Search results for: Yong Bo Shao

Authors: Fangyuan Shao, Wei Liu, Deli Gao

Abstract:

Polycrystalline diamond compact (PDC) bits have occupied a large market of unconventional oil and gas drilling. The application of PDC bits benefits from the efficient rock breaking of PDC cutters. In response to increasingly complex formations, many shaped cutters have been invited, but many of them have not been solved by the mechanism of rock breaking. In this paper, two kinds of PDC cutters: a new axe-shaped (NAS) cutter and cylindrical cutter (benchmark) were studied by laboratory experiments. NAS cutter is obtained by optimizing two sides of axe-shaped cutter with curved surfaces. All the cutters were put on a vertical turret lathe (VTL) in the laboratory for cutting tests. According to the cutting distance, the VTL tests can be divided into two modes: single-turn rotary cutting and continuous cutting. The cutting depth of cutting (DOC) was set at 1.0 mm and 2.0 mm in the former mode. The later mode includes a dry VTL test for thermal stability and a wet VTL test for wear resistance. Load cell and 3D optical profiler were used to obtain the value of cutting forces and wear area, respectively. Based on the findings of the single-turn rotary cutting VTL tests, the performance of A NAS cutter was better than the benchmark cutter on elastoplastic material cutting. The cutting forces (normal forces, tangential force, and radial force) and special mechanical energy (MSE) of a NAS cutter were lower than that of the benchmark cutter under the same condition. It meant that a NAS cutter was more efficient on elastoplastic material breaking. However, the wear resistance of a new axe-shaped cutter was higher than that of a benchmark cutter. The results of the dry VTL test showed that the thermal stability of a NAS cutter was higher than that of a benchmark cutter. The cutting efficiency can be improved by optimizing the geometric structure of the PDC cutter. The change of thermal stability may be caused by the decrease of the contact area between cutter and rock at given DOC. The conclusions of this paper can be used as an important reference for PDC cutters designers.

Keywords: axe-shaped cutter, PDC cutter, rotary cutting test, vertical turret lathe

Procedia PDF Downloads 187

Authors: Young-Ok Yoon, Su-Yeon Lee, Seong-Ho Ha, Gil-Yong Yeom, Bong-Hwan Kim, Hyun-Kyu Lim, Shae K. Kim

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Al-7Si-0.4Mg alloy (designated A356) is widely used in the automotive and aerospace industries as structural components due to an excellent combination of castability and mechanical properties. Grain refinement has a significant effect on the mechanical properties of castings, mainly since the distribution of secondary phase is changed. As a grain refiner, the Al-Ti-B master alloys containing TiAl3 and TiB2 particles have been widely used in Al foundries. The Mg loss and Mg based inclusion formation by the strong affinity of Mg to oxygen in the melting process of Mg contained alloys have been an issue. This can be significantly improved only by Mg+Al2Ca master alloy as an alloying element instead of pure Mg. Moreover, the eutectic Si modification and grain refinement is simultaneously obtained because Al2Ca behaves as Ca, a typical Si modifier. The present study is focused on the combined effects of Mg+Al2Ca and Al-Ti-B master alloys on the grain refiment of Al-7Si-0.4Mg alloy and their proper ratio for the optimum effect. The aim of this study, therefore, is to investigate the change of the microstructure in Al-7Si-0.4Mg alloy with different ratios of Ti and Al2Ca (detected Ca content) and their effects on the tensile property. The distribution and morphology of the secondary phases by the grain refinement will be discussed.

Keywords: Al-7Si-0.4Mg alloy, Al2Ca, Al-Ti-B alloy, grain refinement

Procedia PDF Downloads 415

Authors: Kyung Min Kang, Peng Mou, Dong Xiang, Yong Yang, Gang Shen

Abstract:

In this paper, planet pin parallelism error, which is one of manufacturing error of planet carrier, is employed as a main variable to influence planet load sharing factor. This error is categorize two group: (i) pin parallelism error with rotation on the axis perpendicular to the tangent of base circle of gear(x axis rotation in this paper) (ii) pin parallelism error with rotation on the tangent axis of base circle of gear(y axis rotation in this paper). For this study, the planetary gear system in 1.5MW wind turbine is applied and pure torsional rigid body model of this planetary gear is built using Solidworks and MSC.ADAMS. Based on quantified parallelism error and simulation model, dynamics simulation of planetary gear is carried out to obtain dynamic mesh load results with each type of error and load sharing factor is calculated with mesh load results. Load sharing factor formula and the suggestion for planetary reliability design is proposed with the conclusion of this study.

Keywords: planetary gears, planet load sharing, MSC. ADAMS, parallelism error

Procedia PDF Downloads 386

Authors: Xuling Zhang, Yong Wang, Xingyun Liu, Shuangxue Xu

Abstract:

Based on positive psychology, this study presented a mediated moderation model in which character strengths moderated the relationship between interpersonal relationship, job satisfaction and subjective well-being, with job satisfaction taking the mediation role among them. A total of 912 teachers participated in four surveys, which include the Oxford Happiness Questionnaire, Values in Action Inventory of Strengths, job satisfaction questionnaire, and the interpersonal relationship questionnaire. The results indicated that: (1) Taking interpersonal relationship as a typical work environmental variable, the result shows that it is significantly correlated to subjective well-being. (2) The character strengths of "kindness", “authenticity” moderated the effect of the teachers’ interpersonal relationship on subjective well-being. (3) The teachers’ job satisfaction mediated the above mentioned moderation effects. In general, this study shows that the teachers’ interpersonal relationship affects their subjective well-being, with their job satisfaction as mediation and character strengths of “kindness” and “authenticity” as moderation. The managerial implications were also discussed.

