• 제목/요약/키워드: repetitive consumption

검색결과 40건 처리시간 0.032초

로드/언로드 성능향상을 위한 서스팬션의 구조최적화 (Integrated Optimal Design for Suspension to Improve Load/unload Performance)

  • 김기훈;손석호;박경수;윤상준;박노철;양현석;최동훈;박영필
    • 정보저장시스템학회:학술대회논문집
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    • 정보저장시스템학회 2005년도 추계학술대회 논문집
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    • pp.204-209
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    • 2005
  • Load/Unload(L/UL) technology includes the benefits, that is, increased areal density, reduced power consumption and improved shock resistance contrary to contact-start-stop(CSS). It has been widely used in portable hard disk drive and will become the key technology far developing the small form factor hard disk drive. The main object of L/UL is no slider-disk contact or no media damage. For realizing those, we must consider many design parameters in L/UL system. In this paper, we focus on lift-off force. The 'lift-off' force, defined as the minimum air bearing force, is another very important indicator of unloading performance. A large amplitude of lift-off force increases the ramp force, the unloading time, the slider oscillation and contact-possibility. To minimize 'lift-off' force we optimizes the slider and suspension using the integrated optimization frame, which automatically integrates the analysis with the optimization and effectively implements the repetitive works between them. In particular, this study is carried out the optimal design considering the process of modes tracking through the entire optimization processes. As a result, we yield the equation which can easily find a lift-off force and structural optimization for suspension.

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해체주의 패션의 표현 특성을 응용한 한복 디자인 개발 - 3D 디지털 패션 디자인 작품 제작을 중심으로 - (Development of hanbok design using deconstruction fashion features - Focused on the creation of 3D digital fashion design works -)

  • 한민재;양은경
    • 복식문화연구
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    • 제29권1호
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    • pp.65-86
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    • 2021
  • This study aims to develop a hanbok design method in response to recent changes in consumption trends that emphasize new aesthetic and cultural values, which contrast with the existing cultural order and repetitive normative styles in fashion designing. With this in mind, our study explores the main features of deconstruction fashion design as a theoretical guide for developing a methodology for deconstruction hanbok design, on the basis of which new, experimental and creative hanbok design works can be produced. To do this, we first investigate current trends in hanbok design and changing concepts of Korean fashion design through literature review of previous studies. Secondly, we explore deconstructionism and analyze its features to lay down the foundation for a post-modern approach in hanbok design. As the result of analysis, the main features of deconstruction fashion design are summarized as the following: 1) non-finishing, 2) decomposing and recomposing, 3) recycling, 4) transparent, 5) grunge, 6) flattening, and 7) exaggeration. Based on the identified core features of deconstruction fashion design, we develop a creative method of hanbok design in the context of modern Korean fashion design. Finally, we show five design outputs via a 3D digital fashion design process using the CLO3D software program.

AI기반 교량설계 프로세스 자동화를 위한 강화학습 알고리즘과 외부 해석프로그램 간 인터페이스 구축 (Interface Establishment between Reinforcement Learning Algorithm and External Analysis Program for AI-based Automation of Bridge Design Process)

  • 김민수;최상현
    • 한국전산구조공학회논문집
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    • 제34권6호
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    • pp.403-408
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    • 2021
  • 현재 교량과 같은 토목구조물의 설계프로세스는 1차 설계 후 구조 검토를 수행하여 기준에 부적합할 경우 재설계하는 과정을 반복하여 최종적인 성과품을 만드는 것이 일반적이다. 이러한 반복 과정은 설계에 소요되는 기간을 연장시키는 원인이 되며, 보다 수준 높은 설계를 위해 투입되어야 할 고급 엔지니어링 인력을 기계적인 단순 반복 작업에 소모하고 있다. 이러한 문제는 설계 과정 자동화를 통하여 해결할 수 있으나, 설계 과정에서 사용되는 해석프로그램은 이러한 자동화에 가장 큰 장애요인이 되어 왔다. 본 연구에서는 기존 설계 과정 중 반복작업을 대체하고자 강화학습 알고리즘과 외부 해석프로그램을 함께 제어할 수 있는 인터페이스를 포함한 교량설계 프로세스에 대한 AI기반 자동화 시스템을 구축하였다. 이 연구를 통하여 구축된 시스템의 프로토타입은 2경간 RC라멘교를 대상으로 제작하였다. 개발된 인터페이스 체계는 향후 최신 AI 및 타 형식의 교량설계 간 연계를 위한 기초기술로써 활용될 수 있을 것으로 판단된다.

