• Advances in concrete construction
• /
• 제6권2호
• /
• pp.103-121
• /
• 2018

This paper reports the effects of coarse and fine recycled concrete aggregates (RCA) on fresh and hardened properties of self-compacting concrete (SCC) containing ground granulated blast-furnace slag (GGBFS) as cement replacement. For this purpose, three SCC mixes groups, were produced at a constant water to binder ratio of 0.38. Both fine and coarse recycled aggregates were used as natural aggregates (NA) replacement at different substitution levels of 0%, 25%, 50%, 75% and 100% by volume for each mix group. Each group, included 0, 15% or 30% GGBFS as Portland cement replacement by weight. The SCC properties investigated were self-compactability parameters (i.e., slump flow, T500 time, V-funnel flow time, L-box passing ability and sieve stability), compressive strength, capillary water absorption and water penetration depth. The results show that the combined use of RCA with GGBFS had a significant effect on fresh and hardened SCC mixes. The addition of both fine and coarse recycled aggregates as a substitution up to 50% of natural aggregates enhance the workability of SCC mixes, whereas the addition from 50 to 100% decreases the workability, whatever the slag content used as cement replacement. An enhancement of workability of SCC mixes with recycled aggregates was noticed as increasing GGBFS from 0 to 30%. RCA content of 25% to 50% as NA replacement and cement replacement of 15% GGBFS seems to be the optimum level to produce satisfactory SCC without any bleeding or segregation. Furthermore, the addition of slag to recycled concrete aggregates of SCC mixes reduces strength losses at the long term (56 and 90 days). However, a decrease in the capillary water absorption and water permeability depth was noticed, when using RCA mixes with slag.

• 한국농촌건축학회논문집
• /
• 제19권2호
• /
• pp.9-16
• /
• 2017

The study analyzed the heat losses and the building energy efficiency grade by the energy simulation using the ENERGY# and ECO2 programs for the three types of Standard design of rural houses. It was calculated the energy efficiency rating by the ECO2 program for the rural housing standard design, and the energy demand and the energy consumption by each factor were compared and analyzed. And it analyzed energy consumption by element of each house by ENERGY # program. As a result, first in the evaluation of the energy efficiency grade of buildings by the ECO2 program, the rating for primary energy requirement for the housing newly built by the standard design of rural house is expected to range from 2 to 4 with 189.3 to $238.7kWh/m^2.a$. Second, the energy loss of each part of standard design of rural housing occurs in the order of ventilation 39%, window 33%, outer wall 14%, roof 9%, bottom 5%, and energy loss through ventilation and window occurs more than 70%. Third, the most beneficial effects on the energy efficiency grade is obtained the lowest grade of all three types by 2 when the lowering of the window and door heat transmission rate and the lowering of the light density, and the heat exchange ventilation device is not installed. Fourth, in the standard design of rural housing, the energy demand is occupied by heating > hot water > lighting order, and the order of the weight is changed in order of heating > lighting > ventilation > hot water. Fifth, building energy efficiency assessment system needs to establish policy for fixing rural housing energy as a practical device to ensure energy performance and quality.

• Journal of Animal Science and Technology
• /
• 제59권3호
• /
• pp.5.1-5.10
• /
• 2017

Background: Bovine respiratory disease (BRD) is one of the leading causes of economic losses in the beef and dairy industry. Reliable antemortem tools for diagnosing BRD would improve the efficacy of treatment and reduce costs. Here we examined whether the relatively simple technique of thoracoscopy can support BRD diagnosis under field conditions. We also compared various equipment set-ups in order to optimize the safety and efficacy of the procedure. A total of 24 thoracoscopic procedures were performed in 17 calves diagnosed with BRD and in 2 healthy control calves. Rigid and flexible endoscopes and industrial videoscopes were tested using various insertion approaches. The suitability of the technique was assessed in terms of duration, volume of air extracted, visualization score, and image quality. Safety was assessed in terms of rectal temperature, body weight, breaths/min, presence of fibrinogen, pain score, recovery time, intraoperative complications and risk of laceration or threatening collapse. Results: Insertion of a flexible endoscope via a right, dorso-caudal approach at the $5^{th}$ intercostal space allowed complete examination of the right lung in 15 min, as well as identification of main lung lesions and adherences in calves with BRD, without compromising calf welfare. While the dorso-caudal approach was optimal, it was associated with substantial discomfort when rigid endoscopes were used, minimal complications or mortality due to thoracoscopy were observed up to 28 days after the procedure. Videoscopes were as safe and easy to use as endoscopes, but endoscopes provided better image quality. Conclusion: This study provides the first field evidence that thoracoscopy can be safe to explore BRD-diseased calves. These results justify a larger study to rigorously assess the diagnostic performance of the technique.

