• 제목/요약/키워드: Occurrence intensity

검색결과 326건 처리시간 0.021초

오호츠크해고기압의 출현일과 강도의 변동에 관한 연구 -한반도에 영향을 미친 날을 중심으로- (A Study on the Frequency and Intensity Variations of Okhotsk High: Focused on the Korean Peninsula)

  • 조리나;이승호
    • 대한지리학회지
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    • 제46권1호
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    • pp.36-49
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    • 2011
  • 본 연구에서는 오호츠크해고기압이 한반도에 영향을 미치는 날과 강도의 변화를 규명하고자 하였다. 지상 일기도와 기상자료, 재분석자료 등을 분석하여 다음과 같은 결과를 얻었다. 4월의 주변 육지기온이 높은 해일수록 오호츠크해고기압의 첫 출현일이 일러지는 경향이다. 최근 오호츠크해고기압의 출현일수는 감소하였으며, 그 강도는 6월 해수면온도와 주변 육지기온의 차이가 클수록 강해지는 경향이다 4 5월, 6월, 7월의 오호츠크해고기압 출현일수는 주변 육지기온이 상승할수록 증가하며, 해수면온도와 주변 육지 기온의 차이가 커질수록 강도가 강해진다. 오호츠크해고기압의 첫 출현일이 일러짐에 따라 4월과 5월의 오호츠크해고기압 출현일수는 증가하고 강도는 약해질 수 있다. 그러나 6월에는 반대의 경향이 나타날 수 있다.

접착이음의 강도평가에 대한 해석 (Analysis for Strength Estimation of Adhesive Joints)

  • 박성완;이장규
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 추계학술대회 논문집
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    • pp.98-107
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    • 2004
  • The objectives of this research are to establish the criteria of peel occurrence considering the shape of bond terminus and to compare the strength properties of some adhesive joints. The criteria of feel occurrence at the bond terminus was suggested. Peel loads of some adhesive joint(butt joint, T -shape specimen, single lap joint) were determined from tensile tests. Principal stress distributions of these joints were determined from finite element method analysis. Then, peel occurrence was estimated with intensity of stress singularity ' $K_{prin.}$' when the terminus shape was square, with average principal stress when the terminus shape was rounded. The conclusions are summarized as follows; (1) In the non-filleted model(e.g., butt joint, T-shape specimen), principal stress shows singularity at the bond terminus, intensity of stress(principal stress) singularity ' $K_{prin.}$&apso; can use as the criteria of peel occurrence at the bond terminus. (2) In the filleted model(e.g., single lap joint), principal stress doesn't show singularity at the bond terminus. Average principal stress can use as the criteria of peel occurrence at the bond terminus.'t show singularity at the bond terminus. Average principal stress can use as the criteria of peel occurrence at the bond terminus.

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Monitoring of Non-point Source Pollutants Generated by a Flower Farm

  • Choi, Byoungwoo;Kang, Meea
    • 지질공학
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    • 제24권4호
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    • pp.463-471
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    • 2014
  • This paper considers the effect of rainfall on non-point source (NPS) pollutant loads. The impact of runoff on the occurrence of NPS pollutants was found to be influenced by rainfall amount, rainfall intensity, and the number of antecedent dry days (ADD), both independently and in combination. The close correlation ($R^2$ = 0.9920) between rainfall and runoff amounts was demonstrated at the study site (a flower farm) over the period between January 2011 and December 2013. The relationships among pollutant levels, runoff, and rainfall was not satisfactory results except for the Biochemical Oxygen Demand ($BOD_5$). The correlation coefficients between $BOD_5$, and both runoff and rainfall, were greater than 0.92. However, the relationships of other pollutants, such as Suspended Solid (SS), Chemical Oxygen Demand ($COD_{Mn}$), Total Nitrogen (TN), and Total Phosphorus (TP), with runoff and rainfall had correlation coefficients of less than 0.70. The roles of rainfall was different from rainfall categories on the occurrence of runoff. Instantaneous rainfall intensity was a principle factor on the occurrence of runoff following light rainfall events (total ${\leq}30mm$). For rainfall of intermediate intensity (total precipitation 31-50 mm), the combined effect of both average rainfall intensity and ADD was found to influence runoff generation. We conclude that the control of NPS pollutants with the reflection of the climate change that makes the remarkable effect of amounts and forms on the rainfall and runoff.

