• International Journal of Ocean System Engineering
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• 제2권2호
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• pp.116-138
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• 2012

As in the other fields of mechanics, analytical methods represent an important analysis tool in marine hydrodynamics. The analytical approach is interesting for different reasons : it gives reference results for numerical codes verification, it gives physical insight into some complicated problems, it can be used as a simplified predesign tool, etc. This approach is of course limited to some simplified geometries (cylinders, spheres, ...), and only the case of one or more cylinders, truncated or not, will be considered here. Presented methods are basically eigenfunction expansions whose complexity depends on the boundary conditions. The hydrodynamic boundary value problem (BVP) is formulated within the usual assumptions of potential flow and is additionally simplified by the perturbation method. By using this approach, the highly nonlinear problem decomposes into its linear part and the higher order (second, third, ...) corrections. Also, periodicity is assumed so that the time dependence can be factorized i.e. the frequency domain formulation is adopted. As far as free surface flows are concerned, only cases without or with small forward speed are sufficiently simple to be solved semi-analytically. The problem of the floating body advancing in waves with arbitrary forward speed is far more complicated. These remarks are also valid for the general numerical methods where the case of arbitrary forward speed, even linearized, is still too difficult from numerical point of view, and "it is fair to say that there exists at present no general practical numerical method for the wave resistance problem" [9], and even less for the general seakeeping problem. We note also that, in the case of bluff bodies like cylinders, the assumptions of the potential flow are justified only if the forward speed is less than the product of wave amplitude with wave frequency.

• 한국항해항만학회지
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• 제45권2호
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• pp.61-68
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• 2021

Logistics movement using ships has been used for many centuries, but maritime accidents are still difficult to predict and they occur on a large scale. The International Maritime Organization (IMO) made it mandatory to install Electronic Chart Display and Information System (ECDIS) for safe seas, but S-57 standards applied to equipment were not updated over 30 years. In addition, it is difficult to keep the equipment up-to-date and revise standards as ships move around the world. In consideration of the limitations of S-57, the IHO developed the new standard as S-100 rather than an update of the S-57. In this study, the previously developed S-100 tool and S/W were configured as one platform and applied to the S-100 ECDIS. The platform conducts as the S-100 cycle and ecosystem from the creation of standards to release and practical use in ships. The hydrographic information standard is machine-readable as defined in S-100, and it has been validated that the latest standard can be applied using the Plug and Play (PnP) function without software system updates. It is expected that international organization such as the International Hydrographic Office (IHO) and the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA) shall develop and release standards and mariners can easily apply the latest standards to equipment through the machine-readable platform.

• 수산경영론집
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• 제51권4호
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• pp.19-45
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• 2020

This study is to evaluate economic effect of the creation project of snow crab, Chionoecetes opilio, spawning and habitat ground in Uljin and Youngdeok county. The main results of this study are summarized as follows: first, 14,400 million won was invested in the creation project cost of Chionoecetes opilio spawning and habitat ground of Uljin and Youngdeok County from 2015 to 2020. Second, the creation project of Chionoecetes opilio spawning and habitat ground directly provides fishing benefits, festival benefits, research and development benefits and employment benefits. Third, on the basis of above benefits, the creation project of Chionoecetes opilio spawning and habitat ground has net present value of 29,900.53 million won, internal rate of return 16.9%, and benefit-cost of 2.91 under a 4.5% social discount rate. Also, the creation project creates 195 jobs. This indicates that the creation project of Chionoecetes opilio spawning and habitat ground not only contributes to the increase in the income of coastal fishery and fishing villages but also to the job making. The result of this study provides useful information to policy makers or project managers as it shows that the project to create spawning and habitat ground should be carried out in consideration of the resource and biological characteristics of individual fish and that economic assessment logic should also be developed based on this. Also, it proves that the project to create a snow crab spawning and habitat ground is a national and local infrastructure project that increases the actual fishing income in the region. At the same time, it maintains the reproducibility function of most fish species, along with enhancing the people's benefits such as fishing village tourism and marine product consumption. Moreover, it provides useful information on budgeting for the continuous development of snow crab spawning and habitat ground in the mid to long-term.

