• Title/Summary/Keyword: Hybrid-model

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Identification and risk management related to construction projects

  • Boughaba, Amina;Bouabaz, Mohamed
    • Advances in Computational Design
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    • v.5 no.4
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    • pp.445-465
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    • 2020
  • This paper presents a study conducted with the aim of developing a model of tendering based on a technique of artificial intelligence by managing and controlling the factors of success or failure of construction projects through the evaluation of the process of invitation to tender. Aiming to solve this problem, analysis of the current environment based on SWOT (Strengths, Weaknesses, Opportunities, and Threats) is first carried out. Analysis was evaluated through a case study of the construction projects in Algeria, to bring about the internal and external factors which affect the process of invitation to tender related to the construction projects. This paper aims to develop a mean to identify threats-opportunities and strength-weaknesses related to the environment of various national construction projects, leading to the decision on whether to continue the project or not. Following a SWOT analysis, novel artificial intelligence models in forecasting the project status are proposed. The basic principal consists in interconnecting the different factors to model this phenomenon. An artificial neural network model is first proposed, followed by a model based on fuzzy logic. A third model resulting from the combination of the two previous ones is developed as a hybrid model. A simulation study is carried out to assess performance of the three models showing that the hybrid model is better suited in forecasting the construction project status than RNN (recurrent neural network) and FL (fuzzy logic) models.

A Research on Dynamic Tension Response of Model Mooring Chain by Forced Oscillation Test (강제동요 시험을 이용한 모형 계류삭의 동적 응답 연구)

  • Cho, Seok-Kyu;Hong, Sa-Young;Hong, Sup;Kim, Hyun-Joe
    • Journal of Ocean Engineering and Technology
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    • v.19 no.3
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    • pp.39-46
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    • 2005
  • A series of forced oscillation tests on a model mooring chain was carried out to investigate dynamic tension characteristics. The model test was conducted at two different water depths to gather basic data for a 'truncated mooring test' and 'hybrid mooring test'. The truncated and hybrid mooring tests are important for overcoming the limitation of water depth that existed in previous model tests. The resultant tension RAO provides a good possibility of approximation of dynamic tension by equivalent weight adjustment for different water depths. Because the hybrid mooring test is an adequate combination of model test and simulation, an accurate simulation model for the mooring system is essential. The simulation results show good agreement with model test results.

A Research on Dynamic Tension Response of Model Mooring Chain by Forced Oscillation Test (강제동요 시험을 이용한 모형 계류삭의 동적 응답 연구)

  • Kim, Hyun-Joe;Hong, Sa-Young;Hong, Sup;Cho, Suk-Kyu
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2002.10a
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    • pp.134-141
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    • 2002
  • A series of forced oscillation test on model mooring chain was carried out to investigate dynamic tension characteristics. The model test was conducted at two different water depth to gather basic data for 'truncated mooring test' and 'hybrid mooring test'. The truncated and hybrid mooring test are highly recommended to overcome the limitation of water depth in model test recently. The resultant tension RAO gives good possibility of approximation of dynamic tension by equivalent weight adjustment for the ratio of water depth in different water depth. Because the hybrid mooring test is the adequate combination of model test and simulation, accurate simulation model on mooring system is essential. The simulation results show good agreement with model test results.

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Electric Model of Li-Ion Polymer Battery for Motor Driving Circuit in Hybrid Electric Vehicle

  • Lee, June-Sang;Lee, Jae-Joong;Kim, Mi-Ro;Park, In-Jun;Kim, Jung-Gu;Lee, Ki-Sik;Nah, Wan-Soo
    • Journal of Electrical Engineering and Technology
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    • v.7 no.6
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    • pp.932-939
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    • 2012
  • This paper presents an equivalent circuit model of a LIPB (Li-Ion Polymer battery) for Hybrid Electric Vehicles (HEVs). The proposed equivalent circuit can be used to predict the charging/discharging characteristics in time domain as well as the impedance characteristic analysis in frequency domain. Based on these features, a one-cell model is established as a function of Depth of Discharge (DoD), and a 48-cell model for a battery pack was also established. It was confirmed by experiment that the proposed model predict the discharging and impedance (AC) characteristics quite accurately at different constant current levels. To check the usefulness of the proposed circuit, the model was used to simulate a motor driving circuit with an Insulated Gate Bipolar Transistor (IGBT) inverter and Brushless DC (BLDC) motor, and it is confirmed that the model can calculate the battery voltage fluctuation in time domain at different DoDs.

