• Title/Summary/Keyword: Progressive reduction

Search Result 153, Processing Time 0.025 seconds

Man-hour Reduction by Development of Library in a 3-D Design System for Plant Projects (플랜트 프로젝트용 3차원 디자인 시스템에서 라이브러리 개발을 통한 설계시간 감축)

  • Lee, Jung-Hyun;Moon, Seung-Jae;Yoo, Hoseon
    • Plant Journal
    • /
    • v.5 no.4
    • /
    • pp.68-72
    • /
    • 2009
  • This study discussed for library development of the 3 dimensional design system for the progressive developmental world wide plant industry. Its previous background had spatial limitation by utilizing 2 dimensional CAD. This work presented an effective mode for improving man-hour by applying with 3 dimensioal design system through theoretical definition, category, and means of basic man-hour. We researched an effective method for reducing man-hour through applied example on the actual project by comprehending affection of extra development for library on man-hour.

  • PDF

Multiattribute Decision Making with Ordinal Preferences on Attribute Weights

  • Ahn Byeong Seok
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 2004.10a
    • /
    • pp.143-146
    • /
    • 2004
  • In a situation that rank order information on attribute weights is captured, two solution approaches are presented. An exact solution approach via interaction with a decision-maker pursues progressive reduction of a set of non-dominated alternatives by narrowing down the feasible attribute weights set. In approximate solution approach, on the other hand, three categories of approximate methods such as surrogate weights method, the dominance value-based decision rules, and three classical decision rules are presented and their efficacies in terms of choice accuracy are evaluated via simulation analysis. The simulation results indicate that a method, which combines an exact solution approach through interactions with the decision-maker and the dominance value-based approach is recommendable in a case that a decision is not made at a single step under imprecisely assessed weights information.

  • PDF

Sound Radiation due to Tire Tread Vibration (타이어 트레드의 진동에 의한 음향방사)

  • Kim, Byoung-Sam;Hong, Dong-Pyo;Chung, Tae-Jin
    • The Journal of the Acoustical Society of Korea
    • /
    • v.13 no.2
    • /
    • pp.13-22
    • /
    • 1994
  • A theoretical model is studied to describe the sound radiation by the surface vibration of in-service tires. The tire is modeled as a circular ring model. The effects of normalized frequency and structrual loss factor are included. Through numerical integration of the sound pressure, the radiated sound power is calculated as a fuction of normalized frequency and structural loss factor. The basic sound radiation mechanism is shown to be the damped progressive wave field on the structure in the vicinity of the applied force. The results indicate that the potential sound reduction might be obtained if values of normalized frequency and structural loss factor are investigated.

  • PDF

Rebar corrosion effects on structural behavior of buildings

  • Yuksel, Isa
    • Structural Engineering and Mechanics
    • /
    • v.54 no.6
    • /
    • pp.1111-1133
    • /
    • 2015
  • Rebar corrosion in concrete is one of the main causes of reduction of service life of reinforced concrete buildings. This paper presents the influence of rebar corrosion on the structural behavior of reinforced concrete (RC) buildings subjected to strong earthquake ground motion. Different levels of rebar corrosion scenarios were applied on a typical four story RC frame. The deteriorated conditions as a result of these scenarios include loss in cross-sectional area and loss of mechanical properties of the reinforcement bars, loss in bond strength, and loss in concrete strength and its modulus of elasticity. Dynamic analyses of the frame with different corrosion scenarios are performed with selected strong earthquake ground motion records. The influences of degradation in both concrete and reinforcement on structural behavior are investigated by comparing the various parameters of the frame under different corrosion scenarios with respect to each other. The results show that the progressive deterioration of the frame due to rebar corrosion causes serious structural behavior changes such as change in failure mode. The intensity, propagation time, and extensity of rebar corrosion have very important effects on the level of degradation of steel and concrete, as well as on the earthquake behavior of the structure.

Reduction of CO2 Fertilization due to Progressive Nitrogen Limitation - Physiological Changes of Four Native Tree Species Growing under Elevated CO2 for 8 years using Open-Top Chamber (점진적 질소 제한으로 인한 이산화탄소 시비효과 감소 - 상부개방형 온실을 이용한 고농도의 이산화탄소 하에서의 우리나라 대표 수종들의 생리적 변화)

  • Song, Wookyung;Byeon, Siyeon;Lee, HoonTaek;Lee, Minsu;Lim, Hyemin;Kim, Hyun Seok
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
    • /
    • 2018.06a
    • /
    • pp.77-78
    • /
    • 2018
  • PDF

Innovative Therapeutic Approaches for Mucopolysaccharidosis III

  • Sohn, Young Bae
    • Journal of mucopolysaccharidosis and rare diseases
    • /
    • v.4 no.2
    • /
    • pp.37-41
    • /
    • 2018
  • Mucopolysaccharidosis III (MPS III, Sanfilippo syndrome) is a rare autosomal recessive disease caused by a deficiency of one of four enzymes involved in the degradation of glycosaminoglycan (GAG). The resultant cellular accumulation of GAG causes various clinical manifestations. MPS III is divided into four subtypes depending on the deficient enzyme. All the subtypes show similar clinical features and are characterized by progressive degeneration of the central nervous system. A number of genetic and biochemical diagnostic methods have been developed. However, there is no effective therapy available for any form of MPS III, with treatment currently limited to clinical management of neurological symptoms. Main purpose of the treatment for MPS III is to prevent neurologic deterioration. Because conventional intravenous enzyme replacement therapy (ERT) has a limitation due to inability to cross the blood-brain barrier, several innovative therapeutic approaches for MPS III are being developed. This review covers the currently developing new therapeutic options for MPS III including high dose ERT, substrate reduction therapy, intrathecal or intraventricular ERT, fusion protein delivery using bioengineering technology, and gene therapy.

