• Title/Summary/Keyword: consistency tests

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A Multi-Period Input DEA Model with Consistent Time Lag Effects (일관된 지연 효과를 고려한 다기간 DEA 모형)

  • Jeong, Byungho;Zhang, Yanshuang;Lee, Taehan
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.42 no.3
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    • pp.8-14
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    • 2019
  • Most of the data envelopment analysis (DEA) models evaluate the relative efficiency of a decision making unit (DMU) based on the assumption that inputs in a specific period are consumed to produce the output in the same period of time. However, there may be some time lag between the consumption of input resources and the production of outputs. A few models to handle the concept of the time lag effect have been proposed. This paper suggests a new multi-period input DEA model considering the consistent time lag effects. Consistency of time lag effect means that the time delay for the same input factor or output factor are consistent throughout the periods. It is more realistic than the time lag effect for the same output or input factor can vary over the periods. The suggested model is an output-oriented model in order to adopt the consistent time lag effect. We analyze the results of the suggested model and the existing multi period input model with a sample data set from a long-term national research and development program in Korea. We show that the suggested model may have the better discrimination power than existing model while the ranking of DMUs is not different by two nonparametric tests.

Effect of palm oil on the basic geotechnical properties of kaolin

  • Sriraam, Anirudh Subramanya;Raghunandan, Mavinakere Eshwaraiah;Ti, Tey Beng;Kodikara, Jayantha
    • Geomechanics and Engineering
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    • v.18 no.2
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    • pp.179-188
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    • 2019
  • This paper presents an experimental study to evaluate the effect of palm oil on the selected basic physical-chemical and geotechnical properties of kaolin. The experimental findings are further compared with literature outcomes investigating similar properties of fine grained soils subjected to contamination by different types of oils. To this end, palm oil was mixed with oven dried kaolin samples-aiding oil's interaction (coating) with dry particles first, in anticipation to emphasize the effect of oil on the properties of kaolin, which would be difficult to achieve otherwise. Oil content was limited to 40% by dry weight of kaolin, supplemented at intervals of 10% from clean kaolin samples. Observations highlight physical particle-to-particle bonding resulting in the formation of pseudo-silt sized clusters due to palm oil's interaction as evinced in the particle size distribution and SEM micrographs. These clusters, aided by water repellency property of the oil coating the kaolin particles, was analyzed to show notable variations in kaolin's consistency-measured as liquid and plastic limits. Furthermore, results from compaction tests indicates contribution of oil's viscosity on the compaction behavior of kaolin - showing decrease in the maximum dry unit weight (${\gamma}_{d,max}$) and optimum moisture content ($w_{opt}$) values with increasing oil contents, while their decrease rates were directly and inversely proportional in ${\gamma}_{d,max}$ and $w_{opt}$ values with oil contents respectively. Comparative study in similar terms, also validates this lower and higher decrease rates in ${\gamma}_{d,max}$ and $w_{opt}$ values of the fine grained soils respectively, when subjected to contamination by oil with higher viscosity.

Validation of Test Methods for Chloride Penetration Durability of Alkali Activated Slag (알칼리 활성 슬래그의 염해 내구성 평가 시험 방법 유효성)

  • Lim, Min-Hyuk;Lee, Do-Keun;Shin, Kyung-Joon;Song, Keum-Il;Song, Jin-Kyu
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.7 no.1
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    • pp.1-7
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    • 2019
  • Recently, studies on alkali activated slag(AAS) binders that do not use cement have been actively conducted. It is known that AAS concrete is highly resistant to chloride damage based on the test method used for ordinary concrete. However, it is fully not understood whether the test method used for concrete can be applied to AAS mixtures. Therefore, in this study, we verified the consistency of NT Build 492 and ASTM C 1202 test methods by applying various experimental variables. According to the experimental results, the two tests yielded opposite results. Therefore, the chloride durability of AAS mortar can be different depending on the evaluation method.

