• Title/Summary/Keyword: Trend Test

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Estimations and Long-term Trend of Sea-to-air Dimethyl Sulfide (DMS) Flux using Satellite Observation Data (인공위성 관측 자료를 이용한 해양-대기 DMS flux 추정 및 장기 추세 분석)

  • Choi, Yu-Na;Song, Sang-Keun;Han, Seung-Beom;Son, Young-Baek;Park, Yeon-Hee
    • Ocean and Polar Research
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    • v.39 no.3
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    • pp.181-194
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    • 2017
  • The long-term linear trend of global sea-to-air dimethyl sulfide (DMS) flux was analyzed over a 16-year time span (2000~2015), based on satellite observation data. The emission rates of DMS (i.e. DMS flux) in the global ocean were estimated from sea surface DMS concentrations, which were constructed with chlorophyll a (Chl-a) concentrations and mixed layer depths (MLD), and transfer velocity from sea to air, which was parameterized with sea surface wind (SSW) and sea surface temperature (SST). In general, the DMS flux in the global ocean exhibited a gradual decreasing pattern from 2000 (a total of 12.1 Tg/yr) to 2015 (10.7 Tg/yr). For the latitude band ($10^{\circ}$ interval between $0^{\circ}$ and $60^{\circ}$), the DMS flux at the low latitude of the Northern (NH) and Southern hemisphere (SH) was significantly higher than that at the middle latitude. The seasonal mean DMS flux was highest in winter followed by in summer in both hemispheres. From the long-term analysis with the Mann-Kendall (MK) statistical test, a clear downward trend of DMS flux was predicted to be broad over the global ocean during the study period (NH: $-0.001{\sim}-0.036{\mu}mol/m^2/day\;per\;year$, SH: $-0.011{\sim}-0.051{\mu}mol/m^2/day\;per\;year$). These trend values were statistically significant (p < 0.05) for most of the latitude bands. The magnitude of the downward trend of DMS flux at the low latitude in the NH was somewhat higher than that at the middle latitude during most seasons, and vice versa for the SH. The spatio-temporal characteristics of DMS flux and its long-term trend were likely to be primarily affected not only by the SSW (high positive correlation of r = 0.687) but also in part by the SST (r = 0.685).

Applications of the Sediment-Transport Path Model to the Tidal Flats of Garolim Bay, West Coast of Korea

  • Shin, Dong-Hyeok;Yi, Hi-Il;Han, Sang-Joon;Oh, Jae-Kyung;Won, Joong-Sun
    • International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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    • v.23 no.1
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    • pp.39-51
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    • 1995
  • Bidirectional transport trend using the sediment-transport path model was identified in the two areas, sand ridge area and tidal mudflat in Garolim Bay, which is located in the mid-western coast of Korean Peninsular. This model exhibits the two-dimensional view of clear sediment transport trend based on data of changes in sediment statistics such as mean, sorting, and skewness, Garolim Bay was selected to test for the sediment-transport path model developed by McLaren and Bowles [1985]. Line-S, a typical tidal mudflat and representative of the Garolim Bay tidal flats, is well tested by this model, showing a clear seasonal change and coarsening-trend seaward (case C). This indicates that strong ebb currents carried relatively coarser sediments seaward with respect to high energy regime. Seasonally, this energy regime slowly decreases toward the summer in contrast with an increase of energy regime of flood tides, carrying coarser sediments landward (case C) in the summer. However, the Line-D area does not show consistent transport trend with respect to time-series. Separated and scattered events show fining trend landward (case B) in the sand ridge itself. The finining-trend (case B) either seaward and landward is not chiefly important in both the entire Line-D area and sand ridge itself. Also, the coarsening-Trend (case C) landward is not significant in the sand ridge itself. Consequently, in reality, the selection of suitable and representative locations are very important to fit with this model.

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The Analysis of Climate Change in Haiyan County

  • Yu, Wenzheng;Zhang, Hanxiaoya;Chen, Tianliang;Liu, Jing;Shen, Yanbo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.10
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    • pp.3941-3954
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    • 2020
  • In this paper, the climate change in Haiyan County in recent decades was analyzed in detail with the methods of moving average, Mann-Kendall non-parametric mutation test and wavelet analysis. According to the variation trend of meteorological factors such as temperature, relative humidity, wind speed, pan evaporation and precipitation in recent decades, the climate of Haiyan County has a tendency of drought, which is becoming more and more serious. From the results of the analysis, the sunshine hours and the air temperature in Haiyan County have an obvious upward trend. The average surface temperature has increased by 2.75 ℃ from 1976, and its largest increase occurred in the late 1970s and 1980s. At this stage, the average surface temperature increased by 1.37 ℃. The relative humidity has a decreasing trend that has decreased by 2.75%. From 1976 to the present, there are two quasi-3a cycles and one quasi-6a cycle. The precipitation and evaporation showed the opposite change trend, in which the trend of precipitation fluctuated upward, while the trend of evaporation showed a fluctuating downward tendency, which led to the serious loss of water in the feeding area. The wind direction in Haiyan County are mainly from west to east, and its wind speed has a trend of slight increase.

