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Effects of Entrepreneur Characteristics on Self-efficacy and Business Performance : Focused on Moderating Effects of Entrepreneurship Education and Experience in Business before Starting a Business (창업자 특성이 자기효능감과 창업성과에 미치는 영향 : 창업 전 실무경험과 창업교육의 조절효과를 중심으로)

  • Lee, Chun-Hee;Chun, Dal-Young
    • Journal of Digital Convergence
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    • v.18 no.2
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    • pp.223-233
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    • 2020
  • In academia, lots of startup-related research are conducted to improve startup performance. Most of them are concerned with entrepreneur characteristics, capabilities, and entrepreneurship. In particular, self-efficacy of enterpreneur is emphasized to improve startup performance in addition to entrepreneurial capabilities. Thus, the main research objectives of this study are as follows. First, the impact of entrepreneur characteristics is investigated on self-efficacy and startup performance. Second, the moderating effects of business experience prior to startup and entrepreneurship education are analyzed between entrepreneur characteristics and self-efficacy. Finally, managerial strategies are suggested to maximize startup performance via self-efficacy. 274 samples were collected from independent startups. The proposed research model and 17 hypotheses were verified with structural equation modeling techenique. The empirical findings are as follows. First, psychological characteristics such as achievement desire and risk tolerance positively influenced on self-efficacy. Second, business experience prior to startup showed significant moderating effects on self-efficacy with technological and marketing capabilities. and entrepreneurship education. Third, entrepreneurship education showed significant moderating effects on self-efficacy with achievement desire, risk tolerance, technological and marketing capabilities.

Estimation of Carbon Sequestration and Its Profit Analysis with Different Application Rates of Biochar during Corn Cultivation Periods (옥수수 재배기간 동안 바이오차 시용 수준에 따른 탄소 격리량 산정 및 이익 분석)

  • Shin, JoungDu;Choi, Yong-Su;Lee, SunIl
    • Journal of the Korea Organic Resources Recycling Association
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    • v.24 no.3
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    • pp.83-90
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    • 2016
  • Despite the ability of biochar to enhance soil fertility and to mitigate greenhouse gas, its carbon sequestration and profit analysis with arable land application have been a few evaluated. This study was conducted to estimate carbon sequestration and to evaluate profit of greenhouse gas mitigation during corn cultivation periods. For the experiment, the biochar application rates were consisted of pig compost(non application), 2,600(0.2%), 13,000(1%), and 26,000(2%) kg/ha based on pig compost application. For predicting soil carbon sequestration of biochar application, it was appeared to be linear model of Y = 0.5523X - 742.57 ($r^2=0.939^{**}$). Based on this equation, soil carbon sequestration by 0.2, 1 and 2% biochar application was estimated to be 1,235, 3,978, and 14,794 kg/ha, and their mitigations of $CO_2$-eq. emissions were estimated to be 4.5, 14.6, and 54.2 ton/ha, respectively. Their profits were estimated at $14.6 for lowest and $452 for highest. In Korea Climate Exchange, it was estimated that the market price of $CO_2$ in corn cultivation periods with 0.2, 1 and 2% biochar application was $35.6, $115.3 and $428.2 per hectare, respectively. For the plant growth response, it was observed that plant height and fresh ear yield were not significantly different among the treatments. Therefore, these experimental results might be fundamental data for assuming a carbon trading mechanism exists for biochar soil application in agricultural practices.

