• Korean Journal of Soil Science and Fertilizer
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• v.24 no.4
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• pp.248-253
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• 1991

This study examines the effect of submergence on transformations of inorganic phosphorus and the relation between fractions of inorganic phosphorus and adsorbed phosphorus in Gangseo (paddy soil), Yesan (non-cultivated soil), and Jungdong soil (upland soil). The soils were submerged with glucose sol'n at $28^{\circ}C$ for 17 days. After, the soils were incubated with phosphate solution at $25^{\circ}C$ for 24 hours. The seguential fractionation of inorganic phosphorus and of iron were conducted to investigate transformations of them. Results obtained are as follows; 1. By submergence, Bray I-P were decreased from 53mgP/kg to 48mgP/kg in Gangseo, from 3mgP/kg to 1mgP/kg in Yesan, and from 120mgP/kg to 56mgP/kg in Jungdong soil. 2. $NH_4F$ extractable P was dominant fraction of adsorbed P. It was transformed into NaOH extractable P by submergence in Jungdong soil. 3. Dithionite-citrate-bicarbonate extractable iron (crystalline Fe) was transformed to oxalate extractable iron (amorphous Fe) by submergence in Yesan soil.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.5
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• pp.13-20
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• 2008

Although digital hearing aid algorithms have been developed to compensate hearing loss and to help hearing impaired people to communicate with others, digital hearing aid user still complain about difficulty of hearing the speech. The reason could be the quality of speech through digital hearing aid is insufficient to understand the speech caused by feedback, residual noise and etc. And another thing is masking effect among formants that makes sound quality low. In this study, we measured the masking characteristics of normal listeners and hearing impaired listeners having presbyacusis to confirm masking effect in speech itself. The experiment is composed of 5 tests; pure tone test, speech reception threshold (SRT) test, word recognition score (WRS) test, puretone masking test and speech masking test. In speech masking test, there are 25 speeches in each speech set. And log likelihood ratio (LLR) is introduced to evaluate the distortion of each speech objectively. As a result, the speech perception became lower by increasing the quantity of formant enhancement. And each enhanced speech in a speech set has statistically similar LLR, however speech perception is not. It means that acoustic masking effect rather than distortion influences speech perception. In actuality, according to the result of frequency analysis of the speech that people can not answer correctly, level difference between first formant and second formant is about 35dB, and it is similar to result of pure tone masking test(normal hearing subject:36.36dB, hearing impaired subject:32.86dB). Characteristics of masking effect is not similar between normal listeners and hearing impaired listeners. So it is required to check the characteristics of masking effect before wearing a hearing aid and to apply this characteristics to fitting.

• Journal of Korean Society of Forest Science
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• v.89 no.1
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• pp.41-48
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• 2000

Mass loss and dynamics of mineral nutrient during decomposition of deciduous leaves and 3 species of needles were investigated for 38 months from October in 1992 to November in 1995 in Kwangneung, Korea. After 38 months, the remaining mass of deciduous leaves, Pinus koraiensis, Pinus rigida and Abies holophylla was 16.2%, 29.8%, 33.5% and 53.9%, respectively. The decay rate (k) of deciduous leaves, Pinus koraiensis, Pinus rigida and Abies holophylla was 0.61, 0.40, 0.37, $0.21yr^{-1}$, respectively. The lowest decay rate in fir needle might be, in part, due to low N concentration. N concentration of the decomposing litter increased during the experimental period except for P. rigida. Deciduous leaves showed a short immobilization period during the early stage of decomposition, and big-cone pine and pitch pine had no immobilization period. However, there was no net N mineralization in fir litter. P increased during the experimental period for all litter. Except for deciduous leaves, there was no net mineralization period. In case of deciduous leaves, however, remaining P after 38 months was 53% of the initial P capital. Remaining cations of the decomposing litter after 38 months were lower than those of initial contents.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.266-272
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• 1999

Aboveground biomass and nutrient contents of a 31-year-old pitch pine(Pinus rigida) and a 31-year-old Japanese larch(Larix leptolepis) plantations were measured in the Chungbu Forest Experiment Station, Kyunggi Province. Aboveground biomass was 170.2ton/ha in the pitch pine and 87.2ton/ha in the Japanese larch plantations. Aboveground biomass difference between both plantations was due to the difference of stand density. Aboveground biomass in both plantations was allocated as follows : stemwood>branch>stembark>needle. The concentrations of all nutrients(N, P, K, Ca, Mg) were generally higher in the Japanese larch needle than in the pitch pine because of high nutrient uptake characteristics of larch compared with pine tree species. The nutrient concentration in different tree tissues in both tree species decreased in the order of needle>branch>stembark>stemwood. Nutrient contents of aboveground biomass were : N, 335.9 ; P, 40.4 ; K, 121.4 ; Ca, 188.6 ; Mg, 93.8kg/ha in the pitch pine plantation, while nutrient contents in the Japanese larch plantation were : N, 226 ; P, 11.5 ; K, 72.9 ; Ca, 75.7 ; Mg, 37.1kg/ha. The nitrogen use efficiency calculated as the biomass produced by one unit of nitrogen was higher in the pitch pine than in the Japanese larch plantations. This result suggests that pine with high nitrogen use efficiency could be adapted in lower site productivity area compared with larch tree species.

