• Title/Summary/Keyword: statistical assessment

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Strength Prediction Equations for High Strength Concrete by Schmidt Hammer Test (슈미트 해머 시험에 의한 고강도 콘크리트의 강도 추정식)

  • Kwon, Young-Wung;Park, Song-Chul;Kim, Min-Su
    • Journal of the Korea Concrete Institute
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    • v.18 no.3 s.93
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    • pp.389-395
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    • 2006
  • For the assessment of exsiting concrete structures, it is important to get the real strength of concrete. The load test or core test has many problems due to cost time, easiness, structural damage, and reliability and so on. Thus, various non-destructive test and statistical analysis techniques for strength assessment have been developed. As a result the real strength of concrete can be obtained by both direct and indirect test. In this study, a series of experimental tests of core strength and Schmidt hammer tests on 3, 7, 14, 28, 90, 180, 365, and 730 days' were done for predicting the compressive strength of high strength concrete with 65.0MPa of 28-days' strength. Each experimental results was analyzed by simple regression analysis. Then, reliability level and error rate between the proposed equations and the existing ones was examined. However, the application of the exsisting equations was inadequate to high strength concrete, because they were conducted under normal strength concrete. Therefore, the following compressive strength equations were proposed for predicting the compressive strength of high strength concrete by Schmidt hammer test. The proposed equations by Schmidt hammer test are as follows.

Improving the Detection of the Water Mains Underground Facilities (상수도 지하시설물 탐사 개선에 관한 연구)

  • Kim, Jae-Myeong;Lee, Byung-Woon;Choi, Yun-Soo;Yoon, Ha-Su
    • Spatial Information Research
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    • v.18 no.4
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    • pp.23-32
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    • 2010
  • Water mains underground facilities are essential components to make up urban infrastructure. In order to manage these water mains underground facilities systematically and scientifically, GIS (Geographic Information System) had been constructed. For the sake of construction of GIS for water mains underground facilities, an exact underground detection and the construction of DB (Data Base) for buried water mains underground facilities should be preceded. In this study, in order to find out the ways to improve exact detection rate of data, the statistical analysis for the causes of detection raw degradation was done, and standardization methods of detection through a case study were suggested, When water mains underground facilities were measured, the detection of non-metallic water pipes was not carried out. The reason was that the results of detection was uncertain and detection was difficult because the assessment of public measurements was vulnerable. Moreover, due to the absence of standardized operating regulations for detection, systematic surveys weren't conducted. In this study, methods to standardize works over the detection of water mains underground facilities were presented so that we can improve the detection rate when we are doing that. As the proposals to improve detection rate, effective performance assessment over non-metallic pipes were presented, and related issues to supplement work regulations of public survey were described systematically.

The Comparative Analysis Study and Usability Assessment of Fat Suppressed 3D FSPGR T1 Technique and Fat Suppressed Isotropic 3D FSE T1 Technique when Examining MRI of Patient with Triangular Fibrocartilage Complex (TFCC) Tear (삼각 섬유성 연골(TFCC) 손상 환자의 자기공명영상 검사 시 Fat Suppressed 3D FSPGR T1 강조 기법에 대한 Fat Suppressed Isotropic 3D FSE T1 강조 기법의 비교 분석 및 유용성에 관한 평가)

  • Kang, Sung-Jin;Cho, Yong-Keun;Lee, Sung-Soo
    • Journal of the Korean Magnetics Society
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    • v.26 no.3
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    • pp.105-114
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    • 2016
  • In this study, For assessment of triangular fibrocartilage complex (TFCC) injury, we acquired images by fat suppressed 3D fast spoiled gradient recalled T1 and fat suppressed Isotropic 3D fast spin echo T1 techniques. For quantitative evaluation, measured signal to noise ratio and contrast to noise ratio and verified statistical significance between two imaging techniques by Mann-Whitney U verification. And for qualitative evaluation, marked 4-grade scoring (0: non diagnostic, 1: poor, 2: adequate, 3: good) on shape of TFCC, artifacts by partial volumes, description of the lesions by two radiologist, verified coincidence between 2 observer using Kappa-value verification. We used 3.0 Tesla MR equipment and 8-channel RF coil for imaging acquisition. As quantitative evaluation results, signal to noise ratio and contrast to noise ratio value of Isotropic 3D fast spin echo T1 technique is higher in every image sections, also between two imaging techniques by Mann-Whitney U verification was statistically significant (p < 0.05). As qualitative results, observer 1, 2 marked a higher grade on Isotropic 3D FSE T1 technique, coincidence verification of evaluation results between two observers by Kappa-value verification was statistically significant (p < 0.05). As a result, during MRI examination on TFCC injury, fat suppressed Isotropic 3D fast spin echo T1 technique is considered offering more useful information about abnormal lesion of TFCC.

