Search results for: visual and thermal comfort
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5660

Search results for: visual and thermal comfort

5420 The Effect of the Incorporation of Glass Powder into Cement Sorel

Authors: Rim Zgueb, Noureddine Yacoubi

Abstract:

The work concerns thermo-mechanical properties of cement Sorel mixed with different proportions of glass powder. Five specimens were developed. Four different glass powder mixtures were developed 5%, 10%, 15% and 20% with one control sample without glass powder. The research presented in this study focused on evaluating the effects of replacing portion of glass powder with various percentages of cement Sorel. The influence of the glass powder on the thermal conductivity, thermal diffusivity, bulk density and compressive strength of the cement Sorel at 28 days of curing were determined. The thermal property of cement was measured by using Photothermal deflection technique PTD. The results revealed that the glass powder additive affected greatly on the thermal properties of the cement.

Keywords: cement sorel, photothermal deflection technique, thermal conductivity, thermal diffusivity

Procedia PDF Downloads 383
5419 Event Related Potentials in Terms of Visual and Auditory Stimuli

Authors: Seokbeen Lim, KyeongSeok Sim, DaKyeong Shin, Gilwon Yoon

Abstract:

Event-related potential (ERP) is one of the useful tools for investigating cognitive reactions. In this study, the potential of ERP components detected after auditory and visual stimuli was examined. Subjects were asked to respond upon stimuli that were of three categories; Target, Non-Target and Standard stimuli. The ERP after stimulus was measured. In the experiment of visual evoked potentials (VEPs), the subjects were asked to gaze at a center point on the monitor screen where the stimuli were provided by the reversal pattern of the checkerboard. In consequence of the VEP experiments, we observed consistent reactions. Each peak voltage could be measured when the ensemble average was applied. Visual stimuli had smaller amplitude and a longer latency compared to that of auditory stimuli. The amplitude was the highest with Target and the smallest with Standard in both stimuli.

Keywords: auditory stimulus, EEG, event related potential, oddball task, visual stimulus

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5418 Research on Detection of Web Page Visual Salience Region Based on Eye Tracker and Spectral Residual Model

Authors: Xiaoying Guo, Xiangyun Wang, Chunhua Jia

Abstract:

Web page has been one of the most important way of knowing the world. Humans catch a lot of information from it everyday. Thus, understanding where human looks when they surfing the web pages is rather important. In normal scenes, the down-top features and top-down tasks significantly affect humans’ eye movement. In this paper, we investigated if the conventional visual salience algorithm can properly predict humans’ visual attractive region when they viewing the web pages. First, we obtained the eye movement data when the participants viewing the web pages using an eye tracker. By the analysis of eye movement data, we studied the influence of visual saliency and thinking way on eye-movement pattern. The analysis result showed that thinking way affect human’ eye-movement pattern much more than visual saliency. Second, we compared the results of web page visual salience region extracted by Itti model and Spectral Residual (SR) model. The results showed that Spectral Residual (SR) model performs superior than Itti model by comparison with the heat map from eye movements. Considering the influence of mind habit on humans’ visual region of interest, we introduced one of the most important cue in mind habit-fixation position to improved the SR model. The result showed that the improved SR model can better predict the human visual region of interest in web pages.

Keywords: web page salience region, eye-tracker, spectral residual, visual salience

Procedia PDF Downloads 246
5417 Computational Fluid Dynamics Based Analysis of Heat Exchanging Performance of Rotary Thermal Wheels

Authors: H. M. D. Prabhashana Herath, M. D. Anuradha Wickramasinghe, A. M. C. Kalpani Polgolla, R. A. C. Prasad Ranasinghe, M. Anusha Wijewardane

Abstract:

The demand for thermal comfort in buildings in hot and humid climates increases progressively. In general, buildings in hot and humid climates spend more than 60% of the total energy cost for the functionality of the air conditioning (AC) system. Hence, it is required to install energy efficient AC systems or integrate energy recovery systems for both new and/or existing AC systems whenever possible, to reduce the energy consumption by the AC system. Integrate a Rotary Thermal Wheel as the energy recovery device of an existing AC system has shown very promising with attractive payback periods of less than 5 years. A rotary thermal wheel can be located in the Air Handling Unit (AHU) of a central AC system to recover the energy available in the return air stream. During this study, a sensitivity analysis was performed using a CFD (Computational Fluid Dynamics) software to determine the optimum design parameters (i.e., rotary speed and parameters of the matrix profile) of a rotary thermal wheel for hot and humid climates. The simulations were performed for a sinusoidal matrix geometry. Variation of sinusoidal matrix parameters, i.e., span length and height, were also analyzed to understand the heat exchanging performance and the induced pressure drop due to the air flow. The results show that the heat exchanging performance increases when increasing the wheel rpm. However, the performance increment rate decreases when increasing the rpm. As a result, it is more advisable to operate the wheel at 10-20 rpm. For the geometry, it was found that the sinusoidal geometries with lesser spans and higher heights have higher heat exchanging capabilities. Considering the sinusoidal profiles analyzed during the study, the geometry with 4mm height and 3mm width shows better performance than the other combinations.

