• Title/Summary/Keyword: model studies

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A Study on Dose-Response Models for Foodborne Disease Pathogens (주요 식중독 원인 미생물들에 대한 용량-반응 모델 연구)

  • Park, Myoung Su;Cho, June Ill;Lee, Soon Ho;Bahk, Gyung Jin
    • Journal of Food Hygiene and Safety
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    • v.29 no.4
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    • pp.299-304
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    • 2014
  • The dose-response models are important for the quantitative microbiological risk assessment (QMRA) because they would enable prediction of infection risk to humans from foodborne pathogens. In this study, we performed a comprehensive literature review and meta-analysis to better quantify this association. The meta-analysis applied a final selection of 193 published papers for total 43 species foodborne disease pathogens (bacteria 26, virus 9, and parasite 8 species) which were identified and classified based on the dose-response models related to QMRA studies from PubMed, ScienceDirect database and internet websites during 1980-2012. The main search keywords used the combination "food", "foodborne disease pathogen", "dose-response model", and "quantitative microbiological risk assessment". The appropriate dose-response models for Campylobacter jejuni, pathogenic E. coli O157:H7 (EHEC / EPEC / ETEC), Listeria monocytogenes, Salmonella spp., Shigella spp., Staphylococcus aureus, Vibrio parahaemolyticus, Vibrio cholera, Rota virus, and Cryptosporidium pavum were beta-poisson (${\alpha}=0.15$, ${\beta}=7.59$, fi = 0.72), beta-poisson (${\alpha}=0.49$, ${\beta}=1.81{\times}10^5$, fi = 0.67) / beta-poisson (${\alpha}=0.22$, ${\beta}=8.70{\times}10^3$, fi = 0.40) / beta-poisson (${\alpha}=0.18$, ${\beta}=8.60{\times}10^7$, fi = 0.60), exponential (r=$1.18{\times}10^{-10}$, fi = 0.14), beta-poisson (${\alpha}=0.11$, ${\beta}=6,097$, fi = 0.09), beta-poisson (${\alpha}=0.21$, ${\beta}=1,120$, fi = 0.15), exponential ($r=7.64{\times}10^{-8}$, fi = 1.00), betapoisson (${\alpha}=0.17$, ${\beta}=1.18{\times}10^5$, fi = 1.00), beta-poisson (${\alpha}=0.25$, ${\beta}=16.2$, fi = 0.57), exponential ($r=1.73{\times}10{-2}$, fi = 1.00), and exponential ($r=1.73{\times}10^{-2}$, fi = 0.17), respectively. Therefore, these results provide the preliminary data necessary for the development of foodborne pathogens QMRA.

Buyers' Trust in a Brand and Brand Loyalty in the business-to-business (산업재 시장에서 브랜드 신뢰와 브랜드 충성도에 관한 연구)

  • Han, Sang-Rin;Sung, Hyung-Suk
    • Proceedings of the Korean DIstribution Association Conference
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    • 2005.11a
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    • pp.29-51
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    • 2005
  • Brands are important in the consumer market. They are the interface between consumers and the company, consumers may develop loyalty to brands. also, The late development of industrial marketing explains the near absence of research on Brand Equity in business to business. With recent change, industrial companies have shifted from a production focus to a customer focus. industrial brand is fast developing. The basic purpose of this study is to investigate industrial brand trust and loyalty affecting the Result of business relationship between industrial buyers and suppliers. Factors hypothesized to influence trust in a brand include a number of brand characteristics, company characteristics and consumer-brand characteristics. This research presented a comprehensive constructive model consisting of components of industrial brand trust and loyalty, and then propose the research model base on prior researches and studies about relationships among components of industrial brand loyalty. Data were gathered from respondents who work in industrial buying center. For this study, Data were analyzed by SPSS 10.0 and AMOS 4.0. The results of this research analysis were as fallow. Industrial brand trust and loyalty were positively related with a number of industrial brand characteristics, supplier characteristics and buyer-brand characteristics. relationship commitment. This research newly proposed the concept of 'industrial brand trust and loyalty affecting the Result of business relationship between industrial buyers and suppliers'

