• Title/Summary/Keyword: sampling points

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The Applicability of Minimum Entropy Deconvolution Considering Spatial Distribution of Sampling Points (지하수 함양량 추정시 공간상에서의 자료 Sampling 방법에 따른 Minimum Entropy Deconvolution의 적용성에 관한 검토)

  • Kim Tae-Hee;Kim Yong-Je;Lee Kang-Keun
    • Journal of Soil and Groundwater Environment
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    • v.11 no.3
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    • pp.52-58
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    • 2006
  • Kim and Lee (2005) suggested Minimum Entropy Deconvolution (MED) to estimate the temporal sequence of the relative recharge. However this study by Kim and Lee (2005) was just related to the verification of the conceptual approach with MED. In this study, we try to characterize the applicability of MED in the case of spatially heterogeneous recharge (distance from recharge area). Simulated results were recorded with some specific sampling points. Estimated results from this study show higher than 0.8 in cross-correlation with the original recharge sequence. In addition, the physical and mathematical meanings of the applied filter length was also investigated. It was revealed that the length of filter is highly related to the spatial distance between recharge area and the monitoring site, and the apparent shape of hydraulic head change.

Improvement of Accuracy for Human Action Recognition by Histogram of Changing Points and Average Speed Descriptors

  • Vu, Thi Ly;Do, Trung Dung;Jin, Cheng-Bin;Li, Shengzhe;Nguyen, Van Huan;Kim, Hakil;Lee, Chongho
    • Journal of Computing Science and Engineering
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    • v.9 no.1
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    • pp.29-38
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    • 2015
  • Human action recognition has become an important research topic in computer vision area recently due to many applications in the real world, such as video surveillance, video retrieval, video analysis, and human-computer interaction. The goal of this paper is to evaluate descriptors which have recently been used in action recognition, namely Histogram of Oriented Gradient (HOG) and Histogram of Optical Flow (HOF). This paper also proposes new descriptors to represent the change of points within each part of a human body, caused by actions named as Histogram of Changing Points (HCP) and so-called Average Speed (AS) which measures the average speed of actions. The descriptors are combined to build a strong descriptor to represent human actions by modeling the information about appearance, local motion, and changes on each part of the body, as well as motion speed. The effectiveness of these new descriptors is evaluated in the experiments on KTH and Hollywood datasets.

Bathymetric mapping in Dong-Sha Atoll using SPOT data

  • Huang, Shih-Jen;Wen, Yao-Chung
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.525-528
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    • 2006
  • The remote sensing data can be used to calculate the water depth especially in the clear and shallow water area. In this study, the SPOT data was used for bathymetric mapping in Dong-Sha atoll, located in northern South China Sea. The in situ sea depth was collected by echo sounder as well. A global positioning system was employed to locate the accurate sampling points for sea depth. An empirical model between measurement sea depth and band digital count was determined and based on least squares regression analysis. Both non-classification and unsupervised classification were used in this study. The results show that the standard error is less than 0.9m for non-classification. Besides, the 10% error related to the measurement water depth can be satisfied for more than 85% in situ data points. Otherwise, the 10% relative error can reach more than 97%, 69%, and 51% data points at class 4, 5, and 6 respectively if supervised classification is applied. Meanwhile, we also find that the unsupervised classification can get more accuracy to estimate water depth with standard error less than 0.63, 0.93, and 0.68m at class 4, 5, and 6 respectively.

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Nurses' Monitoring Practice for Adverse Drug Reactions (약물 유해 반응에 대한 간호사의 모니터링 실천에 관한 연구)

  • Kim, Hyun-Jin;Lee, Seon-Hye
    • Journal of Korean Academy of Nursing Administration
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    • v.22 no.1
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    • pp.91-98
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    • 2016
  • Purpose: The aim of this study was to identify the relationship between nurses' knowledge of adverse drug reactions (ADR), attitudes, and monitoring practices and to establish an effective ADR reporting system and provide baseline data for its activation. Methods: The participants in this study were chosen by convenience sampling and included 182 nurses working at major general hospitals that operate a Regional Drug Safety Center. Data were collected from June 1 to 12, 2015 and analyzed using Cronbach's ${\alpha}$, descriptive statistics, independent t-test, one way ANOVA, Pearson correlation coefficient and stepwise regression with the SPSS program. Results: The nurses' average score for knowledge was 7.62 points, for attitude, 41.04 points and for monitoring practices, 34.22 points. ADR monitoring practices positively correlated with knowledge (r=.19, p=.011), attitude (r=.41, p<.001), drug performance competency (r=.54, p<.001), and drug education satisfaction (r=.54, p<.001). Drug performance competency, drug education satisfaction, and attitudes explained 42.0% of the ADR monitoring practices (Adj $R^2=.42$, F=43.95, p<.001). Conclusion: In order to facilitate and encourage nurses' voluntary monitoring practice of ADR, efforts must be made to create positive attitudes toward ADR, and to increase drug performance competency and drug education satisfaction.

