• Title/Summary/Keyword: model studies

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A Neural Network Model for Building Construction Projects Cost Estimating

  • El-Sawalhi, Nabil Ibrahim;Shehatto, Omar
    • Journal of Construction Engineering and Project Management
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    • v.4 no.4
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    • pp.9-16
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    • 2014
  • The purpose of this paper is to develop a model for forecasting early design construction cost of building projects using Artificial Neural Network (ANN). Eighty questionnaires distributed among construction organizations were utilized to identify significant parameters for the building project costs. 169 case studies of building projects were collected from the construction industry in Gaza Strip. The case studies were used to develop ANN model. Eleven significant parameters were considered as independent input variables affected on "project cost". The neural network model reasonably succeeded in estimating building projects cost without the need for more detailed drawings. The average percentage error of tested dataset for the adapted model was largely acceptable (less than 6%). Sensitivity analysis showed that the area of typical floor and number of floors are the most influential parameters in building cost.

Development of Analysis Model for Metro Railway Power System Using PSCAD/EMTDC (PSCAD/EMTDC를 이용한 전기철도 전력공급시스템 해석모델개발)

  • Jang, Gil-Soo;Cha, Jun-Min
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.55 no.11
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    • pp.463-467
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    • 2006
  • A direct current electric power system is one of the most important power source in a metro railway system. As railway system is growing up today, the importance of DC electric power system is emphasized. The study for systemization and standardization of design and operation technique in DC electric power system is undergoing nowadays. For these studies, the development of standard analysis model for metro railway electric power system is required. In this paper, a standard analysis model for metro railway electric power system which is using PSCAD/EMTDC program is proposed. The proposed model is explained and the validity is shown by using the case studies.

Analysis of the Causal Relationships Among the Factors that Influence the Use of Mobile Phone Services (국내 이동전화 서비스 이용에 영향을 미치는 요인에 관한 연구)

  • Suh, Bo-Mil;Wee, Kyeong-Woo;Yoo, Jin-Soo
    • Journal of Information Technology Services
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    • v.6 no.1
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    • pp.47-63
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    • 2007
  • A lot of researchers have been interested in the factors influencing the use of mobile phone services. Most of the previous studies, however, verified only the research models developed by the authors. They did not consider which model agrees better with the real situation. This study presents six alternative models based on various previous studies, and compares the data fitness of the models. A Web survey of mobile phone users collected 2,217 cases. Statistical analyses, using SEM (Structural Equation Modeling), show that the fitness of the simplest alternative model is better than that of any other model. The simplest model has no causal relationship among exogenous factors, and proposes that all of exogenous factors have direct impacts on the customer satisfaction. In addition, the analyses say that corporate and brand image and additional service are more important than the other exogenous factors such as communication quality.

Understanding Relationships Among Risk Factors in Container Port Operation UsingBayesian Network

  • Tsenskhuu Nyamjav;Min-Ho Ha
    • Journal of Navigation and Port Research
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    • v.47 no.2
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    • pp.93-99
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    • 2023
  • This study aimed to determine relationships among risk factors influencing container port operation using Bayesian network. Risk factors identified from prior studies were classified into five groups: human error, machinery error, environmental risk, security risk, and natural disasters. P anel experts discussed identified risk factors to fulfil conditional probability tables of the interdependence model. The interdependence model was also validated by sensitivity analysis and provided an interrelation of factors influencing the direction of each other. Results of the interdependence model were partially in line with results from prior studies while practices in the global port industry confirmed interrelationships of risk factors. In addition, the relationship between top-ranked risk factors can provide a schematic drawing of the model. Accordingly, results of this study can expand the prior research in the Korean port industry, which may help port authorities improve risk management and reduce losses from the risk.

