• The Journal of the Korea Contents Association
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• v.16 no.8
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• pp.419-426
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• 2016

The research is done to analyze the change of personal dosimeter according to the elapsed times(24 hours, 1 week, 2 weeks, 3 weeks, 4 weeks) and magnetic field and find out the effective exposure treatment for radiation workers. At first, research the heat treatment and radiation of grouped TLD and keep them in different environments-exposed separately to observe the consequences of glow curve and the level of radiation exposure. As a result, we could find that 24 hours passing TLD group showed the difference in glow curve and the level of radiation. This can be considered as the change caused by magnetic exposure. Also the average radiation exposure level of TLD group, unexposed to the magnetic field, was 15.41 mSv. And the average radiation exposure level of TLD group, exposed to the magnetic field, was 14.83 mSv which decreased the biggest amount(3.80%) among the other groups. If a radiation worker, who works in PET-MRI room, uses TLD as a personal dosimeter, the level of real radiation exposure caused by exposure to the magnetic field won't change significantly as recorded at a regular record cycle but with not regular record but interim record, the lower exposure dose will be appeared than the real level of radiation.

• Journal of the Korean Home Economics Association
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• v.26 no.1
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• pp.83-96
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• 1988

科學의 발전과 經濟의 高度成長으로 食生活의 向上은 人間의 수명을 크게 연장시키고 있다. 韓國에 있어서도 이러한 傾向은 같은 樣相이며 더욱이 보건형태가 차차 변경되어 가고 있다. 女性의 平均수명은 男性보다 길며 近來에 이르러 女性人口의 95%가 閉經을 經驗할 때까지 生存하고 있다고 한다. 이러한 실정임에도 불구하고 우리나라 女性의 閉經年令, 更年期에 處한 婦人들의 건강 및 營養攝取狀態, 食生活 態度등에 關한 情報가 파악되어 있지 않고 있다. 本 硏究는 이 點을 감안하여 우리나라의 中年女性의 건강管理의 指針을 세우기 위하여 생물학적 요인 및 환경적 요인이 閉經年令 및 更年期婦人의 건강狀態와 食行動에 어떠한 영향을 미치는지를 검토하여 보았다. 本 硏究는 1980년 12월에서 1981년 2월까지 3개월간 韓國의 2個의 大都市와 5個의 小都市에 거주하는 40歲에서 60歲까지의 女性을 대상으로 설문지를 통해 다음과 같은 사항을 조사하였다. 조사내용으로 1) 폐경연령, 주거환경, 사회경제적 조건, 체위, 임신횟수, 유산경험의 유무 2) 건강상태, 갱년기 자각증상, 유경시 월경의 순, 불순상태 그리고 3) 영양섭취상태와 식행동 등이다. 本論文은 調査內容 中 第 2 報로 更年期女性의 영양섭취상태와 식생활 행동 그리고 更年期 현상과의 關係를 關例시켜 검토하였다. 간이식품 섭취 사항 조사표를 사용하여 영양소의 섭취상태를 조사한 결과 大都市群은 energy, 지방, thiamin 및 ascorbic acid 의 섭취상태가 그 對照群에 比하여 높은 경향을 나타냈다. 열양 구성비에 대한 검토를 보면 糖質:蛋白質:脂肪(C:P:E)의 比가 64~67%:14%:19%~22%였으며 大都市群은 小都市群에 比해 脂肪에서의 energy섭취가 유의적으로 높았다. 더욱이 사회 경제적 측면으로 보아도 지방섭취는 저소득층에서 낮은 경향을 보여주었다. 更年期女性의 음식에 대한 기호變化의 검토를 통해 관찰한 것에 의하면 閉經者가 未閉經者에 比해 더 많이 食品嗜好의 變化를 경험하고 있다고 지적\ulcorner\ulcorner있다. 37.4%와 28.1%가 각기 기호의 變化를 경험하고 있었으며 이는 兩群間에 有意차가 높음을 보여주었다. 閉經 후 2年頃부터 食品의 嗜好變化를 느끼고 있다고 하는 사람이 많았으며 음식은 기름기 있는 것보다 담백한 것, 肉類보다는 生鮮, 果實, 野菜를 더 선호하는 경향이라고 하였다. 자극성이 있는 것에서 덜 자극성 있는 것을 찾는 경향이었다. 이들의 食品선택구조를 파악하는 것은 그 지역의 특수한 영양문제뿐만 아니라 그들의 영양교육, 더 나아가서는 그 지역의 식량영양정책 수립을 위해 중요한 정보를 제공할 수 있다. 大都市群은 肉類, 卵類, 乳類 및 그 製品등의 선택과 빵이나 butter 등의 食品과 正의 相關性을 나타내고 있었으나(p<0.01) 김치와 같은 韓國의 傳統的 食品의 선택時는 乳類, 果實, 빵과 같은 近代的 感覺의 食品과는 負의 相關性을 나타냈다. 한편 김치는 밥 및 기타 곡류 그리고 서류와는 正 相關性을 시사하였다. 小都市群은 對照群과는 多少 상이한 식품선택 구조를 보이고 있다. 즉 卵類나 乳類를 섭취할 수 있는 사회경제적 조건, 그리고 기호를 갖는 사람들은 서류를 제외한 모든 식품과 正의 相關性을 나타냈다. 어느 群이든 밥과 김치는 높은 相關性을 나타내고 있으며, 이 두 식품은 韓國人의 食生活의 基本이 되고 있으며 이를 土臺로 다른 食品의 선택은 地域的, 社會經濟的, 그리고 個人의 기호에 따라 다르게 나타난다는 것이 시사되었다. 閉經前 後의 更年期라는 것은 30餘年 間의 性 hormone의 周期的分泌에 依한 月周期가 停止하는 時期이며, 內分泌環境의 變化에 依한 生體 리듬의 異常은 各種 更年期증상의 원인이 되고 있다. 有經時의 月經주기의 이상을 경험하는 사람에게 특히 更年期증상中 食慾不振이나 不眠 등의 不平 數가 많았다. 이러한 점으로 미루어 보아 estrogen과 食慾과의 相關性은 높음이 시사되었다. 이는 不眠症과는 연관성이 있으며 性홀몬 分泌의 亂脈은 食事攝取의 리듬을 흐틀어 놓으며 이것이 生體리듬의 變化를 유발한다고 본다.

