• 한국작물학회지
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• 제3권
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• pp.41-48
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• 1965

수도출수기의 년차간변이정도를 알고 아울러 출수기의 조기예측방법을 연구검토코자 1959년부터 1964년까지 6개년간에 걸쳐 관산외 5개품종을 공시하여 작물시험장 답작과(수원)에서 실시한 조기ㆍ보통기 및 만기 재배시험성적과 1953년부터 1964년까지 12갠년간에 걸쳐 각도에서 실시한 수도풍흉고조시험성적으로부터 품종별로 매년의 출수기를 조사정리하고, 아울러 당해연도 해지방의 기상통계를 조사정리하여 출수기의 변이와 기상요인과의 관계를 연구검토하여 출수기의 조기예측방법을 모색코자 시도한 것으로서 그 결과는 다음과 같다. 1. 수도출수기의 년차간변이 : 이것은 조기재배에 있어서는 14∼21일로서 대단히 크며, 보통기재배에서는 7∼14일 정도이고, 만기재배에 있어서는 1∼7일 정도로서 어느 재배시기보다 적으며, 그정도는 품종ㆍ재배시기 및 지역 등에 따라 차이기 있다. 2. 수도출수기의 조기예측 : 조기재배에 있어서는 공시전품종 파종후 31일부터 40일간의 적산온도와 출수일수간에 가장 높은 부의 상관을 가지고 있으며, 따라서 이 기간의 적산온도 및 회귀 직선식(Y=a+bX)의 산출에 의하여 실용적출수기를 조기에 예측할 수 있다고 생각된다. 그러나 만생종에 대하여 앞으로 더욱 검토하여야 할 것이다. 보통기재배에 있어서는 수원에서의 6개년간 성적에 의하면 적산온도와 출수일수간에 유의적상관을 인정할 수 없었고, 각도에서의 12개년간의 결과에 의하면 파종후 70일간의 적산온도와 출수일수간에 품종에 따라서는 유의적인 상관이 있는 것과 없는 것이 있으며, 지역저긴 차이는 인정할 수 없었다. 등은 조파의 경우에 높은 수량을 보이는 품종들이었다. 4. 품종별 수량이 파종기에 따라서 변동하는 경향을 보면 Table 4와 같이 대체로 조생종에 있어서는 파종기 연장에 따라 수량 감소의 정도가 낮고 도리어 조파보다 만파의 경우에 좋은 성적을 나타 내었으나 중생종, 만생종일수록 파종기 연장에 의한 수량 감소의 정도가 높았다. 옥면과 같은 극만생종 품종은 조반의 경우라도 상해 등으로 본실험지의 기후조건 하에서는 경제적 재배가 곤란하다고 믿는다. 따라서 조생종에 있어서는 5월 이후의 만파의 경우에, 중, 만생종에 있어서는 4월보다 도리어 5월 파종의 경우에 좋은 성적을 나타내는 경향이 있으나 품종별 파종 최적기 등의 결정문제는 앞으로 해결되어야 할 한 과제가 될 수 있을 것이라 하겠다.의 일수가 길면 신고비가 높았다. 있다. 인텔리전스(intelligence)에 따라 분류했을 경우, 모던, 엘레강스, 클래식, 소피스티케이트 등은 엘리트적 성향으로 캐주얼, 내추럴은 대중적 성향으로 분류된다. cluster에서 구현하였다. 그 결과 특정 노드의 성능이 다른 것에 비해 현저하게 떨어질 때 전체적인 알고리즘의 수렴 속도가 떨어지는 것을 상당히 완화할 수 있음이 밝혀졌다., 2001).의 특징이라 할 수 있겠다. 대한 자부심과 국제 사회에서 차별화 할 수 있는 한국 복식 디자인에 독창성과 창조성을 표현하는 중요한 영역임을 인식할 수 있었다.와 보호인자를 재확인할 필요가 있다고 보며 본 연구의 결과는 지역민의 대장직장암 예방을 위한 영양교육 자료로서 활용될 수 있다고 본다. 관여도에 영향을

• 국토계획
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• 제54권2호
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• pp.54-66
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• 2019