The study of development on CFT(Cognitive Function Test) in mild cognitive impairment (경도인지장애 대상자의 인지기능평가도구(CFT) 개발 연구)

  • Lee, Seon-Myeong;Ju, Eun-U;Song, Jin-Seok;Park, Sin-Jun;Kim, Heon-Mo;Jeong, Eun-Seung;Im, Chae-Ho;Son, Seong-Min;Ha, Hye-Jeong
    • Journal of Korean Clinical Health Science
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    • v.8 no.2
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    • pp.1426-1435
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    • 2020
  • Objective: This study aims to develop CFT, a screening test for dementia that can be conducted on patients with mild cognitive impairment or early dementia. Methods: This study was conducted on therapists working at occupational therapy hospital in Gyeongsangnam-do. The data collection period is two months from July to September 2020, and the research participants were briefed on the purpose, significance, and anonymity of the research in consideration of ethical issues. A total of 33 copies of the data were finally analyzed, excluding those containing insufficient answers and errors, by distributing 40 copies of the data. SPSS Data Access pack 8.0 was used for data analysis, Cronbach's α value was evaluated for internal consistency reliability of each item, and Pearson Correlation coeffient between the lower scales of the assessment tool was measured. Results: The Cronbach's α value of the CFT was shown as .892 and the reliability of the assessment paper was shown to be quite high. The Cronbach's α value for each item in the cognitive assessment tool was the highest at .899 in the subtraction item, with exercise control (mook Chi Pa) at 888, visual memory, plus .887. The correlation of each item of cognitive assessment tools was found to be most correlated with the number of sustained concentrates and word2 to .934; in the stop word-numeric item and visual memory to be .85; and in the addition to the auditory memory item .739. Conclusion: Therefore, this study developed cognitive evaluation tools that can distinguish the diversity and cognitive level of screening tests and clarify standards, which are different from the existing dementia screening tools in Korea. Furthermore, the cognitive assessment tools of this study can be verified by applying them to patients with mild cognitive impairment and early dementia, and the criteria for generalization can be established.

Topographical measurement of the attachments of the central band of the interosseous membrane on interosseous crests of the radius and ulna

  • Jang, Suk-Hwan;Kim, Kyung-Whan;Jang, Hyo Seok;Kim, Yeong-Seok;Kim, Hojin;Kim, Youngbok
    • Clinics in Shoulder and Elbow
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    • v.24 no.4
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    • pp.253-260
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    • 2021
  • Background: To suggest a reasonable isometric point based on the anatomical consistency of interosseous membrane (IOM) attachment in association with topographic characteristics of the interosseous crests, the footprints of the central band (CB) of the IOM on the radial and ulnar interosseous crests (RIC and UIC) were measured. Methods: We measured the distance from the CB footprints from each apex of both interosseous crests in 14 cadavers and the angles between the forearm axis of rotation (AOR) and the distal slopes of the RIC and UIC in 33 volunteers. Results: The CB footprints lay on the downslope of both interosseous crests with its upper margin on average 3-mm proximal from the RIC's apex consistently in the radial length, showing normality (p>0.05), and on average 16-mm distal from the UIC's apex on the ulna without satisfying normality (p<0.05). The average angle between the UIC's distal slope and the AOR was 1.3°, and the RIC's distal slope to the AOR was 14.0°, satisfying the normality tests (p>0.05), and there was no side-to-side difference in both forearms (p<0.05). Conclusions: The CB attached to the downslope just distal to the RIC's apex constrains the radius to the UIC that coincides with the AOR of the forearm circumduction, maintaining itself both isometrically and isotonically.

Effects of Electrical Stimulation on Patients with Non-Specific Low Back Pain : A Meta-Analysis of Domestic Database (비특이적 만성 허리통증 환자에 대한 전기자극의 효과 : 국내 데이터베이스의 메타분석)