Evaluation of Interlayer Shear Properties and Bonding Strengths of a Stress-Absorbing Membrane Interlayer and Development of a Predictive Model for Fracture Energy (덧씌우기 응력흡수층에 대한 전단, 부착강도 평가 및 파괴에너지 예측모델 개발)

  • Kim, Dowan;Mun, Sungho;Kwon, Ohsun;Moon, Kihoon
    • International Journal of Highway Engineering
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    • v.20 no.1
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    • pp.87-95
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    • 2018
  • PURPOSES : A geo-grid pavement, e.g., a stress-absorbing membrane interlayer (SAMI), can be applied to an asphalt-overlay method on the existing surface-pavement layer for pavement maintenance related to reflection cracking. Reflection cracking can occur when a crack in the existing surface layer influences the overlay pavement. It can reduce the pavement life cycle and adversely affect traffic safety. Moreover, a failed overlay can reduce the economic value. In this regard, the objective of this study is to evaluate the bonding properties between the rigid pavement and a SAMI by using the direct shear test and the pull-off test. The predicted fractural energy functions with the shear stress were determined from a numerical analysis of the moving average method and the polynomial regression method. METHODS : In this research, the shear and pull-off tests were performed to evaluate the properties of mixtures constructed using no interlayer, a tack-coat, and SAMI with fabric and without fabric. The lower mixture parts (describing the existing pavement) were mixed using the 25-40-8 joint cement-concrete standard. The overlay layer was constructed especially using polymer-modified stone mastic asphalt (SMA) pavement. It was composed of an SMA aggregate gradation and applied as the modified agent. The sixth polynomial regression equation and the general moving average method were utilized to estimate the interlayer shear strength. These numerical analysis methods were also used to determine the predictive models for estimating the fracture energy. RESULTS : From the direct shear test and the pull-off test results, the mixture bonded using the tack-coat (applied as the interlayer between the overlay layer and the jointed cement concrete) had the strongest shear resistance and bonding strength. In contrast, the SAMI pavement without fiber has a strong need for fractural energy at failure. CONCLUSIONS : The effects of site-reflection cracking can be determined using the same tests on cored specimens. Further, an empirical-mechanical finite-element method (FEM) must be done to understand the appropriate SAMI application. In this regard, the FEM application analy pavement-design analysis using thesis and bonding property tests using cored specimens from public roads will be conducted in further research.

A Study on the Relationship between Justice Perception of Franchise and Trust, Switching Barriers of the Franchisee in the Barriers and Beauty Parlors Business (이.미용업에서의 프랜차이즈 공정성 지각이 신뢰와 전환장벽에 미치는 영향)

  • Kim, Kyeong Ran;Ryu, Hwang Gun;Oh, Chang Seok
    • The Korean Journal of Health Service Management
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    • v.1 no.1
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    • pp.75-89
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    • 2007
  • The start point of a franchise system such as Lotteria was in 1979. Since 1990, the franchise systems in Korea have rapidly spread over all industry types. As 'Franchise Law' was enforced in 2002, the expansion of a franchise picked up its' speed. The barbers and beauty parlors business has the same expansion trend. However, there was no study about the franchise systems in the barbers and beauty parlors business. The purpose of this study was to find the goodness of fit of the structured equation model proposed and identify the significances of relationships in the variables of justice perceptions, trust, satisfactions, business performances, switching barriers, switching cost etc. This study tries to find a solution for a good development between franchisor and franchisee in the barbers and beauty parlors business in Korea. The theoretical considerations about justice of this study is limited in reciprocal relation justice and procedure justice. And it did make simplify for trust, satisfaction, business performance, switching barrier. And switching barrier did measure as dimension of switching coot. From October 26, 2005 to October 29, this study collected 250 survey questionnaires from the franchisees located in Seoul, Busan, Daegu, Ulsan, and Keoyng-Nam. In analyses of using SPSS Windows 11.0 and LISREL 8.14, this study used 208 cases because 48 cases did not response appropriately. Tn conclusions. reciprocal justice perception and procedure justice jointly determined trust. Secondly, reciprocal justice perception significantly determined satisfaction. Procedure justice perception negatively determined satisfaction, but this relationship was not significant. Thirdly, reciprocal justice perception positively influenced business performance, and procedure justice negatively influenced business performance, but the last relationship was not significant Fourthly, trust positively significantly influenced satisfaction and business performance. Fifthly, satisfaction positively influenced business performance and true determined switching barrier positively. This study shows following: firstly, a composition concept did make structural relationship and secondly, a reciprocal relation justice of a franchisor did appear as an important variable and it gives positive influence to trust, satisfactions, business performance, switching barriers of the franchisees.

