• Title/Summary/Keyword: Time prediction

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Analysis on Spatial Variability of Rainfall in a Small Area (소규모 지역에 대한 강우의 공간변화도 분석)

  • Kim, Jong Pil;Kim, Won;Kim, Dong-Gu;Lee, Chanjoo
    • Journal of Korea Water Resources Association
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    • v.48 no.11
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    • pp.905-913
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    • 2015
  • This study deployed six rain gauges in a small area for a dense network observing rainfall and analyzed the spatial variability of rainfall. They were arranged in a $2{\times}3$ rectangular grid with equal space of 60 m. The rainfall measurements from five gauges were analyzed during the period of 50 days because one was seriously affected by alien substance. The maximum difference in cumulative rainfall from them is approximately 38.5 mm. The correlation coefficients from hourly rainfall time series differ from each other while daily rainfall coincide. The coefficient of variation in hourly rainfall varies up to 224% and that in daily rainfall up to 91%. The results from uncertainty analysis show that with only four rain gauges areal mean rainfall cannot be estimated over 95% accuracy. For reliable flood prediction and effective water management it is required to develop a new technique for the estimation of areal rainfall.

Efficient Methods for Detecting Frame Characteristics and Objects in Video Sequences (내용기반 비디오 검색을 위한 움직임 벡터 특징 추출 알고리즘)

  • Lee, Hyun-Chang;Lee, Jae-Hyun;Jang, Ok-Bae
    • Journal of KIISE:Software and Applications
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    • v.35 no.1
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    • pp.1-11
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    • 2008
  • This paper detected the characteristics of motion vector to support efficient content -based video search of video. Traditionally, the present frame of a video was divided into blocks of equal size and BMA (block matching algorithm) was used, which predicts the motion of each block in the reference frame on the time axis. However, BMA has several restrictions and vectors obtained by BMA are sometimes different from actual motions. To solve this problem, the foil search method was applied but this method is disadvantageous in that it has to make a large volume of calculation. Thus, as an alternative, the present study extracted the Spatio-Temporal characteristics of Motion Vector Spatio-Temporal Correlations (MVSTC). As a result, we could predict motion vectors more accurately using the motion vectors of neighboring blocks. However, because there are multiple reference block vectors, such additional information should be sent to the receiving end. Thus, we need to consider how to predict the motion characteristics of each block and how to define the appropriate scope of search. Based on the proposed algorithm, we examined motion prediction techniques for motion compensation and presented results of applying the techniques.

A study on applicability of volumetric water content to predict shallow failure (표층붕괴 예측을 위한 체적함수비 적용성 연구)

  • Suk, Jae-Wook;Song, Hyo-Sung;Kang, Hyo-Sub;Kim, Ho-Jong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.737-746
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    • 2019
  • Most landslides in the country are shallow failures triggered by intense rainfall. Many researchers have revealed the possibility of predicting shallow failure through the volumetric water content (VWC). This study examined how to determine shallow failure using the gradient characteristics of the volumetric water content. For this, flume experiments were conducted using weathered granite soil. To confirm the saturation state of the surface layer under a rainfall intensity of 30 and 50mm/hr, VWC sensors were installed at depths of 10 and 20 cm on the upper, middle and lower slope. The test results showed that a shallow failure determination using VWC could be applied limitedly according to the slope degree. In addition, the effective cumulative rainfall due to the rainfall infiltration velocity is considered the main factor for the failure time. The failure prediction using the gradient of the VWC depends on the installation location and depth of the sensor. According to the experimental data, the measured value at 20 cm below the slope was most effective. Therefore, an analysis method of VWC and the method of selecting the installation location confirmed through this study can provide important data for presenting the measurement criteria using VWC in the future.

