• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 추계 학술발표회
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• pp.490-496
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• 2006

In order to design accurately plastic board drain (PBB) method, it is important to determine the equivalent circle of PBD. In this paper, a series of numerical analyses on soft ground improved by PBD were carried out, in order to investigate the resonable equivalent circle of PBD considering consolidation behavior of improved soft ground by PBD. The applicability of numerical analyses, in which an elasto-viscoplastic three-dimensional consolidation finite element method was applied, could be confirmed comparing with results of a series of model tests on consolidation behaviors of soft ground improved by PBD. And, through the results of the numerical analyses, consolidation behaviors of soft ground during consolidation was elucidated, together with the equivalent circle of PBD considering consolidation behaviors.

• 한국항해학회지
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• 제22권1호
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• pp.91-106
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• 1998

Traditionally, in the education for the trainees of marine officier, the emphasis is laid on the practical training on board to prepare them for the future position on board and to fit them for the shipboard life. Though the education has been carried out in various ways according to each country's social tradition, culture and educational system, in these days it is done normally by the combined way of school education and training on board to get the competence for the marine officer. Thus the shipboard training course is compulsively required to the candidates for certification as merchant marine officers by the IMO STCW convention 1978 and also it is believed that the education for the dacet officers is to be completed through the shipboard training. In spite of the various earlier studies to improve the training education system, there are few studies for the matters and problems form the standing point of cadet.

• International Journal of Industrial Entomology and Biomaterials
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• 제24권2호
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• pp.57-61
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• 2012

The Indian Oak Tasar silkworm, Antheraea proylei J. is a beneficial insect with great economic importance in India for its silk production. In this study, six populations of Antheraea proylei and A. frithi Moore (as an out group) were subjected to inter simple sequence repeat (ISSR) marker analysis in order to assess its genetic diversity. Fifteen ISSR primers produced 91 markers among different breeds of A. proylei and A. frithi of which 89 are polymorphic, generating 97.8% polymorphism. The dendrogram constructed using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) and cluster analysis made using Nei's genetic distance resulted in the formation of one major group containing four sub-groups separating the breeds. This result suggests that ISSR amplification is potentially useful for molecular characterization of oak tasar silkworm genotypes.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권7호
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• pp.417-423
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• 2004

The headway in Korean national railway normally runs from 6 to 10 minutes. It turns out that the current signal system can not decrease the running headway of the High Speed trains, which are scheduled to set out in April, 2004, between Seoul and Daejeon, since both the existing classical trains and the High Speed ones run on the section. Thus, a new signal system is to be introduced to secure safe and reduced headway. The present paper attempts to analyze the headway between this particular section Seoul-Daejeon of the classical line, where we expect the most severe bottleneck situation to occur. We employed two modes in our analysis : the Ground Signal mode and the On-board Signal mode. which are to be adopted starting from 2006.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1465-1469
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• 2003

In general satellite verification process, the AOCS (Attitude & Orbit Control Subsystem) should be verified through several kinds of verification test which can be divided into two major category like FBT (Fixed Bed Test) and polarity test. And each test performed in different levels such as ETB (Electrical Test Bed) and satellite level. The test method of FBT is to simulate satellite dynamics with sensors and actuators supported by necessary environmental models in ETB level. The VDS (Vehicle Dynamic Simulator) try to make the real situation as possible as the on-board processor will undergo after launch. The purpose of FBT test is to verify that attitude control logic function and hardware interface is designed as expected with closed loop simulation. The VDS is one of major equipments for performing FBT and consists of software and hardware parts. The VDS operates in VME environments with target board, several commercial boards and custom boards based on the VxWorks real time operating system. In order to make time synchronization between VDS and satellite on-board processor, high reliable semaphore was implemented to make synchronization with the interrupt signal from on-board processor. In this paper, the real-time operating environment used on VDS equipment is introduced, and the hardware and software configurations of VDS summarized in the systematic point of view. Also, we try to figure out the operational concept of VDS and AOCS verification test method with close-loop simulation.