• 식물병연구
• /
• 제16권3호
• /
• pp.285-289
• /
• 2010

호박 흰가루병의 수량감수 모델, 요방제 수준 및 경제적 방제수준을 산출하기 위하여 2008년부터 2년간 포장에서 시험하였다. 호박 흰가루병은 정식 후 50일경인 6월 하순에 발생하기 시작하여 7월 하순~8월 상순에 가장 심하였고, 그 이후 감소하는 경향을 보였다. 흰가루병의 발병정도와 수확 과실수, 과실의 생체중, 수량(생체중$\times$수확 과실수)간에는 고도의 부의 상관이 있었고 생체중과 상품과율은 정의 상관을 보였다. 흰가루병의 발병수준(X)에 따른 호박의 수량(Y) 추정 단순직선회귀식은 Y = -10.399X + 6607.5였고 결정계수($R^2$)는 0.9700으로 모델의 적합도가 매우 높았다. 방제비용을 고려하지 않은 흰 가루병의 요방제 수준은 병반면적율 6.5%였으며, 방제비용을 정당화 시킬 수 있는 경제적 피해수준은 병반면적율 21.6%였고, 농가에서 실제로 적용 가능한 경제적 방제수준은 병반면적율 17.3%로 산출되었다.

• 폴리머
• /
• 제30권4호
• /
• pp.357-361
• /
• 2006

생체 내에서 생성되는 알파 리포산은 산화방지, 혈당량 조절뿐만 아니라 식욕 억제, 비만 억제 효과 등을 가지고 있다. 약물로도 이용되고 있는 이 물질은 두 개의 황을 함유하고 있는 오각형 고리구조를 가지고 있어, 열과 자외선에 의해서 쉽게 개환되고 나아가 고분자로 중합될 수 있어서 약물로서 투여했을 경우 생체 이용률이 낮아지는 문제가 보고되어 있다. 본 연구는 개환에 따른 고분자화를 위한 다양한 조건을 조사하였다. 리포산은 녹는점이 지나야만 개환이 발생하였지만 그 이상의 온도에서는 온도의존성이 없었다. $70^{\circ}C$에서 개환율은 시간에 비례하였고 농도에 반비례하였다. 1시간 동안, $70^{\circ}C$ 아세트산에서 자외선과 함께 개환된 경우 개환율은 가장 높은 70% 였다. 이렇게 개환된 알파 리포산들은 대부분이 이황 고분자로 변했고, 개환율이 커질수록 고분자의 분자량 도 증가하였다.

• 한국근적외분광분석학회:학술대회논문집
• /
• 한국근적외분광분석학회 2001년도 NIR-2001
• /
• pp.1255-1255
• /
• 2001

The study used 356 veal calf meat samples received from Finland (n=16), France (n=109), Italy (n=81) and The Netherlands (n=150). Calves were raised under experimental protocols that compared feeding and housing practices normally used in each county to treatments aiming at improving animal welfare. Samples were taken at the $8^{th}$ rib of Longissimus thoracis muscle 24h after slaughter, They were kept refrigerated ( $2-4^{\circ}C$) under vacuum package for 6d and then frozen ($-20^{\circ}C$) until meat quality evaluation. Measurements included pH, color (Hunter Lab system), shear force, chemical composition (DM, Ash, Ether Extract, collagen and haematin content), weight and area cooking losses and a sensory evaluation by a group of panelists. A sample of meat was ground with a blade mill and scanned in duplicate between 1100 and 1498 nm (FOSS NIR Systems 5000). WinISI software was used to develop a discriminating equation using NIR spectra (SNV-detrend, derivative=1, gap=4nm, smooth=4nm). The Proc ANOVA and DISCRIM of SAS were used for all the laboratory determinations. County of production had a significant (P<0.01) effect on all the parameters. However, discriminant analysis using any or few laboratory parameters resulted in great errors of county classification. A more accurate (98.8%) classification was obtained only when using all the laboratory parameters. NIRS classified correctly 354 of the 356 samples (99.4%). Provided with a larger data set, NIRS could be used to identify country of production of veal meat.

• Journal of the Korean Wood Science and Technology
• /
• 제38권2호
• /
• pp.124-134
• /
• 2010

This study was performed to evaluate the efficiency of using softwood as the sawdust medium for Lentinula edodes cultivation, effect of nutrient on the mycelial growth, spawning, the mushroom yield, and quality. The nitrogen nutrition significantly enhanced the mycelial growth of L. edodes. The glutamic acid in the L. leptolepis and P. koraiensis, and asparagine in the P. densiflora were appeared to slight increase in the mycelial growth. The vegetable oil showed very effective on the mycelial growth in the P. koraiensis sawdust medium. Carbon/nitrogen ratio of all the test was reduced after mycelial growth. The mycelial growth was exclusively dependent on reduction of carbon. The mushroom yield (32.7%) of the P. densiflora sawdust medium (carbon source: 3% active carbon, nitrogen source: 0.4% asparagines) was the best in mushroom production of L. edodes, followed by the Q. variabilis sawdust (35.4%) of the control medium. The diameter of mushroom cap was obtained from the P. densiflora sawdust (carbon source: 3% sucrose, nitrogen source: 0.4% potassium nitrate) and P. koraiensis sawdust (carbon source: 3% sucrose, nitrogen source: 0.4% potassium nitrate), and the P. koraiensis sawdust (carbon source: 3% xylose, nitrogen source: 0.4% glutamic acid, supplement: 0.05% amino acid), with values 71.5 mm, 71.5 mm and 72.1 mm, respectively. In the polypropylene bag cultivation, the weight losses of the block medium gradually increased for 80 days in the dark (13.8~16.8%) and then became stable in the range of 20.7~25.8%.

