Search results for: Hong Zhang
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1603

Search results for: Hong Zhang

193 Inertia Friction Pull Plug Welding, a New Weld Repair Technique of Aluminium Friction Stir Welding

Authors: Guoqing Wang, Yanhua Zhao, Lina Zhang, Jingbin Bai, Ruican Zhu

Abstract:

Friction stir welding with bobbin tool is a simple technique compared to conventional FSW since the backing fixture is no longer needed and assembling labor is reduced. It gets adopted more and more in the aerospace industry as a result. However, a post-weld problem, the left keyhole, has to be fixed by forced repair welding. To close the keyhole, the conventional fusion repair could be an option if the joint properties are not deteriorated; friction push plug welding, a forced repair, could be another except that a rigid support unit is demanded at the back of the weldment. Therefore, neither of the above ways is satisfaction in welding a large enclosed structure, like rocket propellant tank. Although friction pulls plug welding does not need a backing plate, the wide applications are still held back because of the disadvantages in respects of unappropriated tensile stress, (i.e. excessive stress causing neck shrinkage of plug that will bring about back defects while insufficient stress causing lack of heat input that will bring about face defects), complicated welding parameters (including rotation speed, transverse speed, friction force, welding pressure and upset),short welding time (approx. 0.5 sec.), narrow windows and poor stability of process. In this research, an updated technique called inertia friction pull plug welding, and its equipment was developed. The influencing rules of technological parameters on joint properties of inertia friction pull plug welding were observed. The microstructure characteristics were analyzed. Based on the elementary performance data acquired, the conclusion is made that the uniform energy provided by an inertia flywheel will be a guarantee to a stable welding process. Meanwhile, due to the abandon of backing plate, the inertia friction pull plug welding is considered as a promising technique in repairing keyhole of bobbin tool FSW and point type defects of aluminium base material.

Keywords: defect repairing, equipment, inertia friction pull plug welding, technological parameters

Procedia PDF Downloads 313
192 Change of Bone Density with Treatments of Intravenous Zoledronic Acid in Patients with Osteoporotic Distal Radial Fractures

Authors: Hong Je Kang, Young Chae Choi, Jin Sung Park, Isac Kim

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Purpose: Osteoporotic fractures are an important among postmenopausal women. When osteoporotic distal radial fractures occur, osteoporosis must be treated to prevent the hip and spine fractures. Intravenous injection of Zoledronic acid is expected to improve preventing osteoporotic fractures. Many articles reported the effect of intravenous Zoledronic acid to BMD of the hip and spine fracture or non-fracture patients with low BMD. However, that with distal radial fractures has rarely been reported. Therefore, the authors decided to study the effect of Zoledronic acid in BMD score, bone union, and bone turnover markers in the patients who underwent volar plating due to osteoporotic distal radial fractures. Materials: From April 2018 to May 2022, postmenopausal women aged 55 years or older who had osteoporotic distal radial fractures and who underwent surgical treatment using volar plate fixation were included. Zoledronic acid (5mg) was injected intravenously between 3 and 5 days after surgery. BMD scores after 1 year of operation were compared with the initial scores. Bone turnover markers were measured before surgery, after 3 months, and after 1 year. Radiological follow-up was performed every 2 weeks until the bone union and at 1 year postoperatively. Clinical outcome indicators were measured one year after surgery, and the occurrence of side effects was observed. Result: Total of 23 patients were included, with a lumbar BMD T score of -2.89±0.2 before surgery to -2.27±0.3 one year after surgery (p=0.012) and a femoral neck BMD T score of -2.45±0.3 before surgery to -2.36±0.3 (p=0.041) after one year, and all were statistically significant. Measured as bone resorption markers, serum CTX-1 was 337.43±10.4 pg/mL before surgery, 160.86±8.7 pg/mL (p=0.022) after three months, and 250.12±12.7 pg/mL (p=0.031) after one year. Urinary NTX-1 was 39.24±2.2 ng/mL before surgery, 24.46±1.2 ng/mL (p=0.014) after three months and 30.35±1.6 ng/mL (p=0.042) after one year. Measured as bone formation markers, serum osteocalcin was 13.04±1.1 ng/mL before surgery, 8.84±0.7 ng/mL (p=0.037) after 3 months and 11.1±0.4 ng/mL (p=0.026) after one year. Serum bone-specific ALP was 11.24±0.9 IU/L before surgery, 8.25±0.9 IU/L (p=0.036) after three months, and 10.2±0.9 IU/L (p=0.027) after one year. All were statistically significant. All cases showed bone union within an average of 6.91±0.3 weeks without any signs of failure. Complications were found in 5 out of 23 cases (21.7%), such as headache, nausea, muscle pain, and fever. Conclusion: When Zoledronic acid was used, BMD was improved in both the spine and femoral neck. This may reduce the likelihood and subsequent morbidity of additional osteoporotic fractures. This study is meaningful in that there was no difference in the duration of bone union and radiological characteristics in patients with distal radial fractures administrated with intravenous BP early after the fractures, and improvement in BMD and bone turnover indicators was measured.

Keywords: zeoldreonic acid, BMD, osteoporosis, distal radius

Procedia PDF Downloads 115
191 Development of a Sprayable Piezoelectric Material for E-Textile Applications

Authors: K. Yang, Y. Wei, M. Zhang, S. Yong, R. Torah, J. Tudor, S. Beeby

Abstract:

E-textiles are traditional textiles with integrated electronic functionality. It is an emerging innovation with numerous applications in fashion, wearable computing, health and safety monitoring, and the military and medical sectors. The piezoelectric effect is a widespread and versatile transduction mechanism used in sensor and actuator applications. Piezoelectric materials produce electric charge when stressed. Conversely, mechanical deformation occurs when an electric field is applied across the material. Lead Zirconate Titanate (PZT) is a widely used piezoceramic material which has been used to fabricate e-textiles through screen printing, electro spinning and hydrothermal synthesis. This paper explores an alternative fabrication process: Spray coating. Spray coating is a straightforward and cost effective fabrication method applicable on both flat and curved surfaces. It can also be applied selectively by spraying through a stencil which enables the required design to be realised on the substrate. This work developed a sprayable PZT based piezoelectric ink consisting of a binder (Fabink-Binder-01), PZT powder (80 % 2 µm and 20 % 0.8 µm) and acetone as a thinner. The optimised weight ratio of PZT/binder is 10:1. The components were mixed using a SpeedMixer DAC 150. The fabrication processes is as follows: 1) Screen print a UV-curable polyurethane interface layer on the textile to create a smooth textile surface. 2) Spray one layer of a conductive silver polymer ink through a pre-designed stencil and dry at 90 °C for 10 minutes to form the bottom electrode. 3) Spray three layers of the PZT ink through a pre-designed stencil and dry at 90 °C for 10 minutes for each layer to form a total thickness of ~250µm PZT layer. 4) Spray one layer of the silver ink through a pre-designed stencil on top of the PZT layer and dry at 90 °C for 10 minutes to form the top electrode. The domains of the PZT elements were aligned by polarising the material at an elevated temperature under a strong electric field. A d33 of 37 pC/N has been achieved after polarising at 90 °C for 6 minutes with an electric field of 3 MV/m. The application of the piezoelectric textile was demonstrated by fabricating a pressure sensor to switch an LED on/off. Other potential applications on e-textiles include motion sensing, energy harvesting, force sensing and a buzzer.

