디지털 기술의 발달로 세계가 정보 및 지식이 주도하는 사회로 급변하고, 지식 재산권의 발전이 급속하게 진행되면서, 각 기업 및 국가들은 그들의 경쟁력을 키우기 위해 지식재산권에 대한 중요성을 강조하고 있다. 이와 같이 지식재산권의 중요성이 강조되는 현실에서 지식재산권의 확보는 기업의 경쟁력을 좌우하는 요소라 할 수 있다. 따라서 본 논문에서는 빅데이터 분석 도구인 R을 이용하여 빠른 시간 안에 사용자가 목적으로 하고 있는 특허검색 결과를 효율적으로 도출할 수 있는 검색어 추출에 관한 연구를 진행하였다. 이를 위해 다섯 단계의 특허 검색 프로세스를 제안하였고 프로그램으로 구현하여 검색목적에 맞는 특허의 검색에 필요한 시간을 대폭 단축시키면서 목표로 하는 특허 검색을 효율적으로 할 수 있었다.
According to ISO 26262 (the international standard on functional safety for automotive industry), the functional safety should be considered during the whole automotive systems life cycle from the design phase throughout the production phase. In order to satisfy the standard, the automotive and related industry needs to take appropriate actions while carrying out a variety of development activities. This paper presents an approach to coping with the standard. Analyzing the standard indicates that the safety issues of the automotive systems should be handled with a system's view whereas the conventional approach to solving the issues has been practiced with focus on the component's level. The aforementioned system's view implies that the functional safety shall be incorporated in the system design from both the system's life-cycle view and the hierarchical view for the structure. In light of this, the systems engineering framework can be quite appropriate in the functional safety development and thus has been taken in this paper as a problem solving approach. Of various design issues, the analysis and verification of the safety requirements for functional safety is a key study subject of the paper. Note, in particular, that the conventional FMEA (failure mode effects analysis) and FTA (fault tree analysis) methods seem to be partly relying on the insufficient experience and knowledge of the engineers. To improve this, a systematic method is studied here and the result is applied in the design of an ABS braking system as a case study.
본 논문에서는 새로운 비중첩 영역 분할 기법을 바탕으로 한 병렬해석의 정확도 분석이 수행된다. Tak 등(2013)에 의해 제안된 이 방법에서 분할된 하위도메인들은 서로 중첩되지 않으며 계면요소(interfacial element)라 불리는 가상연결유한요소를 통해 서로 간의 관계가 결정된다. 이 접근법의 주요 장점은 영역 분할시 floating 도메인에서 발생할 수 있는 특이강성행렬(singular stiffness matrix)을 계면요소의 결합을 이용하여 가역행렬(invertible matrix)로 변환할 수 있다는 것과 기존의 FETI법에 비하여 해석시간과 스토리지(storage) 사용을 줄일 수 있다는 것이다. 반면에 3개 이상의 하위도메인들이 한 점에서 연결되는 경우를 의미하는 cross point에서는 해석의 정확도가 저하되는 경향이 나타났다. 따라서 본 논문에서는 새로운 비중첩 영역 분할기법에 대해 다양한 영역분할의 경우에 따라 발생하는 하나의 cross point에 접촉하는 하위도메인의 개수에 따른 정확도 분석이 수행되고 정확도가 저하되는 원인분석 및 대책이 논의된다.
본 논문에서는 건물의 횡방향 구조반응을 평가하기 위한 변형률 기반의 모니터링 기법이 제시되고, 이에 대한 기초 연구로써, 구조해석을 통해 제안된 기법을 검증한다. 광섬유 격자 센서(fiber Bragg grating, FBG)는 일반 변형률 센서와 비교하여 내구성이 뛰어날 뿐 아니라 높은 샘플링 수와 여러 지점을 동시에 계측할 수 있는 장점이 있다. 이러한 특성 때문에 FBG 센서는 구조 모니터링을 위해 많은 센서가 요구되는 건물의 모니터링에 적합하다. 본 연구에서 FBG 센서는 수직 부재의 변형률을 계측하며, 이는 해당 부재의 곡률을 평가한다. 이러한 곡률은 횡변위와 횡가속도를 평가하는데 사용된다. 추가적으로 횡방향 가속도는 frequency domain decomposition(FDD) 기법을 이용하여 구조물의 고유진동수와 모드형상을 추정하는데 사용된다. 9층 철골모멘트 골조 예제의 적용을 통해, 제시된 기법이 건물의 다양한 횡방향 구조 반응과 동적 특성을 평가하는데 적절함을 확인하였다.
