• Structural Engineering and Mechanics
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• 제51권6호
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• pp.923-937
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• 2014

The rational finite element method is different from the standard finite element method, which is constructed using basic solutions of the governing differential equations as interpolation functions in the elements. Therefore, it is superior to the isoparametric approach because of its obvious physical meaning and accuracy; it has successfully been applied to the isotropic elasticity problem. In this paper, the formulation of rational finite elements for plane orthotropic elasticity problems is deduced. This method is formulated directly in the physical domain with full consideration of the requirements of the patch test. Based on the number of element nodes and the interpolation functions, different approaches are applied with complete polynomial interpolation functions. Then, two special stiffness matrixes of elements with four and five nodes are deduced as a representative application. In addition, some typical numerical examples are considered to evaluate the performance of the elements. The numerical results demonstrate that the present method has a high level of accuracy and is an effective technique for solving plane orthotropic elasticity problems.

• 안보군사학연구
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• 통권8호
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• pp.383-420
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• 2010

This article is focusing on the improvement of weapon system test & evaluation, aimed at the weapon system in the research development stage. This article suggests improvement directions in three aspects(organization and system, skilled manpower and technology, test facilities of weapon system test & evaluation) as follows. 1) Weapon system test & evaluation organization and system a. Establishment of comprehensive test & evaluation system b. Making regulation for comprehensive test infrastructure management. c. Standardization of test & evaluation process, which can be used in special subject to army, navy and air force. 2) Skilled manpower and technology of weapon system test & evaluation a. Training & education, management of test & evaluation experts. b. Establishment of skill management system of test & evaluation. 3) Test facilities of weapon system test & evaluation a. Establishment of comprehensive improvement direction of test & evaluation installation and equipment. b. Consideration of counter measures to prevent overlapping investment, and to use the test & evaluation resources efficiently. c. Establishment of organic network for the effective use of test & evaluation installation and equipment. d. Establishment of detailed cooperation plan for the commonage of test & evaluation facility and equipment.

• 한국지진공학회논문집
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• 제27권1호
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• pp.13-24
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• 2023

In this study, alternative seismic force-resisting systems for plant structure supporting equipment were designed, and the seismic performance thereof was compared using nonlinear dynamic analysis. One alternative seismic force-resisting system was designed per the requirement for ordinary moment-resisting and concentrically braced frames but with a reduced base shear. The other seismic force-resisting system was designed by accommodating seismic details of intermediate and unique moment-resisting frames and special concentrically braced frames. Different plastic hinge models were applied to ordinary and ductile systems based on the validation using existing test results. The control model obtained by code-based flexible design and/or reduction of base shear did not satisfy the seismic performance objectives, but the alternative structural system did by strengthened panel zones and a reduced effective buckling length. The seismic force to equipment calculated from the nonlinear dynamic analysis was significantly lower than the equivalent static force of KDS 41 17 00. The comparison of design alternatives showed that the seismic performance required for a plant structure could be secured economically by using performance-based design and alternative seismic-force resisting systems adopting minimally modified seismic details.

• Steel and Composite Structures
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• 제29권3호
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• pp.301-308
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• 2018

Properties of AFS vary with the changes in the face-sheet materials. Hence, the performance of AFS can be optimized by selecting face-sheet materials. In this work, three types of face-sheet materials representing elastic-perfectly plastic, elastic-plastic strain hardening and purely elastic materials were employed to study their effects on the flexural behavior and failure mechanism of AFS systematically. Result showed face-sheet materials affected the failure mechanism and energy absorption ability of AFS significantly. When the foam cores were sandwiched by aluminum alloy 6061, the AFS failed by face-sheet yielding and crack without collapse of the foam core, there was no clear plastic platform in the Load-Displacement curve. When the foam cores were sandwiched by stainless steel 304 and carbon fiber fabric, there were no face-sheet crack and the sandwich structure failed by core shear and collapse, plastic platform appeared. Energy absorption abilities of steel and carbon fiber reinforced AFS were much higher than aluminum alloy reinforced one. Carbon fiber was suggested as the best choice for AFS for its light weight and high performance. The versus strength ratio of face sheet to core was suggested to be a significant value for AFS structure design which may determine the failure mechanism of a certain AFS structure.

