• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.1
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• pp.9-26
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• 1997

Stokes drift(SD) and Lagrangian discharge(LD) are important factors for analysis of flushing time, tidal exchange, solute transport and pollutant dispersion. The factors should be calculated using the approached method to flow phenomena. The aim of this paper re-examines the previous procedures for computing the SD and LD, and is to propose the new method approached to stratified flow field in the cross-section of coastal region, e.g. Masan Bay. The intensity of velocity near the bottom boundary layer(BBL) depends on the sea-bed irregularity in the coastal estuaries. So we calculated the depth mean velocity(DMV) considering that of BBL omitted in Kjerfve's calculation method. It revealed that BBL effect resulting in application of the bay acts largely on DMV in half more among 1l stations. The new expression of SD and LD per unit width in the cross-section using the developed DMV and proposed decomposition procedure of current were derived as follow : $$Q=u_0+\frac{1}{2}H_1{U_1cos(\varphi_h-\varphi_u)+U_3cos(\varphi_h-\varphi{ud})} LD ED SD$(Q_{skim}+Q_{sk2}) The third term, $Q_{sk2}$, on the right-hand of the equation is showed newly and arise from vertical oscillatory shear. According to the results applied in 3 cross-sections including 11 stations of the bay, the volume difference between proposed and previous SD was founded to be almost 2 times more at some stations. But their mean transport volumes over all stations are 18% less than the previous SD. Among two terms of SD, the flux of second term, $Q_{skim}$, is larger than third term, $Q_{sk2}$, in the main channel of cross-section, so that $Q_{skim}$ has a strong dependence on the tidal pumping, whereas third term is larger than second in the marginal channel. It means that $Q_{sk2}$ has trapping or shear effect more than tidal pumping phenomena. Maximum range of the fluctuation in LD is 40% as compared with the previous equations, but mean range of it is showed 11% at all stations, namely, small change. It mean that two components of SD interact as compensating flow. Therefore, the computation of SD and LD depend on decomposition procedure of velocity component in obtaining the volume transport of temporal and spacial flow through channels. The calculation of SD and LD proposed here can separate the shear effect from the previous SD component, so can be applied to non-uniform flow condition of cross-section, namely, baroclinic flow field.

• Journal of Wetlands Research
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• v.15 no.4
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• pp.509-518
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• 2013

Understanding of the exchange between the water and energy which is happening between the surface and atmosphere is the basic of studying water resources. To study these, lots of researches using Noah Land Surface Model(LSM) are in progress. Noah LSM is based on energy and water balance equation and simulates various hydrological factors. There are diverse researches with Noah LSM are ongoing in overseas, on the other hand not enough study has been done. Especially there is almost no study using uncoupled Noah LSM in Korea. In this study we used data from Korea Flux Tower in Haenam(HFK) and Gwangneung(GDK) as forcing data to simulate the model and compared its result of net radiation, sensible heat flux and latent heat flux with the observation data to assess the applicability of Noah LSM in Korea. Regression coefficients of the comparison results of Noah LSM and observation show good agreement with the value of 0.83~0.99 at Haenam and 0.64~0.99 at Gwangneung which means Noah LSM can be trusted.

• Journal of Korea Multimedia Society
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• v.17 no.2
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• pp.180-190
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• 2014

Social network services are increasingly being used in organizational settings to improve relationships among employees and enhance prospects for information exchange and cooperative work. Social Networking Service(SNS) has deeply penetrated organizational job settings, influencing multiple aspects of employee's life. This study is designed to explore the impact of SNS engagement on the job performance mediated as team cooperation and decision making quality effects. Data were collected from 146 employees who use organizational SNS in there company. Factor analysis and structural equation method are employed. Results from a survey accompanied by the substantial impacts of organizational employee's social networking engagement on social learning processes and outcomes. SNS engagement not only directly influences organizational employee's job performance, but also helps their team cooperation and decision making quality from others and adapt to organizational culture, both of which play prominent roles in improving their job performance.