Keywords: character strength, subjective well-being, job satisfaction, interpersonal relationship

Procedia PDF Downloads 287

Authors: Yiling Shao, Megan Dai

Abstract:

This paper attempts to explore whether the cultural infrastructure supported by the Chinese government is still subject to a logic of “strict regulation”.Previous studies have pointed out that the "paternalism" tendency of China's cultural policy always leads to excessive government intervention in cultural development, while Chinese cultural practitioners can only seek cultural autonomy in the cracks of supervision. This can also explain why Chinese cultural policies sometimes have different effects than the official expectations.But this only reflects one aspect of China's cultural policy. In fact, the welfare cultural infrastructure funded by the government seems to highlight the principles of "safeguarding citizens' cultural rights" and "citizens' voluntary" rather than "indoctrination" and "enlightenment", What new features of China's cultural policy are reflected behind this policy orientation that is completely different from the logic of "regulation", which has also become an important issue in this paper. Based on the field survey of a cultural infrastructure (Gao ming District Cultural Center) in Gao ming District, Fo shan City, Guangdong Province, China, for nearly one year, the authors have obtained many text and picture materials.The paper discusses the dual role of cultural centers in China's cultural policy -both as a formal commitment by the state to protect citizens' basic cultural rights and as a social space for citizens to use preferential policies to obtain cultural capital. All in all, the author have conclued three operational logics of the cultural infrastructure currently supported by the Chinese government (at least in developed areas): first, the cultural center has become a versatile cultural space; second, grass-roots cultural cadres can be described as "policy entrepreneurs"; third, ordinary citizens will use the officially supported cultural infrastructure to increase cultural capital. This paper argues that, in comparison to the common “regulatory hand” in the field of cultural industries, in cultural infrastructure supported by state, the authorities and citizens are not in conflict. On the contrary, authorities must adopt a de-regulatory "pleasing" strategy to gain the support of citizens.

Keywords: cultural infrastructure, cultural capital, deregulation, policy entrepreneur

Procedia PDF Downloads 79

Authors: Xin Li, Yan-Rong Guo, Jin-Fang Lin, Yi Feng, Håkan Billig, Ruijin Shao

Abstract:

Background: Young women with polycystic ovary syndrome (PCOS) have a high risk of developing endometrial carcinoma. There is a need for the development of new medical therapies that can reduce the need for surgical intervention so as to preserve the fertility of these patients. The aim of the study was to describe and discuss cases of PCOS and insulin resistance (IR) women with early endometrial carcinoma while being co-treated with Diane-35 and metformin. Methods: Five PCOS-IR women who were scheduled for diagnosis and therapy for early endometrial carcinoma were recruited. The hospital records and endometrial pathology reports were reviewed. All patients were co-treated with Diane-35 and metformin for 6 months to reverse the endometrial carcinoma and preserve their fertility. Before, during, and after treatment, endometrial biopsies and blood samples were obtained and oral glucose tolerance tests were performed. Endometrial pathology was evaluated. Body weight (BW), body mass index (BMI), follicle-stimulating hormone (FSH), luteinizing hormone (LH), total testosterone (TT), sex hormone-binding globulin (SHBG), free androgen index (FAI), insulin area under curve (IAUC), and homeostasis model assessment of insulin resistance (HOMA-IR) were determined. Results: Clinical stage 1a, low grade endometrial carcinoma was confirmed before treatment. After 6 months of co-treatment, all patients showed normal epithelia. No evidence of atypical hyperplasia or endometrial carcinoma was found. Co-treatment resulted in significant decreases in BW, BMI, TT, FAI, IAUC, and HOMA-IR in parallel with a significant increase in SHBG. There were no differences in the FSH and LH levels after co-treatment. Conclusions: Combined treatment with Diane-35 and metformin has the potential to revert the endometrial carcinoma into normal endometrial cells in PCOS-IR women. The cellular and molecular mechanisms behind this effect merit further investigation.

Keywords: PCOS, progesterone resistance, insulin resistance, steroid hormone receptors, endometrial carcinoma

Procedia PDF Downloads 390

Authors: Yong-Heng Shi, Peng Hao, Bai-Chen Xie

Abstract:

Solar prosumers are playing increasingly prominent roles in the power system. However, its uncertainty affects the outcomes and functions of the power market, especially in the asymmetric information environment. Therefore, an important issue is how to take effective measures to reduce the impact of uncertainty on market equilibrium. We propose a two-level stochastic differential game model to explore the Cournot decision problem of prosumers. In particular, we study the impact of punishment and cooperation mechanisms on the efficiency of the Cournot game in which prosumers face uncertainty. The results show that under the penalty mechanism of fixed and variable rates, producers and consumers tend to take conservative actions to hedge risks, and the variable rates mechanism is more reasonable. Compared with non-cooperative situations, prosumers can improve the efficiency of the game through cooperation, which we attribute to the superposition of market power and uncertainty reduction. In addition, the market environment of asymmetric information intensifies the role of uncertainty. It reduces social welfare but increases the income of prosumers. For regulators, promoting alliances is an effective measure to realize the integration, optimization, and stable grid connection of producers and consumers.

