is used for the predictive calculations. The predictions show that the least sound pressure level obtained by %10 c notched tip shape having 10-degree anhedral angle with 2,23 dB(A) difference amongst other four tip shapes. [ABSTRACT FROM AUTHOR]

The main purpose of this article is to present and analyze some opinions of Yūsuf alQaraḍāwī (1926-2022), one of the most influential jurists in the field of fiqh from the 1970s to the present, by highlighting the changes in the historical context. In his life span of more than ninety years, al-Qaraḍāwī played an active role in the establishment of Islamic institutions in addition to his contributions to almost every field of Islamic sciences. He has declared at every opportunity that Islamic Law has the potential to produce solutions for any era and place and emphasized that the only way to do this is to activate the mechanism of ijtihad. In his books al-Ḥalāl wa’l-Ḥarām fi’l-Islām and Fatāwā mu‘āṣira, among the principles he based his fatwās, he noted that he did not imitate a particular madhhab and that he went beyond all four madhhabs and made full use of the heritage of fiqh. He specifically declared that he did not adopt a dissenting view on any issue about which there was a definite ijmā‘ (al-ijmā‘ al-mutayaqqin). One of alQaraḍāwī's contributions to the field of fiqh is Islamic Criminal Law. In addition to expressing his views on this field in his books in which he recorded his fatwās and in some of his other works, he also analyzed the punishment of apostasy specifically in his work titled Jarīmat al-ridda, but he wrote fi’l-fiqh al-jinā'ī wa'l-‘ikābī fi'l-Islām a few years before his death to collect his views on the subject in a single work. Although al-Qaraḍāwī prefers one of the views of the four madhhabs in this work, he goes beyond this framework in some issues and presents different views on the provisions about which ijmā‘ is claimed to have been realized. The first of his opinions in this section is about the punishment of rajm-stone to death. Although al-Qaraḍāwī's opinion on this issue before 1972 cannot be determined, it is understood from his statements at that time that he adopted the view that rajm punishment is a ta‘zīr punishment (under the discretion of judge or ruler), but shortly before his death, he abandoned this view and opted that rajm is not an Islamic punishment. His interpretation of the concept of “muḥṣan”, which is considered as a criterion for the change of punishment in the act of adultery, as “the fact that the party(ies) were married at the time they committed this act” is one of the views that he diverged from the tradition. Among his prominent opinions are: The punishment for drunkenness is ta‘zīr, the lawmaker can determine an appropriate punishment for this crime according to the time and place, the use of drugs, regardless of their kind or names, is forbidden, and those who use them will be punished with a deterrent sanction, and those who trade and propagandize can be sentenced to death by way of ta‘zīr, in the crime of theft, niṣāb (quorum) of the stolen property determined in the hadiths is not compulsory and can be determined by a committee of experts in line with changing conditions, the different punishments for apostasy according to the position of the apostate is another controversial view in this area. al-Qaraḍāwī’s views have created a serious reflection in the academic world and paved the way for many critical studies. In our study, first, the principles that al-Qaraḍāwī declared to be the basis of his fatwās are presented. Then, his views in the field of criminal law were presented and analyzed. Since the two prominent jurists of the period, Abū Zahrā and Muṣṭafā Zarqā, had a significant influence on the formation of his views, their views on the subject are also included in the study. Finally, some evaluations are made in the light of the methods of the early jurists by focusing on the problems identified in the method al-Qaraḍāwī followed in constructing his views analyzed in this study. al-Qaraḍāwī’s corpus published in 2022, which brought together 105 of his works, was consulted to determine his views. In addition to Abū Zahrā’s al-Jarīma and al-‘Uqūba on Islamic Criminal Law, his book of fatwās and Zarqā's Fatāwā were among the works that were consulted extensively in this study. [ABSTRACT FROM AUTHOR]

Copyright of Selcuk Law Review / Selçuk Üniversitesi Hukuk Fakültesi Dergisi is the property of Selcuk Law Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aims to investigate computationally the effect of the backward-facing step on the heat transfer from flush-mounted three electronic chips located downstream of the backward step. Heat transfer is compared for two different step heights and two distances of chips from backward facing step. Heat transfer is also compared with the case without backward facing steps. For this purpose, conservation, and Std. k-ω model equations considering two-dimensional, incompressible flow are solved by Computational Fluid Dynamics (CFD) method using ANSYS-Fluent software. Velocity, temperature and pressure distributions are obtained and compared for five different cases. Presence of backward-ward facing step decreases the heat transfer according to base case without backward-facing step, and high step height and short distance of chips from backward-facing step also increases this negative effect. When all chips' average Nusselt numbers are examined, the average Nusselt number decreases by 12,32%, 14,76%, 22,28%, and 22,69%, respectively in the 2nd, 3rd, 4th, and 5th geometries. So possible backward-facing step effect of other circuit elements during placement of electronic chips on circuit boards must be accounted in the thermal design of printed circuit boards. [ABSTRACT FROM AUTHOR]