• 한국항해항만학회지
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• 제39권6호
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• pp.515-521
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• 2015

본 연구는 Fuzzy-AHP를 이용하여 한 중 카페리 피견인 트레일러 상호주행 시 장애요인의 가중치 분석을 연구의 목적으로 하였다. 이를 위해 본 연구에서는 문헌연구를 통해 1차적으로 요인을 선정한 후, 현 카페리업체에 종사 중인 화물 전문가집단과의 Indepth-Interview를 수행하여 요인을 최종 선정하였다. 선정된 상위 장애 요인은 불안정적 서비스 제공, 제한적 정책 지원, 추가 비용 발생이며, 이중 불안정적 서비스 제공이 가장 큰 장애요인으로 분석되었다. 선정된 측정변수 11가지 항목은 화물 장치장 공급 부족, 트레일러 보험 및 관리 문제, 특수장비 부족, 전문화된 인력부족, 투입 서비스 항로의 제한, 마케팅 홍보 전략의 부족, 수속 비용 증가 등이며, 이중 불균형 화물 집화에 따른 장비 회송 비용 증가가 가장 큰 장애 요인으로 분석되었으며, 서비스 항로의 제한, 특수장비 부족, 수속의 지연 및 추가 절차 발생이 그 뒤를 이었다.

• 산업경영시스템학회지
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• 제46권spc호
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• pp.61-67
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• 2023

Special equipment used for snow removal is only used in the winter and must be moved into storage during non-winter seasons. However, when moving heavy equipment using a forklift within a limited space, safety accidents may occur due to deformation and damage due to the worker's limited visibility and excessive loading of heavy objects. In this study, the scissors boom of the developed heavy load transporter was conducted in two cases: link structural analysis and position-based structural analysis. In detail, the link structural analysis covers four cases of stress and safety factor according to material and thickness to optimize the specifications of the material selected during development, and the structural analysis according to position covers two cases before and after the lift, when maximum stress concentration is achieved. Safety was evaluated through finite element analysis. As a result of the study, when manufacturing a scissors boom type heavy load transporter that can withstand a load of 10 tons, the link showed safety at SS400 4.5mm or higher, and reinforcement is needed in the upper and lower structures, so it is judged to be useful in applying materials according to the load.

• 한국전자거래학회지
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• 제25권2호
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• pp.127-146
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• 2020

해외 선진국은 연구장비의 중요성을 인식하고 연구장비 산업 활성화를 위해 많은 정책적 지원을 하고 있다. 그러나 우리나라는 연구장비산업 활성화를 위한 정책이나 관련 사업을 지원할 수 있는 법률이 없다. 따라서 연구장비산업 활성화를 위한 정책과 사업을 지원하기 위한 입법이 시급하다. 연구장비산업의 글로벌 시장에서 경쟁력을 확보할 수 있도록 별도의 연구장비산업 활성화 특별법을 제정할 필요가 있다고 판단된다. 본 바와 같이 연구장비 산업 육성을 위한 다양한 진흥정책이 개발될 수 있도록 관련 법률에 필요한 사항을 명시해야 한다. 연구장비 산업발전을 촉진하기 위해서는 법에 명시해야 할 필수항목이 세 가지다. 첫째는 연구개발 지원, 둘째는 인프라 개발, 셋째는 비즈니스 육성이다. 각 내용에는 다음과 같은 내용이 포함되어야 한다. 우선 '연구개발 지원'에는 연구개발사업 추진 및 지원 정책항목, 연구장비 개발동향 및 투자동향, 산학관 공동연구, 융·복합·사업화를 위한 연구개발 지원 등이 포함된다. 다음으로 '인프라 개발' 포함될 항목에는 연구장비 클러스터 구축, 관련 지원항목, 전문인력 양성, 연구장비개발기반지역 및 기관 등이 포함되어야 한다. 마지막으로 '사업 육성'에 포함되어야 할 항목은 우수기업 육성 지원사항(우선구매제도 등), 기술이전 및 마케팅 관련 사항, 지식재산 보호에 관한 사항, 해외진출 촉진에 관한 사항 등이다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.1989-1994
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• 2012

