• Korean Journal of Weed Science
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• v.30 no.2
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• pp.103-110
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• 2010

This experiment was conducted to investigate seedling emergence and early growth of Monochoria vaginalis and Scirpus juncoides in the controlled-environment chamber maintained at different temperatures. Non-linear regression analyses of observed data against effective accumulated temperature (EAT) with the Gompertz and logistic models showed that the Gompertz and logistic models worked well in describing seedling emergence and early growth of both weed species, respectively, regardless of temperature. EATs required for 50% of the maximum seedling emergence and the maximum leaf number of M. vaginalis were estimated to be 69.3 and $131^{\circ}C$, respectively, while those of S. juncoides were 94.8 and $137^{\circ}C$, respectively. Models developed in this study thus were used to predict seedling emergence and early growth under elevated temperature condition. If rotary tillage with water is made on 27 May under $+3^{\circ}C$ elevated temperature condition, dates for 50% of the maximum seedling emergence and 4 leaf stage were predicted to be 1 June and 15 June for M. vaginalis and 3 June and 14 June for S. juncoides, respectively. As compared with current temperature, these dates are 1-2 days earlier for the seedling emergence and 3 days earlier for the early growth, suggesting that earlier application of herbicides is required for effective control of M. vaginalis and S. juncoides under elevated temperature condition in the future.

• Animal Bioscience
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• v.36 no.8
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• pp.1263-1273
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• 2023

Objective: This study was conducted to evaluate the effects of crude protein (CP) levels on the physiological response, reproductive performance, blood profiles, milk composition and odor emission in gestating sows. Methods: Seventy-two multiparous sows (Yorkshire×Landrace) of average body weight (BW), backfat thickness, and parity were assigned to one of six treatments with 10 or 11 sows per treatment in a completely randomized design. Experimental diets with different CP levels were as follows: i) CP11, corn-soybean-based diet containing 11% CP; ii) CP12, corn-soybean-based diet containing 12% CP; iii) CP13, corn-soybean-based diet containing 13% CP; iv) CP14, corn-soybean-based diet containing 14% CP; v) CP15, corn-soybean-based diet containing 15% CP; and vi) CP16: corn-soybean-based diet containing 16% CP. Results: There was no significant difference in the performance of sow or piglet growth when sows were fed different dietary protein levels. Milk fat (linear, p = 0.05) and total solids (linear, p = 0.04) decreased as dietary CP levels increased. Increasing dietary CP levels in the gestation diet caused a significant increase in creatinine at days 35 and 110 of gestation (linear, p = 0.01; linear, p = 0.01). The total protein in sows also increased as dietary CP levels increased during the gestation period and 24 hours postpartum (linear, p = 0.01; linear, p = 0.01). During the whole experimental period, an increase in urea in sows was observed when sows were fed increasing levels of dietary CP (linear, p = 0.01), and increasing blood urea nitrogen (BUN) concentrations were observed as well. In the blood parameters of piglets, there were linear improvements in creatinine (linear, p = 0.01), total protein (linear, p = 0.01), urea (linear, p = 0.01), and BUN (linear, p = 0.01) with increasing levels of dietary CP as measured 24 hours postpartum. At two measurement points (days 35 and 110) of gestation, the odor gas concentration, including amine, ammonia, and hydrogen sulfide, increased linearly when sows fed diets with increasing levels of dietary CP (linear, p = 0.01). Moreover, as dietary CP levels increased to 16%, the odor gas concentration was increased with a quadratic response (quadratic, p = 0.01). Conclusion: Reducing dietary CP levels from 16% to 11% in a gestating diet did not exert detrimental effects on sow body condition or piglet performance. Moreover, a low protein diet (11% CP) may improve dietary protein utilization and metabolism to reduce odor gas emissions in manure and urine in gestating sows.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1076-1080
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• 2003

$CO_2$ uptake of vegetation is one of the important variables in order to estimate photosynthetic activity, plant growth and carbon budget estimations. The objective of this research was to develop a new estimation method of $CO_2$ uptake of vegetation based on airborne hyperspectral remote sensing measurements in combination with a photosynthetic rate curve model. In this study, a compact airborne spectrographic imager (CASI) was used to obtain image over a field that had been set up to study the $CO_2$ uptake of corn on August 7, 2002. Also, a field survey was conducted concurrently with the CASI overpass. As a field survey, chlorophyll a content, photosynthetic rate curve, Leaf area, dry biomass and light condition were measured. The developed estimation method for $CO_2$ uptake consists of three major parts: a linear mixture model, an enhanced big leaf model and a photosynthetic rate curve model. The Accuracy of this scheme indicates that $CO_2$ uptake of vegetation could be estimated by using airborne hyperspectral remote sensing data in combination with a physiological model.

