• Title/Summary/Keyword: statistical assessment

Search Result 1,561, Processing Time 0.033 seconds

Study on the Ratio of Greenness in Residential Complex Development in the Process of Prior Environmental Review System (사전환경검토 대상 택지개발사업의 녹지율분석에 관한 연구)

  • Kim, Sung-Ok;Lee, Sang-Don
    • Journal of Environmental Impact Assessment
    • /
    • v.16 no.5
    • /
    • pp.311-318
    • /
    • 2007
  • This study was conducted based on the 115 development projects of residential areas during 2001-2006 to investigate the current status of park green areas. Prior Environmental Review System (PERS) was categorized into regions, scales, and time of the projects, and regression model was used for a statistical analysis. The ratios of greenness of Seoul and Gyunggi province were greater than those of other regions whereas the ratios of greeness of Cheonnam, Chungbuk, and Jeonbuk provinces showed smaller percentage of green areas. Secondly as the scales of development get bigger areas of greenness become larger indicating a large scale residential development projects are favorable for securing green areas. Thirdly the correlation between planned area and green areas, and that between planned population and the ratio of greenness are relatively low (P>0.05). This implies green areas are not a good indicator but a concrete guideline for green areas. Fourthly the ratio of greenness of small scale project is not reached to 10% so that it is recommended to secure over one million $m^2$ areas for development project.

Reproducibility Assessment of K-Means Clustering and Applications (K-평균 군집화의 재현성 평가 및 응용)

  • 허명회;이용구
    • The Korean Journal of Applied Statistics
    • /
    • v.17 no.1
    • /
    • pp.135-144
    • /
    • 2004
  • We propose a reproducibility (validity) assessment procedure of K-means cluster analysis by randomly partitioning the data set into three parts, of which two subsets are used for developing clustering rules and one subset for testing consistency of clustering rules. Also, as an alternative to Rand index and corrected Rand index, we propose an entropy-based consistency measure between two clustering rules, and apply it to determination of the number of clusters in K-means clustering.

Estimating Predicted Environmental Concentration of Veterinary Antibiotics in Manure and Soil

  • Kwon, A-Young;Kim, Sung Chul
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.48 no.2
    • /
    • pp.100-104
    • /
    • 2015
  • Adverse effect of veterinary antibiotics (VAs) released into environment has been issued recently and concerns about analysis and management for VAs in the environment were increased. Main objective of this research was to calculate predicted environmental concentration (PEC) of the VAs in soil based on avaiable statistical data and result of previous study such as consumption rate and physiological properties of VAs. Total of 5 VAs, Chlortetracycline (CTC), Oxytetracycline (OTC), Sulfadimethoxine (SDX), Sulfamethazine (SMT), and Tylosin (TYL) were examined. Result showed that calculated PEC value in manure and soil was ordered as SMT > TYL > SDX > CTC > OTC. Range of calculated value for manure and soil was 0.50-67.04 and $0.48-64.45mg\;kg^{-1}$ respectively. Comparing to measured concentration of VAs in manure and soil, lower concentration of VAs in manure and soil was evaluated due to fate and degradation of VAs in manure and soil. Overall, evaluated simple modeling for calculating PEC of VAs in manure and soil can be adapted for preliminary screening purpose in environmental risk assessment and more refined modeling is necessary to examine detailed assessment of VAs in manure and soil.

Stator Insulation Quality Assessment for High Voltage Motors Based on Probability Distributions

  • Kim, Hee-Dong;Kim, Chung-Hyo
    • Journal of Electrical Engineering and Technology
    • /
    • v.3 no.4
    • /
    • pp.571-575
    • /
    • 2008
  • Stator insulation quality assessment for high voltage motors is a major issue for the reliable maintenance of industrial and power plants. To assess the condition of stator insulation, nondestructive tests were performed on the sixty coil groups of twelve motors. After completing the nondestructive tests, the AC voltage applied to the stator winding was gradually increased until insulation failure in order to obtain the breakdown voltage. The stator winding of each motor was classified into five coil groups; one group with healthy insulation and four groups with four different types of artificial defects. To analyze the breakdown voltage statistically, Weibull distribution was employed for the tests on the fifty coil groups of ten motors. The 50th percentile values of the measured breakdown voltages based on the statistical data of the five coil groups of ten motors were 26.1kV, 25.0kV, 24.4kV, 26.7kV and 30.5kV, respectively. Almost all of the failures were located in the line-end coil at the exit of the core slot. The breakdown voltages and the types of defects showed strong relation to the stator insulation tests such as in the case of dissipation factor and ac current. It is shown that the condition of the motor insulation can be determined from the relationship between the probability of failure and the type of defect.