A Study on the Hair Colour Accompanied with Hair Fashion Feeling - Focussed on the Capital Area Women in Their Twenties - (헤어패션감각(感覺)에 따른 헤어컬러에 관(關)한 연구(硏究) - 수도권(首都圈) 20대(代) 여성(女性)을 중심(中心)으로 -)

  • An, Hyeon-Kyeong;Cho, Kyu-Hwa
    • Journal of Fashion Business
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    • v.10 no.2
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    • pp.99-116
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    • 2006
  • This study was aimed at giving help to the people intending to change their hair fashion feeling for changing their own hair colour design and also providing the guide line to the cosmetic circles for developing new hair colour design and promoting sales by statistically analyzing hair colours and the other factors(demographic characteristics, hair styling, total fashion feeling, hair style) of capital area women in their twenties based on the theoretical study on tatal fasion feeling & hair fashion feeling, and hair trend. The researching methods were composed of prior theoretical research, statistical analysis. The prior theoretical research was accomplished by analysis of literatures, magazines and internet sites about total & hair fashion feelings and hair trend. The statistical analysis used a questionnaire composed of 33 questions in 5 categories. The survey of the questionnaire had been conducted from June 15 to June 28 in 2005 on the 600 women in the capital area, investigated by a group of experts on cosmetics or clothing from academic or business society. The analysis of materials from the survey was done by SPSS program(ver. 12.0) using frequency analysis, $x^2$-test and cross tabulation analysis specified on high significant values. Based on the above results of $x^2$-test and cross tabulation analysis, categorized the characteristics of the hair fashion feeling groups, especially hair colours in the order of percentage. This study would be very helpful to the people trying to change their own hair fashion feeling and be useful to the cosmetic circles for developing new hair colour design and promoting sales by comprehending hair colour market and also be valuable to develop the analysis methodology of hair colour and hair fashion trend.

The Study for Process Capability Analysis of Software Failure Interval Time (소프트웨어 고장 간격 시간에 대한 공정능력분석에 관한 연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • Convergence Security Journal
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    • v.7 no.2
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    • pp.49-55
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    • 2007
  • Software failure time presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing. For data analysis of software reliability model, data scale tools of trend analysis are developed. The methods of trend analysis are arithmetic mean test and Laplace trend test. Trend analysis only offer information of outline content. From the subdivision of this analysis, new attemp needs the side of the quality control. In this paper, we discuss process capability analysis using process capability indexs. Because of software failure interval time is pattern of nonnegative value, instead of capability analysis of suppose to normal distribution, capability analysis of process distribution using to Box-Cox transformation is attermpted. The used software failure time data for capability analysis of process is SS3, the result of analysis listed on this chapter 4 and 5. The practical use is presented.

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A Study on the Reliability(Environmental) Test Trend in Korea Electronic Industries (국내 전자부품 중소기업의 신뢰성 시험 활용현황 및 지원방향)

  • Kang, Bo-Chul;Cho, Jai-Rip
    • Proceedings of the Korean Society for Quality Management Conference
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    • 2007.04a
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    • pp.331-333
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    • 2007
  • Product reliability is important to quality and competitiveness. Much management and engineering efforts go into evaluating reliability, assessing new designs and changes of manufacturing processes, identifying cause of failure. Major methods are based on environmental test. In this study, we analysis the environmental test data of the electrical component, unit, set. These data were gathered for 7 years.

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광미를 이용한 납 오염토양의 향상된 Electrokinetic 정화

  • 조용실;김정환;한상재;김수삼
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2002.04a
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    • pp.279-282
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    • 2002
  • In this study, mine tailing buffer zone in cathode was used to overcome precipitation of heavy metals that reducing remediation efficiency during electrokinetic remediation. Test results showed that heavy metal transportation affected by initial soil pH which was verified through traditional test and enhanced test with two type of soils. With mine tailing enhanced method 39% of extraction rate was achieved in surface soil and significant transportation trend was observed in deep soil.

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An Analysis on the Research Trends of Social Psychological Aspects of Clothing (복식사회.심리학분야의 연구경향 분석 I)

  • 이인자
    • Journal of the Korean Society of Costume
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    • v.30
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    • pp.19-40
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    • 1996
  • The purpose of this study is to make and analyse established studies of clothing pay-chology and marketing, showing the disciplin-ary trends problems and the outlook of social psychological Aspects of clothing. To achieve the purpose 621 articles have been used. -519 for master's and doctor's de-gree and 102 reported in journals -no social psychological Aspects of clothing for the past two decades(1974-1994) in Korea. All of these annual data were classified into making five years a unit. In the statistical analy-sis 'frequency' and 'percentage' were applied. To verify the degree of significance x2-test were used. 1. The trend of the study on the fields of clothing psychology consumer behavior and marketing over the period between 1974 and 1994 showed the continual trend of increase since the 1974 that the article on the field of clothing the continual trend of increase since the 1974 that the article on the field of cloth-ing psychology was first reported. 2. The domain that has the greatest pro-portion in the field of clothing psychology is concerned with the individual psychological factor and the study concerning interpersonal perception and development the measurement tool showed the tendency to continue to in-creas.

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Effect of Dietary Root Powder of Angelicae gigantis on Growth Performance, Organ Weight and Serum Components in Broiler Chicken (당귀근부 첨가사료가 육계의 생산성과 장기발육 및 혈액성장에 미치는 영향)

  • 조성구
    • Korean Journal of Poultry Science
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    • v.22 no.3
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    • pp.145-153
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    • 1995
  • The root powder of Angelicae gigantis Radix (RPAGR) is known to he beneficial for liver and blood circulation. In a 6-wk broiler feeding trial, the RPAGR was added at levels of 0, 0.2, 0.5, and 1.0%, respectively. The RPAGR was found to be palatable as birds consumed moreof the test diets than the control(0% RPAGR) diet. The BW gain of 1.0% RPAGR group was higher than the control group. The feed efficiency(F/G) was improved significantly(P<0.01) by feeding 1.0% RPAGR. The RPAGR also caused beneficial effects in various carcass characteristics, i.e., carcass weight, dressing percentage, breast muscle, and thigh meat production. There was no consistent trend in various organ weights by the addition of RPAGR. Also, no consistent trend was found in abdominal fat weight. The serum cholesterol level tended to decrease as the BW increased. No consistent trend was detected in serum triglyceride contents.

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