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Statics corrections for shallow seismic refraction data (천부 굴절법 탄성파 탐사 자료의 정보정)

  • Palmer Derecke;Nikrouz Ramin;Spyrou Andreur
    • Geophysics and Geophysical Exploration
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    • v.8 no.1
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    • pp.7-17
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    • 2005
  • The determination of seismic velocities in refractors for near-surface seismic refraction investigations is an ill-posed problem. Small variations in the computed time parameters can result in quite large lateral variations in the derived velocities, which are often artefacts of the inversion algorithms. Such artefacts are usually not recognized or corrected with forward modelling. Therefore, if detailed refractor models are sought with model based inversion, then detailed starting models are required. The usual source of artefacts in seismic velocities is irregular refractors. Under most circumstances, the variable migration of the generalized reciprocal method (GRM) is able to accommodate irregular interfaces and generate detailed starting models of the refractor. However, where the very-near-surface environment of the Earth is also irregular, the efficacy of the GRM is reduced, and weathering corrections can be necessary. Standard methods for correcting for surface irregularities are usually not practical where the very-near-surface irregularities are of limited lateral extent. In such circumstances, the GRM smoothing statics method (SSM) is a simple and robust approach, which can facilitate more-accurate estimates of refractor velocities. The GRM SSM generates a smoothing 'statics' correction by subtracting an average of the time-depths computed with a range of XY values from the time-depths computed with a zero XY value (where the XY value is the separation between the receivers used to compute the time-depth). The time-depths to the deeper target refractors do not vary greatly with varying XY values, and therefore an average is much the same as the optimum value. However, the time-depths for the very-near-surface irregularities migrate laterally with increasing XY values and they are substantially reduced with the averaging process. As a result, the time-depth profile averaged over a range of XY values is effectively corrected for the near-surface irregularities. In addition, the time-depths computed with a Bero XY value are the sum of both the near-surface effects and the time-depths to the target refractor. Therefore, their subtraction generates an approximate 'statics' correction, which in turn, is subtracted from the traveltimes The GRM SSM is essentially a smoothing procedure, rather than a deterministic weathering correction approach, and it is most effective with near-surface irregularities of quite limited lateral extent. Model and case studies demonstrate that the GRM SSM substantially improves the reliability in determining detailed seismic velocities in irregular refractors.

Estimation Model for Simplification and Validation of Soil Water Characteristics Curve on Volcanic Ash Soil in Subtropical Area in Korea (난지권 화산회토양의 토색별 토양수분 특성곡선 및 단일화 추정모형)

  • Hur, Seung-Oh;Moon, Kyung-Hwan;Jung, Kang-Ho;Ha, Sang-Keun;Song, Kwan-Cheol;Lim, Han-Cheol;Kim, Geong-Gyu
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.6
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    • pp.329-333
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    • 2006
  • Most of volcanic ash soils in South Korea are distributed in Jeju province which is an island placed on southern part of Korea and has steep slope mountain area. There are many soils containing high contents of organic matter (OM) derived from volcanic ash in Jejudo, also. Therefore, irrigation and drainage in volcanic ash soil different with general soil which has low OM content have to be applied with another management way, but studies searching appropriate methods for them are set on insufficient situation because the area of volcanic ash soil in South Korea is only 1.3% (130,000ha). This study was conducted for analysis of soil water content and irrigation quantity appropriate for crops cultivated in volcanic ash soil with high OM content. Although soils with different soil color have the same soil texture, soil water characteristics curve by soil color showed the difference of water retention capability by OM content. But, this characteristics classified with soil color could be unified by scaling technique with similitude analysis method which get dimensionless water content using a present water content, a residual water content and saturated water content (or water content at 10kPa). A relation of gravimetric soil water content (GSWC) and dimensionless water content by the results showed a form of power function. The dimensionless water content (DWC) express a relative saturation degree of present water content. This was also expressed by van Genuchten model which describe the relation between relative saturation degrees and matric potentials. These results on soil water characteristics curve (SWCC) of volcanic ash soil will be the basic of irrigation plan in area having high organic contents into soil.

