• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.181-184
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• 2004

The objective of this experimental study is to grasp the effect of replacement level of high-quality recycled aggregate on the properties of high-performance concrete. The mixing types were divided into two series based on containing $0\%\;and\;15\%$ fly-ash. Replacement level of recycled aggregate ranged from $0\%\;to\;100\%$. Test results showed that the initial slump and the fluid velocity were independent on the replacement level of recycled aggregate, and the loss of compressive strength was almost $20\%$ with the recycled aggregate only.

• 대한산업공학회지
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• 제4권1호
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• pp.1-3
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• 1978

This paper presents a model for determining the optimal number of minimal repairs before replacement. The basic concept parallels the periodic replacement model with minimal repair at failure introduced by Barlow and Hunter, only difference being the replacement signalled by the number of previous minimal repairs performed on the unit. In the case of Weibull distribution, which is widely used as a general failure distribution, the optimal solution could be obtained numerically and seems more cost effective compared to the Barlow and Hunter's Policy II.

• 한국식품조리과학회지
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• 제13권3호
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• pp.299-303
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• 1997

The effects of partial replacement of flour with isolated soy protein (ISP) on sponge cake quality were investigated. The replacement did not cause any significant changes in physical characteristics of sponge cakes including specific gravity, specific volume and expansion ratio. As the level of ISP replacement increased, the sponge cakes were darker in color, harder, chewier and drier than control groups. The textural characteristics (hardness, cohesiveness, springiness, gumminess and chewiness) of the sponge cakes also increased as the level of flour replacement increased. Up to 15％ of the flour could be replaced by ISP without diminishing the sponge cake quality.

• Asian-Australasian Journal of Animal Sciences
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• 제25권8호
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• pp.1124-1131
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• 2012

Four Thai - rumen fistulated male swamp buffaloes (Bubalus bubalis), about four years old with $400{\pm}20kg$ liveweight, were randomly assigned according to a $4{\times}4$ Latin square design to receive dietary treatments. The treatments were: ground corn cob (GCC) replacement for cassava chip (CC) in concentrate at 0% (T1); GCC replacement at 33% (T2); GCC replacement at 67% (T3); and GCC replacement at 100% (T4), respectively. During the experiment, concentrate was offered at 0.5% BW while 5% urea-treated rice straw was given at ad libitum. The result revealed that there was no effect of GCC replacement on DMI among treatments. In addition, digestibilities of DM, OM and CP were not different while aNDF linearly increased with an increasing level of GCC replacement. However, GCC replacement did not affect rumen fermentation such as ruminal pH, $NH_3$-N and VFA concentration; except C3 proportion which was the highest at 33% replacement while the lowest was at 100% replacement. All replacements of GCC resulted in similar protozoal and bacterial populations and microbial protein synthesis (MPS). Purine derivatives (PD) concentration in urine and PD to creatinine (PDC) index were varied with time of urination and among treatments at 0 to 8 and 8 to 16 h post feeding and higher values were shown among the GCC replacement groups. However at 16 to 24 h-post feeding, it was untraceable. In addition, creatinine concentration was similar among all treatments at every sampling time. Based on the above results, GCC can be used as an energy source for swamp buffalo fed with rice straw. Spot sampling of urine can be used for purine derivatives determination.

• 지질공학
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• 제17권4호
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• pp.601-613
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• 2007

연약지반에 보강토옹벽을 시공 시 거동에 영향을 주는 인자로 기본적인 물성뿐만 아니라 보강토옹벽에 의한 하중증가와 압밀기간, 간극수압 등의 영향을 받는 것으로 보고되고 있다. 본 연구에서는 보강토옹벽과 연약지반의 거동해석에 지반해석 프로그램인 SAGE CRISP를 이용하여 수행하였다. 첫 번째로 보강토옹벽의 과도변위를 개선하기 위한 치환공법의 거동 개선 효과를 검토하였으며, 두 번째로 치환공법을 적용 후 보강토옹벽의 배면에 보강재 수직설치간격이 지반의 거동에 미치는 영향을 비교 분석하였다. 마지막으로 치환공법을 적용 시 적정 치환 폭과 깊이를 제안하고자 하였다. 치환공법이 보강토옹벽의 거동 개선에 상당한 효과가 있음을 알 수 있었으며, 보강재 수직설치간격은 옹벽상단의 수평변위 개선효과가 있는 것으로 나타났으나 하단의 수평변위와 옹벽배면의 수직변위 개선효과는 미소한 것으로 나타났다. 또한 치환폭의 증가에 따른 수평 수직변 개선효과는 크지 않은 것으로 나타나 치환폭의 증가는 불필요함을 알 수 있었으며, 적정 치환깊이는 연약층의 두께에 대한 옹벽높이의 비(H/T)에 따라 옹벽높이에 대한 치환깊이의 비(D/H)로 제안하였다.

