• Title/Summary/Keyword: Mixed-effect model

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Genetic and Environmental Trends for Milk Production Traits in Sheep Estimated with Test-day Model

  • Oravcova, Marta;Pesovicva, Dana
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.8
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    • pp.1088-1096
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    • 2008
  • Data from milk performance testing were used to analyze genetic and environmental trends for purebred Tsigai, Improved Valachian and Lacaune sheep. 103,715 (Tsigai), 212,962 (Improved Valachian) and 2,196 (Lacaune) test-day records gathered by the State Breeding Institute of the Slovak Republic entered the analyses. The respective pedigree data comprised 23,724 (Tsigai), 51,401 (Improved Valachian) and 438 (Lacaune) records. The multiple-trait, mixed model methodology was used to predict the breeding values for daily milk yield, fat and protein content and to estimate the fixed and remaining random effects assumed to affect the above mentioned traits, separately for each breed. The breeding values for daily milk yield were adjusted for 150-day standardized lactation length by multiplying with the constant 150, as the breeding goal of the selection scheme in Slovakian sheep is to increase 150-day milk production and constant heritability throughout the whole lactation is assumed. The genetic trends were expressed as changes in averages of breeding values across birth years of animals. For Tsigai and Lacaune breeds, cumulative genetic changes over the analyzed period were 3.8 and 5.1 kg for 150-day milk, 0 and -0.16% for fat content and 0 and -0.12% for protein content. For Improved Valachian breed, either a low (1.6 kg for 150-day milk yield) or zero (fat and protein content) cumulative genetic change was found. The environmental trends were calculated as averages of solutions for flock-test day effect across years and months in which measurements were taken. A distinctive cyclical pattern which reflected short-time variation in milk production traits was found. Possible explanations for this phenomenon are given and discussed.

Reflection Properties of SiO2/ITO Transparent and Conductive Thin Films for Display (디스플레이용 SiO2/ITO 투명전도막의 반사특성)

  • Shin, Yong-Wook;Kim, Sang-Woo;Yoon, Ki-Hyun
    • Journal of the Korean Ceramic Society
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    • v.39 no.3
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    • pp.233-239
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    • 2002
  • Reflection properties of $SiO_2$/ITO (Indium Tin Oxide) thin films coated for electromagnetic shielding, anti-static and anti-reflection on the front surface in CRT were studied. The behavior of reflectance as a function of thickness of $SiO_2$/ITO was investigated and applied to theoretical anti0reflection model of double layers and three layers. As the thickness of ITO layer increased, the deviation from theoretical value increased because uniformity of film deteriorated by pore. Because of the effect of mixed layer of $SiO_2$ and ITO, experimental reflectance showed better acceptance to the three layer antireflection model of $SiO_2$/$SiO_2$+ITO/ITO than the two layer model. Based on the theoretical antireflection design, the double layer whose thickness of $SiO_2$ and ITO were 90, 65 nm, respectively appear 2.5% in reflectance at standard wavelength, 550 nm. This phenomenon was similar to theoretical reflectance in visual range.

A Study on the Phase Behavior and Stability of the Polar Oil Emulsion System (Polar Oil계 Emulsion의 상거동과 안정성에 관한 연구)

  • Park, Eun-Hee;Chung, Hung-Ho;Kim, Jong-Gyu;Kim, Hyung-Il;Rho, Jae-Seong
    • Applied Chemistry for Engineering
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    • v.8 no.3
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    • pp.510-516
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    • 1997
  • O/W emulsions were prepared by adding water to the solution containing amphiphilic resin and the mixed emulsifier of cetyl alcohol polyoxyethylene(20) sorbitan monooleate. Phase behavoir of these emulsions was studied at various HLB(Hydrophilic Lipophilic Balance) values and temperatures. The polar oil emulsion containing the amphiphilic resin showed improved phase stability at various temperatures. Model compounds which contain one of the functional groups in the amphiphilic resin were used in the polar oil phase in order to study the effect of interaction between the functional group and the emulsifier on the phase stability of emulsion. These model compound emulsions showed the phase stability order of poly(acrylic acid)

