• 한국IT서비스학회지
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• 제14권2호
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• pp.177-193
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• 2015

A great number of customers, who want to watch movies usually check out online reviews before choosing what to watch a movie. The most representative online media that customers consult are portal sites and SNS (Social Network Service). Although there have been numerous studies on online eWOM (e-Word of Mouth) and the effects of online media in businesses, it remains a question that which media is best for WOM (Word of Mouth) when selecting movies. This research examines customer's intention for consulting eWOM and for watching movies according to the number and tendency of online replies. We have compared portal sites and SNS about information of movie. The study shows that a large number of positive replies can affect the intention for WOM and choosing movies. Facebook has more influence than portal sites when choosing what to watch when replies consist of large and positive comments. However, there is no difference between the two types of media when they consist of negative comments.

• 자원환경지질
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• 제3권3호
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• pp.187-191
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• 1970

There is a discrepancy in opinion regarding geological age of Okchon system among professor C.M. Son and the writer who represent the two school of thought in precambrian stratigraphy in Korea as a whole. This brief article is a reply to the recent paper by C.M. Son titled "On the geological age of the Ogcheon Group" The discrepancy in opinion on the age Okchon system is based mainly on the difference in opinion about the age of Majeonri, Hwachonri and Kounri formations, the age of which professor Son believes as post-ordovician and regards them as a part of the Great Limestone series and the base of the Ogchon Group. The writer is in a opinion that Okchon system belong to precambrian in age and Majeonri-, Hwachonri-, and Kounri formations are the same formation composing an upper member of Okchon system. The writer's opinion is based on the facts that i) stratigraphical sequence of Okchon system established by the writer was accepted by C.M. Son who used believed the reverse order in sequence and confessed his mistake in his article; and ii) regional stratigraphy and structure strongly support's to writer's opinion. The writer pointed out and discussed in this paper various facts which do not support Son's idea by any means.

• 한국조경학회지
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• 제24권1호
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• pp.1-14
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• 1996

The purpose of this study was an analysis of the elementary school child's attitude and dangerous factors of play apparatuses n elementary schools. The results were summarized as follows; 1. 53.0% of the reply child thought that play apparatuses were dangerous, and 41.0% of the total reply had experienced accidents by apparatuses, the child under 10 had experienced the accidents manytimes. 2. The types of injuries most frequently occurred are falls from play apparatuses, and part of the body most frequently injured parts of the body are arms and legs. 3. The danger of fall in play apparatuses that is over 3M amounted 19.6%, it asked safety of bottom materials. 4. Destructed play apparatuses reached up to 20.0%, and rusted or decomposed apparatuses reached to 28.4%. 5. The distance of each apparatus were very close ; it was within 0.3~1.5M, which was 24.9%, it was very dangerous factor. 6. The most frequent hazards of educational play apparatuses are ; - inappropriate size of apparatuses(height, gap, thick etc.)- inappropriate shape and finished state(bad welding and cutting, projection part etc.)- unsuitable use of bottom material in playground and safety color.- insufficient use zone.-inappropriate maintenance and inspection(endurance passage, erosin of iron-ware and wooden ware, projection of foundation concrete)

• Journal of information and communication convergence engineering
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• 제12권3호
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• pp.154-160
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• 2014

The address resolution protocol (ARP) provides dynamic mapping between two different forms of addresses: the 32-bit Internet protocol (IP) address of the network layer and the 48-bit medium access control (MAC) address of the data link layer. A host computer finds the MAC address of the default gateway or the other hosts on the same subnet by using ARP and can then send IP packets. However, ARP can be used for network attacks, which are one of the most prevalent types of network attacks today. In this study, a new ARP algorithm that can prevent IP spoofing attacks is proposed. The proposed ARP algorithm is a broadcast ARP reply and an ARP notification. The broadcast ARP reply was used for checking whether the ARP information was forged. The broadcast ARP notification was used for preventing a normal host's ARP table from being poisoned. The proposed algorithm is backward compatible with the current ARP protocol and dynamically prevents any ARP spoofing attacks. In this study, the proposed ARP algorithm was implemented on the Linux operating system; here, we present the test results with respect to the prevention of ARP spoofing attacks.

• 무역상무연구
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• 제43권
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• pp.25-52
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• 2009

An acceptance is effected by a statement or other conduct of the offeree indicating assent. Silence or inactivity does not in itself amount to acceptance. An acceptance of an offer becomes effective at the moment the indication of assent reaches the offeror. It uses in stating rules on whether an acceptance is too late to form a contract and an offeree may withdraw an acceptance after transmission. The offeree may indicate assent by performing an act such as one relating to the dispatch of the goods or payment of the price without notice to the offeror. The acceptance by action also is to be performed within the time fixed between the parties or within a resonable time. However, an oral offer must be accepted immediately by an offeree. After an acceptance by action, the offeree avoid revocation of an offer by giving the offeror prompt notice to that effect. Even if a reply an offer contains additions, limitations or other modifications is a rejection of the offer and constitutes a counter offer, the reply to an offer contains additional and different terms which do not materially alter the terms of the offer constitutes an acceptance unless the offeror objects to the discrepancy or to that effect. Additional or different terms relating to the price, payment, quality & quantity of the goods, time & place of delivery, a party's liability or the settlement of disputes are considered to materially alter the terms of the offer.

