• Title/Summary/Keyword: Modeling

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Application of Patient-Specific 3D-Printed Orthopedic Splint for Bone Fracture in Small Breed Dogs

  • Kwangsik Jang;Eun Joo Jang;Yo Han Min;Kyung Mi Shim;Chunsik Bae;Seong Soo Kang;Se Eun Kim
    • Journal of Veterinary Clinics
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    • v.40 no.4
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    • pp.268-275
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    • 2023
  • In this paper, we designed 3D-printed orthopedic splint models for patient-specific external coaptation on fracture healing and analyzed the stability of the models through finite element method (FEM) analysis under compressive load conditions. Polylactic acid (PLA) and acrylonitrile-butadiene-styrene (ABS) based 3D splint models of the thicknesses 1, 3, 5 and 7 mm were designed, and Peak von Mises stress (PVMS) and maximum displacement (MD) of the models were analyzed by FEM under compressive loads of 50, 100, 150, and 200 N. The FEM results indicated that PVMS and MD values, regardless of material, had a negative correlation with the thickness of the models and a positive correlation with the compressive load. There was a risk of splint deformation under conditions more extreme than 100 N with 5 mm thickness. For successful clinical application of 3D-printed orthopedic splints in veterinary medicine, it is recommended that the splint should be produced not less than 5 mm thickness. Also, it is expected to be stable when the splint is applied to situations with a compressive load of 100 N or less. There is an advantage of overcoming the limitations of the existing bandage method through 3D-printing technology as well as verifying the stability through 3D modeling before application. Such 3D printing technology will be widely used in veterinary medicine and various fields as well as orthopedics.

Power Distribution Optimization of Multi-stack Fuel Cell Systems for Improving the Efficiency of Residential Fuel Cell (주택용 연료전지 효율 향상을 위한 다중 스택 연료전지 시스템의 전력 분배 최적화)

  • TAESEONG KANG;SEONGHYEON HAM;HWANYEONG OH;YOON-YOUNG CHOI;MINJIN KIM
    • Transactions of the Korean hydrogen and new energy society
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    • v.34 no.4
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    • pp.358-368
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    • 2023
  • The fuel cell market is expected to grow rapidly. Therefore, it is necessary to scale up fuel cells for buildings, power generation, and ships. A multi-stack system can be an effective way to expand the capacity of a fuel cell. Multi-stack fuel cell systems are better than single-stack systems in terms of efficiency, reliability, durability and maintenance. In this research, we developed a residential fuel cell stack and system model that generates electricity using the fuel cell-photovoltaic hybrid system. The efficiency and hydrogen consumption of the fuel cell system were calculated according to the three proposed power distribution methods (equivalent, Daisy-chain, and optimal method). As a result, the optimal power distribution method increases the efficiency of the fuel cell system and reduces hydrogen consumption. The more frequently the multi-stack fuel cell system is exposed to lower power levels, the greater the effectiveness of the optimal power distribution method.

Role of Cel5H protein surface amino acids in binding with clay minerals and measurements of its forces

  • Renukaradhya K. Math;Nagakumar Bharatham;Palaksha K. Javaregowda;Han Dae Yun
    • Applied Microscopy
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    • v.51
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    • pp.17.1-17.10
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    • 2021
  • Our previous study on the binding activity between Cel5H and clay minerals showed highest binding efficiency among other cellulase enzymes cloned. Here, based on previous studies, we hypothesized that the positive amino acids on the surface of Cel5H protein may play an important role in binding to clay surfaces. To examine this, protein sequences of Bacillus licheniformis Cel5H (BlCel5H) and Paenibacillus polymyxa Cel5A (PpCel5A) were analyzed and then selected amino acids were mutated. These mutated proteins were investigated for binding activity and force measurement via atomic force microscopy (AFM). A total of seven amino acids which are only present in BlCel5H but not in PpCel5A were selected for mutational studies and the positive residues which are present in both were omitted. Of the seven selected surface lysine residues, only three mutants K196A(M2), K54A(M3) and K157T(M4) showed 12%, 7% and 8% less clay mineral binding ability, respectively compared with wild-type. The probable reason why other mutants did not show altered binding efficiency might be due to relative location of amino acids on the protein surface. Meanwhile, measurement of adhesion forces on mica sheets showed a well-defined maximum at 69±19 pN for wild-type, 58±19 pN for M2, 53±19 pN for M3, and 49±19 pN for M4 proteins. Hence, our results demonstrated that relative location of surface amino acids of Cel5H protein especially positive charged amino acids are important in the process of clay mineral-protein binding interaction through electrostatic exchange of charges.

