• 농업과학연구
• /
• 제43권1호
• /
• pp.144-151
• /
• 2016

With an aging population in rural areas, farm owners in South Korea are also aging. In particular, this phenomenon leads to the lack of human resources in rural areas and agriculture, worsening the deterioration of the rural economy. This study aimed, firstly, to analyze the criticality of the lack of human resources and high production cost issues for farmers, before using the farm as cooperative nursery of rice seedlings. Secondly, the study analyzed farmer satisfaction after using the farm cooperative. Analysis results are as follows. The motives of the research subjects for using the co-nursery were the aging of the farming population, the expected reduction of production costs, and farmers' failure in raising seedlings. Importance-performance analysis measured the importance for the farms for cooperative raising of rice seedling at 3.49 and the performance for the farms at 3.41, with a difference of 0.07 between them. The four importance-performance matrix areas, used were as follows: concentrated efforts required (Quadrant I: concentrate here), continuous maintenance (Quadrant II: keep up the good work), gradual improvement (Quadrant III: low priority), and avoiding excessive efforts (Quadrant IV: possible overkill). Based on the results, it was concluded that improvements and efforts would be necessary for each of these areas. And, there is a need to improve services through the initiation of farmer use of this rice co-nursery.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2003년도 추계학술대회논문집
• /
• pp.97-100
• /
• 2003

Globally, the various machine components, as in electronics and communications, are demanded to being high-performance and micro-scale with abrupt development of the fields of computers, mobile communications. As this current tendency, production of the parts that must have high accuracy, so called milli-structure, are accomplished by the method of top-down, differently as in the techniques of MEMS, NANO. But, in the case of milli-structure, production procedure is highly costs, difficult and demands more accurate dimension than the conservative forming, processing technique. In this paper, forming analysis of the micro-former as the milli-structure are performed and then calculate the punch force etc. This information calculated is applied to decide the forming capacity of micro-former and design the process of forming stage, dimension of dies in another forming bodies. And, for the better precise forming analysis, elasto-plastic analysis is to be performed, then the consideration about effect of elastic recovery when punch and die are unloaded, have to be discussed in change of dimensions.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제11권1호
• /
• pp.78-101
• /
• 2017

High-quality industrial control is critical to ensuring production quality, reducing production costs, improving management levels and stabilizing equipment and long-term operations. WiFi-based Long Distance (WiLD) networks have been used as remote industrial control networks. Real-time performance is essential to industrial control. However, the original mechanism of WiLD networks does not minimize end-to-end delay and restricts improvement of real-time performance. In this paper, we propose two algorithms to obtain the transmitting/receiving phase cycle length for each node such that real time constraints can be satisfied and phase switching overhead can be minimized. The first algorithm is based on the branch and bound method, which identifies an optimal solution. The second is a fast heuristic algorithm. The experimental results show that the execution time of the algorithm based on branch and bound is less than that of the heuristic algorithm when the network is complex and that the performance of the heuristic algorithm is close to the optimal solution.

• 드라이브 ㆍ 컨트롤
• /
• 제20권4호
• /
• pp.107-114
• /
• 2023

Garlic is one of the major seasoned vegetables in Korea along with peppers and onions. Although it is a major cash crop, the aging population of farmers and rising labor and production costs are cited as the reasons for the decreasing production. Accordingly, it is necessary to introduce and spread garlic cultivation mechanization technology to reduce the input labor demand. In this study, conducted a field demonstration in Jeollanam-do using garlic harvesting machinery. In addition, it was intended to improve the mechanization rate of garlic harvesting by deriving factors that can apply to garlic harvesting machines in Jeollanam-do and investigating regional adaptability. As a result of the analysis, it was found that the harvesting performance of the garlic harvester and garlic collector in Jeollanam-do met the agricultural machine test standards. In addition, as a result of calculating the input effect of the mechanized work system compared to the conventional garlic harvesting work system, it was found that there was a labor-saving effect of 96.02%.