This study analyzed whether a subway accessibility impact on house price is constant since its operation over time or not. The study was approached specifically to answer two research questions. One is "Are there significant temporal variations in the relationship between subway accessibility and housing price transacted after its opening?" The other one is "How the pattern of its temporal variation in housing price is formed as a function of the distance from the nearest station?" The study area is the subway station areas in the Daejeon metropolitan city, South Korea. Its first subway line has started to be opened in 2006 with 12 stations and then opened its additional 10 stations in 2007. It can be more appropriate to observe its impacts of subway accessibility on housing price because it has only one transit line with more than 10-year reaction term to its operation. The study employed alternative models to estimate yearly variation of subway accessibility on house price for the station areas with 500-meter and 1-kilometer radius respectively. While the study originally considered both a hedonic price model with interaction terms of its access distance to yearly transacted housing and a time-variant random coefficient model, the former model was finally selected because it is better fitted. Based on our analysis results, the reaction of house price to its transit line had significant temporal variation over time after opening. In addition, the pattern in its variation from our analysis results indicates that its capitalization impact on house price is over-estimated in its first several years after the opening. In addition, its positive capitalization impact is more effective in the 1000-meter station area than in the 500-meter one.

• Journal of Ecology and Environment
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• 제32권2호
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• pp.103-107
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• 2009

We investigated colonization and extinction patterns in a meta population of the gold-spotted pond frog (Rana planeyi ehoseniea) near the Korea National University of Education, Chungbuk, Korea, by surveying the frogs in the nine occupied habitat patches in the study area four times per breeding season for three years (2006$\sim$2008) and recording whether the patches were occupied by frogs as well as how many frogs were calling in the patches. We then developed five a priori year-specific models using the Akaike Information Criterion (AIC). The models predicted that: 1) probabilities of colonization and local extinction of the frogs were better explained by year-dependent models than by constant models, 2) there are high local extinction and low colonization probabilities, 3) approximately 31% number of patches will be occupied at equilibrium, and 4) that considerable variation in occupation rate should occur over a 30-year period, due to demographic stochasticity (in our model, the occupation rate ranged from 0.222 to 0.889). Our results suggest that colonization is important in this metapopulation system, which is governed by mainly stochastic components, and that more constructive conservation effects are needed to increase local colonization rates.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.56-60
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• 1999

Production and reproduction data of 47 Nili-Ravi buffaloes (162 records) were analyzed with regression techniques. Average lactation milk yield was $2,020.04{\pm}44.59$ liters, lactation length $277.42{\pm}5.70$ d and calving interval $467.10{\pm}11.58$ d. The ranges for these parameters respectively were : 609-3591 lit, 122-614 d and 228-982 d. Year of calving and lactation length had significant effect on total milk yield (p < 0.01), whereas other factors such as month of calving, lactation number and calving interval had no effect on total lactation milk yield. Year of calving had influenced significantly other traits (p < .01) such as calving interval and lactations completed. This indicated considerable environment role in buffalo productivity. Effect of month of calving on total lactation milk yield and other traits was however, found to be non-significant. Nili-Ravi buffaloes produced maximum milk during their first three lactations as compared to subsequent lactations. Regression model explained 40 percent variation in total lactation milk yield due to factors analyzed : animal (dam), year and month of calving lactation length and calving interval.

• Asian Journal of Atmospheric Environment
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• 제2권1호
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• pp.47-53
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• 2008

In this study, we analyzed how ozone pollution could be differently measured and how these different measures varied year to year and across the ten most populated cities in the United States, from 1980 to 2000. Although peak values of ozone concentration have been significantly reduced in most polluted U.S. cities for the last 20 years, the annual average values of ozone concentration have not been lowered as much as peak values. Ozone concentration data for each city shows a unique pattern of distribution, central tendency, and also there is a wide variation among different ozone measures. Two different cities with the same annual mean concentration of ozone can experience very different distributions of ozone concentration within a year. Ozone measures also show a wide margin of variability as they are estimated from different ozone monitoring sites within each city. Ozone pollution statistics can be largely varied depending on the choice of measures, monitoring sites, and averaging time period. EPA's new ozone standard of 0.08 ppm averaged over an eight-hour appears to be more stringent than the current maximum ozone standard of 0.12 ppm averaged over one hour.

• 한국농공학회논문집
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• 제54권4호
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• pp.115-125
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• 2012

The comparison between the spatial and temporal variability of aridity index, precipitation effectiveness and runoff during El-Nino and La-Nina periods and that of the normal period was conducted to evaluate the regional impacts of El-Nino, La-Nina in hydrologic variables. Aridity index and precipitation effectiveness were estimated using 59 nationwide weather stations data and runoff data of WAMIS were used. The ratio of the difference between El-Nino, La-Nina year value and that of normal year was analyzed. Temporal variation demonstrated that aridity index, precipitation effectiveness and run-off discharge increase in March, April, August, November, December and decrease in February, June, September, October according to El-Nino effect. Aridity index, precipitation effectiveness and run-off discharge increase in March, May, September and decrease in June, August, November, December according to La-Nina effect. The spatial variation of those variables analyzed for different basins showed that impacts in the Han river basin relatively higher than that of other basins.