Keywords: air conditioning, computational fluid dynamics, CFD, energy recovery, heat exchangers

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5416 The Relation between Learning Styles and English Achievement in the Language Training Centre

Authors: Nurul Yusnita

Abstract:

Many studies have been developed to help the students to get good achievement in English learning. They can be from the teaching method or psychological ones. One of the psychological studies in educational research is learning style. In some ways, learning style can affect the achievement of the students. This study aimed to examine 4 (four) learning styles and their relations to English achievement among the students learning English in Language Training Center of Universitas Muhammadiyah Yogyakarta (LTC UMY). The method of this study was descriptive analytical. The sample consisted of 39 Accounting students in LTC UMY. The data was collected through questionnaires with Likert-scale. The achievement was obtained from the grade of the students. To analyze the questionnaires and to see the relation between the learning styles and the student achievement, SPSS statistical software of correlational analysis was used. The result showed that both visual and auditory had the same percentage of 35.9% (14 students). 3 students (7.7%) had kinaesthetic learning style and 8 students (20.5%) had visual and auditory ones. Meanwhile, there were 5 students (12.8%) who had visual learning style could increase their grades. Only 1 student (2.5%) who had visual and auditory could improve his grade. Besides grade increase, there were also grade decrease. Students with visual, auditory, visual and auditory, and kinaesthetic learning styles were 3 students (7.7%), 5 students (12%), 4 students (10.2%) and 1 student (2.5%) respectively. In conclusion, there was no significant relationship between learning style and English achievement. Most of the good achievers were the students with visual and auditory learning styles and most of them preferred visual method. The implication is the teachers and material designers could improve their method through visual things to achieve effective English teaching learning.

Keywords: accounting students, English achievement, language training centre, learning styles

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5415 Peripheral Neuropathy after Locoregional Anesthesia

Authors: Dalila Chaid, Bennameur Fedilli, Mohammed Amine Bellelou

Abstract:

The study focuses on the experience of lower-limb amputees, who face both physical and psychological challenges due to their disability. Chronic neuropathic pain and various types of limb pain are common in these patients. They often require orthopaedic interventions for issues such as dressings, infection, ulceration, and bone-related problems. Research Aim: The aim of this study is to determine the most suitable anaesthetic technique for lower-limb amputees, which can provide them with the greatest comfort and prolonged analgesia. The study also aims to demonstrate the effectiveness and cost-effectiveness of ultrasound-guided local regional anaesthesia (LRA) in this patient population. Methodology: The study is an observational analytical study conducted over a period of eight years, from 2010 to 2018. It includes a total of 955 cases of revisions performed on lower limb stumps. The parameters analyzed in this study include the effectiveness of the block and the use of sedation, the duration of the block, the post-operative visual analog scale (VAS) scores, and patient comfort. Findings: The study findings highlight the benefits of ultrasound-guided LRA in providing comfort by optimizing post-operative analgesia, which can contribute to psychological and bodily repair in lower-limb amputees. Additionally, the study emphasizes the use of alpha2 agonist adjuvants with sedative and analgesic properties, long-acting local anaesthetics, and larger volumes for better outcomes. Theoretical Importance: This study contributes to the existing knowledge by emphasizing the importance of choosing an appropriate anaesthetic technique for lower-limb amputees. It highlights the potential of ultrasound-guided LRA and the use of specific adjuvants and local anaesthetics in improving post-operative analgesia and overall patient outcomes. Data Collection and Analysis Procedures: Data for this study were collected through the analysis of medical records and relevant documentation related to the 955 cases included in the study. The effectiveness of the anaesthetic technique, duration of the block, post-operative pain scores, and patient comfort were analyzed using statistical methods. Question Addressed: The study addresses the question of which anaesthetic technique would be most suitable for lower-limb amputees to provide them with optimal comfort and prolonged analgesia. Conclusion: The study concludes that ultrasound-guided LRA, along with the use of alpha2 agonist adjuvants, long-acting local anaesthetics, and larger volumes, can be an effective approach in providing comfort and improving post-operative analgesia for lower-limb amputees. This technique can potentially contribute to the psychological and bodily repair of these patients. The findings of this study have implications for clinical practice in the management of lower-limb amputees, highlighting the importance of personalized anaesthetic approaches for better outcomes.

Keywords: neuropathic pain, ultrasound-guided peripheral nerve block, DN4 quiz, EMG

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5414 Crystallized Colored Towels Obtained by Special Coloration of Yarns

Authors: Hasan Eskin, Gizem Özmen, A. Nazmi Çeler

Abstract:

When we examine the home textile development process, it follows a parallel line with the other textile products especially in the garment fabrics in terms of raw materials, production technologies and pattern characteristics. As a result, the expectations of people regarding textile, comfort, pattern (texture) and color properties are increasing. One of the places where comfort is most sought after is bath, pool, sea and baths. In addition to the material and technique that make up the physical structure in woven fabrics, color has an impressive importance with its strong effects. Color is the most prominent element in the fabric, and the color and texture are visually reinforcing. Evaluation of color in fabric is a personal phenomenon. Factors that determine color determination in fabric are the amount of color used, color ratio and its relationship with other colors. In this project; Considering the effect of color dimensions on human, we are talking about the crystallized colored towel that we developed in terms of comfort and texture properties. The basis of the effect created in the towel; It is formed by bending the yarn from its own special blend and the harmonious appearance of the natural crystallized rainbow colors with the pattern effect it determines on the warp yarns by using the weft yarns in the weaving. In addition, by using different weaving techniques and colors, alternatives can be created and personalized patterns can be created. One side of the towel determines the properties related to color, while the pile part determines the comfort characteristics with its soft touch and water absorbency.

