• Environmental and Resource Economics Review
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• v.13 no.1
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• pp.49-82
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• 2004

The study aimed to evaluate cancer damage cost due to risk from benzene inhalation. We performed health risk assessment based on US EPA guideline to estimate annual population risk in Ulsan metropolitan city. Also, we estimated a willingness-to-pay amount for reducing a cancer mortality rate to evaluate a value of statistical life. We combined the annual population risk and the value of statistical life to calculate the cancer damage cost. In the health risk assessment, we applied the benzene unit risk ($2.2{\times}10^{-6}{\sim}7.8{\times}10^{-6}$) in the US EPA'S Integrated Risk Information System to assess the annual population risk. Average concentration of benzene in ambient air is $7.88{\mu}g/m^3$(min: 1.16~max: $23.32{\mu}g/m^3$). We targeted an exposure population of 516,641 persons who aged over 30 years old. Using a Monte-Carlo simulation for uncertainty analysis, we evaluated that the population risk of benzene during ten years in Ulsan city is 2.90 persons (5 percentile: 0.32~95 percentile: 9.11persons). And the monthly average WTP for 5/1,000 cancer mortality reduction during ten years is 14,852 Won(95% C.I: 13,135~16,794 Won) and the implied VSL is 36 million Won(95% C.I: 30~40 million Won). Cancer damage cost due to risk from benzene inhalation during 10 years in Ulsan city is about 104 million Won(5 percentile: 13~95 percentile: 328 million Won). Health benefit cost to reduce a cancer mortality risk of benzene is about 50 million Won is Ulsan metropolitann city. But, it is very important that this cost is not for all health damage cost of cancer mortality in some area. We just recommended a model for evaluating a cancer risk reduction, so we must re-evaluate an integrated application of total VOCs damage cost including benzene.

• Journal of Distribution Research
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• v.13 no.1
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• pp.1-33
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• 2008

As the interest in the business-to-business(B2B) electronic commerce is increasing, many companies are participating in the B2B e-Marketplaces. The e-Marketplace is defined as the virtual market that many players take part in to transact. The e-Marketplace has an influenced on the manner in which organizational buyers and sellers interact. As a result, it is important to develop an understanding of the behaviors of firms that use these electronic marketplaces. The purpose of this study is to develop a comprehensive model for trust and commitment of B2B e-Marketplace and empirically to examine their structural relationships. Drawing from trust and commitment theory in the interorganizational relationship and B2B electronic commerce context, this study identifies network externality, interactivity, justice, quality of information sharing, institutional assurance as the determinants of trust and commitment of e-Marketplace. The proposed model hypothesized that (1) trust is a function of network externality, interactivity, justice, quality of information sharing, institutional assurance, (2) attitudinal and behavioral commitment is a function of trust, (3) behavioral commitment is a function of attitudinal commitment. The proposed model is tested using organizational-level survey data from 187 buying organizations that conduct business in MRO e-Marketplaces. The data were tested by reliability test, correlation analysis, exploratory factor analysis, confirmatory factor analysis and covariance structure analysis. The results indicate that (1) trust is influenced by network externality, interactivity, justice, institutional assurance, (2) attitudinal commitment and behavioral commitment is influenced by trust (3) behavioral commitment is influenced by attitudinal commitment. Also, the empirical results confirmed that trust play a strong, central role in determinging e-Marketplace commitment. The key theoretical contribution of this research is that it begins to extend interorganizational information system literature in areas such as B2B Internet e-Marketplace. Managerially, this study contributes tn the understanding of the role of B2B e-Markeplace providers in Internet situation. And Limitations of this study and guidelines for future researches are also discussed.

• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.652-665
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• 2016

National Competency Standards or NCS is an educational system that emphasizes developing job-related abilities. Therefore it will be an effective solution in training field-oriented work forces if properly applied. However, in the department of social welfare, it is not easy to apply NCS to the curriculum since most academic subjects concerning social welfare focus not on practice but on theory and in addition, most of social welfare departments in junior colleges have an accredited curriculum for the 2nd degree of the social worker qualification. This means it is preposterous if NCS is applied to the curriculum without prior changes in the existing qualification system. So, this paper proposes a draft model to apply NCS to the already-accredited curriculum for the 2nd degree social workers in the junior colleges and details are as follows. Firstly, the competency units will be customized for the existing academic subjects in the curriculum rather than developing new subjects in accordance with NCS competency units. Secondly, some client-related competency units including children, seniors, the disabled are newly developed and then applied to the curriculum, which are crucial for the career development at the junior college level. Thirdly, the competency units are categorized into three types in accordance with the degree of job relevancy - type 1, type 2, type 3. Fourthly, four out of 11 basic job abilities are selected and then developed into academic subjects. Fifthly, all competency units concerning the main job market are regarded as one virtual competency unit and then arranged in the order of type 1s, type 2s and type 3s and then the scope of their study is adjusted to the job abilities required at the main job market.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.947-956
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• 2009