Suspended Solid Dispersion Analysis for Coastal Areas Using Hybrid Concept of Particle and Concentration of Eulerian-Lagrangian Model (Eulerian-Lagrangian 농도 및 입자 결합모형에 의한 연안의 부유사 확산해석)

  • 서승원
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.8 no.2
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    • pp.185-192
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    • 1996
  • In order to simulate the coastal dispersion effectively, hybrid concept of operator split Eulerian-lagrangian concentration model and random-walk particle tracking model are developed. Especially the random-walk model is adequate for region with steep slope of concentration. According to model tests, it agrees perfectly with analytical solution on around the source point for therefore. ▽C $\geq$ 0.005, meanwhile it shows poor results for ▽C$\leq$0.002. trial modeling for real situation therefore, random-walk model is applied for near field henceforth Eulerian-Lagrangian concentration model is adoped for whole domain so that overall performance and accuracy can be achieved by using developed hybrid model.

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Concept Analysis and Development of Suffering -Application of Hybrid Model Method- (고통(Suffering) 개념분석과 개발 -혼종모형(Hybrid Model) 방법 적용-)

  • 강경아
    • Journal of Korean Academy of Nursing
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    • v.26 no.2
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    • pp.290-303
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    • 1996
  • There is a need to define the concept of suffering more appropriate in the context of Korean culture. This research is an attempt to analyze and develop the concept of suffering by applying the Hybrid Model suggested by Schwartz-Barcott and Kim. The data were collected from March 20, 1995 to September 17,1995. The subjects of the study were eight persons including in-patients and out-patients of a general hospital who were diagnosed as having cancer and those resting in sanatoria for natural treatment of cancer. Qualitative research methods of in-depth interview and participant observation were used for data collection. The contents of the interviews were recorded on tape. Data-analysis progressed according to the 3 phases suggested by the Hybrid Model. For each case, in-depth interview data and participant observation data were included and the attributes of suffering revealed in these data were analyzed. Finally, by summarizing the results from each case, the attributes of suffering, its dimensions, definition, and processes observed in the field were suggested. According to the results of the study, the followlng new definition of suffering is suggested : Suffering is a fundamental and inevitable experience of all human beings. When each individual experiences loss, damage, and pain which threaten one's personal integrity, suffering is perceived differently among each individual depending on their personal inner factors, one's significant others, exterior circumstances and stimuli, and the ultimate meaning of life. Suffering brings severe and unendurable distress which accompany despair, powerlessness, anxiety, bitterness, fear, anguish, guilt, depression, withdrawal and anger. The results of this study suggest that the more responsibility and burden a cancer patient felt, the more suffering she/he experienced and it tended to be more relevant to one's significant others and exterior circumstances and stimuli : the less responsibility and burden a cancer patient had, the less suffering she/he experienced and it tended to be related to one's inner factors. These findings have implications for nursing profession. When caring for patients who experience suffering, nurses need to consider the influence of responsibility, burden, and each dimension of suffering. Moreover, appropriate nursing interventions aimed at relieving pain and satisfying the spiritual need of patients experiencing loss need to be developed and implemented more widely.