Keywords: color effect, comfort, towel, weaving technique

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5413 Thermal, Chemical, and Mineralogical Properties of Soil Building Blocks Reinforced with Cement

Authors: Abdelmalek Ammari

Abstract:

This paper represents an experimental study to determine the effect between thermal conductivity of Compressed Earth Block Stabilized (CEBs) by cement and the mineralogical and chemical analyses of soil, all the samples of CEB in the dry state and with different content of cement, the samples made by soil stabilized by Portland Cement. The soil used collected from fez city in Morocco. That determination of the thermal conductivity of CEBs plays an important role when considering its suitability for energy saving insulation. The measurement technique used to determine thermal conductivity is called hot ring method, the thermal conductivity of the tested samples is strongly affected by the quantity of the cement added. The soil of Fez, mainly composed of calcite, quartz, and dolomite, improved the behaviour of the material by the addition of cement. The findings suggest that to manufacture lightweight samples with high thermal insulation properties, it is advisable to use clays that contain quartz. . In addition, quartz has high thermal conductivity.

Keywords: compressed earth blocks, thermal conductivity, mineralogical, chemical, temperature

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5412 Thermal Diffusion of Photovoltaic Organic Semiconductors Determined by Scanning Photothermal Deflection Technique

Authors: K.L. Chiu, Johnny K. W. Ho, M. H. Chan, S. H. Cheung, K. H. Chan, S.K. So

Abstract:

Thermal diffusivity is an important quantity in heat conduction. It measures the rate of heat transfer from the hot side to the cold side of a material. In solid-state materials, thermal diffusivity reveals information related to morphologies and solid quality, as thermal diffusivity can be affected by microstructures. However, thermal diffusivity studies on organic semiconductors are very limited. In this study, scanning photothermal deflection (SPD) technique is used to study the thermal diffusivities of different classes of semiconducting polymers. The reliability of the technique was confirmed by crossing-checking our SPD derived experimental values of different reference materials with their known diffusivities from the literature. To show that thermal diffusivity determination is a potential tool for revealing microscopic properties of organic photovoltaic semiconductors, SPD measurements were applied to various organic semiconducting films with different crystallinities. It is observed that organic photovoltaic semiconductors possess low thermal diffusivity, with values in the range of 0.3mm²/s to 1mm²/s. It is also discovered that polymeric photovoltaic semiconductors with greater molecular planarity, stronger stacking and higher crystallinity would possess greater thermal diffusivities. Correlations between thermal, charge transport properties will be discussed.

Keywords: polymer crystallinity, photovoltaic organic semiconductors, photothermal deflection technique, thermal diffusion

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5411 Visual Thinking Routines: A Mixed Methods Approach Applied to Student Teachers at the American University in Dubai

Authors: Alain Gholam

Abstract:

Visual thinking routines are principles based on several theories, approaches, and strategies. Such routines promote thinking skills, call for collaboration and sharing of ideas, and above all, make thinking and learning visible. Visual thinking routines were implemented in the teaching methodology graduate course at the American University in Dubai. The study used mixed methods. It was guided by the following two research questions: 1). To what extent do visual thinking inspire learning in the classroom, and make time for students’ questions, contributions, and thinking? 2). How do visual thinking routines inspire learning in the classroom and make time for students’ questions, contributions, and thinking? Eight student teachers enrolled in the teaching methodology course at the American University in Dubai (Spring 2017) participated in the following study. First, they completed a survey that measured to what degree they believed visual thinking routines inspired learning in the classroom and made time for students’ questions, contributions, and thinking. In order to build on the results from the quantitative phase, the student teachers were next involved in a qualitative data collection phase, where they had to answer the question: How do visual thinking routines inspire learning in the classroom and make time for students’ questions, contributions, and thinking? Results revealed that the implementation of visual thinking routines in the classroom strongly inspire learning in the classroom and make time for students’ questions, contributions, and thinking. In addition, student teachers explained how visual thinking routines allow for organization, variety, thinking, and documentation. As with all original, new, and unique resources, visual thinking routines are not free of challenges. To make the most of this useful and valued resource, educators, need to comprehend, model and spread an awareness of the effective ways of using such routines in the classroom. It is crucial that such routines become part of the curriculum to allow for and document students’ questions, contributions, and thinking.