• 한국해양학회지
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• v.30 no.5
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• pp.442-457
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• 1995

The relationships of environmental factors to the distribution patterns of the three species of ophiuroids, Ophiura kinbergi, O. sarsi and ). sarsi vadicola from Yellow Sea southeast seas and East Sea of Korea were studied to characterize their habitual niches. These three species chosen for study illustrated distinct niche and patterns according to their various preferences mainly for bottom water temperature, bottom water salinity and depth from seven environmental variables which were depth, bottom water temperature and salinity, density, bottom water oxygen content, grain size of the surface sediment, and sediment sorting coefficient. The results of habitat niche study mainly dealing with O. sarsi vadicola suggested that the optimum habitat rages were approximately 6$^{\circ}C$∼10$^{\circ}C$ in bottom temperature and 31%∼33.5% in bottom water salinity which also corresponded with the characteristic ranges of Yellow Sea Bottom Cold Water and higher probabilities of occurrence (more than 70%) were found in depth ranging from 100 to 200 m. In addition, the habitats of O. kinbergi and O. sarsi were compared with that of O. sarsi vadicola. Their ranges of habitat niches were found to have different niches in physical space of bottom water temperature, bottom water salinity and depth. Based on the distribution pattern of O. sarsi vadicola in the Yellow Sea, the ecological barrier which confined the distribution of benthic macro-invertebrates in southern Yellow Sea was determined to be the Yellow Sea Warm Current (approximately 34% < and 18$^{\circ}C$ in December) which occurs between 33$^{\circ}$ and 34$^{\circ}$N of southern Yellow Sea in winter time.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.2
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• pp.109-115
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• 2006

Understanding characteristics of claypan soils has long been an issue for researchers and farmers because the high-clay subsoil has a pronounced effect on grain crop productivity. The claypan restricts water infiltration and storage within the crop root zone, but these effects are not uniform within fields. Conventional techniques of identifying claypan soil characteristics require manual probing and analysis which can be quite expensive; an expense most farmers are unwilling to pay. On the other hand, farmers would be very interested if this information could be obtained with easy-to-use field sensors. Two examples of sensors that show promise for helping in claypan soil characterization are soil profile strength sensing and bulk soil apparent electrical conductivity (ECa). Little has been reported on claypan soils relating the combined information from these two sensors with grain crop yield. The objective of this research was to identify the relationships of sensed profile soil strength and soil EC with nine years of crop yield (maize and soybean) from a claypan soil field in central Missouri. A multiple-probe (five probes on 19-cm spacing) cone penetrometer was used to measure soil strength and an electromagnetic induction sensor was used to measure soil EC at 55 grid site locations within a 4-ha research field. Crop yields were obtained using a combine equipped with a yield monitoring system. Soil strength at the 15 to 45 cm soil depth were significantly correlated to crop yield and ECa. Estimated crop yields from apparent electrical conductivity and soil strength were validated with an independent data set. Using measurements from these two sensors, standard error rates for estimating yield ranged from 9 to 16%. In conclusion, these results showed that the sensed profile soil strength and soil EC could be used as a measure of the soil productivity for grain crop production.