본 논문에서는 물성이 균일하지 않은 반무한 고체영역의 탄성파속도 분포를 재구성하기 위한 시간영역 Gauss-Newton 전체파형 역해석 기법을 소개한다. 반무한 영역을 유한 계산영역으로 치환하기 위하여 유한영역의 경계에 수치적 파동흡수 경계조건인 perfectly-matched-layers(PMLs)를 도입하였다. 이 역해석 문제는 PML을 경계로 하는 영역에서의 탄성파동방정식을 구속조건으로 하는 최적화 문제로 성립되며, 표면에서 측정된 변위응답과 혼합유한요소법에 의해 계산된 응답간의 차이를 최소화함으로써 미지의 탄성파속도 분포를 결정한다. 이 과정에서 Gauss-Newton-Krylov 최적화 알고리즘과 정규화기법을 사용하여 탄성파속도의 분포를 반복적으로 업데이트하였다. 1차원 수치예제들을 통해 Gauss-Newton 역해석으로 부터 재구성된 탄성파속도의 분포가 목표값에 충분히 근사함을 보였으며, Fletcher Reeves 최적화 알고리즘을 사용한 기존의 역해석 결과에 비해 수렴율이 현저히 개선되고 계산 소요시간이 단축됨을 확인할 수 있었다.
In this paper, firstly, acceleration-time histories were generated by varying strong motion duration in the frequency domain for application to a seismically isolated nuclear power structure, so as to examine the effects of strong motion duration on the behavior of the structure. Secondly, real recorded earthquakes were modified to match the target response spectrum based on the revised SRP 3.7.1(2007) and the modified time histories were applied to the analysis of a seismically isolated nuclear power structure. The obtained values of acceleration and displacement responses of the structure were, finally, compared with the values obtained in case of applying acceleration-time histories generated in the frequency domain to the structure.
The basic critical mind in this paper is that we can change the world through the education of Chinese character. In Korea, a perspective that education of Chinese character is conservative is dominant, but it is a fact that there is undeniable inner factor. Therefore the Korean education of Chinese character makes active efforts and attempts multilateral methods in order to break away from the traditional conservatism, then it consequently has new turning point. Lately, many conferences which devise theoretical and substantive measures in education of creativity and personality for education of Chinese character are typical examples. I have suggested that using public campaign is one of good ways as a teaching‐learning method carrying out education of creativity and personality in Middle & High School education of Chinese character. The public campaign is characterized as nationwide, fairness, non‐political, public benefit, rationality, humanism, non‐profit, ethicality and non‐discriminatory. The public campaign places emphasis on rectifying social problems and establishing right ethical consciousness and values. In this respect, it can be a mean that changes the world. If such positive function of public campaign is combined with education of Chinese character, the education will be great method that changes the world. Korea and China are representative nations which are located in a cultural area of Chinese character, when we analyze public campaigns, it is found out that there are considerable number of public campaigns using Chinese characters. The public campaign of China mostly utilizes the shape of Chinese characters. Also there are many campaigns based on the shape of simplified characters(簡體字) and traditional haracters(繁體字). In the case of Korea, it shows various aspects of public campaigns than China, like campaigns using the shape of Chinese characters and vocabulary change, combining culture with Chinese character. The subject of public campaign chiefly deals with the common problem facing the world – typically such as anti‐smoking(no‐smoking), nature conservation, etc ‐ than regional problem. By imagining Chinese characters, the anti‐smoking campaigns of Korea and China deliver messages more effectively. On the other hand, the anti‐smoking campaigns of Western give horrifying impressions with realistic image. Likewise, in a cultural area of Chinese character, Chinese character shows great promise as a function changing the world. In Korea, Chinese character textbooks recently published contain public campaigns using Chinese characters. These can be classified roughly into using the shape of Chinese characters and utilizing word formation ability. However, by concentrating the rhetoric of advertising copy, so examples that can forget and damage intrinsic feature of Chinese character are also seen here and there. In the case of evaluation, I considered public campaigns used in College Scholastic Ability Test which is the most influential exam in Korea. They are divided into patterns asking Chinese character notation, subject and sentence of the chinese classics that is related to contents. The reason why public campaigns used in evaluation are more simple than public campaigns used in textbooks is that there are various restrictions when they are developed into evaluation questions. If we utilize public campaigns using Chinese characters in the learning of Chinese character, we make learners to realize the contemporary value of Chinese characters. Also, we can get effects imprinted the message on learners. For such a reason, it will be got rid of conservative of education of Chinese character and will gain great power to change world through education of Chinese character.
