• Title/Summary/Keyword: reduction

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Development of Estimation Technique for Rice Yield Reduction by Inundation Damage (침수피해에 의한 벼 감수량 추정기법 개발)

  • Park , Jong-Min;Kim , Sang-Min;Seong, Chung-Hyun;Park, Seung-Woo
    • Journal of The Korean Society of Agricultural Engineers
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    • v.46 no.5
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    • pp.89-98
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    • 2004
  • The amount of rice yield reduction due to inundation should be estimated to analyse economic efficiency of the farmland drainage improvement projects because those projects are generally promoted to mitigate flood inundation damage to rice in Korea. Estimation of rice yield reduction will also provide information on the flood risk performance to farmers. This study presented the relationships between inundated durations and rice yield reduction rates for different rice growth stages from the observed data collected from 1966 to 2000 in Korea, and developed the rice yield reduction estimation model (RYREM). RYREM was applied to the test watershed for estimating the rice yield reduction rates and the amount of expected average annual rice yield reduction by the rainfalls with 48 hours duration, 10, 20, 50, 100, 200 years return periods.

An Experimental Study on the Properties Analysis of Concrete Using Bleeding Reduction Agent (블리딩 저감제를 사용한 콘크리트의 성능분석에 관한 실험적 연구)

  • 전충근;김경민;황인성;신병철;한천구
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.669-674
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    • 2002
  • This paper describes the properties analysis of concrete using bleeding reduction agent. According to the results, the fluidity and the air content of fresh concrete with increase of bleeding reduction agent show little difference in compare with plain concrete which does not use bleeding reduction agent. The efficiency of bleeding reduction agent is confirmed because in variation of W/C and slump, the increase of bleeding reduction agent dosage reduces bleeding remarkably. And the compressive strength of hardened concrete does not show any differences with increase the dosage of bleeding reduction agent. Bleeding reduction agent does not have bad effect on the quality of concrete such as fluidity, air content and the strength of hardened concrete and so on, the dosage of it can reduce bleeding effectively.

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A Study on Price Reduction under CISG and Issues

  • HAN, Ki-Moon
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.69
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    • pp.45-62
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    • 2016
  • Price reduction under CISG Art. 50 is advantageous to a buyer because it is a self-help remedy to the buyer. It is the buyer that has the option and the power to reduce the price paid or to be paid to the seller. Price reduction is indispensable in such cases where the seller is relieved of liability. In such cases the remedy of price reduction is the only one giving the buyer monetary relief. Another special role of price reduction is to determine how much the buyer owes the seller for non-conforming goods when special circumstances relieve the seller of liability for damages. In any event, price reduction has been designed both as an alternative to damages and for cases where the non-performing party is excused from liability for damages. The price reduction remedy however leaves several issues for clarification and application in several respects.

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Evaluation of the Established Reduction Scheme in Implementation Plan of Total Maximum Daily Loads (수질오염총량관리 시행계획에서 수립된 삭감계획의 평가)

  • Park, Jae Hong
    • Journal of Korean Society on Water Environment
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    • v.24 no.3
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    • pp.297-305
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    • 2008
  • It is necessary to select proper reduction methods and to calculate reasonably reduction amount for making good practice of the reduction scheme. Moreover, it is suggested that the reduction amount have to be distributed properly during the planning period. In other words, it has not to be concentrated on the specific year (especially final year of the planning period). The reason why, if the reduction amount concentrate on the final year of the planning period, allotment loading amount could not be achieved in some cases (e.g., insufficiency of budget, extension of construction duration). Even though much of the budget have been supported from national treasury (about 50%), it is thought the role of the local government must be strengthened gradually.

Laparoscopic Surgery for Intussusception in Children (소아 장중첩증에 대한 복강경 수술의 경험)

  • Yoon, Doo Hwan;Nam, So-Hyun
    • Advances in pediatric surgery
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    • v.19 no.2
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    • pp.66-72
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    • 2013
  • Intussusception is common cause of intestinal obstruction in children. Most of intussusceptions can be treated with non-operative reduction using air or barium. However, about 10% patients need operative treatment due to failure of reduction, peritonitis, and recurrence after reduction. We introduce our experience of laparoscopic surgery for intussusception. From April 2010 to March 2013, we reviewed 57 children who diagnosed intussusception. Twelve patients underwent an operation. The cause of operation was 7 of failure of air reduction and 5 of recurrence after air reduction. Median age was 21.5 months (range: 5.0~57.7 months) and 11 children (91.7%) underwent successful laparoscopic reduction. Median operating time was 50 minutes (range: 30~20 minutes) and median hospital days was 4.5 days (range: 3~8 days). One patient had a leading point as a heterotopic pancreas and underwent bowel resection through conversion. There was neither intra-operative nor postoperative complication. Laparoscopic reduction for intussusception can bring an excellent cosmetic effect with high success rate.