Keywords: piezoelectric, PZT, spray coating, pressure sensor, e-textile

Procedia PDF Downloads 465
190 A Study of Female Casino Dealers' Job Stress and Job Satisfaction: The Case of Macau

Authors: Xinrong Zong, Tao Zhang

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Macau is known as the Oriental Monte Carlo and its economy depends on gambling heavily. The dealer is the key position of the gambling industry, at the end of the fourth quarter of 2015, there were over 24,000 dealers among the 56,000 full-time employees in gambling industry. More than half of dealers were female. The dealer is also called 'Croupier', the main responsibilities of them are shuffling, dealing, processing chips, rolling dice game and inspecting play. Due to the limited land and small population of Macao, the government has not allowed hiring foreign domestic dealers since Macao developed temporary gambling industry. Therefore, local dealers enjoy special advantages but also bear the high stresses from work. From the middle of last year, with the reduced income of gambling, and the decline of mainland gamblers as well as VIP lounges, the working time of dealers increased greatly. Thus, many problems occurred in this condition, such as the rise of working pressures, psychological pressures and family-responsibility pressures, which may affect job satisfaction as well. Because of the less research of dealer satisfaction, and a lack of standing on feminine perspective to analyze female dealers, this study will focus on investigating the relationship between working pressure and job satisfaction from feminine view. Several issues will be discussed specifically: firstly, to understand current situation of the working pressures and job satisfactions of female dealers in different ages; secondly, to research if there is any relevance between working pressures and job satisfactions of female dealers in different ages; thirdly, to find out the relationship between dealers' working pressures and job satisfactions in different ages. This paper combined qualitative approach with quantitative approach selected samples by convenient sampling. The research showed the female dealers from diverse ages have different kinds of working pressures; second, job satisfactions of the female dealers in different ages are dissimilar; moreover, there is negative correlation between working pressure and job satisfaction of female dealer in different ages' groups; last but not the least, working pressure has a significant negative impact on job satisfaction. The research result will provide a reference value for the Macau gambling business. It is a pattern to improve dealers' working environment, to increase employees' job satisfaction, as well as to offer tourists a better service, which can help to attract more and more visitors from a good image of Macau gaming and tourism.

Keywords: female dealers, job satisfaction, working pressure, Macau

Procedia PDF Downloads 297
189 Exploring an Exome Target Capture Method for Cross-Species Population Genetic Studies

Authors: Benjamin A. Ha, Marco Morselli, Xinhui Paige Zhang, Elizabeth A. C. Heath-Heckman, Jonathan B. Puritz, David K. Jacobs

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Next-generation sequencing has enhanced the ability to acquire massive amounts of sequence data to address classic population genetic questions for non-model organisms. Targeted approaches allow for cost effective or more precise analyses of relevant sequences; although, many such techniques require a known genome and it can be costly to purchase probes from a company. This is challenging for non-model organisms with no published genome and can be expensive for large population genetic studies. Expressed exome capture sequencing (EecSeq) synthesizes probes in the lab from expressed mRNA, which is used to capture and sequence the coding regions of genomic DNA from a pooled suite of samples. A normalization step produces probes to recover transcripts from a wide range of expression levels. This approach offers low cost recovery of a broad range of genes in the genome. This research project expands on EecSeq to investigate if mRNA from one taxon may be used to capture relevant sequences from a series of increasingly less closely related taxa. For this purpose, we propose to use the endangered Northern Tidewater goby, Eucyclogobius newberryi, a non-model organism that inhabits California coastal lagoons. mRNA will be extracted from E. newberryi to create probes and capture exomes from eight other taxa, including the more at-risk Southern Tidewater goby, E. kristinae, and more divergent species. Captured exomes will be sequenced, analyzed bioinformatically and phylogenetically, then compared to previously generated phylogenies across this group of gobies. This will provide an assessment of the utility of the technique in cross-species studies and for analyzing low genetic variation within species as is the case for E. kristinae. This method has potential applications to provide economical ways to expand population genetic and evolutionary biology studies for non-model organisms.

Keywords: coastal lagoons, endangered species, non-model organism, target capture method

Procedia PDF Downloads 190
188 Inverted Geometry Ceramic Insulators in High Voltage Direct Current Electron Guns for Accelerators

Authors: C. Hernandez-Garcia, P. Adderley, D. Bullard, J. Grames, M. A. Mamun, G. Palacios-Serrano, M. Poelker, M. Stutzman, R. Suleiman, Y. Wang, , S. Zhang

Abstract:

High-energy nuclear physics experiments performed at the Jefferson Lab (JLab) Continuous Electron Beam Accelerator Facility require a beam of spin-polarized ps-long electron bunches. The electron beam is generated when a circularly polarized laser beam illuminates a GaAs semiconductor photocathode biased at hundreds of kV dc inside an ultra-high vacuum chamber. The photocathode is mounted on highly polished stainless steel electrodes electrically isolated by means of a conical-shape ceramic insulator that extends into the vacuum chamber, serving as the cathode electrode support structure. The assembly is known as a dc photogun, which has to simultaneously meet the following criteria: high voltage to manage space charge forces within the electron bunch, ultra-high vacuum conditions to preserve the photocathode quantum efficiency, no field emission to prevent gas load when field emitted electrons impact the vacuum chamber, and finally no voltage breakdown for robust operation. Over the past decade, JLab has tested and implemented the use of inverted geometry ceramic insulators connected to commercial high voltage cables to operate a photogun at 200kV dc with a 10 cm long insulator, and a larger version at 300kV dc with 20 cm long insulator. Plans to develop a third photogun operating at 400kV dc to meet the stringent requirements of the proposed International Linear Collider are underway at JLab, utilizing even larger inverted insulators. This contribution describes approaches that have been successful in solving challenging problems related to breakdown and field emission, such as triple-point junction screening electrodes, mechanical polishing to achieve mirror-like surface finish and high voltage conditioning procedures with Kr gas to extinguish field emission.

Keywords: electron guns, high voltage techniques, insulators, vacuum insulation

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187 The Thinking of Dynamic Formulation of Rock Aging Agent Driven by Data

Authors: Longlong Zhang, Xiaohua Zhu, Ping Zhao, Yu Wang

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The construction of mines, railways, highways, water conservancy projects, etc., have formed a large number of high steep slope wounds in China. Under the premise of slope stability and safety, the minimum cost, green and close to natural wound space repair, has become a new problem. Nowadays, in situ element testing and analysis, monitoring, field quantitative factor classification, and assignment evaluation will produce vast amounts of data. Data processing and analysis will inevitably differentiate the morphology, mineral composition, physicochemical properties between rock wounds, by which to dynamically match the appropriate techniques and materials for restoration. In the present research, based on the grid partition of the slope surface, tested the content of the combined oxide of rock mineral (SiO₂, CaO, MgO, Al₂O₃, Fe₃O₄, etc.), and classified and assigned values to the hardness and breakage of rock texture. The data of essential factors are interpolated and normalized in GIS, which formed the differential zoning map of slope space. According to the physical and chemical properties and spatial morphology of rocks in different zones, organic acids (plant waste fruit, fruit residue, etc.), natural mineral powder (zeolite, apatite, kaolin, etc.), water-retaining agent, and plant gum (melon powder) were mixed in different proportions to form rock aging agents. To spray the aging agent with different formulas on the slopes in different sections can affectively age the fresh rock wound, providing convenience for seed implantation, and reducing the transformation of heavy metals in the rocks. Through many practical engineering practices, a dynamic data platform of rock aging agent formula system is formed, which provides materials for the restoration of different slopes. It will also provide a guideline for the mixed-use of various natural materials to solve the complex, non-uniformity ecological restoration problem.

Keywords: data-driven, dynamic state, high steep slope, rock aging agent, wounds

Procedia PDF Downloads 115
186 Translation and Transculturality in Contemporary Chinese Art: A Case Study of Gu Wenda’s 'Forest of Stone Steles' and 'United Nations: Temple of Heaven'

Authors: Rui Zhang

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Translation has been elevated to one of the key notions in contemporary cultural discourse for a wide range of fields. It focuses not only on communication or transmission of meaning between different languages, but also on ways in which the very act of translation can be understood as a metaphor for cultural process. In recent years, the notion of translation is employed by some contemporary Chinese artists in a conceptual way, whose works contribute to constructing/deconstructing global/local cultural discourse and their own cultural identities. This study examines two artworks by contemporary Chinese artist Gu Wenda from a translational perspective, namely Forest of Stone Steles - Retranslation & Rewriting of Tang Poetry and United Nations - China Monument: Temple of Heaven, aiming to broaden the scope of Translation Studies to investigate visual culture and enrich methodological approach to contemporary Chinese art. Focusing on the relationship between translation, visuality and materiality in these two works, this study explores the nature of translation as part of the production of cultural discourse in the age of globalization as well as a way of establishing cultural identity. Gu Wenda, one of the most prestigious artists in contemporary China, is considered a pioneer in ‘85 Art Movement of China, and thereafter he went abroad for his artistic pursuits. His transnational experience enriches his cultural identity and the underlying discourse constructed/deconstructed in many of his works. In the two works already mentioned, the concept of translation is deployed by Gu Wenda on both linguistic level and metaphorical level for artistic expression. These two works produce discourses in which the artist’s perception of cultural identity in a transnational context is articulated by the tension between source text and target text. Based on the conceptual framework of cultural identity proposed by Stuart Hall, analyses of Gu Wenda’s cultural identity revealed through translation in these two works are centred on two axes, i.e., the axis of similarity and continuity with Chinese intellectual culture and the axis of difference and rupture with it, and the dialogic relationship between these two vectors. It argues that besides serving as a means of constructing visuality in the two works, translation metaphorizes Gu Wenda’s journey from overcoming his cultural identity anxiety to re-establishing a transcultural identity embedded in the underlying discourse.