In order to clarify the effect of C/Ti atom ratios(χ) on the deformation behavior of TiCχ at high temperature, singlecrystals having a wide range of χ, from 0.56 to 0.96, were deformed by compression test in a temperature range of 1183~2273Kand in a strain rate range of 1.9×10−4~5.9×10−3s−1. Before testing, TiCχ single crystals were grown by the FZ method ina He atmosphere of 0.3MPa. The concentrations of combined carbon were determined by chemical analysis and the latticeparameters by the X-ray powder diffraction technique. It was found that the high temperature deformation behavior observedis the χ-less dependent type, including the work softening phenomenon, the critical resolved shear stress, the transitiontemperature where the deformation mechanism changes, the stress exponent of strain rate and activation energy for deformation.The shape of stress-strain curves of TiC0.96, TiC0.85 and TiC0.56 is seen to be less dependent on χ, the work hardening rate afterthe softening is slightly higher in TiC0.96 than in TiC0.85 and TiC0.56. As χ decreases the work softening becomes less evidentand the transition temperature where the work softening disappears, shifts to a lower temperature. The τc decreasesmonotonously with decreasing χ in a range of χ from 0.86 to 0.96. The transition temperature where the deformationmechanism changes shifts to a lower temperature as χ decreases. The activation energy for deformation in the low temperatureregion also decreased monotonously as χ decreased. The deformation in this temperature region is thought to be governed bythe Peierls mechanism.
GdBa2Cu3O7-y(Gd123) powders were synthesized by the solid-state reaction method using Gd2O3 (99.9% purity), BaCO3 (99.75%) and CuO (99.9%) powders. The synthesized Gd123 powder and the Gd123 powder with Gd2O3 addition (Gd1.5Ba2Cu3O7-y(Gd1.5)) were used as raw powders for the fabrication of Gd123 bulk superconductors. The Gd123 and Gd1.5 bulk superconductors were fabricated by sintering or a top-seeded melt growth (TSMG) process. The superconducting transition temperature (Tc,onset) of the sintered Gd123 was 93 K and the transition width was as large as 20 K. The Tc,onset of the TSMG processed Gd123 was 82 K and the transition width was also as large as 12 K. The critical current density (Jc) at 77 K and 0 T of the sintered Gd123 and TSMG processed Gd123 were as low as a few hundreds A/cm2. The addition of 0.25 mole Gd2O3 and 1 wt.% CeO2 to Gd123 enhanced the Tc, Jc and magnetic flux density (H) of the TSMG processed Gd123 sample owing to the formation of the superconducting phase with high flux pinning capability. The Tc of the TSMG processed Gd1.5 was 92 K and the transition width was 1 K. The Jcs at 77 K (0 T and 2 T) were 3.2×104 A/cm2 and 2.5×104 A/cm2, respectively. The H at 77 K of the TSMG-processed Gd1.5 was 1.96 kG, which is 54% of the applied magnetic field (3.45 kG).
Other comments on matters satisfaction survey through questionnaires typically measure by frequency analysis method is performed, the short answer for how to apply. These satisfaction surveys, however, because of the environment and atmosphere of its target at the time of the survey, personal psychological state, depending on the scale of change in business or policy of customer satisfaction feedback, there is a problem. This survey results, tangible results in terms of the feasibility of the business and policy indirectly as a result, which has been used as a material fact is. New survey method is show how the business and policy objectives than can be reflected positively in the present study, and comparing these surveys in a variety of ways for the analytical method proposed by KANO, Timko results suggested. Should be an ongoing investigation, and different survey methods for the study on the same sample the actual observed by comparing the results for the superiority of the new results presented.