Effect of Lead Content on Atomic Structures of Pb-bearing Sodium Silicate Glasses: A View from 29Si NMR Spectroscopy (납 함량에 따른 비정질 Pb-Na 규산염의 원자 구조에 대한 고상 핵자기 공명 분광분석 연구)

  • Lee, Seoyoung;Lee, Sung Keun
    • Korean Journal of Mineralogy and Petrology
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    • v.34 no.3
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    • pp.157-167
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    • 2021
  • Lead (Pb) is one of the key trace elements, exhibiting a peculiar partitioning behavior into silicate melts in contact with minerals. Partitioning behaviors of Pb between silicate mineral and melt have been known to depend on melt composition and thus, the atomic structures of corresponding silicate liquids. Despite the importance, detailed structural studies of Pb-bearing silicate melts are still lacking due to experimental difficulties. Here, we explored the effect of lead content on the atomic structures, particularly the evolution of silicate networks in Pb-bearing sodium metasilicate ([(PbO)x(Na2O)1-x]·SiO2) glasses as a model system for trace metal bearing natural silicate melts, using 29Si solid-state nuclear magnetic resonance (NMR) spectroscopy. As the PbO content increases, the 29Si peak widths increase, and the maximum peak positions shift from -76.2, -77.8, -80.3, -81.5, -84.6, to -87.7 ppm with increasing PbO contents of 0, 0.25, 0.5, 0.67, 0.86, and 1, respectively. The 29Si MAS NMR spectra for the glasses were simulated with Gaussian functions for Qn species (SiO4 tetrahedra with n BOs) for providing quantitative resolution. The simulation results reveal the evolution of each Qn species with varying PbO content. Na-endmember Na2SiO3 glass consists of predominant Q2 species together with equal proportions of Q1 and Q3. As Pb replaces Na, the fraction of Q2 species tends to decrease, while those for Q1 and Q3 species increase indicating an increase in disproportionation among Qn species. Simulation results on the 29Si NMR spectrum showed increases in structural disorder and chemical disorder as evidenced by an increase in disproportionation factor with an increase in average cation field strengths of the network modifying cations. Changes in the topological and configurational disorder of the model silicate melt by Pb imply an intrinsic origin of macroscopic properties such as element partitioning behavior.

A Study on the Effect of SMEs' Organizational Culture and Self-Efficacy on Job Crafting and Job Satisfaction (소기업의 조직문화와 자기효능감이 잡 크래프팅과 직무만족도에 미치는 영향에 관한 연구)

  • Bae, Keun Soo;Heo, Ghul Moo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.5
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    • pp.109-124
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    • 2021
  • This study tried to verify the causal relationship that SMEs' organizational culture and self-efficacy would affect job crafting and job satisfaction. Unlike previous domestic studies that have been studied for organizational culture at the organizational level and self-efficacy at the individual level, this study tried to verify the interaction between job crafting and job satisfaction using different mechanisms as antecedent factors. In order to verify the research model of this study, questionnaires of 144 small and medium-sized enterprises (SMEs) workers located in Seoul and metropolitan areas were analyzed. Factor analysis and correlation analysis were performed to verify the reliability and validity of the research model on the relationship between variables, and empirical analysis was performed using regression analysis and mediation effect analysis to verify the hypothesis. The results of the study were first, that organizational culture and self-efficacy had a positive (+) effect on job crafting. On the other hand, relationship-oriented culture and hierarchical-oriented culture, which are sub-factors of organizational culture, were found to be insignificant. Second, organizational culture and self-efficacy were found to have a positive (+) effect on job satisfaction. On the other hand, it was found that market-oriented culture and hierarchical-oriented culture, which are sub-factors of organizational culture, were not significant. Third, job crafting was found to have a positive (+) effect on job satisfaction. On the other hand, it was found that the sub-factors of job crafting, disruptive job demands and social job resources, were not significant. This means that organizational culture partially affects job crafting and job satisfaction of SMEs, and job crafting also partially affects job satisfaction. The implications of this study are first, suggesting the meaning of SME organizational culture for stable and efficient human resource management for SMEs suffering from low productivity and high turnover rate. Second, it was meaningful to understand the possibility of introducing job crafting as an effective job management plan for SMEs. Third, in the current situation where there are few cases of practical introduction of job crafting, research on understanding job crafting for SMEs and improving job satisfaction is thought to be helpful in improving the productivity of SMEs.