In the present work, a numerical methodology is developed for affordable and accurate analysis of helicopter rotor noise in forward flight. The flow field is obtained using unsteady compressible flow analyses using commercially available computational fluid dynamics (CFD) solver FLUENT. Azimuthal variations of the flap and pitch motions of the blades are prescribed a priori as high order polynomial equations through a user-defined function. The rotor noise is predicted using Fluent Acoustic module based on the Ffowcs-Williams and Hawking's equations. Methodology is verified using HART II experimental setup and data which includes flapping, pitching, lead-lag motion and elastic torsion for each rotor blade. Individually defined blade motion is found critical for an accurate acoustic prediction based on the obtained CFD calculation. The present predictions compare very well and performs better than other previous CFD analysis both for minimum noise and baseline case at maximum sound pressure level (SPL) of HART II data, even with meshes of 7-8 million cells rather than tens of millions usually needed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A new cannabis addiction screening approach is developed based on the use of Machine Learning (ML) alongside with psychological and cognitive assessment tests. The Hospital Anxiety and Depression (HAD) test is used to determine the Absence of Anxiety and Depression “No Disorder” or the presence of “Anxiety Only”, “Depression Only”, and both “Anxiety and Depression”. These features are considered to evaluate the psychological effects of cannabis use. In addition to that, the Montreal Cognitive Assessment (MoCA) test is chosen as a feature to assess the cognitive state of the participants. Also, the Age of First Cannabis Use (AFCU) is included as a feature to incorporate participants with no prior cannabis use alongside with those who have used cannabis before. The portion of participants with prior experience consuming cannabis comprises a subset containing passive users and a subset of users that have developed cannabis addiction. This 6-month study was conducted in Marrakech, Morocco in a center affiliated to the National Association of Drug-Risk Reduction of Morocco known as RdR-Maroc with the participation of 146 subjects. The participants in this study are grouped into two groups of 73 participants each. Both case and control groups were clinically assessed by a professional. In this paper, the classical statistical data analysis for the AFCU (M=15.6; SD=2.4), MoCA (M=25.0; SD=2.4), and HAD (58 cases with no disorder, 88 cases with disorder) failed to separate between the two classes. Also, the feature selection for modeling is performed using Spearman correlation, Kendall correlation, and the Odds Ratio (OR). These statistics showed that the selected features were associated to addiction except for “Anxiety Only”. Moreover, ML models such as Logistic Regression (LR), Support Vector Machine (SVM), Artificial Neural Network (ANN), kth-Nearest Neighbor (KNN), and Decision Tree (DT) were used to classify participants into two categories (Addict vs. Non-Addict) based on the selected features mentioned earlier. The Receiver Operating Characteristic (ROC) curve is used to overview the quality of the models and showed that they all captured the nonlinearities underlined in the data. On the other hand, the Area Under the Curve (AUC) allowed the ranking of these models and indicated that the SVM model outperformed all other models with an AUC of 0.97. After that, the SVM model was compared to the Cannabis Use Disorder (CUD) based screening method issued by the fifth edition of the Diagnostic and Statistical Manual of mental disorders (DSM-5). The SVM model's accuracy of 96.6 % outperformed the CUD questionnaires accuracy of 87.7 %. The validity of the proposed approach was investigated where the SVM model presented high validity characteristics (sensitivity=1, specificity=0.93) compared to the CUD questionnaire (sensitivity=0.75, specificity=1). Hence, the proposed approach provided satisfactory results compared to current adopted CUD based screening test. Our findings expand current research on the development of simple and powerful tools for cannabis addiction screening with the purpose of early detection in order to establish preventive and therapeutic strategies that could potentially mitigate the prevalence of cannabis addiction.

In this study, the thermal performance of a jacketed heat exchanger with a stirrer was experimentally and numerically investigated under different jacket side water inlet temperature and flow rate conditions. In the numerical study, a three-dimensional computational fluid dynamics (CFD)model of the heat exchanger was generated and the analyzes were performed with the ANSYS-Fluent software package. In addition, a stirrer was added to both the experimental and the numerical study to obtain the effects of the stirrer on the temperature and velocity values of the water in the tank. It was seen that the results of the analyzes performed under similar conditions to the experimental study were in good agreement with the experimental study. It was concluded that the effect of the flow rate decreases with increasing inlet temperature. When the stirrer was activated and the flow rate was increased from 0.5 to 2.5 l/min in 30, 40, and 50°C inlet temperature conditions, the time to reach the target temperature inside the tank decreased from approximately 1600 to 900, from 2500 to 1350, and from 4900 to 1400, respectively. In general, it was observed that the effect of the stirrer increased with increasing inlet temperature in all flow rate conditions.

In this study, experimental and numerical analysis studies of a submersible pump performance were carried out. First of all, the performance tests were carried out with a four-stage pump with the most efficient operating point of 140 m³/h in the test setup in the company. Then, numerical studies were made for the four-stage model of the same pump with Computational Fluid Dynamics. In the study, the head and efficiency values of the pump were calculated for different flow rates. In addition, the velocity and pressure changes in the pump section are presented visually for the numerical analysis results. As a result, at 140 m³/h flow rate, which is the optimum operating point of the submersible pump, the difference between the experimental and numerical results is about 3.15% in head, while it is around 9% in efficiency. The results brought to the literature are of the quality to be used for validation in commercial and academic studies due to the similarity of efficiency and head curves. [ABSTRACT FROM AUTHOR]

Missile aerodynamic design studies require flight control of an aircraft that passes through diverse flight regimes with extreme maneuvering requirements, using a minimal control surface set. These challenging goals are achieved typically using a simplified pre-design tool among thousands of body-fin alternatives. Alternative geometries found at this stage are then transferred to the computational domains, and CFD analyses are conducted to ensure aerodynamic performance. However, this new stage involves a costly and time-consuming preprocessing workload. For this reason, the number of missile geometries transferred from the pre-design stage is very limited. Considering that pre-design tools cannot provide sufficiently precise results, it is seen that this transfer mechanism should be replaced with a new method that is less costly than traditional workflow but more precise than pre-design tools. This study presents a new software tool that uses Missile DATCOM design terminology to generate solution domain and computational mesh automatically. This technology generates a remarkably high-quality structured mesh around the missile geometry. Fin control angles can be applied, and CFD analyses are performed at desired flight conditions. CFD analyses are performed using an in-house compressible CFD tool, and a good match with the experimental results is observed. [ABSTRACT FROM AUTHOR]

In this study, heat transfer characteristics of helical heat exchangers were investigated under steady state conditions. In the experiments, the inlet temperature of the cold water into the heat exchanger was set as 20 °C and the hot water temperature was set as 50 °C. The flow rates of cold water were set as 2 - 3 - 4 and 5 l/min. The outlet temperature of the cold water from the heat exchanger was measured and the inside Nu number was calculated. For numerical study a three dimensional model of the heat exchanger was designed. Numerical analysis was carried out to determine the thermal properties and velocity contours in the heat exchanger using a computational fluid dynamics software program package (Fluent 18.2). The inside Nu number and the outlet temperature of the water from the heat exchanger were compared with the data recorded in the experimental study. The computational fluid dynamics results were obtained to be in agreement with the experimental results. [ABSTRACT FROM AUTHOR]