Keywords: Cournot games, power market, uncertainty, prosumer cooperation

Procedia PDF Downloads 89

Authors: Hyun-Koo Kim, Yong-Hun Kim, Soo-Young Suk, Ju H. Park, Ho-Youl Jung

Abstract:

This paper presents an effective speed hump detection process at the day-time. we focus only on round types of speed humps in the day-time dynamic road environment. The proposed speed hump detection scheme consists mainly of two process as stereo matching and speed hump detection process. Our proposed process focuses to speed hump detection process. Speed hump detection process consist of noise reduction step, data fusion step, and speed hemp detection step. The proposed system is tested on Intel Core CPU with 2.80 GHz and 4 GB RAM tested in the urban road environments. The frame rate of test videos is 30 frames per second and the size of each frame of grabbed image sequences is 1280 pixels by 670 pixels. Using object-marked sequences acquired with an on-vehicle camera, we recorded speed humps and non-speed humps samples. Result of the tests, our proposed method can be applied in real-time systems by computation time is 13 ms. For instance; our proposed method reaches 96.1 %.

Keywords: data fusion, round types speed hump, speed hump detection, surface filter

Procedia PDF Downloads 495

Authors: Pui Yong Leo, Normy Maziah Mohd Said

Abstract:

Change of global economy landscape and business environment has led to companies’ decision to go global and enter international markets. As the companies go beyond the comfort zone (i.e. investing in the home country), it is important to ensure a comprehensive risk assessment is carried out. This paper describes a standardized approach for international investment, ensuring identification of risk, risk appetite, risk rating, risk treatment and mitigation plans for respective international investment proposal. The standardized approach is divided into three (3) stages as follows: Stage 1 – Preliminary Risk profiling; with the objective to gauge exposure to countries and high level risk factors as first level assessment. Stage 2 – Risk Parameters; with the objective to define risk appetite for the international investment from the perspective of likelihood and impact. Stage 3 – Detailed Risk Assessments; with the objectives to assess in detail any triggered elements from Stage 1, and project specific risks. The final output will include the mitigation plans for the identified risks for the total investment. Example will be given in this paper to show how comprehensive risk assessment is carried out for an international investment in power energy sector.

Keywords: international investment, mitigation plans, risk appetite, risk assessment

Procedia PDF Downloads 362

Authors: Thamo Sutharssan, Diogo Montalvao, Wen-Chung Wang, Yong Chen, Claudia Pisac

Abstract:

A combined heat and power (CHP) system is an efficient and clean way to generate power (electricity). Heat produced by the CHP system can be used for water and space heating. The CHP system which uses hydrogen as fuel produces zero carbon emission. Its’ efficiency can reach more than 80% whereas that of a traditional power station can only reach up to 50% because much of the thermal energy is wasted. The other advantages of CHP systems include that they can decentralize energy generation, improve energy security and sustainability, and significantly reduce the energy cost to the users. This paper presents the economic benefits of using a CHP system in the domestic environment. For this analysis, natural gas is considered as potential fuel as the hydrogen fuel cell based CHP systems are rarely used. UK government incentives for CHP systems are also considered as the added benefit. Results show that CHP requires a significant initial investment in return it can reduce the annual energy bill significantly. Results show that an investment may be paid back in 7 years. After the back period, CHP can run for about 3 years as most of the CHP manufacturers provide 10-year warranty.

Keywords: combined heat and power, clean energy, hydrogen fuel cell, economic analysis of CHP, zero emission

Procedia PDF Downloads 368

Authors: Choi Duckkyu, Choi Yong, Kang Taegyoung, Jun Hyeonjong, Choi Ilsu, Hyun Changsik

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This study was carried out to develop a soybean combine thresher that enables to reduce the damage rate of soybean threshing and the rate of unthreshing. The combine threshing cylinder was developed with 6 circular axis at each end and fixed with disc plates. It was attached to the prototype combine thresher. A combine thresher that has a cylinder with circular rod type threshing pegs was used for a comparative test. A series of comparative tests were conducted using dae-won soybean. The test of the soybean thresher was performed at the cylinder speeds of 210, 240, 270 and 300 rpm, and with the concave clearance of 10, 13 and 16 mm. The separating positions of soybean after threshing were researched on a separate box with 4 sections. The soybean positions of front, center, rear and rear outside, of 59.5%, 30.6%, 7.8% and 2.2% respectively, were obtained. At the cylinder speeds from 210 rpm to 300 rpm, the damage rate of soybean was increased from 0.1% to 4.2% correspondingly to speeds. The unthreshed rate of soybean under the same condition was increased from 0.9% to 4.1% correspondingly to speeds. 0.7% of the damage rate and 1.5% of the unthreshed rate was achieved at the cylinder speed of 240 rpm and with the concave clearance of 10 mm. For Daewon soybean, an optimum cylinder speed of 240 rpm and the concave clearance of 10 mm were identified. These results will be useful for the design, construction, and operation of soybean threshing harvesters.