Study on the Estimation of Long Life Cycle and Reliability Tests for Epoxy Insulation Busway System (에폭시 박막 절연형 버스웨이 시스템의 장기 수명 및 신뢰성 평가에 관한 연구)

  • Jang, Dong-Uk;Park, Seong-Hee;Lee, Kang-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.9
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    • pp.261-268
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    • 2018
  • The use of electric cable was limited due to the installation time and large space as the increase of power demand and load quantity in side line. In order to solve these problems, the application of busway system which can supply the large current was increasing. But it was lack of methods of performance tests to evaluate the reliability and results of test for busway system. In this paper, we presented items to evaluate the reliability test for epoxy coated busway system with reference to IEC 61349-6. In addition, we proposed items to evaluate the reliability and long term life cycle test for the epoxy coated busway system. The combined acceleration deterioration test that reflects actual conditions of the survey as much as possible was conducted considering both thermal and electrical stresses. The deterioration condition was selected to satisfy fifty years life expectation and the insulation performance verification test of the busway system confirmed the long term life prediction. Furthermore, as test items for reliability assessment of compliance with the environment for the use of temperature, humidity and load current where busway system was installed, thermal overload test, water immersion test, cold shock temperature test and thermal cycle test were performed. And we examined changes in characteristics and abnormality after tests. From results, the test items presented to evaluate performance and reliability of the epoxy insulated busway system were confirmed to be appropriate in this paper, and the performance of the product was also confirmed to be excellent for reliability tests.

A Study on the Usefulness of Subjective Lumbar Instability Factor for Respiratory Pattern Change and Abdominal Mobility in Peoples with CLBP (만성허리통증자의 호흡 패턴과 배부 운동성 변화에 대한 주관적 허리부위 불안정성 요소의 유용성에 관한 연구)

  • Ki, Chul;Lee, Kwan-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.206-214
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    • 2020
  • This study examined the correlation between the respiratory pattern change (RPC) and abdominal mobility (AM) according to the positive result of the subjective lumbar instability factor (SLIF) in people with chronic low back pain (CLBP). Thirty-six adults with CLBP participated in this study. Twenty-eight items of the SLIFs were examined, and the subjects were divided into three groups according to the positive response numbers (PRN). After the change lists were scored, three RPC scores [costo-diaphragmatic RPC (CDRPC), breath hold change (BHC), and total RPC (TRPC)] were obtained. The abdominal mobility (AM) was measured between the maximal inspiration and exhalation at the xiphoid (AM1) and the 10th rib (AM2) level of the trunk. The results showed that the RPC score and AM were compared according to the positive response number of SLIF, and the relationship between them was analyzed. A positive correlation was observed between the SLIF positive response number and CDRPC score, BHC score, and total RPC score, and a negative correlation was observed between the SLIFs positive response number and AM1 and AM2. Based on the results of this study, the combination of SLIF positive responses can be a predictor of non-physiological respiratory pattern changes in people with CLBP. Clinically, this prediction is expected to help save time for screening and improve the efficiency of therapy.

The Mechanism of the Influence of Advanced Selling on Consumer Choice (사전예약을 통한 구매결정이 소비자의 선택에 미치는 영향력의 작동원리에 관한 실증연구)

  • Kim, Kyung-Ho;Lee, Hyoung-Tark;Seo, Heon-Joo
    • Journal of Distribution Science
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    • v.14 no.6
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    • pp.81-87
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    • 2016
  • Purpose - In recent, a research finds that advanced selling can influence a consumer's choice(Kim et al., 2013). Advanced selling is defined as the new product launching strategy which company allows consumers to preorder new product before its release(Chu & Zhang, 2011). Prior researches have focused on the benefits of advanced selling(e.g., information gathering for demand prediction, an advantage for pricing strategy, and so on) for companies using this strategy(Chen, 2001; Chu & Zhang, 2011; Li & Zhang, 2013; Tang et al., 2004; Xie & Shugan, 2009). However, Kim et al.(2013) find it can also influence a consumer's choice. In detail, they suggest that when consumers use advanced selling, they are likely to prefer high-performance options rather than low-price options based on construal level theory(Trope & Liberman, 2003). In this paper, we tried to expand the prior researches for finding the mechanism of the influence of advanced selling on a consumer's choice. The purpose of this research is to test the mediating effect on the influence of advanced selling. Research design, data, and methodology - To find the mechanism of the influence of advanced selling, we designed an experiment for testing mediation effect. we recruited 93 students from a university. We assigned participants into one of two groups using randomization method. The participants with each group were given a scenario describing the sales strategy. Finally, they made a choice between high-performance option and low-price option. Sequentially, they also responded some questions for testing mediation effect. Results - First, we replicated prior research to test the influence of advanced selling. As a result, we could find that consumers prefer the high-performance option when they preorder it to purchase at the time of consumption. Thus, the replication result is the same as prior research. Second, we tested that advanced selling can influence the perception of temporal distance. The results confirmed that consumers perceived longer temporal distance in advanced selling condition(β = 1.575, SE = 0.272, p < 0.001). Third, we predicted that temporal distance can increase the importance of desirable attributes and decrease the importance of feasible attributes. The results suggested that temporal distance decreased significantly the importance of attributes related to feasibility(β = -0.19, SE = 0.07, p < 0.01), however, it had non-significant effect on increasing the importance of desirable attributes. Finally, we used Sobel-test for testing mediation effect, and it confirmed that the importance of feasible attributes had mediating role of the influence of advanced selling(Sobel test statistic = -2.110, SE = 0.111, p < 0.05). Conclusions - In this paper, we tried to find the mechanism of the influence on advanced selling from a consumer's choice. With an experiment, we confirmed that the importance of feasible attributes could mediate the effect on advanced selling. Therefore, we suggested some theoretical and practical contributions from this research. Finally, we discussed research limitations and suggested future research topics.