Background and Purpose: An analysis of the current nuclear medicine (NM) status and future demand in Turkey in line with the international benchmarks was conducted to establish a comprehensive baseline reference. Methods: Data from all NM centers on major equipment and manpower in Turkey were collected through a survey and cross-checked with the primary research and governmental data. Data regarding manpower currently working were obtained from the relevant academic centers and occupational societies. Results: The current numbers of NM laboratories, NM specialists, gamma cameras, PET/CT scanners, radioiodine treatment units for thyroid cancer are 217, 474, 287, 75 and 39, respectively. There was personnel and equipment need underestimated in the field compared to developed countries. Equipment insufficiency was more significant in the Ministry of Health (MoH) hospitals. These gaps should be eliminated with strategic planning of equipment and NM laboratories. Currently, the number of the PET/CT devices is at the level of the developed countries. The number of specialists in the field should reach the expected goal in 2023. By 2023, Turkey will need around 820 NM specialists, 498 gamma cameras and 99 PET/CT devices. In addition, further studies should be made regarding other related staff, particularly for health physicians, radiopharmacists and NM technicians. Conclusion: There is an insufficiency of personnel and equipment in Turkey's NM field. Comprehensive strategic planning is required to allocate limited resources and the purchase of the equipment and employment policies should be structured as part of "National Special Feature Requiring Health Service Plan".

• 한국항행학회논문지
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• 제22권2호
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• pp.64-69
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• 2018

비행체의 탑재장비의 야전정비를 위한 자동점검장비는 특수목적을 위한 소수의 비행체를 운용할 경우에는 통합 설계하는 것이 효율적이다. 통합형 자동점검장비는 공통적으로 사용되는 인터페이스를 식별하여 각 점검대상장비 별 점검에 사용할 수 있도록 분기하거나 경로를 생성해주는 방식이 사용된다. 분기 및 경로 생성 시 RTD, TC 및 아날로그 전압과 같은 고정밀 신호는 신호분기 및 연결 시 도선저항에 의한 측정 오류가 발생할 수 있다. 이러한 도선저항에 의한 측정 오류는 점검대상장비 설계 시 많은 제약을 가져오게 된다. 본 논문에서는 아날로그 전압 및 고정밀 신호의 측정오류를 최소화 할 수 있는 통합형 자동점검장비의 고정밀 신호의 보정방법을 제시한다.

• 한국안전학회지
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• 제31권3호
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• pp.116-122
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• 2016

With the changes of industrial structure, contents and types in hazardous and dangerous works have been changed considerably. However, the hazardous and dangerous works by defined "Regulation for the hazardous and dangerous work employment restriction" and "Special education for safety and health"have not been amended over twenty years. This study aimed to identify the recent trends of the works by analyzing the death accidents cases from 2004 to 2013 and to present the management methods about future hazardous and dangerous works. The results showed that amount of 1,972 cases among 11,513 death accidents were equivalent to the works presented by "Regulation for the hazardous and dangerous work employment restriction". The amount of death accidents in 'Work of using construction equipment following construction machinery management act' was biggest among the death accidents cases and that of 'Work of handling pressure vessels following high-pressure gas safety control act' didn't show up. For the works in "Special education for safety and health"amount of 1,650 death accidents cases were equivalent. The amount of death accidents in 'Work involving a crane with a capacity of 1 ton or more or work which is carried out with a crane or hoist with a capacity of less than 1 ton in a workplace having at least 5 such machines' presented by "Special education for safety and health"was biggest. Also, death accidents case didn't occurred in three works presented by "Special education for safety and health". It was analyzed that works with low death accidents cases should be needed to study thoroughly the whole disaster research involving nonfatal accidents. Through this study, it was expected that regulation can be operated practically in the industrial field. Also, it is considered to increase