• Title/Summary/Keyword: Fishing types

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Catch Specification of Japanese Tuna Purse Seine in the Western Pacific Ocean (서부태평야지역에서 일본 다랑어선망어업의 어획특성)

  • 김형석
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.35 no.3
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    • pp.243-249
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    • 1999
  • Specificity of catches has been analyzed to japanese tuna purse seine A principle component analysis was used to improve the efficiency of fishing and increase sustainable production and productivity of Korean tuna purse seine.The result are as follows;From the principal component analysis of the fish catches, the first principal component(Z1) to promote principal component score was skipjack Kastsuwonus Pelamis, LINNAEUS and yellowfin tuna Thunnus Albacares, BONNATERRE (Small : smaller than 10kg) and proportion was 86.8% of total. The second principal component(Z2) to increase principal component score was yellowfin tuna (Large : larger than 10kg) and proportion was 9.5%.On the other hand, fish operating that have caught skipjack and yellowfin tuna (Small and Larger) was not so much. Fish catches for one species raised volume of the catches while catches for multi-species decreased it since principal composition score for one species and both species together has been increased.Fish school could be divided into three groups of schools each of which was associated with drift objects, payaho and ship, school associated with shark, whale and porpoise and school of breezing, feeding and jumping from proportion of principal component analysis for fish catches of school types. However, the biological pattern is different among school associated with ship, payaho and school associated with drift objects for analysis eigen vector. School associated with ship, payaho and school associated with drifting object associated is judged as school which be assembled to vessel and drifted log temporary.

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An Analysis of Fishermen's Perception to Climate Change in Korea (기후변화에 대한 어업인 인식의 특성 분석)

  • Kim, Bong-Tae;Lee, Sang-Geon;Jeong, Myung-Saeng
    • The Journal of Fisheries Business Administration
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    • v.45 no.3
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    • pp.71-84
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    • 2014
  • This study indicates that 84.5% of fishermen have perceived climate change and 74.9% of fishermen have responded that frequency and intensity of the impacts of climate change are increasing. The results of regression analysis have shown that the level of fishermen experiencing the impacts of climate change differs according to individual's characteristics including age, length of experience, sea area (fishing area) and types of fisheries. About half of the respondents have shown that they are not taking any actions against the effects of climate change. The main reasons are that they either have lack of knowledge on how to respond to the impacts of climate change or have the perception that climate change is irresistible. The majority of respondents have responded that they are not aware of the government's climate change policy and emphasized that it is necessary to have effective countermeasures strengthening the provision of information about climate change policy. The result of perception survey have highlighted that it is essential for the government and the fishermen to share relevant information and to consider method of cooperation.

A Study on Diesel Engine NOx and Soot Emission Characteristics using Different Fuel Oils

  • Nam, Jeong-Gil;Kang, Dae-Sun
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.7
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    • pp.1080-1088
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    • 2008
  • This paper addresses some concerns faced by the shipping industry nowadays. Initially, the environmental issues were resolved and stricter regulations are now being implemented with regards to the exhaust gas, specifically nitrogen oxides (NOx) and sulfur oxides (SOx), emitted from ships. Secondly, with the increasing and unstable cost of fuel oils in the world market, it has become almost a necessity to explore on a new alternative fuel. Hence, this study was conducted. An experiment was carried-out on a fishing survey vessel with the main engine (M/E) and generator engine (G/E) operated on expensive marine gas oil (MGO). During the experiment, two pre-refinery systems were installed and different fuel oil samples were employed for the M/E and the G/E. Furthermore, the NOx emission and soot concentration were monitored and verified. The results confirmed the compatibility of some fuel oil types to the engines and meeting the emission standards. MDO, MF15 and Bunker A can be used in place of MGO for the engines(M/E, G/E).