Keywords: soybean harvest, combine threshing, threshing cylinder, optimum design

Procedia PDF Downloads 509

Authors: Ayliana Dharmawan, Heng Yong Sheng, Zhang Xiaojin, Tan Thai Lian

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To facilitate discharge planning, doctors are presently required to assign an Estimated Discharge Date (EDD) for each patient admitted to the hospital. This assignment of the EDD is largely based on the doctor’s judgment. This can be difficult for cases which are complex or relatively new to the doctor. It is hypothesized that a data-driven approach would be able to facilitate the doctors to make accurate estimations of the discharge date. Making use of routinely collected data on inpatient discharges between January 2013 and May 2016, a predictive model was developed using machine learning techniques to predict the Length of Stay (and hence the EDD) of inpatients, at the point of admission. The predictive performance of the model was compared to that of the clinicians using accuracy measures. Overall, the best performing model was found to be able to predict EDD with an accuracy improvement in Average Squared Error (ASE) by -38% as compared to the first EDD determined by the present method. It was found that important predictors of the EDD include the provisional diagnosis code, patient’s age, attending doctor at admission, medical specialty at admission, accommodation type, and the mean length of stay of the patient in the past year. The predictive model can be used as a tool to accurately predict the EDD.

Keywords: inpatient, estimated discharge date, EDD, prediction, data-driven

Procedia PDF Downloads 153

Authors: Ju Yeon Lee, Seol Ah Oh, Hong il Kim, Hae Yong Do, Sung Won Choi

Abstract:

The purpose of this study was to develop a Well-being and Moments Scale (WAMS) for evaluating the efficacy of ‘vacationing’ as a form of mental health recuperation. ‘Vacationing’ is defined as a going outside one’s usual environment to seek refreshment and relief from one’s daily life. To develop WAMS, we followed recommended procedures for scale development, including reviewing related studies, conducting focus group interviews to elucidate the need for this assessment area, and modifying items based on expert opinion. Through this process, we developed the WAMS. The psychometric properties of the WAMS were then tested in two separate samples. Exploratory factor analysis (EFA) was conducted using 1.41 participants (mean age = 30.45 years; range: 20-50 years) to identify the underlying 3-factor structure of 'Positive Emotions', 'Life Satisfaction' and 'Self-Confidence.' The 26 items retained based on the EFA procedures were associated with excellent reliability (i.e., α = 0.93). Confirmatory factor analysis was then conducted using 200 different participants (mean age = 29.51 years; range: 20-50 years) and revealed good model fit for our hypothesized 3-factor model. Convergent validity tests also revealed correlations with other scales in the expected direction and range. Study limitations as well as the importance and utility of WMAS are also discussed.

Keywords: vacationing, positive affect, life satisfaction, self-confidence, WAMS

Procedia PDF Downloads 321

Authors: Khizir Mohd Ismail, Yu Jun Lim, Tshun Howe Yong

Abstract:

The study of flow behavior in an enclosed volume using Computational Fluid Dynamics (CFD) has been around for decades. However, due to the knowledge limitation of adaptive grid methods, the flow in an enclosed volume near the moving wall using CFD is less explored. A CFD simulation of flow in an enclosed volume near a moving wall was demonstrated and studied by introducing a moving mesh method and was modeled with Unsteady Reynolds-Averaged Navier-Stokes (URANS) approach. A static enclosed volume with controlled opening size in the bottom was positioned against a moving, translational wall with sliding mesh features. Controlled variables such as smoothed, crevices and corrugated wall characteristics, the distance between the enclosed volume to the wall and the moving wall speed against the enclosed chamber were varied to understand how the flow behaves and reacts in between these two geometries. These model simulations were validated against experimental results and provided result confidence when the simulation had shown good agreement with the experimental data. This study had provided better insight into the flow behaving in an enclosed volume when various wall types in motion were introduced within the various distance between each other and create a potential opportunity of application which involves adaptive grid methods in CFD.

Keywords: moving wall, adaptive grid methods, CFD, moving mesh method

Procedia PDF Downloads 128

Authors: K. Abdul Halim, E. L. Yong

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Palm oil industry is a major revenue earner in Malaysia, despite the growth of the industry is synonymous with a massive production of agro-industrial wastewater. Through the oil extraction processes, palm oil mill effluent (POME) contributes to the largest liquid wastes generated. Due to the high amount of organic compound, POME can cause inland water pollution if discharged untreated into the water course as well as affect the aquatic ecosystem. For more than 20 years, Malaysia adopted the conventional biological treatment known as lagoon system that apply biological treatment. Besides having difficulties in complying with the standard, a large build up area is needed and retention time is higher. Although anaerobic digester is more favorable, this process comes along with enormous volumes of sludge and methane gas, demanding attention from the mill operators. In order to reduce the sludge production, denitrifiers are to be removed first. Sulfate reducing bacteria has shown the capability to inhibit the growth of methanogens. This is expected to substantially reduce both the sludge and methane production in anaerobic digesters. In this paper, the effectiveness of sulfate reducing bacteria in minimizing sludge and methane will be examined.

