• Bulletin of the Korean Chemical Society
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• 제17권2호
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• pp.192-198
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• 1996

We present a theoretical formulation of diffusion process on solid surface based on multidimensional transition state theory (TST). Surface diffusion of single adatom results from hopping processes on corrugated potential surface and is affected by surface vibrations of surface atoms. The rate of rare events such as hopping between lattice sites can be calculated by transition state theory. In order to include the interactions of the adatom with surface vibrations, it is assumed that the coordinates of adatom are coupled to the bath of harmonic oscillators whose frequencies are those of surface phonon modes. When nearest neighbor surface atoms are considered, we can construct Hamiltonians which contain terms for interactions of adatom with surface vibrations for the well minimum and the saddle point configurations, respectively. The escape rate constants, thus the surface diffusion parameters, are obtained by normal mode analysis of the force constant matrix based on the Hamiltonian. The analysis is applied to the diffusion coefficients of W, Ir, Pt and Ta atoms on the bcc(110) plane of W in the zero-coverage limit. The results of the calculations are encouraging considering the limitations of the model considered in the study.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2011년도 추계학술발표대회
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• pp.238-240
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• 2011

수많은 건물들이 세워지고 있는 가운데 안전 역시 중요한 문제로 인식되고 있다. 본 논문은 유비쿼터스 시대에 맞추어 센서네트워크를 이용하여 건물의 화재정보를 실시간으로 감지하고 화재 발생 시 다양한 상황정보를 고려하여 대피 경로를 사용자 스마트 기기로 알려주는 상황정보 기반의 지능형 화재대피 서비스 모델 설계를 제안한다. 제안하는 서비스 모델은 센서가 실시간으로 건물 내부를 감지하고 화재 여부 및 화재지역, 연기량, 사람수 등의 상황정보를 파악하여 서버에 전송하고 서버는 전송된 정보를 분석하여 대피경로 추출 알고리즘을 이용해 최적의 대피 경로를 사용자의 스마트기기로 전송한다. 이 시스템 구현으로 건물 화재 발생시 사람들이 안전하게 대피할 수 있을 것으로 사료된다.

• 방송공학회논문지
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• 제23권3호
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• pp.403-408
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• 2018

딥 러닝의 학습을 위해서 일반적으로 많은 양의 데이터가 필요하다. 그러나 많은 양의 데이터 세트를 만드는 것은 쉽지 않기 때문에, 회전, 반전 (flipping), 필터링 (filtering) 등의 간단한 데이터 확장 (data augmentation) 기법을 통해 작은 데이터 세트를 좀 더 큰 데이터 세트로 만드는 여러 시도들이 있었다. 그러나 이러한 기법들은 이미 보유하고 있는 데이터 세트만을 이용하기 때문에 확장성에 제약을 갖는다. 이런 문제를 해결하기 위해 본고에서는 보유하고 있는 영상 데이터를 이용하여 새로운 영상 데이터를 획득하는 기술을 제안한다. 이는 기존 데이터 세트의 영상 데이터를 CBIR(Contents based image retrieval)의 쿼리로 이용하여 유사 영상들을 검색하여 획득하는 방식으로 이루어진다. 최종적으로 CBIR을 이용해 확장한 데이터를 딥 러닝으로 학습시켜 확장 전후의 성능을 비교하였다.

• 산업공학
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• 제17권1호
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• pp.22-32
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• 2004

The most complicated and difficult area in the simulation of evacuation process is the area of human behavior. However, it is generally very difficult to understand and quantify human behaviors since the factors involved vary significantly according to the types of accidents and the environment. The walking speed of passenger is especially affected by dynamic effect and list due to damage and ship motion in wave. There are various methods to get the useful data for evacuation simulation. The onboard experimental approach is one of the strongest method. This paper discusses the onboard experimental results of human mobility of passengers in evacuation from ship. To realize ship trim and heel due to maritime casuality, the passage model for experiment is made. The experiment was carried out at dynamic and static condition respectively using the ship with passage model. The result was evaluated and it will be reflected in evacuation simulation tool.

• 유통과학연구
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• 제18권2호
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• pp.5-15
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• 2020

Purpose : Today's retailers are integrating new VR technology into their new marketing strategies. Thus, this research aims to understand the role of virtual experiences in the circumstance of sales channels. Research design, data and methodology : Our model hypothesizes that five key factors determine the consumer experience of VR in the virtual retailing context: smartness, vividness, interactivity, playfulness, escape. Information access and flow are mediating variables that connect key drivers and VR satisfaction. Information access and flow then give influence to satisfaction towards VR. Satisfaction serves as a mediator that determines changes in consumer's dual intention: intention to revisit VR and intention to visit the real site. Results : According to the test results, every path except the relationship between information access and satisfaction of VR is accepted as expected at the significance level of 0.05. Conclusions : This research emphasizes the potential importance of VR and continue VR marketing research as an advent research area. Through the dual-path model, this study found that the primary function of VR is information access and flow experience. This result shows that most VR users value emotional benefits rather than rational benefits provided by VR. Finally, the satisfaction of VR can stimulate both the intention to use the VR and the intention to visit real mall.

