• Title/Summary/Keyword: point to point (P2P)

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A Study on Runoff Properties of Non-point Pollutant in Nakdong watershed by using SWAT model (SWAT 모형을 이용한 낙동강 하구언의 비점오염물질 유출특성 규명)

  • Lee, Eun-Jeong;Choi, Kyoung-Sik;Kim, Tae-Keun
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.6
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    • pp.815-823
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    • 2012
  • Non-point source pollutants in down stream of Nakdong river were simulated by SWAT. GIS was utilized to make input data of SWAT such as landuse pattern and soil. Meteorological data of 2007 and 2009 were applied for the calibration and validation of runoff in SWAT. It was difficult to calibrate and validate the runoff and nutrient results since a study area was influenced by the tidal effects. Jindong site was selected to escape from the bias of runoff simulation in the coastal area. $R^2$ values of calibration and validation were 0.8 and 0.79. However, $R^2$ values of water qualities were very low level in comparison to runoff. These resulted from the concentration scale of water qualities such as BOD, T-N and T-P. Additionally, tidal influence could effected on the measurements of nutrients. The simulated annual averages and patterns of BOD, T-N and T-P in SWAT were similar to the measurement data. 80 ~ 96 % of nonpoint source pollutants at Nakbon M site were released from April to August of 2009. The ratio of T-N and T-P from nonpoint source were above 50 % during the rainy season.

CHEMICAL DEGRADATION AND WEAR OF LIGHT-CURED COMPOSITE RESINS (광중합형 복합레진의 화학적 분해와 마모에 관한 연구)

  • Yang, Kyu-Ho;Jung, Hee-Kyung;Choi, Nam-Ki;Kim, Seon-Mi
    • Journal of the korean academy of Pediatric Dentistry
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    • v.34 no.2
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    • pp.273-284
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    • 2007
  • The aim of this study was to evaluate the resistance to degradation and to compare the wear resistance characteristics of four esthetic restorative materials in an alkaline solution(0.1N NaOH). The composite resins studied were Composan LCM flow(Promedica, Germany). Clearfil ST(Kuraray medical, Japan), Durafi VS1(Heraeus Kulzer, U.S.A), Point 4(Kerr, U.S.A). The results were as follows : 1. The mass loss of each brand was $1.02{\sim}6.04%$ and highest value in Durafil VS$(6.04{\pm}0.29%)$. 2. The sequence of the degree of degradation layer depth was in descending order by Durafil VS, Clearfil ST, Point 4 and Composan LCM flow. There were significant differences between Point 4, Composan LCM flow and the others (p<0.001). 3. The sequence of the Si loss was in descending order by Clearfil ST, Durafil VS, Composan LCM flow and Point 4. There were significant differences among the materials (p<0.001). 4. On SEM, destruction of bonding between matrix and filler and on CLSM, the depth of degradation layer of specimen surface was observed. 5. The sequence of maximum wear depth was in descending order by Durafil VS, Composan LCM flow, Point 4 and Clearfil ST. There were no significant differences among the materials (p>0.001) 6. The correlation coefficient between Si loss and degradation layer depth (r=0.892, p<0.01) and Si loss and mass loss(r=0.736, p<0.01) were relatively high. These results indicate that hydrolytic degradation, wear and another factor may consider as evaluation factors of composite resins.

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Regime Shift of the Early 1980s in the Characteristics of the Tropical Cyclone Affecting Korea

  • Choi, Ki-Seon;Kim, Tae-Ryong
    • Journal of the Korean earth science society
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    • v.32 no.5
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    • pp.453-460
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    • 2011
  • By performing a statistical change-point analysis of activities of the tropical cyclones (TCs) that have affected Korea (K-TCs), it was found that there was a significant change between 1983 and 1984. During the period of 1984-2004 (P2), more TCs migrated toward the west, recurved in the southwest, and affected Korea, compared to the period of 1965-1983 (P1). These changes for P2 were related to the southwestward expansion of the subtropical western North Pacific high (SWNPH) and simultaneously elongation of its elliptical shape toward Korea. Because of these changes, the central pressure and lifetime of K-TC during P2 were deeper and longer, respectively, than figures for P1. This stronger K-TC intensity for P2 was related to the more southwestward genesis due to the southwestward expansion of the SWNPH. The weaker vertical wind shear environment during P2 was more favorable for K-TC to maintain a strong intensity in the mid-latitudes of East Asia.