Physiological Adaptation of Nitrate Uptake by Phytoplankton Under Simulated Upwelling Conditions (모의 용승조건하에서 식물 플랑크톤 질산염 흡수기작의 생리적 적응)

  • YANG Sung Ryull
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.5
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    • pp.782-793
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    • 1997
  • To study the physiological adaptation (shift-up) of phytoplankton under the simulated upwelling conditions, nitrate uptake capacity of Dunaliella tertiolecta batch culture was measured in the laboratory using the stable isotope $^{15}N-KNO_3$. Contrary to the expected, there was no significant relationship between the maximum $V_{NO3}$ (nitrogen specific nitrate uptake rate) and the initial nitrate concentration. However, there was a strong relationship between the maximum $\rho_{NO3}$ (nitrate transport rate) and the initial nitrate concentration of $<25\;{\mu}M$, which was also influenced by the physiological status of the culture. The increase in $V_{NO3}$ was mainly due to the increase in PON (particulate organic nitrogen) concentration and partly due to the increase in $V_{NO3}$. When the phytoplankton population was severely shifted-down, the physiological adaptation of nitrate uptake was significantly inhibited at high initial nitrate concentrations. The timing of the maximum $V_{NO3}$ or $\rho_{NO3}$ was related to the initial nitrate concentration. At higher initial nitrate concentrations, maxima in $V_{NO3}$ and $\rho_{NO3}$ occurred 1 or 2 days later than at lower nitrate concentrations. This relationship was the opposite to the prediction from the shift-up model of Zimmerman et al. (1987), The shift-up process is apparently controlled by an internal time sequence and the initial nitrate concentration, but the magnitude of $V_{NO3}$ was affected little by changes in nitrate concentration.

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Relationships between Health, Depression, Memory Self-Efficacy and Metamemory in Adults (성인의 건강, 우울, 기억, 자기효능과 메타기억과의 상관관계 연구)

