• 마이크로전자및패키징학회지
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• 제14권3호
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• pp.29-36
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• 2007

본 논문에서는 펨토초 레이저를 사용하여 정밀하고 효과적인 레이저 어블레이션 작업이 가능한지를 확인하기위한 수치 해석 및 가공 작업을 수행하였다. 이를 위하여 Si 재료 내부의 에너지 전달 메커니즘에 대한 수치해석을 실시하였으며, Si 웨이퍼에 각각 다른 조건으로 적용된 레이저 플루언스 값으로 $100\;{\mu}m$ 직경의 미세 관통 홀을 형성한 후, 광학현미경과 3차원 표면 형상 측정 장비를 사용하여 형성된 미세 관통 홀의 가공성과 열영향부의 발생 정도를 관찰하고 분석하였다. 실험 결과를 통해 레이저 플루언스 조건에 따른 열영향부의 발생 정도를 분석하였으며, 또한 최소한의 열영향부를 가지며 우수한 홀 가공성을 보이는 최적의 미세 관통 홀 가공 조건을 도출하였다.

• Steel and Composite Structures
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• 제22권4호
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• pp.797-820
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• 2016

This paper simulates the hysteretic behavior of steel reinforced recycled concrete (SRRC) columns under cyclic loads using OpenSees software. The effective fiber model and displacement-based beam-column element in OpenSees is applied to each SRRC columns. The Concrete01 material model for recycled aggregate concrete (RAC) and Steel02 material model is proposed to perform the numerical simulation of columns. The constitutive models of RAC, profile steel and rebars in columns were assigned to each fiber element. Based on the modelling method, the analytical models of SRRC columns are established. It shows that the calculated hysteresis loops of most SRRC columns agree well with the test curves. In addition, the parameter studies (i.e., strength grade of RAC, stirrups strength, steel strength and steel ratio) on seismic performance of SRRC columns were also investigated in detail by OpenSees. The calculation results of parameter analysis show that SRRC columns suffered from flexural failure has good seismic performance through the reasonable design. The ductility and bearing capacity of columns increases as the increasing magnitude of steel strength, steel ratio and stirrups strength. Although the bearing capacity of columns increases as the strength grade of RAC increases, the ductility and energy dissipation capacity decreases gradually. Based on the test and numerical results, the flexural failure mechanism of SRRC columns were analysed in detail. The computing theories of the normal section of bearing capacity for the eccentrically loaded columns were adopted to calculate the nominal bending strength of SRRC columns subjected to vertical axial force under lateral cyclic loads. The calculation formulas of horizontal bearing capacity for SRRC columns were proposed based on their nominal bending strength.

• Asian-Australasian Journal of Animal Sciences
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• 제11권6호
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• pp.725-731
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• 1998

Nine crossbred female pigs fitted with the bladder catheters were used to investigate the effects of dietary protein form on the efficiency of absorbed nitrogen for nitrogen retention in growing pigs. Combinations of the main protein sources were corn-soybean meal (CSM; slow + slow absorption rate form), corn-hydrolyzed casein (CAS; slow + rapid absorption rate form) and corn-porcine plasma (CPL; slow + intermediate absorption rate form). All experimental diets were formulated to be isonitrogenous (CP 11%) and isocaloric (3.5 Mcal/kg) and synthetic amino acids were added to the diet as required to maintain an equivalent amino acid profile among diets. Fecal digestibility of nitrogen was not different among treatments (p > 0.10). Ingested nitrogen was absorbed with an apparent efficiency of 82% to 84%. Mean nitrogen retention in pigs fed the CSM diet was as high as for pigs fed the CPL diet (0.74 g N/kg $BW^{0.75}$ per d), which was higher than the N retention rate in pigs fed CAS diet (0.68 g/kg $BW^{0.75}$ per d; P < 0.05). Apparent biological values (ABV = 100 ${\times}$ N retention/absorbed nitrogen) were 63.3%, 58.0% and 61.6% for CSM, CAS, and CPL groups, respectively (p < 0.05). There was no difference in mean energy digestibility among treatments. The efficiency of absorbed lysine utilization was significantly different among treatments (p < 0.05). Pigs fed the CAS diet were inferior to counterparts on the other diets in utilizing absorbed lysine. The ratios of free (and small peptide-bound) to protein-bound amino acids in CSM diet differed considerably from the CAS diet. This may affect the efficiency of amino acids utilization for nitrogen retention if hydrolyzed and intact amino acid pools reach the blood at different times.

• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.463-472
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• 2003

Cassava (Manihot esculenta, Crantz), an annual tropical tuber crop, was nutritionally evaluated as a foliage for ruminants, especially dairy cattle. Cultivation of cassava biomass to produce hay is based on a first harvest of the foliage at three months after planting, followed every two months thereafter until one year. Inter-cropping of leguminous fodder as food-feed between rows of cassava, such as Leucaena leucocephala or cowpea (Vigna unculata), enriches soil fertility and provides additional fodder. Cassava hay contained 20 to 25% crude protein in the dry matter with good profile of amino acids. Feeding trials with cattle revealed high levels of DM intake (3.2% of BW) and high DM digestibility (71%). The hay contains tannin-protein complexes which could act as rumen by - pass protein for digestion in the small intestine. As cassava hay contains condensed tannins, it could have subsequent impact on changing rumen ecology particularly changing rumen microbes population. Therefore, supplementation with cassava hay at 1-2 kg/hd/d to dairy cattle could markedly reduce concentrate requirements, and increase milk yield and composition. Moreover, cassava hay supplementation in dairy cattle could increase milk thiocyanate which could possibly enhance milk quality and milk storage, especially in small holder-dairy farming. Condensed tannins contained in cassava hay have also been shown to potentially reduce gastrointestinal nematodes in ruminants and therefore could act as an anthelmintic agent. Cassava hay is therefore an excellent multi-nutrient source for animals, especially for dairy cattle during the long dry season, and has the potential to increase the productivity and profitability of sustainable livestock production systems in the tropics.

• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1296-1303
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• 2000

A series of four experiments was conducted to compare nutritional values of decorticated sunflower meals against soybean meal, in diets for pigs from weaning (Exp. 1 and 2) to finishing (Exp. 3 and 4). All experimental diets were prepared compensating for the energy content by using vegetable oil and the lysine content was matched using synthetic L-Lysine HCl. Twenty-one day old pigs were fed either corn-soybean meal based diet (CSBM) or corn- twice-decorticated sunflower meal based diet (CDSM) for four weeks (Exp. 1). There was no difference in performances between treatment groups. In Exp. 2, corn-non-decorticated sunflower meal based diet (CNSM) was added to the existing two treatments. Twenty-one day old pigs were fed three experimental diets for four weeks. Pigs fed CNSM had a lower weight gain and feed intake than other treatments (p<0.05). There was no difference between pigs fed CSBM and CDSM (Exp. 2). Growth performance of growing pigs was also greater (p<0.05) in pigs fed corn starch-twice- decorticated sunflower meal based diet (CSDSM) than pigs fed corn starch-non-decorticated sunflower meal based diet (CSNSM) during the eight week feeding trial (Exp. 3). There was no difference between pig fed corn starch-soybean meal based diet (CSSBM) and CSDSM (Exp. 3). In Exp. 4, growing pigs were fed three experimental diets (CSBM, CDSM, and barley-twice- decorticated sunflower meal based diet; BDSM) until the slaughter. There was no difference in growth performance of pigs during growing and finishing periods among treatments. However, pigs fed CSBM had a higher carcass dressing percentage (p<0.05) than pigs fed CDSM and BDSM. Pigs fed BDSM diet had a lower fat tissue percentage than other groups (p<0.05). The twice-decorticated sunflower meal can be used as a substitute for soybean meal in pig diets. The performances of piglets and growing-finishing pigs were not affected when soybean meal was replaced by twice-decorticated sunflower meal. This substitution needs the contribution of synthetic lysine and vegetable oil as sources of complementary nutrients to match the nutrient profile.

• 대기
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• 제18권4호
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• pp.441-458
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• 2008

A TP/WVP-3000A, ground-based microwave radiometer, that was first introduced to South Korea has been operated since August 22, 2007 at the National Center for Intensive Observation of Severe Weathers (NCIO). Using the dual-band, the radiometer provides temperature and humidity soundings from the surface up to 10 km height with the high-temporal resolution of a few minutes. In this study, the performance of the radiometer on the predictability of the high impact weathers was evaluated and various practical applications were investigated. To verify the retrieved profile data from the radiometer, temperature and relative humidity soundings are compared with those from the rawinsonde launched at the NCIO and Gwangju station. The root mean squared errors for temperature and relative humidity soundings were smaller under rainy weather conditions. The correlation coefficient between PWVs (Precipitable Water Vapors) obtained from the radiometer and Global Positioning System satellite at Mokpo station is 0.92 on average. In order to investigate the structure and characteristics of precipitation, stability indexes related to rainfall such as the Convective Available Potential Energy (CAPE), K-index, and Storm RElative Helicity (SREH) were calculated using windprofiler at the NCIO from 14 to 16 September, 2007. CAPE and K-index tended to be large when the thermodynamic unstability was strong. On the other hand, SREH index was dominantly large when the dynamic unstability was strong due to the passage of the typhoon 'Nari'.

