• 전기학회논문지
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• 제63권5호
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• pp.683-689
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• 2014

The paper introduces dynamic generation technique of foot trajectories for humanoid robots using CPG(Central Pattern Generator) and proposes adaptive walking method for slope terrains combining a feedback network. The proposed CPG based technique generates the trajectory of foot in the Cartesian coordinates system and it can change the step length adaptively according to the feedback information. To cope with variable slope terrains, the sensory feedback network in the CPG are designed using the geometry relationship between foot position and body center position such that humanoid robot can maintain its stability. To demonstrate the effectiveness of the proposed approach, the experiments on humanoid robot Nao are executed in the Webot simulation. The performance and motion features of the CPG based approach are compared and analyzed focusing on the adaptability in slope terrains.

• 산업공학
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• 제11권2호
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• pp.107-117
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• 1998

This paper presents a useful method of registration in manufacturing of shadow color mask for cathode ray tubes of the FTM (Flat Tension Mask) type, wherein the shadow mask and front panel are interchangeable when mask-panels are assembled, which is called ICM system. Theoretical analysis and alignment process are presented. The pattern of mask aperture is registered with a screen pattern of corresponding geometry of the panel in flat tension mask tube. Registration accuracy of panel and mask affects the purity of color cathode ray tube concerned with mislanding. It tries to minimize the misregistration caused by variances, which are mechanical error, mask stretching position error, restrictive number of fiducial point, etc.

• 한국지구과학회지
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• 제35권7호
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• pp.501-517
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• 2014

주상절리에 관한 최근 연구를 살펴본 결과, 우리나라에 분포하는 주상절리를 이해하고, 활용하기 위한 연구 방향은 다음과 같다; 칼러네이드와 엔테블러춰의 기하학적 형태, 형성 메커니즘과 패턴의 변화, 수평단면과 내부 구조, 주상절리 상하부의 판상절리, 전분 혼합액의 건조실험, 절리 형성에 대한 수치 모델 및 컴퓨터 그래픽 활용, 화산암의 산출 상태에 따른 주상절리 형태와 크기, 모암의 암석학적 및 광물학적 연구. 이와 더불어 지표에 노출된 후의 변질, 풍화작용의 결과로 만들어진 너덜겅, 토르, 타포니 등과 같은 2차적인 경관에 대한 기재도 필요하다. 이 연구는 우리나라 주상절리와 신생대 용암류를 해석하는 중요한 역할을 할 것이다. 또한 연구 성과는 지질관광의 활성화와 지질학습장 측면에서 활용도가 높을 것이다.

• 한국재료학회지
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• 제23권8호
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• pp.453-461
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• 2013

Controlling the stick and slip motions of the contact lines in a confined geometry comprised of a spherical lens with a flat substrate is useful for manufacturing polymer ring patterns. We used a sphere on a flat geometry, by which we could control the interfaces of the solution, vapor and substrate. By this method, hundreds of concentric ring-pattern formations of a linear conjugated polymer, poly [2-methoxy-5-(2-thylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), were generated with excellent regularity over large areas after complete solvent evaporation. Subsequently, the MEH-PPV ring patterns played a role as a directed template to organize highly regular concentric rings of single-walled carbon nanotubes(SWCNTs); when a droplet of the SWCNT suspension in water was casted onto the prepared substrate, hydrophobic polymer patterns confined the water dispersed SWCNTs in between the hydrophilicized $SiO_2/Si$ substrate. As the solvent evaporated, SWCNT-rings were formed in between MEH-PPV rings with controlled density. Finally, we used a lift-off process to produce SWCNT patterns by the removal of a sacrificial polymer template with organic solvent. We also fabricated a field effect transistor using self-assembled SWCNT networks on a $SiO_2/Si$ substrate.

• 패션비즈니스
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• 제20권2호
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• pp.46-58
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• 2016

Architecture and Fashion mutually affects the shape and appearance of the other as an art of space according to the hybrid trends. Therefore, the purpose of this study is to find the correlations between the characteristics of traditional architecture types in Southeast Asia and modern fashion. Firstly, characteristics of the types obtained through the theoretical consideration of Southeast Asian architectural tradition include vertical, symmetrical, geometrical, epeated and continual structure. On the basis of these characteristics analyzed from 2013's S/S to 2015's F/W collection of Alexander McQueen, Gareth Pugh, Victor & Rolf, designers with strong creative and experimental minds who juxtaposed designs of two opposing points as well as hybrids since 2000, the following formativeness exists. First, the vertical structure of high floor is represented as a straight silhouette, a color contrast, vertical cut or wrinkle. Hence, it impresses verticality, rhythm, etc. Second, symmetrical structure of the gable roof is represented as a trapezoidal shape starting from the shoulder line or neck line widened into sleeves, impressing symmetry, dynamism, etc. Third, the geometry of the assembled is represented as vertical and horizontal bands or pattern pieces like puzzle, impressing geometry, three-dimensional, etc. Fourth, repeated structure of the weaving pattern is represented as repetitive patterns of woven fabric or printing techniques. Thus, it impresses repeatability, harmony, etc. And lastly, continuous group structure is represented as a connection of collars or hem-lines, as well as a crossing of fabric that impresses continuity, liquidity, etc.