Keywords: contemporary Chinese art, cultural identity, transculturality, translation

Procedia PDF Downloads 497
185 Predicting Personality and Psychological Distress Using Natural Language Processing

Authors: Jihee Jang, Seowon Yoon, Gaeun Son, Minjung Kang, Joon Yeon Choeh, Kee-Hong Choi

Abstract:

Background: Self-report multiple choice questionnaires have been widely utilized to quantitatively measure one’s personality and psychological constructs. Despite several strengths (e.g., brevity and utility), self-report multiple-choice questionnaires have considerable limitations in nature. With the rise of machine learning (ML) and Natural language processing (NLP), researchers in the field of psychology are widely adopting NLP to assess psychological constructs to predict human behaviors. However, there is a lack of connections between the work being performed in computer science and that psychology due to small data sets and unvalidated modeling practices. Aims: The current article introduces the study method and procedure of phase II, which includes the interview questions for the five-factor model (FFM) of personality developed in phase I. This study aims to develop the interview (semi-structured) and open-ended questions for the FFM-based personality assessments, specifically designed with experts in the field of clinical and personality psychology (phase 1), and to collect the personality-related text data using the interview questions and self-report measures on personality and psychological distress (phase 2). The purpose of the study includes examining the relationship between natural language data obtained from the interview questions, measuring the FFM personality constructs, and psychological distress to demonstrate the validity of the natural language-based personality prediction. Methods: The phase I (pilot) study was conducted on fifty-nine native Korean adults to acquire the personality-related text data from the interview (semi-structured) and open-ended questions based on the FFM of personality. The interview questions were revised and finalized with the feedback from the external expert committee, consisting of personality and clinical psychologists. Based on the established interview questions, a total of 425 Korean adults were recruited using a convenience sampling method via an online survey. The text data collected from interviews were analyzed using natural language processing. The results of the online survey, including demographic data, depression, anxiety, and personality inventories, were analyzed together in the model to predict individuals’ FFM of personality and the level of psychological distress (phase 2).

Keywords: personality prediction, psychological distress prediction, natural language processing, machine learning, the five-factor model of personality

Procedia PDF Downloads 79
184 Monitoring Large-Coverage Forest Canopy Height by Integrating LiDAR and Sentinel-2 Images

Authors: Xiaobo Liu, Rakesh Mishra, Yun Zhang

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Continuous monitoring of forest canopy height with large coverage is essential for obtaining forest carbon stocks and emissions, quantifying biomass estimation, analyzing vegetation coverage, and determining biodiversity. LiDAR can be used to collect accurate woody vegetation structure such as canopy height. However, LiDAR’s coverage is usually limited because of its high cost and limited maneuverability, which constrains its use for dynamic and large area forest canopy monitoring. On the other hand, optical satellite images, like Sentinel-2, have the ability to cover large forest areas with a high repeat rate, but they do not have height information. Hence, exploring the solution of integrating LiDAR data and Sentinel-2 images to enlarge the coverage of forest canopy height prediction and increase the prediction repeat rate has been an active research topic in the environmental remote sensing community. In this study, we explore the potential of training a Random Forest Regression (RFR) model and a Convolutional Neural Network (CNN) model, respectively, to develop two predictive models for predicting and validating the forest canopy height of the Acadia Forest in New Brunswick, Canada, with a 10m ground sampling distance (GSD), for the year 2018 and 2021. Two 10m airborne LiDAR-derived canopy height models, one for 2018 and one for 2021, are used as ground truth to train and validate the RFR and CNN predictive models. To evaluate the prediction performance of the trained RFR and CNN models, two new predicted canopy height maps (CHMs), one for 2018 and one for 2021, are generated using the trained RFR and CNN models and 10m Sentinel-2 images of 2018 and 2021, respectively. The two 10m predicted CHMs from Sentinel-2 images are then compared with the two 10m airborne LiDAR-derived canopy height models for accuracy assessment. The validation results show that the mean absolute error (MAE) for year 2018 of the RFR model is 2.93m, CNN model is 1.71m; while the MAE for year 2021 of the RFR model is 3.35m, and the CNN model is 3.78m. These demonstrate the feasibility of using the RFR and CNN models developed in this research for predicting large-coverage forest canopy height at 10m spatial resolution and a high revisit rate.

Keywords: remote sensing, forest canopy height, LiDAR, Sentinel-2, artificial intelligence, random forest regression, convolutional neural network

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183 Plasma-Assisted Decomposition of Cyclohexane in a Dielectric Barrier Discharge Reactor

Authors: Usman Dahiru, Faisal Saleem, Kui Zhang, Adam Harvey

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Volatile organic compounds (VOCs) are atmospheric contaminants predominantly derived from petroleum spills, solvent usage, agricultural processes, automobile, and chemical processing industries, which can be detrimental to the environment and human health. Environmental problems such as the formation of photochemical smog, organic aerosols, and global warming are associated with VOC emissions. Research showed a clear relationship between VOC emissions and cancer. In recent years, stricter emission regulations, especially in industrialized countries, have been put in place around the world to restrict VOC emissions. Non-thermal plasmas (NTPs) are a promising technology for reducing VOC emissions by converting them into less toxic/environmentally friendly species. The dielectric barrier discharge (DBD) plasma is of interest due to its flexibility, moderate capital cost, and ease of operation under ambient conditions. In this study, a dielectric barrier discharge (DBD) reactor has been developed for the decomposition of cyclohexane (as a VOC model compound) using nitrogen, dry, and humidified air carrier gases. The effect of specific input energy (1.2-3.0 kJ/L), residence time (1.2-2.3 s) and concentration (220-520 ppm) were investigated. It was demonstrated that the removal efficiency of cyclohexane increased with increasing plasma power and residence time. The removal of cyclohexane decreased with increasing cyclohexane inlet concentration at fixed plasma power and residence time. The decomposition products included H₂, CO₂, H₂O, lower hydrocarbons (C₁-C₅) and solid residue. The highest removal efficiency (98.2%) was observed at specific input energy of 3.0 kJ/L and a residence time of 2.3 s in humidified air plasma. The effect of humidity was investigated to determine whether it could reduce the formation of solid residue in the DBD reactor. It was observed that the solid residue completely disappeared in humidified air plasma. Furthermore, the presence of OH radicals due to humidification not only increased the removal efficiency of cyclohexane but also improves product selectivity. This work demonstrates that cyclohexane can be converted to smaller molecules by a dielectric barrier discharge (DBD) non-thermal plasma reactor by varying plasma power (SIE), residence time, reactor configuration, and carrier gas.

