• 대한전자공학회논문지TC
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• 제48권3호
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• pp.19-27
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• 2011

광 네트워크 기술의 발달로 인해 오늘날 대부분의 네트워크는 수십 Gb/s를 지원한다. UDT(UDP-based Data Transfer protocol)는 대역폭과 지연시간이 큰 네트워크 환경에서 대용량 데이터 전송을 위한 프로토콜이다. 그러나 UDT는 고정된 sync-interval(0.01초) 간격으로 주기적인 rate control을 실행한다. 네트워크 트래픽 상태의 변화가 심한 환경에서는 sync-interval 동안 가용 대역폭을 충분히 활용하지 못하는 문제점이 발생한다. 본 논문은 sync-interval 구간에서 네트워크 트래픽 상태에 적응적인 rate control 기법을 제안한다. 네트워크 트래픽 상태는 RTT 변화를 바탕으로 판단한다. 제안 기법은 네트워크 상태를 4개의 구간으로 설정하여 패킷 sending period를 조절함으로써 rate control을 수행한다. 시뮬레이션 결과를 통하여 기존 UDT에 비해 throughput 과 안정성이 향상되었음을 보였다.

• 전기전자학회논문지
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• 제22권3호
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• pp.862-865
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• 2018

The proposed scheme minimizes the Idle time under the residual energy of the sensor node to adjust the Sleep-Wakeup period and minimize unnecessary energy consumption. It is The proposed scheme minimizes the Idle time under the residual energy of the sensor node to adjust the Sleep-Wakeup period and minimize unnecessary energy consumption. It is an important process to control the Application Packet Framework including the PHY and the MAC layer at each node's Idle time with the Idle time mechanism state before the proposed function is executed. The Current Control Level of the Report Attribute is fixed at one sending / receiving node where power consumption can occur, by changing Sleep-Wakeup time, the low power consumption efficiency was improved while satisfying the transmission requirement of the given delay time constraint.

• Journal of Communications and Networks
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• 제15권2호
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• pp.153-163
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• 2013

In recent years, more and more researches have been focusing on trust management of vehicle ad-hoc networks (VANETs) for improving the safety of vehicles. However, in these researches, little attention has been paid to the location privacy due to the natural conflict between trust and anonymity, which is the basic protection of privacy. Although traffic safety remains the most crucial issue in VANETs, location privacy can be just as important for drivers, and neither can be ignored. In this paper, we propose a beacon-based trust management system, called BTM, that aims to thwart internal attackers from sending false messages in privacy-enhanced VANETs. To evaluate the reliability and performance of the proposed system, we conducted a set of simulations under alteration attacks, bogus message attacks, and message suppression attacks. The simulation results show that the proposed system is highly resilient to adversarial attacks, whether it is under a fixed silent period or random silent period location privacy-enhancement scheme.

• 수산경영론집
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• 제43권3호
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• pp.1-22
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• 2012

This study is to survey the Japanese investigations for Korean sea during Meiji period. Meiji government was eager to develop new fishing ground to provide the marine products to their people, to offer the job for their people and to accumulate the starting capital. They found that the Korean sea was abundant in shark, sea cucumber and ear shell. These products were valuable for Chinese foods. From 1870's, Japan Navy investigated Korean sea for military purpose and subsequently for fishery. The first investigation for Korean maritime products was The Circumstances for Catching Fish in Korean Sea by Sekizawa Akikiyo in 1893. He was the most famous specialist in fishery and insisted that Japanese fishermen must go to Korean sea and catch fishes. Meiji government accepted his opinion and pushed the policy sending fishermen to Korean sea. Meiji government enlarged the investigations and backed up the activities of fisherman and the organization for fishery in Korean sea. Especially, the investigations by The Association for Korean Sea Fishery were repeated and detailed(1897~1900). The Association intervened the conflicts between Korean and Japanese fishermen. At the same time, The Association investigated the attitudes of Korean people to Japanese. The Guidelines for Fishery in Korean Sea by Kuzuu Syuzo was also very detail, especially in the kinds of fishes in Korean sea. These investigations were supported by Meiji government or organizations helped by government.

• 한국보건간호학회지
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• 제3권2호
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• pp.143-156
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• 1989

This study was done in order to analyze the factors which influenced the performance level of urban family planning health personnels' task. Interview survey was done during the period May, 1989. Interviewee were 130 family planning health personnels among total of 140 family planning health personnels in Seoul metropolitan city area. The internal consistency reliability was tested by Cronbach’s Alpha and the construct validity of the survey tool was tested by Factor analysis. Multiple stepwise regression analysis was used to identify major factors influenced to perform family planning health personnels' task. The results of this study were summarized as follows: 1. The internal consistency reliability was high and very significant (Cronbach's Alphs=0.8445, p<0.0000). 2. The construct validity was high and very significant. This analysis was contained 5 factors; registering and keeping of eligible woman records, health educating for FP & MCH, referral for vasectomy and tubal ligation and loop, supplying contraceptive appliances, sending moved-out eligible woman records. 3. Among a total of 15 contents of their functions recording of daily report and monthly report (76.2%), classifying and keeping of records(66.2%), registering of eligible woman records(60.85ti), distribution of leaflets and pamplets(54.6%), counselling & supervision about family planning(53.8%) were actively performed. Sending moved-out eligible woman records(60.8%), health education for community people(49.2%), referring contraceptors' side-effects were poorly performed. 4. The factors which influenced the performance level of urban family planning health personnels' function were age, marital status, educational level, certification, number of residents, number of eligible women, job car-eer, work responsibility, job satisfaction knowledge, position, cooperation of community people, cooperation of Dong Office, cooperation of Health Center. These 14 variables were able to explain job function from 21.4% of follow-up care of contraceptor to 9.1% of classifying & keeping of eligible woman records.