On the Fixing of the Shoulder Blade Level during Tight Fitting by the Draping Design (입체 재단법에 의한 Tight Fitting시 등폭 기준선의 설정에 관한여)

  • 이순섭
    • The Research Journal of the Costume Culture
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    • v.4 no.3
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    • pp.373-381
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    • 1996
  • Draping design system organized by European about 13C has been developed greatly for a long while, but for the purpose of the practical use the Dress form similar to human body has been needed. In order to make three-dimensional effect as fitting Muslin ot the Dress form. the Basic lien has to be established in Muslin and Dress form each. At this time, Shoulder-blade level is indicated from various angles : measure down 10cm from the back neck point, a quarter of the back neck point to the waist lie, the half-way point between neckline and bust line, measure down 41 inches from the back neck line, measure down 3 inches from the top edge of the muslin at center back and cross mark for neck line, and so forth. This study established the Basic line through the two ways of them (B.N.P∼B.L/2, B.N.P∼W.L/4), did tight fitting to the 5 kinds of Dress forms which ar normal type in the drop value(the difference between hip circumference and bust circumference), and acquired Basic Pattern. After the experiment, fitness are throughly investigate by statistical analysis of measurements. As a result, this study finds out that fit is proper when shoulder blade level is situated on a fourth of the back neck point to the waist line and a quarter point between back neck point and waist line, and waist dart is situated on the back center line and princess line.

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Assessment of Non-point Pollutants and Runoff Characteristics in Urban Area, Korea

  • Park, Jae-Young;Choi, I-Song;Oh, Jong-Min
    • Korean Journal of Ecology and Environment
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    • v.38 no.spc
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    • pp.67-75
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    • 2005
  • The objectives of this study were to understand the runoff characteristics of the non-point sources originating from impervious surfaces and to assess their effect on the aquatic environment in the urban areas. The concentration of pollutants (SS, BOD, COD and T-P) except for T-N showed the highest value in runoff from road, and event mean concentration (EMC) also showed high value from road. The pollutants discharged from road showed a higher concentration in the beginning stage (0 ${\sim}$ 30%) of progressive percentage of rainfall. The contribution percentages of non-point sources by load were 44.9% for SS, 11.2% for BOD, 21.4% for COD, 11.4% for T-N and 8.1% for T-P in the total load of pollutant discharged through sewer. From our results, the road was a significant potential source that deteriorated water quality of the streams and lakes in the vicinity of the urban area during the rain period. Therefore, counter plan is required to reduce pollutant concentration on the road from non-point sources in the urban area. Also, since pollutant concentration in the beginning stage of rainfall was quite high, road cleaning seems to be one of the very useful methods to prevent inflowing of pollutants to the aquatic environment.

Psychological Well-being, Perceived Health Status, and Health Promoting Behavior of Clinical Nurses (임상간호사의 심리적 안녕감, 지각된 건강상태, 건강증진행위에 관한 연구)

  • Choi, Yune-Jung;Sung, Young-Hee
    • Journal of Korean Academy of Nursing Administration
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    • v.19 no.5
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    • pp.589-598
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    • 2013
  • Purpose: This study was designed to assess the degree of psychological well-being, perceived health status, and health promoting behavior of clinical nurses, and to identify correlations between variables. Methods: Participants were 194 nurses working at S hospital, Seoul and data were analyzed using descriptive statistics, ANOVA, Duncan's test, Pearson correlation coefficient, and multiple regressions. Results: Mean scores were 3.45 (5 point scale) for psychological well-being, 2.82(4 point scale) for perceived health status, and 2.30(4 point scale) for health promoting behavior. Psychological well-being correlated positively with perceived health status (r=.34, p<.001). Perceived health status showed a positive correlation with health promoting behavior (r=.30, p<.001). There was a positive correlation between psychological well-being and health promoting behavior (r=.52, p<.001). Personal growth(t=2.85, p=.005), purpose in life (t=2.30, p=.023) among subscales of psychological well-being, and perceived health status (t=2.13, p=.034) had a significant influence on health promoting behavior. These combinations explained 32.1% of health promoting behavior (F=12.58, p<.001). Conclusion: The results of this study suggest strategies to improve health promoting behavior by enhancing psychological well-being of nurses. Furthermore, a study to identify the effects of developed and applied psychological well-being promotion program should be conducted.

A Variable Latency Newton-Raphson's Floating Point Number Reciprocal Square Root Computation (가변 시간 뉴톤-랍손 부동소수점 역수 제곱근 계산기)

  • Kim Sung-Gi;Cho Gyeong-Yeon
    • The KIPS Transactions:PartA
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    • v.12A no.5 s.95
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    • pp.413-420
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    • 2005
  • The Newton-Raphson iterative algorithm for finding a floating point reciprocal square mot calculates it by performing a fixed number of multiplications. In this paper, a variable latency Newton-Raphson's reciprocal square root algorithm is proposed that performs multiplications a variable number of times until the error becomes smaller than a given value. To find the rediprocal square root of a floating point number F, the algorithm repeats the following operations: '$X_{i+1}=\frac{{X_i}(3-e_r-{FX_i}^2)}{2}$, $i\in{0,1,2,{\ldots}n-1}$' with the initial value is '$X_0=\frac{1}{\sqrt{F}}{\pm}e_0$'. The bits to the right of p fractional bits in intermediate multiplication results are truncated and this truncation error is less than '$e_r=2^{-p}$'. The value of p is 28 for the single precision floating point, and 58 for the double precision floating point. Let '$X_i=\frac{1}{\sqrt{F}}{\pm}e_i$, there is '$X_{i+1}=\frac{1}{\sqrt{F}}-e_{i+1}$, where '$e_{i+1}{<}\frac{3{\sqrt{F}}{{e_i}^2}}{2}{\mp}\frac{{Fe_i}^3}{2}+2e_r$'. If '$|\frac{\sqrt{3-e_r-{FX_i}^2}}{2}-1|<2^{\frac{\sqrt{-p}{2}}}$' is true, '$e_{i+1}<8e_r$' is less than the smallest number which is representable by floating point number. So, $X_{i+1}$ is approximate to '$\frac{1}{\sqrt{F}}$. Since the number of multiplications performed by the proposed algorithm is dependent on the input values, the average number of multiplications Per an operation is derived from many reciprocal square root tables ($X_0=\frac{1}{\sqrt{F}}{\pm}e_0$) with varying sizes. The superiority of this algorithm is proved by comparing this average number with the fixed number of multiplications of the conventional algorithm. Since the proposed algorithm only performs the multiplications until the error gets smaller than a given value, it can be used to improve the performance of a reciprocal square root unit. Also, it can be used to construct optimized approximate reciprocal square root tables. The results of this paper can be applied to many areas that utilize floating point numbers, such as digital signal processing, computer graphics, multimedia, scientific computing, etc.