In this article; computer-aided design and prototype production studies carried out to increase the efficiency of a double eccentric butterfly valve, reduce its carbon footprint and provide energy savings were included. With the prototype developed by computational fluid dynamics (CFD/HAD) and finite element method (FEA/SEA), a product with increased disc strength, optimized valve weight, and reduced energy losses by minimizing resistance to flow has been designed. With the intensive use of simulation techniques, the competitive conditions of environmentally friendly and highly efficient valves have been improved and an innovative product has been introduced to the market. For strength and flow optimizations, the optimized valve design was carried out by analyses with the ANSYS (Fluent / CFX and Mechanical) program in the computer environment. A prototype has been developed that can operate at high flow coefficients and has the lowest energy losses in the industry with a different valve design. With the Solidworks sustainability report, the carbon footprint and total consumed energy values has been carried out. [ABSTRACT FROM AUTHOR]

La prise en charge hospitalière à domicile des nouveau-nés se développe en France ces dernières années, répondant aux demandes des familles et s'intégrant dans l'évolution des soins de néonatologie, centrés sur l'enfant et sa famille. Des nouveau-nés encore immatures et non autonomes sur le plan de l'alimentation peuvent continuer leur hospitalisation à domicile, soutenus par des équipes spécialisées en lien avec une unité de néonatologie. L'hospitalisation à domicile (HAD) permet de raccourcir le séjour initial et le temps de séparation des familles, de mieux accompagner la sortie et de diminuer l'anxiété parentale, de soutenir l'allaitement maternel et le développement des enfants. L'évolution du cadre légal français avec, d'une part, les HAD avec la mention pédiatrique « enfant de moins de 3 ans » ayant une convention avec une unité de néonatologie et, d'autre part, le dispositif expérimental de soins de néonatologie à domicile, par les équipes de néonatalogie, vont permettre de proposer cette alternative à l'hospitalisation traditionnelle à davantage de familles sur le territoire. In recent years, neonatal home care in France has undergone development in response to family demands and as part of the evolution of neonatology towards family-centered care. Infants who are still immature and require neonatal care such as tube feeding (not independent in terms of food) can continue their hospitalization at home, assisted by specialized teams in collaboration with a neonatology unit. Neonatal home care makes it possible to shorten the initial hospital stay and reduce parent-infant separation, better prepare the family for discharge and reduce parental anxiety, support breastfeeding and child development. The French legal framework changed recently. On the one hand, a neonatal home care unit can obtain a pediatric mention "child under 3 years old". It can admit newborns if it has an agreement with a neonatology unit. On the other hand, neonatology teams are allowed to take care of their patients at home in a new experimental setting. This will make it possible to offer this alternative to traditional hospitalization to more families in the area. [ABSTRACT FROM AUTHOR]

Modelling of transition from the laminar to turbulent flow became a hot topic due to recent developments in renewable energy, UAV technologies and similar aerospace applications. The transition from laminar flow to turbulence is challenging to model in CFD analysis. The drag is overestimated if the transition is neglected in CFD solutions by assuming the flow is fully turbulent. This results in missing the fundamental characteristics of the flow and inaccurate predictions of the flow field. The most popular transition models are Menter's models applied to the SST turbulence model and the Baş-Çakmakçıoğlu (BC) transition model applied to the Spalart-Almaras model. We have focused on Menter's simpler but more popular γ model and Baş Çakmakçıoğlu models. The γ model relies on the local turbulence intensity, which makes applying the model challenging in external flows. This difficulty stems from the complex relationship between turbulence decay and transition onset. BC transition model utilizes the free stream turbulence intensity. Both models are verified using the Klebanoff and ERCOFTAC flat plate cases and several 2D external flow cases. Skin friction coefficient results are compared to experimental data. Results show that both models predict transition very similarly. BC model is computationally cheaper and easier to implement than the γ model. Also, γ model suffers from boundary conditions ambiguity. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Research & Development / Revista de Investigación & Desarrollo is the property of ECORFAN-Mexico S.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In a cold plate low thermal resistance thus high heat transfer rate and also low pressure drop is desired. In this study, performances of three liquid cold plates with different configurations are investigated for the thermal regulation of li-ion battery cells in electric vehicle applications. The outer dimensions of the cold plates are kept identical in order to use the cold plates in the same battery module under series, parallel and series-parallel configurations. The performances of the cold plates are investigated by using Computational Fluid Dynamic (CFD) tools. ANSYS Fluent commercial software is used to calculate the flowfield and the thermal field inside the cold plates for various flowrates. The performances of the cold plates are obtained by 3D simulations that solve Navier-Stokes, energy and continuity equations in a steady manner. The flow is assumed to be laminar for all the cases since calculated Reynolds number stay in laminar flow limits. The results show that the pressure drop of the coolant liquid of parallel flow arrangement is significantly lower than the serial arrangement. However, high thermal resistance and low uniformity of the temperature through the cold plate is observed compared to the serial case, as expected. As a result, series-parallel configuration results show that the trade-off between pressure drop and heat transfer rate can be optimized by applying a serpentine shape while keeping the flow arrangement as parallel as possible and increasing the length of the cross channels.

Abstract The SARS-CoV-2 virus has been raging globally for over 2 years with no end in sight. It has become clear that this virus possesses enormous genetic plasticity, and it will not be eradicated. Under increasing selective pressure from population immunity, the evolution of SARS-CoV-2 has driven it towards greater infectivity, and evasion of humoral and cellular immunity. Omicron and its expanding army of subvariants and recombinants have impaired vaccine protection and made most antibody drugs obsolete. Antiviral drugs, though presently effective, may select for more resistant strains over time. It may be inevitable, then, that future SARS-CoV-2 variants will be immune to our current virus-directed countermeasures. Thus, to gain control over the virus, we need to adopt a new paradigm in searching for next-generation countermeasures and develop host-directed therapeutics (HDTx) and host-directed antivirals (HDA). Different from the virus-directed countermeasures, HDTx and HDA may offer variant agnostic treatment to reduce the risk and severity of infections. In addition, they may exert more uniform effects against the genetically diverse SARS-CoV-2 quasispecies, thereby diminishing the risk of selecting resistant variants. Some promising HDTx and HDA approaches are summarized here.