Keywords: cyclohexane, dielectric barrier discharge reactor, non-thermal plasma, removal efficiency

Procedia PDF Downloads 136
182 Cyclic Etching Process Using Inductively Coupled Plasma for Polycrystalline Diamond on AlGaN/GaN Heterostructure

Authors: Haolun Sun, Ping Wang, Mei Wu, Meng Zhang, Bin Hou, Ling Yang, Xiaohua Ma, Yue Hao

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Gallium nitride (GaN) is an attractive material for next-generation power devices. It is noted that the performance of GaN-based high electron mobility transistors (HEMTs) is always limited by the self-heating effect. In response to the problem, integrating devices with polycrystalline diamond (PCD) has been demonstrated to be an efficient way to alleviate the self-heating issue of the GaN-based HEMTs. Among all the heat-spreading schemes, using PCD to cap the epitaxial layer before the HEMTs process is one of the most effective schemes. Now, the mainstream method of fabricating the PCD-capped HEMTs is to deposit the diamond heat-spreading layer on the AlGaN surface, which is covered by a thin nucleation dielectric/passivation layer. To achieve the pattern etching of the diamond heat spreader and device preparation, we selected SiN as the hard mask for diamond etching, which was deposited by plasma-enhanced chemical vapor deposition (PECVD). The conventional diamond etching method first uses F-based etching to remove the SiN from the special window region, followed by using O₂/Ar plasma to etch the diamond. However, the results of the scanning electron microscope (SEM) and focused ion beam microscopy (FIB) show that there are lots of diamond pillars on the etched diamond surface. Through our study, we found that it was caused by the high roughness of the diamond surface and the existence of the overlap between the diamond grains, which makes the etching of the SiN hard mask insufficient and leaves micro-masks on the diamond surface. Thus, a cyclic etching method was proposed to solve the problem of the residual SiN, which was left in the F-based etching. We used F-based etching during the first step to remove the SiN hard mask in the specific region; then, the O₂/Ar plasma was introduced to etch the diamond in the corresponding region. These two etching steps were set as one cycle. After the first cycle, we further used cyclic etching to clear the pillars, in which the F-based etching was used to remove the residual SiN, and then the O₂/Ar plasma was used to etch the diamond. Whether to take the next cyclic etching depends on whether there are still SiN micro-masks left. By using this method, we eventually achieved the self-terminated etching of the diamond and the smooth surface after the etching. These results demonstrate that the cyclic etching method can be successfully applied to the integrated preparation of polycrystalline diamond thin films and GaN HEMTs.

Keywords: AlGaN/GaN heterojunction, O₂/Ar plasma, cyclic etching, polycrystalline diamond

Procedia PDF Downloads 134
181 The Psychosocial Issues and Support Needs of Patients with Chronic Kidney Disease Undergoing Hemodialysis: A Qualitative Study from Nepal

Authors: Akriti Kafle Baral, Ruixing Zhang, Dzifa K Lalit, Manthar M Alli

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Introduction: Hemodialysis is the most common type of dialysis globally approximately million are reported to receive this type of dialysis. Psychosocial issues in hemodialysis are the psychological and socioeconomic burdens emanating from the initiation and course of treatment and have the potential for gross deterioration in the quality of life and general well-being of patients. Understanding the psychosocial issues and needs of patients undergoing hemodialysis could pave the way for comprehensive support and therapies designed to reduce stress, improve social support, and foster mental resilience. Objectives: The aim of this study was to explore the psychosocial issues and support needs of patients undergoing hemodialysis at a tertiary care center in Nepal. Methods: A qualitative descriptive study was conducted among 20 purposefully selected patients attending hemodialysis treatment at Pokhara Academy of Health Sciences, Nepal. Data was analyzed via thematic analysis. Results: The study resulted in three major themes which included Emotional, psychological, and spiritual struggles, Social and economic impacts, and Support and information needs. Moreover, 16 sub-themes emerged which are Frustration with daily life, Constant fear of death, Thoughts of self-harm, Perceived Burden on Family, Sense of Divine Punishment, Sense of Unfairness, Fear about future uncertainties, Social avoidance, Social stigmatization, Loss of employment, Financial strain, Transportation challenges, Need for early, clear and comprehensive information, Need for support and reassurance from family, Support through peer connections, and Reassurance from healthcare providers. Conclusion: The findings of this study indicate that patients undergoing hemodialysis in Nepal experience numerous hardships and multifaceted struggles that require support from different dimensions. Establishing robust support systems that include family involvement, peer networks, and effective communication from healthcare professionals can significantly mitigate feelings of anxiety and isolation.

Keywords: hemodialysis, psychosocial issues, support needs, chronic kidney disease, end stage renal disease, Nepal

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180 Stochastic Fleet Sizing and Routing in Drone Delivery

Authors: Amin Karimi, Lele Zhang, Mark Fackrell

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Rural-to-urban population migrations are a global phenomenon, with projections indicating that by 2050, 68% of the world's population will inhabit densely populated urban centers. Concurrently, the popularity of e-commerce shopping has surged, evidenced by a 51% increase in total e-commerce sales from 2017 to 2021. Consequently, distribution and logistics systems, integral to effective supply chain management, confront escalating hurdles in efficiently delivering and distributing products within bustling urban environments. Additionally, events like environmental challenges and the COVID-19 pandemic have indicated that decision-makers are facing numerous sources of uncertainty. Therefore, to design an efficient and reliable logistics system, uncertainty must be considered. In this study, it examine fleet sizing and routing while considering uncertainty in demand rate. Fleet sizing is typically a strategic-level decision, while routing is an operational-level one. In this study, a carrier must make two types of decisions: strategic-level decisions regarding the number and types of drones to be purchased, and operational-level decisions regarding planning routes based on available fleet and realized demand. If the available fleets are insufficient to serve some customers, the carrier must outsource that delivery at a relatively high cost, calculated per order. With this hierarchy of decisions, it can model the problem using two-stage stochastic programming. The first-stage decisions involve planning the number and type of drones to be purchased, while the second-stage decisions involve planning routes. To solve this model, it employ logic-based benders decomposition, which decomposes the problem into a master problem and a set of sub-problems. The master problem becomes a mixed integer programming model to find the best fleet sizing decisions, and the sub-problems become capacitated vehicle routing problems considering battery status. Additionally, it assume a heterogeneous fleet based on load and battery capacity, and it consider that battery health deteriorates over time as it plan for multiple periods.

Keywords: drone-delivery, stochastic demand, VRP, fleet sizing

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179 Revolutions and Cyclic Patterns in Chinese Town Planning: The Case-Study of Shenzhen

Authors: Domenica Bona

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Colin Chant and David Goodman argue that historians of Chinese pre-industrial cities tend to underestimate revolutions and overestimate cyclic patterns: periods of peace and prosperity in the earl part of each d nast , followed b peasants’ rebellions and upheavals. Boyd described these cyclic patterns as part of the background of Chinese town planning and architecture. Thus old ideals of city planning-square plan, southward orientation and a palace along the central axis - are revived again and again in the ascendant phases of several d nastic c cles (e.g. Chang’an, Kaifen, and Beijing). Along this line of thought, m paper questions the relationship between the “magic square rule” and modern Chinese urban- planning. As a matter of fact, the classical theme of “cosmic Taoist urbanism” is still a reference for planning cities and new urban developments, whenever there is the intention to express nationalist ideals and “cultural straightforwardness.” Besides, some case studies can be related to “modern d nasties”: the first Republic under the Kuo Min Tang, the red People’s Republic and the post-Maoist open country of Deng Xiao Ping. Considering the project for the new capital of Nanjing in the Thirties, Beijing’s Tianan Men area in the ifties, and Shenzhen’s utian CBD in late 20th century, I argue that cyclic patterns are still in place, though with deformations related to westernization, private interests and lack of spirituality. How far new Chinese cities are - or simply seem to be - westernized? Symbolism, invisible frameworks, repeating features and behavioural patterns make urban China just “superficiall” western. This can be well noticed in cities previousl occupied b foreigners, like Hong Kong, or in newly founded ones, like Shenzhen, where both Asians and non-Asian people can feel the gender-shift from New-York-like landscapes to something else. Current planning in main metropolitan areas shows a blurred relationship between public policies and private investments: two levels of decisions and actions, one addressing the larger scale and infrastructures, the other concerning the micro scale and development of single plots. While zoning is instrumental in this process, master plans are often laid out over a very poor cartography, so much that any relation between the formal characters of new cities and the centuries-old structure of the related territory gets lost.