• International Journal of Quality Innovation
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• 제10권2호
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• pp.43-56
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• 2009

Many companies are trying to acquire innovative technologies and relevant knowledge by sending R&D work overseas. Although recent research has been focusing on the aspects that motivate MNCs to establish offshore R&D facilities, such as cost reduction and market expansion, little is known about external or circumstantial factors influencing the performance of global R&D activities. Searching for enhancers of offshore R&D facilities, we investigated the relationships between the performance of offshore R&D and the technological capabilities of a parent company, its home country, and its R&D hosting country. Both patent data of ED and the ED R&D scoreboard of 134 overseas R&D labs from 46 MNCs, dating from the period of 2003 to 2005, are used in the analysis. The same time period is applied in calculating the RTA of each country. Regression analysis results support our main hypothesis that the technological capabilities of the parent company and the hosting country positively affect the performance of overseas R&D.

• 통상정보연구
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• 제12권3호
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• pp.335-359
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• 2010

The purpose of this study is to interpret the articles revision of the 2009 ISC(Cargo) compared to the 1982. The result of this study is summarized as followings: 1) the 'clause' attached to article in 1982 ISC(Cargo) was deleted in the revision of 2009 ISC(Cargo). 2) 2009 ISC(Cargo) is characterized as the marine insurance firms' acceptance of new environment change, limitation in causation and subject-matter insured, expansion of insurance period, and limited revision. 3) The assured has a large range of choice in 2009 ISC(Cargo) even though both 1982 ISqCargo) and 2009 ISC(Cargo) would be existed further. 4) There are few studies which have a focus on the impact of the relationship between responsibility of the insurer and opportunity of the assured on rate of premium. In the future, the studies on clauses, relationship among clauses, relationship between clause and rate of premium are needed in the 2009 ICC(Air), 2009 IWC(Air Cargo), 2009 ISC(Air Cargo), 2009 IWC(sending by post) et al.

• 무역상무연구
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• 제42권
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• pp.89-107
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• 2009

The latest UCP, Uniform Customs and Practice for Documentary Credits, 2007 Revision, ICC Publication No.600 has been adopted by most banks in the world since July 1, 2007. This work intends to study some points for practical attention of UCP 600 in the field of examining documents and defining some words. Some points for practical attention of UCP 600 in the field of examining documents include the period for examining documents, the conflict with data in the documents, and the fulfilling the function of documents. Some points for practical attention of UCP 600 in the field of defining some words include the complying presentation, negotiation, and nominated banks. Furthermore, this work studies some points for practical attention of UCP 600 in relation to the nomination and the missing in the course of sending documents.

• 경영과정보연구
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• 제7권
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• pp.341-363
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• 2001

The purpose of industry-education cooperation field training is improving students' abilities & skills by working at industrial companies and experiencing how to apply their school knowledge to a real work for some period of time. The followings are recommendable ways of industry-education cooperation field training management to improve the students' adaptability of industrial companies with the most effectiveness (1) Prior to everything, setting the industry-education cooperation field training program to have extreme efficient and managing it with exhaustiveness & intensiveness is necessary. (2) Before sending students to industrial companies for education, the committee must make an inspection of industrial companies to decide whether they have the fine educational value. (3) To assign eve student to proper industrial companies, school authorities must survey the aptitude, desire and ability of each students and peculiarities of each industrial companies. (4) Figure out a way to increase the students' adaptability with a highest degree. (5) To help the employment of students who finished the industry-education cooperation field training with on admirable record, the committee must discuss that matter with industrial companies & students.

• 한국의사학회지
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• 제28권2호
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• pp.59-72
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• 2015

Simyak (審藥) was a government officer to lowest, but it was appointed and dispatched directly by officials from the central government. Simyak played a role in mediating between the provincial and central health care. Therefore, understanding Simyak is necessarily required in the researches on the local health care in Joseon dynasty. Preceding researches of Simyak only have contained superficial information causing many errors. The purpose of this paper is to understand Simyak correctly through the historical literature review. The author found the following facts in this study. First, Simyak was succeeded to the government officer of Uihakgyoyou (醫學敎諭) in the previous period. Second, through the change of the name of Simyak, it can be presumed that the main task of Simyak was changed from the role in local medical education to the officer sending the herbs to the central government. Third, in the later Joseon dynasty Simyak was monopolized by some families just like any other medical officials. Fourth, Yangdowollyengui (兩都月令醫) and Tongyeongguryogwan (統營救療官) can also be put in the category of Simyak.