• 한국산학기술학회논문지
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• 제22권5호
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• pp.199-206
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• 2021

본 논문은 잠수함 공격잠망경(Attack periscope) 보호를 위한 보호구조물 설치 타당성 및 신뢰성 검증 방안에 대해 서술하고 있다. 공격잠망경은 잠망경 심도 및 수상 항해 시 대수상 및 대공 표적을 은밀하게 시각적으로 확인하기 위한 핵심 탑재 장비이다. 관측장치 및 거리측정장치를 통해 획득된 표적 정보를 전투체계에 제공하며, 대수상 및 대공탐색하여 자함의 위협 수준 판단과 표적의 영상, 거리를 포함한 위치 정보를 제공한다. OOO급 잠수함 성능개량 시 공격 잠망경을 신규 장비로 교체함에 따라 마스트 길이가 증가하였고, 증가된 마스트 길이만큼 외부로 노출됨에 따라 항해 시 어망, 그물과 같은 해상 부유물에 의한 장비 손상 발생 가능성이 커졌다. 따라서 함교에 공격잠망경 보호구조물을 설치하여 장비 운용성능을 향상시켰으며, CFD 해석 및 실제 해상에서의 수중방사소음 측정을 통해 보호구조물 설치 타당성 및 신뢰성 검증을 수행하였다. 본 연구를 통하여 향후 공격잠망경 신규 장비 교체 시 건전성 확보를 위한 참고자료로 활용될 수 있을 것으로 기대된다.

• 수산해양기술연구
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• 제58권1호
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• pp.10-18
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• 2022

Fishery sea anchor is widely used for many fishing vessels. However, standardization of the dimension and terminology of the fishery sea anchor has not been achieved, reducing the reliability of the performance and safety of the fishery sea anchor. Therefore, this study researches the reality of usage of fishery sea anchor and then attempts to suggest the development direction of the standard draft as basic data. As a result of the survey on the reality of usage show that various terms were used for each part of the fishery sea anchor (including the incorrect form of non-standard words derived from Japanese) and that the production of this product in the fishery sea anchor market was concentrated on one specific manufacturer. In addition, the main specifications of the fishery sea anchor are set and manufactured based on conventional experience without standards. In the field, there was no standardized drawing for fishery sea anchor and users had low awareness of the main specifications of fishery sea anchor. Therefore, this study suggested the following regarding the fishery sea anchor: standard terms for each part including Korean and English names and standard drawing of sea anchor. It is hoped that this study will contribute to research for the standardization of fishery sea anchor, which will increase in reliability and lead to increased interest in standardization in the fishery field.

• 한국축산식품학회지
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• 제43권3호
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• pp.383-401
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• 2023

Camel milk has a significant and pivotal role in the diet of people residing in semi-arid and arid regions. Ever since ancient times, marketing of camel milk has remained insignificant due to nonexistence of processing amenities in the camel nurturing areas, hence the utilization of unprocessed camel milk has continuously remained limited at family level by the nomads. Due to the superior medicinal values and health promoting effects, incredible growth in the demand of camel milk and dairy products have been noticed all over the world during last two decades. Such emergence has led dairy industry to provide diversified camel dairy products to the consumers with superior nutritional and functional qualities. In contrast to bovine, very few food products derived from camel milk are available in the present market. With the advancements in food processing interventions, a wide range of dairy and non-dairy products could be obtained from camel milk, including milk powder, cheese, yogurt, ice cream, and even chocolate. In some regions, camel milk is used for traditional dishes such as fermented milk, camel milk tea, or as a base for soups and stews. Current review highlights the processing opportunities regarding the transformation of camel milk into various dairy products via decreasing the inherent functionality that could be achieved by optimization of processing conditions and alteration of chemical composition by using fortification method. Additionally, future research directions could be devised to improve the product quality.

• Journal of Platform Technology
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• 제11권4호
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• pp.62-70
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• 2023

이 논문은 농수산물 생산자가 도매시장에 상품을 출하하는 시기와 양을 결정하는 것을 돕기 위한 시스템을 구축하기 위한 일련의 과정 중 일부이다. 기존 농수산물 출하모델에서 사용하지 않은 품질변화효과를 모델링하고, 그 통계적 유의성을 확인한 후, 시스템에 도입하는 것이 이 연구의 목적이다. 이를 위해 연구자는 품질변화효과를 측정할 수 있는 네 가지 모델을 개발하였다. 시간이 지남에 따라 1) 품질이 일정하게 떨어지는 경우, 2) 품질이 처음에 급속히 떨어지다가 나중에는 천천히 떨어지는 경우, 3) 품질이 처음에 천천히 떨어지다가 나중에는 급속히 떨어지는 경우, 4) 품질이 낮았다가 시간이 흐른 후 높아지다가 다시 감소하는 경우를 모델링하였다. 각 모델의 품질변화효과가 출하량에 미지는 영향을 2014-2021년 사이에 가락도매시장에서 거래된 사과를 대상으로 실증분석 해 본 결과에 따르면 네 모델 모두 품질변화효과에 유의성을 발견하였다. 그리고 네 모델 간 설명력에 유의한 차이는 없었다. 따라서 네 개 모델 중 어느 하나를 선택해서 사과에 대한 출하시기의사결정시스템에 적용시킬 수 있는 것으로 나타났다.