본 논문에서는 와이어 하네스의 피로 내구 수명을 예측하기 위해 와이어, 번들, 실차단계의 유한요소 해석 방법론이 연구되었고 이를 위한 피로 내구 시험 기기가 개발되었다. 와이어 하네스 시스템을 구성하는 5가지 종류의 와이어에 대한 응력-수명 그래프를 얻기 위해 개발된 피로 시험기를 이용하여 반복 굽힘 움직임을 인가하였다. 와이어를 구성하는 도선과 피복의 재료 모델링을 위해 혼합의 법칙이 적용된 등가모델을 이용하였다. 번들 해석과 시험을 통하여 와이어 간의 접촉조건과 번들의 테이핑조건이 정립되었다. 와이어 및 번들 단계의 결과들은 실차 단계의 해석에 적용되었다. 실차단계의 해석을 위해 번들과 그로맷으로 구성된 와이어 하네스 시스템을 수치적으로 모델링 하였으며, 차량 문의 개폐조건이 와이어 간의 접촉조건과 함께 적용되었다. 유한요소 해석을 이용한 실차 모델의 피로 내구 해석을 통해 70만회 이상의 피로 수명이 도출 되었으며, 실차 조건의 시험 결과와비교하여 타당성을 검증하였다.
Material flow control (MFC) is a kind of operational policy to control of the movement of raw materials, components, and products through the manufacturing lines. It is very important because it varies throughput, line cycle time, and work-in-process (WIP) under the same manufacturing environments. MFC can be largely categorized into three types such as Push, Pull, and Hybrid. In this paper, we set various manufacturing environments to compare five existing MFC mechanisms: Push, Pull, and Hybrid (CONWIP, Gated MaxWIP, Critical WIP Loops, etc). Three manufacturing environments, manufacturing policies (make to stock and make to order), demand (low, medium, high), and line balancing (balanced, unbalanced, and highly unbalanced) are considered. The MFCs are compared in the point of the five functional efficiencies and the proposed compounded efficiency. The simulation results shows that the Push is superior in the functional efficiency and GMWIP is superior in the compounded efficiency.
Initially, most of ubiquitous city(hereafter u-City) projects in Korea were supported by the government because they focused on providing public services. Having constructed several u-Cities, pioneering people realized that there were several issues to successful operations such as providing useful services to citizens, supporting operational costs, continuing the need for investments, and so on. Recently, public-private collaboration efforts have increased to solve these issues. This paper studies a case of such efforts by applying a Public-Private Partnership Cooperation (PPPC) model to u-City projects. The case study introduces u-City development for an Incheon Free Economic Zone (IFEZ). It is expected that the presented case will help boost the sustain-ability of u-Cities by solving surrounding issues and providing an effective operational mechanism.
An effect of thermal annealing on activating phosphorus (P) atoms in ZnO nanorods (NR) grown using a hydrothermal process was investigated. NH4H2PO4 used as a dopant source reacted with Zn2+ ions and Zn3(PO4)2 sediment was produced in the solution. The fact that most of the input P elements are concentrated in the Zn3(PO4)2 sediment was confirmed using an energy dispersive spectrometer (EDS). After the hydrothermal process, ZnO NRs were synthesized and their PL peaks were exhibited at 405 and 500 nm because P atoms diffused to the ZnO crystal from the Zn3(PO4)2 particles. The solubility of the Zn3(PO4)2 initially formed sediment varied with the concentration of NH4OH. Before annealing, both the structural and the optical properties of the P-doped ZnO NR were changed by the variation of P doping concentration, which affected the ZnO lattice parameters. At low doping concentration of phosphorus in ZnO crystal, it was determined that a phosphorus atom substituted for a Zn site and interacted with two VZn, resulting in a PZn-2VZn complex, which is responsible for p-type conduction. After annealing, a shift of the PL peak was found to have occurred due to the unstable P doping state at high concentration of P, whereas at low concentration there was little shift of PL peak due to the stable P doping state.
우리나라는 비약적인 산업기술발전을 통해 선진국 진입을 눈앞에 두고 있다. 하지만 선진국 진입에 있어 크게 세 가지의 걸림돌이 있다. 첫째로는 세계시장 진입의 장벽, 둘째로 제조물책임법(PL법) 대응방안 미흡, 셋째로는 고객신뢰 및 자원의 한계 이다. 이러한 한계점으로 인하여 신뢰성경영시스템의 필요성이 대두되고 있으며 국내의 신뢰성경영시스템의 활성화는 필수 요소로 다가오고 있다.
