• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.318-321
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• 2000

이 연구는 정보통신기기 수출량에 관해 하향식(Top-down) 방법에 기초한 예측 모형을 제시한다. 하향식방법은 전체 수출량과 전체를 구성하는 개별 항목간에 계층적 관계를 바탕으로 순차적으로 예측을 수행하는 방법이다. 전체와 개별 항목간에 관계는 데이터의 시계열 특성과 데이터에 영향을 주는 요인들에 의해서 만들어진다. 이러한 관계를 바탕으로 하는 하향식 예측은 전체 수출량을 먼저 예측한 후 이 예측치를 바탕으로 하여 개별 항목에 대한 예측을 수행한다. 하지만 하향식 방법은 가장 아래 계층의 예측치를 산출하기 위해 필요한 것이며 최종 예측치는 가장 마지막 계층에서부터 예측 데이터를 합산해서 얻을 수 있다. 결국 하향식 예측 방법은 전체와 개별 항목 사이에 상관관계가 높고 계층화되어 있는 구조에 적합하다. 이 예측 대상이 되는 정보통신기기 수출량에 대한 적용 사례를 살펴보자. 계층 구조를 보면 정보통신기기 전체 수출량과 전체를 구성하는 개별 항목으로 정보통신기기 분류별(유선기기, 무선기기, 방송기기, 정보기기, 기타부품기기)과 국가별(미국, 일본, 중국 등 7 개국)로 나뉘어진다. 다시 이 아래 계층으로는 국가와 정보통신기기의 행렬 구조(예: 미국-유선, 일본-부품 등)에 의해 35 개로 나뉘어진다. 각 단계별 예측 방법을 보면 전체 수출량은 시계열 특성과 거시적 변수를 반영한 시계열 모형, 그 아래 계층인 국가별과 분류별 모형에는 전체 수출량 시계열 특성과 국가별과 분류별에 영향을 주는 관련 변수를 반영한 회귀모형 그리고 행렬 구조에 대한 예측은 상위 계층의 시계열 특성과 행렬구조 데이터의 계절성이 반영된 다중 회귀모형을 이용하였다.ndex, mobile user′s will first be classified by their traffic volume, and then calculate the average tariffs per minute of each group of users, and lastly weight-average those tariffs per minute. And finally, this paper shows the mobile tariff index by considering those averaged tariffs and the carriers′ market shares to reflect the contribution of individual carriers and the users′ traffic volume.완화될 수 있다. 즉, 봉지를 씌웅으로서 봉지 내의 대기 환경이 외기보다 안정적으로 유지되고 직사광선이나 농약 및 마찰로부터 과실을 보호해 주기에 동녹이 어느 정도 방지될 수 있는 것이다. 그러나 기존의 황금배봉지는 동녹의 정도를 완화시킬 뿐 완전히 방지할 수 없었으며, 봉지를 적 용한 재배조건에서의 동녹발생 기구를 정확히 이해하지 못했었기에 효과적으로 봉지의 기능 을 개선하는 것이 불가능하였다. 과설의 미려도는 과실의 맛과 함께 그 가치를 결정짓는 중요한 물성으로서 우리나라 황 금배 재배환경과 특성에 알맞은 배봉지의 제작이 선결될 때, 배 품질의 향상, 안정된 공급이 가능하게 될 것이며 아울러 농가의 수업증대와 수출 경쟁력 강화가 이루어질 수 있을 것으로 판단된다. 이러한 측면에서 황금배 재배농가가 당면한 동녹발생의 문제점을 신속한 해결 을

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.5
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• pp.143-149
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• 2016

Recent accidents caused by toxic chemicals and the social problems caused by frequent. As of 2010, there are more than 100,000 types of deadly toxic chemicals being distributed throughout Korea, and severely intoxicated patients along with an enormous number of patients can be induced at the time of an accident involving deadly toxic chemicals. Internationally, the seriousness of large-scale disasters due to a NBC disaster (nuclear, biologic and chemical disaster) is being highlighted as well. So, we obtain the information of the RFID tag attached to a glass bottle with containing the toxic chemical to transfer the data to the smart device has been studied a system that can monitor the status of the toxic chemical in real time. The proposed system is the information was sent to the main system using a zigbee communication by recognizing the tag vial containing the toxic chemical with the 13.56MHz bandwidths good permeability. User may check the information in real time by utilizing the smart device. However, the error of the system for managing the toxic chemical generates a result that can not be predicted. Failure of the system was detecting the error by using a comparator as this can cause an error. And the detected error proposed a duplex system so that they do not affect the overall system.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.10
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• pp.137-147
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• 2007

