• Journal of Navigation and Port Research
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• v.39 no.6
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• pp.515-521
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• 2015

The purpose of this study was to analyze the weights of obstacle factors against mutual access of towed trailers of car-ferry between South Korea and China using Fuzzy-AHP. To this end, factors were first selected through literature research and finally selected through in-depth interviews with a group of experts in cargoes who are currently in car-ferry companies. Selected high rank obstacle factors included unstable service provision, limited policy support, and additional costs being incurred and among them, unstable service provision was identified as the most serious obstacle factor through analysis. Eleven measurement variables selected include insufficient supply of container yard, trailer insurance and management issues, insufficient special equipment, insufficient specialized manpower, limited input service courses, insufficient marketing and public relations strategies, and increasing transportation costs and among them, increasing equipment returning costs due to unbalanced cargo gathering were identified as the most serious obstacle factor through analysis followed by limited input service courses, insufficient special equipment, delays in procedures, and occurrence of additional procedures in order of precedence.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.8
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• pp.1843-1848
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• 2010

The Key exchange protocols are very crucial tools to provide the secure communication in the broadband satellite access network. They should be required to satisfy various requirements such as security, Key confirmation, and Key freshness. In this paper, we propose Two authenticated key exchange protocols Two Pass EKE-E(Encrypted Key Exchange-Efficient) and Two Pass EKE-S(Encrypted Key Exchange-Secure) are introduced. A basic idea of the protocols is that a password can be represented by modular addition N, and the number of possible modular addition N representing the password is $2^N$ The Two Pass EKE-E is secure against the attacks including main-in-the-middle attack and off-line dictionary attack, and the performance is excellent so as beyond to comparison with other authenticated key exchange protocols. The Two Pass EKE-S is a slight modification of the Two Pass EKE-E. The Two Pass EKE-S provides computational in feasibility for learning the password without having performed off line dictionary attack while preserving the performance of the Two Pass EKE-E.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.10a
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• pp.79-81
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• 2012

The concern of Global warming and greenhouse gas emission has been issuing so many countries are trying to establish environmental friendly logistics policies. With this trend, several technical and operational methods are developed to realize green logistics way. In Korea, government promoted converting LNG cargo vehicles and constructed LNG station at Dajeon, Pohang, Gwangyang, Incheon, and Donghae as a national project. In spite of economic and environmental advantages, this project was not successful enough, even the project was cancelled. So, this paper seeks the reason why the project was failed and find if there were enough capacity and numbers of LNG stations, then analyze the problem.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.5829-5835
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• 2015

This paper investigates the impact of corporate governance structure on the firm's debt costs under different governance environments. We find that after the 2008 banking crisis, family firms with controlling shareholders benefit from lower debt cost through the strong control rights of dominating large shareholders, compared with the firms with diversified minority-shareholders. Foreign investors are related statistically to the higher cost of debt. Before the 2008 banking crisis, cash flows and growth potentials are positively associated with the firm's cost of debt.

• Journal of Korea Water Resources Association
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• v.37 no.10
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• pp.789-798
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• 2004

Conjunctive use of surface and ground water is emerging as an alternative to resolve water shortage problems caused by drought or overpopulation. The region whose water supply depends on a single source has high risk of emergency situations, and may need to consider conjunctive use to overcome its weakness. Conjunctive use also can be a realistic and effective solution when additional or new water resources are to be developed. This paper presents a new methodology for managing surface and ground water resources with the aim of supplying water in a sustainable way. The developed method encompasses procedures to assess site suitability for conjunctive use, to devise water supply scenarios based on drought analysis, and to quantify the amount of water attained. It is believed that the systematic and objective features of the developed method enable it to be a useful supportive tool for water management planning and decision-making.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4251-4259
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• 2010

This study investigates the needs of cruise tourists for building customer oriented ubiquitous tourism services. Through the field survey, the relationship between cruise tourism motivations and ubiquitous cruise services were analyzed. In this study, cruise tourism motivations mean destination attraction, family friendship, socialization, education/novelty and escape from daily routine. And ubiquitous cruise services are consists of boarding service, security service, safety service, customization service, and payment services. The results are as follows; cruise tourists with more socialization motivation get more use intention of ubiquitous payment service; cruise tourists with more destination attraction have more use intention of ubiquitous customization service.