CR-M-SpanBERT: Multiple embedding-based DNN coreference resolution using self-attention SpanBERT

  • Joon-young Jung
    • ETRI Journal
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    • v.46 no.1
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    • pp.35-47
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    • 2024
  • This study introduces CR-M-SpanBERT, a coreference resolution (CR) model that utilizes multiple embedding-based span bidirectional encoder representations from transformers, for antecedent recognition in natural language (NL) text. Information extraction studies aimed to extract knowledge from NL text autonomously and cost-effectively. However, the extracted information may not represent knowledge accurately owing to the presence of ambiguous entities. Therefore, we propose a CR model that identifies mentions referring to the same entity in NL text. In the case of CR, it is necessary to understand both the syntax and semantics of the NL text simultaneously. Therefore, multiple embeddings are generated for CR, which can include syntactic and semantic information for each word. We evaluate the effectiveness of CR-M-SpanBERT by comparing it to a model that uses SpanBERT as the language model in CR studies. The results demonstrate that our proposed deep neural network model achieves high-recognition accuracy for extracting antecedents from NL text. Additionally, it requires fewer epochs to achieve an average F1 accuracy greater than 75% compared with the conventional SpanBERT approach.

A REVIEW OF STUDIES ON OPERATOR'S INFORMATION SEARCHING BEHAVIOR FOR HUMAN FACTORS STUDIES IN NPP MCRS

  • Ha, Jun-Su;Seong, Poong-Hyun
    • Nuclear Engineering and Technology
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    • v.41 no.3
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    • pp.247-270
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    • 2009
  • This paper reviews studies on information searching behavior in process control systems and discusses some implications learned from previous studies for use in human factors studies on nuclear power plants (NPPs) main control rooms (MCRs). Information searching behavior in NPPs depends on expectancy, value, salience, and effort. The first quantitative scanning model developed by Senders for instrument panel monitoring considered bandwidth (change rate) of instruments as a determining factor in scanning behavior. Senders' model was subsequently elaborated by other researchers to account for value in addition to bandwidth. There is also another type of model based on the operator's situation awareness (SA) which has been developed for NPP application. In these SA-based models, situation-event relations or rules on system dynamics are considered the most significant factor forming expectancy. From the review of previous studies it is recommended that, for NPP application, (1) a set of symptomatic information sources including both changed and unchanged symptoms should be considered along with bandwidth as determining factors governing information searching (or visual sampling) behavior; (2) both data-driven monitoring and knowledge-driven monitoring should be considered and balanced in a systematic way; (3) sound models describing mechanisms of cognitive activities during information searching tasks should be developed so as to bridge studies on information searching behavior and design improvement in HMI; (4) the attention-situation awareness (A-SA) modeling approach should be recognized as a promising approach to be examined further; and (5) information displays should be expected to have totally different characteristics in advanced control rooms. Hence much attention should be devoted to information searching behavior including human-machine interface (HMI) design and human cognitive processes.

Recent Research Trends in Korean Medicine Treatment of Diabetes mellitus (당뇨의 한의학적 치료에 대한 최근 연구동향)

  • Jung, Han-Sung;Yu, Jung-Suk;Song, Beom-Yong
    • Journal of Pharmacopuncture
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    • v.11 no.4
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    • pp.65-77
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    • 2008
  • Objective The purpose of this study was to analyze the directions of Korean Medicine treatment of diabetes mellitus. Methods We reviewed the 52 studies about diabetes mellitus which had been published from 2000 to 2007. We selected those studies from the search engine of the web site of five journals. Those were the Journal of Korean Oriental Medical Society, Korean Journal of Oriental Physiology & Pathology, the Journal of Korean Acupuncture & Moxibustion Society, Korean Journal of Oriental Internal Medicine and the Journal of Korean Pharmacopuncture Institute. Results 1. The types of diabetes mellitus model in studies were the model used Alloxan(2cases), the model used Streptozotocin(41cases), NOD mice(1case), ob/ob mice(1case), db/db mice(5cases) and rats fed highfat diet(2cases). 2. The types of method in studies were pharmacopuncture(8cases), herbal medcine(47case) and both pharmacopuncture and herbal medcine(3cases). the types of materials in studies were single herb(24cases), multiple herbs(32cases) and both single and multiple herbs(4cases). 3. The types of evaluation criteria in studies were glucose, pancreas, liver, kidney, serum lipid, oxidative stress, nervous system, vascular system and immunity. Conclusions There have been reported many studies of diabetes mellitus in Korean Medicine. It requires to study further types of diabetes mellitus, kinds of herbs and complications of diabetes mellitus for Korean Medicine treatment of diabetes mellitus was covered the ground.