In the host-based Mobile IPv6, a mobile node is responsible for doing the signaling to its home agent to enable session continuity as it moves between subnets. To remove the mobile node's signalling processing load, the network-based Mobile IPv6 has been proposed recently. It allows session continuity for a mobile node without its involvement in mobility management. The proxy mobility agent in the network performs the signaling and does the mobility management on behalf of the mobile node. However, to make secure communications for a mobile node, security mechanisms against diverse attacks should be adopted. To do this, first of all security threats to the network-based Mobile IPv6 should be also identified and analyzed. Potential attack objectives may be to consume network services at the cost of a legitimate mobile node and, eavesdropping and fabrication of user traffic through interception of a mobile node's communications. This paper identifies and discusses security threats to the network-based Mobile IPv6 in details. The results of threats analysis are limited to threats that are peculiar to the network-based Mobile IPv6 except threats to IPv6 in general.

• Journal of Engineering Education Research
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• v.10 no.3
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• pp.79-92
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• 2007

To enhance the excellence, effectiveness and economical efficiency in the learning process, we implement a hybrid educational system for engineering experiments where web-based virtual laboratory systems and distance education systems are properly integrated. In the first stage, we designed client/server distributed environment and developed web-based virtual laboratory systems for digital systems and electrical/electronic circuit experiments. The proposed virtual laboratory systems are composed of four important sessions and their management system: concept learning session, virtual experiment session, assessment session. With the aid of the management system every session is organically tied up together to achieve maximum learning efficiency. In the second stage, we have implemented efficient and cost-effective distant laboratory systems for practicing electric/electronic circuits, which can be used to eliminate the lack of reality occurred during virtual laboratory session. The use of simple and user-friendly design allows a large number of people to access our distant laboratory systems easily. Thus, self-guided advanced training is available even if a lot of expensive equipment will not be provided in the on-campus laboratories. The proposed virtual/distant laboratory systems can be used in stand-alone fashion, but to enhance learning efficiency we integrated them and developed a hybrid educational system for engineering experiments. Our hybrid education system provides the learners with interactive learning environment and a new approach for the delivery of engineering experiments.

• Journal of the Korean Institute of Gas
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• v.23 no.6
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• pp.39-60
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• 2019

Korea Gas Safety Corporation is developing consequence analysis system for combustible materials release events to enhance risk assessment technology and its efficiency. Unlike general consequence analysis programs, the final consequence area was implemented through ETA analysis based on API-581 standard, and a convenient user interface was constructed based on HTML5-based responsive web technology. In addition, a phase equilibrium module using third-order state equations (such as Peng-Robinson, SRK, and RK) and fugecity was implemented to analyze the mixture quality. Also. using the consequence analysis algorithm introduced in CCPS books and TNO Yellow Book, we developed material leak analysis module, fireball, pool fire, jet fire, flash fire, and vapor cloud explosion consequence assessment module. In addition, the conditions for calculating the safety distance were prepared with using the control values in the EIGA standard, PAC, and Bevi Reference Book.

• Journal of Korea Multimedia Society
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• v.9 no.10
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• pp.1332-1343
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• 2006

This paper proposes an educational community service system that manages information of good quality intensively without overlapping, and that provides an effective searching function by using a personal community with many user layers. This system raises the efficiency of searching and management by using Metadata and Category. It is a self-leading educational community system that brings merits into relief and improves weak points. We constructed an autogenous Blog chain service as a tool which verifies this system, which is called 'EduLOG(Educational Blog) service' Especially we extracted Metadata suitable for this service, which is on the basis of worldfamous Dublin Core Metadata. And we made a new category on the basis of categories which were proposed by some educational community sites and public educational authorities, and we applied it to this system. To ascertain whether this service system provide adequate function or not, we made a questionnaire on the basis of the appraisal table in websites, and evaluated it at the request of experts. In view of the results so far achieved, it returned good scores (above 3.5/5.0) in accuracy of evaluation, low-end reappearance ratio, easiness of registering and approaching information, and intensive management of a categorical information, confirming the efficiency of the ECSS system. Therefore we believe firmly that the ECSS system will play a efficient information storing and searching roles in the near future.

• Journal of Global Scholars of Marketing Science
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• v.15 no.1
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• pp.105-120
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• 2005

The research regarding the important attribute which gives an effect to golf club membership purchase. 1990's as the golf boom as percentage shows the rapid increase of the golf course visitor and it grows, from 2001 are passing over ten million people golf course visitors. When purchasing golf club membership, it is important from the research which it sees the attributes which it thinks probably are what, it grasped and the scope of research did Seoul and the metropolitan area golf user in the object and it executed an empirical.analysis. In order to raise the reality and a reliability of research also it executed the collection and a Question investigation and a empirical analysis of various statistical data. The result of research a frequency analysis, descriptive analysis, factor analysis, multiple regression analysis and a correspondence analysis used the SPSS/PC+ 10.0 which and is a statistics package program. The results show that four dimensions of image were derived from 14 important attributes, using a factor analysis. A correspondence analysis indicates that statistically significant relationships existed between some of Golf club membership factors with respect to the demographic variables of income and Golf frequency. A multiple regression analyses also indicate that most of Golf club membership factors had great impacts on visitors' recommend.