Keywords: China, contemporary cities, cultural heritage, shenzhen, urban planning

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178 Application Research of Stilbene Crystal for the Measurement of Accelerator Neutron Sources

Authors: Zhao Kuo, Chen Liang, Zhang Zhongbing, Ruan Jinlu. He Shiyi, Xu Mengxuan

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Stilbene, C₁₄H₁₂, is well known as one of the most useful organic scintillators for pulse shape discrimination (PSD) technique for its good scintillation properties. An on-line acquisition system and an off-line acquisition system were developed with several CAMAC standard plug-ins, NIM plug-ins, neutron/γ discriminating plug-in named 2160A and a digital oscilloscope with high sampling rate respectively for which stilbene crystals and photomultiplier tube detectors (PMT) as detector for accelerator neutron sources measurement carried out in China Institute of Atomic Energy. Pulse amplitude spectrums and charge amplitude spectrums were real-time recorded after good neutron/γ discrimination whose best PSD figure-of-merits (FoMs) are 1.756 for D-D accelerator neutron source and 1.393 for D-T accelerator neutron source. The probability of neutron events in total events was 80%, and neutron detection efficiency was 5.21% for D-D accelerator neutron sources, which were 50% and 1.44% for D-T accelerator neutron sources after subtracting the background of scattering observed by the on-line acquisition system. Pulse waveform signals were acquired by the off-line acquisition system randomly while the on-line acquisition system working. The PSD FoMs obtained by the off-line acquisition system were 2.158 for D-D accelerator neutron sources and 1.802 for D-T accelerator neutron sources after waveform digitization off-line processing named charge integration method for just 1000 pulses. In addition, the probabilities of neutron events in total events obtained by the off-line acquisition system matched very well with the probabilities of the on-line acquisition system. The pulse information recorded by the off-line acquisition system could be repetitively used to adjust the parameters or methods of PSD research and obtain neutron charge amplitude spectrums or pulse amplitude spectrums after digital analysis with a limited number of pulses. The off-line acquisition system showed equivalent or better measurement effects compared with the online system with a limited number of pulses which indicated a feasible method based on stilbene crystals detectors for the measurement of prompt neutrons neutron sources like prompt accelerator neutron sources emit a number of neutrons in a short time.

Keywords: stilbene crystal, accelerator neutron source, neutron / γ discrimination, figure-of-merits, CAMAC, waveform digitization

Procedia PDF Downloads 187
177 The Relationship between Body Positioning and Badminton Smash Quality

Authors: Gongbing Shan, Shiming Li, Zhao Zhang, Bingjun Wan

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Badminton originated in ancient civilizations in Europe and Asia more than 2000 years ago. Presently, it is played almost everywhere with estimated 220 million people playing badminton regularly, ranging from professionals to recreational players; and it is the second most played sport in the world after soccer. In Asia, the popularity of badminton and involvement of people surpass soccer. Unfortunately, scientific researches on badminton skills are hardly proportional to badminton’s popularity. A search of literature has shown that the literature body of biomechanical investigations is relatively small. One of the dominant skills in badminton is the forehand overhead smash, which consists of 1/5 attacks during games. Empirical evidences show that one has to adjust the body position in relation to the coming shuttlecock to produce a powerful and accurate smash. Therefore, positioning is a fundamental aspect influencing smash quality. A search of literature has shown that there is a dearth/lack of study on this fundamental aspect. The goals of this study were to determine the influence of positioning and training experience on smash quality in order to discover information that could help learn/acquire the skill. Using a 10-camera, 3D motion capture system (VICON MX, 200 frames/s) and 15-segment, full-body biomechanical model, 14 skilled and 15 novice players were measured and analyzed. Results have revealed that the body positioning has direct influence on the quality of a smash, especially on shuttlecock release angle and clearance height (passing over the net) of offensive players. The results also suggest that, for training a proper positioning, one could conduct a self-selected comfort position towards a statically hanged shuttlecock and then step one foot back – a practical reference marker for learning. This perceptional marker could be applied in guiding the learning and training of beginners. As one gains experience through repetitive training, improved limbs’ coordination would increase smash quality further. The researchers hope that the findings will benefit practitioners for developing effective training programs for beginners.

Keywords: 3D motion analysis, biomechanical modeling, shuttlecock release speed, shuttlecock release angle, clearance height

Procedia PDF Downloads 498
176 Artificial Neural Network Based Parameter Prediction of Miniaturized Solid Rocket Motor

Authors: Hao Yan, Xiaobing Zhang

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The working mechanism of miniaturized solid rocket motors (SRMs) is not yet fully understood. It is imperative to explore its unique features. However, there are many disadvantages to using common multi-objective evolutionary algorithms (MOEAs) in predicting the parameters of the miniaturized SRM during its conceptual design phase. Initially, the design variables and objectives are constrained in a lumped parameter model (LPM) of this SRM, which leads to local optima in MOEAs. In addition, MOEAs require a large number of calculations due to their population strategy. Although the calculation time for simulating an LPM just once is usually less than that of a CFD simulation, the number of function evaluations (NFEs) is usually large in MOEAs, which makes the total time cost unacceptably long. Moreover, the accuracy of the LPM is relatively low compared to that of a CFD model due to its assumptions. CFD simulations or experiments are required for comparison and verification of the optimal results obtained by MOEAs with an LPM. The conceptual design phase based on MOEAs is a lengthy process, and its results are not precise enough due to the above shortcomings. An artificial neural network (ANN) based parameter prediction is proposed as a way to reduce time costs and improve prediction accuracy. In this method, an ANN is used to build a surrogate model that is trained with a 3D numerical simulation. In design, the original LPM is replaced by a surrogate model. Each case uses the same MOEAs, in which the calculation time of the two models is compared, and their optimization results are compared with 3D simulation results. Using the surrogate model for the parameter prediction process of the miniaturized SRMs results in a significant increase in computational efficiency and an improvement in prediction accuracy. Thus, the ANN-based surrogate model does provide faster and more accurate parameter prediction for an initial design scheme. Moreover, even when the MOEAs converge to local optima, the time cost of the ANN-based surrogate model is much lower than that of the simplified physical model LPM. This means that designers can save a lot of time during code debugging and parameter tuning in a complex design process. Designers can reduce repeated calculation costs and obtain accurate optimal solutions by combining an ANN-based surrogate model with MOEAs.

Keywords: artificial neural network, solid rocket motor, multi-objective evolutionary algorithm, surrogate model

Procedia PDF Downloads 90
175 Machine Learning in Gravity Models: An Application to International Recycling Trade Flow

Authors: Shan Zhang, Peter Suechting

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Predicting trade patterns is critical to decision-making in public and private domains, especially in the current context of trade disputes among major economies. In the past, U.S. recycling has relied heavily on strong demand for recyclable materials overseas. However, starting in 2017, a series of new recycling policies (bans and higher inspection standards) was enacted by multiple countries that were the primary importers of recyclables from the U.S. prior to that point. As the global trade flow of recycling shifts, some new importers, mostly developing countries in South and Southeast Asia, have been overwhelmed by the sheer quantities of scrap materials they have received. As the leading exporter of recyclable materials, the U.S. now has a pressing need to build its recycling industry domestically. With respect to the global trade in scrap materials used for recycling, the interest in this paper is (1) predicting how the export of recyclable materials from the U.S. might vary over time, and (2) predicting how international trade flows for recyclables might change in the future. Focusing on three major recyclable materials with a history of trade, this study uses data-driven and machine learning (ML) algorithms---supervised (shrinkage and tree methods) and unsupervised (neural network method)---to decipher the international trade pattern of recycling. Forecasting the potential trade values of recyclables in the future could help importing countries, to which those materials will shift next, to prepare related trade policies. Such policies can assist policymakers in minimizing negative environmental externalities and in finding the optimal amount of recyclables needed by each country. Such forecasts can also help exporting countries, like the U.S understand the importance of healthy domestic recycling industry. The preliminary result suggests that gravity models---in addition to particular selection macroeconomic predictor variables--are appropriate predictors of the total export value of recyclables. With the inclusion of variables measuring aspects of the political conditions (trade tariffs and bans), predictions show that recyclable materials are shifting from more policy-restricted countries to less policy-restricted countries in international recycling trade. Those countries also tend to have high manufacturing activities as a percentage of their GDP.