In this study, the thermal performance of a jacketed heat exchanger with a stirrer was experimentally and numerically investigated under different jacket side water inlet temperature and flow rate conditions. In the numerical study, a three-dimensional computational fluid dynamics (CFD)model of the heat exchanger was generated and the analyzes were performed with the ANSYS-Fluent software package. In addition, a stirrer was added to both the experimental and the numerical study to obtain the effects of the stirrer on the temperature and velocity values of the water in the tank. It was seen that the results of the analyzes performed under similar conditions to the experimental study were in good agreement with the experimental study. It was concluded that the effect of the flow rate decreases with increasing inlet temperature. When the stirrer was activated and the flow rate was increased from 0.5 to 2.5 l/min in 30, 40, and 50°C inlet temperature conditions, the time to reach the target temperature inside the tank decreased from approximately 1600 to 900, from 2500 to 1350, and from 4900 to 1400, respectively. In general, it was observed that the effect of the stirrer increased with increasing inlet temperature in all flow rate conditions. [ABSTRACT FROM AUTHOR]

The aim of this study is to refine a cognitive model forthe takeover in highly automated driving. The focus lieson the impact of objective complexity on the takeoverand resulting outcomes. Complexity consists of variousaspects. In this study, objective complexities are di-vided into the complexity of the non-driving-related task(no-task, listening, playing, reading, searching) and thetraffic complexity (relevant vehicles in the driving envi-ronment). The impact of a non-driving related tasks’complexity on the takeover is evaluated in empiricaldata. Following, the cognitive model is run through sit-uations of different traffic complexities and compared toempirical results. The model can account for empiricaldata in most of the objective complexities. Additionally,model predictions are tested on significant variations indifferent complexities until the action decision is made.In more complex traffic conditions, the model predictslonger times on different processing steps. Altogether,the model can be used to explain cognitive mechanismsin differently complex traffic situations.

This study aimed to reveal predictions about how the total pressure difference occurring in front of and behind the radiator in the cabin generator set affects the operating temperature of the generator set in the absence of sufficient thermal information. After the cabin design, numerical analyses were made for three louvers with different depth dimensions, as that they significantly affect the total pressure difference. It was found the most suitable louver depth as a result of numerical analysis. Flow analyses were created by using ANSYS FLUENT 19.2 software as a numerical study of the generator cabin. Numerical analyses haven't been created based on temperature since thermal information was not adequately available. As a result of numerical studies, a total pressure difference of 139.25 Pa has occurred. This pressure difference value is 14.25 Pa higher than the pressure difference value allowed by the radiator of the 1104C-44TAG2 engine. Firstly, the generator set was manufactured. Then it was implemented experimental studies with the HIOKI test device to determine how the pressure difference value of 14.25 Pa affects the temperature of the generator set. The result shows that the pressure difference of 14.25 Pa reduces the maximum ambient temperature at which the generator can operate by 3.9°C as a result of the experimental studies [ABSTRACT FROM AUTHOR]

The rapid development of technologies using renewable energy sources is paving the way for new solutions to meet the increasing energy and power needs of the industry. This study investigated the thermal and flow properties of a solar air heater used in food drying in the industry. The optimum efficiency of the solar air heater (SAH) was investigated for two different absorber plate lengths (1400 mm and 1820 mm). The energy and exergy efficiency values of both collectors were compared. ANSYS FLUENT 18.1 was used as a computational fluid dynamics (CFD) numerical analysis program in the study. Analyzes were performed at three different mass flow rates as 0.038-0.054-0.070 kg/s and 3-dimension (3D), respectively. For the accuracy of the CFD analysis, the experimental results with a mass flow rate of 0.038 kg/s were compared with the analysis results. Friction coefficients were calculated from the pressure drop obtained from the analysis. Temperature, velocity, and pressure distribution variations were shown for different times of the day. The highest thermal efficiency was realized at 13:00 at a mass flow rate of 85% and 0.070 kg/s. The thermal efficiency of the collector has increased with higher flow rates. Although the increase in the mass flow through the collector decreased the outlet temperature, the valuable energy amount increased. This study demonstrated that different mass flow rates and absorber plate size significantly affect the thermal efficiency of SAH. [ABSTRACT FROM AUTHOR]

In order to reduce the storage costs of fruits in cold stores, more products are placed than necessary. Since homogeneous speed and temperature distribution cannot be achieved due to overloading in cold stores, partial losses and quality reductions occur in products. Since the initial investment costs of methods such as using ducts and fans recommended for homogeneous air and temperature distribution are high, they are not used to a large extent. In this study; In order to analyze and improve the air and temperature distribution in the cold store, first of all, temperature and velocity measurements were made at certain points in a cold store filled with Granny Smith apples. Deflector panels that are placed at different angles are used to provide homogeneous velocity and temperature distributions. Using these measurements, the CFD model was created and validated. ANSYS-Fluent program was used for CFD analysis. With the analyzes made on the model, the problematic points in the air and temperature distribution were determined and it was seen that the panel with a vertical angle of 63° gave the best results among the deflector panels placed at different angles to eliminate these problems. Since the proposed solution is economically extremely cost-effective, it is anticipated that it can be applied to all cold storage regardless of size, location, and stored product. As a result of this practical, easy, and economical application, both product losses and energy consumption will be reduced, and the products will be preserved for a longer period of time while maintaining their quality. [ABSTRACT FROM AUTHOR]

