• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.3
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• pp.448-453
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• 2015

This study was performed to estimate biomass and to provide management plan through population ecological characteristics, including survival rate, instantaneous coefficient of natural and fishing mortalities, and age at first capture of Flathead grey mullet, Mugil cephalus, in the coastal waters of Yeosu. Survival rate (S) of the flathead grey mullet was 3.671. The instantaneous coefficients of natural mortality (M) and fishing mortality (F) was estimated to be 0.325/year, 0.962/year for flathead grey mullet. Also fist capure age of flathead grey mullet was 3.61year. The current biomass of the flathead grey mullet in the study area was estimated to be 19.6 M/T and $F_{0.1}$ and $F_{40%}$ were estimated 0.340/year, 0.225/year. For the stock assessment result, flathead grey mullet was not overfished but overfishing.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.1
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• pp.9-18
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• 2020

We investigated the maturity and spawning dynamics of chub mackerel Scomber japonicus in Korean waters using samples collected by a large purse seine fishery from January 2013 to December 2017. We analyzed sex ratio, monthly maturity stage, gonadosomatic index (GSI), Fulton's condition factor (K), and fork length at 50% group maturity. Spawning occurred from March to June, with a peak in May. We detected a significant difference in sex ratio (χ² test, P<0.05). The relationship between fork length and body weight was expressed as BW=0.0025FL^3.4693. We estimated 50% group maturity at a female fork length of 29.3 cm.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.2
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• pp.129-140
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• 2008

This study was performed to estimate biomass and to provide management plan through population ecological characteristics, including growth parameters, survival rate, instantaneous coefficient of natural and fishing mortalities, and age at first capture of hen clam, Mactra chinensis, in the Dong-li self-regulatory community of Busan. The von Bertalanffy growth parameters estimated from a non-linear regression were $SH_{\infty}=86.24mm$, K=0.12/year, and = -1.37year. Survival rate(s) of the hen clam was 0.515. The instantaneous coefficients of natural mortality(M) was estimated to be 0.232/year and fishing mortality(F) 0.432/year for hen clam. The current biomass of the hen clam in the study area was estimated to be 713mt and the acceptable biological catch(ABC) was estimated under various harvest strategies based on $F_{0.1}$ and $F_{40%}$.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.7
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• pp.723-729
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• 2012

Spring-like leg models have been employed to explain various dynamic characteristics in human walking. However, this leg stiffness model has limitations to represent complex motion of actual human gait, especially the behaviors of each lower limb joint. The purpose of this research was to determine changes of total leg stiffness and lower limb joint stiffness with gait speed in knee osteoarthritis. Joint stiffness defined as the ratio of the joint torque change to the angular displacement change. Eight subjects with knee osteoarthritis participated to this study. The subject walked on a 12 m long and 1 m wide walkway with three sets of four different randomly ordered gait speeds, ranging from their self-selected speed to maximum speed. Kinetic and kinematic data were measured using three force plates and an optical marker system, respectively. Joint torques of lower limb joints calculated by a multi-segment inverse dynamics model. Total leg and each lower limb joint had constant stiffness during single support phase. The leg and hip joint stiffness increased with gait speed. The correlation between knee joint angles and torques had significant changed by the degree of severity of knee osteoarthritis.

• Journal of Agricultural Extension & Community Development
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• v.29 no.3
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• pp.155-172
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• 2022

Ecotourism as a alternative tourism destination has to adapt to current market mechanisms, which is becoming extremely competitive and which are dominated by communication and promotion strategies and techniques. We need to know the causative factors and influences by which tourists are motivated to become included in various market segments. The primary purpose of this study is to segment and profile the motivations of ecotourist, so as to enable a better understanding of ecotourism in Korea. A self-administered survey was collected from 200 tourists in the study area. A factor-clustering method identified four distinct segments: want-it-all seeker, passive seeker, aesthetic seeker, value sharing seeker. We conclude by considering the relevant of our findings to ongoing discussions of ecotourists' market segmentation.