본 논문에서는 신뢰성경영시스템의 활성화와 이를 위한 지표개발의 필요성 및 개발 방향성을 제시해보고자 한다.
For evaluating participation in collaboration project, the peer assement method is mostly used and various scoring methods have been proposed. But, the reliability and validity of the peer assessment method are still doubted for all most method. In order to overcome these weaknesss, some guidelines and training methods have been recommended. In this article, however, statistical technique is proposed for measuring individual contributions to collaboration projects considering each assessor’s reliability. The gist of our proposed algorithm is that an assessor’s reliability depends on the evaluation policy, and this reliability is evaluated by an analysis of variance of the scores assigned by the assessor. We also show that the proposed method is very efficient by case study in university class.
In modern systems design and development, one of the key issues is considered to be related with how to reflect faithfully the stakeholder requirements including customer requirements therein, thereby successfully implementing the system functions derived from the requirements. On the other hand, the issue of safety management is also becoming greatly important these days, particularly in the operational phase of the systems under development. An approach to safety management can be based on the use of the failure mode effect and analysis (FMEA), which has been a core method adopted in automotive industry to reduce the potential failure. The fact that a successful development of cars needs to consider both the complexity and failure throughout the whole life cycle calls for the necessity of applying the systems engineering (SE) process. To meet such a need, in this paper a method of FMEA is developed based on the SE concept. To do so, a process model is derived first in order to identify the required activities that must be satisfied in automotive design while reducing the possibility of failure. Specifically, the stakeholder requirements were analyzed first to derive a set of functions, which subsequentially leads to the task of identifying necessary HW/SW components. Then the derived functions were allocated to appropriate HW/SW components. During this design process, the traceability between the functions and HW/SW components were generated. The traceability can play a key role when FMEA is performed to predict the potential failure that can be described with the routes from the components through the linked functions. As a case study, the developed process model has been applied in a project carried out in practice. The results turned out to demonstrate the usefulness of the approach.
Delamination crack detection is very important for improving the structural reliability of laminated composite structures. This requires real-time delamination detection technologies. For composite laminates that are reinforced with carbon fiber, an electrical potential method uses carbon fiber for reinforcements and sensors at the same time. The use of carbon fiber for sensors does not need to consider the strength reduction of smart structures induced by imbedding sensors into the structures. With carbon fiber reinforced (CF/) epoxy matrix composites, it had been proved that the delamination crack was detected experimentally. In the present study, therefore, similar experiments were conducted to prove the applicability of the method for delamination crack detection of CF/polyetherethereketone matrix composite laminates. Mode I and mode II delamination tests with artificial cracks were conducted, and three point bending tests without artificial cracks were conducted. This study experimentally proves the applicability of the method for detection of delamination cracks. CF/polyetherethereketone material has strong electric resistance anisotropy. For CF/polyetherethereketone matrix composites, a carbon fiber network is constructed, and the network is broken by propagation of delamination cracks. This causes a change in the electric resistance of CF/polyetherethereketone matrix composites. Using three point bending specimens, delamination cracks generated without artificial initial cracks is proved to be detectable using the electric potential method: This method successfully detected delamination cracks.
본 논문은 기존의 1차원 Stefan 문제를 해석할 수 있는 이동최소제곱 차분법을 확장하여 복잡한 계면경계 형상을 갖는 2차원 문제에 적용할 수 있는 수치기법을 개발한다. 1차원 경우와 달리 2차원 영역에서 임의로 움직이는 이동경계의 위상변화를 효과적으로 모델링할 수 있는 기법을 제안했으며, 이동경계 모사시 절점만 사용하는 이동최소제곱 차분법의 강점을 그대로 살리면서 이동경계의 불연속 특이성과 kinetics 조건을 정확하게 만족시키는 이동최소제곱 미분근사식을 제시했다. 평형방정식은 implicit(음해)법으로 차분하여 수치 안정성을 확보했으며, 이동경계는 explicit(양해)법으로 update하여 계산효율성의 극대화했다. 몇 가지 수치예제를 통해 개발된 이동최소제곱 차분법이 다양한 계면경계 형상을 갖는 2차원 Stefan 문제를 정확하고 효율적으로 풀 수 있음을 검증했다.