• 한국산업정보학회논문지
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• 제6권2호
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• pp.31-37
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• 2001

본 연구에서는 WLL 다중채널 수신단말기 RF-모듈을 제작하였다. 그리고 WLL 다중채널 RF-모듈의 실질적인 성능을 수신감도, 인접채널 선택도, 스퓨리어스 응답제한 등의 파라미터를 이용하여 평가하였다. 실제로 WLL 다중채널용 RF-모듈을 제작하여 측정한 결과, 입력전력이 -90 dBm에서 -30 dBm까지 변화할 때 -30 dBm의 일정한 출력전력이 유지되어 약 60 dB의 동작범위를 가졌다. WLL 단말기 RF 출력단의 통과대역내의 평탄도가 약 2 dB 이내를 유지하여 대역화산신호의 전력제어가 정확히 이루어지고 있음을 확인하였다. 그리고 WLL RF 수신 전단의 전송대역폭은 10 MHz으로 본 연구의 설계목표와 정확히 일치하였다.

• 대한조선학회논문집
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• 제53권2호
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• pp.127-134
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• 2016

This paper presents practical issues for test and evaluation(T&E) methods to develop defense systems. Our argument is motivated by several domestic defense cases and the cases lead us to discuss two main factors for reliable defense systems development: 1) statistical approaches and 2) technical schemes. Specifically, statistical approaches enable to provide credible interpretations about T&E results in the decision-making process. With practical T&E results of the “Red Shark” torpedo, we performed statistical hypothesis tests and suggest a minimum sample size to accept the hypothesis. Next, technical schemes have more direct effects on improving reliability of developed defense systems and we shortly introduce tools development for systems verification that is required to integrate several sub-systems, e.g., combat, sensor, weapon, and communication systems, within a defense system. We additionally summary some domain cases using modeling and simulation techniques for successful T&E. In closing, we expect that the paper shows empirical investigation and lessons learned with these two practical issues, which provides a guide those who desire to make decisions about reliable defense systems development.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2006년도 춘계학술발표회 논문집
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• pp.177-180
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• 2006

In this paper we proposed a method of automatic point segmentation acquired by 2D laser scanner to recognize moving objects. Recently, Laser scanner is noticed as a new method in the field of close range 3D modeling. But the majority of the researches are pointed on precise 3D modeling of static objects using expensive 3D laser scanner. 2D laser scanner is relatively cheap and can obtain 2D coordinate information of moving object's surface or can be utilized as 3D laser scanner by rotating the system body. In these reasons, some researches are in progress, which are adopting 2D laser scanner to robot control systems or detection of objects moving along linear trajectory. In our study, we automatically segmented point data of 2D laser scanner thus we could recognize each of the object passing through a section.

• Journal of Plant Biology
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• 제12권2호
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• pp.7-14
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• 1969

Dunaliella tertiolecta did not show any increase in respiration rate when supplied with glucose, glycerol, sucrose, L-alanine, acetate, pyruvate and succinate. This was in contrast to Chlorella pyrenoidosa, which, under identical conditions, showed significant increase when supplied with glucose or acetate but not with the other compounds. Production of 14CO2 from added 14C-glucose in D. tertiolecta was lower than the other 14C-labelled substrates: L-alinine, glycerol, succinate, but higher than 14C-sucrose addition. And it was also lower than C. pyrenoidosa experiments which was added 14C-glucose as a substrate. Light reduced amounts of labelled carbon dioxide from 14C-glucose or 14C-acetate and increased incorporation of 14C from the substrates to cell materials in either D. tertiolecta or C. pyrenoidosa. The contribution of 14C from 14C-glucose to 14CO2 in cell-free system of D. tertiolecta were much higher than in whole cell suspension. It was contrast to C. pyrenoidosa which were showed reduction of 14CO2 production in cell-free systems than whole cell suspensions. When cell-free systems of D. tertiolecta and C. pyrenoidosa were supplied with ATP, NAD, NADP or/and hexokinase, it was remarkably increased production of 14CO2 from the substrates than the control. It was concluded that the low ability of D. tertiolecta to metabolize glucose were caused by the impermeability of the cell membrane to glucose and were not due to deficiencies of enzyme systems concerning glucose metabolism. In the cell-free systems, it seemed to be more active pentose phosphate pathway than glycolytic pathway in D. tertiolecta.