A Study on Accuracy in Determining the Hinge Axis Location (접번축(蝶番軸) 위치(位置) 결정시(決定時)의 정밀성(精密性)에 대(對)한 연구(硏究))

  • Kim, Choon-Ho;Kay, Kee-Sung
    • The Journal of Korean Academy of Prosthodontics
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    • v.24 no.1
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    • pp.17-26
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    • 1986
  • The purpose of this study was to investigate true hinge axis location with different times (8:00-9:00 A.M.,2:00-3:00 P.M.) and with experienced and inexperienced groups. 25 subjects, 23-27 years of age , with functionally acceptable occlusion, and no clinical signs of temporomandibular joint dysfunction were participated in this study. In this study arbitrary hinge axis point was located 13 mm anterior to the posterior margin of the tragus on a line from the center of the tragus to the outer canthus of the eye and then the true hinge axis point was located with T.M.J. hinge axis locator. The discrepancies of distance and the direction between true hinge axis point and arbitrary hinge axis point were studied according to times and two groups. The results obtained were as follows : 1. The mean distance from arbitrary hinge axis point to the true hinge axis point on the right and left sides was as follows : Experienced group: linear distance: $1.228{\pm}3.145mm$, vertical distance: $-1.128{\pm}2.515mm$, horizontal distance: $-0.484{\pm}1.806mm$. Inexperience group: linear distance: $1.628{\pm}3.158mm$, vertical distance: $-1.169{\pm}2.090mm$, horizontal distance: $-1.133{\pm}2.367mm$. Horizontal distance between experienced and inexperienced groups was significant statistically. (P<0.1) 2. True hinge axis points located within 5 mm of arbitrary hinge axis point were 86.7% in the experienced group and 84% in the inexperienced group. 3. For experienced operator A with time, the mean distance from arbitrary hinge axis point to true hinge axis point was as follows: Horizontal distance: AM: $-0.613{\pm}1.966mm$, PM: $-0.860{\pm}2.156mm$. Vertical distance: AM: $-0.886{\pm}2.518mm$, PM : $-1.226{\pm}2.660mm$. True hinge axis points had tendency to be located posterior-inferiorly to tragus-canthus line in the afternoon than in the morning, but there was not significant statistically. (P>0.1)

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A research of dental hygienists' recognition on dental infection (치과위생사의 치과감염에 대한 인식도 조사)

  • Lee, Ka-Yean;Lee, Jung-Ae
    • Journal of Korean society of Dental Hygiene
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    • v.9 no.1
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    • pp.45-58
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    • 2009
  • The purpose of this study was to examine the recognition level related to the infection prevention in dental medical institute in dental hygienists and to offer basic data of enhancing the knowledge education in dental hygienists on the infection prevention according to it. As a result of collecting and analyzing data by using the self-administered questionnaire on April 27, 2008 targeting 230 dental hygienists who are working at hospitals and clinics in P,K region, the following conclusions were obtained. 1. Dental hygienists' recognition on hospital-virus treatment method was indicated to be averagely 1.20 out of 3-point perfection. 2. The recognition on infection was indicated to be averagely 2.64 out of 4-point perfection. The statistically significant difference was shown with the appearance of periodical health examination(t=-2.42, p<.05) and by infection-education experience(t=2.28, p<0.05). 3. The recognition on an infection disease was indicated to be averagely 4.38 out of 8-point perfection. The significant difference(t=3.52, p<0.05) was shown depending on task in charge. 4. The recognition on the infection prevention in dental treatment institute was indicated to be averagely 4.89 out of 7-point perfection. The recognition on the infection prevention of dental treatment institute in dental hygienists, who work for general hospital, was indicated to be the highest. Accordingly, it was considered to be required an effort for dental hygienists, other dental-medical practitioners, and patients to be able to treated safely by enhancing the recognition level on infection prevention in dental hygienists and by maximally reducing exposure to infection in dental medical institute.

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