Keywords: environmental economics, machine learning, recycling, international trade

Procedia PDF Downloads 168
174 Systematic Evaluation of Convolutional Neural Network on Land Cover Classification from Remotely Sensed Images

Authors: Eiman Kattan, Hong Wei

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In using Convolutional Neural Network (CNN) for classification, there is a set of hyperparameters available for the configuration purpose. This study aims to evaluate the impact of a range of parameters in CNN architecture i.e. AlexNet on land cover classification based on four remotely sensed datasets. The evaluation tests the influence of a set of hyperparameters on the classification performance. The parameters concerned are epoch values, batch size, and convolutional filter size against input image size. Thus, a set of experiments were conducted to specify the effectiveness of the selected parameters using two implementing approaches, named pertained and fine-tuned. We first explore the number of epochs under several selected batch size values (32, 64, 128 and 200). The impact of kernel size of convolutional filters (1, 3, 5, 7, 10, 15, 20, 25 and 30) was evaluated against the image size under testing (64, 96, 128, 180 and 224), which gave us insight of the relationship between the size of convolutional filters and image size. To generalise the validation, four remote sensing datasets, AID, RSD, UCMerced and RSCCN, which have different land covers and are publicly available, were used in the experiments. These datasets have a wide diversity of input data, such as number of classes, amount of labelled data, and texture patterns. A specifically designed interactive deep learning GPU training platform for image classification (Nvidia Digit) was employed in the experiments. It has shown efficiency in both training and testing. The results have shown that increasing the number of epochs leads to a higher accuracy rate, as expected. However, the convergence state is highly related to datasets. For the batch size evaluation, it has shown that a larger batch size slightly decreases the classification accuracy compared to a small batch size. For example, selecting the value 32 as the batch size on the RSCCN dataset achieves the accuracy rate of 90.34 % at the 11th epoch while decreasing the epoch value to one makes the accuracy rate drop to 74%. On the other extreme, setting an increased value of batch size to 200 decreases the accuracy rate at the 11th epoch is 86.5%, and 63% when using one epoch only. On the other hand, selecting the kernel size is loosely related to data set. From a practical point of view, the filter size 20 produces 70.4286%. The last performed image size experiment shows a dependency in the accuracy improvement. However, an expensive performance gain had been noticed. The represented conclusion opens the opportunities toward a better classification performance in various applications such as planetary remote sensing.

Keywords: CNNs, hyperparamters, remote sensing, land cover, land use

Procedia PDF Downloads 169
173 Research on the Overall Protection of Historical Cities Based on the 'City Image' in Ancient Maps: Take the Ancient City of Shipu, Zhejiang, China as an Example

Authors: Xiaoya Yi, Yi He, Zhao Lu, Yang Zhang

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In the process of rapid urbanization, many historical cities have undergone excessive demolition and construction under the protection and renewal mechanism. The original pattern of the city has been changed, the urban context has been cut off, and historical features have gradually been lost. The historical city gradually changed into the form of decentralization and fragmentation. The understanding of the ancient city includes two levels. The first one refers to the ancient city on the physical space, which defined an ancient city by its historic walls. The second refers to the public perception of the image, which is derived from people's spatial identification of the ancient city. In ancient China, people draw maps to show their way of understanding the city. Starting from ancient maps and exploring the spatial characteristics of traditional Chinese cities from the perspective of urban imagery is a key clue to understanding the spatial characteristics of historical cities on an overall level. The spatial characteristics of the urban image presented by the ancient map are summarized into two levels by typology. The first is the spatial pattern composed of the center, axis and boundary. The second is the space element that contains the city, street, and sign system. Taking the ancient city of Shipu as a typical case, the "city image" in the ancient map is analyzed as a prototype, and it is projected into the current urban space. The research found that after a long period of evolution, the historical spatial pattern of the ancient city has changed from “dominant” to “recessive control”, and the historical spatial elements are non-centralized and fragmented. The wall that serves as the boundary of the ancient city is transformed into “fragmentary remains”, the streets and lanes that serve as the axis of the ancient city are transformed into “structural remains”, and the symbols of the ancient city center are transformed into “site remains”. Based on this, the paper proposed the methods of controlling the protection of land boundaries, the protecting of the streets and lanes, and the selective restoring of the city wall system and the sign system by accurate assessment. In addition, this paper emphasizes the continuity of the ancient city's traditional spatial pattern and attempts to explore a holistic conservation method of the ancient city in the modern context.

Keywords: ancient city protection, ancient maps, Shipu ancient city, urban intention

Procedia PDF Downloads 128
172 Analysis on the Effectiveness of the "Three-Exemption" Policy Aimed at Promoting Unpaid Blood Donation in Zhejiang

Authors: Ni Tang, Jinping Zhang

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An effective and sustainable volunteer team is needed to create a more available blood supply system. In order to promote the sustainable development of blood donation in Zhejiang Province, China, a “three-exemption” policy was proposed in 2014: blood donors who received the National Award for unpaid blood donation may government-invested and funded parks, scenic spots and other places for free, visit non-profit medical institutions for free outpatient fees, and be exempted from urban public transportation fees. As the policy has been in place for seven years, this study evaluated the effectiveness of the policy by comparing the increasing rate of blood donation in Hangzhou (capital city of Zhejiang) before and after the policy using the intermittent time series analysis. The blood donation in Anhui, a Province near Zhejiang, was also compared as a negative control. Blood donation data from 2012 to 2018 were obtained from the donation center's official websites. The increasing rate of blood donation volume since 2012 in Hangzhou is 34.37 units/month, and after 2014, the increasing rate additionally increases 71.69 (p=0.1442), which indicating a statistically non-significant change after the policy. While as a negative control, in Anhui, the increasing rate of blood donation volume since 2012 is -163.3 unit/month, and the increasing rate additionally increases 167.2 (p=5.63e-07) after 2014. The result shows that the three-exemption policy had a certain level of impact on encouraging volunteers to donate blood, but the effect was not substantial. One possible reason for the ineffectiveness of the policy might be a lack of public awareness of the policy. On the other hand, this policy mainly waived unnecessary life expenses, such as fares and scenic entrance fees, and requires a certain number of blood donations, registration procedures, and blood donation certificates. Perhaps, reducing life-related expenses such as oil, water and electricity, could better attract people to participate in blood donation. This current study on the three-exemption policy provides a new direction for promoting people's blood donation. Incentive policies may require greater publicity and incentives. In order to better ensure the operation of the blood donation system, other policies, especially incentive policies, should be further explored.

Keywords: blood donation, policy, Zhejiang, unpaid blood donation, three-exemption policy

Procedia PDF Downloads 210
171 Departing beyond the Orthodoxy: An Integrative Review and Future Research Avenues of Human Capital Resources Theory

Authors: Long Zhang, Ian Hampson, Loretta O' Donnell

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Practitioners in various industries, especially in the finance industry that conventionally benefit from financial capital and resources, appear to be increasingly aware of the importance of human capital resources (HCR) after the 2008 Global Financial Crisis. Scholars from diverse fields have conducted extensive and fruitful research on HCR within their own disciplines. This review suggests that the mainstream of pure quantitative research alone is insufficient to provide precise or comprehensive understanding of HCR. The complex relationships and interactions in HCR call for more integrative and cross-disciplinary research to more holistically understand complex and intricate HCRs. The complex nature of HCR requires deep qualitative exploration based on in-depth data to capture the everydayness of organizational activities and to register its individuality and variety. Despite previous efforts, a systematic and holistic integration of HCR research among multiple disciplines is lacking. Using a retrospective analysis of articles published in the field of economics, finance and management, including psychology, human resources management (HRM), organizational behaviour (OB), industrial and organizational psychology (I-O psychology), organizational theory, and strategy literatures, this study summaries and compares the major perspectives, theories, and findings on HCR research. A careful examination of the progress of the debates of HCR definitions and measurements in distinct disciplines enables an identification of the limitations and gaps in existing research. It enables an analysis of the interplay of these concepts, as well as that of the related concepts of intellectual capital, social capital, and Chinese guanxi, and how they provide a broader perspective on the HCR-related influences on firms’ competitive advantage. The study also introduces the themes of Environmental, Social and Governance, or ESG based investing, as the burgeoning body of ESG studies illustrates the rising importance of human and non-financial capital in investment process. The ESG literature locates HCR into a broader research context of the value of non-financial capital in explaining firm performance. The study concludes with a discussion of new directions for future research that may help advance our knowledge of HCR.