Keywords: classroom display, student engagement, thinking classroom, visual thinking routines

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5410 The Influence of Fiber Volume Fraction on Thermal Conductivity of Pultruded Profile

Authors: V. Lukášová, P. Peukert, V. Votrubec

Abstract:

Thermal conductivity in the x, y and z-directions was measured on a pultruded profile that was manufactured by the technology of pulling from glass fibers and a polyester matrix. The results of measurements of thermal conductivity showed considerable variability in different directions. The caused variability in thermal conductivity was expected due fraction variations. The cross-section of the pultruded profile was scanned. An image analysis illustrated an uneven distribution of the fibers and the matrix in the cross-section. The distribution of these inequalities was processed into a Voronoi diagram in the observed area of the pultruded profile cross-section. In order to verify whether the variation of the fiber volume fraction in the pultruded profile can affect its thermal conductivity, the numerical simulations in the ANSYS Fluent were performed. The simulation was based on the geometry reconstructed from image analysis. The aim is to quantify thermal conductivity numerically. Above all, images with different volume fractions were chosen. The results of the measured thermal conductivity were compared with the calculated thermal conductivity. The evaluated data proved a strong correlation between volume fraction and thermal conductivity of the pultruded profile. Based on presented results, a modification of production technology may be proposed.

Keywords: pultrusion profile, volume fraction, thermal conductivity, numerical simulation

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5409 Contemplation of Thermal Characteristics by Filling Ratio of Aluminium Oxide Nano Fluid in Wire Mesh Heat Pipe

Authors: D. Mala, S. Sendhilnathan, D. Ratchagaraja

Abstract:

In this paper, the performance of heat pipe in terms of overall heat transfer coefficient and thermal resistance is quantified by varying the volume of working fluid and the performance parameters are contemplated. For this purpose Al2O3 nano particles with a density of 9.8 gm/cm3 and a volume concentration of 1% is used as the working fluid in experimental heat pipe. The performance of heat pipe was evaluated by conducting experiments with different thermal loads and different angle of inclinations. Thermocouples are used to record the temperature distribution across the experiment. The results provide evidence that the suspension of Al2O3 nano particles in the base fluid increases the thermal efficiency of heat pipe and can be used in practical heat exchange applications.

Keywords: heat pipe, angle of inclination, thermal resistance, thermal efficiency

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5408 Evaluation of Thermal Barrier Coating Applied to the Gas Turbine Blade According to the Thermal Gradient

Authors: Jeong-Min Lee, Hyunwoo Song, Yonseok Kim, Junghan Yun, Jungin Byun, Jae-Mean Koo, Chang-Sung Seok

Abstract:

The Thermal Barrier Coating (TBC) prevents heat directly transferring from the high-temperature flame to the substrate. Top coat and bond coat compose the TBC and top coat consists of a ceramic and bond coat increases adhesion between the top coat and the substrate. The TBC technology drops the substrate surface temperature by about 150~200°C. In addition, the TBC system has a cooling system to lower the blade temperature by the air flow inside the blade. Then, as a result, the thermal gradient occurs inside the blade by cooling. Also, the internal stress occurs due to the difference in thermal expansion. In this paper, the finite element analyses (FEA) were performed and stress changes were derived according to the thermal gradient of the TBC system. The stress was increased due to the cooling, but difference of the stress between the top coat and bond coat was decreased. So, delamination in the interface between top coat and bond coat.

Keywords: gas turbine blade, Thermal Barrier Coating (TBC), thermal gradient, Finite Element Analysis (FEA)

Procedia PDF Downloads 579
5407 Study of Heat Transfer through the Ground and its Accumulation Properties to Increase the Energy Efficiency of Underground Buildings

Authors: Sandeep Bandarwadkar, Tadas Zdankus

Abstract:

To maintain a comfortable indoor temperature for its residents in the colder season, heating a building is necessary. Due to the expansion in the construction sectors, the consumption of heating energy is increasing. According to Eurostat data, in the European Union, the share of energy consumption of heating energy for space and cooling in residential buildings was around 63% in 2019. These figures indicate that heating energy still accounts for a significant portion of total energy consumption in Europe. Innovation is crucial to reduce energy consumption in buildings and achieve greater energy efficiency and sustainability. It can bring about new solutions that are smarter and more natural energy generation to reduce greenhouse gas emissions. The ground can serve as an effective and sustainable heat accumulator for heating and cooling. The temperature of the ground is higher than that of the ambient air in the colder period and lower in the warmer period. The building deep in the soil could use less thermal energy compared to the above-ground buildings that provide the same amount of thermal comfort. The temperature difference between the soil and the air inside the building decreases as the temperature of the soil increases. In progress, this process generates the condition that acts against heat loss. However, heat dissipates further to the consecutive layers and reaches thermal equilibrium. The charging of the ground by heat and its dissipation through the adjacent soil layers was investigated experimentally. The results of this research showed that 9% of the energy savings in partially underground buildings and 44.4% in completely underground buildings were derived from heating the space. Heat loss to the ground is treated as a charge of the soil by thermal energy. The dependence of the intensity of the charge on time was analysed and presented.

