• Title/Summary/Keyword: 효율적

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Effects of Temperature, Relative Humidity, and Leaf Wetness Period on the Development of Rice Leaf Blast (잎도열병(稻熱病) 발생(發生)에 미치는 온도(溫度), 상대습도(相對濕度) 및 잎표면상(表面上)의 수분존재시간(水分存在時間)의 영향(影響))

  • Choi, W.J.;Park, E.W.;Lee, E.J.
    • Korean journal of applied entomology
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    • v.26 no.4 s.73
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    • pp.221-228
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    • 1987
  • The optimum temperature range for conidial germination of Pyriculacia oryzae on a slide glass was $26{\sim}30^{\circ}C$, at which at least four hours of leaf wetness period was required to germinate. Conidial germination was significantly reduced under dry conditions (relative humidity<85%) at $34^{\circ}C$ but not at lower temperature (18, 22, 26, $30^{\circ}C$). Number of lesions developed were greater at $26^{\circ}C$ than at other temperature tested. The average leaf wetness period required for production of a lesion per plant was 22 hours at $18^{\circ}C$, 16 hours at $22^{\circ}C$, 10 hours at $26^{\circ}C$, and 8 hours at $30^{\circ}C$. Less than one lesion per plant occurred at $34^{\circ}C$ even under 24 hours of leaf wetness period. The time period between inoculation and lesion appearance was $7{\sim}8$ days at $18^{\circ}C$, $4{\sim}5$ days at $22^{\circ}C$ and $26^{\circ}C$, and $3{\sim}4$ days at $30^{\circ}C$. The time period required for lesion appearance after inoculation was not affected by leaf wetness period and relative humidity. Lesion length increased most rapidly at $30^{\circ}C$ during the first four days after lesion appearance. Thereater, the rate of increase in lesion length was geratest at $26^{\circ}C$. The average increment of lesion length per day when relative humidity was greater than 90% was 0.7mm at $18^{\circ}C\;and\;22^{\circ}C$, 1mm at $26^{\circ}C$, and 0.8mm at $30^{\circ}C$. When relative humidity was less than 85%, the increments of lesion length per day were approximately $50{\sim}60%$ of those under humid conditions (relative humidity>90%) at all temperature regimes except $30^{\circ}C$. Relative humidity did not significantly affected lesion length at $30^{\circ}C$.

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A Study on Formulation of Surfactant-free Aqueous Cleaning agents and Evaluation of Their Physical Properties and Cleaning Ability (계면활성제 무첨가 세정제의 배합 및 물성/세정성 평가 연구)

  • Lee, Jae Ryoung;Yoon, Hee Keun;Lee, Min Jae;Bae, Jae Heum;Bae, Soo Jeong;Lee, Ho Yeoul;Kim, Jong Hee
    • Clean Technology
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    • v.19 no.3
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    • pp.219-225
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    • 2013
  • Environment-friendly and surfactant-free aqueous cleaning agents have been developed in order to solve various problems generated by surfactants in the aqueous cleaning agents. Aqueous surfactant-free cleaning agents, S-1 and S-2 have been formulated with water-soluble solvents such as propylene glycol and propylene glycol ether on their main components and with some additives. These solvents were chosen because of their good solubility in water and excellent solubility of fluxes which are major contaminants of printed circuit board in the electronic industry. Physical properties of the formulated and the imported cleaning agents were measured to predict their cleaning performance, and their cleaning abilities of flux and solder contaminants were evaluated under the various ultrasonic frequencies by a gravimetric method. The measurement results show that the physical properties of cleaning agent V are generally similar with those of formulated cleaning agents S-1 and S-2. Both the cleaning agent V and the formulated cleaning agents S-1 and S-2 showed similar trends that their pH decrease in the beginning and then increases later on with the increase of their dilution in water. It is considered that the wetting indices of the cleaning agents calculated with experimental values do not not have any influence on their cleaning ability. In ultrasonic cleaning tests under three ultrasonic frequencies of 28, 45, and 100 kHz, their best performances of cleaning solder and flux were obtained at 45 kHz and 28 kHz, respectively, and the cleaning performance of the formulated cleaning agents S-1 and S-2 was better than that of the cleaning agent V. However, in the case of the recommended diluted concentration of 25 wt% cleaning solution, the cleaning performance of the cleaner V for solder and flux was better in the initial stage of cleaning compared to the formulated cleaners. And it may be concluded that the formulated cleaning agents S-1 and S-2 can be applied to cleaning of solder and flux in the industry, based on the experimental results in this study.