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A Weight-reduction Design Method by Underframe Material Substitution in a Box-type Bodyshell with Cut-outs (Cut-out이 있는 Box형 차체의 하부구조 소재대체 경량화 설계 방법)

  • Cho, Jeonggil;Koo, Jeongseo;Jung, Hyunseung
    • Transactions of the Korean Society of Automotive Engineers
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    • v.21 no.2
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    • pp.45-54
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    • 2013
  • In this paper, a theoretical weight-reduction method was suggested to substitute an underframe material of a box-type bodyshell having cut-outs with an alternative light-weight material. To utilize the material substitution method previously developed for a box-type hybrid bodyshell not having cut-outs, we derived a box-type baseline model without cut-outs which is similar to the stiffness condition of a box-type bodyshell having cut-outs. To do this, the thicknesses of roof and walls of the baseline model were determined such that the deflection of the baseline model under a distributed vertical load condition is equal to the sum of the theoretical section deflections of the original box model with cut-outs. Next, to derive a hybrid bodyshell by under-frame material substitution, the material substitution method for a box-type hybrid bodyshell without cut-outs was applied to the box-type baseline model. Finally, we compared the FE simulation results of the derived hybrid bodyshells having cut-outs for various materials with the theoretical results of the suggested method, and we obtained their good correlations.

Development of Hybrid Spatial Information Model for National Base Map (국가기본도용 Hybrid 공간정보 모델 개발)

  • Hwang, Jin Sang;Yun, Hong Sik;Yoo, Jae Yong;Cho, Seong Hwan;Kang, Seong Chan
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.4_1
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    • pp.335-341
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    • 2014
  • The main goal of this study is on developing a proper brand-new data of national base map and Data Based(DB) model for new information technology environments. To achieve this goal, we generated a brand-new Hybrid spatial information model which is specialized in the spatio-temporal map structure, the framework map for information integration, and the multiple-layered topology structure. The DB structure was designed to reflect the change of objections by adding a new dimension of 'time' in the spartial information, while the infrastructure was able to connect/converge with other information by giving the unique ID and multi-scale fusion map structure. Furthermore, the topology and multi visualization structure, including indoor and basement information, were designed to overcome limitations of expressing in 2 dimension map. The result from the performance test, which was based on the Hybrid spatial information model, confirms the possibility in advanced national base map and conducted DB model through implementing various information and spatiotemporal connections.

Finite Element Analysis on the Strength Safety of a Hybrid Alarm Valve (복합알람밸브의 강도안전성에 관한 유한요소해석)

  • Kim, Chung-Kyun;Kim, Tae-Hwan
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.2
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    • pp.221-224
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    • 2012
  • This paper presents the strength safety of a hybrid alarm valve by a finite element analysis. The stress and strain of a conventional hybrid alarm valve are calculated for the given maximum test pressure of 2MPa. Especially, the FEM computed maximum stress of a conventional hybrid valve is only 18.6% of yield strength, 370MPa. This means that the conventional valve is designed with a thick thickness of a valve structure. But, new hybrid alarm valve model, which is developed by optimized design method in this study, shows more low level of 43% in maximum stress and strain compared with that of a conventional hybrid valve. These results may recommend the reduction of a weight and a dimension for an optimized hybrid alarm valve.

Hybrid Effects of Carbon-Glass FRP Sheets in Combination with or without Concrete Beams

  • Kang, Thomas H.K.;Kim, Woosuk;Ha, Sang-Su;Choi, Dong-Uk
    • International Journal of Concrete Structures and Materials
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    • v.8 no.1
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    • pp.27-41
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    • 2014
  • The use of carbon fibers (CF) and glass fibers (GF) were combined to strengthen concrete flexural members. In this study, data of tensile tests of 94 hybrid carbon-glass FRP sheets and 47 carbon and GF rovings or sheets were thoroughly investigated in terms of tensile behavior. Based on comparisons between the rule of mixtures and test data, positive hybrid effects were identified for various (GF/CF) ratios. Unlike the rule of mixtures, the hybrid sheets with relatively low (GF/CF) ratios also produced pseudo-ductility. From the calibrated results obtained from experiments, a new analytical model for the stress-strain relationship of hybrid FRP sheets was proposed. Finally, the hybrid effects were verified by structural tests of concrete members strengthened with hybrid FRP sheets and either carbon or glass FRP sheets.