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Study of decomposition model for students' understanding the function of mathematics (수학의 기능 이해를 위한 분석적 교수방법의 연구)

  • Byun Du-Won;Seo Jong-Jin;Park Sang-Tae;Ro Young Soon;Kim Yung Hwan;Park Dal-Won
    • Journal of the Korean School Mathematics Society
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    • v.8 no.3
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    • pp.315-325
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    • 2005
  • In school education, mathematics is obviously an independent subject. But the function of mathematics is revealed when it is joined with other subject. For example, when we use mathematics to solve a scientific problem, we can clearly feel the function of mathematics and its roll for science. So, it is general to teach the functions of mathematics by dealing mathematical application. For this method, student mostly pass over that because mathematics is only a tool. Therefore, it is necessary for mathematics part to be separated from mixed application. In this paper, we present a model to contain such an effect.

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The Evaluation on the Environmental Effect of Coal-Ash and Phosphogypsum as the Evapotranspiration Final Cover Material (증발산 원리를 이용한 매립장 최종 복토공법의 복토재로서 석탄재와 인산석고의 환경적 영향 평가)

  • Yu, Chan;Yang, Kee-Sok
    • Journal of the Korean GEO-environmental Society
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    • v.6 no.1
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    • pp.15-21
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    • 2005
  • In this study, the utilization of coal-ash and phosphogypsum was considered as the evapotranspiration final landfill cover(ET cover) material. Cover material considered was the mixture of the weathered granite soil, coal-ash and phosphogypsum and so we sequentially performed the leaching test, column test and field model test to investigate the environmental effects of mixtures of coal-ash and phosphogypsum. In the leaching test, all materials had lower heavy metal concentration than the regulated threshold values. The column test and the review of related regulations were carried out to determine the optimum mixing ratio(OMR) and OMR was soil(4):coal-ash(1): phosphogypsum(1) on the volume base, which was applied to field model test. Field model tests were continued from February to June, 2004 in the soil box that was constructed with cement block. It was verified that coal-ash and phospogypsum mixed with soil was safe environmentally and the mixture of both wastes could improve the water retention capacity of cover materials.

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A Study on Throughput Increase in Semiconductor Package Process of K Manufacturing Company Using a Simulation Model (시뮬레이션 모델을 이용한 K회사 반도체 패키지 공정의 생산량 증가를 위한 연구)

  • Chai, Jong-In;Park, Yang-Byung
    • Journal of the Korea Society for Simulation
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    • v.19 no.1
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    • pp.1-11
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    • 2010
  • K company produces semiconductor package products under the make-to-order policy to supply for domestic and foreign semiconductor manufacturing companies. Its production process is a machine-paced assembly line type, which consists of die sawing, assembly, and test. This paper suggests three plans to increase process throughput based on the process analysis of K company and evaluates them via a simulation model using a real data collected. The three plans are line balancing by adding machines to the bottleneck process, product group scheduling, and reallocation of the operators in non-bottleneck processes. The evaluation result shows the highest daily throughput increase of 17.3% with an effect of 2.8% reduction of due date violation when the three plans are applied together. Payback period for the mixed application of the three plans is obtained as 1.37 years.

CPUE Standardization Considering Spatio-temporal and Environmental Variables of Chub Mackerel Scomber japonicus in Korean Waters (한국 연근해 고등어(Scomber japonicus) 자원의 시공간과 환경요인을 고려한 CPUE 표준화)