Keywords: heat transfer, accumulation of heat, underground building, soil charge

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5406 Thermal Property Improvement of Silica Reinforced Epoxy Composite Specimens

Authors: Hyu Sang Jo, Gyo Woo Lee

Abstract:

In this study, the mechanical and thermal properties of epoxy composites that are reinforced with micrometer-sized silica particles were investigated by using the specimen experiments. For all specimens used in this study (from the baseline to specimen containing 70 wt% silica filler), the tensile strengths were gradually increased by 8-10%, but the ductility of the specimen was decreased by 34%, compared with those of the baseline samples. Similarly, for the samples containing 70 wt% silica filler, the coefficient of thermal expansion was reduced by 25%, but the thermal conductivity was increased by 100%, compared with those of the baseline samples. The improvement of thermal stability of the silica-reinforced specimen was confirmed to be within the experimented range, and the smaller silica particle was found to be more effective in delaying the thermal expansion of the specimens. When the smaller particle was used as filler, due to the increased specific interface area between filler and matrix, the thermal conductivities of the composite specimens were measured to be slightly lower than those of the specimens reinforced with the larger particle.

Keywords: carbon nanotube filler, epoxy composite, mechanical property, thermal property

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5405 Efficiency Validation of Hybrid Geothermal and Radiant Cooling System Implementation in Hot and Humid Climate Houses of Saudi Arabia

Authors: Jamil Hijazi, Stirling Howieson

Abstract:

Over one-quarter of the Kingdom of Saudi Arabia’s total oil production (2.8 million barrels a day) is used for electricity generation. The built environment is estimated to consume 77% of the total energy production. Of this amount, air conditioning systems consume about 80%. Apart from considerations surrounding global warming and CO2 production it has to be recognised that oil is a finite resource and the KSA like many other oil rich countries will have to start to consider a horizon where hydro-carbons are not the dominant energy resource. The employment of hybrid ground cooling pipes in combination with black body solar collection and radiant night cooling systems may have the potential to displace a significant proportion of oil currently used to run conventional air conditioning plant. This paper presents an investigation into the viability of such hybrid systems with the specific aim of reducing carbon emissions while providing all year round thermal comfort in a typical Saudi Arabian urban housing block. At the outset air and soil temperatures were measured in the city of Jeddah. A parametric study then was carried out by computational simulation software (Design Builder) that utilised the field measurements and predicted the cooling energy consumption of both a base case and an ideal scenario (typical block retro-fitted with insulation, solar shading, ground pipes integrated with hypocaust floor slabs/ stack ventilation and radiant cooling pipes embed in floor).Initial simulation results suggest that careful ‘ecological design’ combined with hybrid radiant and ground pipe cooling techniques can displace air conditioning systems, producing significant cost and carbon savings (both capital and running) without appreciable deprivation of amenity.

Keywords: energy efficiency, ground pipe, hybrid cooling, radiative cooling, thermal comfort

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5404 Investigation of the Functional Impact of Amblyopia on Visual Skills in Children

Authors: Chinmay V. Deshpande

Abstract:

Purpose: To assess the efficiency of visual functions and visual skills in strabismic & anisometropic amblyopes and to assess visual acuity and contrast sensitivity in anisometropic amblyopes with spectacles & contact lenses. Method: In a prospective clinical study, 32 children ageing from 5 to 15 years presenting with amblyopia in a pediatric department of Shri Ganapati Netralaya Jalna, India, were assessed for a period of three & half months. Visual acuity was measured with Snellen’s and Bailey-Lovie log MAR charts whereas contrast sensitivity was measured with Pelli-Robson chart with spectacles and contact lenses. Saccadic movements were assessed with SCCO scoring criteria and accommodative facility was checked with ±1.50 DS flippers. Stereopsis was assessed with TNO test. Results: By using Wilcoxon sign rank test p-value < 0.05 (< 0.001), the mean linear visual acuity was 0.29 (≈ 6/21) and mean single optotype visual acuity found to be 0.36 (≈ 6/18). Mean visual acuity of 0.27(≈ 6/21) with spectacles improved to 0.33 (≈ 6/18) with contact lenses in amblyopic eyes. The mean Log MAR visual acuity with spectacles and contact lens were found to be 0.602( ≈6/24) and 0.531(≈ 6/21) respectively. The contrast threshold out of 20 amblyopic eyes shows that mean contrast threshold changed in 9 patients from spectacles 0.27 to contact lens 0.19 respectively. The mean accommodative facility assessed was 5.31(± 2.37). 24 subjects (75%) revealed marked saccadic defects on the test applied. 78% subjects didn’t show even gross stereoscopic ability on TNO test. Conclusion: This study supports the facts about amblyopia and associated deficits in visual skills which are claimed in previous studies. In addition, anisometropic amblyopia can be managed better with contact lenses.

Keywords: strabismus, anisometropia, amblyopia, contrast sensitivity, saccades, stereopsis

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5403 Preserved Relative Differences between Regions of Different Thermal Scans

Authors: Tahir Majeed, Michael Handschuh, René Meier

Abstract:

Rheumatoid arthritis patients have swelling and pain at the joints of the hand. The regions where the patient feels pain also show increased body temperature. Thermal cameras can be used to detect the rise in temperature of the affected regions. To monitor the disease progression of rheumatoid arthritis patients, they must visit the clinic regularly for scanning and examination. After scanning and evaluation, the dosage of the medicine is regulated accordingly. To monitor the disease progression over time, the correlation between the images between different visits must be established. It has been observed that by using low-cost thermal cameras, the thermal measurements do not remain the same over time, even within a single scanning. In some situations, temperatures can vary as much as 2°C within the same scanning sequence. In this paper, it has been shown that although the absolute temperature varies over time, the relative difference between the different regions remains similar. Results have been computed over four scanning sequences and are presented.