A Study on the Utilization for Oral Health Education Materials of Dental Hygienists (치과위생사의 구강보건교육매체 활용 실태)

  • Jung, Young-ran;Jung, You-Sun;Han, Ji-Hyung;Hwang, Yoon-Sook;Choi, Hye-Sook
    • Journal of dental hygiene science
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    • v.11 no.1
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    • pp.23-30
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    • 2011
  • The purpose of this study was to examine the utilization of oral health education media among dental hygienists in charge of oral health education. The findings of the study were as follows. 1. In regard to the general utilization of educational media in possession by workplace, age and career, the dental hygienists who worked in public health clinics(42.4%), who were in their 40s and up(341.%) and whose career was six years or more(32.2%) made more use of the educational media. Those who didn't use the educational media cited time constraints as the most common reason(46.1%). 2. Models(53.2%) were highly preferred in most of the institutions where the dental hygienists worked, but the public health clinics(81.8%) and university hospitals(80.0%) were most fond of video clips. 3. Concerning preference for educational media by career, the dental hygienists whose career was between three and less than six years and who had a 10 years or more of career had the most liking for video clips, followed by models. Those whose career was between one to less than three years and between six and less than 10 years showed the most preference for models, followed by video clips. 4. As for their perception of the necessity of educational media, the majority felt the need for the media(87.5%). Regarding difficulties in purchasing necessary educational media, the biggest group pointed out a shortage of information(56.1%).

A Study of Radiation Exposure in Proton Therapy Facility (양성자치료기 가속기 시설에서의 작업종사자의 방사선 피폭 연구)

  • Lee, Sang-Hoon;Shin, Dong-Ho;Yoon, Myong-Geun;Shin, Jung-Wook;Rah, Jeong-Eun;Kwak, Jung-Won;Park, Sung-Yong;Shin, Kyung-Hwan;Lee, Doo-Hyun;Ahn, Sung-Hwan;Kim, Dae-Yong;Cho, Kwan-Ho;Lee, Se-Byeong
    • Progress in Medical Physics
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    • v.20 no.1
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    • pp.37-42
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    • 2009
  • Proton therapy facility, which is recently installed at National Cancer Center in Korea, generally produces a large amount of radiation near cyclotron due to the secondary particles and radioisotopes caused by collision between proton and nearby materials during the acceleration. Although the level of radiation by radioisotope decreases in length of time, radiation exposure problem still exists since workers are easily exposed by a low level of radiation for a long time due to their job assignment for maintenance or repair of the proton facility. In this paper, the working environment near cyclotron, where the highest radiation exposure is expected, was studied by measuring the degree of radiation and its duration for an appropriate level of protective action guide. To do this, we measured the radiation change in the graphite based energy degrader, the efficiency of transmitted beam and relative activation degree of the transmission beam line. The results showed that while the level of radiation exposure around cyclotron and beam line during the operation is much higher than the other radiation therapy facilities, the radiation exposure rate per year is under the limit recommended by the law showing 1~3 mSv/year.

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Evaluation on Thermal Performance Along with Constructability and Economic Feasibility of Large-diameter Cast-in-place Energy Pile (대구경 현장타설 에너지파일의 열교환 성능과 시공성 및 경제성 분석)

  • Park, Sangwoo;Sung, Chihun;Lee, Dongseop;Jung, Kyoungsik;Choi, Hangseok
    • Journal of the Korean Geotechnical Society
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    • v.31 no.5
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    • pp.5-21
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    • 2015
  • An energy pile is a novel type of ground heat exchangers (GHEX's) which sets up heat exchange pipes inside a pile foundation, and allows to circulate a working fluid through the pipe for exchanging thermal energy with the surrounding ground stratum. Using existing foundation structure, the energy pile can function not only as a structural foundation but also as a GHEX. In this paper, six full-scale energy piles were constructed in a test bed with various configurations of the heat exchange pipe inside large-diameter cast-in-place piles, that is, three parallel U-type heat exchangers (5, 8 and 10 pairs), two coil type heat exchangers (with a 500 mm and 200 mm pitch), and one S-type heat exchanger. During constructing the energy piles, the constructability of each energy pile was evaluated with consideration of the installation time, the number of workers and any difficulty for installing. In order to evaluate the thermal performance of energy piles, the thermal performance tests were carried out by applying intermittent (8 hours operating-16 hours pause) artificial cooling operation to simulate a cooling load for commercial buildings. Through the thermal performance tests, the heat exchange rates of the six energy piles were evaluated in terms of the heat exchange amount normalized with the length of energy pile and/or the length of heat exchange pipe. Finally, the economic feasibility of energy pile was evaluated according to the various types of heat exchange pipe by calculating demanded expenses per 1 W/m based on the thermal performance test results along with the market value of heat exchange pipes and labor cost.