• Journal of Animal Science and Technology
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• v.58 no.11
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• pp.39.1-39.12
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• 2016

Background: The current study investigates the anti-stress effects of clove (Eugenia caryophyllus) extracts (0, 200, 400, and 600 mg/kg) on serum antioxidant biomarkers, immune response, immunological organ growth index, and expression levels of acute phase proteins (APPs); ovotransferrin (OVT), ceruloplasmin (CP), ceruloplasmin (AGP), C-reactive protein (CRP), and serum amyloid-A (SAA) mRNA in the immunological organs of 63-d-old male black-meated Silkie fowls subjected to 21 d chronic heat stress at $35{\pm}2^{\circ}C$. Results: The results demonstrated that clove extract supplementation in the diet of Silkie fowls subjected to elevated temperature (ET) improve growth performance, immune responses, and suppressed the activities of glutathion peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), and thioredoxin reductase (TXNRD); reduced serum malonaldehyde (MDA) and glutathione (GSH) concentrations when compared with fowls raised under thermoneutral condition (TC). Upon chronic heat stress and supplementation of clove extracts, the Silkie fowls showed a linear increase in GSH-Px, SOD, CAT, and TXNRD activities (P = 0.01) compared with fowls fed diets without clove extract. ET decreased (P < 0.05) the growth index of the liver, spleen, bursa of Fabricius and thymus. However, the growth index of the liver, spleen, bursa of Fabricius and thymus increased significantly (P < 0.05) which corresponded to an increase in clove supplemented levels. The expression of OVT, CP, AGP, CRP, and SAA mRNA in the liver, spleen, bursa of Fabricius and thymus were elevated (P < 0.01) by ET compared with those maintained at TC. Nevertheless, clove mitigates heat stress-induced overexpression of OVT, CP, AGP, CRP and SAA mRNA in the immune organs of fowls fed 400 mg clove/kg compared to other groups. Conclusions: The results showed that clove extracts supplementation decreased oxidative stress in the heat-stressed black-meated fowls by alleviating negative effects of heat stress via improvement in growth performance, antioxidant defense mechanisms, immunity, and regulate the expression of acute phase genes in the liver and immunological organs.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.16-24
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• 2009

In this study, fatigue crack growth rate of a cracked railway bogie frame under variable amplitude loading is predicted by applying linear elastic fracture mechanics. For this purpose, we find the critical points by reference surveying on cracked railway bogie frames. And we make an effective load history by synthesizing the dynamic load measured from the critical points of railway bogie frame during commercial line operation and the static load calculated from structural analysis. Crack growth analyses are performed at the 3 critical points under the commercial operation loading condition by assuming an initial crack size as 40 mm. and the results are compared with the experimental results from Japanese railway bogie frame crack growth case. From the analysis results, we find that around 500,000 km operating distance is necessary to bring crack growth from the initial crack to unstable crack. And it takes around 3.8 normal operating years. We conclude that it is enough time to detect the crack between normal maintenance period.

• Child Health Nursing Research
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• v.24 no.4
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• pp.496-505
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• 2018

Purpose: The purpose of this study was to examine changes in the self-rated health of adolescents and to identify its predictors using longitudinal data from the KCYPS. Methods: A sample of 2,351 adolescents who were in the first grade of middle school in 2010 was analyzed. The study employed latent growth analysis using data from 2010 to 2016. Results: Results indicated that self-rated health of adolescents increased, following the form of a linear function. The analyses revealed that adolescent self-perception of health were conceptualized not only by their health-related behaviors, but also by personal, socioeconomic and psychological factors. Specifically, physical activity, passive leisure time activities, gender (initial: b=-.060, slope: b=.030), place of residence (initial: b=-.079), self-rated economic condition (b=.098), working status of mother (b=.016), monthly family income (b=-.001), aggression (b=.061), depression (initial: b=-.104, slope: b=.012), stress (initial: b=-.172, slope: b=.014, ego-resiliency (initial: b=.197, slope: b=-.021), and self-esteem (initial: b=.106, slope: b=-.017) had significant effects on the overall linear change of self-rated health (p<.05 for all estimators above). Conclusion: The findings of this study suggest that adolescents' self evaluation of their health is shaped by their total sense of functioning, which includes individual, health-related behavioral, socioeconomic, and psychological factors.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.14 no.3
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• pp.95-100
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• 2004