• The Journal of Asian Finance, Economics and Business
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• 제7권7호
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• pp.519-529
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• 2020

Livelihood capitals have a clear influence on livelihood development. As for the livelihood results, it has been pointed out in the analysis of the poor households that the ability of people to escape poverty depends especially on the access to livelihood capitals. This study aims to analyze the impacts of livelihood capital on poverty among mountain people who depend on forests through human capital, social capital, natural capital, physical capital and financial capital. This research employs the model of binary regression function. Independent variables x1, x2, …, xn are targets of livelihood strategy, vulnerability context, and livelihood capitals. These variables were selected to be included in the original model with dependent variable Y as poor and non-poor households. This study surveys households living in upland areas, near forests, and households of ethnic minorities. The results show that,out of the poor household rate, nearly 4% are newly-poor households or those falling back into poverty. Therefore, the government needs to pay more attention to this disadvantaged group and implements policies such as education and training policies, credit support policies, policies to support forest development, and payment for forest environmental services in the context of emerging countries like Vietnam.

• Nuclear Engineering and Technology
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• 제51권8호
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• pp.1998-2004
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• 2019

The Multi-Physics (MP) instrument is one of 20 neutron spectrometers planned in the China Spallation Neutron Source (CSNS). This paper presents a shielding calculation for the MP instrument using Monte Carlo codes MCNPX and FLUKA. First, the neutrons that escape from the CSNS decoupled water moderator and are delivered to the beam line of the MP instrument are calculated to use as the source term of the shielding calculation. Then, to validate the calculation method based on multiple variance reduction techniques, a cross check between MCNPX and FLUKA codes is performed by comparing the calculation results of the dose rate distribution on a simplified beam line model. Finally, a complete geometry model of the MP instrument is set up, and the primary parameters for the shielding design are obtained according to the calculated dose rate map considering different worst-case scenarios.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2009년도 추계학술대회
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• pp.73-82
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• 2009

Although the Internet has been a important communication tool in modern societies, researchers did not pay attention to its' positive impacts on individual's psychological process. The Internet provides users with a unique environment such as visual isolation, non face-to-face communication, and easiness to escape from social influences. This environment enables people to take free action according to their personality and disclose themselves. From the uses and gratification perspective, the current research reveals that individuals with high extraversion are inclined to maintain social networking sites and those with high openness participate in web communities. The findings indicate that individuals' social use of the Internet may reflect their personality. To fill the research void like this, this study proposes a new research model in which well bing as well as perceived value are positively linked to satisfaction and continuance to use. The statistical results obtained by applying PLS to the valid 150 questionnaires showed that the well bing has stronger positive influence on satisfaction and continuance to use than the perceived value. Therefore, a practical implication is suggested that the web site need to be designed in a way of arousing users' well bing more strongly.

• 한국융합학회논문지
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• 제9권2호
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• pp.13-18
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• 2018

본 논문은 다층을 갖는 네트워크를 가장 효율적으로 학습하는 것은 결국 최적의 가중치 벡터의 집합을 찾아가는 과정이라는 간단한 접근 방법을 기본으로 하고 있다. 일반적인 학습 문제의 단점을 극복하기 위해 제안 모델에서는 EBP와 OVSSA의 특징들을 결합한 방법을 사용한다. 즉 EBP가 지역 최소치에 빠질 수 있는 성질을 보강하기 위해 OVSSA의 확률이론으로 빠져나갈 수 있도록 제안 방법은 각각 알고리즘의 장점만을 취하여 하나의 모델을 구성한다. 제안 알고리즘에서는 EBP에서 오류를 줄이기 위한 방법들을 에너지함수로 사용하고, 이 에너지를 OVSSA로 최소화 하는 방법을 사용하였다. 두 가지의 상이한 성질을 가지는 알고리즘이 합쳐질 수 있음을 간단한 실험 결과를 통해 확인한다.

• Journal of Information Technology Applications and Management
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• 제13권4호
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• pp.41-56
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• 2006

The real estate portal has grown into a successful e-Business model that is combined on and off line. Although IT technologies have shown rapid growth, the real estate portals have failed to satisfy the expectations of the Internet users. Based on Michael Porter's competitive forces framework, this study proposes five competitive strategies for continuing growth of the real estate portals. First, to strengthen bargaining power against supplier, buyer and potential new entrants, the real estate portals need to construct a basic network that is cost efficient and maintains real estate goods and makes profits by collaborative deals. Second, strengthen brand value and endeavor to escape from dependency on the Internet portals. Third, develop services to consider changed circumstances and give a lot of sources to make profit to real estate agencies. Fourth, concentrate on marketing to draw in the Internet users and adapt strategies that have been successful in other fields. Finally, real estate fields can seek out ideas for developing new business models from other successful e-Business models and should benchmark them to reduce expenses to a minimum and increase benefits to a maximum.