The increase in global energy consumption and carbon dioxide emissions increase the interest in renewable energy sources. Solar energy is at the forefront of renewable energy sources, and the decrease in cell efficiency due to various reasons during operation is an obstacle to this technology. Increasing the temperature of photovoltaic cells during operation causes a decrease in cell efficiency. Control of photovoltaic cells temperature is crucial in terms of both prolonging the economic life of the cells and increasing the efficiency of the system. The effect of the evaporator inlet and outlet position of the fluid on the heat transfer is known, but this effect was not examined in the studies carried out to increase the efficiency of the PV-T (photovoltaic–thermal) system. In the current study, the system efficiency parameters and COP (coefficient of performance) values of a PV-T evaporator cooled by forced air circulation were investigated by CFD (computational fluid dynamics) analysis. The analyzes were carried out in a single array for three different flow rates (0.0125 kg/s, 0.0250 kg/s, 0.0500 kg/s) and nine different evaporator inlet-outlet positions (CC, CL, CR, RC, RL, RR, LC, LL, LR), constant radiation of 1000 W/m². It was determined that there is a total efficiency difference of over 20% and an overall COP difference of over 25% between the best and worst inlet-outlet positions. The highest total and thermal efficiency were obtained for the RR condition, and the highest electrical efficiency was obtained for the LR condition but in the long-term, the highest efficiency can be achieved with the LC design. In the study also the highest COP values were calculated for the CL condition and the worst COP values for the RR condition. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study the effects of turbulence kinetic energy structures formed during flow and particles of different diameters and different flow velocities in the air in different regional areas on aerodynamic performance characteristics in NACA 0012. Single and two phase fluid flows were worked out by using Ansys Fluent Computational Fluid Dynamics (CFD) code. Computational results obtained from Ansys Fluent CFD code for pure air and the air containing sand particles were compared with numerical values gained in the literature for validation. Results obtained from the numerical tests demonstrate good agreement with the value in the literature. These results indicate the turbulence kinetic energy value occurred in the tail region of the airfoil increases with the increase in the angle of attack and shifts towards the upper region of the airfoil at high attack angle. Moreover, the upper region of the airfoil at high attack angle becomes larger at low Reynolds numbers due to viscous effects. The drag and lift coefficients obtained in the numerical tests of the airfoils and in the experimental tests in the wind tunnel will differ from the values in the application area. Because, in the operation of airfoils in different regional environments, there are always particles of various concentrations and diameters in the air. In this case, the drag coefficient increases and the lift coefficient decreases. [ABSTRACT FROM AUTHOR]

Çağdaş hukuk sistemlerinde kanunların genelliği ile belli bir kişiyi hedef almayan, özel ve ârizî bir durumu değil önceden belirlenmiş, soyut, kapsadığı herkese hitap eden hükümler kastedilmektedir. Bu açıdan bakıldığında kanunun genelliği kanun önünde herkesin eşit olması ile aynı şeyi ifade eder. Ancak çağdaş ceza hukukunda eşitlik ile nispi eşitlik anlaşılıp her şeyi ile eşit olan kimseler arasındaki bir eşitlikten bahsedilebilir. Eşit olmayanların aynı cezai müeyyidelere muhatap olması bu eşitlik anlayışına ters bir durumu meydana getirir. İslam ceza hukukunda kanun önünde eşitlik söz konusu olduğunda bunun cezanın ilgili olduğu hak grubu ile yakından ilgisi olduğu gibi ceza türü ile de ilgisi vardır. Hakların Allah hakkı ve kul hakkı diye iki grupta mütalaa edilmesi sebebiyle kul hakkına ilişkin olan cezalarda eşitlik ilkesine riayet edildiği söylenebilir. Bu alanda da her ne kadar mezhepler arasında farklılık bulunsa da Hanefî mezhebi eşitlik ilkesinin önemli savunucularından birisidir. Ceza hukukunun genel ilkeleri bağlamında İslam ceza hukukunda umumiliğini konu edinen bu çalışma, İslam ceza hukukunda cezalarda umumilik ilkesinin işletilip işletilmediğini, umumiliğe aykırı hükümlerin bulunup bulunmadığını belirlemeyi amaçlamaktadır. Bu çalışmada öncelikle ceza hukukunda genellik ile neyin kastedildiği modern ceza hukuklarından araştırılacak, akabinde İslam ceza hukukunda had, kısas ve ta‘zir ana başlıkları altında cezalarda umumiliğin olup olmadığı değerlendirilecektir.

Otomotiv sektöründe artan teknoloji kullanıcılara daha gelişmiş konfor koşulları sunmaktadır. Otomobil koltuklarında ısıl konfor açısından arzu edilen seviyeler kış koşullarında koltuk ısıtma sistemleriyle sağlanırken yaz koşullarında koltuk soğutma sistemleri kullanılarak sıcak koltuk yüzeylerinin soğutulmasıyla sağlanır. Bu çalışmada otomobiller için yeni bir koltuk soğutma sistemi tasarımı yapılmış ve prototipi üretilmiştir. Geliştirilen bu aktif havalandırmalı koltuk sistemi taşıt iklimlendirme sistemi tarafından şartlandırılan iç ortam havasını kullanıyor olup istenildiğinde ilave bir soğutucu ünite ile daha etkin bir soğutma da sağlayabilir. Ayrıca geliştirilen bu koltuk tasarımının oturma bölgesi üç-boyutlu (3D) Hesaplamalı Akışkanlar Dinamiği (HAD) analizleri yapılmak üzere modellenmiştir. Üretilen ve modellenen koltuklarla hem otomotiv üretici standartlarına hem de literatürde yer alan çalışmalara uygun olacak koşullar altında deneysel ve sayısal çalışmalar gerçekleştirilmiştir. Koltuk yüzeyine homojen bir hava dağılımı için eklenen gözenekli yapı bölgesinin sıcaklığı 60. saniyede 25°C’ye düştüğü ve diğer yüzeylerin 50°C civarında olduğu görülmüştür. HAD analiz sonuçları incelendiğinde ise fan vasıtasıyla sağlanan hava akımı yaklaşık 2 m/s hızla koltuk modeline girmiş ve gözenekli bölgede 4.5 m/s’ye kadar yükselmiştir. Deneysel ve sayısal çalışma sonuçlarının uyum içinde olduğu gözlenmiştir. Fan etkisinin devre dışı bırakıldığı ve sadece doğal taşınımla soğumanın gerçekleştiği analiz sonuçları fanlı sistemlerin sonuçları ile karşılaştırıldığında ise aktif koltuk soğutma sistemiyle koltuk yüzeyinde yaklaşık 8°C’ye kadar daha düşük değerlerinin elde edildiği görülmüştür. Geliştirilen bu sisteminin özellikle sıcak yaz koşullarında ısıl konfor şartlarının sağlanmasına katkı sağlayacağı düşünülmektedir.

