• Title/Summary/Keyword: k-C model

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A Model to Explain Temperature Dependent Systemic Infection of Potato Plants by Potato virus Y

  • Choi, Kyung San;Toro, Francisco del;Tenllado, Francisco;Canto, Tomas;Chung, Bong Nam
    • The Plant Pathology Journal
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    • v.33 no.2
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    • pp.206-211
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    • 2017
  • The effect of temperature on the rate of systemic infection of potatoes (Solanum tuberosum L. cv. Chu-Baek) by Potato virus Y (PVY) was studied in growth chambers. Systemic infection of PVY was observed only within the temperature range of $16^{\circ}C$ to $32^{\circ}C$. Within this temperature range, the time required for a plant to become infected systemically decreased from 14 days at $20^{\circ}C$ to 5.7 days at $28^{\circ}C$. The estimated lower thermal threshold was $15.6^{\circ}C$ and the thermal constant was 65.6 degree days. A systemic infection model was constructed based on experimental data, using the infection rate (Lactin-2 model) and the infection distribution (three-parameter Weibull function) models, which accurately described the completion rate curves to systemic infection and the cumulative distributions obtained in the PVY-potato system, respectively. Therefore, this model was useful to predict the progress of systemic infections by PVY in potato plants, and to construct the epidemic models.

$^{13}C$ Spin-Lattice Relaxation Study of Segmental Motions in n-alkanes: n-Undecane and n-Dodecane

  • Min, Buem-Chan;Lee, Jo-Woong
    • Journal of the Korean Magnetic Resonance Society
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    • v.2 no.1
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    • pp.1-23
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    • 1998
  • The motions of carbon-chain backbone in n-undecance and n-dodecane dissolved in CDCl3 are investigated by 13C NMR relaxation study. For this purpose a model of C - C backbone motions for these molecules is introduced that takes into account the cooperativities between rotations about two $\beta$-coupled C - C bonds. In this model it is assumed that the major conformational interconversions occurring in the inner part of the chain involve the type II jumps only, although at terminal part of the chain both type II and type III motions are assumed to take place. Information of the rate constants of these conformational transitions could be extracted by comparing the T1's calculated on the basis of the assumed model with those observed over the temperature range of 248 - 308 K. The calculations were performed according to the method proposed by Wittebort and Szabo. The activation energies, ranging from ca 12 to 20 kJ/mol, could be obtained from the Arrhenius plots of these calculated rate constants.

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A Study on V-C Interoperability Test and Methodology of V-C Interoperation Analysis for Next Generation Maritime Warfighting Experimentation Systems (차세대 해상전투실험체계 구현을 위한 V-C 연동실험 및 연동분석 방법론 연구)

  • Shin, Hyunsoo;Kim, Junghoon;Choi, Bongwan;Yim, Dongsoon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.19 no.1
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    • pp.84-94
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    • 2016
  • The warfighting experimentation is the most important for the weapon acquisition process because the warfighting experimentation shall support the operation effectiveness as well as acquisition logicality. Therefore, ROK Navy is starting to set up the next generation warfighting experimentation systems. According to literature studies, there have been many studies regarding the interoperability of Simulators(Virtual) and Exercising models(Constructive), but not for studies regarding interoperability between Simulators(Virtual) and Analysis models(Constructive) that is the core component of next generation maritime warfighting experimentation systems. This study is dealing with the V-C(Analysis model) interoperability test and methodology of interoperation analysis. The purpose of the study is to provide the new analysis methodology through V-C(Analysis model) interoperation, which can be applied for the concept of operations(CONOPS) of next generation maritime warfighting experimentation systems. In addition to that, the study validates the suggested analysis methodology by the case study of a naval operation.

Comparison Study of Prediction Models for Hot Deformation Behavior of Tool Steel (공구강의 고온 변형 거동 예측을 위한 모델 비교 연구)

  • Kim, Keunhak;Park, Dongsung;Jun, Joong-Hwan;Lee, Min-Ha;Lee, Seok-Jae
    • Journal of the Korean Society for Heat Treatment
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    • v.31 no.4
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    • pp.180-186
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    • 2018
  • High temperature flow behaviors of Fe-Cr-Mo-V-W-C tool steel were investigated using isothermal compression tests on a Gleeble simulator. The compressive test temperature was varied from 850 to $1,150^{\circ}C$ with the strain rate ranges of 0.05 and $10s^{-1}$. The maximum height reduction was 45%. The dynamic softening related to the dynamic recrystallization was observed during hot deformation. The constitutive model based on Arrhenius-typed equation with the Zener-Hollomon parameter was proposed to simulate the hot deformation behavior of Fe-Cr-Mo-V-W-C steel. An artificial neural network (ANN) model was also developed to compare with the constitutive model. It was concluded that the ANN model showed more accurate prediction compared with the constitutive model for describing the hot compressive behavior of Fe-Cr-Mo-V-W-C steel.