Keywords: relative thermal difference, rheumatoid arthritis, thermal imaging, thermal sensors

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5402 Cyclic Heating Effect on Hardness of Copper

Authors: Tahany W. Sadak

Abstract:

Presented work discusses research results concerning the effect of the heat treatment process. Thermal fatigue which expresses repeated heating and cooling processes affect the ductility or the brittleness of the material. In this research, 70 specimens of copper (1.5 mm thickness, 85 mm length, 32 mm width) are subjected to thermal fatigue at different conditions. Heating temperatures Th are 100, 300 and 500 °C. Number of repeated cycles N is from 1 to 100. Heating time th =600 Sec, and Cooling time; tC= 900 Sec.  Results are evaluated and then compared to each other and to that of specimens without subjected to thermal fatigue.

Keywords: copper, thermal analysis, heat treatment, hardness, thermal fatigue

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5401 Exploring the Aesthetics of Sexual Violence in Therese Park’s ‘A Gift of the Emperor’: A Brief Study on Korean Comfort Women

Authors: Khushboo Verma

Abstract:

The use of rape as a weapon of war has been in existence for as early as the middle ages. Women, during the conflict, have been treated as the spoils of war, a reward for the conquering soldiers granted to them by their superiors which is, arguably, most often overlooked as part of the collateral damage that is unavoidable in conflict zones. Korean-born Therese Park’s first novel, A Gift of the Emperor (1997), describes one such atrocious incidence wherein she highlights the active role the Japanese military played in procuring and condoning trafficking of women, who were euphemistically referred to as ‘comfort women’, for prostitution during World War II. This paper thus aims to look at the remembering and reckonings of these women, which fueled a range of creative gestures in the artistic representations and knowledge production by Korean American artists and writers. The essay divides into three parts wherein first it tries to highlight the relationship of the state and the self in relation to the ‘comfort women’ as to who bears the onus of the exploitation of these women, or the responsibility for the redressal with the present-day notions of human rights as studied through Ueno Chizuko’s ‘The Politics of Memory: Nation, Individual and Self’ (1999). There are several narratological elements of the text that are of interest here which shall be viewed and analysed throughout the paper as well. The second part of the paper talks about the aesthetics of rape and sexual violence as represented or (mis)represented by Park in her novel as she attempts to give voice to the victim and retain her and her suffering as the central focus of the narrative. Finally, the third part of the novel explores as well as places the novel in the context of debates over the highly contested issue of ‘comfort women’ and the actual ‘comfort women’ survivors’ testimonies. For this purpose, the present study focuses on Dori Laub’s ‘Truth and Testimony: The Process and the Struggle’ (1991).

Keywords: Korean comfort women, survivors’ testimonies, sexual slavery, aesthetics of sexual violence, horrible memories

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5400 An Analysis of the Temporal Aspects of Visual Attention Processing Using Rapid Series Visual Processing (RSVP) Data

Authors: Shreya Borthakur, Aastha Vartak

Abstract:

This Electroencephalogram (EEG) project on Rapid Visual Serial Processing (RSVP) paradigm explores the temporal dynamics of visual attention processing in response to rapidly presented visual stimuli. The study builds upon previous research that used real-world images in RSVP tasks to understand the emergence of object representations in the human brain. The objectives of the research include investigating the differences in accuracy and reaction times between 5 Hz and 20 Hz presentation rates, as well as examining the prominent brain waves, particularly alpha and beta waves, associated with the attention task. The pre-processing and data analysis involves filtering EEG data, creating epochs for target stimuli, and conducting statistical tests using MATLAB, EEGLAB, Chronux toolboxes, and R. The results support the hypotheses, revealing higher accuracy at a slower presentation rate, faster reaction times for less complex targets, and the involvement of alpha and beta waves in attention and cognitive processing. This research sheds light on how short-term memory and cognitive control affect visual processing and could have practical implications in fields like education.

Keywords: RSVP, attention, visual processing, attentional blink, EEG

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5399 Thermal Conductivity and Optical Absorption of GaInAsSb/GaSb Laser Structure: Impact of Annealing Time

Authors: Soufiene Ilahi, Noureddine Yacoubi

Abstract:

GaInAsSb grown on GaSb substrate is an interesting material employed as an active layer in vertical-cavity surface-emitting lasers (VCSELs) operating in mid-infrared emission. This material presents some advantages like highs optical absorption coefficient and good thermal conductivity, which is very desirable for VCSEL application. In this paper, we have investigated the effects of thermal annealing on optical properties and thermal conductivity of GaInAsSb/GaSb. The studies are carried out by means of the photo thermal deflection spectroscopy technique (PDS). In fact, optical absorption spectrum and thermal conductivity have been determined by a comparison between the experimental and theoretical phases of the PDS signal. We have found that thermal conductivity increased significantly to 13 W/m.K for GaInAsSb annealed during 60 min. In addition, we have found that bandgap energy is blue-shifted around 30 meV. The amplitudes signal of PDS reveals multiple reflections as a function of annealing time, which reflect the high crystalline quality of the layer.