Keywords: methane reduction, palm oil mill effluent, sludge minimization, sulfate reducing bacteria, sulfate reduction

Procedia PDF Downloads 417

Authors: Jui-Pui Hung, Yong-Run Chen, Wei-Cheng Shih, Shen-He Tsui, Kung-Da Wu

Abstract:

This paper presents the effect on the tooling conditions on the machining stabilities of a milling machine tool. The machining stability was evaluated in different feeding direction in the X-Y plane, which was referred as the orientation-dependent machining stability. According to the machining mechanics, the machining stability was determined by the frequency response function of the cutter. Thus, we first conducted the vibration tests on the spindle tool of the milling machine to assess the tool tip frequency response functions along the principal direction of the machine tool. Then, basing on the orientation dependent stability analysis model proposed in this study, we evaluated the variation of the dynamic characteristics of the spindle tool and the corresponding machining stabilities at a specific feeding direction. Current results demonstrate that the stability boundaries and limited axial cutting depth of a specific cutter were affected to vary when it was fixed in the tool holder with different overhang length. The flute of the cutter also affects the stability boundary. When a two flute cutter was used, the critical cutting depth can be increased by 47 % as compared with the four flute cutter. The results presented in study provide valuable references for the selection of the tooling conditions for achieving high milling performance.

Keywords: tooling condition, machining stability, milling machine, chatter

Procedia PDF Downloads 416

Authors: Zixian Zhang, Shanliang Yao, Zile Huang, Zhaodong Wu, Xiaohui Zhu, Yong Yue, Jieming Ma

Abstract:

Unmanned Surface Vehicles (USVs) are valuable due to their ability to perform dangerous and time-consuming tasks on the water. Object detection tasks are significant in these applications. However, inherent challenges, such as the complex distribution of obstacles, reflections from shore structures, water surface fog, etc., hinder the performance of object detection of USVs. To address these problems, this paper provides a fusion method for USVs to effectively detect objects in the inland surface environment, utilizing vision sensors and 3+1D Millimeter-wave radar. MMW radar is complementary to vision sensors, providing robust environmental information. The radar 3D point cloud is transferred to 2D radar pseudo image to unify radar and vision information format by utilizing the point transformer. We propose a multi-source object detection network (RV-YOLOX )based on radar-vision fusion for inland waterways environment. The performance is evaluated on our self-recording waterways dataset. Compared with the YOLOX network, our fusion network significantly improves detection accuracy, especially for objects with bad light conditions.

Keywords: inland waterways, YOLO, sensor fusion, self-attention

Procedia PDF Downloads 75

Authors: Santiranjan Shannigrahi, Mohit Sharma, Ivan Tan Chee Kiang, Yong Anna Marie

Abstract:

Polymer-ceramics composites are gaining importance due to their high specific strength, corrosion resistance, and high mechanical properties, as well as low cost. As a result, polymer composites are suitable for various industrial applications, like automobiles, aerospace, and biomedical areas. The present work comprises the development of polymer-ceramic composite films and is tested for the harsh environment including weatherability and UV barrier property. The polymer composite films are kept in weather chamber for a fixed period of time followed by tested for their physical, mechanical and chemical properties. The composite films are fabricated using compounding followed by hot pressing. UV-visible spectroscopy results reveal that the pure polymer polyethylene (PE) films are transparent in the visible range and do not absorb UV. However, polymer ceramic composite films start absorbing UV completely even at very low filler loading amount of 5 wt.%. The changes in tensile properties of the various composite films before and after UV illuminations for 40 hrs at 60 degC are analyzed. The tensile strength of neat PE film has been observed 8% reduction, whereas the remarkable increase in tensile strength has been observed (18% improvement for 10 wt. % filled composites films). The UV exposure leads to strengthen the crosslinking among PE polymer chains in the filled composite films, which contributes towards the incremented tensile strength properties.

Keywords: polymer ceramic composite, processing, harsh environment, mechanical properties

Procedia PDF Downloads 367

Authors: Hyeon-Kyo Lim, Tong-il Jang, Yong-Hee Lee

Abstract:

As for any nuclear power plant, human error is one of the most dreaded factors that may result in unexpected accidents. Thus, for accident prevention, it is quite indispensable to analyze and to manage the influence of any factor which may raise the possibility of human errors. Among lots factors, stress has been reported to have significant influence on human performance. Stress level of a person may fluctuate over time. To handle the possibility over time, robust stress management program is required, especially in nuclear power plants. Therefore, to overcome the possibility of human errors, this study aimed to develop a stress management program as a part of Fitness-for-Duty (FFD) Program for the workers in nuclear power plants. The meaning of FFD might be somewhat different by research objectives, appropriate definition of FFD was accomplished in this study with special reference to human error prevention, and diverse stress factors were elicited for management of human error susceptibility. In addition, with consideration of conventional FFD management programs, appropriate tests and interventions were introduced over the whole employment cycle including selection and screening of workers, job allocation, job rotation, and disemployment as well as Employee-Assistance-Program (EAP). The results showed that most tools mainly concentrated their weights on common organizational factors such as Demands, Supports, and Relationships in sequence, which were referred as major stress factors.

