• International Journal of Naval Architecture and Ocean Engineering
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• 제9권2호
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• pp.219-226
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• 2017

These days, the great part of design processes in the field of ship or offshore manufacturing are planned and implemented using the CAD system customized for shipbuilding companies. It means that all information for design and production could be extracted and reused at the other useful fields which need cost considerable time and efforts. The typical example is the field of welding material quantity evaluation which is demanded during the construction of ship or offshore structures. The proper evaluation of welding material to be used and the usage of them at the stage of schedule planning are mostly important to achieve the seamless process of production and costing in advance. This study is related to the calculation of welding length and needed welding material quantity at the stage of design completion utilizing the customized CAD system. The calculated welding material quantity would be classified according to welding posture, assembly stage, block, bevel and welding type so as to improve the accuracy of total cost evaluation. Moreover it is possible to predict the working time for welding operation and could be used efficiently for the cost management using the results of this research.

• Child Health Nursing Research
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• 제25권4호
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• pp.528-540
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• 2019

Purpose: This study was conducted to design services for improving the quality of care of hospitalized children with acute diseases. Methods: The service design process had four phases: discovery, definition, development, and delivery. The participants were 23 mothers of hospitalized children with an acute disease, and seven nurses and three doctors working at a pediatric hospital. Data were collected through self-report questionnaires, in-depth interviews, and observations. The data were analyzed using content analysis and descriptive statistics. Results: The participants reported needs for explanations about the treatment, skillful nursing, and environmental improvements. The concept of the services was familiarity and enjoyment, aimed at solving the problems of unfamiliarity and boredom. A six-guideline was presented for improving the quality of care of hospitalized children with acute diseases: improvement of awareness, development of educational materials, improvement of skills, environmental improvements, play activities, and evaluations of user satisfaction. Conclusion: These findings indicate that nursing services should deliver familiarity and enjoyment to hospitalized children and their families. The findings of this study emphasize that the service design methodology can be used to improve the quality of care of hospitalized children with acute diseases.

• Nuclear Engineering and Technology
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• 제56권1호
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• pp.222-232
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• 2024

New modular factory-built methodologies implemented in the construction and industrial plant industries may bring down costs for modular reactors. A factory-built environment brings about benefits such as; improved equipment, tools, quality, shift patterns, training, continuous improvement learning, environmental control, standardisation, parallel working, the use of commercial off shelf equipment and much of the commissioning can be completed before leaving the factory. All these benefits combine to reduce build schedules, increase certainty, reduce risk and make financing easier and cheaper.Currently, the construction and industrial chemical plant industries have implemented successful modular design and construction techniques. Therefore, the objectives of this paper are to understand and analyse the state of the art research in these industries through a systematic literature review. The research can then be assessed and applied to modular reactors.The literature review highlighted analysis methods that may prove to be useful. These include; modularisation decision tools, stakeholder analysis, schedule, supply chain, logistics, module design tools and construction site planning. Applicable research was highlighted for further work exploration for designers to assess, develop and efficiently design their modular reactors.

• 한국수소및신에너지학회논문집
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• 제25권6호
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• pp.648-655
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• 2014

This paper describes the continuing effort to develope a single acting free-piston Stirling engine/alternator combination for use of the household cogeneration. Free piston Stirling engines(FPSE) use variations of working gas pressure to drive mechanically unconstrained reciprocating elements. Stirling cycle free-piston engines are driven by the Stirling thermodynamic cycle which is characterized by an externally heated device containing working gas that is continuously re-used in a regenerative, reversible cycle. The ideal cycle is described by two isothermal process connected by two constant volume processes. Heat removed during the constant volume cooling process is internally transferred to the constant volume heating process by mutual use of a thermal storage medium called the regenerator. Since the ideal cycle is reversible, the ideal efficiency is that of Carnot. Free-piston Stirling engine is have no crank and rotating parts to generate lateral forces and require lubrication. The FPSE is typically comprised of two oscillating pistons contained in a common cylinder. The temperature difference across the displacer maintains the oscillations, and the FPSE operate at natural frequency of the mass-spring system. The power is generated from a linear alternator. The purpose of this paper is to describe the design process of the single acting free-piston Stirling engine/alternator. Electrical output of the single acting free-piston Stirling engine/alternator is about 0.95 kW.

• 대한기계학회논문집A
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• 제34권3호
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• pp.375-382
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• 2010

본 논문에서는 In-Mold Labeling(IML) 공정을 이용한 제품생산 과정에서 발생하는 잔류응력과 열변형을 예측할 수 있는 해석모델을 개발하였다. IML 은 선 공정된 필름을 금형에 넣은 후 수지를 사출하여 제품을 생산하는 방법으로, 일반적인 사출성형 공정방법에 비해 뛰어난 색감을 구현할 수 있을뿐 아니라, 반영구적 보존 등의 다양한 장점을 얻을 수 있다. 반면, IML 공정을 이용한 제품 생산의 경우 필름박리 등의 다양한 불량 현상이 발생하기도 하는데, 이 중 필름박리 현상의 주요한 원인 중 한가지로 지목되는 열 변형 현상을 수치해석을 통해 예측하고, 실제 실험결과와 비교하여 연구의 신뢰성을 검증하였다. 이는 IML 공정을 통해 생산되는 제품의 초기설계 단계로부터 필름박리 및 열 변형을 예측하는데 활용될 수 있을 것으로 기대된다.

