기계요소설계 과목을 위한 교육용 소프트웨어 개발

박경진,도성희,Park, Gyung-Jin,Do, Sung-Hee 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.8

Machine element design is a very important course in the undergraduate program of mechanical engineering in that it presents traditional design concepts. While computer aided design(CAD) receives more attention, students tend to ignore the machine element design or traditional design concepts. However, design methodologies related to machine elements are utilized quite often in practical fields. Also, design methodologies provide good insight for the decision making process of modern design. Generally, CAD is used for simple drafting without the real design process in the undergraduate program. Design software has been developed for various machine elements. Through menu display, a user can select or furnish the design input such as design objects, dimensions, environmental forces and usages, and safety factors. Then the software carries out the design processes which are the same as those of textbooks. The result of the design is filtered to have the values in the standards. The designed machine element is drawn via commercial CAD software. The software has been developed with C language on a personal computer. The developed software is being utilized successfully in a design course, and the experiences are discussed in this paper. The software can be used in industries which require the repeated process of the machine element design.

식중독 경험 및 식품안전에 대한 인식 조사

박경진,천석조,박기환,홍종해,김정원,Park, Gyung-Jin,Chun, Seok-Jo,Park, Ki-Hwan,Hong, Chong-Hae,Kim, Jeong-Weon 한국식품위생안전성학회 2003 한국식품위생안전성학회지 Vol.18 No.3

본 조사는 한국 소비자들의 식중독 경험여부, 식중독 원인균에 대한 지식 및 식품안전과 식중독 예방을 위한 행동에 있어서의 인식 정도를 알아보기 위하여 2001년 11월 일반성인 총 1,040명을 대상으로 전국적으로 전화조사를 실시하였다. 그 결과 12.4%는 연 1회 이상 식중독을 경험하고 있으며, 0.3%는 식중독으로 인해 병원에 입원하는 것으로 나타났다. 식중독이 발생한 원인장소로는 일반음식점에서의 음식 섭취가 37.2%로 가장 높게 나타났고, 가정에서의 부주의가 21.2% 등으로 나타났으며, 원인식품으로는 고기 등의 육류 및 가공품이 41.7%, 생선 등 어패류 및 가공품이 18.7% 등으로 나타났다. 식중독 원인균에 대한 인식에서는 콜레라(75.5%), 비브리오(73%), 이질(65.5%), 장티푸스(51.8%), 살모넬라증(47.5%)의 순으로 잘 알고 있는 것으로 나타났지만 리스테리아증(9.9%), 브루셀라중(8.3%)에 대해서는 대부분이 모르거나 음식물로 인해 발생하지 않는 것으로 인식하고 있는 것으로 나타났다. 한편, 조사자료를 바탕으로 3가지 모델로 구분 즉, Model 1은 식중독 원인균에 대한 지식, Model 2는 식품안전에 대한 인식, Model 3은 식중독 예방을 위한 행동에 대한 인식으로 구분하였고, 각 모델들은 조사자의 일반사항에서 나타난 변수와 식중독 경험여부 별로 다중회귀분석(Multiple regression analysis)을 수행하였다. 그 결과 식중독 원인균에 대한 인식(Model 1)은 여러 변수 중 교육수준(OR 0.536), 결혼상태(OR 0.529)가 영향요인으로 나타났으며, 특히, 과거 식중독 경험이 가장 중요한 영향요인으로 나타났다(OR 1.714). 식품안전에 대한 인식(Model 2)에서는 교육수준이 중요한 영향요인으로 나타났으며(OR 0.702), 식중독 예방을 위한 행동에 대한 인식(Model 3)에서는 교육수준(OR 0.816)과 성별(OR 0.650)이 중요한 영향으로 나타났으며, 과거 식중독 경험이나 식품안전에 대한 인식정도는 식중독 예방을 위한 행동에 대한 인식과는 상관관계가 없는 것으로 나타났다. 결론적으로 식품안전에 있어 경험과 지식은 실제 식중독 예방을 위한 행동에는 크게 영향을 미치지 않음을 의미하는 것으로 볼 수 있다. The purpose of this study was to investigate the awareness and practice of Korean consumer on food safety. A telephone survey was conducted from 1,040 adults randomly selected from each province and large city of Korea. Therefore, 12.4% of the subjects experienced foodborne illness at least once a year and 0.3% was hospitalized due to the illness. General restaurant (37.2%) and home (21.2%) were the main causative place of foodborne illness, and the most frequently associated foods were meat and meat products (41.7%) and fish and fish products (18.7%). Regarding the causative agent of foodborne illness, the respsondents were aware of Cholera (75.5%), Vibrio gastroenteritis (73%), Shigellosis (65.5%), Bacillary dysentery (65.5%) and Salmonellosis (47.5%) very well; however very few were aware of Listeriosis (9.9%) and brucellosis (8.3%) and ever believed they were not food-related illness. When the survey data were analyzed based on 3 models (Model 1: Knowledge about the pathogens associated food and water, Model 2: The awareness of food safety, Model 3: Attitudes and behavior about foodborne disease prevention and measure) by Multiple regression analysis. The results showed that the awareness of the causative agent of foodborne illness was significantly related with the previous experience of foodborne illness (OR: 1.714) followed by education level (OR: 0.536) and married status (OR: 0.527). The awareness of food safety was significatly related with education level (OR: 0.702). Education (OR: 0.816) and gender (OR:0.650) were the main factors affecting the awareness of the practice to prevent foodborne illness. However, the previous experience of foodborne illness and food safety education, and the awareness of food safety did not show any correlation, suggesting that the experience and awareness of foodborne illness do not affect the real practice of food safety.