Summer Patterns and Diel Variations of Fish Movements Using Fish Trap Sampling Technique in the Juksan Weir (죽산보의 어도에서 트랩 샘플링 기법을 이용한 하절기, 일주기별 어류 이동성 평가)

  • Han, Jeong-Ho;Ko, Dae-Geun;Lim, Byung Jin;Park, Jong-Hwan;An, Kwang-Guk
    • Journal of Environmental Impact Assessment
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    • v.21 no.6
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    • pp.879-891
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    • 2012
  • The objective of this study was to evaluate seasonal patterns and diel variations of fish movements in the Juksan Weir which was constructed in 2010 at the down-stream of Yeongsan-River watershed. For this study, we monitored day-and-night movement(24 Hr cycle) and seasonal fish migration(June ~ August) patterns in 2011 along with species compositions and abundances depending on the locations of the traps within the fishway. Total number of species sampled was 14 and the total number of individuals was 1,263 with only the size-fractions(as total length) of the fish < 20 cm during the study. Seasonal analysis of fish movement in the fish way showed that highest frequency in the movement occurred in June - July, which is closely associated with a spawning peak season. The most dominant species using the fishway was Squalidus chankaensis tsuchigae, and this species turned out to be 26.9% of the total in the use rate of fishway. Daily monitoring of fish movements showed that most frequent movements occurred between 18:00 PM and 21:00 PM when the fish have a feeding time generally. The migratory fish were not found in the fishway during the study. Mean current velocity during the study $0.42{\pm}0.02ms^{-1}$(n = 42), and there were no significant statistical differences(p > 0.05) among the daily and monthly velocities in the fishway. The use rate of fish passage, in terms of fish species, was 48%, compared with total sampling of fish species(29 species) at the down-river regions during the same period, indicating a low use rate. Further continuous long-term monitoring should be conducted to evaluate the impacts of the weir construction in the river.

A study of various factors related to satisfaction of complete denture wearers (총의치 장착자의 의치 만족도와 관련된 요인에 관한 연구)

  • Byun, Jin-Soo;Huh, Yoon-Hyuk;Cho, Lee-Ra;Park, Chan-Jin
    • Journal of Dental Rehabilitation and Applied Science
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    • v.32 no.2
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    • pp.109-116
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    • 2016
  • Purpose: The aim of this study was to evaluate correlations between denture satisfaction and various factors related to patients' and wearing dentures. Materials and Methods: Total 43 edentulous patients were recalled and they were wearing complete dentures fabricated more than one year ago. For patients' subjective assessment, the questionnaire based on the various literatures was developed and applied to patients for data acquisition. In addition, correlations were evaluated between subjective assessment and denture satisfaction score. For statistical analysis, Spearman correlation coefficient, multiple regression analysis, Mann-whitney U test and Kruskal-Wallis test were used to found out what the most considerable factors to denture satisfaction score (P < 0.05). Results: Denture satisfaction score of maxilla was higher than mandible (P < 0.05). In functional aspects, maxillary denture were received a favorable evaluation. Especially fit and pain causing were highly correlated to satisfaction. Gender, age, using period, visiting times after manufacturing denture were unrelated to satisfaction. But previous experience was related to denture satisfaction. Conclusion: Denture satisfaction was determined by a combination of various factors related to patients.

Analysis of Beginning Technology Teacher's Perception for Free Semester Program Class (자유학기제 수업에 대한 초임 기술 교사들의 인식 분석)

