• Title/Summary/Keyword: Seasonal effects

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Evaluation of Slope Condition using Principal Component Analysis (주성분분석법을 이용한 사면 상태 평가)

  • Jung, Soo-Jung;Kim, Tae-Hyung;Kang, Ki-Min;Lee, Young-Jun
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.416-422
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    • 2010
  • Estimating condition of geotechnical structures are difficult because of nonlinear time dependency and seasonal effects. Measuring data of structure failure is highly variable in time and space, and a unique approach cannot be defined to model structure movements. Characteristics of movements are obtained by using a statistical method called Principal Component Analysis(PCA). The PCA is a non-parametric method to separate unknown, statistically uncorrelated source processes from observed mixed processes. Instead, since the "best" mathematical relationship is estimated for given data sets of the input and output measured from target systems. As a consequence, this method is advantageous in modeling systems whose geomechanical properties are unknown or difficult to be measured.

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Seasonal Variation of Heterotrophic Activity in the Estuary of Naktong River over Half Tidal Cycle and Salinity Effect (낙동강 하구의 조석변화에 따른 Heterotrophic Activity의 계절적 변화와 염분의 영향)

  • 안태영;박중찬;하영칠
    • Korean Journal of Microbiology
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    • v.29 no.5
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    • pp.339-343
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    • 1991
  • Heterotrophic activity, total bacteria and salinity were determined seasonally in the estuary of Naktong River over half tidal cycle. Heterotrophic activity was determined by the uptake of [U- $^{14}$ C]glucose. Heterotrophic activity fluctuated with the tides and was decreased as salinity increased. Teh great activity occurred near low ebb tide at all seasons except summer. The main environmental factor affecting hetreotrophic activity was the salinity rather than water temperature in the estuary of Naktong River. In order to estimate the effect of salt, salt was added to estuarine water. Vmax for glucose of salt-added water was 17% and 77% of original estuarine water at station 1 and 2 respectively and slight increase was observed at station 3. Respiration rate and Kt+Sn for glucose of salt-added sample increased at all 3 stations. The increase of the Kt value implies the reduced affinity of bacterial population for glucose. The effects of salinity on the heterotrophic activity were more extensive in the upper region of estuary than at the mouth.

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Effects of Air Pollution on Precipitation and Living Organisms in Seoul Area (서울 地域의 大氣汚染이 降水와 생물에 미치는 영향 1.地域別 降水의 酸性化에 관하여)

  • Chang, Nam-Kee;Lee, Yun-Sang;Shin, Eun-Yong
    • The Korean Journal of Ecology
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    • v.13 no.2
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    • pp.131-142
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    • 1990
  • From July 1, 1985 to June 30, pH values of precipitation in Seoul area were average 5.1 and acid rain which was lower than pH 5.5 showed a frequence of 70.7%. Seasonal changes appeared in pH values of annual precipitation in Seoul. The pH patterns of spring and autumn were generally less acid than that of summer and winter, and snowfall pH was lower than rainfall. The beginning rainfall in Seoul was neutral because of alkali dust in the atmosphere. As times went on, rainfall pH was gradually low and after 1 to 2 hours, showed a steady state. On the surface soil precipitation was neutralized by soil buffering capacity.

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Characterization of landfarming for bioremediation of petroleum-contaminated soil in Korea (유류오염토양의 생물학적 복원을 위한 국내 토양경작기술의 적용 특성)

  • Lee Kwang-Pyo;Lee Cheol-Hyo
    • 한국생물공학회:학술대회논문집
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    • 2004.07a
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    • pp.107-125
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    • 2004
  • A bioremediation of petroleum-contaminated soil in Korea was evaluated for the optimization of enhanced biodegradation and the minimization of effects of seasonal variations, The short-term bioremediation in combination of biopile pretreatment and landfarming was performed by lowering contaminated levels and overcoming the inhibiting factors in the rainy and winter seasons. A microbial density was maintained with indigenous microbial addition for bioaugmentation and with fertilizers for biostimulation. A lesser volatile and biodegradable fraction due to their abiotic removals following the biopile pretreatment was effectively removed by the laterally applied landfarming. The optimal temperature in greenhouse was maintained by buffering of the soil temperature even with slight decreases in removal rates during the winter and extensive leaching of nutrients and contaminants was restricted with adjusting the water contents during the Korean rainy season. Although the tilling process was effective for biodegradation with aeration only, the simultaneous treatment due to apparent mixing of nutrients and microbes more favorably degraded the petroleum than the sequential treatment.

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A seasonal growth curve estimation for continuous spawning fishes (연속 산란 어류의 온도함수 성장곡선 추정)

  • Choi, Il-Su
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.5
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    • pp.903-910
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    • 2011
  • The von Bertalanffy growth function (VBGF) is the result of the antagonistic effects of anabolism and cataboliem. However VGBF has limitations for describing the growth of continuous spawning fishes. In the present work, a new equation is proposed where the growth parameter Kis substituted by a function related to the sea surface temperature of spawning period. Examples for natural population of Pacific Anchovy are presented.