Factors Influencing the Purchase Intention of EVs Among Korean and Chinese Consumers

  • Jian Cong;Kyoung-Suk Choi;Tongshui Xia
    • Journal of Korea Trade
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    • v.27 no.4
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    • pp.77-100
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    • 2023
  • Purpose - Using the Model of Goal-Directed Behavior (MGB), this study identifies the critical factors that influence consumer intention to purchase an electric vehicle (EV). This study also provides differentiated policy implications to the Korean and Chinese governments and EV-related companies for the expansion of the EV market in both countries by comparing consumers' perceptions of EV purchase intentions. Design/methodology - Our extended MGB model adds to the standard model consideration of financial incentives, perceived risks, and environmental concerns. An online survey was conducted of Korean and Chinese consumers. Based on the collected responses, all tested hypotheses were verified using PLS-SEM (Partial Least Squares-Structural Equation Modeling). Differences in the path analysis results between Korea and China were compared and verified using Henseler's MGA (multi-group analysis), the parametric test, and the Welch-Satterthwaite test. Findings - The most critical factor that influences the intent to purchase an EV in consumers from both countries is personal desire. PBC and SN were identified as the critical factors that respectively increase personal desire in Korea and China. In addition, in Korea, among the three factors EC, FIP, and PR, environmental concerns were found to have the most significant impact on attitudes and purchase intention. In contrast, in China, economic factors (specifically financial incentives) had greater importance than environmental issues. Originality/value - This study has academic contributions in that it presents a new research model that includes financial incentive policies, environmental concerns, and perceived risk variables based on the MGB to explore consumers' purchase intentions. This study can also make a practical contribution in that it provides some meaningful implications to the governments and EV-related companies of both countries based on the differences in the analysis results of the Korean and Chinese markets.

Panic Disorder Symptom Care System Based on Context Awareness (상황인식 기반의 공황장애 증상 관리 시스템)

  • Choi, Dong-Oun;Huan, Meng;Kang, Yun-Jeong
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.4
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    • pp.63-70
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    • 2019
  • We extract the symptom of panic disorder from the context awareness environment. It extracts body context information through natural movement that exists in everyday life and uses a component of panic disorder. The ontology theory can be used to provide information on the degree of symptoms of panic disorder through inference process. For the components of panic disorder to the information processing based on ontology are defined as Classes. Panic disorder index is expressed through ontology modeling so that the condition of panic disorder can be known. The derivation of panic disorder component and panic disorder index will enable context awareness based information service for panic disorder. The context information is periodically synchronized with the context awareness on based device. Panic disorder can be used to improve the lifestyle of panic disorder.

The Relationship between National Identity and Attitudes towards Immigrants - A Comparison of Korean, Chinese and Japanese University Students (국민정체성과 다문화태도의 관계-한·중·일 대학생을 중심으로)

  • Kim, Hyun-suk;Choi, Song-sik;Kim, Hee-Jae
    • Journal of International Area Studies (JIAS)
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    • v.15 no.2
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    • pp.141-168
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    • 2011
  • The purpose of this study was to investigate the relationship between national identity and attitudes towards immigrants among Korean, Chinese and Japanese univ. students. The subjects were univ. students of Korean(433), Chinese (495) and Japanese(477). Data were analyzed by Factor analysis, ANOVA, Scheffe, Structural Equation Modeling, multi-group analysis. The results are following : First, ethnic and civic identity both was the highest in chinese univ. students. Ethnic identity was the lowest in Korean univ. students, and civic identity was the lowest in Japanese univ. students. Second, attitudes towards immigrants among Korean, Chinese and Japanese Univ. Students differed from items of perceived threat. Third, each sub-factor of national identity influenced mutual relation rather than independent on attitude towards immigrants. The impact of national identity on the attitudes towards immigrants, that of Japanese univ. students has significantly highest, but those of Korean and Chinese univ. students was not affected.

A Comparative Study on the Socio-Technical Transition Theories: Integrated Approach to Transition Policy Design and Implementation (사회-기술 전환이론 비교 연구 - 전환정책 설계와 운영을 위한 통합적 접근 -)

  • Lee, Youngseok;Kim, Byung-Keun
    • 한국정책학회보
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    • v.23 no.4
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    • pp.179-209
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    • 2014
  • Transition studies have been gaining attention among innovation researchers from the early 1990's mainly influenced by emerging global agendas on sustainability. In this paper, we review research issues and trends focusing on four prominent transition theories - Technological innovation systems, Multi-level perspective, Transition management and Strategic niche management. After reviewing main characteristics, research trends and debates of each theory from established literatures, we conduct comparative analysis of these theories and suggest integrated framework that can be considered when modeling transition policy. This integrated framework is applied to the case study on smart-grid policy of Korea.