• Knowledge Management Research
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• v.19 no.1
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• pp.59-77
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• 2018

The tourism industry is now changing to smart tourism, which maximizes tourists' overall tourism experience with the use of advanced mobile technologies and emphasizes the utilization of tourism information. Despite the quantitative expansion of the tourism industry, there is a lack of academic and practical discussion on tourism safety. Especially, in the context of walking tourism, tourists are more likely to be exposed to natural or social disasters and emergencies. Therefore, it is necessary to build a system that can provide walking tourists with safety information not only on dangerous factors which are anticipated to be confronted during a walking trip in advance but also on specific dangers in real time. Under the circumstances, this study seeks to identify the types of tourism safety information that can be offered by using publicly available open data, drawing on the safety information framework on the walking tourism that is presented in Choi et al. (2017)'s study. More specifically, this study focuses on the use of open data which is provided by the Korean government. Furthermore, this study verifies the types of safety information that are most urgently needed in walking travel situations. Specifically, this study aims to derive the importance and priority of each type of safety information for a walking trip by applying the analytic hierarchy process (AHP) analysis. For this, we collected 35 questionnaires from walking tour operators (practitioners) and walking tourists. The main results are as follows. First, natural disaster information is the most important factor in the top-level factor of safety information for walking tourists, followed by social disaster, life safety, and exhibition (security crisis) information. Second, information on natural disasters, environmental pollution, and weather is considered to be important at the sub-level factor. Lastly, the noteworthy result of this study is that the importance of each type of safety information varies depending on the walking tour operators (practitioners) and the walking tourists. That is, there is a recognition difference between the operator (practitioner) and the user in the importance and priority of the safety information of the walking trip. Therefore, it is necessary to develop policies and services reflecting the opinions of potential users when providing safety information so that the most importantly recognized information can be provided first.

• Knowledge Management Research
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• v.21 no.3
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• pp.27-44
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• 2020

In order to solve the user's information overload problem, recommender systems infer users' preferences and suggest items that match them. The collaborative filtering (CF), the most successful recommendation algorithm, has been improving performance until recently and applied to various business domains. Visual information, such as book covers, could influence consumers' purchase decision making. However, CF-based recommender systems have rarely considered for visual information. In this study, we propose VizNCS, a CF-based deep learning model that uses visual information as additional information. VizNCS consists of two phases. In the first phase, we build convolutional neural networks (CNN) to extract visual features from image data. In the second phase, we supply the visual features to the NCF model that is known to easy to extend to other information among the deep learning-based recommendation systems. As the results of the performance comparison experiments, VizNCS showed higher performance than the vanilla NCF. We also conducted an additional experiment to see if the visual information affects differently depending on the product category. The result enables us to identify which categories were affected and which were not. We expect VizNCS to improve the recommender system performance and expand the recommender system's data source to visual information.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.5
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• pp.92-102
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• 2016

While there have many completions of large parks recently under development, there has been a dearth of quality assessments. Studies focused on post-evaluation have been made to resolve this, but most of these are biased toward user satisfaction after completion and therefore behaviour analysis has limitations on solving problemsduring the actual design implementation processes. Therefore, this study examined the internal phenomenon and structure of the implementation process of design competition through the ground theory and microscopic independent perspective. As a result, maintaining the identity and differentiation of parks derived from the preserved design competition scheme contributed greatly to completeness and satisfaction. Outcomes were mainly caused by the trust of public officials as the ordering organization, the will of policy decision-makers, and the competence of operational enterprises, etc. Negative factors such as undermining the whole concept of the park and landscape occurred as external pressure and related subjects intruded on change design factors due to variations in social conditions. Additionally, illogical construction processes occurred, such as a reinvestigation of the budget for restoration after damaging on original landscape. There have been needs for the improvement of the work processing system. On balance, an interventional role is very important in the park construction process, especially the PA and operation committee in terms of maintaining the basic direction, landscape design supervision for detailed designs, and expert construction management on LA in terms of rational work management in the field. The study, using the microscopic perspective of the designer and ground theory, deliver significant meaning as an early study by suggesting alternative methods for the after-evaluation of large parks and structurally looking into main influence factors driven during the construction process.