A Study on the Location Characteristics of Rural Village along a Dalchon River in Geosan of Chungbuk Province (충북 괴산군 달천 유역 농촌마을의 입지특성에 관한 연구)

  • Roh, Seon-Hwa;Kim, Sung-Jung;Kim, Tai-Young
    • Journal of the Korean Institute of Rural Architecture
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    • v.7 no.1
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    • pp.19-30
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    • 2005
  • This study is carried out to understand the characteristic of location in vernacular agricultural villages by judging from natural environment around the village. For this purpose, there were selected 17 villages of the riverside villages in Geosan Area which lean against Dalchoen River. After classifying these samples by the morphorogical approach, according to compare them with pre-researched villages, the methodology of spatial structure was investigated in agricultural villages. As a result of the study, the relationship between the agricultural villages and the shape of Dalcheon River can be classified by 3 types that are twisted around villages, attacked villages, and paralleled with villages. First of all, twisted type is located in river terraces, river safety zone and taken a image of the riverside agricultural village. Secondary, attacked type is located in beside riffle, and taken a image of a fishing village. Finally, paralleled type is located in straightly flowing river.

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A Study on Prediction of Propulsive Energy Loss Related to Automatic Steering of Ships in Following Seas (추사피중에서 자동조타로써 항행하는 선박의 추진에너지 손실량 평가에 관한 연구)

  • 이경우;손경호
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 1996.04a
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    • pp.77-92
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    • 1996
  • When an automatic course-keeping is concerned as is quite popular in modern navigation the closed-loop steering system consists of autopilot device power unit (or telemotor unit) steering gear magnetic or gyro compass and ship dynamics. The consideration of irregular disturbances to ship dyanmics and a few non-linear mechanisms involved in the system inevitably or artificially are known to be very important in properly evaluating or analyzing the automatic steering system. In the present study the mathematical model of each element of an automatic steering system is derived which takes account of a fex non-linear mechanisms. PD(Proportional-Derivative) controller and low-pass filter with a weather adjustment are adopted to modelling the characteristics of an autopilot. The calculation method of imposing irregular disturbances to ship dynamics is proposed where irregular disturbances implying irregular wave and the fluctuating component of wind. For he evaluation of automatic steering system of ships in the open seas an important term "performance index" is introduced from the viewpoint of energy saving which derived from the concept of energy loss on ship propulsion. Finally the present methods are applied to two typical types of ship ; an ore carrier and a fishing boat. The various effects of linear and/or non-linear control constants of autopilot on propulsive energy loss are investigated to validate and clarify the present smulation technique.

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Strength Characteristics of FRP Composite Materials for Ship Structure (선체구조용 FRP 복합재료의 강도 특성)

  • Choi, Han-Kyu;Nam, Ki-Woo;Ahn, Seok-Hwan
    • Journal of Ocean Engineering and Technology
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    • v.27 no.4
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    • pp.45-54
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    • 2013
  • In this study, various types of composite materials and adhesives that are actually used in the shipbuilding field for small ships, leisure boats, and fishing boats were applied in the hand lay-up method and vacuum infusion method to manufacture specimens. Then the tensile strength, tensile modulus, flexural strength, and flexural modulus values of these specimens were obtained. In addition, the barcol hardness and fiber content were obtained from the specimens. The results showed that the strengths of the specimens manufactured using the vacuum infusion method were higher than those manufactured using the hand lay-up method. Moreover, the barcol hardness and fiber content were also higher in those manufactured using the vacuum infusion method. The specimens manufactured using the vacuum infusion method were thinner despite their large fiber content.

A Study on Applications of Housing Interior Design Elements according to the Sensibility Type (감성유형에 따른 주거 실내디자인요소 적용방안)