• Korean Journal of Construction Engineering and Management
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• v.11 no.3
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• pp.125-133
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• 2010

Although work-efficiency of construction machinery is a critical factor for estimating its workable-quantity perunit time, the efficiency figure table presented in the Poom-Sam that is used for Construction Cost Estimation of public sectors in Korea is very subjective for practical usage. In order to suggest objective work-efficiency table for a Pump-Dredger, domestic and overseas documentary records were investigated and on-going construction sites were also visited. Moreover, actual work quantities collected from the site visits were compared with the ones calculated based on the Standard Measurement Methods used in Japan. The research found that the table can be revised by means of detailing down by several factors, namely project type, depth of soil, undersea-site shape, and condition on the sea for better estimation of its workable-quantity. The research will be the foundation for applying the rapid development of Construction Equipment and technology to the appropriate cost estimations and the ground work of related studies.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.1
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• pp.17-25
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• 1996

The results identified for bacterial flora 174, Vibrio spp.132, and coliform group 183 strains isolated from the areas of last China Sea and Yosu coastal sea during from August 6th. to 14th. 1992 were as follow: 40 strains among the 74 strains of bacteria flora isolated from fast China sea area were Pseudomonas spp.$(54\%)$ and 60 strains among the 100 strains isolated from Yosu sea area were Enterobacteriaceae $(60\%)$. Four strains were Vibrio alginoliticus and one strain of V, parahaemolyticus among 5 strains of genus Vibrio isolated from last China Sea. While 54 strains were V. alginolyticus $(43\%)$ and V, parahaemolyticus $(17\%)$ among 127 strains genus Vibrio isolated from Yosu coastal sea area. Seventy nine strains among the 156 strains of coliform group isolated from Vosu sea area were Escherichia coli I $(51\%)$ and each one strain Citrobacter freundii I and II. 3 strains among 27 strains isolated from last China sea area were E. coli$(11\%)$ and 1 strain of C. freundii I. Coliform group was grouped into 16 types by IMViC system, $44^{\circ}C$, gelatin liquefaction test.

• Economic and Environmental Geology
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• v.49 no.2
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• pp.89-95
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• 2016

Mo isotope, one of highly redox-sensitive isotopes, has been shown to be useful tracers of geochemical processes. Many studies for Mo isotope have documented with the help of recently developed analysis tools, but it has not yet been documented in the Korea. In this study, we introduce two-stage column separation method of Mo using column tube (BioRad PolyPrep(R) column, 10 ml) and anion exchange resin (BioRad Resin AG(R) 1-X8, 200-400 mesh). Mo isotope ratios in the solid SRMs (BHVO-2, SDO-1, PACS-2) and liquid SRM (IAPSO) were measured on MC-ICP-MS (Multi-collector Inductively Coupled Plasma Mass Spectrometer) and then compared with reference Mo isotope ratios. Mo isotope ratios in our study overlap with reference Mo isotope ratios within analytical error.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.177-182
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• 1989

The plant height, shoot numbers and dry matter weight in both bulrush and rice were increased by high level of nitrogen fertilizer and especially the dry matter weights in both species were sharply increased by high level of nitrogen fertilizer. The plant height, dry matter weight in rice, and shoot, and dry matter weight in bulrush were increased by high level of phosphorus fertilizer. The deficient symptom disappeared with change of low level into high level phosphorus in rice. The plant height, dry matter weight and shoot numbers in rice and bulrush were increased by high level of potassium fertilizer. In the inter-specific competition in bulrush according to various water levels, the plant heights in both species elongated longer with deep water levels, and the plant height and dry matter weight in bulrush were more sharply decreased than in rice by deep water levels. The shoot numbers and dry matter weight were critically dropped above 6-8 cm water level. In case of the shoot numbers for light source, in both species were more decreased in mixed culture than each monoculture. The exserted shoot length and weight in bulrush were larger than those in rice. The shaded shoot dry weight was more decreased in mixed culture than in each monoculture, and the decrement was larger in bulrush than in rice.

