• Title, Summary, Keyword: Loss reduction

Search Result 2,318, Processing Time 0.06 seconds

A Study on the Loss Reduction Method of Reinforcing Bar through Case Study

  • Park, U-Yeol;Jung, Hyeon-Ok;Kang, Tai-Kyung;Cho, Hun-Hee
    • Journal of the Korea Institute of Building Construction
    • /
    • v.10 no.4
    • /
    • pp.123-132
    • /
    • 2010
  • Rebar work accounts for approximately 30% of the total construction costs for rebars and concrete. Recently, the high rising prices of rebars have become one of the principle factors of rising construction costs. Therefore, construction companies are putting much effort into loss reduction of rebars. Consequently, in this study, we wished to present loss reduction methods of rebars before the preparation of the placing drawings. To devise such methods, we collected previous case studies and analyzed methods that were applied for loss reduction. As a result of the analysis, we were able to find the following methods for loss reduction of rebars: method of reducing the number of splices at the mat foundation, method of reducing splice length at the internal columns or walls of the underground parking lot, method of reducing cap-ties of internal beams of basement floors excluding perimeter beams, and method of reducing anchorage length at the internal column or wall of the underground parking lot. Based on those analysis results, we presented our own loss reduction methods of rebars. Applying our methods resulted in considerable loss reduction.

A Study on the Inherent Defects in the eUCP Article 11 & Implication for the Revision (eUCP 11조의 잠재적 하자의 규명과 합리적 개정방안의 모색)

  • Kim, Ki-Sun
    • The Korean Research Institute of International Commerce and Law
    • /
    • v.35
    • /
    • pp.41-69
    • /
    • 2007
  • This study analyzes some important implications for the forthcoming revision of eUCP through the methodology of expected utility maximization theory. The overall results are as follows. First, beneficiary with an initial wealth has a risk-averse utility in traditional letter of credit transaction, and he would be more risk-averse in eUCP transaction. Secondly, the beneficiary who has risk-averse utility will pay for the risk premium to reduce the risk of corruption of an electronic record by means of cost of loss reduction activities. Thirdly, the cost of loss reduction activities is represented by a convex cost function, Fourthly, a risk averse beneficiary pursues loss reducing activities to the point where the expected marginal product of loss reduction is less than its marginal cost. Fifthly, a more risk-averse eUCP beneficiary will always select a higher level of loss reduction as long as the effectiveness of loss reduction is certain. Sixthly, when the effectiveness of loss reduction is uncertain, the more risk-averse eUCP beneficiary does not necessarily choose a higher level of loss reducing activities. Finally, it would be more reasonable that eUCP Article 11 should protect eUCP beneficiary who pursues a higher level of loss reducing activities.

  • PDF

A Study on Distribution Network Reconfiguration for Loss Reduction (손실감소를 위한 배전계통 재구성에 관한 연구)

  • Kim, S.H.;Choi, B.Y.;Cho, S.H.;Son, I.B.;Moon, Y.H.
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.686-688
    • /
    • 1996
  • Network reconfiguration is performed by opening/closing two types of switches, tie and sectionalizing switches. A whole feeder, or part of a feeder, may be served from another feeder by closing a tie switch linking the two while an appropriate sectionalizing switch must be opened to maintain radial structures. In loss reduction, the problem is to identify tie and sectionalizing switches that should be closed and opened, respectively, to achieve a maximum loss reduction. In this paper, it is introduced to propose the reconfiguration plan for loss reduction by using the Civanlar's loss reduction formular.

  • PDF

Loss Reduction in Heavy Loaded Distribution Networks Using Cyclic Sub Tree Search (순환적 부분트리 탐색법을 이용한 중부하 배전계통의 손실최소화)

  • Choi, Sang-Yule;Shin, Myong-Chul
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.50 no.5
    • /
    • pp.241-247
    • /
    • 2001
  • Network reconfiguration in distribution systems is realized by changing the status of sectionalizing switches, and is usually done for loss reduction of load balancing in the system. This paper presents an effective heuristic based switching scheme to solve the distribution feeder loss reduction problem. The proposed algorithm consists of two parts. One is to set up a decision tree to represent the various switching operations available. Another is to apply a proposed technique called cyclic best first search. the proposed algorithm identify the most effective the set of switch status configuration of distribution system for loss reduction. To demonstrate the validity of the proposed algorithm, numerical calculations are carried out the 32, 69 bus system models.