Keywords: human capital resources, social capital, Chinese guanxi, human resources management

Procedia PDF Downloads 359
170 Object-Scene: Deep Convolutional Representation for Scene Classification

Authors: Yanjun Chen, Chuanping Hu, Jie Shao, Lin Mei, Chongyang Zhang

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Traditional image classification is based on encoding scheme (e.g. Fisher Vector, Vector of Locally Aggregated Descriptor) with low-level image features (e.g. SIFT, HoG). Compared to these low-level local features, deep convolutional features obtained at the mid-level layer of convolutional neural networks (CNN) have richer information but lack of geometric invariance. For scene classification, there are scattered objects with different size, category, layout, number and so on. It is crucial to find the distinctive objects in scene as well as their co-occurrence relationship. In this paper, we propose a method to take advantage of both deep convolutional features and the traditional encoding scheme while taking object-centric and scene-centric information into consideration. First, to exploit the object-centric and scene-centric information, two CNNs that trained on ImageNet and Places dataset separately are used as the pre-trained models to extract deep convolutional features at multiple scales. This produces dense local activations. By analyzing the performance of different CNNs at multiple scales, it is found that each CNN works better in different scale ranges. A scale-wise CNN adaption is reasonable since objects in scene are at its own specific scale. Second, a fisher kernel is applied to aggregate a global representation at each scale and then to merge into a single vector by using a post-processing method called scale-wise normalization. The essence of Fisher Vector lies on the accumulation of the first and second order differences. Hence, the scale-wise normalization followed by average pooling would balance the influence of each scale since different amount of features are extracted. Third, the Fisher vector representation based on the deep convolutional features is followed by a linear Supported Vector Machine, which is a simple yet efficient way to classify the scene categories. Experimental results show that the scale-specific feature extraction and normalization with CNNs trained on object-centric and scene-centric datasets can boost the results from 74.03% up to 79.43% on MIT Indoor67 when only two scales are used (compared to results at single scale). The result is comparable to state-of-art performance which proves that the representation can be applied to other visual recognition tasks.

Keywords: deep convolutional features, Fisher Vector, multiple scales, scale-specific normalization

Procedia PDF Downloads 331
169 Followership Styles in the U.S. Hospitality Workforce: A Multi-Generational Comparison Study

Authors: Yinghua Huang, Tsu-Hong Yen

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The latest advance in leadership research has revealed that leadership is co-created through the combined action of leading and following. The role of followers is as important as leaders in the leadership process. However, the previous leadership studies often conceptualize leadership as a leader-centric process, while the role of followers is largely neglected in the literature. Until recently, followership studies receives more attention because the character and behavior of followers are as vital as the leader during the leadership process. Yet, there is a dearth of followership research in the context of tourism and hospitality industries. Therefore, this study seeks to fill in the gap of knowledge and investigate the followership styles in the U.S. hospitality workforce. In particular, the objectives of this study are to identify popular followership practices among hospitality employees and evaluate hospitality employees' followership styles using Kelley’s followership typology framework. This study also compared the generational differences in followership styles among hospitality employees. According to the U.S. Bureau of Labor Statistics, the workforce in the lodging and foodservice sectors consists of around 12% baby boomers, 29% Gen Xs, 23% Gen Ys, and 36% Gen Zs in 2019. The diversity of workforce demographics in the U.S. hospitality industry calls for more attention to understand the generational differences in followership styles and organizational performance. This study conducted an in-depth interview and a questionnaire survey to collect both qualitative and quantitative data. A snowball sampling method was used to recruit participants working in the hospitality industry in the San Francisco Bay Area, California, USA. A total of 120 hospitality employees participated in this study, including 22 baby boomers, 32 Gen Xs, 30 Gen Ys, and 36 Gen Zs. 45% of the participants were males, and 55% were female. The findings of this study identified good followership practices across the multi-generational participants. For example, a Gen Y participant said that 'followership involves learning and molding oneself after another person usually an expert in an area of interest. I think of followership as personal and professional development. I learn and get better by hands-on training and experience'. A Gen X participant said that 'I can excel by not being fearful of taking on unfamiliar tasks and accepting challenges.' Furthermore, this study identified five typologies of Kelley’s followership model among the participants: 45% exemplary followers, 13% pragmatist followers, 2% alienated followers, 18% passive followers, and 23% conformist followers. The generational differences in followership styles were also identified. The findings of this study contribute to the hospitality human resource literature by identifying the multi-generational perspectives of followership styles among hospitality employees. The findings provide valuable insights for hospitality leaders to understand their followers better. Hospitality leaders were suggested to adjust their leadership style and communication strategies based on employees' different followership styles.

Keywords: followership, hospitality workforce, generational diversity, Kelley’s followership topology

Procedia PDF Downloads 129
168 A Study on the Planning of Urban Road Traffic Signs Based on the Leisure Involvement of Self-Driving Tourists

Authors: Chun-Lin Zhang, Min Wan

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With the upgrade development of the tourism industry from the simple sightseeing tour to the leisure and vacation, people's travel idea has undergone a fundamental change. More and more people begin to pursue liberal and personal tourism, so self-driving tourism has become the main form of current tourism activities. With the self-driving tourism representing the general trend, the importance of convenient tourism transportation and perfect road traffic signs have become more and more prominent. A clear urban road traffic signs can help visitors quickly identify the direction and distance to the tourism destination. The purpose of this article is analyzing the planning of urban road traffic signs which can bring positive impact on the participation in the recreation involved of self-driving tourists. The content of this article is divided into three parts. Based on the literature review and theoretical analysis, the first part constructs a structural variance model. The model is from three dimensions: the attention of the self-driving tourists to the urban traffic signs along the road, the perception of the self-driving tourists to the road traffic signs itself, the perceptions of the self-driving tourists to the tourism destination information on the traffic signs. Through this model, the paper aims to explore the influence of the urban road traffic signs to the leisure psychological involvement and leisure behavior involvement of the self-driving tourists. The second part aims to verify through the hypothesis model the questionnaire survey and come to preliminary conclusions. The preliminary conclusions are as follows: firstly, the color, shape, size, setting mode and occurrence frequency of urban road traffic sign have significant influence on the leisure psychological involvement and leisure behavior involvement of the self-driving tourists. Secondly, the influence on the leisure behavior involvement is obviously higher than the influence on the leisure psychological involvement. Thirdly, the information about the tourism destination marked on the urban road traffic signs has not obviously influence on the leisure psychological involvement, but it has distinct influence on the leisure behavior involvement of self-driving tourists. The third part puts forward that the planning of urban road traffic signs should focus on the angle of the impact of road traffic signs on people's psychology and behavior. On the basis of the above conclusions, the paper researches the color, shape, size, setting mode and information labeling of urban road traffic signs so that they can preferably satisfy the demand of the leisure involvement of self-driving tourists.

Keywords: leisure involvement, self-driving tourism, structural equation, urban road traffic signs

Procedia PDF Downloads 237
167 Robust Processing of Antenna Array Signals under Local Scattering Environments

Authors: Ju-Hong Lee, Ching-Wei Liao

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An adaptive array beamformer is designed for automatically preserving the desired signals while cancelling interference and noise. Providing robustness against model mismatches and tracking possible environment changes calls for robust adaptive beamforming techniques. The design criterion yields the well-known generalized sidelobe canceller (GSC) beamformer. In practice, the knowledge of the desired steering vector can be imprecise, which often occurs due to estimation errors in the DOA of the desired signal or imperfect array calibration. In these situations, the SOI is considered as interference, and the performance of the GSC beamformer is known to degrade. This undesired behavior results in a reduction of the array output signal-to-interference plus-noise-ratio (SINR). Therefore, it is worth developing robust techniques to deal with the problem due to local scattering environments. As to the implementation of adaptive beamforming, the required computational complexity is enormous when the array beamformer is equipped with massive antenna array sensors. To alleviate this difficulty, a generalized sidelobe canceller (GSC) with partially adaptivity for less adaptive degrees of freedom and faster adaptive response has been proposed in the literature. Unfortunately, it has been shown that the conventional GSC-based adaptive beamformers are usually very sensitive to the mismatch problems due to local scattering situations. In this paper, we present an effective GSC-based beamformer against the mismatch problems mentioned above. The proposed GSC-based array beamformer adaptively estimates the actual direction of the desired signal by using the presumed steering vector and the received array data snapshots. We utilize the predefined steering vector and a presumed angle tolerance range to carry out the required estimation for obtaining an appropriate steering vector. A matrix associated with the direction vector of signal sources is first created. Then projection matrices related to the matrix are generated and are utilized to iteratively estimate the actual direction vector of the desired signal. As a result, the quiescent weight vector and the required signal blocking matrix required for performing adaptive beamforming can be easily found. By utilizing the proposed GSC-based beamformer, we find that the performance degradation due to the considered local scattering environments can be effectively mitigated. To further enhance the beamforming performance, a signal subspace projection matrix is also introduced into the proposed GSC-based beamformer. Several computer simulation examples show that the proposed GSC-based beamformer outperforms the existing robust techniques.