최적화를 이용한 전기자동차 구조물 접합부의 특성 규명

박경진(Gyung-Jin Park),이광원(Kwang Won Lee),박영선(Kweon Hee Lee),이권희(Young Sun Park),김만식(Mahn-Shik Kim),이용래(Yong-Rae Lee),정태은(Tae-Eun Chung) 한국자동차공학회 1995 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1995 No.11_1

Recently, electric vehicles have been developed in many places for various reasons. Although the stick model with beam clements is very convenient for the analysis and design, it may have significant errors due to the considerable simplifications. Especially, the difficulties exist at the modeling of joints, since the joints have complicated characteristics. In this research, a method for the joint modeling is suggested and verified. Beam elements are defined around a joint in the finite element analysis. The section properties of the joint elements are tuned to generate target responses by optimization. The target values are calculated by experiments or detailed analysis. The evaluated joints are be inserted in the full car model of an electrical vehicle.<br/>

[특집 신제품개발프로세스] 공리적 설계

박경진(Gyung-Jin Park),강병수(Byung-Soo Kang) 한국자동차공학회 2005 오토저널 Vol.27 No.1

김밥에서의 Staphylococcus aureus에 대한 정량적 미생물위해평가 모델 개발

박경진(Gyung-Jin Bahk),오덕환(Deog-Hwan Oh),하상도(Sang-Do Ha),박기환(Ki-Hwan Park),정명섭(Myung-Sub Joung),천석조(Suk-Jo Chun),박종석(Jong-Seok Park),우건조(Gun-Jo Woo),홍종해(Chong-Hae Hong) 한국식품과학회 2005 한국식품과학회지 Vol.37 No.3

구조최적설계시 근사법의 정확도를 이용한 이동한계 전략의 개발

박영선,박경진,Park, Young-Sun,Park, Gyung-Jin 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.8

The move limit strategy is used to avoid the excessive approximation in the structural optimization. The size of move limit has been obtained by engineering experience. Recently, efforts based on analytic methods are performed by some researchers. These methods still have problems, such as prematurity or oscillation of the move limit size. The existing methods usually control the bound of design variables based on the magnitude. Thus, they can not properly handle the configuration variables based on the geometry in the configuration optimization. In this research, the size of move limit is calculated based on the accuracy of approximation. The method is coded and applied to the two-point reciprocal quadratic approximation method. The efficiency is evaluated through examples.