  • PDF

Noise Reduction of PDP TV Cooling Fan System through Parameter Analysis (인자 분석을 통한 플라즈마 디스플레이 패널(Plasma Display Panel) 텔레비전에서의 냉각 홴 시스템 소음 저감)

  • Kim, Kyu-Young;Choi, Min-Goo;Lee, Duck-Joo
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.16 no.2
    • /
    • pp.107-114
    • /
    • 2006
  • The present experimental study deals with noise reduction and improvements in cooling performance in a plasma display panel (PDP) television (TV). The main ideas of the fan system noise reduction are maintenance of uniform inflow condition and reduction of the system loss, ${\Delta}P.$ The discrete noise is mainly related with the inflow condition therefore removing the structure which distorts inflow makes the discrete noise reduction. The broadband noise in PDP TV is related with the system losses which result from the presence of the fan downstream obstacle, PDP rear case. Through the modification of the distance and preventing the leakage flow between the fan and rear case, we can obtain the system loss and broadband noise reduction. Additionally we can reduce fan rotating speed because of increased flow rate which obtains from the reduction of system loss (resistance). Finally, 4.2 dB(A) noise reduction and $10\%$ increase in flow rate are achieved. From these results, we show that the reduction of system loss is the most effective way of the fan system noise reduction.

Evaluation of Tip Leakage Loss and Reduction of Efficiency of Axial Turbomachinery Using Numerical Calculation (수치계산에 의한 축류터보기계의 회전차 익말단의 누설손실과 효율저하에 대한 평가)

  • Ro, Soo-Hyuk;Cho, Kang-Rae
    • The KSFM Journal of Fluid Machinery
    • /
    • v.2 no.1
    • /
    • pp.73-80
    • /
    • 1999
  • Leakage vortices formed new blade tip causes an increase of total pressure loss near the casing endwall region and as a result, the efficiency of rotor decreases. The reduction of rotor efficiency is related to the size of the tip clearance. In this study, the three-dimensional flowfields in an axial flow rotor were calculated by varying the tip clearance under various flow rates, and the numerical results were compared with experimental ones. The effects of tip clearance and attack angle on the leakage vortex and overall performance, and the loss distributions were investigated through numerical calculations. In this study, tip leakage flow rate and total pressure loss by tip clearance were evaluated using numerical results and approximate equations were presented to evaluate the reduction of rotor efficiency by tip leakage flow.

  • PDF

A Study on CIETEC Arbitration Case for the Relationship between Damages and Reduction under CISG (CISG상 손해배상과 대금감액의 관계에 관한 중국 CIETAC의 중재사례 연구)

  • Song, Soo-Ryun
    • The Korean Research Institute of International Commerce and Law
    • /
    • v.51
    • /
    • pp.133-158
    • /
    • 2011
  • The purpose of this study is to analyze one of CIETEC(China International Economic and Trade Arbitration Commission) Award on the dispute arising from Cotton Sale Contact which deals with damages and reduction of the price. Especially this case focused on the effect of reduction of the price to damages. The purpose of damages is to place the aggrieved party in as good a position as if the other party had properly performed the contract. So court costs and attorney's fee should be regarded as the loss, because these are caused by consequence of the breach which is recoverable. With the same reason, overpaid taxes should also regard as the loss. It is not impossible, however, to claim both damages and reduction of the price for same loss at the same time. It means buyer could not claim damages for the same loss, once he already claimed reduction of the price. So Korean companies should consider which remedy is proper to himself under the circumstances. He should choose reduction of the price when market price is down. In case of rising market price, he should consider follows: first, it is better to choose damages based on current price(Art.76), if upswing of non-conformity price is higher then upswing of market price. Second, it is better to choose general rule for measuring damages(Art.74), if upswing of market price is higher then upswing of non-conformity price.