Shipping Industry Support Plan based on Research of Factors Affecting on the Freight Rate of Bulk Carriers by Sizes (부정기선 운임변동성 영향 요인 분석에 따른 우리나라 해운정책 지원 방안)

  • Cheon, Min-Soo;Mun, Ae-ri;Kim, Seog-Soo
    • Journal of Korea Port Economic Association
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    • v.36 no.4
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    • pp.17-30
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    • 2020
  • In the shipping industry, it is essential to engage in the preemptive prediction of freight rate volatility through market monitoring. Considering that freight rates have already started to fall, the loss of shipping companies will soon be uncontrollable. Therefore, in this study, factors affecting the freight rates of bulk carriers, which have relatively large freight rate volatility as compared to container freight rates, were quantified and analyzed. In doing so, we intended to contribute to future shipping market monitoring. We performed an analysis using a vector error correction model and estimated the influence of six independent variables on the charter rates of bulk carriers by Handy Size, Supramax, Panamax, and Cape Size. The six independent variables included the bulk carrier fleet volume, iron ore traffic volume, ribo interest rate, bunker oil price, and Euro-Dollar exchange rate. The dependent variables were handy size (32,000 DWT) spot charter rates, Supramax 6 T/C average charter rates, Pana Max (75,000 DWT) spot charter, and Cape Size (170,000 DWT) spot charter. The study examined charter rates by size of bulk carriers, which was different from studies on existing specific types of ships or fares in oil tankers and chemical carriers other than bulk carriers. Findings revealed that influencing factors differed for each ship size. The Libo interest rate had a significant effect on all four ship types, and the iron ore traffic volume had a significant effect on three ship types. The Ribo rate showed a negative (-) relationship with Handy Size, Supramax, Panamax, and Cape Size. Iron ore traffic influenced three types of linearity, except for Panamax. The size of shipping companies differed depending on their characteristics. These findings are expected to contribute to the establishment of a management strategy for shipping companies by analyzing the factors influencing changes in the freight rates of charterers, which have a profound effect on the management performance of shipping companies.

Consumption of Han-sik and its Association with Socioeconomic Status among Filipino Immigrant Women: the Filipino Women's Diet and Health Study (FiLWHEL) (필리핀 결혼이민여성의 한식 섭취실태 및 한식 섭취율에 따른 사회경제학적 요인)

  • Kim, Nayeon;Kang, Minji;Abris, Grace;Provido, Sherlyn Mae P.;Joung, Hyojee;Hong, Sangmo;Yu, Sung Hoon;Lee, Chang Beom;Lee, Jung Eun
    • Korean Journal of Community Nutrition
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    • v.23 no.6
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    • pp.475-487
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    • 2018
  • Objectives: This study examined the consumption of Han-sik and its association with the years of residence in Korea and the socioeconomic status among Filipino immigrant women of the Filipino Women's Diet and Health Study (FiLWHEL). Methods: A total of 474 Filipino women married to Korean men were included in the analysis. Their dietary intake was assessed using a single-day 24-hour recall. The participants provided information on the demographics, socioeconomic, and health-related factors through face-to-face interviews. The generalized linear model and logistic regression model were used to examine the association between the socioeconomic status and consumption of Han-sik. Results: The mean age of the participants was 34.3 years old, and the average duration of residence in Korea was 8.2 years. Among 474 Filipino women, a total of 467 consumed Han-sik, with an average of 6.8 food items per day. The Han-sik foods that the participants consumed most frequently were rice, cabbage kimchi, mixed-grain rice, and fried eggs. The average ratio of Han-sik was 58.57%. The ratio of Han-sik showed no significant associations with the years of residence, years of living together with their husband, education levels, total annual family income, or linguistic competence of Korean. However, the ratio of Han-sik use was associated with cohabitation with parents-in-law; the odds ratio (95% confidence interval) was 2.41 (1.18-4.92, p-trend = 0.002) comparing the fourth quartile with the first quartile of the Han-sik ratio. Conclusions: Filipino immigrant women in the FiLWHEL study consumed a larger number of Han-sik than Philippine foods. In addition, cohabitation with their parents-in-law was associated with the consumption of Han-sik. Further epidemiologic studies will be needed to determine how the diet affects the health and wellbeing of immigrant women in Korea.