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Growth and Electrical Properties of ZnAl2Se4 Single Crystal Thin Film by Hot Wall Epitaxy (Hot Wall Epitaxy(HWE)법에 의한 ZnAl2Se4 단결정 박막 성장과 가전자대 갈라짐에 대한 광전류 연구)

  • Park, Hyangsook;Bang, Jinju;Lee, Kijung;Kang, Jongwuk;Hong, Kwangjoon
    • Korean Journal of Materials Research
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    • v.23 no.12
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    • pp.714-721
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    • 2013
  • A stoichiometric mixture of evaporating materials for $ZnAl_2Se_4$ single-crystal thin films was prepared in a horizontal electric furnace. These $ZnAl_2Se_4$ polycrystals had a defect chalcopyrite structure, and its lattice constants were $a_0=5.5563{\AA}$ and $c_0=10.8897{\AA}$.To obtain a single-crystal thin film, mixed $ZnAl_2Se_4$ crystal was deposited on the thoroughly etched semi-insulating GaAs(100) substrate by a hot wall epitaxy (HWE) system. The source and the substrate temperatures were $620^{\circ}C$ and $400^{\circ}C$, respectively. The crystalline structure of the single-crystal thin film was investigated by using a double crystal X-ray rocking curve and X-ray diffraction ${\omega}-2{\theta}$ scans. The carrier density and mobility of the $ZnAl_2Se_4$ single-crystal thin film were $8.23{\times}10^{16}cm^{-3}$ and $287m^2/vs$ at 293 K, respectively. To identify the band gap energy, the optical absorption spectra of the $ZnAl_2Se_4$ single-crystal thin film was investigated in the temperature region of 10-293 K. The temperature dependence of the direct optical energy gap is well presented by Varshni's relation: $E_g(T)=E_g(0)-({\alpha}T^2/T+{\beta})$. The constants of Varshni's equation had the values of $E_g(0)=3.5269eV$, ${\alpha}=2.03{\times}10^{-3}eV/K$ and ${\beta}=501.9K$ for the $ZnAl_2Se_4$ single-crystal thin film. The crystal field and the spin-orbit splitting energies for the valence band of the $ZnAl_2Se_4$ were estimated to be 109.5 meV and 124.6 meV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $ZnAl_2Se_4/GaAs$ epilayer. The three photocurrent peaks observed at 10 K are ascribed to the $A_1$-, $B_1$-exciton for n = 1 and $C_{21}$-exciton peaks for n = 21.

Biological Dosimetry of In Vitro Irradiation with Radionuclides : Comparison of Whole Blood, Lymphocyte and Buffy Coat Culture (전혈, 림프구와 백혈구 연층 각각의 방사성 동위원소 체외 조사 후 배양을 이용한 생물학적 선량측정)

  • Kim, Jong-Ho;Lee, Dong-Soo;Choi, Chang-Woon;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon;Kim, Chong-Soon;Kim, Hee-Geun;Kang, Duck-Won;Song, Myung-Jae
    • The Korean Journal of Nuclear Medicine
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    • v.29 no.1
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    • pp.125-132
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    • 1995
  • The purpose of this study was to establish mononuclear cell cultures such as lymphocytes or buffy coat for the biological dosimetry of in vitro Irradiation of the radionuclide Tc-99m in order to exclude the effect of residual doses seen in the cultures of whole blood. Biological do simetry of Tc-99m on cultured mononuclear cells at doses ranging from 0.05 to 6.00 Gy, by scoring unstable chromosomal aberrations(Ydr) observed in cultured lymphocytes, were performed using peripheral venous blood of healthy normal person. The results showed that; (1) In vitro irradiation of radioisotope in separated lymphocyte or buffy coat showed trace amount of residual doses of isotope after washing. Residual doses of isotopes are increased in proportion to exposed time and irradiated dose without difference between I-131 and Tc-99m. (2) We obtained these linear-quadratic dose response equations in lymphocyte and buffy coat culture after in vitro irradiation of Tc-99m, respectively (Ydr = 0.001949 $D^2$ +0.006279D + 0.000185; Ydr= 0.002531 $D^2$-0.003274 D+0.003488). In conclusion, the linear quadratic dose-response equation from in vitro irradiation of Tc-99m with lymphocyte and buffy coat culture was thought to be useful for assessing Tc-99m induced biological effects. And mono-nuclear cell cultures seem to be the most appropriate experimental model for the assessment of biological dosimetry of internal irradiation of radionuclides.

