• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2101-2105
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• 2003

Recently the number of Internet users has very sharply increased, and the number of intrusions has also increased very much. Consequently, security products are being developed and adapted to prevent systems and networks from being hacked and intruded. Even if security products are adapted, however, hackers can still attack a system and get a special authorization because the security products cannot prevent a system and network from every instance of hacking and intrusion. Therefore, the researchers have focused on an active hacking prevention method, and they have tried to develop a traceback system that can find the real location of an attacker. At present, however, because of the characteristics of Internet - diversity, anonymity - the real-time traceback is very difficult. To over-come this problem the Network-based Real-Time Connection Traceback System (NRCTS) was proposed. But there is a security problem that the victim system can be hacked during the traceback. So, in this paper, we propose modified NRCTS with connection redirection technique. We call this traceback system as Connection Redirected Network-based Real-Time Connection Traceback System (CR-NRCTS).

• The Journal of Advanced Prosthodontics
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• 제13권6호
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• pp.343-350
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• 2021

PURPOSE. The success of an implant-prosthetic rehabilitation is influenced by good implant health and an excellent implant-prosthetic coupling. The stability of implant-prosthetic connection is influenced by the rotational tolerance between anti-rotational features on the implant and those on the prosthetic component. The aim of this study is to investigate the rotational tolerance of a conical connection implant system and its titanium abutment counterpart, in various conditions. MATERIAL AND METHODS. 10 preparable titanium abutments, having zero-degree angulation (MegaGen, Daegu, Korea) with an internal 5-degree conical connection, and 10 implants (MegaGen, Daegu, Korea) were used. Rotational tolerance between the connection of implant and titanium abutments was measured through the use of a tridimensional optics measuring system (Quick Scope QS250Z, Mitutoyo, Kawasaki, Japan) in the as-received condition (Time 0), after securing with a titanium screw tightening at 35 Ncm (Time 1), after tightening 4 times at 35 Ncm (Time 2), after tightening one more time at 45 Ncm (Time 3), and after tightening another 4 times at 45 Ncm (Time 4). RESULTS. The group "Time 0" had the lowest values of rotational freedom (0.22 ± 0.76 degrees), followed by the group Time 1 (0.46 ± 0.83 degrees), the group Time 2 (1.01 ± 0.20 degrees), the group Time 3 (1.30 ± 0.85 degrees), and the group Time 4 (1.49 ± 0.17 degrees). CONCLUSION. The rotational tolerance of a conical connection is low in the "as received" condition but increases with repetitive tightening and with application of a torque greater than 35 Ncm.

• 한국통신학회논문지
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• 제21권9호
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• pp.2373-2384
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• 1996

Connection caching technique is widely used to reduce the overhead incurred by frequency connection establishment in distributed computing environment using connection oriented protocol. We present an efficient connection caching scheme where we divide the system into several host groups and connection between the hosts in the same group is kept prior to others. In other words it makes the connection kept longer by sharing the connection use information between hosts in the same group. Every host group consists of hosts which have heavy intercommunication. And we present performance evaluation of the effect of host grouping upon connection caching and performance comparison of various grouping in several aspects includingmeanservice request interarrival time, mean service time, group size, grouping and type of group. Simulation results show that host grouping is effective in evrey performance criterion and proper grouping of hosts enhances the performance. We also present analysis results for Markov process model of our scheme which are consistent with the simulation results.

• 한국ITS학회 논문지
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• 제13권2호
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• pp.34-41
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• 2014

본 연구의 목적은 신뢰성 높은 교통정보 서비스를 위하여 교통정보센터 간 정보 연계체계 개선방안을 도출하는 것이다. 교통정보 연계체계의 문제점으로 교통정보센터 간 연계시간 과다 소요로 인한 오차 발생, 정보 생성시각 및 생성주체에 관한 정보 부재 등으로 인한 정보의 신뢰도 부족, 정보 연계 관리체계 미비 등의 문제점을 인식하였다. 교통정보 연계체계 개선방안으로 연계시간 최소화, 정보의 신뢰성 향상 및 연계 관리체계 구축방안을 제시하였다.

• 한국공간구조학회논문집
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• 제7권3호
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• pp.141-151
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• 2007

The appearance of many Glass Fiber Reinforced Plastic (GFRP) constructions look like ordinary steel construction, because GFRP has been imitated by the same way with the traditional steel's cross section as well as connection system. In terms of detachable connection, there was not enough appropriate option of GFRP connection, such as a traditional bolt connection for steel and wood structures. Most of all, from material characteristic of GFRP related to the deficient ductility, the shearstress principle of GFRP s not proper for the material property, which causes ineffective and not economic application of material. With this research problem, the innovative and detachable onnection system, which is more considered with appropriate material characteristic for FRP, is developed. Not only short time but also long time research with various connection variations is carried out.