• Journal of the Korean Magnetics Society
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• v.3 no.3
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• pp.179-184
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• 1993

The X-ray diffraction pattern of amorphous $Fe_{78}Si_{9}B_{13}$ alloy was analyzed to obtain the radial distribution function (RDF) where the first peak was in the form of Gaussian function. The calculated coordination number of the form of Gaussian functiono The calculated coordination number of the sample is 13.5, the mean distance betweeon near-neighbor atoms $r_{0}$ is $2.595{\AA}$ and a Gaussian parametet ${\delta}r$ indicating near-neighbor atomic distri-bution is $0.27{\AA}$. The temperature dependence of saturated magnetization at low temperature could be explained by spin wave excitations theory yielding the spin wave stiffness constant as $117.8\;meV\;{\AA}^2$. Also, we tried to fit the observed temperature dependence of saturated magnetization with the Handrich's equation of the modified molecular field theory for the amorphous ferromagnet. Nice fittings are obtained when we used the parameters ${\Delta}=0.32$(S=1/2) and ${\Delta}=0.23$(S=1), respectively. Finally, the calculated spin wave stiffness constant using the parameters and the structural data are $149\;meV\;{\AA}^2$ for S=1/2 and $138\;meV\;{\AA}^2$ for S=1, respectively. The mean exchange coupling integral between near-neighbor atoms was estimated to be 17.9 meV for S=1/2 and 6.7 meV for S=1.

• Journal of Distribution Science
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• v.13 no.4
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• pp.65-76
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• 2015

Purpose - This article aims to present and test a model regarding franchisors' supporting activities that may positively influence franchisees' attitude toward the franchising headquarter and their own business performance. Moreover, the authors examine the moderating effect of competitive intensity between franchisee attitude and business performance. Most previous research focused on behavioral performance measurements such as satisfaction, trust, and commitment. There are few empirical studies that focus on financial performance data because it is difficult to determine a relational mechanism between behavioral and financial performance. Moreover, financial data is confidential and difficult to collect in many cases. However, this study measures financial performance (e.g., sales revenue per square meter) differently than most previous research, which is mostly focused on the behavioral performance measurements. Research design, data, and methodology - To test our hypotheses, we selected 137 franchisee managers who are running chains of one of the foremost bakery franchise brands in South Korea. This study carefully investigated the reliability, content validity, convergent validity, and discriminant validity of the proposed instrument by analyzing the data obtained from the samples. The data was analyzed using the AMOS structural equation modeling program. Results - The results indicated that: non-financial support activities (e.g., information exchange and communication) had a positive impact on the franchisee attitude toward the franchising headquarter. The franchisee attitude in turn had a positive effect on the headquarters' business performance. Furthermore, competitive intensity could enhance the relationship between franchisee attitude toward franchising headquarter and business performance in a local franchise market. However, financial support activities (e.g., rewards and promotional support) and training had no relationship with either franchisee attitude or business performance. Conclusions - This study provides some practical implications to franchisors in terms of franchise operation and store opening strategies. With respect to the franchise operation strategy, franchisors need to focus on non-financial rather than financial support. Most franchisees consider the necessity of financial support activities and not their sufficiency because these activities are specified in their franchise contract. In addition, it is important for franchisees to maintain a positive attitude for the franchise headquarters. The franchisees with a positive attitude for the franchisor can show a high degree of solidarity for various support activities, and it consequently determines franchisees' sales performance. In terms of franchise store opening strategy, this study suggests an additional criterion that can be considered in determining the location of direct and non-direct management stores (e.g., franchisees' stores). In this research, franchise stores located within high level of competitive intensity are shown to have a high relationship between franchisee attitudes of franchisor support activities and business performance compared to the franchisees located within low competitive intensity level. This result shows that opening non-direct franchise stores is more effective than direct stores in higher competitive market situations. Research contribution, implications, and further research directions are discussed at the end of the paper.

• Journal of Distribution Research
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• v.16 no.1
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• pp.179-222
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• 2011

This research investigates the influence of relational characteristics on 'co-defection', customer defection following salesperson turnover, in the context of salesperson-customer relationship. Based on the social exchange theory, it was hypothesized that perceived relational benefits and switching costs affect directly the customer's intentions to defect. Key constructs in relationship marketing such as customer satisfaction, trust, and loyalty were hypothesized to affect the customer's intention to defect as well as perceived relational benefits and switching costs. The results of structural equation modeling using a survey sample of 503 insurance customers who purchased life insurance policies through salespersons unveiled that the customer satisfaction with salesperson and the customer trust in salesperson strongly influence the salesperson-owned customer loyalty. However, they did not have significant direct effects on co-defection intentions. All paths from salesperson-owned customer loyalty to perceived relational benefits and perceived switching costs were also significant. Salesperson-owned customer loyalty did not have significant direct effects on co-defection intentions, but it had significant indirect effects on co-defection intentions through relational benefits and switching costs. Three sub-dimensions of perceived relational benefits had significant positive effects on co-defection intentions while the perceived switching costs had significant negative effects on co-defection intentions. The significance of our research findings were verified by comparing the hypothesized model and the rival model in the past studies.