잠열 축열식 칠러시스템의 제어 방식에 따른 성능 분석 (A Performance Analysis on a Chiller with Latent Thermal Storage According to Various Control Methods)

  • 강병하;김동준;이충섭;장영수
    • 설비공학논문집
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    • 제29권11호
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    • pp.592-604
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    • 2017
  • A chiller, having a thermal storage system, can contribute to load-leveling and can reduce the cost of electricity by using electricity at night. In this study, the control experiments and simulations are conducted using both conventional and advanced methods for the building cooling system. Advanced approaches, such as the "region control method", divide the control region into five zones according to the size of the building load, and determines the cooling capacities of the chiller and thermal storage. On the other hand, the "dynamic programming method" obtains the optimal cooling capacities of the chiller and thermal storage by selecting the minimum-cost path by carrying out repetitive calculations. The "thermal storage priority method" shows an inferior chiller performance owing to the low-part load operation, whereas the chiller priority method leads to a high electric cost owing to the low utilization of thermal storage and electricity at night. It has been proven that the advanced control methods have advantages over the conventional methods in terms of electricity consumption, as well as cost-effectiveness. According to the simulation results during the winter season, the electric cost when using the dynamic programming method was 6.5% and 8.9% lower than that of the chiller priority and the thermal storage priority methods, respectively. It is therefore concluded that the cost of electricity utilizing the region control method is comparable to that of the dynamic programming method.

Large-area imaging evolution of micro-scale configuration of conducting filaments in resistive switching materials using a light-emitting diode

  • Lee, Keundong;Tchoe, Youngbin;Yoon, Hosang;Baek, Hyeonjun;Chung, Kunook;Lee, Sangik;Yoon, Chansoo;Park, Bae Ho;Yi, Gyu-Chul
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.285-285
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    • 2016
  • Resistive random access memory devices have been widely studied due to their high performance characteristics, such as high scalability, fast switching, and low power consumption. However, fluctuation in operational parameters remains a critical weakness that leads to device failures. Although the random formation and rupture of conducting filaments (CFs) in an oxide matrix during resistive switching processes have been proposed as the origin of such fluctuations, direct observations of the formation and rupture of CFs at the device scale during resistive switching processes have been limited by the lack of real-time large-area imaging methods. Here, a novel imaging method is proposed for monitoring CF formation and rupture across the whole area of a memory cell during resistive switching. A hybrid structure consisting of a resistive random access memory and a light-emitting diode enables real-time monitoring of CF configuration during various resistive switching processes including forming, semi-forming, stable/unstable set/reset switching, and repetitive set switching over 50 cycles.

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PCR 방법을 이용한 우유 및 유제품에서 발생하는 식중독 균의 신속 검출법 (Rapid Detection Methods for Food-Borne Pathogens in Dairy Products by Polymerase Chain Reaction)

  • 곽혜림;한선경;김이슬;홍연;김해영
    • Journal of Dairy Science and Biotechnology
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    • 제31권2호
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    • pp.171-177
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    • 2013
  • The dairy industry has consistently grown via the expansion of dairy-based food categories. Dairy product consumption is stable since the nutrient composition in dairy products is ideal for human health. However, dairy products are highly susceptible to food-borne pathogens. Controlling the safety of dairy products is thus important when considering the nutrient-rich matrix of this food category. Currently, immunoassays or molecular biology techniques have been used to evaluate the safety of dairy products in Korea. These methods are based on the detection of proteins and thus have low reproducibility and sensitivity. Recent techniques to detect food-borne pathogens have focused on genetic analyses. Rapid detection methods for food-borne pathogens in milk and dairy products using polymerase chain reaction (PCR) techniques, such as conventional PCR, real-time PCR, repetitive sequence-based (rep)-PCR, PCR-denaturing gradient gel electrophoresis (DGGE), and digital PCR, are reviewed in this article. The aim of this review was to contribute knowledge of the relationship between microflora and the quality of dairy products. This study will also assist in the immediate monitoring of food-borne pathogens in milk and dairy products when an outbreak related to this food category occurs.

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초음파 임프린팅에서 금형온도에 따른 미세패턴의 전사특성 연구 (Replication Characteristics of Micropatterns According to Mold Temperature in Ultrasonic Imprinting)

  • 민경빈;박종한;박창용;박근
    • 대한기계학회논문집A
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    • 제38권1호
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    • pp.51-57
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    • 2014
  • 초음파 임프린팅은 열가소성 고분자 기판에 미세패턴을 복제할 수 있는 공정으로 타 성형방법에 비해 에너지소모가 적고 성형시간이 단축되는 장점이 있다. 초음파 임프린팅 공정에서는 고분자 기판의 표면에 초음파 진동에너지를 인가하여 소재간의 마찰열과 미세하게 반복되는 변형에너지의 축적을 통해 고분자 표면을 국부적으로 가소화시켜 미세패턴이 전사된다. 본 연구에서는 초음파 임프린팅에서 금형 온도가 미세패턴의 전사성에 미치는 영향을 분석하였다. 이를 위해 금형온도를 변화시켜가며 임프린팅을 수행하여 미세패턴 성형 영역에서의 온도변화를 관찰하였고, 상기 온도변화를 고려하여 미세패턴의 충진과정을 전산모사를 통해 고찰하였다. 또한 금형온도 변화에 따른 패턴의 전사율 및 전사균일도를 측정하여 비교하였다. 상기 결과를 통해 금형온도를 높일수록 초음파 임프린팅시 미세패턴의 전사특성이 향상됨을 확인할 수 있었다.