Integral Method of Stability Analysis and Maintenance of Slope (비탈면 안정해석과 유지관리의 통합해석기법)

  • Park, Mincheol;Yoo, Byeongok;Baek, Yong;Hwang, Youngcheol
    • Journal of the Korean GEO-environmental Society
    • /
    • v.17 no.3
    • /
    • pp.27-35
    • /
    • 2016
  • Even if the various data analyzing methods were suggested to examine the measured slope behaviors, it is difficult to find methods or procedures for connecting the analyzed results of slope stability and measured slope data. This research suggests the analyzing methods combing the stability analysis and measured data based on progressive failure of slope. Slope failure analysis by time degradation were calculated by strength parameters composed of strength reduction coefficients, also which were compared to the measured data according to the variations of safety factor and displacement of slopes. The accumulated displacement curve were shown as 3rd degree polynomials by suggested procedures, which was the same as before researches. The reverse displacement velocity curves were shown as linear function for prediction of brittle slope failures, also they were shown as 3rd degree polynomials for ductile slope failures, which were the same as the suggested equation by Fukuzono (1985) and they were very similar behaviors to the in-situ failure cases.

Analysis for the Economic efficiency of District Heating and Gas Engine Co-generation System comparing with Central Heating System (중앙난방방식을 지역난방.소형열병합난방방식으로 전환시의 경제성 비교 분석)

  • Kim, Kyu-Saeng;Lee, Sang-Hyeok;Hong, Kyung-Pyo;Won, Young-Jae
    • Proceedings of the SAREK Conference
    • /
    • 2007.11a
    • /
    • pp.459-465
    • /
    • 2007
  • This study was conducted to calculate the LCC of a apartment complex with a type of heating system, district heating and cogeneration system. For the purpose of analyzing LCC according to size of apartment complex, 500, 1,500 and 4,000 houses of model apartment selected. This research performs design of heating system and the life cycle cost analysis including an initial cost, energy cost, maintenance and operation cost, replacement cost and renovation cost during the project period(15years). According to the calculated results, 1) Initial cost of cogeneration system with 500, 1500 and 4000 houses is higher than district heating system each of 20%, 13%, 12%. 2) In case of cogeneration system, the payback period by electric generation is 5.21, 4.92 and 4.47 years and saving cost was calculated 29 billion won, 94 billion won and 262 billion won after payback period. 3) Cogeneration system LCC was 1.12, 1.07 and 1.06 times larger than district system with the size of apartment complex. According to the case of this study district heating system is more efficient than cogeneration system in terms of the reduction of LCC. 4) Gas Engine Co-generation System is more efficient than other systems because it can collect progressive part from electric charge progressive stage system. However, the efficiency is decreasing because of raising of fuel bills(LNG) and lowering of power rate for house use. Especially the engine is foreign-made so the cost of maintenance and repair is high and the technical expert is short. 5) District heating is also affected by fuel bills so we should improve energy efficiency through recovering of waste heat(incineration heat, etc.). Also, we should supply district cooling on the pattern of heat using of let the temperature high in winter and low in summer.

  • PDF

Numerical Investigation of the Progressive Failure Behavior of the Composite Dovetail Specimens under a Tensile Load (인장하중을 받는 복합재료 도브테일 요소의 점진적인 파손해석)

  • Park, Shin-Mu;Noh, Hong-Kyun;Lim, Jae Hyuk;Choi, Yun-Hyuk
    • Composites Research
    • /
    • v.34 no.6
    • /
    • pp.337-344
    • /
    • 2021
  • In this study, the progressive failure behavior of the composite fan blade dovetail element under tensile loading is numerically investigated through finite element(FE) simulation. The accuracy of prediction by FE simulation is verified through tensile testing. The dovetail element is one of the joints for coupling the fan blade with the disk in a turbofan engine. The dovetail element is usually made of a metal material such as titanium, but the application of composite material is being studied for weight reduction reasons. However, manufacturing defects such as drop-off ply and resin pocket inevitably occur in realizing complex shapes of the fan blade made by composite materials. To investigate the effect of these manufacturing defects on the composite fan blade dovetail element, we performed numerical simulation with FE model to compare the prediction of the FE model and the tensile test results. At this time, the cohesive zone model is used to simulate the delamination behavior. Finally, we found that FE simulation results agree with test results when considering thermal residual stress and through-thickness compression enhancement effect.

The Effect of Korean version of Mindfulness-Based Stress Reduction Program on Chronic Pain of Workers. (한국형 마음 챙김 명상에 기반한 스트레스 감소 프로그램이 만성통증에 미치는 효과)

  • Susie Kim ;Sang-sub Ahn
    • Korean Journal of Culture and Social Issue
    • /
    • v.15 no.3
    • /
    • pp.359-375
    • /
    • 2009
  • This study developed a program that integrated MBSR-K and progressive muscular relaxation for the health and well-being of patients with chronic pain, and proved its effectiveness by studying 40 chronic pain patients. This program used nature of mind, body scanning meditation, breath meditation, mindfulness meditation, Hatha yoga and progressive muscular relaxation to ease chronic pain. Whenever negative feelings and emotions such as fear, anxiety, and pain occurred, the program focused on those emotions and observed the outcome. This program, which was based on the results of the preceding studies, was composed of eight courses. Major findings of the study are as follows: First, the meditation group that was composed of patients with chronic pain had significant decrease of physical symptoms compared to the control group. Second, to confirm the outstanding features of the participating patients with chronic pain that brought change in the effect of the program, characteristics of clients were analysed. Third, the program factor that influenced the effectiveness of the treatment process was evident when the training was performed twice a week rather than having once a week of training and second week for homework.

  • PDF