Adding AGC Case Studies to the Educator's Tool Chest

  • Schaufelberger, John;Rybkowski, Zofia K.;Clevenger, Caroline
    • International conference on construction engineering and project management
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    • 2022.06a
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    • pp.1226-1236
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    • 2022
  • Because students majoring in construction-related fields must develop a broad repository of knowledge and skills, effective transferal of these is the primary focus of most academic programs. While inculcation of this body of knowledge is certainly critical, actual construction projects are complicated ventures that involve levels of risk and uncertainty, such as resistant neighboring communities, unforeseen weather conditions, escalating material costs, labor shortages and strikes, accidents on jobsites, challenges with emerging forms of technology, etc. Learning how to develop a level of discernment about potential ways to handle such uncertainty often takes years of costly trial-and-error in the proverbial "school of hard knocks." There is therefore a need to proactively expedite the development of a sharpened intuition when making decisions. The AGC Education and Research Foundation case study committee was formed to address this need. Since its inception in 2011, 14 freely downloadable case studies have thus far been jointly developed by an academics and industry practitioners to help educators elicit varied responses from students about potential ways to respond when facing an actual project dilemma. AGC case studies are typically designed to focus on a particular concern and topics have thus far included: ethics, site logistics planning, financial management, prefabrication and modularization, safety, lean practices, preconstruction planning, subcontractor management, collaborative teamwork, sustainable construction, mobile technology, and building information modeling (BIM). This session will include an overview of the history and intent of the AGC case study program, as well as lively interactive demonstrations and discussions on how case studies can be used both by educators within a typical academic setting, as well as by industry practitioners seeking a novel tool for their in-house training programs.

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Theoretical formulation for calculating elastic lateral stiffness in a simple steel frame equipped with elliptic brace

  • Jouneghani, Habib Ghasemi;Fanaie, Nader;Haghollahi, Abbas
    • Steel and Composite Structures
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    • v.45 no.3
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    • pp.437-454
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    • 2022
  • Elliptic-braced simple resisting frame as a new lateral bracing system installed in the middle bay of frame in building facades has been recently introduced. This system not only creates a problem for opening space from the architectural viewpoint but also improves the structural behavior. Despite the researches on the seismic performance of lateral bracing systems, there are few studies performed on the effect of the stiffness parameters on the elastic story drift and calculation of period in simple braced steel frames. To overcome this shortcoming, in this paper, for the first time, an analytical solution is presented for calculating elastic lateral stiffness in a simple steel frame equipped with elliptic brace subjected to lateral load. In addition, for the first time, in this study, a precise formulation has been developed to evaluate the elastic stiffness variation in a steel frame equipped with a two-dimensional single-story single-span elliptic brace using strain energy and Castigliano's theorem. Thus, all the effective factors, including axial and shear loads as well as bending moments of elliptic brace could be considered. At the end of the analysis, the lateral stiffness can be calculated by an improved and innovative relation through the energy method based on the geometrical properties of the employed sections and specification of the used material. Also, an equivalent element of an elliptic brace was presented for the ease of modeling and use in linear designs. Application of the proposed relation have been verified through a variety of examples in OpenSees software. Based on the results, the error percentage between the elastic stiffness derived from the developed equations and the numerical analyses of finite element models was very low and negligible.

BERT & Hierarchical Graph Convolution Neural Network based Emotion Analysis Model (BERT 및 계층 그래프 컨볼루션 신경망 기반 감성분석 모델)

  • Zhang, Junjun;Shin, Jongho;An, Suvin;Park, Taeyoung;Noh, Giseop
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2022.10a
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    • pp.34-36
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    • 2022
  • In the existing text sentiment analysis models, the entire text is usually directly modeled as a whole, and the hierarchical relationship between text contents is less considered. However, in the practice of sentiment analysis, many texts are mixed with multiple emotions. If the semantic modeling of the whole is directly performed, it may increase the difficulty of the sentiment analysis model to judge the sentiment, making the model difficult to apply to the classification of mixed-sentiment sentences. Therefore, this paper proposes a sentiment analysis model BHGCN that considers the text hierarchy. In this model, the output of hidden states of each layer of BERT is used as a node, and a directed connection is made between the upper and lower layers to construct a graph network with a semantic hierarchy. The model not only pays attention to layer-by-layer semantics, but also pays attention to hierarchical relationships. Suitable for handling mixed sentiment classification tasks. The comparative experimental results show that the BHGCN model exhibits obvious competitive advantages.

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