The Effects of Obstructive Sleep Apnea Syndrome on Periodic Limb Movements in Sleep (폐쇄성 수면무호흡증이 주기성 사지운동증에 미치는 영향)

  • Seo, Cheon-Seok;Youn, Tak;Kim, Eui-Joong;Jeong, Do-Un
    • Sleep Medicine and Psychophysiology
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    • v.7 no.1
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    • pp.34-42
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    • 2000
  • Objectives: Periodic limb movements in sleep(PLMS) is a moderately prevalent disorder, of which pathophysiology remains largely unknown. PLMS has been reported to be common in patients with obstructive sleep apnea syndrome(OSAS), but reports on their relationship have been inconsistent in previous studies. Inconsistency of results may be attributable to insufficient number of the study subjects. We attempted to explore the influence of OSAS on PLMS in a large number of subjects. Methods: Three hundred and twenty subjects(M : F=192:128) with PLMS, as identified by the nocturnal polysomnography, were studied. Sample mean age was 53.1(SD=15.1) years and their mean periodic limb movement index(PLMI) is 25.2/hr (SD=24.8). PLMS subjects were divided into two groups, based on the presence or absence of OSAS. Periodic limb movement indices and sleep parameters between two groups were analyzed to evaluate the effects of OSAS on PLMS. Results: Each of PLMI and PLMI with arousal(PLMAI) correlated positively with age. PLMI of men was larger than that of women (p<0.01). The presence of comorbid OSAS independently had influence on PLMI(t=-2.20, p<0.05), but not PLMAI. There were no significant differences between the two groups in their PLMI, PLMAI and sleep parameters. However, the two groups differed in PLMI-correlated sleep parameters. In PLMS subjects with comorbid OSAS, PLMI was negatively correlated with each of slow wave sleep time and REM sleep time. In subjects without comorbid OSAS, PLMI was negatively correlated with sleep efficiency. Conclusion: PLMS patients with OSAS turned out to have increased PLMI than those without OSAS We suggest that OSAS patients may have subtle autonomic arousals and these arousals could, in part, express themselves as PLM.

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Transforming growth factor $(TGF)-{\beta}1$ conjugated chitosan film for enhanced osteoblastic activity (변형성장인자가 고정된 키토산 필름의 골아세포 활성에 미치는 영향)

  • Park, Yoon-Jeong;Lee, Jue-Yeon;Kim, Kyung-Hwa;Kim, Tae-Il;Lee, Myung-Hee;Shin, Seung-Yoon;Seol, Yang-Jo;Lee, Yong-Moo;Rhyu, In-Chul;Ku, Young;Han, Soo-Boo;Min, Byung-Moo;Lee, Seung-Jin;Chung, Chong-Pyoung
    • Journal of Periodontal and Implant Science
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    • v.34 no.4
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    • pp.781-790
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    • 2004
  • 골아세포의 생물학적 기능을 증진시키기 위해 키토산의 표면개질에 대하여 연구하였다. 생체적합성 천연고분자인 키토산은 1차 아미노기를 소유하고 있으므로 적정한 공유결합제를 사용하여 세포성장인자와 같은 생리활성을 지닌 단백질을 키토산의 표면에 고정시킬 수 있다. 본 연구에서는 키토산을 필름형태로 제조하여 세포성장인자 중 형질전환성장인자를 고정하고 골아세포의 부착, 성장 및 분화를 증가시키고자 하였다. 형태전환성장인자의 고정화 효율은 단순한 흡착방법에 비해 높았으며, 표면에 형성된 공유결합은 매우 안정하였다. 골아세포를 배양하여 초기세포부착능에 대한 영향을 연구한 결과, 배양 후 4시간, 1일째, 형질전환성장인자를 고정한 키토산 표면에서 고정하지 않은 키토산의 표면에 비해 더 많은 수의 골아세포가 부착되었고, 더 많이 신장된 부착형태를 보였다. 세포활성정도와 배양 후 4주일째의 칼슘축적량을 측정한 결과, 형질전환성장인자를 고정한 키토산 표면에서 고정하지 않은 키토산의 표면에 비해 더 높았다. 위의 결과는 키토산 표면에 형태전환성장인자의 고정이 성공적으로 이루어졌으며, 또한 실제로 활성이 있는 것이 증명되었다. 위의 연구 결과에서 형질전환성장인자로 고정된 키토산은 골아세포의 초기 부착 및 분화를 촉진시켰음을 알 수 있었던 바 성장인자의 표면고정은 임플란트 및 조직공학용 지지체에도 적용하여 생체적합성과 세포기능을 증진시키는데 이용할 수 있음을 알 수 있었다.