• 한국통신학회논문지
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• 제41권12호
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• pp.1748-1751
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• 2016

본 논문에서는 휘어지거나 굴곡진 array인 3차원 conformal array의 beam pattern을 보정하고자 interpolation technique을 3차원으로 확장하여 3-D uniform rectangular array(3-D URA)에 적용하는 방법을 연구하였다. 시뮬레이션 결과는 2차원 interpolation 결과보다 매우 우수한 특성을 보여준다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 봄 학술발표회논문집
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• pp.289-296
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• 2000

This paper presents a method of seismic analysis for a 2-D fluid-structure-soil interaction systems. With this method, the fluid can be modeled by spurious free 4-node displacement-based fluid elements which use rotational penalty and mass projection technique in conjunction with the one point reduced integration scheme to remove the spurious zero energy modes. The structure and the near-field soil are discretized by the standard 2-D finite elements, while the unbounded far-field soil is represented by the dynamic infinite elements in the frequency domain. Since this method directly models the fluid-structure-soil interaction systems, it can be applied to the dynamic analysis of a 2-D liquid storage structure with complex geometry. Finally, results of seismic analyses are presented for a spent fuel storage tank embedded in a layered half-space and a massive concrete dam on a layered half-space.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1219_1220
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• 2009

In recent years, the companies of electric power equipment for MV, HV class trend to develop that the eco-friendly insulated(solid, eco-gas, air etc.) switchgear replace with existent SF6 gas insulated switchgear by environmental problems such as global warming and soon. This paper introduces the Solid Insulated Switchgear(SIS) which is the epoxy of eco-friendly insulation material. The characteristic of SIS to introduce in this paper is as following. 1) Eco-friendly. (SF6 gas free) 2) The structure of flexible system. (Expansion) 3) The optimum design. (The Analysis of electrical & mechanical) 4) An Interface treatment between epoxy and insert. (Molding technology) This paper described about some technology for development of SIS.

• Applied Microscopy
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• 제52권
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• pp.1.1-1.8
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• 2022

As semiconductor device architecture develops, from planar field-effect transistors (FET) to FinFET and gate-all-around (GAA), there is an increased need to measure 3D structure sidewalls precisely. Here, we present a 3-Dimensional Atomic Force Microscope (3D-AFM), a powerful 3D metrology tool to measure the sidewall roughness (SWR) of vertical and undercut structures. First, we measured three different dies repeatedly to calculate reproducibility in die level. Reproducible results were derived with a relative standard deviation under 2%. Second, we measured 13 different dies, including the center and edge of the wafer, to analyze SWR distribution in wafer level and reliable results were measured. All analysis was performed using a novel algorithm, including auto fattening, sidewall detection, and SWR calculation. In addition, SWR automatic analysis software was implemented to reduce analysis time and to provide standard analysis. The results suggest that our 3D-AFM, based on the tilted Z scanner, will enable an advanced methodology for automated 3D measurement and analysis.

• International Journal of Control, Automation, and Systems
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• 제3권4호
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• pp.631-639
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• 2005

In this paper, we propose a constructive realization procedure for 2D systems which may lead to a Fornasini-Marchesini local state-space model with much lower order than the existing realization procedure given by Bisiacco et al. Nontrivial examples are illustrated and the conditions for minimal realization are also discussed.

• 한국멀티미디어학회논문지
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• 제18권12호
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• pp.1468-1474
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• 2015

Efficient spectrum sharing is an important issue in Device-to-Device (D2D) communications underlaying cellular networks as it can mitigate the interference to cellular users and improve the performance of the systems. In this paper, we formulate the radio resource allocation in D2D communications as a mixed nonlinear integer programing. We show the formulated problem is NP-hard and thus a polynomial time algorithm to solve is not possible. Since such a problem is very hard to obtain the optimal solution within a short running time, we instead propose a fast heuristic suboptimal algorithm to mitigate the interference caused to cellular users and improve the performance of the systems. Simulation results are provided to evaluate the performance of the proposed algorithm.