• Title/Summary/Keyword: loss index

Search Result 1,421, Processing Time 0.039 seconds

Los Angeles Abrasion Test for Estimating Engineering Index on the Sedimentary Rocks of Kyeongsang Basin (퇴적암의 공학지수를 추정하기 위한 L. A. 마모율 시험)

  • Min, Tuk-Ki;Moon, Jong-Kyu;Lee, Sang-Il
    • Journal of the Korean Geotechnical Society
    • /
    • v.23 no.11
    • /
    • pp.15-26
    • /
    • 2007
  • Los Angeles abrasion loss test has usally been applied to the quarry for the purpose of aggregate hardness estimation. 324 blocks from 25 sites of Kyeongsang basin samples of sedimentary rock were examined and tested in laboratary. This paper found that L. A. abrasion loss test is a good method to estimate engineering index such as uniaxial compressive strength, elastic modulus, indirect tensile strength, point load strength index, Schmidt hammer rebound value of sedimentary rocks with high correlation factor. Engineers will prefer L. A. abrasion loss test to the other one for design and construction as this method is quick and easy.

A MW-Mvar Investment Technique Focused on System Loss Minimization

  • Eom, Jae-Sun;Lee, Sang-Joong;Kim, Kern-Jong
    • Journal of KIEE
    • /
    • v.11 no.1
    • /
    • pp.51-54
    • /
    • 2001
  • In this paper, a MW-Mvar investment technique focused on minimizing the system loss is presented. An optimization technique, in which the system loss is defined as the objective function and the power flow equations as the constraints, is introduced to obtain the Lagrangian multipliers λP and λQ. The Lagrangian multipliers imply the variation of the system loss with respect to incremental bus power and are used as MW-Mvar investment indices for minimizing the system loss. ΔP MW and ΔQ Mvar are invested, step by step, by the priority of λP and λQ index given for each bus. Derivation of the index uses the information from normal power flow calculation.

  • PDF

Diet Quality Index-International Score is Correlated with Weight Loss in Female College Students on a Weight Management Program (체중관리 영양교육에 참여한 여대생의 Diet Quality Index-International (DQI-I)점수와 체중감소와의 상관성)

  • Yun, Hee-Kyung;Kim, Hye-Sook;Chang, Nam-Soo
    • Journal of Nutrition and Health
    • /
    • v.42 no.5
    • /
    • pp.453-463
    • /
    • 2009
  • This study was to evaluate the effectiveness of the weight control program for female college students. The program was composed of diet and behavioral modifications for 8 weeks. A total of 78 participants enrolled the weight control program. Upon completion of the program, 53 participants experienced weight loss and 25 did not. The intakes of carbohydrate and fat were significantly decreased in both groups. However, the total diet quality index-international (DQII) scores as well as individual scores such as variety scores for protein source and adequacy scores for vegetable, fiber, calcium and vitamin C and moderation scores for empty calorie food were increased significantly in weight loss group only. In the weight loss group, weight, BMI, body fat, percent body fat and waist-hip ratio were decreased significantly. In addition, compared to the weight gain group, the weight loss group had higher changes in weight (weight loss group: -2.6% vs weight gain group: 1.5%, p < 0.001), body fat (-6.0% vs 0.0%, p < 0.001), percent body fat (-3.1% vs -0.3%, p < 0.001), waist-hip ratio (-1.0% vs 0.5%, p < 0.001) and BMI (-2.6% vs 1.3%, p < 0.01). There was no difference in blood profiles between the two groups. The changes in DQI-I scores were significantly correlated with the changes in body weight (r = -0.239, p < 0.05) and BMI (r = -0.224, p < 0.05), indicating that effective nutrition education could help improve diet quality leading to successful weight management among female college students.

Determination of Permissible Shear Stresses on Vegetation Mats by Soil Loss Evaluation (토양 손실 평가에 의한 식생매트의 허용 소류력 결정)

  • Lee, Du Han;Rhee, Dong Sop;Kim, Myounghwan
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.11
    • /
    • pp.5956-5963
    • /
    • 2013
  • By the activation of environment-friendly river works, application of vegetation mats is increasing, however, evaluation techniques for hydraulic stability of vegetation mats are not presented. This study is conducted to develop the objective test method for vegetation mats. Two kind of vegetation mats are tested by the real scale experiments, and hydraulic quantities are measured and analyzed to evaluate acting shear stresses. To evaluate soil loss, Terrestrial 3D LiDAR measurement is conducted and soil loss index are calculated from changes of bed elevation. Quantified evaluation for permissible shear stresses is conducted by graphical method for acting shear stresses and soil loss index. By the results of precision survey, changes of sub soil are limited to local range in stable cases and relatively large changes of sub soil which is similar to natural river bed are detected in unstable cases. From the study, evaluation of permissible shear stresses by ASTM D 6040 is avaliable in the failure mechanism and failure criteria by soil loss index.

Temperature effect on wireless impedance monitoring in tendon anchorage of prestressed concrete girder

  • Park, Jae-Hyung;Huynh, Thanh-Canh;Kim, Jeong-Tae
    • Smart Structures and Systems
    • /
    • v.15 no.4
    • /
    • pp.1159-1175
    • /
    • 2015
  • In this study, the effect of temperature variation on the wireless impedance monitoring is analyzed for the tendon-anchorage connection of the prestressed concrete girder. Firstly, three impedance features, which are peak frequency, root mean square deviation (RMSD) index, and correlation coefficient (CC) index, are selected to estimate the effects of temperature variation and prestress-loss on impedance signatures. Secondly, wireless impedance tests are performed on the tendon-anchorage connection for which a series of temperature variation and prestress-loss events are simulated. Thirdly, the effect of temperature variation on impedance signatures measured from the tendon-anchorage connection is estimated by the three impedance features. Finally, the effect of prestress-loss on impedance signatures is also estimated by the three impedance features. The relative effects of temperature variation and prestress-loss are comparatively examined.