인공강우장치를 이용한 산불발생지의 토양침식 특성에 관한 연구 (Characteristics of Soil Erosion on the Forest Fired Sites by Using Rainfall Simulator)

  • 이헌호;주재덕
    • 한국산림과학회지
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    • 제95권6호
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    • pp.649-656
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    • 2006
  • 인공강우발생장치를 이용하여 4년간 대구 동구지역에 발생한 산불발생지를 대상으로 산불발생지사면의 토양침식량을 계량화하기 위하여 산불발생 후 경과년수에 띠라 각 지역에 대한 강우강도 및 경사별로 토양침식량을 관측하여 산불발생지의 토양침식 특성을 구명하고, 또한 토양침식량과 강우강도, 경사, 경과년수와의 관계를 분석한 결과는 다음과 같다. 1. 산불발생연도별 토양침식량은 강우강도가 30 mm/hr씩 증가함에 따라서 1.9~5.7배 증가하였고, 경사가 $10^{\circ}$씩 증가함에 따라서는 1.4~14.2배 증가하였다. 2. 산불발생당년에는 강우강도 80 mm/hr, 경사 $30^{\circ}$에 대해 초기 강우 10분 동안 토양침식이 많이 발생하였으며, 시간이 경과할수록 점차 그 양이 감소하는 경향을 보였고, 산불발생 후 2년 뒤부터는 강우강도 및 경사별로 경과시간에 따른 토양침식량은 거의 일정하였다. 3. 산불발생 후 경과년수에 따라 강우강도 및 경사별 토양침식량은 산불발생 3년 후의 경우 발생당년에 비해 28.9%~94.1%로 감소하였고, 산불발생당년에는 강우강도 및 경사별로 토양침식량이 많았으며, 산불발생 후 2년 뒤부터 점차 토양침식량의 감소추세가 둔화되었다. 4. 산불발생지사면에서의 토양침식량에 대해 각 인자간의 영향성을 분석한 결과, 강우강도, 경사, 경과년수의 각각의 주효과와 강우강도${\times}$경사, 강우강도${\times}$경과년수의 상호작용 효과에 대해서는 차이를 보였고, 경사${\times}$경과년수, 강우강도${\times}$경사${\times}$경과년수의 상호작용 효과에 대해서는 차이가 없었다. 토양침식량에 영향을 미치는 인자의 영향도는 강우강도가 가장 큰 영향을 미치고 다음이 경사, 경과년수의 순이었다. 5. 토양침식량과 이에 영향을 미치는 인자들과의 상관관계에 있어서, 강우강도, 경사간에는 1%수준에서 유의적인 정(+)의 상관관계가 있었고, 경과년수는 1%수준에서 유의적인 부(-)의 상관관계가 나타났다. 6. 토양침식량과 이에 영향을 미치는 인자들과의 회귀분석 결과, 산불발생지사면에서 토양침식량을 설명하는데 유의한 인자는 강우강도, 경사, 경과년수이었다. 7. 강우강도, 경사, 경과년수를 이용하여 다음과 같은 토양침식량 추정식을 산출하였다. S.E = 0.092R.I + 0.211D.S - 0.942E.Y(S.E : 토양침식량, R.I: 강우강도, D.S: 경사, E.Y: 경과년수)

전기점화기관에서 마이크로폰 센서를 이용한 노킹 측정 및 분석 (Measurement and Analysis of Knock Using a Microphone Sensor in a S.I. Engine)

  • 황승환;이종화;임진수
    • 한국자동차공학회논문집
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    • 제5권3호
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    • pp.202-208
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    • 1997
  • The knocking is one of major parameters to improve engine performance in a spark ignition engine. Many researches have been carried out to identify them using cylinder pressure, vibration signal and so on. In the present study, measurement and analysis was conducted to set up the criteria of knock occurrence by using microphone signal. Cylinder pressure was measured for the reference signal of knocking. It has been observed that resonance frequencies of pressure wave are nearly independent of engine operating conditions such as engine speed, air fuel ratio, load and octane number of fuel within to limited experimental conditions. SDBP(sum of different band-pass data) method using resonance frequency of knock was proposed for estimating knock intensity. SDBP method is superior to identify knock occurrence and its intensity in case of sound pressure measurement.

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2011년 집중호우로 인한 산사태 발생특성 분석 (Characteristics of Heavy Rainfall for Landslide-triggering in 2011)

  • 김석우;전근우;김진학;김민식;김민석
    • 한국산림과학회지
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    • 제101권1호
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    • pp.28-35
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    • 2012
  • 강우는 산사태를 야기하는 주된 요인으로 최근 우리나라에서 대부분의 산사태는 단기간의 집중호우로 인해 발생하고 있으나, 강우특성과 산사태 발생간의 관계는 아직 명확히 규명되지 못하고 있는 실정이다. 이 논문에서는 2011년 6월 7월에 남부지방과 중부지방에서 집중호우로 야기된 18개의 산사태를 대상으로 연속강우 개시 이후의 누적강우량(mm)과 강우강도(mm/hr) 및 선행강우량(mm)을 해석하여 산사태 발생과의 관계를 분석하였다. 그 결과, 산사태는 모두 연속강우 개시 이후 1~3일간의 집중호우에 의해 강우강도가 30 mm/hr이상, 혹은 누적강우량이 200 mm이상인 경우에 발생한 것으로 나타났다. 이는 산림청의 산사태 경보발령 기준을 상회하는 범위에서 발생한 것으로 나타났으며, 경상남도에서 보고된 산사태 발생영역과도 일치하였다. 또한, 강우개시 이후 산사태 발생까지의 소요시간(T)은 평균 강우강도(ARI)가 증가할수록 점차 단축되는 것으로 나타났으며, 이들 사이의 관계는 지수함수식 "T = $94.569{\cdot}exp$($-0.068{\cdot}ARI$)($R^2$=0.64, p<0.001)"로 도출되었다. 이러한 결과는 산림청의 산사태 주의보 경보발령 기준에 있어 중요한 근거가 될 수 있으며, 토사재해에 대한 경계피난체계 등의 비구조물 대책의 수립에도 기초자료를 제공할 수 있을 것으로 기대된다.