Estimation of the Three-dimensional Vegetation Landscape of the Donhwamun Gate Area in Changdeokgung Palace through the Rubber Sheeting Transformation of (<동궐도(東闕圖)>의 러버쉬팅변환을 통한 창덕궁 돈화문 지역의 입체적 식생 경관 추정)

  • Lee, Jae-Yong
    • Korean Journal of Heritage: History & Science
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    • v.51 no.2
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    • pp.138-153
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    • 2018
  • The purpose of this study was to analyze , which was made in the late Joseon Dynasty to specify the vegetation landscape of the Donhwamun Gate area in Changdeokgung Palace. The study results can be summarized as below. First, based on "Jieziyuan Huazhuan(芥子園畵傳)", the introductory book of tree expression delivered from China in the 17th century, allowed the classification criteria of the trees described in the picture to be established and helped identify their types. As a result of the classification, there were 10 species and 50 trees in the Donhwamun Gate area of . Second, it was possible to measure the real size of the trees described in the picture through the elevated drawing scale of . The height of the trees ranged from a minimum of 4.37 m to a maximum of 22.37 m. According to the measurement results, compared to the old trees currently living in Changdeokgung Palace, the trees described in the picture were found to be produced in almost actual size without exaggeration. Thus, the measured height of the trees turned out to be appropriate as baseline data for reproduction of the vegetation landscape. Third, through the Rubber Sheeting Transformation of , it was possible to make a ground plan for the planting of on the current digital topographic map. In particular, as the transformed area of was departmentalized and control points were added, the precision of transformation improved. It was possible to grasp the changed position of planting as well as the change in planting density through a ground plan of planting of . Lastly, it was possible to produce a three-dimensional vegetation landscape model by using the information of the shape of the trees and the ground plan for the planting of . Based on the three-dimensional model, it was easy to examine the characteristics of the three-dimensional view of the current vegetation via the view axis, skyline, and openness to and cover from the adjacent regions at the level of the eyes. This study is differentiated from others in that it verified the realism of and suggested the possibility of ascertaining the original form of the vegetation landscape described in the painting.

Influential Factors on Technology Acceptance of Augmented Reality(AR) (증강현실(Augmented Reality: AR) 기술수용에 영향을 미치는 요인)

  • Chung, Byoung Gyu;Dong, Hak Lim
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.3
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    • pp.153-168
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    • 2019
  • Augmented Reality(AR) has been one of the important technologies of the 4th industrial revolution. Consumer acceptance of new technologies is substantial issue for market expansion, but there have been few empirical studies on factors that affect the acceptance or use intention of AR. In this study, we have explored and analyzed the factors influencing technology acceptance based on the extended unified theory of acceptance and use of technology(UTAUT2) model in the AR business and have discussed it with comparison with existing research based on this analysis. The results of this study suggest that the main variables of the existing UTAUT1 model had significant positive effect on the intention to use, such as performance expectancy, effort expectancy, facilitating conditions and hedonic motivation, habits of UTAUT2. In addition, perceived risk introduced in this study had a negative effect on intention to use. Furthermore, the impact between these two factors have been effort expectancy(${\beta}=.294$)>habits(${\beta}=.268$)>hedonic motivation(${\beta}=.266$)>performance expectancy,(${\beta}=.263$)>facilitating conditions(${\beta}=.233$)>perceived risk(${\beta}=-.094$). The impact of social influence did not have a significant effect on intention to use. The intention to use was analyzed to have a significant positive effect on the actual use and recommendation intention. On the other hand, the hypothesis that the age and gender has played a moderating role between independent variables and the intention of use were investigated. Age was found out to play a role as a moderator between social influence, facilitating conditions, hedonic motivation, habits and intention to use. In the same way, gender has been shown to play a moderating role between facilitating conditions, perceived risk and intention to use. Academic and practical implications are suggested based on the results of this study.