• 한국컴퓨터정보학회논문지
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• 제5권4호
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• pp.120-125
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• 2000

기존의 인터넷 망 관리에 사용되는 SNMP(Simple Network Management Protocol)는 망 관리 정보 수집을 위한 폴링과 이에 대한 응답 트래픽으로 관리자 시스템(Management System)이 관리하는 피관리 시스템(Agent System)이 많아지면 망의 과부하를 가져올 수 있다. 본 논문에서는 기존의 SNMP에서 사용하는 폴링 방법을 개선하여 피관리 시스템이 많은 경우에 망의 과부하를 줄일 수 있는 그룹 폴링 방법을 제안하였다. 제안한 방법은 피관리 시스템들을 그룹으로 나누어 정보를 수집하는 방식으로, 기존의 방식에 비해 응답 지연시간과 통신 부하가 줄어서 피관리 시스템의 수가 많은 경우나 폴링 횟수가 많은 경우, 제안된 그룹 폴링 방법을 이용하는 것이 효율적이었다.

• 한국군사과학기술학회지
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• 제15권5호
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• pp.635-642
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• 2012

The Packet radio C2OTM(Command and Control On The Move) for Command, Control and situational awareness in communication environment of current Combat Net Radio Network is required in a relay transmission techniques. This is to assure the reliability of information transfer, and extend Wireless Coverage and overcome Communication obstacles of mountainous terrain. For the reliability of information transmission in tactical environment, Ad hoc Networking is necessary considering communication environment and an appropriate application of error correction. In this study, We propose a on-demand SDR algorithm that is currently being applied the FEC, Golay, Repetition Code. This enhanced relay transfer uses Ack Reply in tactical operating environment of MIL-STD-188-220 Protocol.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 춘계종합학술대회
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• pp.475-478
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• 2004

본 논문에서는 패킷 CDMA 망에서 데이터 서비스를 위한 코드 상태 감지 및 예약 기반의 CSSMA/AI MAC 프로토콜을 제안한다 단말기들이 코드 예약을 위한 프리앰블을 전송하기 전에 기지국에서는 매 프레임마다 예약된 코드의 상태를 방송하고, 단말기는 수신한 코드의 상태를 기반으로 임의의 예약되지 않은 코드를 예약을 위한 프리앰블을 전송한다. 프리앰블을 전송한 단말기는 선택한 코드의 하향링크를 통하여 기지국으로부터 응답을 기다린다. 기지국으로부터 코드예약에 대한 응답을 수신한 단말기는 남은 프레임 동안 패킷을 전송한다. 한편 전송한 패킷이 남아있는 경우, 기지국에서는 코드의 상태를 예약상태로 방송하고, 단말기에서는 다음 프레임에서 예약한 코드를 통하여 남은 패킷을 전송한다.

• 정보처리학회논문지C
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• 제13C권4호
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• pp.447-454
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• 2006

에드 혹 네트워크에 사용되는 라우팅 프로토콜인 AODV(Ad hoc On-demand Distance Vector)는 ERS(Expanding Ring Search) 알고리즘으로 경로설정 과정에서의 라우팅 패킷 재전송을 제어한다. 그러나 기존의 ERS는 라우팅 패킷 재전송의 기준이 되는 NTT(Node Traversal Time) 계산에 이동성이 높은 네트워크 상황을 적절하게 반영하지 못한다. 본 논문은 NTT 계산에 RREP(Route Reply) 패킷을 사용하고 출발지 노드와의 인접도에 따라 각 노드의 NTT에 가중치를 달리 적용함으로써 라우팅 패킷의 재전송률을 낮추는 방법을 제안하고 ns2를 이용하여 기존의 ERS와 성능을 비교한다.

• 한국전자통신학회논문지
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• 제15권6호
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• pp.1011-1016
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• 2020

고속 VANET(: Vehicular Ad Hoc Network)에서 네트워크 토폴로지의 급속한 변화는 라우팅 프로토콜 설계에 중요한 과제이다. 라우팅 프로토콜의 성능에 영향을 미치는 다음 홉 릴레이 노드를 선택하는 작업은 어려운 과정이다. VANET과 관련된 AODV(: Ad Hoc On-Demand Distance Vector)의 단점은 종단 간 지연 및 패킷 손실이다. 본 논문은 AODV 라우팅 프로토콜을 수정하여 방향 매개 변수와 2단계 필터링을 추가하여 RREQ(: Route Request) 및 RREP(: Route Reply) 메시지 수를 줄이는 AAODV(: Advanced AODV)기법을 제안한다. 제안된 AAODV는 패킷 손실을 줄이고 방향 매개 변수의 영향을 최소화 함으로서 패킷전달율이 증가하고, 종단 간 지연이 감소됨을 알 수 있다.