  • Kim, Seong-Il
    • 대한공업교육학회지
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    • v.42 no.1
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    • pp.125-139
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    • 2017
  • The purpose of this study was to provide a basic research data for increasing the satisfaction by analyzing perception of middle school beginning technology teachers 'technology home economics' class for free semester program. In order to investigate the class operation status, the survey questionnaires from 100 teachers were collected from middle school beginning teachers who teach technology home economics subject currently and analyzed by statistical program(SPSS ver.18). The main results of this study were as follows: First, there was no statistically significant difference to contents and satisfaction of lesson between teachers who experienced free semester program and not. In comparison of male teachers and female teachers, male teachers thought that free semester program was more helpful for student's 'career exploration' than female teachers, and there was statistically significant difference. Second, in the teacher's response according to have practice space and not, the satisfaction average of teachers who have practice space was higher(M=3.64) than those who have not at 'career exploration' and there was statistically significant difference satisfaction. Third, among the teachers who have experienced free semester program, male teachers were having more difficulty 'determining the assessment criteria' than the female teachers and there was statistically significant difference. Fourth, to improve the satisfaction of technical lesson, technology teachers asked to solve lack of practice material, increase of lesson-time, lack of practice space and lesson contents etc. Fifth, technology teachers asked free semester program seminars and information because free semester program lesson contents was given by internet and research groups of technology education.

Bioimpedence to Assess Breast Density as a Risk Factor for Breast Cancer in Adult Women and Adolescent Girls

  • Maskarinec, Gertraud;Morimoto, Yukiko;Laguana, Michelle B;Novotny, Rachel;Guerrero, Rachael T Leon
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.1
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    • pp.65-71
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    • 2016
  • Although high mammographic density is one of the strongest predictors of breast cancer risk, X-ray based mammography cannot be performed before the recommended screening age, especially not in adolescents and young women. Therefore, new techniques for breast density measurement are of interest. In this pilot study in Guam and Hawaii, we evaluated a radiation-free, bioimpedance device called Electrical Breast Densitometer$^{TM}$ (EBD; senoSENSE Medical Systems, Inc., Ontario, Canada) for measuring breast density in 95 women aged 31-82 years and 41 girls aged 8-18 years. Percent density (PD) was estimated in the women's most recent mammogram using a computer-assisted method. Correlation coefficients and linear regression were applied for statistical analysis. In adult women, mean EBD and PD values of the left and right breasts were $230{\pm}52$ and $226{\pm}50{\Omega}$ and $23.7{\pm}15.1$ and $24.2{\pm}15.2%$, respectively. The EBD measurements were inversely correlated with PD ($r_{Spearman}=-0.52$, p<0.0001); the correlation was stronger in Caucasians ($r_{Spearman}=-0.70$, p<0.0001) than Asians ($r_{Spearman}=-0.54$, p<0.01) and Native Hawaiian/Chamorro/Pacific Islanders ($r_{Spearman}=-0.34$, p=0.06). Using 4 categories of PD (<10, 10-25, 26-50, 51-75%), the respective mean EBD values were $256{\pm}32$, $249{\pm}41$, $202{\pm}46$, and $178{\pm}43{\Omega}$ (p<0.0001). In girls, the mean EBD values in the left and right breast were $148{\pm}40$ and $155{\pm}54{\Omega}$; EBD values decreased from Tanner stages 1 to 4 ($204{\pm}14$, $154{\pm}79$, $136{\pm}43$, and $119{\pm}16{\Omega}$ for stages 1-4, respectively) but were higher at Tanner stage 5 ($165{\pm}30{\Omega}$). With further development, this bioimpedance method may allow for investigations of breast development among adolescent, as well as assessment of breast cancer risk early in life and in populations without access to mammography.

Chinese Patients with Gastric Cancer Need Targeted Adjuvant Chemotherapy Schemes

  • Shi, Wen-Tao;Wei, Lei;Xiang, Jin;Su, Ke;Ding, Qiong;Tang, Meng-Jie;Li, Ji-Qiang;Guo, Yi;Wang, Pu;Zhang, Jing-Wei
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.10
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    • pp.5263-5272
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    • 2012
  • Background: Gastric cancer (GC) is one of the most common cancers in China. Adjuvant chemotherapy (AC) is a routine auxiliary treatment for GC recommended by the guidelines issued in 2011 by the Ministry of Health of the People's Republic of China, but the relevant credible consequences in China have been insufficient because of China's late start and ethical concerns. Methods: A series of databases, including Cochrane Library, MEDLINE, EMBASE, the Chinese database of the National Knowledge Infrastructure and the VIP database, were searched by 2 reviewers independently for studies investigating AC for GC through March 2012. The retrieved literature was screened according to the eligibility criteria. Results: A total of 35 randomized control trials (RCTs) were subjected to the final analysis, including 4,043 patients in treatment group and 3,884 in the control group, as well as 4 clinical-control trials (CCTs), which accessed the final analysis with 238 and 252 patients, respectively. AC reduced the risk of death as a protective treatment with statistical significance (HR=0.91, 95%CI: [0.85, 0.97], P=0.002), and it seemed more effective for Asian than non-Asian patients. The effects of AC were not influenced by the starting time (P>0.05). D2 lymphadenectomy-based chemotherapy was effective (HR=0.89, 95%CI: [0.80, 0.99], P=0.04). Oral S-1 40 mg/m2 after D2 lymphadenectomy might be a better choice for Asians with advanced GC and might result in a greater reduction of adverse events than in non-Asian patients. GRADE quality assessment determined that the strength of the evidence from foreign studies from Europe, the United States and Asian countries other than China was high, while it was moderate for Chinese studies. Conclusion: AC was effective or even curative in Chinese patients in general, although it is still necessary to optimize a targeted AC scheme for Chinese patients with GC.