Trend of Disabled Person Care for Establishment of Visiting Health Management Model for the Disabled (장애인 방문건강관리 모형 구축을 위한 장애인 진료 동향 조사)

  • Kim, Eun-Bi;Lee, Jae-Won;Park, Sun-Young;Park, In-Hwa;Hwang, Man-Suk;Hwang, Eui-Hyoung;Song, Yun-Kyung
    • Journal of Korean Medicine Rehabilitation
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    • v.29 no.4
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    • pp.61-72
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    • 2019
  • Objectives We analyzed and organized present studies related to medical care for the disabled to establish an appropriate model of visiting health management for the people with disability. Methods To analyse study of medical care for the disabled, 11 electonic databases (PubMed, Chinese Academic Journals, EMBASE, Cochrane Library, Medline, Oasis, KMBASE, KISS, KISTI, NDSL, RISS) were searched from 2009 to 2018. There's no limit to the type of study. Results The search showed 20 domestic studies and 113 foreign studies that were screened for final inclusion of 37 studies. The all of domestic studies were relevant to dental research. The foreign studies have reported on the treatment of underlying diseases and medical services for the disabled. Conclusions Most studies have reported that government institutional support were needed for systematic treatment of the disabled. In the future, institutional support would be needed to establish the model of oriental doctor's visiting health management for the disabled.

An Integrative Approach for Strengthening Continual Adoption of e-Government Services : An Empirical Study (전자정부 서비스의 지속적 수용 강화를 위한 통합적 접근 : 실증연구)

  • Lim, Se Hun
    • Journal of Information Technology Applications and Management
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    • v.20 no.1
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    • pp.19-41
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    • 2013
  • This study analyzed the users acceptance of e-Government services. Many IT(Information Technology) adoption studies appeared the TAM(technology adoption model) of Davis[1989] as a theoretical background. The TAM composed of three factors those are the perceived easy of use, the perceived usefulness, and intention to adoption of IT. However, TAM did not explain the consequences of intention to adoption and antecedents of the ease of use and usefulness in IT adoption. To overcome limitations of TAM, many technology acceptance studies done. In this study, the researcher suggested the IT acceptance model for explaining users adoption of e-Government service based on the model of IT acceptance of Wixom and Todd[2005]. The model of Wixom and Todd[2005] based on the TAM of Davis[1989], IT adoption model of Taylor and Todd[1995] and, IS(Information Systems) success model of Delone and Mclean[1992, 2003]. For testing our research model, the researcher collected data from 200 users of e-Government services. The researcher analyzed in measurement model and structural model using statistical software. This study analyzed relationships among interaction, information quality, Web systems quality, satisfaction, ease of use, usefulness, and attitude to explain and predict influences of the users acceptance of e-Government services. The results of this study will provide useful information about develop a strategy for usage spread of e-Government services.

Mesoscale modelling of concrete for static and dynamic response analysis -Part 1: model development and implementation

  • Tu, Zhenguo;Lu, Yong
    • Structural Engineering and Mechanics
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    • v.37 no.2
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    • pp.197-213
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    • 2011
  • Concrete is a heterogeneous material exhibiting quasi-brittle behaviour. While homogenization of concrete is commonly accepted in general engineering applications, a detailed description of the material heterogeneity using a mesoscale model becomes desirable and even necessary for problems where drastic spatial and time variation of the stress and strain is involved, for example in the analysis of local damages under impact, shock or blast load. A mesoscale model can also assist in an investigation into the underlying mechanisms affecting the bulk material behaviour under various stress conditions. Extending from existing mesoscale model studies, where use is often made of specialized codes with limited capability in the material description and numerical solutions, this paper presents a mesoscale computational model developed under a general-purpose finite element environment. The aim is to facilitate the utilization of sophisticated material descriptions (e.g., pressure and rate dependency) and advanced numerical solvers to suit a broad range of applications, including high impulsive dynamic analysis. The whole procedure encompasses a module for the generation of concrete mesoscale structure; a process for the generation of the FE mesh, considering two alternative schemes for the interface transition zone (ITZ); and the nonlinear analysis of the mesoscale FE model with an explicit time integration approach. The development of the model and various associated computational considerations are discussed in this paper (Part 1). Further numerical studies using the mesoscale model for both quasi-static and dynamic loadings will be presented in the companion paper (Part 2).