• Journal of Korea Water Resources Association
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• v.46 no.1
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• pp.35-45
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• 2013

The aim of study is to present how to estimate and use the FRI (Flood Risk Index) for classifying area zones based on regional flooding risk in terms of the integrated flood risk management. To estimate the FRI at a spatial resolution of city/county/town units for the Nakdong River Watershed, the 17 representative flood indexing factors are carefully selected for the three flood indexes, such as PI (Pressure Index), SI (State Index), and RI (Response Index) under the P-S-R (Pressure-State-Response) classification system. Because flood indexing factors are measured at different scales and units, they are transformed into a common domain by the T-Score normalization technique. The entropy weight coefficient method is also applied to calculate the weight of flood indexing factors in order to reduce subjective judgement on the effect of weight coefficients. The three flood indexes of PI, SI, and RI are integrated for an overall value of the FRI to evaluate the flood risk of districts. To examine the practical application of the proposed FRI, the FRI results with/without the weight coefficients are compared with flooding zones of natural disaster risk areas officially announced in 2010. It is expected that the FRI ensured by full verification can make regional protection plans against flooding disasters with respect to causes and characteristics of past floods.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2C
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• pp.246-253
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• 2010

In this paper, a method of removing the space skew and cross-talk cancellation is proposed where the self-generated signals from the subject are used to obtain the subject's location. In the proposed method, the good spatial sound image is maintained even when the listener moves from the sweet spot. Two major parts of the proposed method are as follows: listener position tracking using the stimuli from the subject and removal of the space skew and cross-talk signals. Listener position tracking is achieved by estimation of the time difference of arrival (TDoA). The position of the listener is then computed using the Talyer-series estimation method. The head-related transfer functions (HRTF) are used to remove the space skew and cross-talk signals, where the direction of the HRTF is given by the one estimated from the listener position tracking. The performance evaluation is carried out on the signals from the 100 subjects that are composed of the 50 female and 50 male subjects. The positioning accuracy is achieved by 70%~90%, under the condition that the mean squared positioning error is less than $0.07m^2$. The subjective listening test is also conducted where the 27 out of the 30 subjects are participated. According to the results, 70% of the subjects indicates that the overall quality of the reproduced sound from the proposed method are improved, regardless of the subject's position.

• Korean Journal of Veterinary Research
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• v.36 no.3
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• pp.665-680
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• 1996

Bovine Pneumonic Pasteurellosis는 수송열(輸送熱)로 일반적으로 알려져 있는 질병으로서, 여러가지 요인의 복합적(複合的)인 작용에 의해 발병하는 것으로 알려져 있으나, Pasteurella haemolytica A1이 가장 주요(主要)한 인자(因子)로 밝혀져 있다. P haemolytica A1은 leukotoxin(LKT), lipopolysaccharide(LPS), capsular polysaccharide 등 여러가지의 병원성인자(病原性因子)을 생성한다. 이들 인자중 LKT가 가장 중요한 병원성인자로 밝혀져 있다. 이에 본 실험은 P haemolytical A1의 LKT 유전자를 Bacillus subtilis에서 발현(發現)시킴으로서 LPS에 오염(汚染)되지 않은 LKT을 대량으로 생산할 목적으로 실시되었다. 실험의 첫 단계(段階)로서 pLKT52 plasmid을 Sau3 A1의 제한효소을 이용하여 부분소화(部分消化)시킨 후 이 부분 소화(消化)된 유전자들로부터 3~5kb 크기의 유전자들을 순수분리하여 pUC18와 결합시킨 후 E coli NM522에 형질전환(形質轉換)시켰다. 이때 형질전환된 균주들은 LKT에 대한 단크론 항체인 MAb601을 이용하여 colony blot 법에 의해서 LKT 유전자 보유 및 발현여부(發現與否)을 조사하였다. 이들 양성 clone들은 제한효소분석(制限酵素分析), 염기서열분석(鹽基序列分析) 및 Western blot 등에 의해서 재확인(再確認)하였다. 총 9개의 양성 clone중 위의 방법에 의해서 한 clone을 선택(選擇)하여 lktCA insert를 재분리하여 shuttle vector에 subcloning 하였다. Subcloning된 LKT 유전자들은 shuttle vector의 종류(種類)(pHPS9, p602/20, pHPS9-Sac)와 각기(各其) 다른 종류(種類)의 B subtilis(spoO12A, BR121, WB3O, Raj1105) 숙주내(宿主內)에서 발현정도를 Western blot 법에 의해서 비교(比較)하였다. 이때 최적발현조건(最適發現條件)은 p602/20와 pBL1의 dual plasmid system을 이용하여 B subtilis spoO12A에서 2시간동안 IPTG로 발현을 유도(誘導)하는 것이었다. B subtilis에서 발현된 LKT을 visual 법과 neutral red uptake 법을 이용하여 소 폐포(肺胞) 대식구(大食求)에 대한 biological activity를 확인하였다. 발현된 LKT에 대한 LPS 오염은 LKT을 SDS-PAGE 후 silver stain에 의해서 확인하였다. 본 실험을 통해서 볼 때에 lktCA 유전자를 보유(保有)하고 있는 p602/20는 B subtilis에서 매우 불안정(不安定)하였고, 발현된 LKT는 세균자체(細菌自體)에서 생성되는 protease들에 의해서 파괴(破壞)됨으로서 농도(濃度)가 매우 낮았다. 이러한 문제점들은 다음 단계(段階)의 실험에서 해결되어야할 문제들이다.