Keywords: thermal conductivity, bandgap energy of GaInAsSb, GaInAsSb active layer, optical absorption

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5398 Comparison of the Thermal Characteristics of Induction Motor, Switched Reluctance Motor and Inset Permanent Magnet Motor for Electric Vehicle Application

Authors: Sadeep Sasidharan, T. B. Isha

Abstract:

Modern day electric vehicles require compact high torque/power density motors for electric propulsion. This necessitates proper thermal management of the electric motors. The main focus of this paper is to compare the steady state thermal analysis of a conventional 20 kW 8/6 Switched Reluctance Motor (SRM) with that of an Induction Motor and Inset Permanent Magnet (IPM) motor of the same rating. The goal is to develop a proper thermal model of the three types of models for Finite Element Thermal Analysis. JMAG software is used for the development and simulation of the thermal models. The results show that the induction motor is subjected to more heating when used for electric vehicle application constantly, compared to the SRM and IPM.

Keywords: electric vehicles, induction motor, inset permanent magnet motor, loss models, switched reluctance motor, thermal analysis

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5397 Pictorial Multimodal Analysis of Selected Paintings of Salvador Dali

Authors: Shaza Melies, Abeer Refky, Nihad Mansoor

Abstract:

Multimodality involves the communication between verbal and visual components in various discourses. A painting represents a form of communication between the artist and the viewer in terms of colors, shades, objects, and the title. This paper aims to present how multimodality can be used to decode the verbal and visual dimensions a painting holds. For that purpose, this study uses Kress and van Leeuwen’s theoretical framework of visual grammar for the analysis of the multimodal semiotic resources of selected paintings of Salvador Dali. This study investigates the visual decoding of the selected paintings of Salvador Dali and analyzing their social and political meanings using Kress and van Leeuwen’s framework of visual grammar. The paper attempts to answer the following questions: 1. How far can multimodality decode the verbal and non-verbal meanings of surrealistic art? 2. How can Kress and van Leeuwen’s theoretical framework of visual grammar be applied to analyze Dali’s paintings? 3. To what extent is Kress and van Leeuwen’s theoretical framework of visual grammar apt to deliver political and social messages of Dali? The paper reached the following findings: the framework’s descriptive tools (representational, interactive, and compositional meanings) can be used to analyze the paintings’ title and their visual elements. Social and political messages were delivered by appropriate usage of color, gesture, vectors, modality, and the way social actors were represented.

Keywords: multimodal analysis, painting analysis, Salvador Dali, visual grammar

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5396 Thermal and Flammability Properties of Paraffin/Nanoclay Composite Phase Change Materials Incorporated in Building Materials for Thermal Energy Storage

Authors: Awni H. Alkhazaleh, Baljinder K. Kandola

Abstract:

In this study, a form-stable composite Paraffin/Nanoclay (PA-NC) has been prepared by absorbing PA into porous particles of NC to be used for low-temperature latent heat thermal energy storage. The leakage test shows that the maximum mass fraction of PA that can be incorporated in NC without leakage is 60 wt.%. Differential scanning calorimetry (DSC) has been used to measure the thermal properties of the PA and PA-NC both before and after incorporation in plasterboard (PL). The mechanical performance of the samples has been evaluated in flexural mode. The thermal energy storage performance has been studied using a small test chamber (100 mm × 100 mm × 100 mm) made from 10 mm thick PL and measuring the temperatures using thermocouples. The flammability of the PL+PL-NC has been discussed using a cone calorimeter. The results indicate that the form composite PA has good potential for use as thermal energy storage materials in building applications.

Keywords: building materials, flammability, phase change materials, thermal energy storage

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5395 Amine Hardeners with Carbon Nanotubes Dispersing Ability for Epoxy Coating Systems

Authors: Szymon Kugler, Krzysztof Kowalczyk, Tadeusz Spychaj

Abstract:

An addition of carbon nanotubes (CNT) can simultaneously improve many features of epoxy coatings, i.e. electrical, mechanical, functional and thermal. Unfortunately, this nanofiller negatively affects visual properties of the coatings, such as transparency and gloss. The main reason for the low visual performance of CNT-modified epoxy coatings is the lack of compatibility between CNT and popular amine curing agents, although epoxy resins based on bisphenol A are indisputable good CNT dispersants. This is a serious obstacle in utilization of the coatings in advanced applications, demanding both high transparency and electrical conductivity. The aim of performed investigations was to find amine curing agents exhibiting affinity for CNT, and ensuring good performance of epoxy coatings with them. Commercially available CNT was dispersed in epoxy resin, as well as in different aliphatic, cycloaliphatic and aromatic amines, using one of two dispergation methods: ultrasonic or mechanical. The CNT dispersions were subsequently used in the preparation of epoxy coating compositions and coatings on a transparent substrate. It was found that amine derivative of bio-based cardanol, as well as modified o-tolylbiguanide exhibit significant CNT, dispersing properties, resulting in improved transparent/electroconductive performance of epoxy coatings. In one of prepared coating systems just 0.025 wt.% (250 ppm) of CNT was enough to obtain coatings with semi conductive properties, 83% of transparency as well as perfect chemical resistance to methyl-ethyl ketone and improved thermal stability. Additionally, a theory of the influence of amine chemical structure on CNT dispersing properties was proposed.