Keywords: human error, accident prevention, work performance, stress, fatigue

Procedia PDF Downloads 316

Authors: Adam L. Yanagihara, Yong Seok Park

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The goal of this paper is to converge upon a design of a brake system that could be used for a roller coaster found at an amusement park. It was necessary to find what could be deemed as a “comfortable” deceleration so that passengers do not feel as if they are suddenly jerked and pressed against the restraining harnesses. A human factors engineering approach was taken in order to determine this deceleration. Using a previous study that tested the deceleration of transit vehicles, it was found that a -0.45 G deceleration would be used as a design requirement to build this system around. An adjustable linear eddy current brake using permanent magnets would be the ideal system to use in order to meet this design requirement. Anthropometric data were then used to determine a realistic weight and length of the roller coaster that the brake was being designed for. The weight and length data were then factored into magnetic brake force equations. These equations were used to determine how the brake system and the brake run layout would be designed. A final design for the brake was determined and it was found that a total of 12 brakes would be needed with a maximum braking distance of 53.6 m in order to stop a roller coaster travelling at its top speed and loaded to maximum capacity. This design is derived from theoretical calculations, but is within the realm of feasibility.

Keywords: eddy current brake, engineering design, design synthesis, human factors engineering

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Authors: Zhenzhen Xu, Chunfu Shao, Shengyou Wang, Chunjiao Dong

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To improve the satisfaction of residents' travel, this paper analyzes the characteristics and influencing factors of urban residents' travel behavior. First, a Multinominal Logit Model (MNL) model is built to analyze the characteristics of residents' travel behavior, reveal the influence of individual attributes, family attributes and travel characteristics on the choice of travel mode, and identify the significant factors. Then put forward suggestions for policy improvement. Finally, Support Vector Machine (SVM) and Multi-Layer Perceptron (MLP) models are introduced to evaluate the policy effect. This paper selects Futian Street in Futian District, Shenzhen City for investigation and research. The results show that gender, age, education, income, number of cars owned, travel purpose, departure time, journey time, travel distance and times all have a significant influence on residents' choice of travel mode. Based on the above results, two policy improvement suggestions are put forward from reducing public transportation and non-motor vehicle travel time, and the policy effect is evaluated. Before the evaluation, the prediction effect of MNL, SVM and MLP models was evaluated. After parameter optimization, it was found that the prediction accuracy of the three models was 72.80%, 71.42%, and 76.42%, respectively. The MLP model with the highest prediction accuracy was selected to evaluate the effect of policy improvement. The results showed that after the implementation of the policy, the proportion of public transportation in plan 1 and plan 2 increased by 14.04% and 9.86%, respectively, while the proportion of private cars decreased by 3.47% and 2.54%, respectively. The proportion of car trips decreased obviously, while the proportion of public transport trips increased. It can be considered that the measures have a positive effect on promoting green trips and improving the satisfaction of urban residents, and can provide a reference for relevant departments to formulate transportation policies.

Keywords: neural network, travel characteristics analysis, transportation choice, travel sharing rate, traffic resource allocation

Procedia PDF Downloads 120

Authors: Yinghui Shang, Ziqing Zhou, Rong Han, Hang Wang, Xiaodi Liu, Yong Yang

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The design of advanced amorphous solids, such as metallic glasses, with targeted properties through artificial intelligence signifies a paradigmatic shift in physical metallurgy and materials technology. Here, we developed a machine-learning architecture that facilitates the generation of metallic glasses with targeted multifunctional properties. Our architecture integrates the state-of-the-art unsupervised generative adversarial network model with supervised models, allowing the incorporation of general prior knowledge derived from thousands of data points across a vast range of alloy compositions, into the creation of data points for a specific type of composition, which overcame the common issue of data scarcity typically encountered in the design of a given type of metallic glasses. Using our generative model, we have successfully designed copper-based metallic glasses, which display exceptionally high hardness or a remarkably low modulus. Notably, our architecture can not only explore uncharted regions in the targeted compositional space but also permits self-improvement after experimentally validated data points are added to the initial dataset for subsequent cycles of data generation, hence paving the way for the customized design of amorphous solids without human intervention.

Keywords: metallic glass, artificial intelligence, mechanical property, automated generation

Procedia PDF Downloads 26

Authors: Hyeon-Kyo Lim, Tong-Il Jang, Yong-Hee Lee

Abstract:

Human error is one of the most dreaded factors that may result in unexpected accidents, especially in nuclear power plants. For accident prevention, it is quite indispensable to analyze and to manage the influence of any factor which may raise the possibility of human errors. Out of lots factors, stress has been reported to have a significant influence on human performance. Therefore, this research aimed to develop a work-related stress management program which can guarantee Fitness-for-Duty (FFD) of the workers in nuclear power plants, especially those working in main control rooms. Major stress factors were elicited through literal surveys and classified into major categories such as demands, supports, and relationships. To manage those factors, a test and intervention program based on 4-level approaches was developed over the whole employment cycle including selection and screening of workers, job allocation, and job rotation. In addition, a managerial care program was introduced with the concept of Employee-Assistance-Program (EAP) program. Reviews on the program conducted by ex-operators in nuclear power plants showed responses in the affirmative, and suggested additional treatment to guarantee high performance of human workers, not in normal operations but also in emergency situations.