• Journal of Power Electronics
• /
• 제18권5호
• /
• pp.1595-1607
• /
• 2018

In this paper, a hierarchical control strategy is introduced to control a new three-port multidirectional DC-DC converter for integrating an energy storage system (ESS) to a bipolar DC microgrid (BPDCMG). The proposed converter provides a voltage-balancing function for the BPDCMG and adjusts the states of charge (SoC) of the ESS. Previous studies tend to balance the voltage of the BPDCMG buses with active sources or by transferring power from one bus to another. Furthermore, the batteries available in BPDCMGs were charged equally by both buses. However, this power sharing method does not guarantee efficient operation of the whole system. In order to achieve a higher efficiency and lower energy losses, a triple-layer hierarchical control strategy, including a primary droop controller, a secondary voltage restoration controller and a tertiary optimization controller are proposed. Thanks to the multi-functional operation of the proposed converter, its conversion stages are reduced. Furthermore, the efficiency and weight of the system are both improved. Therefore, this converter has a significant capability to be used in portable BPDCMGs such as electric DC ships. The converter modes are analyzed and small-signal models of the converter are extracted. Comprehensive simulation studies are carried out and a BPDCMG laboratory setup is implemented in order to validate the effectiveness of the proposed converter and its hierarchical control strategy. Simulation and experimental results show that using the proposed converter mitigates voltage imbalances. As a result, the system efficiency is improved by using the hierarchical optimal power flow control.

• Applied Biological Chemistry
• /
• 제42권3호
• /
• pp.223-228
• /
• 1999

제주산 궁천조생 온주밀감의 저장효과를 검토하기 위하여 저장 중 각각 $3^{circ}C$, 90%와 85% 상대습도에서 저온저장하였으며, 습도 조절이 안된 상온저장과 비교하였다. 중량감소는 저장 98일까지 각각 90% 습도에서는 3.40%, 85% 습도에서는 6.92%, 상온저장에서는 11.87%로서 습도가 높을수록 중량감소는 적었다. 그러나 90% 습도에서 저장한 감귤은 저장 98일 이후 부패율이 3.87%에서 급격히 증가하여 126일에 48.75%에 이르렀다. 과육율과 가용성고형물은 저장기간 중 큰 변화를 보이지 않았다. 경도는 저장 중 계속하여 감소하였고, 특히 상온저장에서 감소가 심하였다. 산 함량과 비타민 C 변화는 호흡작용에 의해 저장기간이 경과함에 따라 계속하여 감소하였다. 상온저장에서는 저온저장에 비해 착색이 계속 진행됨을 알 수 있었다. 관능평가와 내용성분을 기준한다면 품질 유지를 위해서는 $3^{circ}C$, 85% 상대습도에서 수확후 100일 정도가 조생온주 밀감의 최적 저장기간으로 판단되었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제28권9호
• /
• pp.1281-1287
• /
• 2015

This study was performed to determine the effect of field pea silages which were the organic acid (OA) alternative of oregano and cinnamon essential oils on fermentation quality and aerobic stability. Whole crop pea was harvested at full pod stage and wilted in the laboratory at the 48 h. The chopped pea was mixed and divided into equal portions allocated to five groups: CON (non-treated), distilled water, denoted as control group; OA group, a mixture of 60% formic acid, 20% sodium formate and 20% water applied at a rate of 5 g/kg fresh forage (Silofarm Liquid, Farmavet); origanum (ORE) group, Origanum onites essential oil at 400 mg/kg fresh forage; cinnamon (CIN) group, cinnamon essential oil at 400 mg/kg fresh forage; origanum+cinnamon (ORECIN) group, a mixture of ORE and CIN applied at an equal rate of 400 mg/kg fresh forage. Cinnamon decreased acetic acid (AA), ammonia nitrogen ($NH_3-N$) and weight loss (WL) at the end of 60 days silage. Crude protein (CP) and dry matter (DM) increased by cinnamon essential oil. Yeasts were not detected in any treatments, including the control, after 7 days of air exposure. The $CO_2$ amount decreased and the formation mold was inhibited in the aerobic period by the addition of cinnamon oil. Oregano did not show a similar effect, but when it was used with cinnamon, it showed synergic effect on AA and during aerobic period, it showed antagonistic effect on mold formation and DM losses. It was found in this study that cinnamon can be an alternative to organic acids.