• Journal of radiological science and technology
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• v.34 no.4
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• pp.351-357
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• 2011

The $^{18}F$-FDG is one of the widely used isotopes for PET/CT scans. Dose amount injected to the patient depends on the characteristics of PET/CT systems. Obviously, the technologists who contact with patients would be exposed as well. In this study, we evaluated the exposed dose of the technologist who works on the PET/CT scanner. The exposed dose were measured every month with the TLDs from 6 technologists. Each technologist is shift-worker who manages 3 different PET/CT systems(Scanner 1(S1): 0.15 mCi/kg, Scanner 2(S2): 0.17 mCi/kg, Scanner 3(S3): 0.12 mCi/kg). The average exposed doses of technologists for each PET/CT system were measured as 0.76 mSv for S1, 0.93 mSv for S2 and 0.47 mSv for S3. The maximum dose was 1.12 mSv and minimum was 0.42 mSv. The results showed that there was a correlation between exposed dose and PET/CT system(p<0.005). Less injected dose for patient occurs less exposed dose for technologist. Various studies for the low dose PET/CT system are required for not only the patient but also the technologist.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.533-541
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• 2005

Non-aqueous cleaning agents were formulated with 2,2,2-trifluoroethanol (TFEA) and hydrofluoroether (HFE), and their physical properties and cleaning abilities were examined. TFEA-based aqueous cleaning agents were also formulated with nonionic surfactants, hydrotropes and builders, and their cleaning abilities were compared. Possibilities of these cleaning agents as substitutes for CFC-113 and 1,1,1-TCE were finally evaluated. In this work, fluxes, cutting oils, greases, and fluoric oils were selected as model contaminants for cleaning experiments. These contaminants have different properties of water-solubility or hydrophilicity, and fat-solubility or lypophilicity. Cleaning abilities of TFEA-based cleaning agents were analyzed and compared through the measurement of contaminant weight changes as a function of cleaning time, and their possibilities as alternative cleaning agents were evaluated. As a result, it was shown that TFEA and HFE-based non-aqueous cleaning agents have quite a good cleaning power for fluxes and fluorine soils but low one for greases. And TFEA-based agueous cleaning agents which consisted of nonionic surfactants, hydrotrope, and builders were very effective for cleaning fluxes and greases under certain formulation conditions. Thus, it was revealed that the TFEA-based cleaning agents were very effective for cleaning specific contaminants and can be used as substitutes for CFC-113 and 1,1,1-TCE in some industrial applications.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.347-359
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• 2021

This study was intended to conduct a prospective study on the P2P Car-sharing service, which will be established as a new business model in the future, by identifying consumers' intention to accept the technology for the P2P-based Car-sharing service that will be introduced and spread in earnest in the future. The main results are as follows. First, the quality characteristics of the P2P Car-sharing service all have a statistically significant positive(+) effect on the perceived usefulness and ease of use of users, and among the quality characteristics, the service characteristics have a relatively strong effect on the perceived usefulness and ease of use, respectively. Second, both perceived usefulness and ease of use had a statistically significant positive(+) effect on users' intention to use P2P Car-sharing service, and ease of use was more dependent on intention to use P2P Car-sharing service. Third, the ease of use of the P2P Car-sharing service had a strong positive(+) effect on their perceived usefulness. As a result of this study, the most important factor to consider in establishing a P2P-based Car-sharing platform is to be constructed in the form of a universal design that prioritizes user convenience rather than usefulness and various functions of the service. It was suggested that UX design should be made, considering the surrounding clues, which are service environment elements.