• Journal of the Institute of Convergence Signal Processing
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• v.12 no.2
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• pp.107-112
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• 2011

Several developed countries have been developing their own satellite navigation systems, such as Europe's Galileo, China's BEIDOU, and Japan's QZSS, to cope with clock errors and signal vulnerabilities of GPS. In addition, modernization of Loran, eLoran, for GPS backup has been conducted. In Korea, a dependent navigation system has been required and for GPS backup, the need for utilization of time synchronization infrastructure through the modernization of Loran has been raised. Loran signal uses 100Khz groundwave. A significant factor limiting the ranging accuracy of the Loran signal is the ASF arising from the fact that the groundwave signal is likely to propagate over paths of varying conductivity and topography. Thus, an ASF compensation method is very important for Loran and eLoran navigation. This paper introduces the propagation delay model and then compares and analyzes the estimations from the propagation delay model and measured ASFs.

• Korean Journal of Construction Engineering and Management
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• v.21 no.5
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• pp.38-45
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• 2020

Presently, safety management of facilities is conducted as a site-oriented safety inspection, but depending on the facilities, there are difficulties in access to the site, and the cost and time of inspection are inefficient due to excessive reliance on human resources. Therefore, the necessity of sensor-based safety management is being raised to ensure the safety of the facility at all times, and various studies on sensor safety management are being conducted, but the research on verification of practicality is still insufficient. Therefore, the improvement points were presented through analysis of domestic and international studies, and additional processes for setting sensor attachment location and threshold were derived by analyzing the H city sensor safety management process, and practicality of sensor safety management was verified through sensor data measurement values. It is expected that efficient, sensor-based facility safety management will be possible if clear criteria and ongoing practicality verification for the additional processes presented in this study should be carried out in the future.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.177-177
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• 2017

최근 ADCP 등 첨단장비를 활용한 유량 및 하상측정, 각종 하천기본계획 수립 시 확보되는 횡단측정 자료, 식생 및 서식처 등 하천환경과 생태자료, 드론 등을 활용한 영상자료 등 방대한 하천 정보가 확보되고 있으며, 다기능보 등 다양한 하천구조물 및 친수구역이 증가하는 등 이전과 비교하여 괄목할만한 수준으로 정보의 양이 증가하고 있다. 이에 따라 다양한 하천정보를 체계적으로 저장, 관리, 공유하기 위하여 표준화된 데이터 모델(Data Model)의 수립이 필요하다. 하천 정보의 경우 하천 시설물, 하천 단면측량 자료, 하천 시계열 측정 자료 등이 특정 하천을 중심으로 관리되는 반면, 기존 데이터 모델 연구에서는 특정 주제도에 기반하여 하천 정보가 레이어 형식으로 제공되어 상호 연계되지 않아 하천 정보의 효율적 관리측면에서 적합하지 않았다. 또한 신규 정보를 추가 시 기존 데이터 모델의 과다한 수정이 필요하고, 기존의 데이터 모델의 경우 표준화되지 않아 활용성이 매우 낮고, 유역중심으로 구성되어 특정 조건에 해당되는 하천 정보 검색이 어려운 단점이 존재하였다. 본 연구에서는 기존의 주제도 및 레이어 형식으로 구성되어 있던 데이터 모델 형식에서 벗어나 하천흐름선을 기준으로 데이터모델을 구축하는 방안을 제시하였으며, 하천흐름선과 하천 시설물, 단면 측량 자료, 계측 자료를 순차적으로 수용하고, 기존에 존재하지 않던 하천 정보의 추가 시 기존 데이터 모델의 형식을 수정하지 않고 유연하게 대응할 수 있는 관계형 데이터 모델을 구상하였다. 또한, 하천과 유역의 논리적 저장방안 고려하여 한 개의 하천을 다수의 세그먼트(Reach)로 구분하여 코드(Reach Code)를 부여하는 방안을 제시하였으며, 구상한 데이터모델을 통하여 국가하천과 지방하천 등 유역의 다양성을 포함하는 한강권역의 섬강유역을 시범하천으로 구축하였다. 제시된 하천 정보 데이터 모델을 활용하여 DB를 구축한다면 하천망을 기준으로 하천 정보가 저장되고, 기존의 유역단위의 하천 정보 제공 방식에서 하천과 유역을 모두 포함하여 검색 가능한 시스템을 구축하여 하천 정보의 관리와 제공이 수월해질 것으로 기대된다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.876-879
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• 2009

As performance and feature set of mobile devices are getting better, the scope of things for which they can be used is also getting widened. More than simply browsing information using mobile web, now these devices can interact with users. It requires various features to manage a web site; supporting full-browsing alone is not enough since there are problems such as processing speed, user interface restriction. However, using mobile devices to manage a web site has its own merits since the can be used without restriction of time and location. In this paper, we introduce a mobile web site administration software that provides both online and offline features. It supports CRUD (Create, Read, Update, Delete) operations for news and users. These operations can be executed both offline and online. A user can do most of things offline; It connects to online only when it's absolutely necessary and does those in batch mode.