  • Moo-Jin Kim;Seokjin Yoon;Hwan-Sung Ji;Minkyoung Bang;Chang Sin Kim;Heejoong Kang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.57 no.5
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    • pp.589-597
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    • 2024
  • The chub mackerel Scomber japonicus is the most important commercial species caught primarily by large purse seine fisheries. The effective management of chub mackerel resources requires a thorough understanding of the current stock status and the factors driving its fluctuations. The catch per unit effort (CPUE) is a crucial index representing the relative abundance of resources, and CPUE standardization was applied using a generalized linear model and generalized linear mixed model (GLMM). This study adopted various explanatory variables including spatiotemporal factors of Year, Month and Area (spatial clustering), and environmental factors of seawater temperature at a depth 50 m ((T50) and Tsushima Warm Current transport (TWC) and catch ratio of chub mackerel (Ratio). The GLMM, which incorporates random effects, was identified as the optimal model. Ratio had the most significant effect on the CPUE, and environmental and spatio-temporal factors had significant influences. Although the nominal CPUE showed an increasing trend across different areas, the standardized CPUE either decreased or exhibited a decreasing rate of increase. These findings serve as fundamental data for stock assessment and contribute to the spatiotemporal and environmentally informed management of chub mackerel resources in Korean waters.

Discount Presentation Framing & Bundle Evaluation: The Effects of Consumption Benefit and Perceived Uncertainty of Quality (묶음제품 가격 할인 제시 프레이밍 효과: 지각된 소비 혜택과 품질 불확실성의 영향을 중심으로)

  • Im, Meeja
    • Asia Marketing Journal
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    • v.14 no.1
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    • pp.53-81
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    • 2012
  • Constructing attractive bundle offers depends on more than an understanding of the distribution of consumer preferences. Consumers are also sensitive to the framing of price information in a bundle offer. In classical economic theory, consumers' utility should not change as long as the total price paid stays same. However, even when total prices are identical, consumers' preferences toward a bundle product could be different depending on the format of price presentation and the locus of price discount. A weighted additive model predicts that the impact of a price discount on the overall evaluation of the bundle will be greater when the discount is assigned to the more important product in the bundle(Yadav 1995). Meanwhile, a reference dependent model asserts that it is better to assign a price discount to a tie-in component that has a negative valuation at its current offer price than to a focal product that has a positive valuation at its current offer price(Janiszewski and Cunha 2004). This paper has expanded previous research regarding price discount presentation format, investigating the reasons for mixed results of prior research and presenting new mechanisms for price discount framing effect. Prior research has hypothesized that bundling is used to sell a tie-in component with an offer price above the consumer's reference price plus a focal product of the same offer price with reference price(e.g., Janiszewski and Cunha 2004). However, this study suggests that bundling strategy can be used for increasing product's attractiveness through the synergy between components even when offer prices of bundle components are the same with reference prices. In this context, this study employed various realistic bundle sets with same price between offer price and reference price in the experiment. Hamilton and Srivastava(2008) demonstrated that when evaluating different partitions of the same total price, consumers prefer partitions in which the price of the high-benefit component is higher. This study determined that their mechanism can be applied to price discount presentation formats. This study hypothesized that price discount framing effect depends not on the negative perception of tie-in component with offer price above reference price but rather on the consumers' perceived consumption benefit in bundle product. This research also hypothesized that preference for low-benefit discount mechanism is that perceived consumption benefit reduces price sensitivity. Furthermore, this study investigated how consumers' concern for quality in a price discount--a factor not considered in previous research--influences price discount framing. Yadav(1995)'s experiment used only one magazine bundle of relatively low quality uncertainty and could not show the influence of perceived uncertainty of quality. This study assumed that as perceived uncertainty of quality increases, the price sensitivity mechanism for assigning the discount to low-benefit will increase. Further, this research investigated the moderating effect of uncertainty of quality in price discount framing. The results of the experiment showed that when evaluating different partitions of the same total price and the same amount of discounts, the partition that discounts in the price of low benefit component is preferred to the partition that decreases the price of high benefit component. This implies that price discount framing effect depends on the perceived consumption benefit. The results also demonstrated that consumers are more price sensitive to low benefit component and less price sensitive to high benefit component. Furthermore, the results showed that the influence of price discount presentation format on the evaluation of bundle product varies with the perceived uncertainty of quality in high consumption benefit. As perceived uncertainty of quality gradually increases, the preference for discounts in the price of low consumption benefit decreases. Besides, the results demonstrate that as perceived uncertainty of quality gradually increases, the effect of price sensitivity in consumption benefit also increases. This paper integrated prior research by using a new mechanism of perceived consumption benefit and moderating effect of perceived quality uncertainty, thus providing a clearer explanation for price discount framing effect.

