• Journal of the Korean Geotechnical Society
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• v.28 no.10
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• pp.17-25
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• 2012

Shotcrete, rockbolt, and steel rib are installed to support ground after tunnel was excavated. These are important supports for NATM applied tunnels. Recently, lattice girder is increasingly used because it is easily installed. In this study, we developed a new lattice girder by increasing contacting area between spider and rod. To verify the effect of the new lattice girder, the 3-point and 4-point flexural strength tests were carried out for LG-$50{\times}20{\times}30$, LG-$70{\times}20{\times}30$, LG-$95{\times}22{\times}32$. As a result, in case of contacting area, strength of new SGS lattice girder is 17.95% higher than that of original lattice girder. In case of weakness point, strength of new SGS lattice girder is 19.37% higher than that of original lattice girder.

• Land and Housing Review
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• v.2 no.2
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• pp.183-188
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• 2011

Recently, the depth of tunnel constructed is getting deeper, which increases difficulty in construction works. Deliberate tunneling techniques are needed as the span and length of tunnels are increased. As one of the technical developments for tunnel, U-shaped and reinforced spider lattice girders are developed by optimizing the spider used in 95mm lattice girder as tunnel steel ribs. In order to evaluate the load bearing capacity of the lattice girder, the 4-point flexural tests are carried out. For the laboratory tests, straight specimens are made for the existing lattice girder and the new lattice girder. The results of the flexural tests showed that the maximum load bearing capacity of the new lattice girders was higher than the traditional one. The load-displacement behavior of the test specimens showed the elasto-plastic behavior in the existing lattice girder and the stress softening behavior in the new lattice girder. It was found that the load bearing capacities are changed depending on the location of the loading points.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.183-188
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• 2007

We simulated a hot forging process for the spider with four legs and an enclosed die forging process for the spider with three legs using an intelligent forging simulator AFDEX 3D and compared the predictions with the experiments in terms of the deformed shape. The formation of characteristic lines was emphasized in the simulation to simulate the extruded legs with higher accuracy.

• The Journal of the Korea Contents Association
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• v.7 no.11
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• pp.205-214
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• 2007

The industrial espionage issue is not just limited on company competitiveness, but the country competitiveness depends on it too. As the number of espionage cases is increasing year by year, a damage to the country's industries rises accordingly. In this paper, we will analyse a case study of an actual industrial espionage and problems, then search for countermeasures on the issue.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.5
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• pp.82-90
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• 2020

Due to the complicated shape of the spider, the production method was changed from cold to warm forging. Finite element analysis was performed to predict the forging load and shape using the enclosed hydraulic die set. As the forging load increases due to the spider die volume, die stress analyses were performed to optimize the die design in order to reduce the die stress in various conditions. Large deformation while producing the complicated forging parts induces high forging load, which is one of the main parameters of the forging surface defects. The forging process was analyzed to find out the root cause of the surface defects generated during the spider production for various parameters, thereby revealing that the radius of die in the defect zone influenced the air trap depth, being the root cause of the surface defect. It was verified that die life was increased and the surface defect was eliminated by changing the die design during the mass production test.

• The Journal of the Korea Contents Association
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• v.17 no.7
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• pp.358-370
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• 2017

This thesis discusses the emerging system of value and structure of feeling in today's Chinese society through analyzing Chinese main theme TV series. The 2000s' Chinese main theme TV series represents Chinese's anger and nervousness into the structure of narrative, and they try to form a bond of sympathy with the audience by various characters which represent the common people. Main characters are no longer revolutionists who internalize ideas of socialism and collectivism, but they put emphasis on individuals' thoughts, tastes, and values, and freely express them. Individualism, which was negatively represented and excluded in main theme TV series before 2000s, are compromised and included in today's Chinese dramas. Even though dramas represent the superiority of communism, individuals' choice of various value and faith is positively and flexibly considered. There is a new phenomenon where female figures are no longer passive and dependent, but they are portrayed with given with unique roles and status. Although main theme TV series are directed under the state and government's supervision, they exist in the relation where market, state, drama text, and audience interact.

• Smart Media Journal
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• v.11 no.2
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• pp.70-76
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• 2022

IoT application development using a cloud server causes problems such as data transmission and reception delay, network traffic, and cost for real-time processing support in network connected hardware. To solve this problem, edge cloud-based platforms can use neuromorphic hardware to enable fast data transfer. In this paper, we propose a model optimization method for supporting spiking neural networks on FPGA hardware. We focused on auto-adjusting network model parameters optimized for neuromorphic hardware. The proposed method performs optimization to show higher performance based on user requirements for accuracy. As a result of performance analysis, it satisfies all requirements of accuracy and showed higher performance in terms of expected execution time, unlike the naive method supported by the existing open source framework.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.6
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• pp.174-181
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• 2001

An upper bound elemental technique(UBET) has been carried out to predict the forming load, the deformation pattern and the extrude length of the lateral extrusion of a spider for the automotive universal joint. For the upper bound analysis, a kinematically admissible velocity field(KAVF) is proposed. From the proposed velocity field, the upper bound load, the deformation pattern and the average length of the extruded billets are determined by minimizing the total energy consumption rate which is a function of unknown velocities at each element. Experiments are carried out with antimony-lead billets at room temperature using the rectangular shape punch. The theoretical prediction of the forming load, the deformation pattern and the extruded length are good in agreement with the experimental results.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04a
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• pp.145-147
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• 2002

컴퓨터 시스템이나 네트워크의 보안을 강화하는 방안으로 보안상 취약성이 발견되는 보안 취약성을 점검 하는 것이 옳다. 그러나 취약성을 파악하기 위하여 국내외 관련 사이트를 수동적 방법으로 검사하는 것은 대단히 어려운 일이다. 따라서 스스로 관련 사이트의 홈 페이지를 검색하고 취약성 정보를 추출한 후 새로운 취약성 관련 정보가 발견되는 대로 이를 취약성 데이터베이스에 기록하는 이른바 취약성 자동 갱신 시스템[1]은 취약성 탐지 시스템의 핵심 기능이다. 본 논문에서 구현한 취약성 자동 갱신 로봇은 웹 페이지 자동 검색프로그램인 스파이더를 활용하여 구현되었으며, ICAT등과 같은 취약점 정보 제공 사이트들로부터 홈페이지를 검색하고 이에 수록된 정보를 수집 및 분석한 후, 취약성 데이터베이스를 자동으로 갱신한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1101-1104
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• 2004

A brake spider in an irregular shape, which is used as a part in the braking system of a vehicle like a big truck and a trailer, is subjected to a large torque and hence requires both strength and endurance over the brake heat. Manufacture of this product in practice is generally composed of hot forging processes and machining. At the present study, two or more processes were considered for the hot forging. With an initial circular billet, blocker and finisher processes were analyzed using the rigid-plastic finite element method and also in addition to the preforming process. Proper forging processes to manufacture an irregular product without forging defects, which are preforming, blocker and finisher, were discussed and commented upon.