• Journal of Chest Surgery
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• 제13권4호
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• pp.405-413
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• 1980

A total of 63 patients [42 males and 21 females] underwent multiple valve replacement with artificial valves between January 1975 and August 1980 at Seoul National University Hospital. There were 38 patients with aortic and mitral valve replacement, 22 with mitral and tricuspid, and 3 with aortic, mitral and tricuspid valve replacement. The valve lesions varied from trivial to severe and most aortic and mitral valves had mixed stenosis and insufficiency, while tricuspid valves had only insufficiency. The patients were severely symptomatic in majority of the cases, and belonged to the Classes III and IV [III:45, IV:16] of the NYHA functional criteria. Hemodynamic studies were performed on all the patients. The mean pulmonary wedge pressure was remarkably increased to 19.8 mmHg in aortic and mitral valve lesions and 18.0 mmHg in mitral and tricuspid valve lesions. The mean pulmonary arterial pressure was also increased, while the cardiac index was reduced. In 1977, the average perfusion time was 245.5 minutes for aortic and mitral valve replacement and 181.6 minutes for mitral and tricuspid valve replacement. It has progressively declined to 169.2 minutes for aortic and mitral valve replacement and 123 minutes for mitral and tricuspid valve replacement in 1980. The average period of aortic occlusion also declined after the use of cardioplegic solution. Twenty deaths occurred among the 63 patients operated upon, an overall mortality rate of 30.8%. The operative mortality has declined with successive year from a level of 66.7% before 1977 to 21.1% in 1980. Fourteen patients suffered from a list of postoperative complications, which eventually resolved with adequate treatment. All the survivors were enjoying the levels of daily life activities greater than those existing before the operation.

• Computers and Concrete
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• 제17권3호
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• pp.423-433
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• 2016

After the industrial of steelmaking by-products are processed properly, they can be used in civil engineering, not only as a substitute for natural resources and to reduce costs, but also to provide environmental protection. This study used different amounts (10%, 20%, 30%, 40%,and 50%) of desulphurization slag to replace natural fine aggregates in ready-mixed soil materials, and tested the physical and fresh properties (slump, slump flow, tube flow, initial setting time, and bleeding) and hardened properties (compressive strength, ball drop, ultrasonic pulse velocity) of the materials. The variations between the performances of the materials with different mix proportions were discussed. When desulphurization slag is used in RMSM, the workability can be enhanced obviously significantly. When the replacement of desulphurization slag is 50%, the slump flow is increased by 110mm compared with the control group, and the initial setting time increases as the replacement increases, because of bleeding. When the replacement is 10% and 20%, the compressive strength at various ages is higher than that of the control group. When the replacement is 10%, the compressive strength at 7 days is higher than that of the control group by 60%, and the ultrasonic pulse velocity is proportional to the compressive strength, which increases with age and decrease as the replacement increases. An appropriate replacement can effectively accelerate construction, and allow projects to be finished ahead of schedule; therefore, an appropriate replacement, is applicable for ready-mixed soil materials.