  • Park, Ji-Min;Park, En-Sun
    • Journal of the Korean housing association
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    • v.25 no.3
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    • pp.165-179
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    • 2014
  • The purpose of this study was to draw application elements of housing interior design according to user-oriented sensibility types. The sensibility evaluation experiments were conducted to target the general user 118 people using the sensibility evaluation tool for housing interior space. The results of the analysis were as: To produce the 'cozy' space, the colors and materials giving soft and natural feeling should be used. For the 'practical' space, type of ceiling and window that give the visually open feeling, the user-oriented furniture arrangement that allows using the space efficiently. For the 'cheerful' space, the simple and natural effects should be produced by using closed space that stable. For the 'traditional' space, the natural fishing material having rough texture should be used. For the 'unique' space, the space contained the dynamic feeling by the diagonal or vertical line and the graphic expression in the wall. For the 'congenial' emotional space, basic is the symmetric, stable and simple space. On the other hand, for the material, small size, natural texture or typical and soft materials should be used. For the 'sensuous' space, the dynamic and vertical sense of space should be expressed by the type of ceiling. The most important elements for the space of 'gorgeous' sensibility, is the color.

The Effect of Public Service on the Quality of Life and Policy Properties - Focused on the Evaluation of Quality of Life for the Elderly in Rural Area - (공공서비스가 삶의 질에 미치는 효과와 정책속성 - 농촌노인들의 삶의 질 평가를 중심으로 -)

  • Lee, Seo-Gu;Shin, Dong-Ho;Kim, Jung-Tae
    • Journal of Korean Society of Rural Planning
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    • v.26 no.4
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    • pp.93-105
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    • 2020
  • This study is an experimental study that examines the policy attributes that local governments should choose to manage the quality of life of rural residents. The analysis data used raw materials for the survey of the welfare status of farmers and fishermen surveyed by the Rural Development Administration. The analysis method used Quantile Regression. The policy attributes of public services were interpreted on the basis of Peterson (1981)'s theory of policy types and the discussion of Holland (2015). According to the analysis results, the higher the quality of life, the greater the importance of the relationship between the safety sector and the neighbors. The effective policy attributes for improving quality of life in rural areas are the policies of local governments where policy benefits can directly go to individuals, or lead to social improvement. It shows that the higher the level of safety and the quality of life of our neighbors, the greater its importance.

Moored Current Observation: Shallow-Water Mooring (해류계 계류에 의한 해류관측: 천해계류)

  • 황상철;장경일;석문식;장영석
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.4
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    • pp.286-303
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    • 2002
  • Korea Ocean Research and Development Institute (KORDI) has attempted moored current measurements since 1978. This note describes mooring types and failures of moorings deployed in coastal and continental shelf regions around Korea. Taut-wire U-type mooring lines and trawl-resistant bottom mounts have been mainly used in shallow seas. In order to avoid the failure of moorings in the shallow seas, it is needed to (1) design a proper mooring plan considering local mooring environments including fishing activities and (2) use adequate mooring equipments and parts considering mooring period, depth, and other factors that could affect the mooring unexpectedly.

A study on exhaust emission characteristics according to operating conditions and butanol blended fuels in a small diesel engine for fishing vessel (소형 어선용 디젤기관의 운전조건과 부탄올 혼합유의 배기 배출물 특성에 관한 연구)

  • KIM, Sang-Am;WANG, Woo-Gyeong
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.57 no.3
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    • pp.256-263
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    • 2021
  • In this study, blending oils of diesel oil and butanol were used as fuel oil for diesel engine to measure combustion pressure, fuel consumption, air ratio and exhaust gas emission due to various operating conditions such as engine revolution and torque. Using these data, the results of analyzing the engine performance, combustion characteristics and exhaust emission characteristics such as NOx (nitrogen oxides), CO2 (carbon dioxide), CO (carbon monoxide) and soot were as follows. The fuel conversion efficiency at each load was highest when driven in the engine revolution determined by a fixed pitch propeller law. Except 30% butanol blending oil, fuel conversion efficiency of the other fuel oils increased as the load increased. Compared to diesel oil, using 10% and 20% butanol blending oil as fuel oil was advantageous in terms of thermal efficiency, but it did not have a significant impact on the reduction of exhaust gas emissions. On the other hand, future research is needed on the results of the 20% butanol blending oil showing lower or similar levels of smoke concentration and carbon monoxide emission rate other than those types of diesel oil.