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FEA를 이용한 NiAl 단결정 소성 변형의 결정 방향 의존에 관한 연구 (A Study on the Orientation Dependence of Plastic Deformation in NiAl Single Crystals by FEA)

  • 양철호
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.268-273
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    • 2004
  • Deformation of single crystals was studied using finite element analysis to investigate the orientation dependence of plastic deformation observed in NiAl single crystals. Investigation of mechanical properties of single crystals is closely related with the understanding of deformation processes in single crystals. Orientation dependence of material behavior in NiAl single crystals was studied by rotating loading directions from 'hard' orientation. The maximum nominal compressed stress in NiAl single crystals was ranged in a quite wide scope depending on the misalignment from 'hard' orientation. As the compressed axis set closer to 'hard' orientation, the maximum nominal compressed stress rapidly increased and made <100> slips difficult to activate. Therefore, non-<100> slips will be activated instead of <100> slips for 'hard' orientation.

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한부모의 성역할인식과 가족복지서비스 이용이 자아존중감에 미치는 영향 (The Effects of Gender Role Attitudes and Family Service Utilization on Self-Esteem among Single Parents)

  • 이성은
    • 한국생활과학회지
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    • 제23권1호
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    • pp.1-14
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    • 2014
  • The purpose of this study is to examine the effects of gender role attitudes and family service utilization on self-esteem among single parents. This study used data from the seventh wave of Korean Welfare Panel Study and analyzed 90 single parents. Hierarchical multiple regression analyses showed that health status, economic situation, gender role attitudes, and non-monetary family welfare service had significant effects on single parents' self-esteem. Single parents who had higher traditional gender role attitudes show lower levels of self-esteem. Also use of a non-monetary family service increased the levels of self-esteem. However, use of a monetary family service was not significantly associated with the levels of self-esteem. The findings indicate that services and programs to promote single parents' gender role flexibility should be developed. Also, it is necessary to establish a service system to reduce multiple role stress among single parents.

동북아국가의 무역업무 재설계와 전자무역추진현황 -전자통관을 중심으로- (Trade Process Reengineering and e-Trade Introductionin Northeast Asia Nations-Focused on e-Customs-)

  • 최석범;박근식;김태환;김인경;박선영
    • 무역상무연구
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    • 제33권
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    • pp.277-308
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    • 2007
  • Northeast Asia Nations introduced each single window system for simplifying the customs clearance procedures in order to prevent the rekeying the customs and trade-related data. A single window is a means for enabling users to complete all the necessary import/export procedures in a single input and by single transmission by linking the related system. WCO recommends CDM, UCR, ACI that completed by WCO's own projects for assist to establish the single window for customs clearance. Northeast Asia Nations such as Korea, China, Taiwan, Japan undertook trade process reengineering for introducing single window for customs clearance. Korea and Japan introduced a e-customs systems as a good single window system. The purpose of this paper is to contribute to construction of the efficient single window system for customs clearance by studying e-customs cases in Northeast Asia Nations.

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A Study of Deformation and Orientation Dependent Behavior in Single Crystals

  • Yang Chulho
    • Journal of Mechanical Science and Technology
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    • 제19권3호
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    • pp.802-810
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    • 2005
  • Deformations of single crystals were studied using finite element analysis to investigate the localized modes and the orientation dependence of plastic deformation observed in single crystals. Investigation of mechanical properties of single crystals is closely related with the understanding of deformation processes in single crystals. Localized bands such as shear and kink were studied and the material and geometric characteristics that influence the formation of such localized bands were investigated. Orientation dependence of material behavior in NiAl single crystals was studied by rotating slip directions from 'hard' orientation. The maximum nominal compressed stress in NiAl single crystals was widely ranged depending on the misalignment from 'hard' orientation. As the compression axis was set closer to 'hard' orientation, the maximum nominal compressed stress was rapidly increased and made <100> slips difficult to activate. Therefore, non-<100> slips will be activated instead of <100> slips for 'hard' orientation.

단일루프 단일벡터 방법을 이용한 신뢰성기반 위상최적설계 (Reliability-Based Topology Optimization Using Single-Loop Single-Vector Approach)

  • 방승현;민승재
    • 대한기계학회논문집A
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    • 제30권8호
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    • pp.889-896
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    • 2006
  • The concept of reliability has been applied to the topology optimization based on a reliability index approach or a performance measure approach. Since these approaches, called double-loop single vector approach, require the nested optimization problem to obtain the most probable point in the probabilistic design domain, the time for the entire process makes the practical use infeasible. In this work, new reliability-based topology optimization method is proposed by utilizing single-loop single-vector approach, which approximates searching the most probable point analytically, to reduce the time cost. The results of design examples show that the proposed method provides efficiency curtailing the time for the optimization process and accuracy satisfying the specified reliability.