• Journal of Food Hygiene and Safety
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• v.31 no.1
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• pp.36-41
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• 2016

Ochratoxin A and aflatoxin may be detected from naturally fermented foods due to the contamination of the mycotoxin-producing molds or un-prudential use of the mycotoxin producing starter strains during the fermentation. This study was carried out to analyze the production of ochratoxin A and aflatoxin under the various environmental conditions. For the experiment, the effects of different temperature, culture media, and fermentation time on the production of ochratoxin A by Aspergillus usamii KFRI 999 and A. awamori KFRI 983 were analyzed. Additionally, the production of aflatoxin was assessed under the various temperature, initial pH, fermentation time and culture media during fermentation by A. flavus KACC 41403 and A. oryzae KACC 46471. The levels of ochratoxin A and aflatoxin were analyzed by HPLC. The result showed that the production of mycotoxin was greatly affected by the fermentation temperature. A. oryzae KACC 46471 did not produce aflatoxin. All of the mycotoxin producing strains showed the highest level of mycotoxin at $30^{\circ}C$. A. awamori KFRI 983 showed the lowest level of ochratoxin A in PDA media among the experimental medium. The results of the present study may be useful for the reduction of ochratoxin A and aflatoxin in various foods.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.312-315
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• 2006

축산물을 판매하고 있는 인터넷 및 통신판매업소에서 전자상거래 시 표지하여야 할 항목과 안전하고 위생적인 축산물의 확보를 위하여 표지하여야 할 항목으로 나누어 실태조사를 실시하였다. 전자상거래시 온라인(인터넷) 판매영업소가 표시하도록 규정하고 있는 항목 중에서 '상호명'과 '전화번호'를 제외한 나머지 정보는 일부 제품에서 누락되어 있는 것으로 나타났다. 특히 '배송비용 정보'(21% 미표시)와 '사이트 이용 약관'(23% 미표시)과 같은 정보는 상대적으로 높은 부적합률을 나타냈고, '이메일 주소'(22% 미표시)와 '팩스번호'(26% 미표시)의 부적합률은 가장 높게 조사되었다. 또한, 온라인 판매업소가 축산물을 판매할 때 표시하도록 규정되어 있는 항목 중에서 '제품명'과 '식육의 종류' 표시를 제외한 나머지 정보는 일부 제품에서 누락되어 있는 것으로 조사되었다. '식육의 부위'(19% 미표시)와 '제품의 구성'(27% 미표시)과 같은 정보는 상대적으로 높은 부적합률을 나타내었고, '보관방법'(57% 미표시), '품질보증 및 인증내용'(80% 미표시), '식육의 등급'(82% 미표시)과 같은 정보는 많은 제품에서 누락되어 있었으며, 특히 '제조일자'(95% 미표시)는 대부분의 제품에서 표기되어 있지 않은 것으로 조사되었다. 인터넷이나 통신판매업소를 통한 온라인 상거래에서는 육안으로 상품을 직접 확인할 수 없기 때문에 축산물의 위생 상태나 안전성을 파악하기 어려워 보다 확실하고 투명한 방법으로 축산물의 안전성과 위생 상태를 확인하는 수단으로 표시 규정을 100% 준수하여 품질의 고급화와 브랜드화를 이룩해 나가야 할 것으로 사료된다.타내었다.로 나타났다. 특히 골반골 현수는 출하 월령이 증가됨에 따라 관능 특성의 개선율이 높은 것으로 나타났다. 수 있다.분별을 성공적으로 수행하였다.(p<0.05), 맛, 연도, 다즙성 및 전체적인 기호성은 유의한 차이가 없었다.자체를 악하다고 볼 수 없고 더구나 구원을 이 세상에서의 이탈로 볼 수 없다. 진정한 구원이란 원래 하나님이 보시기에 아름다웠던 그 세상으로의 회복을 포함한다. 이런 면에서 하나님 주권 신앙 하에서 구원이란 전 인격적인 구원, 전 우주적인 구원이 된다. 그렇기 때문에 성도는 세상의 삶과 학문, 예술, 정치, 경제, 사회를 포함한 모든 분야를 하나님의 뜻 가운데서 그 원래의 목적에 부합할 수 있도록 회복시키는 일에 적극 참여해야 한다.자체가 이를 주도하기는 사실 어려움이 있다. 그리고 대형유통점이 영업행위를 영업시간제한에서부터 출점제한에 이르기까지 규제하는 건은 심사숙고하여야 한다. 대형유통점이 국가경제 및 지역사회에 미치는 영향이 부정적인가 긍정적인가에 대해 국내외 학계와 업계에서 여전히 많은 논란이 있기 때문이다. 정부와 지자체에 의한 시장개입은 반드시 필요한 경우에 한해 합당한 방법에 의해 이루어져야 한다. 대형유통점에 대한 규제는 지역사회에 미치는 영향을 다면적으로 평가한 결과에 근거하여 이루어져야 할 것이다. 대부분의 지자체는 체계적인 평가시스템과 객관적인 통계 자료를 갖고 있지 못한 실정이다. 향후 가장 시급한 과제는 시장개방 이후 지난 10년간 대형유통점이 지역사회에 미친 영향에 관한 광범위한 통계자료를 수집하고 이를 체계적으로 분석하여 정책방향을 올바르게 설정하는 것이라 할 수 있다.i와 K. pne