• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.3
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• pp.17-22
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• 1986

This paper investigates on the performance of liquid magnetic compass measuring the concomitant angle of the directional system by the kind of compass and the coefficiant of viscosity of the liquid of ones in accordance with the turning angular velocity of the compass bowl in artificial horizontal magnetic fields. The obtained results are as follows; 1. The concomitant angle is to be in proportion to the coefficiant of viscosity of the liquid of compass and the turning angular velocity of the compass bowl, but ones is to be in contrary proportion to the magnetic moment of the magnetic needle and the horizontal geomagnetic. 2. The overdevelopment of the concomitant angle keeps on regularly at any optional degree in the turning angular velocity over$\pi$ radian per minute, but varies periodically at 180 degree below 3 $\pi$ radian per minute.

• Journal of Korean Society of Steel Construction
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• v.15 no.2
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• pp.167-174
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• 2003

This paper presented the results of cyclic loading tests of 7 full-scale beams to column subassemblages with improved connection detail i.e., fillets of the stiffening plates at the column corners and ends of the stiffener-to-beam flange weld. Major findings from the test results were: (1) Fillets reduced the stress concentrations that may cause early brittle fractures and considerably improved the cyclic performance compared to the detail without fillets. (2) As the width of the stiffening plate increased, the stiffness and peak strength increased and energy dissipation capacity decreased. (3) While all specimens failed by a fracture, they could develop a total rotation of 0.04 radian required for special moment resisting frames.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.599-607
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• 2006

텔레매틱스 정보단말기는 가독성, 시인성, 주행 안전성의 사용성과 HMI(Human Machine Interface)를 고려하여 설계해야 한다. 텔레매틱스 정보단말기 GUI을 구성하는 요소로 Menu Type, Menu Structure, Font Size 등이 있다. 그러나 한글이라는 지역적 특성에 대한 연구가 미흡한 상태이다. 따라서 본 연구에서 국내 운전자를 대상으로 텔레매틱스 정보단말기 GUI Factor에 대해 국내의 환경에 맞는 설계를 도출하였다. 피험자는 총 30명(남자 24명과 여자6명)을 대상으로 가상 주행 시스템을 이용한 시뮬레이션 환경에 Task를 수행하도록 하여 실험을 하였다. 분석은 ANOVA, 다원배치법, T-test, Font 일반식 대입을 통해 이루어졌다. Menu Type은 가로세로 2*3 배열의 형태와 버튼간 간격을 주행안전성 및 시인성에서 고려하여 설계해야 한다. Menu Structure는 3Depth가 3Frame 보다 주행안전성 및 시인성이 5%유의수준에서 더 우수하다고 나타났다. 운전자 안구 거리에 따른 Font Size를 도출하는 일반식은 어두운 글자인 경우 0.0069radian * d = Font Size 가 되고, 밝은 글자인 경우 0.0075radian * d = Font Size 가 된다. 위와 같이 본 연구는 GUI 세가지 항목에 대하여 국내 운전자의 사용성과 텔레매틱스 정보단말기 간의 인터페이스를 고려하여 기존의 시스템에 대하여 에러를 줄이고, 수행능력을 향상 시켜 주었다.

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.655-661
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• 2007

A new steel connection method using wedges known as Self-Locking Connector has been developed. In this study, experimental investigation was conducted to verify the seismic performance of steel beam-to-column joints with Self-Locking Connectors. Cyclic-loading tests were performed on two beam-to-column joints with Self-Locking Connectors. The two beam-to-column joint specimens were of the cantilever-type and had the same details. Test results showed that beam-to-column joints with Self-Locking Connectors were able to developa total rotation capacity of 0.06 radian, which is greater than the 0.04 radian required for Special Moment Frames. Moreover, their energy absorption capacity was much greater than that of conventional joints.