• 대한기계학회논문집A
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• 제34권3호
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• pp.263-271
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• 2010

e-Printing은 전통 인쇄 기술을 기반으로 하는 전자소자를 생산하기위한 새로운 기술이다. 이러한 인쇄 전자 소자들은 가격을 낮추기 위하여 대면적 인쇄가 요구된다. 이렇듯 원가를 절감하며 전자 소자에 요구되는 정밀도를 충족하기 위하여 롤투롤(Roll to Roll) 방식의 그라비아(Gravure) 인쇄 시스템이 하나의 대안으로 제시된다. 그라비아 인쇄에는 인쇄 전자 소자의 성능에 영향을 미치는 요소들이 매우 많다 : 건조 방식, 건조 온도, 운전 장력, 인쇄 속도, 잉크 점도, 잉크의 전도성, 망점 및 패턴의 정밀도. 이상에서 언급한 요소들은 각각 매우 밀접한 관계를 가지고 있다. 따라서 인쇄 전자소자의 성능을 향상시키기 위해서는 반듯이 인쇄 적합조건을 찾아야만 한다. 본 논문에서는, 전도성 잉크 및 그라이아 인쇄기를 사용하여 다양한 요소의 조건을 변화하여 패턴(선 및 면)을 인쇄하였으며, 각 인쇄 요소의 변화가 인쇄 전자소자의 성능에 미치는 영향에 관하여 분석 및 연구를 수행하였다.

• International Journal of Computer Science & Network Security
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• 제24권2호
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• pp.53-58
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• 2024

This paper presents a novel miniaturized 3-D cubic antenna for use in wireless sensor network (WSN) application. The geometry of this antenna is designed as a cube including a meander dipole antenna. A truly omnidirectional pattern is produced by this antenna in both E-plane and H-plane, which allows for non-intermittent communication that is orientation independent. The operating frequency lies in the ISM band (centered in 2.45 GHz). The dimensions of this ultra-compact cubic antenna are 1.25*1.12*1cm3 which features a length dimension λ/11. The coefficient which presents the overall antenna structure is Ka=0.44. The cubic shape of the antenna is allowing for smart packaging, as sensor equipment may be easily integrated into the cube hallow interior. The major constraint of WSN is the energy consumption. The power consumption of radio communication unit is relatively high. So it is necessary to design an antenna which improves the energy efficiency. The parameters considered in this work are the resonant frequency, return loss, efficiency, bandwidth, radiation pattern, gain and the electromagnetic field of the proposed antenna. The specificity of this geometry is that its size is relatively small with an excellent gain and efficiency compared to previously structures (reported in the literature). All results of the simulations were performed by CST Microwave Studio simulation software and validated with HFSS. We used Advanced Design System (ADS) to validate the equivalent scheme of our conception. Input here the part of summary.

• 소성∙가공
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• 제7권3호
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• pp.246-259
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• 1998

This paper describes a research work of developing a computer-aided design and manufacturing of irregular shaped sheet metal product for blanking or piercing and bending operations. An approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from plasticity theories experimental results and the empirical knowledge of field experts, This system has been written in AutoLISp on the AutoCAD and in customer tool kit on the SmartCAM with a personal computer and is composed of nine modules which are input and shape treatment, flat pattern-layout, pro-processor module. Based on the knowledge-based rules, the system is designed by considering several factors, such as material and thickness of product complexities of blank geometry and punch profile sheet metal to give flat pattern and automatically account for the adjustment of bending allowances to match tooling requirements by checking dimensions and generating NC data automatically according to drawings of die-layout module. Results carried out in each module will provide efficiencies to the designer and the manufacturer of blanking or piercing and bending die in this field.

• 에너지공학
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• 제14권3호
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• pp.194-202
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• 2005

본 연구는 다양한 수직 액막형 흡수기에서 열 및 물질전달 과정에 따른 흡수 특성 예측을 이론 및 실험적으로 수행하였다. 열 및 물질전달 향상은 해석적으로 조사되었으며, 흡수 성능에 대한 유동 형태, 삽입기구 및 주름에 의한 형상 변수의 영향 등을 조사하였다. 특히, 최대 흡수 성능에 대한 동적 변수(수용액 유량, 유동형태)와 흡수기 형상(ID=22.8mm, L=1150m)의 최적값을 수치 해석적으로 예측하였다 수치 해석 및 실험에서 최대 흡수 성능은 삽입기구(스프링)에 의한 파동 유동에서 나타났다.

• 소성∙가공
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• 제19권3호
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• pp.167-172
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• 2010

Roll-to-roll forming process is one of important metal processing technology because the process is simple and economical. These days, with these merits, roll-to-roll forming process is tried to be employed in manufacturing the circuit board, barrier ribs and solar cell plate. However, it is difficult to apply to the forming of micro scale or sub-micro scale pattern. In this study, the roll forming processing for the micro scale is designed and analyzed. The forming of micro pattern for small electric device such as LCD panel by incremental roll forming process is analyzed. Firstly, the optimum analysis conditions are found by several analyses. And then, formability is analyzed for various protrusion shapes at various forming temperatures. The formability is evaluated in terms of filling ratio and damage value. The filling ratio is defined from the tool geometry and critical damage is determined from the analysis of uniaxial tensile test. Finally, optimum forming conditions that guarantee the successful forming are found.