• Journal of the Korean Geotechnical Society
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• v.33 no.6
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• pp.27-36
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• 2017

Gravel compaction pile method has been widely used to improve the soft ground on the land or sea as one of the soft ground improvement technique. The ultimate bearing capacity of the ground reinforced by gravel compaction piles is affected by the soil strength, the replacement ratio of pile, construction conditions, and so on, and various prediction equations have been proposed to predict this. However, the prediction of the ultimate bearing capacity using the existing models has a very large error and variation, and it is not suitable for practical design. In this study, multiple regression analysis was performed using field loading test results to predict the ultimate bearing capacity of ground reinforced by gravel compaction pile, and the most efficient input variables are selected through evaluation of error by leave one out cross validation, and a multiple regression equation for the prediction of ultimate bearing capacity was proposed. In addition, the prediction error was evaluated by applying artificial neural network using the selected input variables, and the results were compared with those of the existing model.

• The Journal of Fisheries Business Administration
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• v.29 no.1
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• pp.139-159
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• 1998

본 연구는 미국 오레곤주의 수산업 특성을 개괄적으로 살펴본 것이다. 먼저, 오레곤의 상업적 수산업을 역사적으로 살펴보면 2가지 주요한 계기가 있음을 알 수 있다. 첫째는 자급자족 차원에서의 연어생산을 수출품으로 변화시킨 연어통조림 생산기술의 발전이고, 둘째는 현대식 트롤어업이 도입된 점이다. 오레곤에서 주로 사용되는 어구ㆍ어법은 트롤, 채낚기, 연승, 통발, 형망 등이며, 생산어종은 연어, 게, 새우, 참치, 대구 등이다. 1995년 오레곤은 약 2억 4천 파운드의 수산물을 생산하여 미국 연안주중에서 6위를 차지하고 있고, 생산금액에서는 12위를 기록하였다. 한편, 양식업은 아직 성행하지 않아 그 생산품종 및 생산량은 미미한 실정이다. 그 주된 이유 중의 하나는 양식시설을 하기 위해서는 여러 관계기관의 허가를 필요로 하는 등 행정상의 절차가 복잡하기 때문이다. 오레곤의 수산자원관리는 우리나라에 비해 암계의 어획금지, 통발 등 정치어구ㆍ어법에 대한 인망일수의 제한, 조개류의 판매가능시간의 제한 등 몇가지 특징을 들 수 있다. 오레곤의 수산업관리제도(연안으로부터 3마일 이내)를 살펴보면, 아직 TAG제도를 도입하지 않고 있으며 생산요소역입제한방식이 채택되고 있다. 즉, 상업적으로 허용된 어종을 어획하려는 어업자는 등록절차를 필히 거쳐야 어업행위를 할 수 있으며, 등록수를 제한할 필요가 있는 특정한 어업(연어, 새우, 가리비 등)에 대해서는 행정관청으로부터 허가를 얻고 어업행위를 해야 한다. 즉, 허가어업은 등록어업보다 더욱 제한적인 어업행위를 말하며, 허가권에 대해서는 자유로운 매매양도가 허용되어 있다. 수산물의 마케팅시스템에 대해서는 우리나라에 지배적인 형태인 경매제도가 도입되어 있지 않다. 즉, 모든 수산물은 개인적인 거래계약에 의해서 유통된다. 다만 마케팅경로에 참여하고 있는 모든 구성원은 일정한 등록절차를 마쳐야 하며, 주내에서 거래되는 수산물의 일관된 통제나 관리를 위해 관계기관에 거래량을 필히 신고해야 한다. 우리나라의 중도매인은 주로 생산지의 수협(또는 내륙지 도매법인)과 도매상의 사이에 존재하나 오레곤의 중도매인은 마케팅경로 어디에든 존재하고 있다.

• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.309-316
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• 2009

The usefulness of media representations for assessing normative standards depends in part on how accurately media reflect "on-the-ground" resource conditions. This study compared encounter standards based on still and moving pictures to assess movement effects. The study location was the Jungmoeri area of Mudeungsan Provincial Park (MPP) in Korea. A total of 50 college students participated in a laboratory experiment where they evaluated still and moving pictures constructed using Photoshop and Flash computer programs. For the maximum acceptable number (MAN), however, there was no significant difference of ratings between still and moving pictures, and the overall encounter norm curves were nearly identical. There were some "method findings" for ordering effects and percent of people moving, but for a resource manager developing standards there was no advantage to the more complex logistics of using moving pictures to assess this particular impact. The trade-offs of using more sophisticated media are discussed, and more research is needed to further explore factors such as movement of sound in evaluation of other resource conditions.

• Journal of The Korean Association For Science Education
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• v.30 no.1
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• pp.68-79
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• 2010

This study utilized the What Is Happening In this Class (WIHIC) questionnaire to examine students' perceptions of their science learning environment. Data was collected from 587 middle school students in seven coeducation schools in Seoul. Higher mean scores occurred on the scales of Student cohesiveness, Task orientation, Cooperation and Equity in the WIHIC, whereas lower mean scores occurred on Teacher support, Involvement and Investigation. The effects of gender on students' perceptions of their science learning environment were not statistically significant overall, but girls perceived Student cohesiveness and Cooperation more positively than boys. Correlations between the WIHIC scales of the low-level group that perceived their learning environments negatively (10 percentiles) and the high-level group that perceived their learning environments positively (90 percentiles) were computed. Teacher support, Involvement, Task Orientation and Investigation were highly correlated with each other in the low-level group, whereas only Teacher support and Equity were correlated in the high group. Educational implications were discussed.

• Child Health Nursing Research
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• v.12 no.3
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• pp.405-416
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• 2006

Purpose: The purpose of this study was to explore health behavior and perception of therapeutic restrictions in chronically ill children and their parents in Korea. Method: Nine children with chronic disease and of six of their parents were interviewed using semi-structured a questionnaire. The data were analyzed using explorative content analysis. Results: Health behaviors related to therapeutic restrictions was classified into four domains, and the perceptions of therapeutic restrictions into two domains. The domains regarding compliance in health behavior with therapeutic restrictions included control-centered restrictions (maintaining food limitations, avoiding harmful environments, restriction on physical activity, restriction on social activity, restriction on learning activity), and everyday pursuit of balance(preference for healthy diet, maintaining a regular life style, maintaining a standard body weight, pursuing psychological well-being, family participation). Domains regarding perception of therapeutic restrictions included obstacles to growth and development (bridled life, opportunity deprivation, prevented from playing proper role), origin of conflict (tenacity, conflict, stressor, cover-up), task for normal life (doing proper duty), and everyday affairs (becoming ordinary, familiarity). Conclusion: This study will help to enhance understanding the behavior and perception of therapeutic restrictions by chronically ill children and their families and to establish educational programs and counseling for these children and their families.

• Mycobiology
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• v.35 no.2
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• pp.54-61
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• 2007

Two isolates of Tricholoma matsutake T-008 and T-034, preserved in Entomopathogenic Fungal Culture Collection (EFCC) of Korea, were used in the present study. The isolates had 100% Bootstrap homology with Tricholoma matsutake U62964 and T. matsutake AB188557 and AF309538 preserved in Gene Bank of NCBI. Mycelial growth of T. matsutake was highest in TMM and MYA at $25^{\circ}C$. The highest dry wt. of mycelium was obtained after 65 days of culture, when 6 mycelial discs were inoculated in 100 ml of broth in 250 ml shaking flask. Mycelial mats were observed in clumped condition at the inoculation sites of pine forest after two weeks of inoculation. After 5 months of inoculation, mycelia mats were observed growing inside soil and walls of a few inoculation sites, while mycelial mats growth up to $5{\sim}8$ cm were observed in the roots of pine tree after 6 months. The survival rate of the inoculum was about 40% of the total inoculation sites. The survival rate was found below 20% when the mycelium was inoculated in the summer. The reasons for low survival rates of the mycelium were mainly due to dry season and the soil-borne small animals such as earthworm and mole. After one year of inoculation, no external difference was observed between the artificially inoculated mycelia and the naturally existing mycelia of T. matsutake. The present study showed that fruiting bodies of T. matsutake could be produced by artificial inoculation under the appropriate environmental conditions.