• Steel and Composite Structures
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• v.1 no.1
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• pp.145-158
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• 2001

An experimental study was conducted to evaluate the effects of loading sequence and lateral bracing on the behavior of reduced beam section (RBS) steel moment frame connections. Four full-scale moment connections were cyclically tested-two with a standard loading history and the other two with a near-fault loading history. All specimens reached at least 0.03 radian of plastic rotation without brittle fracture of the beam flange groove welds. Two specimens tested with the nearfault loading protocol reached at least 0.05 radian of plastic rotation, and both experienced smaller buckling amplitudes at comparable drift levels. Energy dissipation capacities were insensitive to the types of loading protocol used. Adding a lateral bracing near the RBS region produced a higher plastic rotation; the strength degradation and buckling amplitude were reduced. A non-linear finite element analysis of a one-and-a-half-bay beam-column subassembly was also conducted to study the system restraint effect. The study showed that the axial restraint of the beam could significantly reduce the strength degradation and buckling amplitude at higher deformation levels.

• Journal of the Earthquake Engineering Society of Korea
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• v.18 no.2
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• pp.95-103
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• 2014

The current AISC341-10 standard specifiesa value of 0.02 radian for the minimum rotation capacity of connections for the intermediate steel moment frame system. However, despite of the advances realized in the domains of performance evaluation method and analysis method, research onthe minimum rotation capacity of the intermediate steel moment frame systemsatisfying the seismic performance has not been conducted in detail. In this study, the intermediate moment frame systemisdesigned with respect to current standards and the seismic performance in accordance with the rotational capacity of connections is evaluated using the seismic performance evaluation method presented in FEMA-P695. The minimum rotation capacity of intermediate steel moment frames required to satisfy seismic performance as well as the major design values affecting the seismic performance of moment frame areestimated. To that goal, the design parameters are selected and various target frames are designed. The analysis models of the main nonlinear elements are also developed for evaluating seismic performance. The resultsshow that the 20-story structure doesnot meet the seismic performance even if it satisfies the rotation capacity of 0.02 radian.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.450-453
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• 1997

An active control for the swing of crane systems is very important for increasing the productivity. This article introduces the control for the position and the swing of a crane using the fuzzy learning method. Because the crane is a multi-variable system, learning is done to control both position and swing of the crane. Also the fuzzy control rules are separately acquired with the loading and unloading situation of the crane for more accurate control. The result of simulations shows that the crane is just controlled for a very large swing angle of 1 radian within nearly one cycle.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.6
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• pp.40-45
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• 2000

교정은 모든 측정분야에서 어렵고 까다로운 주제인데, 특히 정전센서, 레이저간섭계, AFM, STM 등을 포함하는 나노메트롤로지(nanometrology : 나노측정) 분야에서는 그러하다. 나노측정에서는 전체 측정범위가 센서들의 한계분해능 값과 비슷한데, 이러한 측정에서 높은 소급성을 유지하기는 매우 어렵기 때문이다.(중략)

• Journal of Korean Society of Steel Construction
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• v.18 no.1
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• pp.59-69
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• 2006

This paper presents test results on reduced beam section (RBS)program addressed panel zone (PZ) strength as the key variables. PZ strength has been much debated issue for several decades. A desirable range of PZ strength has not yet been proposed despite the fact that a significant amount of RBS test data is available. Test results from this study and by others showed that panel zones could easily develop a plastic rotation of 0.01 radian without causing distress to the beam flange groove welds. At this deformation level, the amount of beam distortion (i.e., buckling) was about one half that developed in strong PZ specimens. A criterion for a balanced PZ strength that improves the plastic rotation capacity while reducing the amount of beam buckling is proposed.

• Journal of Korean Society of Steel Construction
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• v.14 no.4
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• pp.499-508
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• 2002

A simple design method for rib-reinforced seismic steel moment connections has been recently proposed based on the equivalent strut model. An experimental program was implemented to verify the proposed design method, as well as develop the schemes that will prevent cracking at the rib tip where stress concentration was evident. All specimens designed using the proposed method were able to develop a satisfactory connection plastic rotation of 0.04 radian. In addition to rib reinforcement, slight beam flange trimming pushed the plastic hinging and local buckling of the beam away from the rip tip and effectively reduced cracking potential at the rib tip. Using strain gage readings, the strut action of the rib and resulting reverse shear in the beam web were also experimentally identified.