Copyright of Mutefekkir, Faculty of Islamic Sciences is the property of Aksaray University, Faculty of Islamic Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the performance of a portable air cleaner, which is used to clean the air of a room with a person sitting in it, was investigated. The effects of different blowing angles and flow rates from the air supply vent on the device cleaning performance were investigated. In this context, air age and clean air delivery rate (CADR) parameters were calculated numerically. Randomly distributed particles in the room were tracked using the discrete phase model (DPM) and the relationship of pollutant concentrations with CADR and air age was examined. It has been seen that the blowing angle is an important parameter along with the flow rate. Moreover, it was concluded that the air age approach can be used to determine the performance of air cleaning devices. It has been found that the air cleaning device capture more than half of the particles in the environment, while the remaining particles are captured by other room surfaces. [ABSTRACT FROM AUTHOR]

Türkçe’ye Farsça’dan geçmiş olan namaz, bir fıkıh terimi olarak belirli rükün ve fiillerle yapılan ibadet için kullanılmaktadır. Şekil ve mahiyeti farklı olsa da bütün ilahi dinlerde var olduğu bilinen namaz bugünkü şekliyle hicretten yaklaşık bir buçuk yıl önce Miraç gecesinde farz kılınmıştır. Namazın, ayet ve hadislerde imandan sonra ikinci sırada zikredilmesinden hareketle imandan sonra dinin en büyük ve en önemli rükünlerinden biri olduğu ifade edilmektedir. Ayrıca diğer ibadetlere kıyasla önemine binaen namaz, dinin direği olarak nitelendirilmiştir. İslam, kulların menfaatini sağlamayı ve onlardan zararı gidermeyi gaye edinmiş, insanların din, can, akıl, nesil ve mallarının korunmasını güvence altına almıştır. Mekâsid-ı hamse olarak bilinen bu hususların başında dinin korunması yer almaktadır. Fakihler, ceza hükümleri bakımından namaz kılmama suçunu dinin korunması bağlamında ele alarak değerlendirmiş ve namazı terk edenler hakkında farklı görüşler ileri sürmüşlerdir. Bunun için de namaz kılmayanları “namazın farz olduğunu inkâr edenler” ve “inandığı halde namaz kılmayanlar” şeklinde ikili bir ayrıma tabi tutmuşlardır. Namaz “zaruriyyât-ı din”den yani her Müslümanın bilmesi gereken temel bilgilerden olduğu için inkâr edenin kâfir olacağı konusunda fakihler arasında icma bulunmaktadır. Bundan dolayı fakihler, namazın farziyetini inkâr edenlere verilecek cezayı irtidâd kapsamında değerlendirmişlerdir. Bir istisna olarak İslam’a yeni girdiği için bilgisizlikten kaynaklı veya şehirden uzak yerlerde yaşamasından dolayı namazın farz olduğu hakkında bilgisi olmayanın, namazın farz olduğunu inkâr etmesi mazeret kapsamında değerlendirilmiş ve küfürle itham edilmemiştir. Hanefîler’e, mezhepte tercih edilen görüşe göre Şâfiîler ile Mâlikîler’e ve Hanbelî mezhebinde Ahmed b. Hanbel’den yapılan bir rivayete göre ihmal veya tembellikten dolayı namazı terk eden küfürle itham edilmez. Şâfiîler’de bir veche, Mâlikîler’de bir kavle ve bazı selef âlimlerine göre de inandığı halde namaz kılmayan kişi dinden çıkmış sayılmaktadır. Hanbelî mezhebinde Ahmed b. Hanbel’den aktarılan bir diğer rivayete göre ihmal ve tembellikten dolayı namazı terk eden kişi mürted olur. Fakihler, farz olduğuna inandığı halde namaz kılmayan kişinin öncelikli olarak tövbe etmeye davet edilmesi gerektiği, tövbe edip namaz kılması halinde serbest bırakılacağı görüşünde ittifak etmektedirler. Tövbe ettikten sonra namazı evinde kılacağını söyleyen kişi serbest bırakılır ve namaz kılıp kılmadığı takip edilmez. Tövbe etmeyip namaz kılmamaya devam etmesi durumunda kişiye verilecek cezanın ta’zir veya had cezası olması hakkında fakihler arasında görüş farklılığı bulunmaktadır. Hanefîler, zekât, oruç ve hac gibi ibadetlerin terkinden dolayı had kapsamında ölüm cezası verilmediği gibi namaz için de aynı durumun geçerli olduğu görüşünü savunmaktadırlar. Hanefîler’e göre namaz kılmayan mürted olmamakla birlikte büyük günah işlemiş sayılmaktadır. Onlara göre bu kişiye verilecek ceza ta’zir cezasıdır. Mâlikîler’e, Şâfiîler’e ve Hanbeli mezhebinde Ahmed b. Hanbel’den yapılan bir rivayete göre inandığı halde namaz kılmayan Müslüman olmakla birlikte namaz kılmadığı için had suçu kapsamında öldürülür. Bazı Mâlikî fakihlere ve Ahmed b. Hanbel’den yapılan bir diğer rivayete göre namaz kılmayan mürted olup küfre düştüğü için öldürülür. Onlara göre namaz kılmayana verilen ölüm cezası irtidâd kapsamında had cezasıdır. Bu çalışmada sünnî fıkıh mezhepleri ekseninde önce namazın farz olduğunu inkâr edenler hakkındaki görüşler incelenecek, ardından inandığı halde namaz kılmayanlar hakkındaki görüşlere yer verilecektir. Daha sonra namazı kılmama suçunun ispatı, suçun ispatını takiben kişiye düşünme ve tövbe etmesi için verilecek sürenin tespiti ve cezanın nasıl infaz edileceğine dair görüşler ele alınacaktır. Çalışma elde edilen bulguların değerlendirildiği sonuç bölümüyle tamamlanacaktır.