This paper reports a potential problem in the electrical performance of the silicide film to silicon contacts with respect to the scaling trend in integrated circuit (IC) devices. The effects of elastic strain on the agglomeration of the coherent silicide film embedded in an infinite matrix are studied employing continuum linear elasticity and finite-difference numerical method. The interface atomic diffusion is taken to be the dominant transport mechanism where both capillarity and elastic strain are considered for the driving forces. Under plane strain condition with elastically homogeneous and anisotropic system with cubic symmetry, the dilatational misfit and the tetragonal misfit in the direction parallel to the film thickness are considered. The numerical results on the shape evolution agree with the known trend that the equilibrium aspect ratio of the film increases with the elastic strain intensity. When the elastic strain intensity is taken to be only a function of the film size, the flat film morphology with a large aspect ratio becomes increasingly unstable since the equilibrium aspect ratio decreases, as the film scales. The shape evolution results in a large decrease in contact to silicon area, and may deteriorate the electrical performances.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.375-375
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• 2007

In the conventional crystallization method, thepoly-Si TFTs show poor device-to-device uniformity because of the random location of the grain boundaries. However, our new crystallization method introduced in this paper employed substrate-embedded seeds on the highly ordered anodic alumina template to control both the location of seeds and the number of grain boundaries intentionally. In the process of excimer laser crystallization (ELC), a-Si film deposited on the anodic alumina by low pressure chemical vapor deposition (LPCVD) is transformed into fine poly-Si grains by explosive crystallization (XC) prior to primary melting. At the higher energy density, the film is nearly completely melted and laterally grown by super lateral growth (SLG) from remained small part of the fine poly-Si grains as seeds at the Si/anodic alumina interface. Resultant grain boundaries have almost linear functions of the number of seeds in concavities of anodic alumina which have a constant spacing. It reveals the uniformity of. device can be enhanced prominently by controlling location and size of pores which contains fine poly~Si seeds under artificial anodizing condition.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.2
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• pp.173-183
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• 1998

An optimization procedure to find the inlet concentration profile that yields the most uniform deposition rate in a cylindrical CVD chamber has been developed. Assuming that the chemical reaction time is negligibly small, a SIMPLE based finite-volume method is adopted to solve the fully elliptic equations for momentum, temperature, and concentration. The inlet concentration profile is expressed by a linear combination of Chebyshev polynomials and the coefficients of which are determined by the local random search technique. It is shown that the present method is very effective in improving the uniformity of the deposition rate, especially when Re is high and/or the wafer is placed close to the inlet. The optimal profiles have been obtained for various Re, Gr, and geometry combinations.

• Korean Journal of Plant Resources
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• v.21 no.3
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• pp.210-215
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• 2008

Gene-expression analysis is increasingly important in biological research, with real-time reverse PCR (RTPCR) becoming the method of choice for high-throughput and accurate expression profiling of selected genes. However, this technique requires important preliminary work for standardizing and optimizing the many parameters involved in the analysis. Plant stress studies are more and more based on gene expression. The analysis of gene expression requires sensitive and reproducible measurements for specific mRNA sequence. Several genes are regulated in response to abitoic stresses, such as salinity, and their gene products function in stress response and tolerance. The design of the primers and TaqMan probes for real-time PCR assays were carried out using the Primer $Express^{TM}$ software 3.0. The PCR efficiency was estimated through the linear regression of the dilution curve. To understand the expression pattern of various genes under salt stressed condition, we have developed a unique public resource of 9 stress-related genes in poplar. In this study, real-time RT-PCR was used to quantify the transcript level of 10 genes (9 stress-related genes and 1 house keeping gene) that could play a role in adaptation of Populus davidiana. Real-time RT-PCR analyses exhibited different expression ratios of related genes. The data obtained showed that determination of mRNA levels could constitute a new approach to study the stress response of P. davidiana after adaptation during growth in salinity condition.