  • Lee, Jeong-Woo;Cho, Sung-Hyoun
    • Journal of The Korean Society of Integrative Medicine
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    • v.10 no.3
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    • pp.37-52
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    • 2022
  • Purpose : The purpose of this meta-analysis was to evaluate the effects of electrical stimulation on patients with non-specific low back pain. Methods : Domestic databases were gathered from studies that conducted clinical trials associated with electrical stimulation and its impact on pain of non-specific low back patients. A total of 681 studies were identified, with 12 studies satisfying the inclusion data. The studies consisted of patient, intervention, comparison, outcome, and study design (PICO-SD). The search outcomes were items associated with low back pain. Cochrane risk of bias 2 (RoB 2) was used to evaluate the quality of 12 randomized controlled trials. Effect sizes (Hedges's g) in this study were computed as the corrected standard mean difference (SMD). A random-effect model was used to analyze the effect size because of the high heterogeneity among the studies. Egger's regression and 'trim-and-fill' tests were carried out to analyze the publication bias. Cumulative meta-analysis and sensitivity analysis were conducted to analyze the effect according to the sample size and the consistency of the effect size. Results : The following factors had a large overall effect size (Hedges's g=1.28, 95 % CI=.20~2.36) involving electrical stimulation on non-specific low back pain. The subgroup analysis all showed a statistical difference in the types of study design, electrical stimulation, and assessment tool. No statistically significant difference was found in the meta-regression analysis. Publican bias was found in the data. Conclusion : The findings in this study indicate that electrical stimulation interventions have a positive effect on patients with non-specific low back pain. However, due to the low quality of studies and publication bias, the results of our study should be interpreted cautiously.

Development of a Creativity Test for Children from 4 to 7 years (유아와 초등학교 저학년 아동을 위한 창의성 검사 도구 개발)

  • Kim, Ho
    • Journal of Creative Information Culture
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    • v.5 no.3
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    • pp.265-273
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    • 2019
  • This study develops and examines the validity of a Creativity Test for children from of 4 to 7. 47 items were constructed through the validity of the literature and expert's content validity. The results of this study consisted of 22 items with three factors. These factors are flow and independence, expansion of thinking, curiosity and openness. The tests scale was examined about item's response distribution, item's discrimination, and construct validity and internal consistency reliability, and it was adoptable. It can be concluded that the test tool developed in this study is suitable for measuring the creativity of Korean children from 4 to 7 years in a simple manner, and it measures relatively well the cognitive and affective characteristics of creativity. Creativity test tool for children from 4 to 7 years in this study will contribute to the active progress of research on creativity for young children and elementary school children.

Determination of homogeneity index of cementitious composites produced with eps beads by image processing techniques

  • Comak, Bekir;Aykanat, Batuhan;Bideci, Ozlem Salli;Bideci, Alper
    • Computers and Concrete
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    • v.29 no.2
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    • pp.107-115
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    • 2022
  • With the improvements in computer technologies, utilization of image processing techniques has increased in many areas (such as medicine, defence industry, other industries etc.) Many different image processing techniques are used for surface analysis, detection of manufacturing defects, and determination of physical and mechanical characteristics of composite materials. In this study, cementitious composites were obtained by addition of Grounded Granulated Blast-Furnace Slag (GGBFS), Styrene Butadiene polymer (SBR), and Grounded Granulated Blast-Furnace Slag and Styrene Butadiene polymer together (GGBFS+SBR). Expanded Polystyrene (EPS) beads were added to these cementitious composites in different ratios (20%, 40% and 60%). The mechanical and physical characteristics of the composites were determined, and homogeneity indexes of the composites were determined by image processing techniques to determine EPS distribution forms in them. Physical and mechanical characteristics of the produced samples were obtained by applying consistency, density, water absorption, compressive strength (7 and 28 days), flexural strength (7 and 28 days) and tensile splitting strength (7 and 28 days) tests on them. Also, visual examination by using digital microscope, and image analysis by using image processing techniques with open source coded ImageJ program were performed. As a result of the study, it is determined that GGBFS and SBR addition strengthens the adhesion sites formed as it increases the adhesion power of the mixture and helps to get rid of the segregation problem caused by EPS. As a result of the image processing analysis it is demonstrated that GGBFS and SBR addition has positive contribution on homogeneity index.