단입계 ZnO 단결정 접합체의 바리스터 거동 (Varistor Behavior of ZnO Single Crystal Monolayer Junction)

  • 김영정;김영철;안승준;민준원
    • 한국세라믹학회지
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    • 제42권5호
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    • pp.366-370
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    • 2005
  • Single gram-boundary varistors were fabricated using hydrothermal and vapor phase grown ZnO single crystals and their voltage-current relation was studied. The single crystal bonded single junction varistor showed various voltage-current relationship and different breakdown voltage of 0.24-3V. The different types of non-linear current voltage behaviors was attributed to the variation of electrical conductivity in ZnO single crystals.

Modified RCC MPPT Method for Single-stage Single-phase Grid-connected PV Inverters

  • Boonmee, Chaiyant;Kumsuwan, Yuttana
    • Journal of Power Electronics
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    • 제17권5호
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    • pp.1338-1348
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    • 2017
  • In this study, a modified ripple correlation control (RCC) maximum-power point-tracking (MPPT) algorithm is proposed for a single-stage single-phase voltage source inverter (VSI) on a grid-connected photovoltaic system (GCPVS). Unlike classic RCC methods, the proposed algorithm does not require high-pass and low-pass filters or the increment of the AC component filter function in the voltage control loop. A simple arithmetic mean function is used to calculate the average value of the photovoltaic (PV) voltage, PV power, and PV voltage ripples for the MPPT of the RCC method. Furthermore, a high-accuracy and high-precision MPPT is achieved. The performance of the proposed algorithm for the single-stage single-phase VSI GCPVS is investigated through simulation and experimental results.

Single-molecule Detection of Fluorescence Resonance Energy Transfer Using Confocal Microscopy

  • Kim, Sung-Hyun;Choi, Don-Seong;Kim, Do-Seok
    • Journal of the Optical Society of Korea
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    • 제12권2호
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    • pp.107-111
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    • 2008
  • We demonstrated single-molecule fluorescence resonance energy transfer (FRET) from single donor-acceptor dye pair attached to a DNA with a setup based on a confocal microscope. Singlestrand DNAs were immobilized on a glass surface with suitable inter-dye distance. Energy transfer efficiency between the donor and the acceptor dyes attached to the DNA was measured with different lengths of DNA. Photobleaching of single dye molecule was observed and used as a sign of single-molecule detection. We could achieve high enough signal-to-noise ratio to detect the fluorescence from a single-molecule, which allows real-time observation of the distance change between single dye pairs in nanometer scale.

단일 CNT 팁에서 탄소나노튜브의 에칭부피에 관한 연구 (A Study on the Etched Volume of Carbon Nanotube in the Single CNT Tip)

  • 이준석;최재성;강경수;곽윤근;김수현
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1126-1129
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    • 2004
  • Because of the various length condition of carbon nanotube, it is very confined the application area of the single CNT tip. In this paper, it was proposed the cutting technique of single CNT tip and the relationship between the etched volume and the amount of the applied charge. It is possible to control the length of single CNT tip arbitrary using this technique. The etched volume and length in the single CNT tip can be predicted with the amount of the applied charge. It is very easy to make a single CNT tip with proper length using this technique and to make nanotweezer that was composed two single CNT tips.

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한부모가족의 생활지원 주거대안 -코하우징을 중심으로- (A Life-supportive Housing Alternative for Single-parent Family -Focused on Cohousing-)

  • 최정신
    • 가정과삶의질연구
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    • 제22권1호
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    • pp.129-138
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    • 2004
  • The purpose of this study is to explore a life-supportive housing alternative for single-parent family, focused on cohousing. Single-parent family is considerably increasing according to diverse social changes. In foreign countries, for instance, Scandinavian countries where dual-income households and single-parent families occupy comparatively higher proportion of the whole households, cohousing has been implemented as one of the life-supportive housing alternatives. Cohousing community has been developed aiming to reduce burden of housework, child-care and loneliness through mutual support amongst inhabitants. Opinions of single-parent families are described in this study in order to explore any possibility of development of cohousing for single-parent families for their well-being in Korea. The study was fulfilled by intensive interviews with 4 heads of single-parent families as well as inhabitants of collective housing and cohousing in Korea and foreign countries.