스파크 점화 기관의 실린더 블록 진동 신호를 이용한 노킹 제어 (Knock Control Using Cylinder Block Vibration Signals in a Spark-Ignition Engine)

  • 함윤영;전광민
    • 한국자동차공학회논문집
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    • 제5권1호
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    • pp.186-194
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    • 1997
  • The objective of this study is to develope knock control algorithms which can increase engine power without causing frequent knock occurrence. A four cylinder spark-ignition engine is used for the experiments to develop knock control algorithms which use block vibration signals. Knock occurrence is detected accurately by using knock threshold values which consider the difference of transmission path of each cylinder. Spark timing is controlled both simultaneously and individually. With the simultaneous control, torque gain is achieved by retarding the spark timing on knock occurrence in propotion to the knock intensity. The individual knock control algorithm results in higher torque gain than the simultaneous knock control algorithm. The knock occurrence frequency of the individual knock control algorithm is about twice the value of the simultaneous knock control algorithm results. Both control algorithms give similar torque gain of about 3% when they are optimized.

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A Finger Dermatoglyphics of the New Zealand-Samoans

  • Cho, Ching
    • Animal cells and systems
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    • 제2권4호
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    • pp.507-511
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    • 1998
  • Fingerprints of 100 New Zealand-Samoan males and 93 females have been analyzed. Whorls are more numerous in fingerprint females (65.6%) than in males (55.6%). The index of pattern intensity displays a higher value in females (16.49) than in males (15.48). The bimanual differences both in males and females are not statistically significant for the occurrence of patterns on the digits of the right and left hands. Also the difference between both sexes for the occurrence of patterns is not statistically significant. Incidences of actual symmetry on homologous digits represented 78.2% in males and 85.8% in females. The mean total ridge counts showed $175.7{\pm}54.6$ ($M{\pm}SD$) in males and $171.6\{pm}49.8$ ($M{\pm}SD$) in females, respectively. Conclusively, this study shows that the New Zealand-Samoans are closely related to the Mongoloids in quantitative dermatoglyphics.

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Finger Dermatoglyphics of Australian Aborigines in the Northern Territory of Australia

  • Cho, Ching
    • Animal cells and systems
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    • 제4권1호
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    • pp.91-94
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    • 2000
  • Fingerprints of 114 Australian Aboriginal males and 90 females have been analyzed. Whorls are more frequent in males (56.7%) than in females (51.2%) and loops are less frequent in males (42.6%) than in females (47.0%). The index of pattern intensity displays a higher value in males (15.60) than in females (14.94). The bimanual differences both in males and females ave not statistically significant for the occurrence of patterns on the digits of the right and left hands. Also the difference between both sexes for the occurrence of patterns is not statistically significant. Incidences of actual symmetry on homologous digits represented 74.0% in males and 77.3% in females. The mean total ridge counts showed 156.65 $\pm$43.32 (M$\pmSD) in males and 148.6943.64 (M$\pmSD) in females, respectively. Conclusively, this study represents that the Australian Aborigines conform closely to the Polynesians in finger dermatoglyphics.

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A comparative study of ectoparasites occurrence between grass carp and silver carp in guilan province culture ponds, Iran

  • Asgharnia, Mehrdad;Ghasemi, Mohaddes
    • 한국어병학회지
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    • 제34권2호
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    • pp.169-176
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    • 2021
  • Parasitic infection is among the most common problems for carp cultivation. They are also important for the principal entrance of other hazardous infections as well. This study was carried out for determining of parasitic fauna of two major carp known as silver and grass carp with the comparison of prevalence value and intensity rate of parasites among them, alongside the relationship between the biometric characteristics and host sex with the infection level. For this purpose, a total of 94 fish samples were caught randomly using a fishing net, from Guilan ponds during spring and summer of the year 2018 and transported alive to the laboratory. Upon arriving, the biometric characteristics and genus of each carp were measured individually. Specimens were then acquired from the skin, gills, and eyes of the carp and examined according to standard parasitology methods. Recovered parasites were observed under a light microscope and then fixed for identification. As the result, the occurrence and intensity in the higher length group were comparatively greater than the lower one. Also, the prevalence and intensity of total parasites in male carp were higher than in females. In this research, Dactylogyrus hypophthalmichthys and Dactylogyrus aristhichtys were observed in silver carp and Dactylogyrus lamellatus was detected in grass carp. In the paper below, we found that the host specificity varies in different species of Dactylogyrus isolated from grass carp and silver carp.