Air Quality Evaluation with Passive Samplers for Large Cities (Passive Sampler를 이용한 대도시의 대기질 평가)

  • Jeon, Eui-Chan;Kim, Shin-Do;Choi, Kum-Chan
    • Journal of Environmental Impact Assessment
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    • v.7 no.2
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    • pp.83-88
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    • 1998
  • Filter badge type sampler has not been widely used to evaluate air quality over large cities in Korea while it can be successfully used for multi-point sampling and analysis. We evaluated the passive sampler as a new tool to monitor air quality over large cities. We latticed Metropolitan Seoul into $2{\times}2Km$ to give 136 points. $NO_2$ concentrations were measured at all the points in the Spring and Summer of 1997. According to the passive sampler data, natural green zones generally recorded lower $NO_2$ concentrations than major streets and traffic congestion areas. Passive samplers with abundant 136 points gave more detailed picture of $NO_2$ distribution while auto-monitoring network did not clearly provide the characteristics of local land use. Also, passive samplers gave 15% higher values than auto-monitoring network. The correlation between the two values appears very high judging from the regression slope of 0.92 and correlation coefficient of 0.91. This study clearly demonstrates the effectiveness of the passive sampler as a tool to monitor air quality over large cities.

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Knee-driven many-objective sine-cosine algorithm

  • Hongxia, Zhao;Yongjie, Wang;Maolin, Li
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.2
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    • pp.335-352
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    • 2023
  • When solving multi-objective optimization problems, the blindness of the evolution direction of the population gradually emerges with the increase in the number of objectives, and there are also problems of convergence and diversity that are difficult to balance. The many- objective optimization problem makes some classic multi-objective optimization algorithms face challenges due to the huge objective space. The sine cosine algorithm is a new type of natural simulation optimization algorithm, which uses the sine and cosine mathematical model to solve the optimization problem. In this paper, a knee-driven many-objective sine-cosine algorithm (MaSCA-KD) is proposed. First, the Latin hypercube population initialization strategy is used to generate the initial population, in order to ensure that the population is evenly distributed in the decision space. Secondly, special points in the population, such as nadir point and knee points, are adopted to increase selection pressure and guide population evolution. In the process of environmental selection, the diversity of the population is promoted through diversity criteria. Through the above strategies, the balance of population convergence and diversity is achieved. Experimental research on the WFG series of benchmark problems shows that the MaSCA-KD algorithm has a certain degree of competitiveness compared with the existing algorithms. The algorithm has good performance and can be used as an alternative tool for many-objective optimization problems.

Knowledge, Experience, and Attitudes of Nurses at Long-Term Care Hospitals regarding Advance Directives

  • Go Eun, Park;Nae Young, Lee
    • Journal of Hospice and Palliative Care
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    • v.25 no.4
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    • pp.139-149
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    • 2022
  • Purpose: The purpose of this study was to promote awareness of the need for advance directives (ADs) and to provide baseline data for the development of a nurse training program about ADs. Methods: Nurses at eight long-term care hospitals in Busan and South Gyeongsang Province (N=143) were recruited using the random sampling method from December 2018 to January 2019. Data were obtained using a structured self-reported questionnaire to assess their knowledge, experience, and attitudes regarding ADs. Data were analyzed in SPSS 22.0 using descriptive statistics, the t-test, analysis of variance, the Scheffé test, Pearson's correlation coefficient, and stepwise multiple regression analysis. Results: The mean scores were 7.79±1.39 points for knowledge, 1.92±2.00 points for experience, and 2.80±0.24 points for attitudes regarding ADs. Knowledge and experience (r=0.32, P<0.001) had a positive correlation with knowledge and attitudes (r=0.17, P=0.39). Conclusion: According to the results, nurses generally had a high level of knowledge regarding ADs, which resulted in a positive attitude toward ADs. However, they had little experience with ADs. Therefore, nurses' must develop both direct and indirect experience with ADs using a practical training program to strengthen their clinical competency regarding ADs.