• 수산해양기술연구
• /
• 제49권3호
• /
• pp.291-300
• /
• 2013

The main purpose of this study is to analyse economic feasibility of low-carbon-oriented gear for anchovy boat seine. The results of benefit/cost analysis showed that use of the low-carbon fishing gear is economically feasible. Considering the fuel saving and relatively low $CO_2$ emission by reducing the resistance of gear, net present value by such type 1 gear improvement was estimated about -2,490 ~ -1,580 million won with the benefit-cost ratio 0.81~ 0.88. And net present value by such type 2 gear improvement was estimated about 6,540 ~ 7,780 million won with the benefit-cost ratio 1.79 ~ 1.94. Development of lowcarbon trawl gear would render significant contributions to reducing $CO_2$ emission in fishing operations and lead to reduce fishing costs due to fuel savings.

• Journal of Microbiology and Biotechnology
• /
• 제26권5호
• /
• pp.854-866
• /
• 2016

The production cost of biodiesel from microalgae is still not competitive, compared with that of petroleum fuels. The genetic improvement of microalgal strains to increase triacylglycerol (TAG) accumulation is one way to reduce production costs. One of the most promising approaches is the isolation of starch-deficient mutants, which have been reported to successfully increase TAG yields. To date, such a stable mutant is not available in an oleaginous marine microalga, despite several advantages of using marine species for biodiesel production. Algae in the genus Dunaliella are known to tolerate high salt concentration and other environmental stresses. In addition, the cultivation processes for large-scale outdoor commercialization have been well established for this genus. In this study, Dunaliella tertiolecta was used to screen for starch-deficient mutants, using an iodine vapor-staining method. Four out of 20,016 UV-mutagenized strains showed a substantial reduction of starch content. A significantly higher TAG content, up to 3-fold of the wild-type level, was observed in three of the mutants upon induction by nitrogen depletion. The carotenoid production and growth characteristics of these mutants, under both normal and oxidative stress conditions, were not compromised, suggesting that these processes are not necessarily affected by starch deficiency. The results from this work open up new possibilities for exploring Dunaliella for biodiesel production.

• 수산해양기술연구
• /
• 제57권4호
• /
• pp.316-333
• /
• 2021

In order to understand basic data for improving the fishing system and fishing vessel structure in coastal improved stow net fishery, a questionnaire survey and on-site hearing were conducted from May 10 to June 11, 2019 to analyze opinions on the improvement of operation status and fishing vessel structure. The questionnaire survey consisted of ten questions on the operation status of coastal improved stow net fishery and six questions on the improvement of fishing vessel structure, and the results of each question were analyzed by the region, the captain's age, the captain's career and the age of fishing vessel. As a result of analyzing opinions on the operation status of the coastal improved stow net fishery, it was found that the average time required for casting net was 32.8 to 33.0 minutes and that the average time required for hauling net was 41.0 to 42.2 minutes which took 10 to 12 minutes more than for casting net. The most important work requiring improvement during fishing operation (the first priority) were 'hauling net operation,' 'readjustment and storage of fishing gear,' and 'fish handling' and the hardest factor in fishing management were in the order of 'reduction of catch,' 'labor shortage' and 'rising labor costs.' The most institutional improvement that is most needed in coastal improved stow net fishery was an 'using fine mesh nets.' Most of the respondent to the questions on the experience in hiring foreign crews was 'either hiring or willing to hire foreign crews,' and the average number of foreign crews employed was found to be 2.3 to 2.4 persons. The most important reason for hiring (or considering employment) foreign crews was 'high labor costs.' The degree of communication with foreign crews during fishing operation were 'moderate' or 'difficult to direct work.' The most important problem in hiring foreign crews (the first priority) was an 'illegal departure.' As the survey results on the opinion of structural improvement of coastal improved stow net fishing vessel, the degree of satisfaction with fishing vessel structure related to fishing operation was found to be somewhat unsatisfactory, with an average of 3.3 points on a five-point scale. The inconvenient structure of fishing vessel in possession (the first priority), the space needed most for the construction of new fishing vessel (the first priority) and the space considered important for the construction of new fishing vessel (the first prioprity) was a 'fish warehouse.' The most preferred equipment for the construction of new fishing vessel were 'engine operation monitoring' and 'navigation safety devices.' The average size (tonnage class), the average horse power and the average total length of fishing vessel for proper profit and safety fishing operation was between 13.8 and 14.0 tonnes, 808.3 to 819.5 H.P. and 23.4 to 23.5 meters, respectively. The results of the operation status of coastal improved stow net fishery and the requirement for improving the fishing vessel structure are expected to be provided as basic data for reference when we build or improve the fishing vessel.

