Fish samples were collected by a set net from April to December 2020 at the coastal waters off Tongyeong, Korea to determine fish species composition and seasonal variation. A total of 330,675 fish (1,032,578 g) representing 56 species belonging to 39 families were collected during the sampling period. The dominant species were Engraulis japonicus, Trachurus japonicus and Trichiurus japonicus, which accounted for 98.1% of the total number of individuals and 87.5% of the total biomass collected. E. japonicus and Chelidonichthys spinosus appeared every month off the coast of the Tongyeong. Cluster analysis based on the number of individuals of fish were classified into two groups at the dissimilarity level of 57%, and the results of ANOSIM analysis revealed significant differences in community structure among the two groups

CFRP materials are one of the excellent lightweight materials of the next generation. Also, the CFRP materials are attracting materials form the global automotive industry. However, CFRP material is made at a high cost of carbon fiber as raw material, so research of production cost reduction into the development of molding equipment and molding process technology related to mass production for the automotive industry is actively administered. Generally, CFRP is known as a high corrosion-resistant material in which no corrosion occurs. However, the investigation of the relationship with corrosion behavior on the roughness of CFRP's conditions according to is rarely studied. In this paper, the surface roughness has conducted three surface roughness conditions given arbitrarily, and the electrochemical evaluation has performed under the electrolysis conditions of 5 wt.% NaCl, which is the salt-water test condition of vehicle parts in automotive industries. Moreover, the samples were analyzed with changes of microstructures by FE-SEM and chemical composition's variation by EDS before and after electrochemical evaluation.

In this study, we analyzed the factors affecting the introduction of Smart Factory by domestic SMEs through AHP analysis and tried to provide implications for the introduction of Smart Factory. It was confirmed that the manufacturing and introduction group, the non-manufacturing introduction group, and the already introduced group had the highest weight in the cost reduction in the first hierarchy standard. At this time, it can be seen that the weight for cost reduction is relatively high in the manufacturing introduction group and the introduction group, and the weight for the productivity improvement is relatively high in the non-manufacturing introduction group. It can also be seen that the portion of marketing enhancement does not have a significant impact on smart factory choices. It was confirmed that image enhancement is the highest in the manufacturing introduction group and the non-manufacturing introduction group in the first hierarchy standard, and the marketing has the highest weight in the introduction group. In the two - tiered standard, customer - friendly and proper inventory maintenance weights were relatively high in all the introduced groups, except for the high rankings.

Aluminum alloys are the light weight materials, they are commonly used in many industrial applications such as electronic, aerospace, automotive, and medical industry. Because they are used in these such applications. Therefore, their light weight and high surface quality are required. In this paper, the surface improvement round flat aluminum alloy using lapping finishing method was explored. In order to find the optimal condition, lapping parameters such as, rotational speeds, abrasive grain sizes of pad, processing times, and lapping oils were investigated in this study. The improvement in surface roughness was found to be highest with optimal condition at 200 rpm of rotational speed, 1 ㎛ abrasive grain size of pad, 0.5ml of light oil for 720 sec. By using the optimal condition, the initial surface roughness Ra of round flat aluminum alloy can be enhanced from 2.59㎛ to 0.02 ㎛. This can be concluded that the small CNC machine with lapping finishing method can be used to enhance the surface roughness of round flat aluminum alloy effectively.

Magnetic abrasive finishing (MAF) process is a surface improvement method, which the magnetic field of permanent magnet or electromagnet is used to control the abrasive particles during the finishing process. The magnetic abrasive tools are filled between the N-pole and S-pole of Nd-Fe-B type permanent magnets. Tungsten carbide bar (WC) is a high hardness material and its compressive strength is much higher than the other materials. Therefore, due to its superior mechanical properties, it has been widely used in cutting or machining process. Because the smooth surface of tungsten carbide is required in cutting tools, thus the magnetic abrasive finishing process was applied for achieving its surface accuracy and dimensional accuracy. The results showed that the surface roughness of tungsten carbide bar was improved from Ra: 0.23㎛ to Ra: 0.02㎛ in 120 sec by magnetic abrasive finishing process.