• 한국해양학회지
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• 제5권1호
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• pp.6-13
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• 1970

Ten days and monthly mean temperatures were analysed daily data observed during July, 1916 to March, 1970 statistically. Periodic characters were calculated by Δn, new method of approximate solution of Schuster Method. According to ten days mean temperatures, annual variation function is F($\theta_d$)=16.29-5.27 cos $\theta_d$+0.75 cos2 $\theta_d$-3.14 sin $\theta_d$+1.16 sin2 $\theta_d$-0.63 sin $\3{theta}_d$, where $\theta_d$=$-\frac{\pi}{18}$(d-3), d is the order of ten days period, 1 to 36. Annual mean water temperature is 16.3$^{\circ}C$, minimum in the last ten days of February 10.9$^{\circ}C$, maximum in the last ten days of August 24.5$^{\circ}C$. Periodic character of secular variation shows 11 year and its curve is F($\theta_y$)=16.29+0.53 cos $\theta_y$ -0.16cos $2{\theta}_y$+0.10 cos$3{\theta}_y$-0.10 sin $\theta_y$, where $\theta_y$=2$-\frac{2\pi}{11}$(y-1920), y is calendar year. And the relation between air temperature x and water temprature y is following. y=9.67 1.035$\^x$

• 한국수학교육학회지시리즈D:수학교육연구
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• 제14권4호
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• pp.361-380
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• 2010

Some 400 Secondary One (i.e. seventh-grade) students from 10 schools were provided with non-routine mathematical problems in their normal mathematics classes as exercises for one academic year. Their attitudes toward mathematics, their conceptions of mathematics and their problem-solving performance were measured both in the beginning and at the end of the year. Hierarchical regression analyses revealed that the introduction of an appropriate dose of non-routine problems would generate some effects on the students' conceptions of mathematics. A medium dose of non-routine problems (as reported by the teachers) would result in a change of the students' conception of mathematics to perceiving mathematics as less of "a subject of calculables." On the other hand, a high dose would lead students to perceive mathematics as more useful and more as a discipline involving thinking. However, with a low dose of non-routine problems, students found mathematics more "friendly" (free from fear). It is therefore proposed that the use of non-routine mathematical problems to an appropriate extent can induce changes in students' "lived space" of mathematics learning and broaden their conceptions of mathematics and mathematics learning.

• 한국치위생학회지
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• 제14권3호
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• pp.425-430
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• 2014

Objectives : The purpose of this study is to investigate the correlation between amalgam restorations and urinary mercury levels in children for 1 year. Amalgam restoration has been widely used for over 200 years. But released mercury from amalgam can increase the concentration of mercury in the body. Methods : The subjects were 463 elementary school children. Oral examination, urine sampling, and questionnaire survey were performed at baseline and after 1 year. Results : Amalgam restoration increased the urinary mercury level to $0.55{\pm}0.13{\mu}g/g$ creatinine. In the regression analysis, variation of urinary mercury excretion were positively associated with amalgam surfaces and fish consumption. Conclusions : Small amount of mercury release from amalgam restoration was closely associated with increasing urinary mercury level.

• The Korean Journal of Ecology
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• 제14권3호
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• pp.305-316
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• 1991

Growth hadit and demograph in a mature population of polygonatum and polygonatum humile in kanghwa island were studied for two growing seasons. Shoots of two species emerged early spring from the growing apices of the underdground rhizomes which had persisted for up to 1~5 year.after flowering, the ramets produced two rhizome buds at the shoot base. Bacause of the apical dominance in the rhizome system, a new rhizome was developed from only one bud, an actual bud,and the other latent buds were suppressed sothat remained dormant. The latent dud produced a new rhizome only when the actual dud was severed by the herbivores or by the physical obstacles. Therefore, the ramet number is not increased by the new rhizome from the latent bud. however, new ramets dould sometimes grow from latent buds which had been produced more than a year ago. Production of these ramets was main means increasing the ramet numbew and widening the potential zone of exploitation. Changes in size class of each ramet were noyiceable after a tear in small size-classes. Small ramets replaced themselves with larger-sized ramet, while large ramets with similar-sized or smallar-sized ramets. ramet numbers were average 0.82and 1.14 times of those fromthe previous year inp. involucratum and p. humile, though there was between-site variation. Almost all the ramets in the quadrats were alive during the growing season. when the entire rhizome systems were excavater next spring, there were many rhizomesegments without shoots, especially in p. involucratum. therefore, the drcrease of ramet number in p. involucratum in probably due to the climatic factors of winter.