A Study on Progressive Sampling Method Using Contour Lines (등고선(等高線)을 이용(利用)한 표본추출법(標本抽出法)에 관한 연구(硏究))

  • Lee, Suk Chan;Shin, Bong Ho;Jung, Sung Ho;Cho, Young Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.5 no.2
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    • pp.67-73
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    • 1985
  • In Digital Terrain Model(DTM), more accurate data acquisition method is of importance. This paper has the purpose of accuracy analysis of progressive sampling method, one of data acquisition method. Especially, The following in accuracy analysis are compared and analyzed. -Comparison and analysis for position error between the digital contour lines using digital terrain model and the conventional contour lines using A-10 Plotter. -Analysis for height error of interpolation points according to application of progressive sampling method. For above numerical tests, Computer Program related to auto-carto of contour lines was made up. As a result of tests, threshold and sampling criterion have close of mutual relation to accuracy. Particularly, it was found that auto-carto of contour lines-threshold of 1.0 m and standard criterion-almost concurred in conventional contour lines.

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Comparison of Sampling Methods for Determining Airborne Mixture of Organic Solvents (공기중 유기용제 혼합물 측정방법의 비교연구)

  • Chun, Mee Hye;Paik, Nam Won
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.1 no.1
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    • pp.16-28
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    • 1991
  • A study on comparison of standard charcoal tube method, infrared gas analyzer, and detector tube method were conducted. Measurements were performed simultaneously at same sampling points in an air chamber containing benzene, toluene and xylene vapors. Charcoal tube samles were collected at sampling flowrates of 0.05, 0.2, 0.5, and 1.0 1pm. Results are as follows : 1. Coefficients of variation of results with charcoal tube method for bezene, toluene and xylene mixture vapor were 14.34 % in benzene(0.28-11.12 ppm), 9.20 % in toluene (2.68-135.09 ppm) and 10.21 % in xylene (2.56-82.64 ppm), respectively. 2. Results of infrared gas analyzer in mixture air were non-specific on benzene and toluene. Ratio of results of infrared gas analyzer to those of charcoal tube on benzene, toluene and xylene were 696.4 %, 30.3 % and 36.6 %, respectively. 3. Ratio of responses of detector tubes to those of charcoal tube were 49.4 % in benzene, 22.1 % in toluene and 223.9 % in xylene. Xylene detector tube were interfered by toluene greately. 4. Collection efficiencies of charcoal tubes at low concentraton(benzene : 1 ppm, toluene : 10 ppm, xylene : 10 ppm) were stable on various flowrate from 0.05 to 1.0 1pm, but at high concentrations the efficiency decreased at high flowrate above 0.5 1pm. 5. Within the saturation capacity of charcoal, collection effiency decreased at 0.5-1.0 1pm. Smpling feowrates of 0.05-0.20 1pm were appropriate for sampling organic vapors.

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Accuracy Evaluation of the Alternative Site Blood Glucose Test Using Error Grid (에러그리드를 사용한 대체부위 혈당검사의 유용성 검증)

  • Park, Kyung-Soon;Cha, Eun-Jong
    • Journal of Biomedical Engineering Research
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    • v.32 no.1
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    • pp.25-31
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    • 2011
  • Blood glucose information is important for self regulation in daily life, but the frequency of self test remains to be only 17%(9 tests/month) in Korea, mainly due to pain during blood sampling. The present study tried to validate the clinical efficacy of the forearm as an alternative sampling site with minimized pain. Capillary blood was sampled both on the index finger($G_F$) and the forearm($G_A$), immediately followed by glucose measurements in 531 subjects, 25 who visited the Health Enhancement Center of C University Hospital, then venous blood($G_V$) was sampled for glucose test. The blood glucose concentration measured on the forearm was closer to the venous glucose than on the finger. The mean difference between $G_V$and $G_F$ was only 10 mg/dL well within the internationally accepted error limit. Error grid analyses of $G_F-G_V$, $G_A-G_V$ and $G_A-G_F$ revealed that the number of data points in regions A and B took 100%, 99.8%, and 97.9%, respectively. These results demonstrate the forearm blood glucose test is not only accurate but also clinically valid. Therefore, the forearm blood glucose test can be a useful way of self managing the chronic diabetes with minimized sampling pain.