  • PDF

Reduction Loss after Extension Block Kirschner Wire Fixation for Treatment of Bony Mallet Finger (골성 추지 신전제한 K 강선 고정술 시행 후 정복소실)

  • Kim, Byungsung;Nho, Jae-Hwi;Jung, Ki Jin;Yun, Keonhee;Park, Eunseok;Park, Sungyong
    • Archives of Hand and Microsurgery
    • /
    • v.23 no.4
    • /
    • pp.239-247
    • /
    • 2018
  • Purpose: We investigated occurrence of reduction loss after extension block (EB) Kirschner wire fixation or additional interfragmentary fixation (AIF) and clinical results including extension lag of the distal interphalangeal joint for treating bony mallet finger. Methods: Forty-six patients were included with a mean follow-up of 28 months (range, 12-54 months). Twenty-seven patients were treated with EB K-wire fixation (Group A) while 19 patients were treated with AIF (Group B). We checked radiologic factors, such as amount of articular involvement, volar subluxation, mallet fragment angle, reduction loss, range of motion including extension lag, and functional outcomes using Crawford's criteria. Results: Reduction loss occurred in eight patients (17%). Differences in mean extension lag, age, preoperative volar subluxation and mallet fragment angle between patients with reduction loss and those with reduction maintaining were significant. However, there were no significant differences in gender, hand dominance, amount of articular involvement, AIF, or further flexion between reduction loss and reduction maintaining. As for patterns of displacement, there was a significant relationship between gap or step-off and extension lag. Using Crawford's evaluation criteria, functional outcomes were excellent in 31, good in 10, fair in 3, and poor in 2 patients. Conclusion: Reduction loss should be careful in older age, smaller mallet fragment angle and preoperative volar subluxation.

Opposition Based Differential Evolution Algorithm for Capacitor Placement on Radial Distribution System

  • Muthukumar, R.;Thanushkodi, K.
    • Journal of Electrical Engineering and Technology
    • /
    • v.9 no.1
    • /
    • pp.45-51
    • /
    • 2014
  • Distribution system is a critical link between customer and utility. The control of power loss is the main factor which decides the performance of the distribution system. There are two methods such as (i) distribution system reconfiguration and (ii) inclusion of capacitor banks, used for controlling the real power loss. Considering the improvement in voltage profile with the power loss reduction, later method produces better performance than former method. This paper presents an advanced evolutionary algorithm for capacitor inclusion for loss reduction. The conventional sensitivity analysis is used to find the optimal location for the capacitors. In order to achieve a better approximation for the current candidate solution, Opposition based Differential Evolution (ODE) is introduced. The effectiveness of the proposed technique is validated through 10, 33, 34 and85-bus radial distribution systems.

Soil Erosion and Sediment Yield Reduction Analysis with Land Use Conversion from Illegal Agricultural Farming to Forest in Jawoon-ri, Kangwon using the SATEEC ArcView GIS System (SATEEC ArcView GIS 시스템을 이용한 홍천군 자운리 유역 무허가경작지의 산림 환원에 따른 토양유실 및 유사저감 분석)

  • Jang, Won-Seok;Park, Youn-Shik;Kim, Jong-Gun;Choi, Joong-Dae;Lim, Kyoung-Jae
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • /
    • pp.1300-1304
    • /
    • 2008
  • The fact that soil loss causing to increase muddy water and devastate an ecosystem has been appearing upon a hot social and environmental issues which should be solved. Soil losses are occurring in most agricultural areas with rainfall-induced runoff. It makes hydraulic structure unstable, causing environmental and economical problems because muddy water destroys ecosystem and causes intake water deterioration. One of three severe muddy water source areas in Soyanggang-dam watershed is Jawoon-ri region, located in Hongcheon county. In this area, many cash-crops are planted at illegally cultivated agricultural fields, which were virgin forest areas. The purpose of this study is to estimate soil loss with current land uses (including illegal cash-crop cultivation) and soil loss reduction with land use conversion from illegal cultivation back to forest. In this study, the Sediment Assessment Tool for Effective Erosion Control (SATEEC) ArcView GIS system was utilized to assess soil erosion. If the illegally cultivated agricultural areas are converted back to forest, it is expected to 17.42% reduction in soil loss. At the Jawoon-ri region, illegally cultivated agricultural areas located at over 30% and 15% slopes take 47.48 ha (30.83%) and 103.64 ha (67.29%) of illegally cultivated agricultural fields respectively. If all illegally cultivated agricultural fields are converted back to forest, it is expected that 17.41% of soil erosion and sediment reduction, 10.86% reduction with forest conversion from 30% sloping illegally agricultural fields, and 16.15% reduction with forest conversion from 15% sloping illegally agricultural fields. Therefore, illegally cultivated agricultural fields located at these sloping areas need to be first converted back to forest to maximize reductions in soil loss reduction and muddy water outflow from the Jawoon-ri regions.

  • PDF