Association of DR4 (TRAIL-R1) Polymorphisms with Cancer Risk in Caucasians: an Updated Meta-analysis

  • Chen, Wei;Tang, Wen-Ru;Zhang, Ming;Chang, Kwenjen;Wei, Yun-Lin
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2889-2892
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    • 2014
  • Death receptor 4 (TRAIL-R1 or DR4) polymorphisms have been associated with cancer risk, but findings have been inconsistent. To estimate the relationship in detail, a meta-analysis was here performed. A search of PubMed was conducted to investigate the association between DR4 C626G, A683C and A1322G polymorphisms and cancer risk, using odds ratios (ORs) with 95% confidence intervals. The results suggested that DR4 C626G and A683C polymorphisms were indeed associated with cancer risk (for C626G, dominant model, OR 0.991, 95%CI 0.866-1.133, p=0.015; for A683C, additive model, OR=1.140, 95%CI: 0.948-1.370, p=0.028; dominant model, OR=1.156, 95%CI: 0.950-1.406, p=0.080) in the Caucasian subgroup. However, the association was not significant between DR4 polymorphism A1322G with cancer risk in Caucasians (For A1322G, additive model: OR 1.085, 95%CI 0.931-1.289, p=0.217; dominant model: OR 1.379, 95%CI 0.934-2.035, p=0.311; recessive model: OR 1.026, 95%CI 0.831-1.268 p=0.429.). In summary, our finding suggests that DR4 polymorphism C626G and A683 rather than A1322G are associated with cancer risk in Caucasians.

Development of Predictive Growth Model of Vibrio parahaemolyticus Using Mathematical Quantitative Model (수학적 정량평가모델을 이용한 Vibrio parahaemolyticus의 성장 예측모델의 개발)

  • Moon, Sung-Yang;Chang, Tae-Eun;Woo, Gun-Jo;Shin, Il-Shik
    • Korean Journal of Food Science and Technology
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    • v.36 no.2
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    • pp.349-354
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    • 2004
  • Predictive growth model of Vibrio parahaemolyticus in modified surimi-based imitation crab broth was investigated. Growth curves of V. parahaemolyticus were obtained by measuring cell concentration in culture broth under different conditions ($Initial\;cell\;level,\;1{\times}10^{2},\;1{\times}10^{3},\;and\;1{\times}10^{4}\;colony\;forming\;unit\;(CFU)/mL$; temperature, 15, 25 37, and $40^{\circ}C$; pH 6, 7, and 8) and applying them to Gompertz model. Microbial growth indicators, maximum specific growth rate (k), lag time (LT), and generation time (GT), were calculated from Gompertz model. Maximum specific growth rate (k) of V. parahaemolyticus increased with increasing temperature, reaching maximum rate at $37^{\circ}C$. LT and GT were also the shortest at $37^{\circ}C$. pH and initial cell number did not influence k, LT, and GT values significantly (p>0.05). Polynomial model, $k=a{\cdot}\exp(-0.5{\cdot}((T-T_{max}/b)^{2}+((pH-pH_{max)/c^{2}))$, and square root model, ${\sqrt{k}\;0.06(T-9.55)[1-\exp(0.07(T-49.98))]$, were developed to express combination effects of temperature and pH under each initial cell number using Gauss-Newton Algorism of Sigma plot 7.0 (SPSS Inc.). Relative coefficients between experimental k and k Predicted by polynomial model were 0.966, 0.979, and 0.965, respectively, at initial cell numbers of $1{\times}10^{2},\;1{\times}10^{3},\;and\;1{\times}10^{4}CFU/mL$, while that between experimental k and k Predicted by square root model was 0.977. Results revealed growth of V. parahaemolyticus was mainly affected by temperature, and square root model showing effect of temperature was more credible than polynomial model for prediction of V. parahaemolyticus growth.

Approaches for Developing a Forest Carbon and Nitrogen Model Through Analysis of Domestic and Overseas Models (국내외 모델 분석을 통한 산림 탄소 및 질소 결합 모델 개발방안 연구)