• 한국항해학회지
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• 제24권3호
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• pp.103-111
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• 2000

From a ship's safe operation point of view, it is very important to estimate the navigational safety in a seaway. The seakeeping performance can be defined as the ability of a ship to go to sea, and to accomplish its missions successfully and safely even in adverse environmental conditions. There are several factors presently adopted for evaluating seakeeping performance. But a hardware of the system considering all these factors has not been developed since some of them can not be measured by sensors. In this paper, a synthetic method of evaluating navigational safety is developed by measuring the vertical and lateral acceleration. An experiment by using real measuring carried out on board the T/S 'HANNARA' The equipment was measured every 4 hours for more than 30 minutes the acceleration by accelerometer, analyzed its acceleration values and calculated navigational dangerousness. As the results of this on board experiment, the system is carried conviction to be useful as evaluating seakeeping performance.

• 한국철도학회논문집
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• 제3권2호
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• pp.92-99
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• 2000

Composites are very useful material for light train carbody due to its high specific strength and lightweight characteristics. The composites, called 3-D board, are developed with a special stitching method. In this process, the glass fiber fabrics of skin material and foam core material are stitched together with glass fiber thread. The glass thread in Z-axis turns into FRP form. The conventional delamination problem can be solved with 3-D sandwich structure. In addition, with the lower density of foam, the weight of the panel and the operation expenses can be highly reduced. To evaluate the usefulness of the 3-D board, the double-deck light train carbody is studied. The stress analyses are carried out under various loads and boundary conditions with FEM Code, ANSYS. On comparing with the aluminum carbody, 3-D board carbody can be reduced by about 2 ton for the total weight of carbody.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2002년도 춘계학술대회 논문집
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• pp.39-43
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• 2002

Various electronic bulletin board systems (BBS) exist on the Internet. A user has to use two or more BBS. Because his/her interests may not be restricted to only one subject and BBS satisfying his/her interests may not be restricted to only one also. Furthermore, in each BBS, two or more subjects are parallel discussed while the newest contribution is always carried out. Therefore, when a user tries to keep on perusing about a specific subject, it is necessary for the user to remember in which BBS the subject exists and in the past what article of the subject was read. In this paper, we are aiming to construct an electronic bulletin board integrated management system. In this system, a user is able to use two or more BBS just like one BBS. In this paper, we present a framework of the electronic bulletin board integrated management system and implementation of a prototype system.

• 펄프종이기술
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• 제41권4호
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• pp.82-90
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• 2009

It is very important to utilize effectively fibrous waste paper in terms of cost savings, environmental effects, and governmental policies. The quality of final products and runnability of papermaking process are primarily affected by constitutions of fibrous raw materials. In specific, board grade paper depends directly on compositions of waste paper bales. At present, the raw materials of board grade paper are mainly derived from lots kinds of wastepaper. Some papermaking countries, like EU, USA and Japan have advanced classification and management systems of recycled fiber, but Korea has not yet organized systematically. In this study, evaluation of wastepaper bale compositions and their fiber properties were carried out for effective utilization of fibrous raw materials for board grade paper production. 3 kinds of wastepaper bales were classified to fibrous or non-fibrous materials. In case of fibrous materials, KOCC, kraft sack paper and white duplex board matters were main component in total weight basis, and in case of non-fibrous materials, vinyl, plastic and cloth matters were main component, in turns. 3 representative kinds of waste paper were disintegrated and classified, and then prepared to handsheet for evaluation of recycled fiber property. Consequently, fines and ash content of waste paper, isolated from KOCC and white duplex board were higher than that of kraft sack paper. pH values of all kinds of waste fibers were neutral or weak alkaline.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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• pp.67-71
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• 2008

The study analyzed on fire resistance of high strength concrete followed by thickness of fireproof plaster board and change of adhesive method. In spalling characteristics after fire resistance test, all four-side covering concretes were left out of testing screens. Thus, serious spalling was happened by exposing their internal reinforcing rods. in partial testing screens, spalling was happened till the internal concrete of main reinforcing rod. Only, temperature history didn't have special differences among changes of adhesive method. However, thickness of fireproof plaster board is very important. Namely, mock member reinforcing 25mm general adhesive + Bending was 583℃ in the highest temperature of surface part and 479℃ in the highest temperature of the main reinforcing rod, which was relatively good temperature history.