라그랑지 보간법을 이용한 로봇 매니퓰레이터의 토크 최소화를 위한 궤적계획 (Trajectory Planning for Torque Minimization of Robot Manipulators Using the Lagrange Interpolation Method)

  • 라로평;황순웅;한창수
    • 한국산학기술학회논문지
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    • 제16권4호
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    • pp.2370-2378
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    • 2015
  • 본 논문에서는 로봇 매니퓰레이터의 토크 최소화를 위한 궤적계획을 위해 라그랑지 보간법을 이용한 Algorithm을 제안하였다. 이를 위해 로봇 매니퓰레이터의 위치에 대한 구속조건이 주어지고 안정성이 보장되어야 한다. 라그랑지 보간법의 Runge's 현상을 회피하기 위해 Chebyshev 보간점을 이용하여 시간 보간점을 설정하였고, 이에 대응하는 최적각도를 찾아내어 라그랑지 보간법을 이용한 매끄러운 관절의 각도, 속도, 가속도 궤적을 얻을 수 있다. 로봇 매니퓰레이터의 토크 소비 최적화를 위한 성능지표를 선정하였으며, 계산된 궤적을 통해 이 성능지표가 최소값을 가지도록 반복 계산하는 과정을 거친다. 이를 통해, 토크와 성능지표를 최소화 시키는 최적의 궤적을 얻을 수 있으며, 로봇 매니퓰레이터가 작업을 수행하기 위한 움직임의 안전성을 보장한다.

선형적 데이터 전달의 안정성과 부하량을 고려한 무선 센서 네트워크 라우팅 프로토콜 (Routing Protocol for Wireless Sensor Network Considering Data Transmission Stability and Load Quantity)

  • 황민;천승환;유진호;;이귀상
    • 한국콘텐츠학회논문지
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    • 제7권11호
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    • pp.111-119
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    • 2007
  • 센서 네트워크는 센서 디바이스를 이용한 정보수집과 전달을 위해 필요하며, 이를 위해 여러 가지 라우팅 프로토콜이 제안되었다. 기존의 프로토콜 중 수정된 PEGASIS 라우팅 기법은 데이터 전달이 방향성을 갖는 분야에 적용하면 효과적이다. 그러나 반복되는 중계와 제어를 수행하는 센서 장치들은 자체 고장률이 높은 반면, 이 프로토콜은 장애 극복과 데이터 전달의 안정성에 대한 고려가 되어 있지 않다. 본 논문에서는 데이터 이동이 선형적인 방향성을 갖는 지그비(Zigbee) 기반의 센서 네트워크 구조상에서 안정성 있는 데이터 전달이 가능한 이중 중계 라우팅(double relay routing) 프로토콜을 제안한다. 제안된 프로토콜은 데이터 이동의 방향성을 기반으로, 에너지 소모를 최소화하면서 데이터 전달의 안정성이 확보된다는 측면에서 매우 효과적이다. 그리고 제안된 라우팅 기법을 이용한 가로등 제어시스템에 적용하여 분석을 수행하였다.

Effect of Body Mass Index on Global DNA Methylation in Healthy Korean Women

  • Na, Yeon Kyung;Hong, Hae Sook;Lee, Duk Hee;Lee, Won Kee;Kim, Dong Sun
    • Molecules and Cells
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    • 제37권6호
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    • pp.467-472
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    • 2014
  • Obesity is known to be strongly associated with cardiovascular disease and cancer, the leading causes of mortality worldwide, and develops owing to interactions between genes and the environment. DNA methylation can act as a downstream effector of environmental signals, and analysis of this process therefore holds substantial promise for identifying mechanisms through which genetic and environmental factors jointly contribute to disease risk. Global DNA methylation of peripheral blood cells has recently been proposed as a potential biomarker for disease risk. Repetitive element DNA methylation has been shown to be associated with prominent obesity-related chronic diseases, but little is known about its relationship with weight status. In this study, we quantified the methylation of Alu elements in the peripheral blood DNA of 244 healthy women with a range of body mass indexes (BMIs) using pyrosequencing technology. Among the study participants, certain clinical laboratory parameters, including hemoglobin, serum glutamic oxaloacetic transaminase, serum glutamic- pyruvic transaminase, total cholesterol, and triglyceride levels were found to be strongly associated with BMI. Moreover, a U-shaped association between BMI and Alu methylation was observed, with the lowest methylation levels occurring at BMIs of between 23 and $30kg/m^2$. However, there was no significant association between Alu methylation and age, smoking status, or alcohol consumption. Overall, we identified a differential influence of BMI on global DNA methylation in healthy Korean women, indicating that BMI-related changes in Alu methylation might play a complex role in the etiology and pathogenesis of obesity. Further studies are required to elucidate the mechanisms underlying this relationship.