Existing concrete dams: loads definition and finite element models validation

  • Colombo, Martina;Domaneschi, Marco;Ghisi, Aldo
    • Structural Monitoring and Maintenance
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    • v.3 no.2
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    • pp.129-144
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    • 2016
  • We present a methodology to validate with monitoring data finite element models of existing concrete dams: numerical analyses are performed to assess the structural response under the effects of seasonal loading conditions, represented by hydrostatic pressure on the upstream-downstream dam surfaces and thermal variations as recorded by a thermometers network. We show that the stiffness effect of the rock foundation and the surface degradation of concrete due to aging are crucial aspects to be accounted for a correct interpretation of the real behavior. This work summarizes some general procedures developed by this research group at Politecnico di Milano on traditional static monitoring systems and two significant case studies: a buttress gravity and an arch-gravity dam.

Effect of Parity and Season of Calving on Service Period in Nili Ravi Buffalo in Pakistan

  • Naqvi, A.N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.3
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    • pp.287-291
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    • 2000
  • The study was based on 1921 service period records of Nili Ravi buffaloes maintained at six dairy farms in Pakistan during the period 1978 to 1994. The mean service period was $237.57{\pm}4.5$ days in the over all data. The highest mean service period ($393.59{\pm}16.18$ days) was at MDF Rawalpindi and the lowest ($199.15{\pm}14.35$ days) was at MDF Peshawar. The difference was significant p<0.001. Late maturing buffaloes showed significantly longer service period as compared to early maturing buffaloes. Parity and seasonal effects on Service Period were studied. There was an overall trend of reduction in the length of service period with the increase in parity. The mean ($287.54{\pm}6.89$ days) service period was (highest) in parity number one and lowest in parity number eight ($107.95{\pm}19.72$ days). The difference was highly significant. In overall data significantly lower service periods were seen in buffaloes calving in spring+winter as compared to summer+fall.

Identification and Analysis of External Event Combinations for Hanhikivi 1 PRA

  • Helander, Juho
    • Nuclear Engineering and Technology
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    • v.49 no.2
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    • pp.380-386
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    • 2017
  • Fennovoima's nuclear power plant, Hanhikivi 1, $Pyh{\ddot{a}}joki$, Finland, is currently in design phase, and its construction is scheduled to begin in 2018 and electricity production in 2024. The objective of this paper is to produce a preliminary list of safety-significant external event combinations including preliminary probability estimates, to be used in the probabilistic risk assessment of Hanhikivi 1 plant. Starting from the list of relevant single events, the relevant event combinations are identified based on seasonal variation, preconditions related to different events, and dependencies (fundamental and cascade type) between events. Using this method yields 30 relevant event combinations of two events for the Hanhikivi site. The preliminary probability of each combination is evaluated, and event combinations with extremely low probability are excluded from further analysis. Event combinations of three or more events are identified by adding possible events to the remaining combinations of two events. Finally, 10 relevant combinations of two events and three relevant combinations of three events remain. The results shall be considered preliminary and will be updated after evaluating more detailed effects of different events on plant safety.

Theoretical Study for the Characteristics of Melatonin (멜라토닌의 특성에 대한 이론적 연구)

  • Kim, Dong-Yeub;Jung, Maeng-Joon;Lee, Chul-Jae
    • Journal of the Korean Society of Industry Convergence
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    • v.15 no.2
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    • pp.59-63
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    • 2012
  • Melatonin has been studied as a potential treatment of cancer, immune disorders, cardiovascular diseases, depression, seasonal affective disorder (SAD), circadian rhythm sleep disorders, sexual dysfunction and some forms of insomnia. Prolonged release melatonin has shown good results in treating insomnia in older adults. It may ameliorate circadian misalignment and SAD. Basic research indicates that melatonin may play a significant role in modulating the effects of drugs of abuse such as cocaine. A 2004 review found that melatonin significantly increased total sleep time in people suffering from sleep restriction. Therefore, in this study, in order to explain characteristics of melatonin, total energy, net charge, vibrational mode of melatonin are calculated by PM3 methods of HyperCam 6.0.

A Study on the Effects of Well-being Trend on Menu Selection Behavior (웰빙 트랜드가 메뉴 선택에 미치는 영향에 관한 연구)

  • Park, Geun-Han;Park, Heon-Jin;Jung, Jin-Woo
    • Culinary science and hospitality research
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    • v.14 no.3
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    • pp.45-57
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    • 2008
  • The purpose of this study is to initiate a systematic approach to maximize profits through continuous development of menu and build a strong image of Western restaurants located inside hotels by identifying their guests' knowledge and concern and menu selection behavior in well being trend. Findings from the analysis are as follows. First, among the Western menu selection behavior, organic grain and seafood, seasonal event menu, less spicy and more natural cooking methods are favored as the most important consideration. Second, customers' knowledge and concern in well being trend and menu selection behavior were found to be statistically significant. Third, customers' awareness in health and obesity were found to be statistically significant to the concern in well being trend. Fourth, demographical characteristics of customers such as gender, marital status, age, income level and education were tested for their relationships with knowledge and concern in well being trend.

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