This study was successfully achieved out the optimized system for dispersing and mixing condition of resin liquid. The flow analysis was simulated according to the shape of the impeller and the stirring tank using ANSYS software and optimized in advanced design. As a result, it was confirmed that the shape and double number of the impeller on the flow field are influenced better effects in a range of mixing and diffusion areas comparing to single number of impeller. It was considered that stirring was performed more quickly and efficiently under the condition of double numbers and saw tooth type impeller. This result can be applied practically for the mixing tank in the industrial application and avaliable used to make a new system for painting equipment.

To improve life time of machine components, higher alloy grade materials are used by adding more metal alloy components and content. Also production processes are further complicated and subdivided such as the forging, preliminary heat treatment, quality heat treatment, rough machining and finished machining process. Those reasons become major cause of large stress in the materials, and the residual stress generated during the manufacturing process causes fatal defects, such as crack, surface tear, warping and deformation of the products. It is necessary to evaluate the residual stress on the entire processes, from forging process to final finished machining process. Also in order to avoid those problems caused by residual stresses, it is necessary to know in advance what process is important to be controlled and what parameters affect residual stress. By the hole drilling method, residual stress was measured in each manufacturing process step. In this study, the hardness of the surface, the cutting force test and the metal analysis were performed to clarify the influence of manufacturing process parameters.

본 연구는 참여를 통해 일어나는 감정적 반응인 즐거움을 통해 조합원과 생활협동조합의 조직성과와 의 구조적 관계를 매력성, 지속적 정보탐색 및 호혜성이라는 매개변수를 통해 검증하고자 한다. 본 연구의 결과 첫 본 연구에서는 플로우(Flow)이론에 입각하여 참여와 참여를 통한 즐거움이 조합원 의 몰입을 이끌어 내고 이러한 몰입을 통해 생활협동조합원들은 생활협동조합 제품에 대한 매력성을 지 각하게 되면 상호 호혜성, 충성도 및 관계지속성에 긍정적인 영향을 미친다는 것이 가설(H1,H2,H5,H7,H8,H9) 을 통해 검증되었으며, 참여를 통해 참여 즐거움을 느낀 조합원들은 제품 과 생활협동조합에 대한 지속적인 정보탐색을 한다는 것은 가설(H1,H2,H3)로 검증이 되었고 또한 이런 조합원들 생활협동조합 제품에 대한 매력성을 통해서도 또 다른 정보탐색에 대한 욕구가 생기고 더욱 더 생활협동조합과 관련된 정보를 지속적으로 탐색하려고 한다는 것을 가설(H4)를 통해서 지지되었다. 하지만, 생활협동조합의 조합원들이 참여를 통해 즐거움을 느끼게 되면 좀 더 생활협동조합과 관련된 정보를 탐색하려 하고 또한 친환경제품 에 대한 관심도 더욱 가지게 되면서 생활협동조합 제품에 대한 지속적인 정보탐색을 한다는 것은 앞선 가설에서 검증되었지만 이러한 지속적 정보탐색을 통해 생활협동조합에 대한 상호 호혜성 지각 혹은 생 활협동조합에서 조합원으로 활동하고 있는 조합원들에 대한 상호 호혜성 지각은 일어나지 않는 것으로 가설(H6)에서 보여주고 있다. 이는 본 연구에서 중요한 시사점을 제공한다고 할 수 있다. 유기농 제품 사용의 중요성 혹은 친환경제품에 대한 중요성을 지각한 소비자들이 생활협동조합에 조합원으로 참여하 여 생활협동조합의 제품을 구매하려고 하지만 각각의 조합원들의 개인특성과 개인이 추구하는 목적에 따라 다르게 나타난다는 것이다.

450KHz 저주파수로 플라즈마 화학증착법을 이용하여 Diamondlike carbon박막을 제작하고 optical band gap, 미소경도, 내부응력 등의 물성에 대하여 13.56MHz의 전원을 사용했을 때보다 optical band gap이 감소하였으며 FT-IR및 CHN분석결과 박막 내의 C-H결합농도와 총 수소의 함량이 크게 감소하는 것으로 밝혀졌다. 또한 저주파수로 DLC 박막을 형성하는 경우 미소경도의 희생없이 내부응력을 크게 줄일 수 있어 기판과의 접착성이 향상될 것으로 기대되었다.