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Determination of Optimal Unit Hydrographs and Infultration Rate Functions from Single Rainfall-Runoff Event (단순 강우-유출 사상으로부터 최적단위도와 침투율의 결정)

  • An, Tae-Jin;Ryu, Hui-Jeong;Jeong, Gwang-Geun;Sim, Myeong-Pil
    • Journal of Korea Water Resources Association
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    • v.33 no.3
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    • pp.365-374
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    • 2000
  • This paper is to present the determination of the optimal Joss rate parameters and urnt bydrographs from the observed single rainfall-runoff event using optimization models coupled with a stochastic technique for the global solution. Two kinds of the linear program models are formulated to derive the optimal unit hydrographs and loss rate parameters for gaged basins; one mimmizes the summation of the absolute residual between predlCted and observed runoff ordinates and the other, the maximum absolute residuaL Multistart algorithm which is one or stochastic techniques for the global optimum is adopted to perturb the parameters of the loss rate equations. Multistart efficiently searches the feasIble region to identify the global optimlUll for loss rate parameters, which yields the optimal loss rate parameters and unit hydrograph for Kostiakov's, Plulip's, and Horton's equation. The unique unit hydrograph ordinates for a gIven rainfall-runoff event iS exclusrvely obtained WIth $\Phi$ index, but unit hydrograph ordinates depend upon the parameters [or each loss rate equations. The parameters of Green-Ampt's are determined through a trial and error method. In this paper the single rainfall-nmoff event observed from a watershed is considered to test the proposed method. The optimal unit hydrograph herein found has smaller deviations than the ones reported previously by other researchers.

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The Adsorption and Desorption of $NH_3$ on Rutile $TiO_2(110)-1{\times}1$ Surfaces

  • Kim, Bo-Seong;Li, Zhenjun;Kay, Bruce D.;Dohnalek, Zdenek;Kim, Yu-Gwon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.265-265
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    • 2012
  • The adsorption of molecular $NH_3$ on rutile $TiO_2(110)-1{\times}1$ surfaces was investigated using a temperature-programmed desorption (TPD) technique combined with a molecular beam apparatus. A quantitative investigation into the TPD spectra of $NH_3$ was made for $NH_3$ adsorbed on two kinds of rutile $TiO_2(110)-1{\times}1$ surfaces with the oxygen vacancy ($V_O$) concentration of ~0% (p-$TiO_2(110)$) and ~5% (r-$TiO_2(110)$), respectively. On both surfaces, non-dissociative adsorption of $NH_3$ was inferred from a quantitative analysis on the amount of adsorbed $NH_3$ and those desorbed. With increasing coverage, the monolayer desorption feature shifted from 400 K toward lower temperatures until it saturates at 160 K, suggesting a repulsive nature in the interaction between $NH_3$ molecules. At the very low coverage regime, the desorption features were found to extend up to 430 K and 400 K on p-$TiO_2(110)$ and p-TiO(110), respectively. As a result, the saturation coverage of monolayer of $NH_3$ was higher on the p-$TiO_2(110)$ surface than on the p-TiO(110) by about 10%. The desorption energy ($E_d$) of $NH_3$ obtained by inversion of the Polanyi-Wigner equation indicated that the difference between the $E_d$'s of $NH_3$ (that is, $E_d(on\;p-TiO_2(110)$) - $E_d$(on p-TiO(110)) was 14 kJ/mol at ${\theta}(NH_3)=0$ and decreased to 0 as the coverage approached to a monolayer. The observed adsorption behavior of $NH_3$ was interpreted using an interaction model between $NH_3$ and surface defects on $TiO_2$ such as VO's and $Ti^{3+}$ interstitials.

