• 경영과학
• /
• 제32권1호
• /
• pp.35-47
• /
• 2015

The purpose of this paper is to find an optimal weaving connection method of sweater threads while weaving intarsia sweater by the genetic algorithm. The objective function was devised to minimize labor cost and lessen the amount of thread usage. In order to create the parental population group in the genetic algorithm, we developed five thread connection methods. Besides, elite chromosome screening methods for the offspring group was selected both to the whole chromosome thread elite and to a color-coded elite thread chromosome. Commonly used diamond pattern in Intarsia sweater manufacturing was applied to the experiments. The experimental results showed that thread system saved the labor and material costs than woven method under the existing software. When weaving Intarsia sweater in the field, we can apply the developed genetic algorithm to improve productivity of weaving connection method.

• 한국경영과학회지
• /
• 제22권2호
• /
• pp.13-29
• /
• 1997

This paper considers a new routing problem, successive max-min connection ratio problem (SMCRP), arised in circuit telecommunication networks such as SONET and WDM optical transport network. An optimization model for SMCRP is established based on link-flow formulation. It's first optimization process is an integral version of maximum concurrent flow problem. Integer condition does not give the same connection-ratio of each node-pair at an optimal solution any more. It is also an integral multi-commodity flow problem with fairness restriction. In order to guarantee fairness to every node-pair the minimum of connection ratios to demand is maximized. NP- hardness of SMCRP is proved and a heuristic algorithm with polynomial-time bound is developed for the problem. Augmenting path and rerouting flow are used for the algorithm. The heuristic algorithm is implemented and tested for networks of different sizes. The results are compared with those given by GAMS/OSL, a popular commercial solver for integer programming problem.n among ferrite-pearlite matrix, the increase in spheroidal ratio with increasing fatigue limitation, 90% had the highest, 14.3% increasing more then 70%, distribution range of fatigue.
ife was small in same stress level. (2) $\sqrt{area}_{max}$ of graphite can be used to predict fatigue limit of Ductile Cast Iron. The Statistical distribution of extreme values of $\sqrt{area}_{max}$ may be used as a guideline for the control of inclusion size in the steelmaking.

• 한국경영과학회지
• /
• 제27권1호
• /
• pp.33-51
• /
• 2002

A fully connected Artificial Neural Network (ANN) contains many connections. Compared to the pruned ANN with fewer connections, the fully connected ANN takes longer time to produce solutions end may not provide appropriate solutions to new unseen date. Therefore, by reducing the sloe of ANN, we can overcome the overfitting problem and increase the computing speed. In this research, we reduced the size of ANN by destroying the connections. In other words, we investigated the performance change of the reduced ANN by systematically destroying the connections. Then we found the acceptable level of connection-destruction on which the resulting ANN Performs as well as the original fully connected ANN. In the previous researches on the sloe reduction of ANN, the reduced ANN had to be retrained every time some connections were eliminated. Therefore, It tool lolly time to obtain the reduced ANN. In this research, however, we provide the acceptable level of connection-destruction according to the size of the fully connected ANN. Therefore, by applying the acceptable level of connection-destruction to the fully connected ANN without any retraining, the reduced ANN can be obtained efficiently.

• Journal of Construction Engineering and Project Management
• /
• 제3권4호
• /
• pp.12-19
• /
• 2013

Green Frame is an environmentally friendly column-beam system composed of composite PC members that can increase buildings' life spans while reducing resource consumption. Typically, connections of PC and RC columns occur at the boundaries of each floor, which is at the upper section of slabs, causing the boundary of each floor to generate the maximum moment. Although it is not optimal in terms of structural safety to connect members at a location where the moment is high, this approach is highly adopted due to its constructability. We propose that a superior approach that employs the concept of connecting columns at the low bending moment zone can be applied to quickly and safely install green columns, the main structural members of Green Frame. Connection of green columns at the low bending moment zone can be classified into three techniques, depending on the method of reinforcing the joints, which have different connection characteristics and construction methods. Research is needed to compare the features of each method of reinforcing the joints so that the most appropriate column connection method can be chosen for the site conditions. This study aims to confirm the structural safety of the connection component at the low bending moment zone and to compare and analyze the construction duration, unit price, quality and safety performance of each column connection method. The study results are anticipated to activate the use of composite precast concrete and to be used as development data in the future.