• Preventive Nutrition and Food Science
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• v.10 no.4
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• pp.364-371
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• 2005

This study was performed to evaluate effects of dietary variety scores (DVS) and dietary diversity scores (DDS) on the nutritional quality of the diets of Korean college students, and to examine the association between food group intake patterns and nutritional adequacy. This study examined the relationship of dietary diversity scores (DDS), dietary variety scores (DVS), and food group intake patterns with nutrient intakes using 24-hour recall data (n=.358). The .DDS was calculated from the sum of each of the five food groups consumed as a score of 'I'. DVS was determined by counting the number of food items consumed daily. Food group intake patterns were expressed with the presence or omission of five major food groups-dairy, meat, grain, fruit, and vegetable. The four most prevalent food group patterns and the proportion of the population reporting them were as follows; no dairy and fruit, $23\%;\;no\;dairy,\;20\%;$ no dairy, meat, and fruit, $15\%$; all food groups, $14\%$. Even though the DDS or DVS was higher, the majority of this study population failed to meet the Korean RDA for calcium in both genders and iron in women. Higher DVS scores $(\geq31)$, within all DDS groups, were associated with the largest proportion of individuals consuming more than $75\%$ of the Korean RDA for selected nutrients. The consistency of these results indicates that screening diets to evaluate the overall dietary variety and variety among the major food groups including food group intake patterns provide meaningful information about their quality.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.4
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• pp.643-650
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• 2020

The phased array antenna has an advantage enabling rapid beam aim without the mechanical rotation of the antenna, because it arranges multiple elements in a linear or planer (grid or circular) and electronically controls the phase for each element. The planar array antenna is generally used a grid array and a circular array, and the circular form has the higher resolution comparing to the grid form due to the its structural characteristics. However, a concentric circular array (CCA) or a concentric ring array (CRA) with multiple circular arrays which each has different radius is used in the limited area, because the entire radius should be increased for the circular array with a number of elements. In this paper, we introduce the angle-of-arrival (AOA) estimator for an adaptive beamforming satellite system based on CRA and provide the simulation results for performance evaluation. In addition, simulation results are compared and analyzed to the case for the circular array antenna.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.1
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• pp.25-38
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• 1993

Numerical models of directional wave spectra for the analysis of offshore structural cable responses are verified. Alternative spreading models are used to predict wave-induced flows in water and for mooring systems. Hydrodynamic wave forces upon cable are estimated. using a Morison formula encompassing considerations for drag and for inertial forces both parallel and tangential to the slope of the cable. Numerical analysis for directional random waves. including consideration of displacement and velocity, trajectory, phase plane response. and tension are shown for mooring system cable responses at both the tether point for a buoy and at the anchor point. The effects of wave forces far different drag coefficients, various significant wave heights, and selected wave parameters are considered in the analysis. For the specific systems considered in the examples, it is demonstrated that wave period and height as well as wave spreading function parameters and drag coefficients, have an important effect upon the dynamic responses of the cable-buoy systems.

• Journal of the Korean Geotechnical Society
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• v.33 no.5
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• pp.25-35
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• 2017

Liquefaction is one of the major seismic damage, and several methods have been developed to evaluate the possibility of liquefaction. Recently, a probabilistic approach has been studied to overcome the drawback of deterministic approaches, and to consider the uncertainties of soil properties. In this study, the spatial variability of cone penetration resistance was evaluated using CPT data from three locations having different variability characteristics to perform the probabilistic analysis considering the spatial variability of soil properties. Then the random fields of cone penetration resistance considering the spatial variability of each point were generated, and a probabilistic analysis of liquefaction induced settlement was carried out through CPT-based liquefaction evaluation method. As a result, the uncertainty of soil properties can be overestimated when the spatial variability is not considered, and significant probabilistic differences can occur up to about 30% depending on the allowable settlement.