• 한국중재학회지:중재연구
• /
• 제27권2호
• /
• pp.59-81
• /
• 2017

The purpose of this study is to find a solution to disputes in the process of producing digital music sources. At present, the center of the world music market including the domestic market has been completely transformed from the tangible musical record market to the intangible sound source market. Due to these environmental changes, the music production process becomes industrialized and specialized, causing conflicts of interest among the individuals in the process. First of all, this study examined changes in the music market which is the background of the dispute, identified the problems of the process and suggested solutions while summarizing the meaning and role of each process of producing a sound source that may arise during the sound production process. This study covers plagiarism between producers, copyright infringement of the creator against assistant creator caused by the industrialization and division of the production environment, issues related to the rights of sound engineers whose role and importance become bigger as acoustic technology develops and music genres become more diverse, and vertical hierarchy due to the formation of oligopoly by several distributors with huge capital. As a result of the study, it was concluded that Alternative Dispute Resolution (ADR) system is suitable for solving these problems. Specific methods of using ADR include activation of the dispute settlement system of the Korea Copyright Commission, active use of the arbitration clause specified in the standard contract, and recalculation of labor costs and earnings from copyright through mutual negotiations. This paper can be differentiated from previous studies in that it studied overall problems that might arise in the process of digital music source production and suggested ADR utilization as the solution.

• 농업과학연구
• /
• 제10권2호
• /
• pp.371-381
• /
• 1983

This study is aimed at identifying the economic effects of drainage improvement projects. The total area of poor drainage is equivalent to 170,000ha, 13% of the total area of paddy field in Korea. The development of poor drained paddy is an urgent problem considering the low rate of self-sufficiency of food grain and the limitation of farmer's income increase. Rapid development of Korean economy has brought labor shoriage in rural farming sector. Accordingly farm mechanization is an important agricultural policy to hike labor productivity and to save production costs of rice farming. The expected economic benefits of the drainage improvement project are derived from increasing land productivity, expanding double cropped area and farming the farm mechanization base in paddy fields. The economic and financial rate of return of the project are considered very important decision making criteria for project implementation by resource allocation. Therefore this study covered benefit and cost analysis of the sampled area, the estimated financial rate of returns in $Buy{\check{o}}$ and Jinsung are represented 15% and 51% respectively and the economic rate of returns in both project area are also showing 1% and 26% respectively. The rate of return of the projects has showed an outstanding variance according to the locational and natural characteristics of the project area. As showing the above economic rate of return, $Buy{\check{o}}$ is very low Jinsung is very high. But the financial rate of return of both projects are considered comparatively high. Cosequently, the drainage improvement projects should be promoted from the view point of farm income increase to make narrow the income gap between rural and urban incomes and farm mechanization to solve labor shortage in the rural area.

• 한국산학기술학회논문지
• /
• 제21권3호
• /
• pp.321-327
• /
• 2020

최근 2년간 군 기동화력장비의 엔진 생산 공정 중에 발생한 주요 품질문제 중에는 엔진오일 누유가 가장 많은 비중을 차지하고 있다. 이를 최소화하기 위해서는 엔진오일 누유에 대한 근본적인 원인 파악과 다빈도로 발생되는 누유 부위에 대한 파악이 필요할 뿐만 아니라 더 나아가 품질비용 감소를 위해서는 엔진 조립 및 검사공정에서 누유에 대한 사전식별이 필요하다. 본 연구에서는 형광염료가 주입된 엔진오일을 통하여 누유를 가시화하고 엔진오일 누유 현상에 대한 식별성을 증대시켜 군 기동화력장비 엔진의 생산품질을 향상시키고자 하였다. 이를 위하여 기존에 사용하는 엔진오일과 형광염료가 주입된 엔진오일의 특성분석을 통하여 대체 가능성에 대해 검토하였으며 엔진오일 주입 공정과 누유검사 공정을 개선하여 엔진오일 누유에 의하여 발생할 수 있는 정비기간 및 시간을 최소화 시키고자 하였다. 최종적으로 본 연구결과를 토대로 군 기동화력장비 엔진의 신뢰도 확보 및 엔진 생산업체의 품질관리 능력 향상을 통하여 엔진 생산 공정간 발생할 수 있는 품질비용을 최소화 시킬 수 있다고 사료된다.