• 한국대기환경학회지
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• 제23권6호
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• pp.718-726
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• 2007

There are many varieties of asbestos: chrysotile, crocidolite, amosite, tremolite, actinolite, and anthophylite. These are widely used in construction materials, brake lining, textile, and so on. Even though non-asbestos fibers such as glassfiber and rockwool have manufactured because asbestos causes asbestosis, lung cancer, mesothelioma, etc., some bad effects of non-asbestos have been also reported. PCM (phase contrast microscopy) and PLM (polarized light microscopy) have been used to qualitatively analyze asbestoses. These techniques have serious drawbacks when identifying and separating various asbestoses. Recently scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDX) has been known as an useful tool to analyze airborne particle since it provides physical and chemical information simultaneously. The purpose of the study was to classify both asbestos and non-asbestos fibers and finally to develop their source profiles by using the SEM/EDX. The source profiles characterized by 6 different types of asbestos fibers and 2 types of non-asbestos fibers had been developed by analyzing a total of 380 fibers. Analytical parameters used in this study were length, width, aspect ratio, and shape as physical information, and Na, Mg, Al, Si, K, Ca, Cr, Mn, Fe, and Cu as chemical information. All the parameters were intensively reviewed.

• Toxicological Research
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• 제31권1호
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• pp.61-68
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• 2015

The objective of this study was to obtain single oral dose toxicity information for concentrated and lyophilized powder of blue honeysuckle (Lonicera caerulea L., Caprifoliaceae; BHcL) in female and male ICR mice to aid in the process of developing natural origin medicinal ingredients or foods following proximate analysis and phytochemical profile measurement. The proximate analysis revealed that BHcL had an energy value of 3.80 kcal/g and contained 0.93 g/g of carbohydrate, 0.41 g/g of sugar, 0.02 g/g of protein, and 0.20 mg/g of sodium. BHcL did not contain lipids, including saturated lipids, trans fats, or cholesterols. Further, BHcL contained 4.54% of betaine, 210.63 mg/g of total phenols, 159.30 mg/g of total flavonoids, and 133.57 mg/g of total anthocyanins. Following administration of a single oral BHcL treatment, there were no treatment-related mortalities, changes in body weight (bw) or organ weight, clinical signs, necropsy or histopathological findings up to 2,000 mg/kg bw, the limited dosage for rodents of both sexes. We concluded that BHcL is a practically non-toxic material in toxicity potency.

• Food Quality and Culture
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• 제3권2호
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• pp.53-58
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• 2009

This study was conducted to investigate the quality characteristics of frozen stored mungbean starch gels added with sucrose fatty acid ester (SE). The study showed a delay of gelatinization of mungbean starch by SE addition through the measurements conducted by using Rapid Visco Analyzer (RVA) and Differential Scanning Calorimeter (DSC). In the color of SE added frozen stored gels, lightness (L) and yellowness (b) values were increased compared to those of values measured from freshly prepared gel, whereas redness (a) value was decreased. The addition of 1% SE on mungbean starch gel prevented the color change during frozen storage. Rupture stress and rupture energy of frozen stored gel was higher than those of freshly prepared gel, whereas rupture strain of frozen stored gel was lower than that of freshly prepared gel. The addition of 1% SE on mungbean starch gel prevented the change of rupture characteristics during frozen storage. Texture profile analysis(TPA) characteristics revealed a significant change of the gel texture during frozen storage by showing an increase of hardness of the frozen stored gels compared to the freshly prepared gels with newly discovered fracturability, which resulted to show a large difference of gel texture by showing the disappearance of adhesiveness and large reduction of cohesivenes. The addition of 1% SE on mungbean starch gel prevented the change of TPA characteristics during frozen storage. Scanning electron micrographs showed that network structure of frozen stored gel was more rough than that of freshly prepared gel, and the addition of 1% SE on mungbean starch gel could suppress the breakdown of network structure. Thus the addition of 1.0% SE on mungbean starch gel was appropriate method for remaining gel characteristics during frozen storage.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2007년도 가을 학술발표논문집 Vol.34 No.2 (D)
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• pp.240-243
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• 2007

Geographic routing has been considered as an efficient simple, and scalable routing protocol for wireless sensor networks since it exploits pure location information instead of global topology information to route data packets. Geographic routing requires the sources nodes to be aware of the location of the sinks. In this paper, we propose a scheme named Sink Location Service for geographic routing in wireless Sensor Networks, in which the source nodes can get and update the location of sinks with low overhead. In this scheme, a source and a sink send data announcement and query messages along two paths respectively by geographic routing. The node located on the crossing point of the two paths informs the source about the location of the sink. Then the source can send data packet to the sink by geographic routing. How to guarantee that these two paths have at least one crossing point in any irregular profile of sensor network is the challenge of this paper.