A Study on the Drag Reduction of Shear Thinning Fluid with Vertical upward Turbulent Flow (전단박화유체의 수직상향 난류유동시 저항감소에 관한 연구)

  • Cha, Kyong-Ok;Kim, Bong-gag;Kim, Jea-Geun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.12
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    • pp.1647-1656
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    • 1998
  • The drag reduction is the phenomenon that occurs only when the shear stress from the wall of pipe is beyond the critical point. The drag reduction increase as the molecular weight, concentration of the polymer and Reynolds number increase, but it is limited by Virk's maximum drag reduction asymptote. Because of the strong shear force for the polymer on the turbulent flow, the molecular weight and the drag reduction do not decrease. Such mechanical degradation of the polymer occurs in all polymer solvent systems. This paper is to identify and develop high performance polymer additives for fluid transportations with the benefits of turbulent drag reduction. In addition, drag reduction in vertical flow by measuring the pressure drop and local void fraction on vertical-up flow of close system is evaluated.

A BIJECTIVE PROOF OF THE SECOND REDUCTION FORMULA FOR LITTLEWOOD-RICHARDSON COEFFICIENTS

  • Cho, Soo-Jin;Jung, Eun-Kyoung;Moon, Dong-Ho
    • Bulletin of the Korean Mathematical Society
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    • v.45 no.3
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    • pp.485-494
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    • 2008
  • There are two well known reduction formulae for structural constants of the cohomology ring of Grassmannians, i.e., Littlewood-Richardson coefficients. Two reduction formulae are a conjugate pair in the sense that indexing partitions of one formula are conjugate to those of the other formula. A nice bijective proof of the first reduction formula is given in the authors' previous paper while a (combinatorial) proof for the second reduction formula in the paper depends on the identity between Littlewood-Richardson coefficients of conjugate shape. In this article, a direct bijective proof for the second reduction formula for Littlewood-Richardson coefficients is given. Our proof is independent of any previously known results (or bijections) on tableaux theory and supplements the arguments on bijective proofs of reduction formulae in the authors' previous paper.

Theoretical Considerations on an Electrolytic Reduction Process for Reducing Spent Oxide Fuel

  • Park B. H.;Seo C. S.;Jung K.-J.;Park S. W.
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.11b
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    • pp.86-91
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    • 2005
  • A metal product obtained from an electrolytic reduction process, possesses less volume and radioactivity than those of the unprocessed spent oxide fuels. The chemical composition of the metal product varies according to the process condition. In this work, a basic study was performed to evaluate the chemical forms of the spent oxide fuel components in an electrolytic reduction process with the operation conditions. One of the most important operation conditions is the cell potential applied for the reduction cell. It is expected that $PU_{2}O_3$ is difficult to reduce even though the cell potential is negative enough to reduce the lithium oxide when the activity of $Li_{2}O$ exceeds 0.003. The reduction of actinide oxides via the reduction of $Li_{2}O$ is assumed to have a greater reduction yield than a direct reduction of the actinide oxides.

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Study on the Reactivity of Sodium Phosphate Ammonium Chloride pH Reduction Agents (인산나트륨계 염화암모늄 pH저감제의 반응성 검토)

  • Shin, Ki-Don;Gao, San;Lee, Gun-Cheol
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.11a
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    • pp.105-106
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    • 2017
  • Previous studies have confirmed the performance of pH reduction agents using liquid sodium phosphate based ammonium chloride as a pH reduction agent. In this study, the pH reduction performance considering economical and applicability as a practical stage and the property change analysis for the identification of the reaction mechanism of the pH reduction agent were carried out. As a result, the pH reduction performance at a low rate of the pH reducing agent was confirmed. The specific gravity of CaO decreased significantly after XRF analysis. It is also believed that this reduces the amount of Ca(OH)2 produced and contributes to pH reduction.

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Washing Fastness of Polyester Artificial Suede Fabric According to Reduction Clearing Method (환원세정방법에 따른 스웨드 직물의 세탁견뢰도)

  • 강연희;백진주;서말용;김삼수;허만우;이난형
    • Textile Coloration and Finishing
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    • v.13 no.4
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    • pp.234-240
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    • 2001
  • In order to improve the washing fastness of dyed polyester artificial suede fabric, it was dyed by using auto and anthraguinone type disperse dyes and treated with 3 different reduction clearing methods. The reduction clearing methods used in this study were normal alkaline reduction clearing, $N_2$ gas replacement method, and ultrasonic treatment during normal reduction clearing. The results were as followings ; The washing fastness property of dyed polyester artificial suede fabric was slightly improved by reduction clearing with $N_2$ gas replacement or with ultrasonic treatment comparing with normal alkaline reduction clearing. It was found that the use of $N_2$ gas replacement or ultrasonic treatment during reduction clearing eave effective removal of unfixed dyes on the fiber surface. We also obtained that the azo type disperse dye on polyester artificial fabric suede fabric showed higher wash fastness than anthraquinone type disperse dye.

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