Clinical Nurses' Knowledge and Attitudes on Pain Management (임상간호사의 통증관리에 대한 지식과 태도)

  • Hyun, Ju;Park, Kyung Sook
    • Korean Journal of Adult Nursing
    • /
    • v.12 no.3
    • /
    • pp.369-383
    • /
    • 2000
  • The purpose of this study was to understand clinical nurses' knowledge and attitudes on pain management. The subject of the study were 254 nurses working at two hospitals affiliated with a university in Seoul. The questionnaires included four areas: general knowledge on pain, knowledge on the use of analgesia, knowledge and implementation on the pain assessment scales and pain interventions and nurses' general characteristics. The data were analyzed with descriptive statistics, analysis of variance, LSD test and t-test using SPSS statistical package. The results were as follows. 1. The mean score of the general pain knowledge was 61.46 and that of knowledge on the use of analgesia was 52.19. 2. Most nurses(74%) answered with hesitation about injecting narcotic analgesia to patients. 3. The pain assessment scale which nurses knew (57.5%) and used(48.0%) extremely was a simple descriptive scale. 4. The pain intervention which nurses knew (94.5%) and implemented(92.1%) extremely was to inject analgesia. 5. The number of nurses who had learned about pain management was 49 of 254(19.3%). 6. Nurses' knowledge on the use of analgesia was of relevance to having learned pain management, but general pain knowledge was not so relevant. According to this research, I suggest the following. 1. It is necessary to develop an education program with actual practice and intervention which nurses can perform for themselves. 2. It is necessary to continuously educate about pain management in clinical wards.

  • PDF

Nonlinear Quality Indices Based on a Novel Lempel-Ziv Complexity for Assessing Quality of Multi-Lead ECGs Collected in Real Time

  • Zhang, Yatao;Ma, Zhenguo;Dong, Wentao
    • Journal of Information Processing Systems
    • /
    • v.16 no.2
    • /
    • pp.508-521
    • /
    • 2020
  • We compared a novel encoding Lempel-Ziv complexity (ELZC) with three common complexity algorithms i.e., approximate entropy (ApEn), sample entropy (SampEn), and classic Lempel-Ziv complexity (CLZC) so as to determine a satisfied complexity and its corresponding quality indices for assessing quality of multi-lead electrocardiogram (ECG). First, we calculated the aforementioned algorithms on six artificial time series in order to compare their performance in terms of discerning randomness and the inherent irregularity within time series. Then, for analyzing sensitivity of the algorithms to content level of different noises within the ECG, we investigated their change trend in five artificial synthetic noisy ECGs containing different noises at several signal noise ratios. Finally, three quality indices based on the ELZC of the multi-lead ECG were proposed to assess the quality of 862 real 12-lead ECGs from the MIT databases. The results showed the ELZC could discern randomness and the inherent irregularity within six artificial time series, and also reflect content level of different noises within five artificial synthetic ECGs. The results indicated the AUCs of three quality indices of the ELZC had statistical significance (>0.500). The ELZC and its corresponding three indices were more suitable for multi-lead ECG quality assessment than the other three algorithms.

A Study on Measuring the Similarity Among Sampling Sites in Lake Yongdam with Water Quality Data Using Multivariate Techniques (다변량기법을 활용한 용담호 수질측정지점 유사성 연구)

  • Lee, Yosang;Kwon, Sehyug
    • Journal of Environmental Impact Assessment
    • /
    • v.18 no.6
    • /
    • pp.401-409
    • /
    • 2009
  • Multivariate statistical approaches to classify sampling sites with measuring their similarity by water quality data and understand the characteristics of classified clusters have been discussed for the optimal water quality monitering network. For empirical study, data of two years (2005, 2006) at the 9 sampling sites with the combination of 2 depth levels and 7 important variables related to water quality is collected in Yongdam reservoir. The similarity among sampling sites is measured with Euclidean distances of water quality related variables and they are classified by hierarchical clustering method. The clustered sites are discussed with principal component variables in the view of the geographical characteristics of them and reducing the number of measuring sites. Nine sampling sites are clustered as follows; One cluster of 5, 6, and 7 sampling sites shows the characteristic of low water depth and main stream of water. The sites of 2 and 4 are clustered into the same group by characteristics of hydraulics which come from that of main stream. But their changing pattern of water quality looks like different since the site of 2 is near to dam. The sampling sites of 3, 8, and 9 are individually positioned due to the different tributary.