공리적 설계를 이용한 온라인전기자동차의 설계분석

김진호(Jin-Ho Kim),홍을표(Eul-Pyo Hong),박경진(Gyung-Jin Park) 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.11

On-Line Electric Vehicle is a new concept of electric vehicle. The On-Line Electric Vehicle overcomes problem of conventional electric vehicle by using contactless power transmission technique and the vehicle has now been developing at KAlST. In the early stage of product development. the design process can be inefficient and lime-consuming if there is no proper design process. To develop the on-line electric vehicle. an appropriate design process is also required. Functional requirements. design parameters and design matrices of the vehicle are defined and the design hierarchy is also established up to the level of sub-systems. Axiomatic design theory is utilized 10 propose the appropriate design process of the on-line electric vehicle and the Independence Axiom is utilized to investigate design characteristics of the vehicle. The appropriate design process is proposed based on the design hierarchy to make the design process of the Oil-Line Electric Vehicle more efficient and systematic.

등가정하중과 관성제거를 이용한 차량 전면 구조물 충돌 최적설계

안진석(Jin-Seok Ahn),이영명(Youngmyung Lee),박경진(Gyung-Jin Park) 한국자동차공학회 2014 한국자동차공학회 학술대회 및 전시회 Vol.2014 No.11

벨로우즈에 대한 유한요소해석 프로그램 및 간편식의 개발과 형상최적설계

고병갑,박경진,Koh, Byung-Kab,Park, Gyung-Jin 대한기계학회 1997 大韓機械學會論文集A Vol.21 No.8

Bellows is a component in piping systems which absorbs mechanical deformation with flexibility. Its geometry is an axial symmetric shell which consists of two toroidal shells and one annular plate or conical shell. In order to analyze bellows, this study presents the finite element analysis using a conical frustum shell element. A finite element analysis is developed to analyze various bellows. The validity of the developed program is verified by the experimental results for axial and lateral stiffness. The formula for calculating the natural frequency of bellows is made by the simple beam theory. The formula for fatigue life is also derived by experiments. The shape optimal design problem is formulated using multiple objective optimization. The multiple objective functions are transformed to a scalar function by weighting factors. The stiffness, strength and specified stiffness are considered as the multiple objective function. The formulation has inequality constraints imposed on the fatigue limit, the natural frequencies, and the manufacturing conditions. Geometric parameters of bellows are the design variables. The recursive quadratic programming algorithm is selected to solve the problem. The results are compared to existing bellows, and the characteristics of bellows is investigated through optimal design process. The optimized shape of bellows is expected to give quite a good guideline to practical design.

강건성을 고려한 공리적 설계의 새로운 정보 지수

황광현,박경진,Hwang, Kwang-Hyeon,Park, Gyung-Jin 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.10

In product design and manufacturing, axiomatic design provides a systematic approach for the decision-making process. Two axioms have been defined such as the Independence Axiom and the Information Axiom. The Information Axiom states that the best design among those that satisfy the independence axiom is the one with the least information content. In other words, the best design is the one that has the highest probability of success. On the other hand, the Taguchi robust design is used in the two-step process; one is "reduce variability," and the other is "adjust the mean on the target." The two-step can be interpreted as a problem that has two FRs (functional requirements). Therefore, the Taguchi method should be used based on the satisfaction of the Independence Axiom. Common aspects exist between the Taguchi method and Axiomatic Design in that a robust design is induced. However, different characteristics are found as well. The Taguchi method does not have the design range, and the probability of success may not be enough to express robustness. Our purpose is to find the one that has the highest probability of success and the smallest variation. A new index is proposed to satisfy these conditions. The index is defined by multiplication of the robustness weight function and the probability density function. The robustness weight function has the maximum at the target value and zero at the boundary of the design range. The validity of the index is proved through various examples.gh various examples.