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The Effect of Buthus martensi Karsch Herbal-acupuncture on Immune Responses to Adjuvant Induced Arthritis in Rats (전갈약침이 adjuvant 유발 흰쥐의 관절활액막내 cytokine과 prostaglandin E2에 미치는 영향)

  • Song, In-Kwang;Choi, Woo-Shik;Park, Joon-Sung;Lee, Seung-Deok;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.19 no.2
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    • pp.177-188
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    • 2002
  • Objective : The purpose of this study is to investigate the immunohistological effect of Buthus martensi Karsch Herbal-acupuncture in treating the arthritis, performed several experimental items : those are paw edema, $IL-1{\beta}$, IL-6, IL-8, $TNF-{\alpha}$ and $PGE_2$. Methods : All the male Sprague Dawley rats used in this study were bred and maintaned in our pathogen-free rat colony and were 8 weeks of age at the start of to experiment. The experimental model of arthritis was induced by injection of $50{\mu}g/{\mu}{\ell}$ adjuvant(mineral oil mixed Mycobacterium butyricum). Buthus martensi Karsch Herbal-acupuncture was injected into ST36(足三里) of rats daily for 21 days. Immunohistological analysis was carried out to assess paw edema, $IL-1{\beta}$, IL-6, IL-8, $TNF-{\alpha}$ and $PGE_2$ expression in synovial membrane and sera Buthus martensi Karsch Herbal-acupuncture injected. Results : Buthus martensi Karsch Herbal-acupuncture group showed a decrease with statistical significance, in paw edema, $IL-1{\beta}$, IL-6, IL-8, $TNF-{\alpha}$ and $PGE_2$ in synovial membrane and sera compared with control group. Conclusion : Buthus martensi Karsch Herbal-acupuncture stimulation inhibited the development of immunity to adjuvant induced arthritis in rats. Thus, Buthus martensi Karsch Herbal-acupuncture may have preventive effects on autoimmune inflammatory joint diseases as arthritis. The effect of Buthus martensi Karsch Herbal-acupuncture on the immune function and the disease activity in patients with arthritis warrants further investigation.

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Analyzing the Effect of an Extreme Turbidity Flow Event on the Dam Reservoirs in North Han River Basin (북한강 수계 대규모 탁수사상 발생에 의한 댐 저수지의 탁수 영향 분석)

  • Park, Hyung-Seok;Chung, Se-Woong;Choung, Sun-a
    • Journal of Korean Society on Water Environment
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    • v.33 no.3
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    • pp.282-290
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    • 2017
  • A long-term resuspension of small particles, called persistent turbidity, is one of the most important water quality concerns in the dam reservoirs system located in North Han River. Persistent turbidity may incur aesthetic nuisance and harmful effect on the ecosystem health, in addition to elevated water treatment costs for the drinking water supply to the Seoul metropolitan area. These sufferings have been more intensified as the strength and frequency of rainfall events increase by climate change in the basin. This study was to analyze the effect of an extreme turbidity flow event that occurred in 2006 on the serial reservoirs system (Soyang-Uiam-Cheongpyung-Paldang) in North Han River. The CE-QUAL-W2 model was set up and calibrated for the river and reservoirs system using the field data obtained in 2006 and 2007. The results showed that Soyang Reservoir released turbid water, which was classified as the TSS concentration is greater than 25 mg/L, for 334 days with peak TSS of 264.1 mg/L after the extreme flood event (592.7 mm) occurred between July 10 and 18 of 2006. The turbid water departed from Soyang Reservoir reached at the most downstream Paldang Reservoir after about 20 days and sustained for 41 days, which was validated with water treatment plant data. Since the released water from Soyang Reservoir had low water temperature and high TSS, an underflow formed in the downstream reservoirs and vertically mixed at Paldang Reservoir due to dilution by the sufficient inflow from South Han River.