• Journal of the Korea Society of Computer and Information
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• v.14 no.10
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• pp.101-110
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• 2009

The 6LoWPAN(IPv6 Low-power Wireless Personal Area Network) performs IPv6 header compression, TCP/UDP/IGMP header compression, packet fragmentation and re-assemble to transmit IPv6 packet over IEEE 802,15.4 MAC/PHY. However, from the point of view of security. It has the existing security threats issued by IP packet fragmenting and reassembling, and new security threats issued by 6LoWPAN packet fragmenting and reassembling would be introduced additionally. If fragmented packets are retransmitted by replay attacks frequently, sensor nodes will be confronted with the communication disruption. This paper analysis security threats introduced by 6LoWPAN fragmenting and reassembling, and proposes a re-transmission mechanism that could minimize re-transmission to be issued by replay attacks. Re-transmission procedure and fragmented packet structure based on the 6LoWPAN standard(RFC4944) are designed. We estimate also re-transmission delay of the proposed mechanism. The mechanism utilizes timestamp, nonce, and checksum to protect replay attacks. It could minimize reassemble buffer overflow, waste of computing resource, node rebooting etc., by removing packet fragmentation and reassemble unnecessary.

• Genomics & Informatics
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• v.6 no.2
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• pp.87-90
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• 2008

During the last four years, the pyrosequencing-based 454 platform has rapidly displaced the traditional Sanger sequencing method due to its high throughput and cost effectiveness. Meanwhile, the Sanger sequencing methodology still provides the longest reads, and paired-end sequencing that is based on that chemistry offers an opportunity to ensure accurate assembly results. In this report, we describe an optimized approach for hybrid de novo genome assembly using pyrosequencing data and varying amounts of Sanger-type reads. 454 platform-derived contigs can be used as single non-breakable virtual reads or converted to simpler contigs that consist of editable, overlapping pseudoreads. These modified contigs maintain their integrity at the first jumpstarting assembly stage and are edited by fragmenting and rejoining. Pre-existing assembly software then can be applied for mixed assembly with 454-derived data and Sanger reads. An effective method for identifying genomic differences between reference and sample sequences in whole-genome resequencing procedures also is suggested.

• Journal of the military operations research society of Korea
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• v.3 no.1
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• pp.97-107
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• 1977

This report examines several models, such as random or area bombardment, salvo fire and pattern fire, for the computation of target coverage when multiple rounds are fired at a target. Fractional kill of a fragment sensitive target by a fragmenting projectile as a function of the number of rounds fired is compared for two salvo fire models. The first is a standard salvo fire model in which N rounds are fired at the same aim point, in the second model single kill probability is computed for a fragment sensitive target and then fractional kill from the firing of N rounds is computed according to the assumption that the effects of each round are independent. Because the method of solution becomes very laborious for large patterns, this report gives a method only for the case of evaluating the effectiveness of stick and trianglar pattern fire. The need for the sophisticated and complicated target coverage models is demonstrated by the results of computations performed in this report.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.10a
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• pp.158-161
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• 2016

모바일 기기의 발전과 함께 다양한 어플리케이션의 기능이 제공되면서 전력에 대해 효율적인 관리가 필요해졌다. 효율적인 관리를 위하여 모바일 디바이스에서의 전력 소모 원인을 분석해야만 한다. 그러나 기존 연구에서 사용되었던 안드로이드 프레임워크의 수정을 통한 전력 분석 방법은 개발에 대한 용이성이 낮은 단점이 존재하고, 프로파일링을 통한 전력 분석 방법은 각 디바이스 모델에 의존적인 단점이 존재한다. 따라서 본 논문에서는 기존 연구들의 문제점을 개선하기 위해서 안드로이드 프레임워크를 수정하지 않고 획득할 수 있는 프로세스와 서비스의 목록 정보를 통해 어플리케이션이 소모하는 전력에 대한 분석을 제안한다. 본 논문에서 제안하는 방법을 GPS를 사용하는 어플리케이션을 분석하기 위해서 적용해보았다. 이를 통해 사용자는 측정된 전력과 함께 해당 전력을 사용하고 있는 프로세스 및 서비스 목록을 확인 할 수 있다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.01a
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• pp.165-167
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• 2021

본 논문은 노약자와 장애인의 편의를 도모하기 위하여 주기적으로 약을 복용해야하는 시간을 알려주는 시스템이다. 무게 센서를 사용하여 7일간 복용해야 하는 알약들의 전체 무게를 측정하고, 사용자가 알약을 복용하면 줄어든 알약의 무게를 다시 측정하여 복용 여부를 판단하는 시스템이다. 또한 알약을 복용하지 않은 사용자에게 이를 알려주기 위해 설정된 특정 시간에 다시 알려주는 작업을 수행하도록 구성하였다. 본 논문에서는 시뮬레이션을 통하여 이와 같은 시스템의 작업 수행 과정을 세분화하여 보여줌으로써 사용자들이 잊지 않고 약을 복용하는 것을 도와주고자 한다.