Keywords: adaptive antenna beamforming, local scattering, signal blocking, steering mismatch

Procedia PDF Downloads 112
166 Air Quality Health Index in Windsor, Canada, and the Impact of Regional Scale Transport

Authors: Xiaohong Xu, Tianchu Zhang, Yangfan Chen, Rongtai Tan

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In Canada, Air Quality Health Index (AQHI) is a scale designed to help residences understand the impact of air quality on human health. In Ontario, Canada, AQHI was implemented in June 2015. This study investigated temporal variability of daily AQHI and impact of regional transport on AQHI in Windsor, Ontario, Canada from 2016 to 2019. During 2016–2019, 1428 daily AQHIs were recorded in Windsor Downtown Station. Among those, the AQHIs were at the low health risk level (AQHI = 1, 2 or 3) in 82% of days, only a few days at high risk level (AQHI = 7), the rest were at moderate health risk level (AQHI = 4, 5, 6), indicating air quality in Windsor was fairly good with relatively low health risk. The annual mean AQHI value decreased from 2.95 in 2016 to 2.81 in 2019, demonstrating the improvement of air quality. Half of the days, AQHI were 3 regardless of season. AQHI was higher in the warm season (3.1) than in the cold season (2.6) due to more frequent moderate risk days (27%, AQHI = 4) in warm season and more frequent low risk days (42%, AQHI = 2) in the cold season. Among the three pollutants considered in AQHI calculation, O3 was the most frequently reported dominant contributor to daily AQHI (88% of days), followed by NO2 (12%), especially in the cold season, with small contribution from PM2.5 (<1%). In the past two decades, NO2 concentrations had decreased significantly and O3 concentrations had increased, resulting in daily AQHI being less reliance on NO2 (from 51% of days being the primary contributor during 2003–2010 to 12% during 2016–2019) and more on O3 concentrations (49% to 88%). Trajectory analysis found that AQHI ≤ 3 days were closely associated with air masses from the north and northwest, whereas AQHI > 3 days were closely associated with air masses from the west and southwest. This is because northerly flows brought in clear air mass owing to less industrial facilities, while polluted air masses were transported from the south of Windsor, where several industrial states of the US were located. Overall, O3 concentrations dictate the daily AQHI values, the seasonal variability of AQHI, and the impact of regional transport on AQHI in Windsor. This makes further reductions of AQHI challenging because O3 concentrations are likely to continue increasing due to weakened consumption of O3 by NO owing to decreasing NO emissions and more hot days because of climate change. The predominant and increasing contribution of O3 to AQHI calls for more effective control measures to mitigate O3 pollution and its impact on human health and the environment.

Keywords: air quality, Air Quality Health Index (AQHI), hysplit, regional transport, windsor

Procedia PDF Downloads 64
165 Effect of Ease of Doing Business to Economic Growth among Selected Countries in Asia

Authors: Teodorica G. Ani

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Economic activity requires an encouraging regulatory environment and effective rules that are transparent and accessible to all. The World Bank has been publishing the annual Doing Business reports since 2004 to investigate the scope and manner of regulations that enhance business activity and those that constrain it. A streamlined business environment supporting the development of competitive small and medium enterprises (SMEs) may expand employment opportunities and improve the living conditions of low income households. Asia has emerged as one of the most attractive markets in the world. Economies in East Asia and the Pacific were among the most active in making it easier for local firms to do business. The study aimed to describe the ease of doing business and its effect to economic growth among selected economies in Asia for the year 2014. The study covered 29 economies in East Asia, Southeast Asia, South Asia and Middle Asia. Ease of doing business is measured by the Doing Business indicators (DBI) of the World Bank. The indicators cover ten aspects of the ease of doing business such as starting a business, dealing with construction permits, getting electricity, registering property, getting credit, protecting investors, paying taxes, trading across borders, enforcing contracts and resolving insolvency. In the study, Gross Domestic Product (GDP) was used as the proxy variable for economic growth. Descriptive research was the research design used. Graphical analysis was used to describe the income and doing business among selected economies. In addition, multiple regression was used to determine the effect of doing business to economic growth. The study presented the income among selected economies. The graph showed China has the highest income while Maldives produces the lowest and that observation were supported by gathered literatures. The study also presented the status of the ten indicators of doing business among selected economies. The graphs showed varying trends on how easy to start a business, deal with construction permits and to register property. Starting a business is easiest in Singapore followed by Hong Kong. The study found out that the variations in ease of doing business is explained by starting a business, dealing with construction permits and registering property. Moreover, an explanation of the regression result implies that a day increase in the average number of days it takes to complete a procedure will decrease the value of GDP in general. The research proposed inputs to policy which may increase the awareness of local government units of different economies on the simplification of the policies of the different components used in measuring doing business.

Keywords: doing business, economic growth, gross domestic product, Asia

Procedia PDF Downloads 379
164 Effect of Laser Ablation OTR Films on the Storability of Handaeri – gomchwi (Ligularia fischeri var. spiciformis Nakai) Jangajji in MA (Modified Atmosphere) Storage

Authors: In-Lee Choi, Sung Mi Hong, Min Jae Jeong, Jun Pill Baek, Ho-Min Kang

Abstract:

Gomchwi (Ligularia fischeri) is grown in the wetland of the deep mountains in Korea and East Asia and has properties that are, inflammation control, whitening, antimutagenic and antigenotoxic. Jangajji is a type of pickle in Korean fermented food which is made by pickling or marinating vegetables in a sauce, such as soy sauce, chili pepper paste, soybean paste, or diluted vinegar for a long period of time. Handaeri-gomchwi jangajii is generally packed a film that has very low or no gas permeability in the Korean domestic market, so packages have a risk of swelling or bursting as a result of internal gas generation during storage or sale This study was conducted to improve secure distribution of Handaeri-gomchwi (Ligularia fischeri var. spiciformis Nakai) Jangajji using laser ablation OTR (oxygen transmission rate) films. Handaeri-gomchwi cultivated in Yangu, Gangwon province, Republic of Korea (Ligularia fischeri var. spiciformis Nakai) was processed in to Jangajji using soy sauce. They were packed by different OTR films, and were stored for 90 days in 7℃(10,000 cc, 20,000 cc, 40,000 cc and 80,000 cc O2/m²• day • atm), 20 days in 20℃ (10,000 cc, 30,000 cc, 70,000 cc and 100,000 cc) and compared with the control film(PP film, 1,300cc). The fresh weight loss, carbon dioxide, oxygen, and ethylene concentrations of Handaeri–gomchwi packages were measured during storage. On the final day of storage, incidence rate of fungi, pH, salinity, firmness, and off-flavor were measured. The fresh weight loss rate of Handaeri–gomchwi was less than 2.0% in 10,000cc OTR films at two different storage periods and temperatures. At 80,000cc(7℃) and 100,000cc(20℃), carbon dioxide contents were 2.0% and 6.4% respectively, whereas the control treatment had the highest concentration. Which was 35%(20℃) and 15%(7℃) , that resulted the packages to swell during storage. The control treatment Showed the lowest oxygen concentration at 2.5% in 7℃ and 0.8% in 20℃. Packages in 7℃ (0.3-1.7μL/L) showed very lower ethylene concentration than in 20℃(10-25μL/L), they also had no significant relation. On the final storage day, fungi were found in every film at both temperatures, except the 10,000cc, as oxygen permeability increased so did the pH, while the salinity decreased. Firmness and off-flavor Showed the best results at 10,000cc in both temperatures best result at 10,000cc in both temperature. Following the results, 10,000cc film is the most reasonable treat in storing Handaeri–gomchwi. For it had a suitable oxygen transmission rate, which prevents billowing, and maintained good qualities in both temperatures.

Keywords: carbon dioxide, Korean pickle, marketable, oxygen

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