  • Kim, Hyungsub;Lee, Jongyeol;Han, Seung Hyun;Kim, Seongjun;Son, Yowhan
    • Journal of Korean Society of Forest Science
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    • v.107 no.2
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    • pp.140-150
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    • 2018
  • For the estimation of greenhouse gas dynamics in forests, it is useful to use a model which simulates both carbon (C) and nitrogen (N) cycle simultaneously. A forest C model, called FBDC, was developed and validated in Korea. However, studies on development of forest N model are insufficient. This study aimed to suggest a development process of a forest C and N model. We analyzed the general features, structures, ecological processes, input data, output data, and methods of integrating C and N cycles of the VISIT, Biome-BGC, Forest-DNDC, and O-CN. The structure and features of the FBDC were also analyzed. The VISIT was developed by integrating forest C model with a N cycle module, and the new model also could be designed by combining the FBDC with a N cycle module. The VISIT and Forest-DNDC could estimate soil $N_2O$ emissions, and the integrated model should include the processes shared by these models. Especially, the overseas models linked C and N cycles based on N absorption, C absorption, and decomposition of dead organic matter. Therefore, the integration of the FBDC with N cycle module should apply this linkage of structures between C and N cycles. Climate, soil texture, and species distribution data, which are essential for the model development, were available in Korea. However, parameter data associated with N cycle and validation data for soil $N_2O$ emissions need to be obtained by field studies.

Growth and Fresh Bulb Weight Model in Harvest Time of Southern Type Garlic Var. 'Namdo' based on Temperature (온도에 따른 난지형 마늘 '남도'의 생육과 수확기 구생체중 모델 개발)

  • Wi, Seung Hwan;Moon, Kyung Hwan;Song, Eun Young;Son, In Chang;Oh, Soon Ja;Cho, Young Yeol
    • Journal of Bio-Environment Control
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    • v.26 no.1
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    • pp.13-18
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    • 2017
  • This study was conducted to investigate optimal temperature of garlic and develop bulb weight model in harvest time. Day and night temperature in chambers was set to $11/7^{\circ}C$, $14/10^{\circ}C$, $17/12^{\circ}C$, $20/15^{\circ}C$, $23/18^{\circ}C$, $28/23^{\circ}C$(16/8h). Bulb fresh and dry weight was heaviest on $20/15^{\circ}C$. In $11/7^{\circ}C$ and $14/10^{\circ}C$, leaf number and total leaf area increased slowly. But in the harvest, leaf number and total leaf area were not significant, except $28/23^{\circ}C$. Models were developed with fresh bulb weight. As a result of analyzing the model, $18{\sim}20^{\circ}C$ certified optimal mean temperature. And the growing degree day base temperature estimated $7.1^{\circ}C$, upper temperature threshold estimated $31.7^{\circ}C$. To verify the model, mean temperature on temperature gradient tunnel applied to the growth rate model. Lineal function model, quadric model, and logistic distribution model showed 79.0~95.0%, 77.2~92.3% and 85.0~95.8% accuracy, respectively. Logistic distribution model has the highest accuracy and good for explaining moderate temperature, growing degree day base temperature and upper temperature threshold.

A Convergent Investigation on the Thermal Analysis due to Heat Generation of Laptop (노트북 열발생에 따른 열해석에 관한 융합연구)

  • Choi, Kye-Kwang;Cho, Jae-Ung
    • Journal of the Korea Convergence Society
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    • v.11 no.11
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    • pp.189-194
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    • 2020
  • In this study, the durability on heat was considered through the thermal stress analyses on models A, B, and C of laptops. Model A is an integral part, indicating that the heated keyboard showed the highest temperature and the monitor part far from the heated one showed the coldest. In models B and C, only the heated keyboard parts are modeled, so it can be seen that they get hot overall. In the case of model A, the thickness of the laptop keyboard was thicker, but there were the most deformations, while model C had the thinnest thickness with the smallest stress and deformation. Model B had the highest stress but relatively little deformation. It is considered that the result of thermal analysis in this study can be used to make the latest efficient design of durable laptop. The durability of laptop against the heat can be evaluated by applying this study result to the laptop. And it is seen that the result can be the design of laptop with strength and the aesthetic convergence.

Modeling & Analysis of the System Bus on the SoC Platform (SoC 플랫폼에서 시스템 버스의 모델링 및 해석)

  • Cho Young-shin;Lee Je-hoon;Cho Kyoung-rok
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.12
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    • pp.35-44
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    • 2005
  • SoC(systnn-on-a-chip) requires high bandwidth system bus for performing multiple functions. Performance of the system is affected by bandwidth of the system bus. In this paper, for efficient management of the bus resource on a SoC platform, we present a latency model of the shared bus organized by multiple layers. Using the latency model, we can analyze latencies of the shared bus on a SoC. Moreover we evaluate a throughput of the bus and compare with needed throughput of the SoC platform including IPs such as MPEG or USB 2.0. And we can use the results as a criteria to find out an optimal bus architecture for the specific SoC design. For verifying accuracy of the proposed model, we compared the latencies with the simulation result from MaxSim tools. As the result of simulation, the accuracy of the IS model for a single layer and multiple layer are over $96\%\;and\;85\%$ respectively.