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Investigation of the processing characteristics of soybean sprouts after germination of HaePum during a long storage period with different temperature and humidity (장기 저장 중 저장 온도와 습도에 따른 해품 콩의 콩나물 가공적성 연구)

  • Lee, Yun Ju;Yoon, Won Byong
    • Journal of Applied Biological Chemistry
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    • v.63 no.1
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    • pp.1-8
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    • 2020
  • This study investigated the processing characteristics of soybean (HaePum) sprouts based on temperature (5, 15 and room temperature), period (0, 6 and 12 mon) and relative humidity (20, 40, 60, and 80%) during storage. The initial germination rate of soybean sprouts was 76.02±6.32%, which significantly reduced to 57.18±8.51%, and 0% as the storage temperature of soybean increased for a period of 12 mon. The germination rate of soybean sprouts with 30 ℃ and 80% RH decreased after 4 mon of storage to 4.94%. The yellowness of cotyledon of soybean sprouts was not significantly changed during the 12 mon period of storage at 5 ℃, whereas, soybean sprouts stored at 15 ℃ and room temperature demonstrated decreased yellowness. However, the stress of cotyledon decreased with an increase in both storage temperature and time, and the hardness of hypocotyl decreased with an increase of storage time. The stress of cotyledon affected by high temperature (30 ℃) and humidity (80%) during 4 mon was reduced to 44.39±9.38 g/㎟. The asparagine content of soybean sprouts showed a similar result with the germination rate due to the amount of hypocotyl. Therefore, lower temperatures and shorter storage times are suitable for soybean sprout processing. The first order kinetic model and Arrhenius equation (activation energy =29.56 kJ/mol) were able to predict the yield of sprout at various storage temperatures and periods.

The Causality among Residents' Loyalty to an Environmental Festival and Its Influential Factors: With Special Reference to Hampyung Butterfly Festival (지역주민의 환경축제 충성도와 그 영향요인 간의 인과관계 - 함평나비축제를 중심으로 -)

  • Lee, Kyeong-Jin;Song, Myung-Gyu
    • Journal of Environmental Impact Assessment
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    • v.23 no.5
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    • pp.337-352
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    • 2014
  • The main purposes of this study are to find the causality among residents' loyalty to an environmental festival and its influential factors and, based upon the findings, to explore environmental festivals' developmental vision with special reference to Hampyung Butterfly Festival. Under these aims, this study applies structural equation modeling(SEM). The structural model for SEM analysis is composed of four independent variables which consist of residents' attachment(RA) to their region where its own environmental festival is provided, residents' participational intention(RP) to the festival, the economic effects(EE) of the festival, and the communication(CM) between the residents and the festival providers, one intermediate variable, residents' satisfaction(RS) from the festival, and one final dependent variable, residents' loyalty(RL) to the festival. The causality among these variables is hypothesized as follows; Among the independent variables, RP, EE, and CM have effects only on RS and RA has an effect on both RS and RL. And RS has an effect on RL. The facts found from the SEM are summed up as follows; First, (1) RP and CM turn out to have statistically significant effects on RS, (2) RA is confirmed to have a statistically very significant effect on both RS and RL, and (3) RS is also proved to show a statistically very significant effect on RL. Second, the total effects on RL of independent variables are stronger in the order of RA, CM, and RP. Third, EE seems to have no effect on RS, consequently no effect on RL, either. The reason why EE has no effect looks like to be due to environmental festivals' peculiar features. These findings offer the following suggestions for the future of environmental festivals in the part of festival providers. Firstly, to be successful in the festival, they have to provoke RL above all. Second, to do so, they need to encourage RA, CM, and RP in the mentioned order in the long run. Third, but for a short period, they had better concentrate upon promoting RS.