• 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.

• Environmental and Resource Economics Review
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• v.23 no.2
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• pp.187-224
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• 2014

We present key issues to consider in estimating damages from price-fixing cases and then apply the procedure addressing those issues to a transportation fuel market. Among the five methods of overcharge calculation, the regression analysis incorporating the yardstick method is the best. If the price equation relates the domestic price to the foreign price and the exchange rate as in the transportation fuel market, the functional form satisfying both logical consistency and modeling flexibility is the log-log functional form. If the data under analysis is of time series in nature, then the ARDL model should be the base model for each market and the regression analysis incorporating the yardstick method combines these ARDL equations to account for inter-market correlation and arrange constant terms and collusion-period dummies across component equations appropriately so as to identify the overcharge parameter. We propose a two-step test for the benchmarked market: (a) conduct market-by-market Spearman or Kendall test for randomness of the individual market price series first and (b) then conduct across-market Friedman test for homogeneity of the market price series. Statistical significance is the minimal requirement to establish the alleged proposition in the world of uncertainty. Between the sensitivity analysis and the model selection process for the best fitting model, the latter is far more important in the economic analysis of damage in price-fixing litigation. We applied our framework to a transportation fuel market and could not reject the null hypothesis of no overcharge.

• KDI Journal of Economic Policy
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• v.32 no.3
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• pp.1-32
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• 2010

The global financial crisis has exerted enormous impacts on the attainment of inflation target in Korea. The annual average CPI inflation was 3.3% during the targeting period of 2007-2009 and the target was $3.0{\pm}0.5%$. Thus Korea has succeeded in keeping annual average CPI inflation just below the upper limit of the 2007-2009 target under the global crisis. This paper intends to evaluate the performance of the inflation targeting system in Korea. First, it estimates the conventional call rate reaction equation under the global crisis and finds that the policy interest rates never reacted to expected inflation, output gap, and won/dollar exchange rate, as expected by theory. Second, it identifies the shock of global financial crisis into core and non-core, applying the structural VAR model. The core shock was defined to have no (medium- to) long-run impact on real output. The core shock was identified to have the character of the demand shock, since it has the positive impact on the inflation and output in the short run. The structural core inflation due to core shock was an attractor of headline inflation, not vice versa. Therefore, the structural core inflation that reflects the demand-side shock would be the better intermediate target for the final headline inflation target than the official core inflation that excludes the volatile inflation of agricultural and oil-related products. During the inflation targeting period of 2007-2009, the structural core inflation was more volatile than the official core inflation, because the global crisis has very large negative impacts on the domestic demand as well as the prices of agricultural and oil-related products. This paper shows that the negative core shock during the fourth quarter of 2008 was larger than that in the financial crisis in 1998. But the core shock turned into positive very quickly in 2009, as the Korean economy recovered very quickly from crisis. The volatile changes in structural core inflation suggests that the Bank of Korea barely managed to attain the 2007-2009 inflation target, owing to the very large negative impacts of the global financial crisis on the domestic demand. It also suggests that the rapid rise in core inflation with the rapid recovery of the Korean economy will lead to rapid rise in headline inflation.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.3
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• pp.137-145
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• 2014

We present a design sensitivity analysis(DSA) method for multiscale problems based on bridging scale decomposition. In this paper, we utilize a bridging scale method for the coupled system analysis. Since the analysis of full MD systems requires huge amount of computational costs, a coupled system of MD-level and continuum-level simulation is usually preferred. The information exchange between the MD and continuum levels is taken place at the MD-continuum boundary. In the bridging scale method, a generalized Langevin equation(GLE) is introduced for the reduced MD system and the GLE force using a time history kernel is applied at the boundary atoms in the MD system. Therefore, we can separately analyze the MD and continuum level simulations, which can accelerate the computing process. Once the simulation of coupled problems is successful, the need for the DSA is naturally arising for the optimization of macro-scale design, where the macro scale performance of the system is maximized considering the micro scale effects. The finite difference sensitivity is impractical for the gradient based optimization of large scale problems due to the restriction of computing costs but the analytical sensitivity for the coupled system is always accurate. In this study, we derive the analytical design sensitivity to verify the accuracy and applicability to the design optimization of the coupled system.