• 한국지진공학회논문집
• /
• 제17권3호
• /
• pp.107-115
• /
• 2013

The purpose of this study was to investigate the performance of hollow reinforced concrete bridge column sections with reinforcement details for material quantity reduction. The proposed reinforcement details has have economic feasibility and rationality and makes construction periods shorter. A model of column sections with reinforcement details for material quantity reduction was tested under quasistatic monotonic loading. As a result, the proposed reinforcement details for material quantity reduction was were equal to existing reinforcement details in terms of the required performance. In the a subsequent paper, the an experimental and analytical study will be performed for the performance assessment of hollow reinforced concrete bridge column sections with reinforcement details for material quantity reduction will be performed.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2007년도 춘계학술대회 논문집
• /
• pp.798-803
• /
• 2007

The brake system of railway plays an important role to enhance the speed of train, and the brake disc is one of major components relating to frictional braking. The performance enhancement of brake disc directly affects the braking performance of train. It is required to understand and investigate the factors need to be considered for the development of new brake disc with improved materials and performance. In this study, through the literature reviews of previous study, several factors including thermal crack phenomena, friction coefficient, materials and durability of disc, temperature characteristics, etc., were introduced for the design of improved brake disc. Moreover, based on the review results, the design direction of new brake disc was suggested. Eventually, a new brake disc with improved performance would be developed based on this investigation.

• 전기학회논문지
• /
• 제59권10호
• /
• pp.1727-1732
• /
• 2010

The Current transformer is classified measuring CT and protective CT for their purpose. The measuring CT is required to retain a specified accuracy over the normal range of load currents, but the protective CT must be capable of providing an adequate output over wide range of fault condition. Therefore, the protective CT must determine the transient performance during fault condition. This paper measured peak instantaneous error of the TPY class CT to determine the transient performance directly and indirectly and studied the test results.

• 한국안전학회지
• /
• 제32권5호
• /
• pp.54-61
• /
• 2017

The purpose of this study is to develop standard reference materials for safety control of construction materials considering the required performance of standard materials including flow performance incorporating particles. The flow characteristics of concrete are very complicated depending on mixing proportions of constituent materials, admixtures, amount of mixing, type of mixer, time of mixing, temperature and so forth. Uncertainties and multidimensional properties of concrete have been evaluated through various studies but there are few researches for the development of standard reference material. In this study, based on the rheological concept, the flow performance of construction materials was evaluated to understand the properties of standard reference materials and was finally obtained representing materials which simulate the standard reference materials.

• Architectural research
• /
• 제17권2호
• /
• pp.75-81
• /
• 2015

Insulation and condensation performance evaluation (I&CPE) is an important energy analysis. While considerable amount of data are already represented in a Building Information Model (BIM), the lack of interoperability between BIM modeling and I&CPE programs prevents the simulation process from being efficient and accurate. This study proposes a prototype of a BIM-based I&CPE simulation program, in order to enhance the interoperability between BIM modeling and I&CPE programs. This study discusses the information flow process, defines the required information and its level of detail, develops standardized libraries, and finally proposes a prototype that consists of a data extraction module, conversion module, and performance module. The assurance of interoperability between systems might greatly benefit architects and energy professionals.

• Asian-Australasian Journal of Animal Sciences
• /
• 제12권6호
• /
• pp.956-965
• /
• 1999

Genetic selection and sophisticated management technology have produced modern sows which excel in litter size and milk production. Recent research has identified nutritional innovations which may enhance productivity of the high producing sow. Selected research in three areas which have the potential to enhance reproductive performance are summarized in this report. First, preliminary evidence indicates that organic chromium may enhance litter size and conception rate. Secondly, high producing sows, particularly primiparous sows, required higher protein/lysine in late gestation and or lactation to optimize weaning weight and subsequent litter size. Valine and isoleucine, but not leucine, have been shown to enhance milk production. Phased feeding programs with diet cost partitioned toward gilts and away form parity 3 to 8 sows have been suggested as a means of improving reproductive performance in young sows. Lastly, recent research with sufficient sow numbers to document the effect of dietary fiber on reproductive performance has shown that sows fed fiber farrowed and weaned more pigs.

• Asian-Australasian Journal of Animal Sciences
• /
• 제6권1호
• /
• pp.61-66
• /
• 1993

Sixteen Korean native bulls weighing about 211 kg were randomly allotted to investigate the effect of different dietary calcium levels on performance. Feeding period was divided into growing period and fattening period for 180 days. Four calcium levels (0.44, 0.58, 0.72 and 0.86%) were used to each period. Bulls fed the diet containing 0.72% calcium had greater body weight gain and consumed more feed than bulls fed diets containing 0.44, 0.58 and 0.86% calcium and improved in feed efficiency. Bulls fed the diet containing 0.44% calcium were worst in performance. It can be concluded that Korean native bulls in growing and fattening period required no more than 0.72% calcium in diet that contained 0.55% phosphorus, and appeared that when ratio of calcium to phosphorus intake was 1.45, performance of Korean native bulls was most beneficial.

• 경영과학
• /
• 제34권2호
• /
• pp.35-56
• /
• 2017

Technology innovations have been accelerating changes across industries and intensifying competition. Enterprises are therefore required to continuously secure their internal and external competitiveness. Based on the principle that core competencies of a firm are essential to its competitiveness, many research studies have been conducted to figure out the effect of core competencies to business performance. However, individual research works considered a part of core competencies or limited to a specific industry, which means that their findings may differ when additional core competencies are included in their analysis. After re-establishing the definition of each core competency from literature review, this study comprehensively investigated the effect relationship among core competencies and business performance. Structural equation modeling and multiple regression analysis with 421 survey respondents from various industries were conducted for our empirical study.

• Asian-Australasian Journal of Animal Sciences
• /
• 제5권1호
• /
• pp.91-95
• /
• 1992

Two experiments were conducted to evaluate the performance of broilers and layers fed locally produced fish waste meal (LFWM) in Western Samoa. LFWM, which was produced by mincing and oven drying of rejects from filleted fish, was included in both broiler and layer diets at the complete expense of imported meat and bone meal (MBM). The experiments were of a completely randomised design. In experiment 1, 120 day-old Strabro broiler chicks were raised to 49 days of ages. In experiment 2, 80 Shaver 288 pullets, 20 weeks of age, were housed in pairs in cages and raised up to 72 weeks of age. There were no differences (p > 0.05) in performance of broilers as measured in terms of final bodyweights, feed intake, feed efficiency and carcass yield between the two diets. Similarly, no differences (p > 0.05) existed in egg production, egg weight and feed required per kilogramme of eggs. It is concluded that LFWM is nutritionally as good as imported MBM and could be used to completely replace MBM in broiler and layer diets.

• 유체기계공업학회:학술대회논문집
• /
• 유체기계공업학회 2005년도 연구개발 발표회 논문집
• /
• pp.497-502
• /
• 2005

In this study. the effect of volute area distribution on the performance of a centrifugal pump were numerically studied using a commercial CFD code. To reduce the shutoff head, maintaining head and efficiency at a design flow rate. the flat head-capacity characteristic curves in which the head varies only slightly with capacity from shutoff to design capacity are frequently required. In order to control the shutoff head of a pump, several volute cross-sectional area distributions were proposed as a main parameter with the same impeller geometry. The calculation results show that the slope of the performance characteristic curve of the centrifugal pump can be controlled by modifying the area distribution from volute tongue to volute outlet with fixed volute outlet area and also varied volute outlet area.