Keywords: bio-based cardanol, carbon nanotubes, epoxy coatings, tolylbiguanide

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5394 Comparing the Experimental Thermal Conductivity Results Using Transient Methods

Authors: Sofia Mylona, Dale Hume

Abstract:

The main scope of this work is to compare the experimental thermal conductivity results of fluids between devices using transient techniques. A range of different liquids within a range of viscosities was measured with two or more devices, and the results were compared between the different methods and the reference equations wherever it was available. The liquids selected are the most commonly used in academic or industrial laboratories to calibrate their thermal conductivity instruments having a variety of thermal conductivity, viscosity, and density. Three transient methods (Transient Hot Wire, Transient Plane Source, and Transient Line Source) were compared for the thermal conductivity measurements taken by using them. These methods have been chosen as the most accurate and because they all follow the same idea; as a function of the logarithm of time, the thermal conductivity is calculated from the slope of a plot of sensor temperature rise. For all measurements, the selected temperature range was at the atmospheric level from 10 to 40 ° C. Our results are coming with an agreement with the objections of several scientists over the reliability of the results of a few popular devices. The observation was surprising that the device used in many laboratories for fast measurements of liquid thermal conductivity display deviations of 500 percent which can be very poorly reproduced.

Keywords: accurate data, liquids, thermal conductivity, transient methods.

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5393 Evaluation of Soil Thermal-Entropy Properties with a Single-Probe Heat-Pulse Technique

Authors: Abdull Halim Abdull, Nasiman Sapari, Mohammad Haikal Asyraf Bin Anuar

Abstract:

Although soil thermal properties are required in many areas to improve oil recovery, they are seldom measured on a routine basis. Reasons for this are unclear, but may be related to a lack of suitable instrumentation and entropy theory. We integrate single probe thermal gradient for the radial conduction of a short-duration heat pulse away from a single electrode source, and compared it with the theory for an instantaneously heated line source. By measuring the temperature response at a short distance from the line source, and applying short-duration heat-pulse theory, we can extract all the entropy properties, the thermal diffusivity, heat capacity, and conductivity, from a single heat-pulse measurement. Results of initial experiments carried out on air-dry sand and clay materials indicate that this heat-pulse method yields soil thermal properties that compare well with thermal properties measured by single electrode.

Keywords: entropy, single probe thermal gradient, soil thermal, probe heat

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5392 Tourism Climate Index Environmental Assessment of Piranshahr

Authors: Parvaneh Ziviar Pardehei, Esmaeil Hossinnejad

Abstract:

In this research, the tourism climate index Miczcofski (TCI) and to assess climate Trjvng Piranshahr city tourism is discussed. The index is a systematic way to evaluate the climatic conditions for tourism. To calculate the parameters of mean monthly maximum temperature, minimum relative humidity, average daily relative humidity, rainfall, sunshine and the wind speed are used. In the months of April, July, August and September of comfort there in December, January, February and March, the nerve is cold comfort factor. Baker calculation method showed that during spring and summer cooling environment, mild, pleasant, and comfortable Byvklymay there. TCI results suggest that the months of April to July are top rated and best climatic conditions in terms of comfort to the tourists. In general, indices used in this paper show that the months of April to October is the best time for tourism in the city Piranshahr.

Keywords: tourism, climate, Piranshahr city, TCI indicators and trjvng

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5391 The Intersection of Art and Technology: Innovations in Visual Communication Design

Authors: Sareh Enjavi

Abstract:

In recent years, the field of visual communication design has seen a significant shift in the way that art is created and consumed, with the advent of new technologies like virtual reality, augmented reality, and artificial intelligence. This paper explores the ways in which technology is changing the landscape of visual communication design, and how designers are incorporating new technological tools into their artistic practices. The primary objective of this research paper is to investigate the ways in which technology is influencing the creative process of designers and artists in the field of visual communication design. The paper also aims to examine the challenges and limitations that arise from the intersection of art and technology in visual communication design, and to identify strategies for overcoming these challenges. Drawing on examples from a range of fields, including advertising, fine art, and digital media, this paper highlights the exciting innovations that are emerging as artists and designers use technology to push the boundaries of traditional artistic expression. The paper argues that embracing technological innovation is essential for the continued evolution of visual communication design. By exploring the intersection of art and technology, designers can create new and exciting visual experiences that engage and inspire audiences in new ways. The research also contributes to the theoretical and methodological understanding of the intersection of art and technology, a topic that has gained significant attention in recent years. Ultimately, this paper emphasizes the importance of embracing innovation and experimentation in the field of visual communication design, and highlights the exciting innovations that are emerging as a result of the intersection of art and technology, and emphasizes the importance of embracing innovation and experimentation in the field of visual communication design.

Keywords: visual communication design, art and technology, virtual reality, interactive art, creative process

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