Studies on the Zanthoxylum piperitum $D_E$ $C_{ANDOLIE}$ - 1. Pungent principles and Essential oil composition - (천초(川椒)에 관(關)한 연구(硏究) - 1. 신미성분(辛味成分)과 정유성분(精油成分) -)

  • Jung, Hyun-Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.16 no.2
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    • pp.123-127
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    • 1987
  • The Pungent principles and Essential oil compositions of Zanthoxylum piperitum $D_E$ $C_{ANDOLIE}$(peel, barb) were analysed by HPLC and GC, respectively. Total Pungent principle contents of peels were about as 12 times as those of barks. The Sanshool I, Sanshool IV, Sanshool III and Sanshoo V were the major Pungent principles in the peels and barks. Besides, several Unknown Pungent principles were discovered in the peels and barks, too. Total Essential oil contents of peels were higher than those of barks at the ratio of 1.8 % to 0.5%. The Cineol+Limonene(37.7%) were the main Essential oil compositions in the peels, while ${\alpha}-Terpineol(16.5%)$ and Pinene(15.5%) were the major portion in the barks. The Essential oil of peels and barks were composed Pinen, Myrcene, Cineol+Limonene, Linalool, Isopulegol, Terpinen-4-ol, ${\alpha}-Terpineol$ and Piperitone. Besides, seven Unknown compositions were discovered, too.

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Drainage Analysis for the Anyang-cheon Upper-watershed Management Planning (유역관리계획수립(流域管理計劃樹立)에 관(關)한 기초적(基礎的) 연구(硏究))

  • Woo, Bo Myeong
    • Journal of Korean Society of Forest Science
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    • v.42 no.1
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    • pp.39-54
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    • 1979
  • Such stream characteristics as the numbers, lengths, orders of stream channels, and drainage density are the essential elements for the analysis of drainages in planning of watershed management in a drainage basin. The drainage net is the pattern of tributaries and master streams in a drainage basin as declineated on a planimetric map. Stream order is a measure of the position of a stream in the hierarchy of tributaries. Density of the drainage is given by the quotient of the cumulative length of stream and the total drainage area. Drainage density then is simply a length per unit of area. In this study, the Anyang-cheon upper-watershed is selected for the survey and analysis of the stream system and drainage density in view point of the useful collection of data for effective watershed management planning. The Anyang-cheon upper-watershed is consisted of about 12,600 hectars of drainage area including the 13 Sub-stream. Total length of the Stream (as described in the Stream Law) in the survey area is measured as much as 71.2km, and that of the Small-stream as descrived in the Saemaul Stream Survey Book (1972) is calculated as 43,010 meters. Besides of this lengths, measured about 43,410 meters of the Small-stream and about 71,900 meters of the Torrential valley through this study. The range of the drainage density among the 13 Sub-streams having sub-watershed is analysed as from 14.79 to 24.10, and average value of drainage density in the entire watershed is calculated as 18.21 in case of including the length of the Torrential valley and 12.50 in case of excluding the same. It is required that the standard classification system in classifing for the characteristics of identification among the Stream, Sub-stream, Small-stream, Torrent, and Torrential valley must be satisfied through joint study of the authorities concerned.

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Trends in Genetic Parameters with Age and Site for Early Implications of Genetic Improvement in Korean White Pine (잣나무의 유전적(遺傳的) 형질(形質) 개량(改良)의 조기검정(早期檢定)을 위한 수령(樹齡) 및 입지별(立地別) 생장(生長)과 유전모수(遺傳母數)의 특성(特性)에 관(關)한 연구(硏究))

  • Kim, Dae Eun;Chon, Sang Keun
    • Journal of Korean Society of Forest Science
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    • v.79 no.1
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    • pp.56-70
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    • 1990
  • Eighteen Korean white pine (P. koraiensis S. et Z.) families were tested in 3 different regions from age 5 to 9. Family and site were significant sources of variation for seedling survival and field growth, whereas the effects of family x site interaction ware relatively small as compared with the former sources of variation. Variance components estimated from the separate and combined sites indicated that the most variabilities were associated with individual trees within plot. Family ${\times}$ site interaction components as a percentage of family variance decreased sharply with age. Heritability estimates varied with testing site and tree age. Combined analyses, however, showed a moderate change in heritability with increasing tree ages, and demonstrated high and stable trends of estimates, particularly in family heritabilities of tree height ($h_F{^2}=0.789-0.798$). The gains estimated from combined analysis have expected maximum or near-maximum efficiencies at age 6 or 7. Given equal intensity of selection, mass selection showed the most efficient gains within and across the sites. However, for the differences between mass and combined selections are small, selection made on the combination of family and within-family would be more effective in improving genetic gains. Indirect selection method indicated that 5-and 6-years height were all good predictors of 9-year-old height with little loss of relative efficiency (less than 10%) as compared with direct family selection at age 9. Phenotypic and genetic correlations computed on the basis of family mean values of height and diameter have shown predominantly high, positive, and statistically significant (1% level) relationships between all tested pairs of traits, which indicates that family growth maintained statistically consistent trends with age. The best families are those that maintained a stable superiority overall sites and ages in growth performance, therefore, it can be suggested that early identification of superior families at age 9 is feasible at age 5 or 6 in Pinus koraiensis S. et Z.

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