The Application State of the Sunnybrook Facial Grading System for Facial Palsy Patients : A retrospective study (안면마비 환자에 대한 Sunnybrook Facial Grading System의 적용 실태 분석 : 후향적 관찰연구)

  • Han, Ji Sun;Kwon, Min Soo;Kim, Jung Hwan;Jo, Dae Hyun;Jo, Hee Jin;Choi, Ji Eun;Kim, Ji Hye;Kim, Hyun Ho;Lee, Sang Hoon;Park, Young Jae;Park, Young Bae
    • Journal of Acupuncture Research
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    • v.33 no.4
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    • pp.101-108
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    • 2016
  • Objectives : Among the assessment tools for evaluating facial function, the House-Brackmann scale is used as a standard tool, but it has some shortcomings. The Sunnybrook Facial Grading System can assess the after effects of facial palsy and facial movement by each part of the face. By understanding the application state of this Sunnybrook Facial Grading System, we intend to analyze the relationship between House-Brackmann scale score and Sunnybrook Facial Grading System score so that we can examine the advantages of the Sunnybrook Facial Grading System as a more accurate tool. Methods : We screened both inpatients and outpatients who visited the Facial Palsy Center at Kyung Hee University Hospital for Korean medical treatment and were evaluated with the Sunnybrook Facial Grading System from December 2015 to October 2016. A total of 159 out of 166 patients were studied, including basic characteristics and missing data. We used descriptive statistics for general features of patients and SPSS Ver.18 for statistical analysis. Results : House-Brackmann scale and Sunnybrook Facial Grading System have high negative correlation through Pearson Correlation Coefficient with a score of -0.884. Analyzing outlier data resulting from relation analysis between the House-Brackmann scale and the Sunnybrook Facial Grading System showed many outliers when the damaged state of each part of the face is different. Conclusion : Sunnybrook Facial Grading System can make up for faults of the House-Brackmann scale, which is inferior in accuracy when each damage status of each part of the face is different. Sunnybrook Facial Grading System performs a detailed assessment of facial function and sequelae of facial palsy easier than the House-Brackmann scale.

Estimation and assessment of long-term drought outlook information using the long-term forecasting data (장기예보자료를 활용한 장기 가뭄전망정보 산정 및 평가)

  • So, Jae-Min;Oh, Taesuk;Bae, Deg-Hyo
    • Journal of Korea Water Resources Association
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    • v.50 no.10
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    • pp.691-701
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    • 2017
  • The objective of this study is to evaluate the long-term drought outlook information based on long-term forecast data for the 2015 drought event. In order to estimate the Standardized Precipitation Index (SPI) for different durations (3-, 6-, 9-, 12-months), we used the observation precipitation of 59 Automated Synoptic Observing System (ASOS) sites, forecast and hindcast data of GloSea5. The Receiver Operating Characteristic (ROC) analysis and statistical analysis (Correlation Coefficient, CC; Root Mean Square Error, RMSE) were used to evaluate the utilization of drought outlook information for the forecast lead-times (1~6months). As a result of ROC analysis, ROC scores of SPI(3), SPI(6), SPI(9) and SPI(12) were estimated to be over 0.70 until the 2-, 3-, 4- and 5-months. The CC and RMSE values of SPI(3), SPI(6), SPI(9) and SPI(12) for forecast lead-time were estimated as (0.60, 0.87), (0.72, 0.95), (0.75, 0.95) and (0.77, 0.89) until the 2-, 4-, 5- and 6-months respectively.