Biomarker-Based Exposure to Phthalates and Related Factors with Demographics (프탈레이트의 노출 정도 및 인구학적 특성과의 관련요인)

  • 구정완;이강숙;박정일;구현정;이병무
    • Toxicological Research
    • /
    • v.19 no.4
    • /
    • pp.297-301
    • /
    • 2003
  • To investigate biomarker-based exposure to phthalates and related factors with demographics, 100 subjects who had participated in comprehensive health check-up were selected. We collected demographics through questionnaires and analyzed urine samples for 5 phthalates. Statistical likelihoods and regression methods were applied for data analysis using censored data. The highest levels of urine phthalates were 216$\mu\textrm{g}$/ml in di-isodecyl phthalate, 29.0$\mu\textrm{g}$/ml in di-butyl phthalate, 5.78$\mu\textrm{g}$/ml in di-(2-ethylhexyl) phthalate. The median values of di-(2-ethylhexyl) phthalate were 0.2340 $\mu\textrm{g}$/ml for male smokers, 0.0399 $\mu\textrm{g}$/ml for male non-smokers and 0.0085 $\mu\textrm{g}$/ml for female non-smokers, respectively. Di-(2-ethylhexyl) phthalate, benzyl butyl phthalate and di-isodecyl phthalate were higher in males than in females. In addition, mono-2-ethylhexyl phthalate was decreased with age. Our findings suggest that there might be significant demographic variations in exposure and/or metabolism of phthalates, and that health-risk assessment for phthalate exposure in humans should consider different potential risk groups.

Statistics and Probability Distribution of Total Coliforms in Wastewater (하수에서의 대장균수 확률분포 특성 분석)

  • Jun, Sang Min;Song, Inhong;Jeong, Han Seok;Kang, Moon Seong;Park, Seung Woo
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.55 no.3
    • /
    • pp.105-111
    • /
    • 2013
  • Probability distribution of microbes in wastewater is a crucial factor to be determined for microbial risk assessment associated with its reuse. The objective of this study was to investigate probability distribution of an indicator microorganism in wastewater. Daily total coliform counts measured from nationwide wastewater treatment plants in 2010 by the Ministry of Environment were used for statistical analysis. Basic statistics and probability distributions were estimated in the three different spatial scales using the MS Excel software and FARD2006 model. Overall, wastewater from manure and livestock treatment plants demonstrated greater median coliform counts than from sewage and village treatment plants. Generalized logistic (GLO) and 2-parameter Weibull (WBU2) appeared to be the two probability distributions that fitted best for total coliform numbers in wastewater. The study results of microbial statistics and probability distributions would provide useful data for quantitative assessment of microbial risk from agricultural wastewater reuse.

The Effects of Treatment With a TETRAX on Balance and Mobility in Acute Stroke Patients (균형능력 운동치료 시스템을 이용한 치료가 급성기 뇌졸중 환자의 균형과 이동능력에 미치는 영향)

  • Lee, Nam-Hyun;Lee, Jin;Lee, Kang-Noh
    • Physical Therapy Korea
    • /
    • v.17 no.3
    • /
    • pp.11-19
    • /
    • 2010
  • The purpose of the study was to determine the effects of balance training with 'TETRAX' system, a balance training and assessment tool, on balance and mobility in acute hemiplegic patients. Nineteen matched subjects were assigned randomly into either an experimental group or a control group. An experimental group with 10 subjects received balance training with 'TETRAX' exercise program and conventional physical therapy interventions 5 times per week during 4 weeks. A control group with 9 subjects received conventional physical therapy interventions 5 times per week during 4 weeks. Outcome measures were taken before and after 4 weeks of interventions using the Stroke Rehabilitation Assessment of Movement (STREAM), the Berg Balance Scale (BBS), gait speed, and the fall down index. Results indicated that both exercise groups improved significantly in STREAM, BBS, and gait speed (p<.05). The experimental group had a little improvement than the control group. Both exercise groups did not show statistical significance in fall down index (p<.05). Following 4 weeks of intervention, except gait speed there was no statistically significant difference between two groups. However, these findings suggest that conventional physical therapy interventions with visual feedback training could be effective on improving balance and mobility than conventional physical therapy alone in acute hemiplegic patients.