• 한국건설관리학회논문집
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• 제20권2호
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• pp.95-104
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• 2019

EPC 플랜트 프로젝트는 규모와 복잡성 측면에서 시공 이전 단계의 계획 업무가 프로젝트 성패에 큰 영향을 미치기 때문에 프로젝트에 참여하는 주체간의 긴밀한 협력과 의사소통이 필수적이다. 본 연구는 이러한 필요성을 기반으로 플랜트 프로젝트에서 자산데이터를 활용하여 공정계획의 요소정보를 추출하고, 이를 패키지로 구성하여 초기 공정계획을 수행하는 방법론을 상호계획 (IAP, Interactive Planning)의 개념을 통해 제시한다. 프로젝트 초기단계에서 효과적인 IAP를 수행하기 위하여 자산 데이터로부터 공정요소정보를 추출하고 작업 패키지 단위의 공정 계획을 작성하며 작성된 공정계획을 평가하는 세 가지 단계를 제시하였으며 이를 샘플 프로젝트 사례에 적용하였다. 제시된 IAP 방법론을 통해 자산 데이터 활용성 증진과 공정 리스크 사전식별 및 대응책 개발을 도모할 수 있으며 이는 프로젝트를 성공적으로 완료하기 위한 공정 전략 수립의 기반이 될 수 있다.

• 융합보안논문지
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• 제8권1호
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• pp.101-108
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• 2008

본 연구에서는 항만 물류 프로세스의 현황과 장애요인을 분석하고, Lean이론을 적용한 프로세스의 재설계를 통해 이를 개선하기 위한 방안을 도출하는 한편, 개선된 프로세스를 통한 항만물류시스템을 구축하기 이전 과정을 철강기업 내에 특화된 부두 운영 업무 중 슬라브 관리업무에서 항만물류프로세스의 관련 주체를 선별하고 각 주체간의 관계를 파악하여 부두, 조업, 출하, 공정, 품질, 구매에 이르는 관리업무를 정의하고 각각 개체사이의 정보와 슬라브의 흐름에서 Lean 도구를 사용하여 기존 프로세스 상에 Value added와 Non-Value added를 분석하여 Cycle Time의 감소, 재고감소, 업무전환시간의 감소, 재작업감소, 서비스개선, 낭비 감소 등을 목표로 업무프로세스를 정형화시키고, 항만현장이 항만물류프로세스를 최적의 상황으로 실행 할 수 있도록 환경의 재설계를 통한 항만물류프로세스의 개선된 모델을 제시한다.

• Design & Manufacturing
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• 제6권2호
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• pp.70-73
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• 2012

Drill process is usually used to manufacture a industry about processing, Therefore, the burr problem is very significant, The burrs took place when drill process. And then, sometimes, the burrs are often caused of some problems during automatic such as no good quality products and having good surface roughness products. And also, this paper had some experiments using magnesium. Specially, the magnesium is one of the non-ferromagnetic materials. Magnesium has attracted a lot of interest for using the industry. They offer a possible alternative to steel and aluminum in automotive and aero industries to satisfy the lightweight requirement. also, magnesium has good specific strength and absorbs vibration in occurring working process. So, it has good quality of product processing. And then, it is one of the lightest materials being used to electronic product's cases and automotive because of lightweight and miniaturization. But this material has not widely used all of the industry due to its natural property. If the magnesium is contacted water, it will cause the exploration. But, nowadays many of people study magnesium to safe their experiment and to widely use this industry.

• Environmental Engineering Research
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• 제16권4호
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• pp.243-252
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• 2011

Several mathematical relationships have been developed to describe bacterial responses to UV irradiation. Pseudomonas aeruginosa was taken as a bacterial model. The results obtained showed that the kinetics of disinfection is far to be as uniform. In fact, application of the model of Chick-Watson in its original form or modification, taking into account the speed change during the disinfection process, has not significantly improved results. The application of both models of Collins-Selleck and Hom constitute a major opportunity to simulate goodly the kinetics of UV disinfection. The results obtained showed that despite the major advantage held by applying the Hom model in this process of disinfection and for all strains studied, the model of Collins-Selleck gave the best results for the description of the UV inactivation process. The design of reactors, operating in continuous disinfection system, requires taking into account the hydrodynamic behaviour of water in the reactor. Knowing that a reduction of 4-log is necessary in the case of wastewater reuse for irrigation, a model integrating the expression of disinfection kinetics and the hydrodynamics through the UV irradiation room was proposed. The results highlight the interest to develop reactors in series working as four perfectly mixed reactors.

• 한국정밀공학회지
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• 제19권7호
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• pp.97-105
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• 2002

The use of rapid prototyping (RP) has reduced time to market, cut total costs and improved product quality by giving design and manufacturing teams the opportunity to verify and fine tune designs before committing them to expensive tooling and fabrication. In order to improve their unique characteristics according to the working principles, Variable Lamination Manufacturing process (VLM-ST) and corresponding CAD/CAM software (VLM-Slicer) is developed. The objective of this study is to improve the accuracy of VLM-ST process, and it can be done by offset fur cutting error correction, cutting path overrun fur sharp edge and reference shape generation for off-line stacking. It has been shown that, through the verification experiments for given practical shapes, the proposed algorithms are effective for diverse categories of three-dimensional shapes.