• 제목/요약/키워드: 경남대학교

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Thrichoderma atroviride 배양액의 tyrosinase 억제제에 관한 연구 (Inhibition of Tyrosinase by Metabolites Originating from Thrichoderma atroviride)

  • 강동우;김규민;김예성;서유진;송다영;오다윤;최시온;황주현;김삼웅;방규호;갈상완
    • 생명과학회지
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    • 제31권1호
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    • pp.47-51
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    • 2021
  • 현대인에게 미백화장품은 미를 나타내는 중요한 요소이다. 균류는 미백에 연관된 다양한 물질대사산물을 생산한다. 본 연구에서 미백기능성 화장품에 소재를 탐색하기 위해 Trichoderma atroviride 배양액에 물질대사산물에 의한 tyrosinase inhibitors를 조사하였다. 또한, 억제 효과는 식의약안전처에 미백화장품 원료로 승인된 알부틴과 비교하였다. T. atroviride 배양액에 물질대사산물은 알부틴의 활성보다 높은 tyrosinase 억제 활성을 보였다. T. atroviride 배양액에 포함된 tyrosinase inhibitors 중 일부는 열에 안정한 반면에, 일부는 열에 불안정하였다. 본 물질들은 약산성~중성 pH 영역에서는 안정하였지만, 그 외 영역에서는 매우 불안정하였다. Proteinase K에 의해 활성 영향이 거의 없었기 때문에 inhibitor들은 대부분 물질대사산물로 구성된 것으로 추정된다. 따라서 본 T. atroviride 배양액에 물질대사산물은 미백화장품 소재로써 잠재적 가치가 있는 것으로 제의된다.

버블을 이용한 미세칩 제거장치의 개발 (Development of Micro-chip Removal Equipment Using Bubble)

  • 최성윤;권대규;이세한;박태현;왕덕현
    • 한국기계가공학회지
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    • 제20권10호
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    • pp.88-94
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    • 2021
  • Machining operations require the removal of chips to keep the water-soluble cutting oil clean and fresh throughout the operation time. Water-soluble cutting oil for metal processing is diluted using a 3-8% solution in water which is generally replaced every three to six months. This study aims to develop multiple purification devices to efficiently remove fine contaminating particles from water-soluble cutting oil. The 2D concept designs were created using AutoCAD. The designs were drawn using the 3D modelling feature of CATIA. Flow analysis was performed in a bubble purifier using Ansys computational fluid dynamics (CFD). This analysis has aided in improving the design and structure of the device to create the final prototype. Experiments were conducted to check the prototype's performance. Comparisons of the effects of each process variable on the experiment was carried out using ANOVA.

볼 엔드밀에 의한 경사면 상방향 절삭가공에 관한 연구 (Study on Upward Machining of Inclined Surface by Ball-End Milling)

  • 정진우;배은진;김상현;왕덕현
    • 한국기계가공학회지
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    • 제20권4호
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    • pp.87-93
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    • 2021
  • The mold industry is competitive, and mold should be processed under optimal conditions for efficient processing. However, the cutting conditions of the ball-end mill, which are a major factor in mold processing, are mostly set empirically, and considerable research is required for increasing the tool life and processing accuracy. In this study, a tool dynamometer and an eddy current sensor were used along with NI-DAQ, a data acquisition device, to obtain characteristic values of the cutting force and tool deformation during the ball end-mill machining of inclined surfaces at a machining center. The cutting force and tool deformation were measured in an experiment. It was found that the tool received the greatest cutting force at the end of the machining process, and the deformation of the tool increased rapidly. Furthermore, the cutting force tended to increase with the angle and number of rotations. The deformation increased rapidly during the machining of a 45° inclined surface.