• 한국정보처리학회논문지
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• 제3권7호
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• pp.1669-1679
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• 1996

In this paper, we address the problem of how to replace huffers in multimedia database systems with time-varying skewed data access. The access pattern in the multimedia database system to support audio-on-demand and video-on-demand services is generally skewed with a few popular objects. In addition the access pattem of the skewed objects has a time-varying property. In such situations, our analysis indicates that conventional LRU(least Recently Used) and LFU(Least Frequently Used) schemes for buffer replacement algorithm(ABRN:Adaptive Buffer Replacement using Neural suited. We propose a new buffer replacement algorithm(ABRN:Adaptive Buffer Replacement using Neural Networks)using a neural network for multimedia database systems with time-varying skewed data access. The major role of our neural network classifies multimedia objects into two classes:a hot set frequently accessed with great popularity and a cold set randomly accessed with low populsrity. For the classification, the inter-arrival time values of sample objects are employed to train the neural network.Our algorithm partitions buffers into two regions to combine the best roperties of LRU and LFU.One region, which contains the 핫셋 objects, is managed by LFU replacement and the other region , which contains the cold set objects , is managed by LRUreplacement.We performed simulation experiments in an actual environment with time-varying skewed data accsee to compare our algorithm to LRU, LFU, and LRU-k which is a variation of LRU. Simulation resuults indicate that our proposed algorthm provides better performance as compared to the other algorithms. Good performance of the neural network-based replacement scheme means that this new approach can be also suited as an alternative to the existing page replacement and prefetching algorithms in virtual memory systems.

• Asian-Australasian Journal of Animal Sciences
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• 제15권1호
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• pp.45-54
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• 2002

Ninety lactating goats (Bachthao, Barbary, Beetal and Jamnapary breeds) were used in an experiment to investigate the replacement value of the tree fodders Flemingia (Flemingia macrophylla) and Jackfruit (Artocarpus heterophyllus). The foliages were used to replace the concentrate in diets based on chopped whole sugar cane (Sacharatum sp.), Para grass (Brachiaria mutica) and dried cassava root (Manihot esculanta). The concentrate was replaced by foliage of Jackfruit or Flemingia at 0%, 20%, 40%, 60% and 80% based on the crude protein (CP) content in the concentrate and foliages, respectively. Average milk yield was 1,617 g/day for goats fed Jackfruit compared to 1,532 g/day for those fed Flemingia. Increasing amounts of Flemingia foliage resulted in reduced dry matter intake and decreased milk yield but milk composition (CP, casein and fat content) was similar up to 60% replacement. Flemingia showed a poor potential as a supplement for lactating goats and replacement levels should not exceed 20% of the protein in the concentrate or 7.5% of the dry matter in the diet. With respect to the combination of milk production and net return over the control a CP replacement rate of 20% was the most promising. For Jackfruit there was similar feed intake and milk yield at a replacement level of 20% of CP in the concentrate (9.2% of DM intake) compared to the control diet. Milk yield at the level of 40% replacement (15% of the DM) in the diet was slightly reduced. Up to a level of CP replacement rate of 60% (21% DM in the diet) can be suggested for on-farm testing as a higher net return over the control was obtained on station.

• 한국건축시공학회지
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• 제2권4호
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• pp.169-176
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• 2002

To study of binder and fine aggregate a lot of replacement fly-ash concrete, initial characteristics, standard environment of curing temperature $20^{\circ}C$, hot-weather environment, cold weather environment of curing temperature $5^{\circ}C$. Flash concrete tested slump, air contest, setting and Hardening concrete valuated setting period of form, day of age 3, 7, 28 compression strength in sealing curing. Underwater curing specimen compression strength of age 3. 7, 28day used strength change accordingly fly-ash concrete curing temperature. Purpose of study is consultation materials in field that variety of fly-ash replacement concrete mix proportion comparison and valuation. (1) Setting test result, fly-ash ratio of replacement higher delay totting time. Same volume of fly-ash ratio of replacement is lower fly-ash ratio of replacement fine aggregate delay setting time. Setting test in curing temperature $35^{\circ}C$ over twice fast setting in curing temperature $20^{\circ}C$ and all specimen setting delay in curing temperature $5^{\circ}C$. F40 specimen end of setting about 30 time. (2) Experiment result age 28day compression strength more fisher plan concrete then standard environment in curing temperature $20^{\circ}C$, cold weather environment in curing temperature $5^{\circ}C$, most strength F43 is hot-weather environment in curing temperature $35^{\circ}C$ replacement binder 25%, fine aggregate 15%. (3) Hot-weather environment replacement a mount of fly-ash is a same of plan concrete setting period of form. Age 28day compression strength replacement a mount of fly-ash more hot-weather concrete then plan concrete.