Copyright of Journal of Engineering & Architectural Faculty of Eskisehir Osmangazi University / Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi is the property of Eskisehir Osmangazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Dokuz Eylul University Muhendislik Faculty of Engineering Journal of Science & Engineering / Dokuz Eylül Üniversitesi Mühendislik Fakültesi Fen ve Mühendislik Dergisi is the property of Dokuz Eylul Universitesi Muhendislik Fakultesi Fen ve Muhendislik Dergisi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the method which is going to be followed during the calculations of hydrodynamic coefficients of DARPA SUBOFF submarine in manoeuvering simulations was determined by static drift tests simulations. Accurate prediction of hydrodynamic coefficients which are used in underwater vehicle manoeuvers is related with mesh and turbulence models used in solutions. The commercial software ANSYS Workbench was used in the study. The proper mesh size selection was accomplished by using Grid Convergence Index (GCI) which is based on Richardson Extrapolation method. The discretization error band around the solutions obtained for three different mesh sizes were estimated with Spalart Almaras turbulence model. In addition, these solutions were compared with the experimental results which were carried out at 14 million Reynolds number at 0 to 18 degrees drift angles. It was observed that numerical results get closer to the experimental results as the number of elements increases. After selection of suitable mesh, the options of turbulence models were investigated by repeating the analyses with Realizable k-e and SST k-1 models. At the end of study, one-equation Spalart Almaras turbulence model is evaluated as adequate for practical applications upto 18 degrees of drift angle. For the applications at high drift angles, two-equation SST k-turbulence model is recommended to be re-assessed. [ABSTRACT FROM AUTHOR]

Human beings are subject and object of law with their rights, actions or inactions throughout his life. For this reason, the law has evaluated human beings from the time they fall into the mother's womb and has established provisions in accordance with their dispositions. Since Roman Law, legal systems have accepted "minority" as a period that needs to be evaluated differently. This situation has shown its effect especially on the validity of the judgment and legal acts. In the study, the concepts of distinctive and disqualification, their nature and whether the impotent minor is liable or not, the validity of his legal dispositions, the situation of the impotent m inor in the face of practices such as hadd, qisas, ta‘zîr, compensation, ta’dib in terms of punishment, legal capacity, oath, testimony, confession, etc. ıssues such as whether there will be or not. As a result of this study, it is aimed to have more information about childhood and especially about the period of grace, to know its rights and responsibilities and to reveal some issues in accordance with the situation. [ABSTRACT FROM AUTHOR]

Copyright of SDU Journal of Engineering Sciences & Design / Mühendislik Bilimleri ve Tasarım Dergisi is the property of Journal of Engineering Sciences & Design and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hidrolik yapılar ve hidrolik yapıların farklı öğeleri için, hidrolik hesaplamalar çeşitli deneysel çalışmalara başvurarak yapılabilmektedir. Yapılan deneysel çalışmalar ile hidrolik hesaplamalar desteklenmeye çalışılmaktadır. Ancak, deneysel çalışmaların maliyetli olması ve uzun bir zamana yayılması sebebi ile, 3 boyutlu simülasyon programları tercih edilmektedir. Hidrolik yapılar için, hesaplamalı akışkanlar dinamiği yöntemi (HAD) ile çalışan programların kullanılmaya başlanması ile deneysel çalışmalara olan ihtiyaç gittikçe azalmıştır. Sonlu elemanlar, sonlu hacimler gibi sayısal yöntemlerin de katkısıyla, akış ayrıntılı bir şekilde incelenebilmektedir. Bu çalışma, Isparta’da bulunan, içme ve kullanma suyu ihtiyacını karşılamak için yapılan, Darıderesi II Göleti’ne ait dip savak yapısı için yapılmıştır. Ölü hacim üzerindeki suyun mansaba iletilmesini sağlayan dip savak yapısında türbülanslı ve laminer akım halleri incelenmiştir. Dip savak yapısı, sonlu elemanlar ile çalışan ANSYS programı Fluent modülü ile modellenmiştir. Geliştirilen 3 boyutlu modele ait, kesitte meydana gelecek olan toplam basınç, hız büyüklüğü ve boruya ait kesme gerilme değerleri incelenmiştir. Türbülanslı akım hali için elde edilen kinematik büyüklükler hidrolik şartnamede verilen sınır şartlarına daha yakın değişimler göstermiştir. Dip savak yapılarında laminer akım hali yerine türbülanslı akım halinin seçilmesi daha uygun bulunmuştur.