• The Journal of the Acoustical Society of Korea
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• 제28권1E호
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• pp.29-34
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• 2009

MPEG4 High Efficiency Advanced Audio Coding (HE-AAC) and MPEG Surround are one of the most efficient combinations for low bit rate multi-channel audio coding. Based on the fact that these two codecs have identical quadrature mirror filter (QMF) analysis and synthesis structures, we propose a dual-domain connection scheme for the codecs. Specifically two time-domain connection methods are analyzed and compared to the QMF subband-domain connection method. Experimental results show that both the time-domain connection methods cause no subjective sound quality degradation compared to the QMF subband-domain connection method, which verifies that one can select either of them depending on application scenarios.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2001년도 춘계학술발표논문집 (상)
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• pp.507-510
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• 2001

HTTP/1.1 standard reduces latencies and overhead from closing and re-establishing connections by supporting persistent connections as a default, which encourage multiple transfers of objects over one connection. HTTP/1.1, however, does not define explicitly connection-closing time but specifies a certain fixed holding time model. This model may induce wasting server's resource when server maintains conn ection with the idle-state client that requests no data for a certain time. This paper proposes the mechanism of a heuristic connection management supported by the client-side under persistent HTTP, in addition to HTTP/1.1's fixed holding time model on server-side. The client exploits the tag information within transferred HTML page so that decides connection-closing time. As a result, the mechanism allows server to use server's resource more efficiently without server's efforts.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2001년도 봄 학술발표논문집 Vol.28 No.1 (A)
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• pp.355-357
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• 2001

HTTP/1.1 standard reduces latencies and overhead from closing and re-establishing connections by supporting persistent connections as a default, which encourage multiple transfers of objects over one connection. HTTP/1.1, however, does not define explicitly connection-closing time but specifies a certain fixed holding time model. This model may induce wasting server’s resource when server maintains connection with the idle-state client that requests no data for a certain time. This paper proposes the mechanism of a heuristic connection management supported by the client-side under persistent HTTP, in addition to HTTP/1.1’s fixed holding time model on server-side. The client exploits the tag information within transferred HTML page so that decides connection-closing time. As a result, the mechanism allows server to use server’s resource more efficiently without server’s efforts.

• 한국통신학회논문지
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• 제41권12호
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• pp.1969-1977
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• 2016

자동차 통신망의 구축비용을 획기적으로 절감하기 위해 자동차 통신망과 이동통신망을 연결하는 기지국을 대중교통수단인 버스에 설치한 자동차-이동기지국 (Vehicle-to-Mobile Roadside Unit, V2MR) 통신에 대해 연구한다. 자동차-이동기지국 통신에서 자동차들은 이동기지국에 애드 혹 연결을 설정하여 연결성을 크게 향상한다. 본 논문에서는 동일한 경로를 주행하는 자동차들과 이동기지국 간의 통신연결 시간에 대한 새로운 분석모형을 제시한다. 자동차 통신망에서 연결시간은 매우 동적이고 예측하기 힘들기 때문에, 본 논문에서 제안하는 분석모형은 자동차-이동기지국 간의 통신연결 시간을 예측하기 위한 토대를 제공할 수 있다. VEINS 시뮬에이션을 통해 수집한 실험결과를 통해 제안하는 성능분석모형이 V2MR 통신연결시간 추정 오차를 약 1 퍼센트 이내로 줄일 수 있음을 보인다. 또한, V2MR 통신이 V2R 통신에 비해 통신연결 시간을 약 3.85배 증가시킬 수 있음을 보인다.

• 한국음향학회지
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• 제42권2호
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• pp.94-101
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• 2023

음성 향상에서 많이 사용되는 U-Net과 같이 인코더와 디코더로 구성된 심층 신경망 모델은 skip-connection을 통해 인코더의 특징을 디코더에 연결하는 구조로 구성되어 있다. Skip-connection은 디코더에서 향상된 스펙트럼을 재구성하는데 도움을 주며 인코더를 통해 손실된 정보를 보완해줄 수 있다. 이때 skip-connection을 통해 연결되는 인코더의 특징과 디코더의 특징의 의미는 서로 다르다. 본 논문에서는 복소 스펙트럼 기반 음성 향상의 성능 향상을 위해 디코더에 연결되는 인코더의 특징을 디코더 특징의 의미에 가깝게 변환해주도록 skip-connection에 Self-Attention(SA)을 적용하는 방안을 연구하였다. SA는 시퀀스-시퀀스 문제에서 출력 시퀀스를 생성할 때, 입력 시퀀스의 가중 산술 평균을 이용하여 결정적인 부분을 집중해서 볼 수 있도록 하는 기법으로, 음성 향상 분야에서도 이를 적용함으로써 성능 향상에 효과적임을 입증하는 연구가 진행되었다. SA를 skip-connection에 적용하기 위해 인코더 특징과 디코더 특징을 이용하는 총 3가지의 방법에 대해 연구하였다. TIMIT 데이터베이스를 이용한 음성 향상 실험 결과, 제안하는 방법이 기존 skip-connection으로만 연결된 Deep Complex U-Net(DCUNET)과 비교하여 모든 성능 평가 지표에서 향상된 결과를 보였다.