The Reliability and Validity of Korean Version of the Wheelchair User's Shoulder Pain Index in Wheelchair Users (휠체어 사용자를 위한 한국어판 WUSPI의 신뢰도와 타당도)

  • Park, Ji-Yeon;Cho, Sang-Hyun
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.8 no.4
    • /
    • pp.573-582
    • /
    • 2013
  • PURPOSE: The purpose of this study was to establish the reliability and validity of the Wheelchair User's Shoulder Pain Index (WUSPI), which was translated into Korean for long-term wheelchair users. This index measured 15 functional activities, including transfer, self-care, wheelchair mobility and general activities. METHODS: To assess test-retest reliability, 23 long-term wheelchair users completed this self-administered index twice within the same day. Reliability was determined by the intraclass correlation coefficient (ICC), and Cronbach's alpha was used to measure internal consistency. To examine concurrent validity, 21 long-term wheelchair users completed the questionnaire, and we examined the correlation between the index score and the shoulder range of motion measurements. RESULT: The results showed that the intraclass correlation for test-retest reliability of the total index score ranging from .88 to .99 was good to excellent. Additionally, Cronbach's alpha was .96. The internal consistency indicated excellent. Concurrent validity showed negative correlations of total index score to range of motion measurements of shoulder flexion (rho=-.58), extension (rho=-.09), abduction (rho=-.59), external rotation (rho=-.07) and internal rotation (rho=-.3), suggesting a relationship of total index score to loss of shoulder range of motion. CONCLUSION: The Korean WUSPI shows not only high reliability and internal consistency, but also concurrent validity with loss of shoulder flexion and abduction.

Propagation loss measurement of silica slab waveguide using index matching fluid (굴절률 정합액을 이용한 실리카 슬랩도파로의 전송손실 측정)

  • 성희경;박상호;신장욱;심재기
    • Korean Journal of Optics and Photonics
    • /
    • v.10 no.2
    • /
    • pp.174-177
    • /
    • 1999
  • The propagation loss of silica slab waveguides were measured by immersing slab waveguides into a index matching liqiud. Index matching liqiud was used for out-coupling the light from arbitrary points of slab waveguide. The measured value of propagation loss are 0.04 dB/cm and 0.09 dB at 1300 nm and 633 nm respectively.

  • PDF

A Study on Voltage Stability Improvement by the Efficient Network Reconfiguration Algorithm

  • Kim, Byung-Seop;Shin, Joong-Rin;Park, Jong-Bae;Shin, Yong-Hak
    • KIEE International Transactions on Power Engineering
    • /
    • v.4A no.2
    • /
    • pp.58-68
    • /
    • 2004
  • This paper presents an optimal routing algorithm (ORA) for maximizing voltage stability as well as for minimizing power loss in radial power systems. In the proposed ORA, a novel voltage stability index (VSI) for real-time assessment is newly introduced based on the conventional critical transmission path framework. In addition, the suggested algorithm can automatically detect the critical transmission paths resulting in voltage collapse when additional real or reactive loads are added. To implement an effective ORA, we have developed an improved branch exchange (IBE) method based on a loss calculation index and tie-branch power flow equations, which are suggested for real-time applications. The proposed algorithm has been tested with IEEE test systems as well as a large-scale power system in Korea to demonstrate its effectiveness and efficiency.

Simultaneous Measurement of Temperature and Refractive Index of a Medium Using by a Side-Polished Fiber Containing a Fiber Bragg Grating (광섬유 브래그 격자가 포함된 측면 연마된 광섬유를 이용한 매질의 온도와 굴절률 동시 측정)

  • Kim, Kwang Taek
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.28 no.8
    • /
    • pp.513-517
    • /
    • 2015
  • We proposed and demonstrated a simultaneous measurement method to detect the refractive index and temperature of a medium using a side-polished fiber involving FBG (fiber Bragg grating). The temperature of a medium was obtained by using the Bragg wavelength shift of FBG, while the refractive index of medium were calculated by using the transmission loss. The Bragg wavelength is independent on the refractive index of the covering medium placed on surface of side-polished fiber, while the transmission loss at off-Bragg wavelength highly depends on the environmental temperature because of thermo-optic effect of the medium.

Real-time Monitoring of Glucose Using a Differential Refractive Index Detector (시차 굴절률 측정에 의한 실시간 글루코오스 모니터링)

  • 정진갑;이명희;최은경
    • Textile Coloration and Finishing
    • /
    • v.16 no.2
    • /
    • pp.47-51
    • /
    • 2004
  • A differential refractive index detector was used for monitoring glucose contents in textile processing solutions. The sensitivity of the device was high enough to measure 0.05% aqueous glucose solution that could not be measured by normal refractive index measurement. The device was set to monitor glucose concentration continuously in real time by measuring differential refractive index and calibrated by standard glucose solutions in a range of 0.1 to 1.0%. The possibility of industrial application of the device was demonstrated by real-time monitoring of glucose concentration in textile processing solutions such as desizing bath and cellulase treatment bath. Both of solutions contained glucose as a major degraded product. The device would be able to control the weight loss of cellulosic fiber during cellulase treatment since the amount of degraded products in a processing bath is proportional to its weight loss.