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Automated driving functions are expected to increase both the safety and ride comfort of future vehicles. Ensuring their functional safety and optimizing their performance requires thorough testing. Costs and duration of tests can be reduced if more tests can be performed numerically in a feasible simulation framework. This simulation setup must include all subsystems of the autonomous vehicle, which significantly interact with the system under test. In this paper, a modular model chain is presented, which is developed for testing systems with an impact on vehicle motion. It includes trajectory planning, motion control, and a model of the vehicle dynamics in a closed loop. Each subsystem can easily be exchanged to adapt the model chain with respect to the simulation objectives. As a use case, the testing of an active suspension control system is discussed. It is designed directly for use in autonomous cars and uses inputs from the vehicle motion planning subsystem for planning the suspension actuator motion. Using the presented closed-loop model chain, the effect of different actuator control strategies on ride comfort is compared, such as curve tilting. Furthermore, the impact of the active suspension system on lateral vehicle motion is shown. [ABSTRACT FROM AUTHOR]

Güneş kurutucu sistemi, ileri bir doğal güneş kurutma teknolojisi olarak geniş alanlardada kullanılmaktadır. Bu çalışmanın amacı; atık boya çamurunun yönetimi sürecinde güneşle kurutmayı alternatif bir proses olarak incelemektir. Çalışmada faz değiştirme malzemesi olarak parafin içeren bir güneş kurutma sistemi tasarlanarak kurutma verimliliği araştırılmıştır. Kurutulan çamur kalınlığının düşük olması sebebiyle kurutma sırasında karıştırmanın etkisi gözlenememiştir. Kurutma işlemi 8 saatte 1849 Wh/m2 kümülatif güneş radyasyonu ile yapılmıştır. İç sıcaklık, nem, güneş radyasyonu, zaman, çamur kütlesi ve hacmini azaltmanın yanı sıra kurutucuda kullanılan ekipmanlar ısı transferini güçlendirmek için önemli faktörler olarak belirlenmiştir. Sistemde fan ile oluşturulan hava sirkülasyonunun yetersiz olduğu hesaplamalı akışkanlar dinamiği (HAD) ile tespit edilmiştir, ve simülasyon modeli kurutma sisteminin optimize edilmesi için kullanılmıştır. Gözenekli yapının oluşumu, bir tarama elektron mikroskobu (SEM) kullanılarak kurutulmuş çamurda gözlenmiştir. Atık boya çamurunun yönetiminde güneş kurutucusunun geliştirilmeler sonrası kullanılabilecek bir alternatif olduğu sonucuna varılmıştır.

Bu çalışmada sıcak bir plakanın çarpan jet akışla soğutulmasının ısı transferi ve akış karakteristikleri hesaplamalı akışkanlar dinamiği yöntemi ile sayısal olarak incelenmiştir. Sıcak plakanın aynı yükseklikteki düz, zikzak, yamuk ve dikdörtgen kesitli geometrileri için ikili nozul sistemi kullanılarak türbülanslı çarpan jet akış ile soğutulması durumunda ısı transferi ve hidrolik performanslar karşılaştırılmıştır. Hesaplamalarda çalışma akışkanı olarak hava kullanılmış olup, taşınımla gerçekleşen ısı transferi performansının analizi için ortalama ve yerel Nusselt (Nu) sayılarının dağılımı elde edilmiştir. Hidrolik performans için pompalama gücü değerleri karşılaştırılmıştır. Türbülanslı çarpan jet akış için k-ε türbülans – duvar yakın modelinin kullanılmıştır. Elde edilen sonuçlara göre, yamuk kesitli plakanın en yüksek ısıl performansa sahip olduğu ve taşınımla gerçekleşen ısı transfer hızı aynı şartlarda düz plakadan yaklaşık %52,2 daha yüksek olduğu belirlenmiştir. Termo-hidrolik performans açısından Nusselt sayısı/Pompalama Gücü oranı hesaplanmış ve en düşük performansın basınç farkının en yüksek olmasından dolayı dikdörtgen kesit için oluştuğu gözlemlenmiştir. Bununla birlikte yerel Nusselt sayılarının dağılımına bakıldığında, nozulların çarptığı noktalarda en yüksek değerleri alıp çıkış kısımlarına doğru azaldığı belirlenmiştir. Çarpan jetler kullanılarak soğutma işlemi yapılan sıcak plaka yüzey kesit şeklinin taşınımla gerçekleşen ısı transferini önemli ölçüde arttırdığı görülmüştür.

BackgroundCerebrospinal fluid (CSF) neurofilament light chain protein (NFL) is a sensitive marker of neuronal injury in a variety of neurodegenerative conditions, including the CNS dysfunction injury that is common in untreated HIV infection. However, an important limitation is the requirement for lumbar puncture. For this reason, a sensitive and reliable blood biomarker of CNS injury would represent a welcome advance in both clinical and research settings.MethodsTo explore whether plasma concentrations of NFL might be used to detect CNS injury in HIV infection, an ultrasensitive Single molecule array (Simoa) immunoassay was developed. Using a cross-sectional design, we measured NFL in paired CSF and plasma samples from 121 HIV-infected subjects divided into groups according to stage of their systemic disease, presence of overt HIV-associated dementia (HAD), and after antiretroviral treatment (ART)-induced viral suppression. HIV-negative controls were also examined.FindingsPlasma and CSF NFL concentrations were very highly correlated (r = 0.89, P < 0.0001). While NFL was more than 50-fold lower plasma than CSF it was within the quantifiable range of the new plasma assay in all subjects, including the HIV negatives and the HIV positives with normal CSF NFL concentrations. The pattern of NFL changes were almost identical in plasma and CSF, both exhibiting similar age-related increases in concentrations along with highest values in HAD and substantial elevations in ART-naïve neuroasymptomatic subjects with low blood CD4(+) T cells.InterpretationThese results show that plasma NFL may prove a valuable tool to evaluate ongoing CNS injury in HIV infection that may be applied in the clinic and in research settings to assess the presence if active CNS injury. Because CSF NFL is also elevated in a variety of other CNS disorders, sensitive measures of plasma NFL may similarly prove useful in other settings.

In this study, it is aimed to investigate the effects of central ventilation system hood design on capture performance. Commercial computational fluid dynamic (CFD) software was used to optimize the hood design and predict capture performance. Thanks to the CFD software, the hood with real dimensions was modeled and numerical analyzes were carried out. In numerical analysis, the turbulent flow in the hood was prevented by the air guide attached to the hood. In this way, an increase was achieved in the hood capture velocity and airflow rate. With the information obtained as a result of CFD analysis, hood prototypes were created and real environment experiments were carried out. Numerical analysis performed at different flow rates were confirmed by experimental analyzes. As a result, CFD analysis showed that the air guide added to the hood prevents turbulence in the air flow and increases the hood performance. [ABSTRACT FROM AUTHOR]

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