• Journal of Communications and Networks
• /
• 제10권4호
• /
• pp.455-464
• /
• 2008

To provide network services consistently under various network failures, enterprise networks increasingly utilize path diversity through multi-homing. As a result, multi-homed non-transit autonomous systems become to surpass single-homed networks in number. In this paper, we address an inevitable problem that occurs when networks with multiple entry points deploy firewalls in their borders. The majority of today's firewalls use stateful inspection that exploits connection state for fine-grained control. However, stateful inspection has a topological restriction such that outgoing and incoming traffic of a connection should pass through a single firewall to execute desired packet filtering operation. Multi-homed networking environments suffer from this restriction and BGP policies provide only coarse control over communication paths. Due to these features and the characteristics of datagram routing, there exists a real possibility of asymmetric routing. This mismatch between the exit and entry firewalls for a connection causes connection establishment failures. In this paper, we formulate this phenomenon into a state-sharing problem among multiple fire walls under asymmetric routing condition. To solve this problem, we propose a stateful inspection protocol that requires very low processing and messaging overhead. Our protocol consists of the following two phases: 1) Generation of a TCP SYN cookie marked with the firewall identification number upon a SYN packet arrival, and 2) state sharing triggered by a SYN/ACK packet arrival in the absence of the trail of its initial SYN packet. We demonstrate that our protocol is scalable, robust, and simple enough to be deployed for high speed networks. It also transparently works under any client-server configurations. Last but not least, we present experimental results through a prototype implementation.

• 한국시뮬레이션학회논문지
• /
• 제8권4호
• /
• pp.125-136
• /
• 1999

In the forthcoming public ATM/B-ISDN, the efficient resource management with pre-planned transit networking which public domain NNI signaling is essential to maintain high network utilization and to assure QoS to the multimedia service users. For this purpose the transit networks must be managed according to the bearer service capability which is defined by ATM Forum and ITU-T. In this paper, we introduce an implementation of ATM transit networking with ATM VP-XC(Virtual Path cross-connect) and US(Network Management System). The functions of ATM VP-XC and NMS have been simulated with OPNET 6.1 modules. We implemented the F4 OAM functions of ATM VP connection according to the ITU-T 1.610 recommendation. Also, the ATM VP transit networking is managed by the NMS according to the connection management architecture of the TWN(Telecommunications Management Network) /TINA ( Telecommunications Information Networking Architecture).

• 정보처리학회논문지C
• /
• 제9C권2호
• /
• pp.227-234
• /
• 2002

계층 3의 라우팅과 계층 2의 레이블 스위칭 기술을 통합한 MPLS는 고속의 전달, 트래픽 엔지니어링 그리고 가상 사설망 서비스의 지원을 가능하게 한다. MPLS의 레이블 스위치 및 제어기 사이에서 동작하는 GSMP 프로토콜은 연결, 구성, 장애, 성능관리 및 동기화 기능을 제공하는 개방형 인터페이스 프로토콜이다. GSMP가 적용된 개방형 인터페이스에서 망 관리를 위한 SNMP 에이전트는 레이블 스위치 또는 제어기에 탑재될 수 있다. 본 논문에서는 레이블 스위치의 단수화 및 자원 이용의 효율성을 높이기 위하여 SNMP 에이전트가 제어기에 탑재되어 GSMP와 연동하는 모델을 채택하였으며, MPLS 망 관리와 GSMP의 연동 시나리오를 제시하였다. 본 논문에서 제안된 연동 모델의 실현성을 확인하기 위하여 제어기를 구현하였으며, 연동에 따른 구성연결의 연결 설정 지연을 측정하였다.