Keywords: human error, work performance, work stress, Fitness-For-Duty (FFD), Employee Assistance Program (EAP)

Procedia PDF Downloads 390

Authors: Jing Wang, Yong Wang

Abstract:

For organizational development, employee well-being is critical and has been influenced deeply by character strengths. Therefore, investigating the relationship between character strengths and employee well-being and its inner mechanism is crucial. In this study, we explored the features of Chinese employees' character strengths, studied the relationship between character strengths and employees' subjective well-being, work well-being and psychological well-being respectively, and examined the mediating effect of work-family relationship (both enrichment and conflict). An online survey was conducted. The results showed that: (1) The top five character strengths of Chinese employees were gratitude, citizenship, kindness, appreciation of beauty and excellence, justice, while the bottom five ones were creativity, authenticity, bravery, spirituality, open-mindedness. (2) Subjective well-being was significantly correlated to courage, humanity, transcendence and justice. Work well-being was significantly correlated to wisdom, courage, humanity, justice and transcendence. Psychological well-being was significantly correlated to all the above five character strengths and temperance. (3) Wisdom and humanity influenced Chinese employees’ subjective well-being through work-family enrichment. Justice enhanced psychological well-being via work-family enrichment; meanwhile, it also played a positive role in subjective well-being, work well-being, and psychological well-being by decreasing the family-work conflict. At the end of this paper, some theoretical and practical contributions to organizational management were further discussed.

Keywords: character strengths, work-family conflict, work-family enrichment, employee well-being, work well-being

Procedia PDF Downloads 373

Authors: Jae-Hyung Jin, Kyung-Tae Lee, Yee-Seul So, Eunji Jeong, Yeonseon Lee, Dongpil Lee, Dong-Gi Lee, Yong-Sun Bahn

Abstract:

Cryptococcus neoformans causes cryptococcal meningoencephalitis mainly in immunocompromised patients as well as immunocompetent people. But therapeutic options are limited to treat cryptococcosis. Some signaling pathways including cyclic AMP pathway, MAPK pathway, and calcineurin pathway play a central role in the regulation of the growth, differentiation, and virulence of C. neoformans. To understand signaling networks regulating the virulence of C. neoformans, we selected the 114 putative phosphatase genes, one of the major components of signaling networks, in the genome of C. neoformans. We identified putative phosphatases based on annotation in C. neoformans var. grubii genome database provided by the Broad Institute and National Center for Biotechnology Information (NCBI) and performed a BLAST search of phosphatases of Saccharomyces cerevisiae, Aspergillus nidulans, Candida albicans and Fusarium graminearum to Cryptococcus neoformans. We classified putative phosphatases into 14 groups based on InterPro phosphatase domain annotation. Here, we constructed 170 signature-tagged gene-deletion strains through homologous recombination methods for 91 putative phosphatases. We examined their phenotypic traits under 30 different in vitro conditions, including growth, differentiation, stress response, antifungal resistance and virulence-factor production.

Keywords: human fungal pathogen, phosphatase, deletion library, functional genomics

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Authors: Yijun Shao, Yan Cheng, Rashmee U. Shah, Charlene R. Weir, Bruce E. Bray, Qing Zeng-Treitler

Abstract:

Deep neural network (DNN) models are being explored in the clinical domain, following the recent success in other domains such as image recognition. For clinical adoption, outcome prediction models require explanation, but due to the multiple non-linear inner transformations, DNN models are viewed by many as a black box. In this study, we developed a deep neural network model for predicting 1-year mortality of patients who underwent major cardio vascular procedures (MCVPs), using temporal image representation of past medical history as input. The dataset was obtained from the electronic medical data warehouse administered by Veteran Affairs Information and Computing Infrastructure (VINCI). We identified 21,355 veterans who had their first MCVP in 2014. Features for prediction included demographics, diagnoses, procedures, medication orders, hospitalizations, and frailty measures extracted from clinical notes. Temporal variables were created based on the patient history data in the 2-year window prior to the index MCVP. A temporal image was created based on these variables for each individual patient. To generate the explanation for the DNN model, we defined a new concept called impact score, based on the presence/value of clinical conditions’ impact on the predicted outcome. Like (log) odds ratio reported by the logistic regression (LR) model, impact scores are continuous variables intended to shed light on the black box model. For comparison, a logistic regression model was fitted on the same dataset. In our cohort, about 6.8% of patients died within one year. The prediction of the DNN model achieved an area under the curve (AUC) of 78.5% while the LR model achieved an AUC of 74.6%. A strong but not perfect correlation was found between the aggregated impact scores and the log odds ratios (Spearman’s rho = 0.74), which helped validate our explanation.

Keywords: deep neural network, temporal data, prediction, frailty, logistic regression model

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Authors: Chun-Liang Wu, Kai-Ping Shaw, Cheng-Ping Yu, Wu-Chien Chien, Hsiao-Ting Chen, Shao-Huang Wu

Abstract:

Objective: This study analyzed three criminal judicial cases. We applied the damage analysis of the two vehicles to verify other evidence, such as dashboard camera records of each accident, reconstruct the scenes, and pursue the truth. Methods: Evidence analysis, the method is to collect evidence and the reason for the results in judicial procedures, then analyze the involved damage evidence to verify other evidence. The collision damage analysis method is to inspect the damage to the vehicles and utilize the principles of tool mark analysis, Newtonian physics, and vehicle structure to understand the relevant factors when the vehicles collide. Results: Case 1: Sedan A turned right at the T junction and collided with Scooter B, which was going straight on the left road. The dashboard camera records showed that the left side of Sedan A’s front bumper collided with the body of Scooter B and rider B. After the analysis of the study, the truth was that the front of the left side of Sedan A impacted the right pedal of Scooter B and the right lower limb of rider B. Case 2: Sedan C collided with Scooter D on the left road at the crossroads. The dashboard camera record showed that the left side of the Sedan C’s front bumper collided with the body of Scooter D and rider D. After the analysis of the study, the truth was that the left side of the Sedan C impacted the left side of the car body and the front wheel of Scooter D and rider D. Case 3: Sedan E collided with Scooter F on the right road at the crossroads. The dashboard camera record showed that the right side of the Sedan E’s front bumper collided with the body of Scooter F and rider F. After the analysis of the study, the truth was that the right side of the front bumper and the right side of the Sedan F impacted the Scooter. Conclusion: The application of collision damage analysis in the reconstruction of a sedan-scooter collision could discover the truth and provide the basis for judicial justice. The cases and methods could be the reference for the road safety policy.

Keywords: evidence analysis, collision damage analysis, accident reconstruction, sedan-scooter collision, dashboard camera records

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Authors: Zhiyuan Jia, Xiuxiu Sun, Yong Chen, Liu Hai, Shuangqing Li

Abstract:

The engine cooling water and exhaust gas contain a large amount of available energy. In order to improve energy efficiency, a steam injection technology based on waste heat recovery is proposed. The models of cooling water waste heat utilization, exhaust gas waste heat utilization, and exhaust gas-cooling water waste heat utilization were constructed, and the effects of the three modes on the performance of steam injection were analyzed, and then the feasibility of in-cylinder water injection steam technology based on waste heat recovery was verified. The research results show that when the injection water flow rate is 0.10 kg/s and the temperature is 298 K, at a cooling water temperature of 363 K, the maximum temperature of the injection water heated by the cooling water can reach 314.5 K; at an exhaust gas temperature of 973 K and an exhaust gas flow rate of 0.12 kg/s, the maximum temperature of the injection water heated by the exhaust gas can reach 430 K; Under the condition of cooling water temperature of 363 K, exhaust gas temperature of 973 K and exhaust gas flow rate of 0.12 kg/s, after cooling water and exhaust gas heating, the maximum temperature of the injection water can reach 463 K. When the engine is 1200 rpm, the water injection volume is 30 mg, and the water injection time is 36°CA, the engine power increases by 2% and the fuel consumption is reduced by 2.6%.

Keywords: cooling water, exhaust gas, extended range engine, steam injection, waste heat recovery

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Authors: Namsoo Kim, So-Hee Son, Jin-Soo Maeng, Yong-Jin Cho, Chong-Tai Kim

Abstract:

It has been reported that some enzymes such as trypsin and Alcalase 2.4L are tolerant to a medium high pressure of 300 MPa and preparation of protein hydrolyzates under 300 MPa was advantageous with regard to hydrolysis rate and thus production yield compared with the counterpart under ambient pressure.1,2) In this study, nine fish comprising halibut, soft shell clam and carp were hydrolyzed using Flavourzyme 500MG only, and the combination of Flavourzyme 500 mg, Alcalase 2.4 L, Marugoto E, and Protamex under 300 MPa. Then, the effects of single and multiple protease treatments were determined with respect to contents of soluble solid (SS) and soluble nitrogen, sensory attributes, electrophoretic profiles, and HPLC peak patterns of the fish hydrolyzates (FHs) from various species. The contents of SS of the FHs were quite species-specific and the hydrolyzates of halibut showed the highest SS contents. At this point, multiple protease treatment increased SS content conspicuously in all fish tested. The contents of total soluble nitrogen and TCA-soluble nitrogen were well correlated with those of SS irrespective of fish species and methods of enzyme treatment. Also, it was noticed that multiple protease treatment improved sensory attributes of the FHs considerably. Electropherograms of the FHs showed fast migrating peptide bands that had the molecular masses mostly lower than 1 kDa and this was confirmed by peptide patterns from HPLC analysis for some FHs that had good sensory quality.

Keywords: production, fish hydrolyzates, protease treatments, high pressure

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Authors: Agampodi Promoda Perera, Yong Shin, Mi Kyoung Park

Abstract:

The successful detection of pathogenic bacteria in blood provides important information for early detection, diagnosis and the prevention and treatment of infectious diseases. Silicon microring resonators are refractive-index-based optical biosensors that provide highly sensitive, label-free, real-time multiplexed detection of biomolecules. We demonstrate the technique of using GO (graphene oxide) to enhance the signal output of the silicon microring optical sensor. The activated carboxylic groups in GO molecules bind directly to single stranded DNA with an amino modified 5’ end. This conjugation amplifies the shift in resonant wavelength in a real-time manner. We designed a capture probe for strain Staphylococcus aureus of 21 bp and a longer complementary target sequence of 70 bp. The mismatched target sequence we used was of Streptococcus agalactiae of 70 bp. GO is added after the complementary binding of the probe and target. GO conjugates to the unbound single stranded segment of the target and increase the wavelength shift on the silicon microring resonator. Furthermore, our results show that GO could successfully differentiate between the mismatched DNA sequences from the complementary DNA sequence. Therefore, the proposed concept could effectively enhance sensitivity of pathogen detection sensors.

Keywords: label free biosensor, pathogenic bacteria, graphene oxide, diagnosis

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