• 한국융합학회논문지
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• 제13권1호
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• pp.215-228
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• 2022

본 연구는 잡지광고의 착시 디자인 기법을 총괄하고 분석함으로써 착시 잡지광고와 그렇지 않은 일반 잡지광고 디자인을 비교하고, 잡지광고를 통해 시각 착시 형 디자인 언어의 응용 전망과 디자인 강점을 정리함으로써 향후 평면 디자인 분야에 기여하는 것을 목적으로 한다. 먼저 선행 연구의 문헌 분석과 사례연구를 통해 착시 디자인의 특성과 효과를 고찰했다. 다음으로 착시 디자인의 잡지광고 효과를 분석하기 위해 착시 잡지광고와 일반 잡지광고를 비교하는 설문조사를 실시했으며 IBM SPSS 27.0 프로그램을 이용한 통계 분석, 신뢰성, 탐색적 요인 분석을 통해 착시 디자인의 영향을 검토했다. 향후 착시 디자인 적용 시에는 무엇보다 시각적 충격과 제품의 함의를 효과적으로 조합하여 표현하는 것에 중점을 두어야 한다. 착시의 중의성, 모순, 재미, 모호함 등의 특성을 십분 활용하면서도 착시 현상의 시각 언어와 조합 구조를 적절히 활용할 때 브랜드가 전달하는 특징을 극대화하여 홍보할 수 있다.

• 한국식생활문화학회지
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• 제22권4호
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• pp.511-519
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• 2007

The purpose of this study was to evaluate satisfaction degree on menu served and identify food preference of the meal served to 271 business and industry foodservice workers from 4 institutions by gender difference. The demographics indicated that male(54.6%) and female(45.4%) were about an half each, mean age was ranged from 20 to 39 years old. The workers were not contented with most of menu quality attributes served from past foodservice operation. Primary complaint was improper temperature of the meal. Most workers liked meat and fish(52.1%) the most. Sensory quality evaluation from all workers was 3.37 points out of 5 points. However, female workers rated higher on the most of menu(3.72 points) compared with that of male workers(3.35 points), indicating that satisfaction was higher in the female workers(p<0.05). Mean preference of all the menu according to food type also have shown higher in female(3.52 point) than in male(3.45 point). Best food preference according to food type considering cooking method of male was given to barley rice, boiled rice with assorted mixtures, marine product stew, and Kimchi stew. On the other hand, females cared for curried rice, hash rice, and spaghetti but males have shown low preferences to those foods females liked. Also, females liked more of fried, grilled and broiled food. However, both males and females showed indifferent taste about the food cooked with steamed and stewed. From the findings, the business and industry foodservice workers were not well satisfied with menu quality considerably and differed in food preferences by gender clearly. Therefore, the manager of foodservice institution require to consider composition of gender ratio in menu preparation along with sensory quality evaluation to lead the successful foodservice management.

• 한국포장학회지
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• 제30권1호
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• pp.23-30
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• 2024

곤드레의 이용과 김치의 다양성을 모색하기 위해 강원도의 특산물인 곤드레를 김치제조에 이용하고자 하였다. 곤드레는 당과 단백질이 풍부한 식품으로 김치제조에 생 또는 삶은 형태로 이용을 검토한 결과 일반 성분은 비슷하였지만 항산화성이 생 곤드레가 삶은 곤드레보다 1.2배 많은 것으로 나타나 김치제조에 생 곤드레를 첨가하기로 하였다. 생곤드레를 배추김치에 20, 40 및 50 (w/w) 첨가하여 저장실험한 결과 pH, 산도 및 미생물의 변화는 곤드레의 첨가량과 관계없이 유사한 경향을 보였고 관능검사를 한 결과 곤드레를 20% (w/w) 첨가한 김치가 맛, 향, 색 및 전체적인 기호도에서 우수한 것으로 나타나 향후 김치 제조에 곤드레의 이용이 가능할 것으로 사료되었다.