The Reliability and Validity of a Portable Hand-held Spirometer for the Measurement of Various Lung Functions in Healthy Adults

  • Merve Nur Uygun;Jun-Min Ann;Byeong-Hyeon Woo;Hyeon-Myeong Park;Ha-Im Kim;Dae-Sung Park;In-Beom Jeong
    • Physical Therapy Rehabilitation Science
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    • v.13 no.2
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    • pp.179-186
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    • 2024
  • Objective: This study aims to assess the reliability and validity of the new hand-held spirometer as a potential substitute for traditional pulmonary function testing (PFT) devices. Design: Cross-sectional study. Methods: In this study, thirty healthy adults underwent spirometry using both the new hand-held spirometer and the MIR spirometer, which is a standard PFT device. Parameters including peak expiratory flow (PEF), forced expiratory volume in one second (FEV1), and forced vital capacity (FVC) were measured and analyzed for validity and reliability. Inter-rater reliability and validity were evaluated through 95% limits of agreement (LOA) and intraclass correlation coefficients (ICC). Statistical analyses, including the Bland-Altman plots and the ICC, were utilized to assess agreement between the two devices. Results: The new hand-held spirometer exhibited a good agreement with intra-class coefficient (ICC [2,1]) ranging 0.762 to 0.956 and 95% LOA of -1.94 to 1.80 when compared with MIR. The test-retest reliability of the hand-held spirometer analyzed using - ICC [2,1] demonstrated a good level of consistency (ICC [2,1] =0.849-0.934). Conclusions: In conclusion, the study aimed to assess the potential of the new hand-held spirometer as a viable alternative to traditional PFT devices, with a specific focus on its reliability and validity in spirometric measurements. The new hand-held spirometer exhibited good test-retest reliability across all measured variables, suggesting its potential as a valid and reliable tool for simultaneous PFT measurements.

The Effect on The Result, in Case of the In-vitro Test Performance after an Imaging Test (핵의학 영상검사 후 시행된 핵의학 검체검사에서의 영향)

  • Moon, Ki Choon;Kwon, Won Hyun;Kim, Jung In;Lee, In Won
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.149-152
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    • 2014
  • Purpose: At our hospital blood is collected from a patient before an imaging test, with the concern of any effect possible when a nuclear medicine imaging test and an in-vitro test are carried out at the same time. However, occasionally, the blood collection is performed after an imaging test, with the reasons that the patient is not properly guided or the patient doesn't follow the guide correctly. In that case, we prefer to gather blood again after a few days. The purpose of this study is not only to see whether there is any effect of an imaging test on the result of the in-vitro test performed with the blood collected after the imaging test, but also to study how many days waiting after each test is appropriate to take a blood sample, if the effect exists. Materials and Methods: From September to October 2013, blood were collected from 13 patients in our hospital regardless of age and sex each time before and after the injection of the radioactive isotope from the tests : PET-CT, Gated Myocardial SPECT, and DTPA GFR Scan. Considering a half-life, AFP, CA19-9, CEA, TSH, and T3 were carried out right after the blood collection. In case of an iodine therapy, blood were taken each time before and after taking radioactive iodine, and, after AFP, CA19-9, and CEA, the difference between them in consistency and in cpm were compared. Results: With 10 patients after the imaging tests and 3 patients after the iodine therapy, their serum cpm was over 10,000. Over time, the cpm decreased in accordance with the half-life ($^{18}F$ 110minutes, $^{99}mTc$ 6hours, $^{201}Tl$ 72hours, $^{131}I$ 7days). Between the two cases, one before and the other after the injection of the radioactive isotope, the cpm and the results of AFP, CA19-9, CEA, TSH, and T3 from three patients each test, PET-CT, Gated Myocardial SPECT, and DTPA GFR Scan, were very similar. In addition, in case of an iodine therapy, there was also not a meaningful difference in the cpm and the results of AFP, CA19-9, and CEA, from three patients in an iodine therapy, between the two cases, one before and the other after taking the radioactive iodine. Conclusion: In case a blood collection was performed after the imaging test which required a radioactive isotope injection, the cpm increased, differently according to the kind of the radioactive isotope. However, the results of the in-vitro tests like AFP, CA19-9, CEA, TSH, T3, etc were nearly not affected. As the result, it's considered that there will not be any significant effect also from other tests, as the result from the performed seven tests.

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