• 융합보안논문지
• /
• 제12권4호
• /
• pp.91-96
• /
• 2012

무선 네트워크의 많은 분야 중에서 MANET(Mobile Ad-hoc Network)은 상당히 발전이 되어있는 기술이다. MANET을 구성하는 노드들은 다중 홉 무선 연결을 이용하여 데이터 전달을 하게 된다. 이러한 환경에서 노드들의 데이터 접근 성능과 가용성을 향상시킬 수 있는 방법이 캐싱 기법이다. 기존의 많은 연구들은 이동 노드들의 다중 홉 연결을 향상시키기 위해 동적인 라우팅 프로토콜에 대해 많은 연구가 이루어져왔다. 그러나 노드들의 이동으로 인하여 유효한 캐시 정보의 관리 및 유지가 쉽지 않다. 본 논문에서는 이동 노드가 원하는 정보의 캐시 발견시 오버헤드를 줄이고 노드들의 이동으로 인한 연결 관리를 위해 클러스터 기반 캐싱 기법을 제안하였다. 그리고 각 클러스터 헤드에서 유효한 캐시 테이블을 유지할 수 있도록 하기 위해 HLP를 이용하였다. 본 논문에서 제안한 기법의 효율성은 실험을 통해 확인하였다.

• 한국통신학회논문지
• /
• 제28권10B호
• /
• pp.876-890
• /
• 2003

This paper proposes a protocol for the reliableand QoS-aware multicast transport, which is called the Enhanced Communications Transport Protocol (ECTP). The ECTP has so far been developed and standardized in ITU-T SG17 and ISO/IEC JTC 1/SC 6. Differently from the conventional reliable multicast, as shownin the IETF RMT WG, the ECTP additionally provides several distinct features such as tight control of multicast session, tree-based error control, and QoS management. For the tight control of multicast connections, the sender is at the heart of one-to-many group communications, and it is responsible for overall connection management such as connection creation/termination, pause/resumption, and the join and leave operations. for tree-based reliability control, ECTP configures a hierarchical tree during connection creation. Error control is performed within each local group defined by a control tree, which was partly designed like the IETF TRACK approach. Each parent retransmits lost data in response to retransmission requests from its children. For QoS management, ECTP supports QoS negotiation for resource reservation, and it also provides QoS monitoring and maintenance operations. ECTP has been implemented and tested on Linux machine, along with Application Programming Interfaces based on Berkeley sockets. For basic testing of the ECTP functionality, we give some preliminary experimental results for performance comparison of ECTP and TCP unicast transports. In conclusion, we describe the status of ECTP experimentations over APAN/KOREN testbed networks

• 통합자연과학논문집
• /
• 제11권4호
• /
• pp.192-196
• /
• 2018

The mobile agent paradigm can be exploited in a variety of ways, ranging from low-level system administration tasks to middle ware to user-level applications. Mobile agents can be useful in building middle-ware services such as active mail systems, distributed collaboration systems, etc. An active mail message is a program that interacts with its recipient using a multimedia interface, and adapts the interaction session based on the recipient's responses. The mobile agent paradigm is well suitable to this type of application, since it can carry a sender-defined session protocol along with the multimedia message. Mobile agent communication is possible via method invocation on virtual references. Agents can make synchronous, one-way, or future-reply type invocations. Multicasting is possible, since agents can be aggregated hierarchically into groups. A simple check-pointing facility has also been implemented. Another proposed solution is to use multi agent computer systems to access, filter, evaluate, and integrate this information. We will present the overall architectural framework, our agent design commitments, and agent architecture to enable the above characteristics. Besides, the each information needed a mobile agent system such as text, graphic, image, audio and video etc, constructed a great capacity multimedia database system. However, they have problems in establishing connections over multiple subnetworks, such as no end-to-end connections, transmission delay due to ATM address resolution, no QoS protocols. We propose a new connection management scheme in the thesis to improve the connection management involved of mobile agent systems.