스마트 팩토리를 위한 제조공정 내에서 단조 부품의 이송자동화를 위한 로봇의 실시간 경로제어에 관한 연구 (A Study on the Real-Tim Path Control of Robot for Transfer Automation of Forging Parts in Manufacturing Process for Smart Factory)

  • 강정석;노성훈;김두범;배호영;김상현;임오득;한성현
    • 한국산업융합학회 논문집
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    • 제22권3호
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    • pp.281-292
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    • 2019
  • This paper proposed a new technology to control a path forging parts in limited narrow space of manufacturing process automation for smart factory. In the motion control, we adapted the obstacle avoidance technology based on ultrasonic sensors. The new motion control performance test for a mobile robot is experimented in narrow space environments. The travelling path control is performed by a fuzzy control logic. which plays a role for selecting an appropriate behavior in accordance with the situation in the vicinity of the mobile robot. Ultrasonic sensors installed at the front face of the mobile robot are used. In order to update the current position and heading angle of the mobile robot, a new approch is adapted. The reliability is illustrated by simulation and experiments.

스마트 팩토리를 위한 제조공정내에서 모바일 로봇의 장애물 회피 및 자율주행에 관한 연구 (A Study on Obstacle Avoidance and Autonomous Travelling of Mobile Robot in Manufacturing Precess for Smart Factory)

  • 김두범;김희진;문정철;배호영;한성현
    • 한국산업융합학회 논문집
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    • 제21권6호
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    • pp.379-388
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    • 2018
  • In this study, we propose a new approach to impliment autonomous travelling of mobile robot based on obstacle avoidance and voice command. Obstacle Avoidance technology of mobile robpot. It has been used in wide range of different robotics areas to minimize the risk of collisions. Obstacle avoidance of mobile robots are mostly applied in transportation systems such as aircraft traffic control, autonomous cars etc. Collision avoidance is a important requirement in mobile robot systems where they all featured some kind of obstacle detection techniques in order to avoid colliding. In this paper it was illustrated the reliability of voice command and obstacle avoidance for autonomous travelling of mobile robot with two wheels as the purpose of application to the manufacturing process by simulation and experiments.

볼엔드밀 공구에 의한 사각형상 가공시 공구 휨에 따른 절삭력 특성 (Cutting Force Characteristics and Tool Deflection When Machining Rectangular Shapes with a Ball End Mill)

  • 김인수;김상현;이동섭;왕덕현
    • 한국기계가공학회지
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    • 제18권6호
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    • pp.26-32
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    • 2019
  • Ball end mills used for high-speed and high-precision machining require longer machining time than flat end mills or face cutters, since the tool diameter is limited and the rigidity is reduced by the characteristics of the tool's cutting edge: at the top end of the tool, the cutting speed approaches zero and hardly removes any material. Because there is little material removal at the top end of the ball end mill, the outer cutting edge performs the majority of the work; this irregular cutting force deforms the tool and shortens its life. In this study, we attached an eddy-current sensor to a tool to measure the deformation from the cutting force and we used a tool dynamometer to measure the cutting force. We found that the change in cutting force is dependent on the change in feed rate during square-shaped processing and, as the feed rate is accelerated, the cutting force also increases. Higher cutting forces increase tool deformation.

간호대학생의 의약품 자가투약 실태, 약물에 대한 지식 및 태도에 관한 연구 (Knowledge and Attitude about Drugs and the Current Status of Self-medication of Nursing Students)

  • 김혜옥;이은주;성민;김민경
    • 의료커뮤니케이션
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    • 제13권2호
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    • pp.185-193
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    • 2018
  • Background: Nursing college students are exposed to information about diseases or drugs, and are likely to have a distorted perception of drug knowledge or behavior. The study aimed to identify knowledge and attitude about drugs and current status of self-medication among nursing students. Methods: The subjects were 172 nursing students from a university in Busan. Data were collected with structured questionnaires and analyzed using descriptive analysis, t-test, and one-way ANOVA using SPSS 23.0. Results: Nursing students had a high level of knowledge about drugs, but attitudes toward drugs were relatively low. 83.7% of patients had experience of self-medication. The methods to acquire information for self-administration were 29.9% by smart phone and 27.1% by internet. The use of nonsteroidal anti-inflammatory drugs (NSAIDs) among self-medication drugs was the highest. The most common reason for self-medication was 'I thought it to be a mild disease', and the pharmacists were the most affected by choice of self-medication. The knowledge about drugs was statistically significant according to grade, school life satisfaction and subjective health status. The attitudes about medication were statistically significant according to grade and self-medication experience. Conclusion: Nursing college students need drug safety education to improve awareness and practice of correct drug use.