• Journal of Digital Convergence
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• v.11 no.8
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• pp.31-39
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• 2013

Recently, integration between social media and the industry has been expended, and as the usage of Internet through various smart devices of not only the existing PC but also smart phone, tablet PC and so on, a lot of unstructured data has occurred, leading to increased interest on big data system. According to the institutes which specialize in market research, the data amount is predicted to increase by 9 folds in the next 5 years when compared to the present, and the big data market is also expected to grow bigger. This dissertation evaluates the efficiency test of big data through analysis on the requirements by identifying and fragmenting the items of efficiency quality evaluation that big data should be equipped with.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05e
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• pp.108-111
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• 2003

The main objective of this paper is to module design and pressure relief test a new type of polymer gapless surge arrester for power distribution line. Metal oxide surge arrester for most electric power system applications, power distribution line and electric train are now being used extensively to protect overvoltage due to lightning. Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. When breakdown of gapless elements in a surge arrester occurs due to flashover, fault short current flows through the arrester and internal pressure of the arrester rises. The pressure rise can usually be limited by fitting a pressure relief diaphragm and transferring the arc from the inside to the outside of the housing. However, there is possibility of porcelain fragmentation caused by the thermal shock, pressure rise, etc. Non-fragmenting of the housing is the most desired way to prevent damage to other equipment. The pressure change which is occurred by flashover become discharge energy. This discharge energy raises to damage arrester housing and arrester housing is dispersed as small fragment. Therefore, the pressure relief design is requested to obstruct housing dispersion.

• International Commerce and Information Review
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• v.7 no.2
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• pp.163-181
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• 2005

The purpose of this paper is to review the major issues of trade facilitation that have been discussing in relevant international organization such as WTO, WCO, UN/ECE, and UNCTAD In recent years the term, trade facilitation, has become extremely popular and, therefore, applied to an ever-growing number of activities. Trade Facilitation encompasses the simplification, standardization, harmonization and elimination of the procedures, data requirements and administration involved in an international trade transaction. The facilitation of trade procedures is seen by all major international business as vital for economic development. Several factors are fuelling the need for trade facilitation of which two are the globalization of international trade and the rapid IT-development. Another important factor includes increased economic integration by an explosion of regional and bilateral free-trade agreement that often feature complex customs requirements. Technological progress has also introduced faster and cheaper forms of transportation and transportation management techniques, such as the increased use of e-business and JIT. The Internet is also fragmenting containers of goods that could have been custom cleared on a single entry into dozens of individual shipments that each require separate customs documents and clearance procedures. This creates a challenge for express couriers who anticipate exponential growth in small shipments by individual consumers, as compared to shipment by wholesalers or retailers. These consumers expect goods to be cleared immediately. It is no wonder that express couriers are actively promoting, and participating in the trade facilitation agenda.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.11
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• pp.1415-1425
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• 2004

The purpose of this study was to analyze a theoretical frame of expressional area, the characteristics and the effects which is applied to fashion illustration by metonymic theory. The theoretical frame of expressional area was analyzed by category analysis and 150 fashion illustrations from 1900 to 1999 were analyzed by contents analysis. The results of this study were as follows: The expressions of metonymy were categorized by close-up, realistic expression, omission, borrowing of past style, simplification and deconstruction. First, close-up was presented as emphasis of small part of fashion by cutting the scenes, snapshot, emphasis, etc. Second, realistic expression was presented as description of related circumstance with fashion message through perspective and realistic description of circumstance related to figures. Third, omission was presented as seeking of essential core by removing color, pattern, texture or by omitting body and as emphasis of communication about dominant fashion message. Fourth, borrowing of past style was presented as reminding us of background of the past. Fifth, simplification was presented as using of form or color to alleviate tension of object and to restore the essential reality. Sixth, deconstruction was presented as fragmenting of image, flattening of body and clothing, weakness of form, and strength of color. In conclusion, metonymy made by experience system of thinking based on the reality, have extended expressional territory in pre-existing fashion illustration. And these ways not only will provide fashion image as illustrator's subjective intention and theoretical system of expression of message, but also will be useful way to strengthen communication for easier interpretation of fashion illustration.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.175-179
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• 2005

The main objective of this paper is to module design and pressure relief test a new type of polymer gapless surge arrester for power distribution line. Metal oxide surge arrester for most electric power system applications, power distribution line and electric train are now being used extensively to protect overvoltage due to lightning. Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. When breakdown of gapless elements in a surge arrester occurs due to flashover, fault short current flows through the arrester and internal pressure of the arrester rises. The pressure rise can usually be limited by fitting a pressure relief diaphragm and transferring the arc from the inside to the outside of the housing. However, there is possibility of porcelain fragmentation caused by the thermal shock, pressure rise, etc. Non-fragmenting of the housing is the most desired way to prevent damage to other equipment. The pressure change which is occurred by flashover become discharge energy. This discharge energy raises to damage arrester housing and arrester housing is dispersed as small fragment. Therefore, the pressure relief design is requested to obstruct housing dispersion.