  • Kim, Jeong-Hwa;Kang, Hyun-Sook
    • The Korean Journal of Rehabilitation Nursing
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    • v.1 no.1
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    • pp.61-71
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    • 1998
  • Defining prediction variables related to metamemory for the adults in aging process has worthwhile meaning from the perspective that the produced results can be helpful to reducing the difficulty of memorizing efforts and it can also enhance quality of life of aged. This study attempted to analysis relationship between perceived health status, depression, memory self-efficacy and meta memory for the subjects of middle age and old age adults. This study was designed by adopting descriptive correlational analysis method for the 468 middle and old age adults who are living in Seoul. Samples were selected by convenience sampling. Data collection was done over 1 month period in june 1998. The instruments used in this study were health status measuring scale including depression measuring scale, memory self efficacy measuring scale and metamemory measuring scale which were verified for reliability. Data collected were analized by using SPSS for frequency, Peason correlation, t-test and ANOVA according to the variables character and the study purposes. Results of the study were as follows. 1. Relationship between perceived health status, depression, memory self-efficacy and metamemory. Relational analyses between perceived health status, depression, memory self-efficacy and metamemory supported the hypotheses of 1st, 2nd and 3rd(p < .01). These results suggested that the aged perceived great health status then their memory self-efficacy, and metamemory showed the high scores. In the case of depression when its level became decreased metamemory was inclined to increased. Thus, it is identified that strong relationship exists between these variables. 2. Perceived health status, depression, memory self-efficacy by subject's general characteristics. Scores of perceived health status were high in the group of man compared to the group of women, and also highly educated group showed great perceived health status. Group of persons having occupation showed high score of perceived health status and low depression score. The score of memory self-efficacy and metamemory showed higher in the middle aged than the old aged. The high scores of memory self-efficacy and metamemory were found in the group of highly educated people and who have continuing education. The high scores of memory self-efficacy were found in the group of persons having their job and high metamemory scores found in the group of persons having religion. In summary, the greater perceived health status and memory self-efficacy, the more metamemory scores were likely increased and the more depression level was decreased, the more metamemory was likely increased. Also it was found that general characteristics like educational level, continuing education and religion influenced the metamemory of the aged. Therefore, prevention the aged from getting depression and activation of health promotion are needed to delay time of memory loss.

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A Study on the Eco-Environmental Change of Coastal Area by the Sea Level Rise (해수면 상승에 따른 해안지역 생태환경 변화)

  • Kim, Nam-Shin;Lee, Chang-Seok
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.3
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    • pp.53-63
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    • 2010
  • The global sea level rise has an effect on eco-environmental change by the inundation and erosion in the coastal area. Forecasting model on the change of morpho-ecological environments by the sea level change will give us information for coastal area management by predicting environmental changes of the up-coming future. This research aimed to foresee eco-environmental changes by the sea level rise in coastal area. Prediction model used SLAMM model developed to forecast coastal changes by IPCC scenario. The model predicted centennial environmental changes in the mouth of Han river and Nakdong river, Suncheon and Hampyeung bay as case areas. To sum up the research findings, in the estuary of the Han river, tidal flat was gradually disappeared from the year 2075, scrubmarsh and saltmarsh belts were developed. In the Nakdong River estuary, scrubmarsh was decreased from the year 2025, tidal flat was deposited from the year 2050, and also, the Gimhae plain was partially inundated, and wetlands were formed. In the Hampyeung bay, saltmarsh was deposited in the year 2025, tidal flat expanded until 2050 was partially submerged after that time. Tidal flat of Suncheon bay was disappeared by the inundation after 2025, and saltmarsh was developed in the embayment.

The Change of Industrial Distribution Pattern by Worker Status Classification : Busan, 1994~2004 (종사상 지위분류에 따른 산업분포변화: 부산, 1994~2004)

  • Kang, In-Joo;Nam, Kwang-Woo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.10 no.4
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    • pp.111-121
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    • 2007
  • Diagnosis and Prediction of urban industrial structure is a key subject for establishment of sustainable urban development plan. By this time, studies of industry-related urban spatial structure have been concentrated on measurement of space distribution by industry type mainly using data about urban industries or total worker numbers. Now, status of workers become an important issue so this study analyzed qualitative change of urban industrial structure in the view of space using work status classification system. For that, data for work status in 1994 and 2004 were collected in towns and villages, and space analysis units were coincided based on change data between 1994 and 2004. Then, it analyzed spatial distribution pattern of employment through qualitative standard called work status using GIS. The analysis results by work status type of Busan industrial structure in GIS circumstance were as below. First, traditional labor intensive industries met a limit and service and wholesale/retail sale industries went to be poor livelihood. Therefore, Busan's employment rate should be decreased and worker numbers were statistically increased, however, irregular and non-wage workers were suddenly increased. So, it was determined that the quality of employment in Busan area came down. Second, a traditional downtown area has dwindled; on the other hand, employment has been increased in new town or new industrial complex and in the area developed services rather than the manufacturing industry. It is expected that the result of this study may be meaningful as data to prepare for longterm industrial development plan through qualitative evaluation called work status as well as to make behavior pattern of industrial structure which is basis of urban development.

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