• Journal of agricultural medicine and community health
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• v.46 no.2
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• pp.53-66
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• 2021

목적: 농촌 지역사회 기반의 허리 근력 강화 운동 프로그램이 운동과 허리 건강에 대한 개인의 태도 및 믿음에 미치는 효과를 평가하고자 하였다. 방법: 강원도 지역 네 개의 농촌 마을에서 가벼운 허리 통증이 있는 79명의 여성 자원자(42-76세)들을 운동군(n=40)과 대조군(n=39)으로 마을단위로 배정하였다. 운동군에서는 지역사회 기반의 허리강화 운동 프로그램(주당 3회, 8주간)이 시행되었고 대조군에는 일반적인 건강 관리에 대한 강의가 제공되었다. 등척성 허리 신전 근력과 허리 통증 관련 장애, 운동에 대한 태도, 허리 질환에 대한 위협인지, 운동의 자기 효능감을 중재전과 중재후 1, 2개월째 측정하였다. 결과: 운동군에서 2개월후 허리 신전근력은 뚜렷이 증가하였으며 허리 통증 관련 장애도 유의미하게 감소하였다. 운동에 대한 태도와 허리 질환에 대한 위협 인지는 운동군에서 증가하였으나 대조군에서는 변화가 없었다. 운동의 자기효능감은 양군에서 같이 증가하였으나 운동군에서 그 정도가 더 뚜렷했다. 결론: 농촌 지역 여성들을 대상으로 한 허리 근력 강화 운동 프로그램은 허리 통증으로 인한 장애를 감소시켰고 운동의 효과에 대한 태도와 믿음을 변화시켰다.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.8
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• pp.431-439
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• 2002

Due to the recent development of graphics hardware, real-time rendering of complex scenes is still a challenging task. As results of researches on image based rendering, the rendering schemes based on post-rendering 3D warping have been proposed. In general, these methods produce good rendering results. However, they are not appropriate for real-time rendering since it is not easy to accelerate the time-consuming algorithms within graphics subsystem. As an attempt to resolve this problem of the post-rendering 3D warping technique, we present a new real-time scheme based on projective texture. In our method, two reference images obtained by rendering complicated objects at two consecutive points of time are used. Rendering images of high quality for intermediate points of time are obtained by projecting the reference images onto a simplified object, and then blending the resulting images. Our technique will be effectively used in developing real-time graphics applications such as 3D games and virtual reality software and so on.

• Composites Research
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• v.15 no.2
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• pp.32-39
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• 2002

This study focused on the introduction of processing procedure for microcapsules loaded with the healing agent and then microcapsules with the healing agent were manufactured by experiments. The DCPD (dicyclopentadiene) was used for the healing agent and the shell of microcapsules was consisted of urea-formaldehyde resin. The magnitude and the site distribution of microcapsules were measured by a particle size analyzer using laser diffraction technique. Thermal analysis was conducted by using a DSC fur the healing agent, microcapsules without the healing agent, and microcapsules with the healing agent. Also thermal stability was investigated by using a TGA under continuous and isothermal heating conditions far the healing agent, microcapsules without the healing agent, microcapsules with the healing agent. According to the results. microcapsules with the healing agent were verified to be so thermally stable that the healing agent could not evaporate until the shell of microcapsules were burned.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.1
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• pp.32-49
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• 2010

Ecosystem-based fisheries management requires a holistic assessment of the status of fisheries by integrating fishery ecosystem indicators for management objectives. In this study four objectives were identified such as the maintenance of the sustainability, biodiversity and habitat quality and socio-economic benefits. The ecosystem-based fisheries assessment (EBFA) model to assess fisheries and their resources at the ecosystem level developed for Korean fisheries (Zhang et al., 2009) has a number of indicators for three management objectives. However, it was found that there were some overlapping components among indicators and that there were difficulties in assessing some indicators in the EBFA model. This study identified problems of the approach and suggested more pragmatic and simpler indicators. It also presented alternative reference points to assess indicators and discussed issues associated with the application of the EBFA model to a marine ranching ecosystem. In this study a total of 24 indicators were used for the assessment which included 4 socio-economic indicators. New indicators and reference points were demonstrated by applying it to the Uljin marine ranch.

• Korean Journal of Environmental Agriculture
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• v.28 no.4
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• pp.427-434
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• 2009

Analytical method for prochloraz in cabbage, apple, pepper, mandarin, and hulled rice was established by conversion it to 2,4,6-trichlorophenol (TCP). Crop samples were extracted with acetonitrile, and partitioned with dichloromethane. The sample extracts were hydrolyzed with pyridine hydrochloride in a vial by heating for 1 hour, and analyzed with GC-ECD after partitioning with dichloromethane. Method quantification limit (MQL) of prochloraz was 0.01 mg/kg. Recoveries at 0.1 mg/kg level was 105-113% while at 0.5 mg/kg level was 82-87%. In both of the cases CV was less than 10%. Through this procedure soxhlet extraction and refluxing apparatus of conventional method were discarded and simple solvent extraction and small vial were successfully employed, resulting in simple, rapid, economic and more precise method.