Residual petroleum hydrocarbons after an oil spill may accumulate in the marine benthic ecosystem due to their high hydrophobicity. A lot of monitoring data are required for the estimation of ecosystem exposure to residual petrochemicals in an ecological risk assessment in the affected region. To save time and cost, the environmental exposure to them in the affected ecosystem can also be assessed using a simple food-web bioaccumulation model. In this study, we evaluated residual concentrations of four selected polycyclic aromatic hydrocarbons (phenanthrene, anthracene, pyrene, and benzo[a]pyrene) in a hypothetic benthic ecosystem composed of six species under two exposure scenarios. Body-residue concentration ranged 5~250 mg/kg body depending on trophic positions in an extreme scenario in which the aqueous concentrations of PAHs were assumed to be one-tenth of their aqueous solubility. In addition, bioconcentration factors (BCFs) and bioaccumulation factors (BAFs) were evaluated for model species. The logarithm of bioconcentration factor (log BCF) linearly increased with increasing the logarithm of 1-octanol-water partition coefficient (log $K_{OW}$) until log $K_{OW}$ of 7.0, followed by a gradual decrease with further increase in log $K_{OW}$ without metabolic degradation. Biomagnification became significant when log $K_{OW}$ of a pollutant exceeded 5.0 in the model ecosystem, indicating that investigation of food-web structure should be critical to predict biomagnifications in the affected ecosystem because log $K_{OW}$ values of many petrochemicals are higher than 5.0. Although further research is required for better site-specific evaluation of exposure, the model simulation can be used to estimate the level of the ecosystem exposure to residual oil contaminants at the screening level.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.325-335
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• 2017

This study examined the effects of mothers' smartphone usage habits on young children's aggression and emotional intelligence. For this purpose, a total of 275 questionnaires from mothers in Jeonbuk Province with 3~5 year old young children, who had experiences in using smartphones, were analyzed, and the results are as follows. First, an analysis of the general trend of mother's smartphone usage habits showed that young children's aggression and emotional intelligence according to the general trend of mother's smartphone usage habits had a generally low rate and 'the tolerance and flow' had a high score among its sub-factors. The general trend of young children's aggression also showed a generally low rate, and 'status acquired aggression' had a high score among its sub-factors. The general trend of young children's emotional intelligence showed a moderate level, and a high score was observed in 'mother relation' among its sub-factors. Second, an analysis of the relationship between mother's smartphone usage habits, and young children's aggression and emotional intelligence showed that mother's smartphone usage habits had a positive correlation with the young children's aggression while it did not correlate with the young children's emotional intelligence. On the other hand, a negative correlation was observed between the virtual world orientation among the sub-factors of smartphone usage habits and the self-emotion awareness and expression among the sub-factors of emotional intelligence. Third, an analysis of the effects of mother's smartphone usage habits on children's aggression showed that all of mother's smartphone usage habits and its sub-factors had a negative effect on children's aggression. Fourth, an analysis of the effects of mother's smartphone usage habits on young children's emotional intelligence showed that none of mother's smartphone usage habits or its sub-factors had a significant effect.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.2
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• pp.51-63
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• 2019

Purpose: Radiation therapy for breast cancer should consider the change in breast shape due to breathing and swelling. In this study, we evaluate the benefit of using virtual bolus for IMRT of left breast cancer. Materials and methods: 10 patients with early breast cancer who received radiation therapy after breastconserving surgery compared the VMAT and IMRT plans using the virtual bolus method and without using it. The first analysis compared the V95%, HI, CI of treatment volume, Dmean, V5, V20, V30 of ipsilateral lung, and Dmean of heart in VMAT plan made using the virtual bolus method(VMAT_VB) to the plan without using it(VMAT_NoVB) in case there is no change in the breast. In IMRT, the same method was used. The second analysis compared TCP and NTCP based on each treatment plan in case there is 1cm expansion of treatment volume. Result: If there is no change in breast, V95% in VB Plan(VMAT_VB, IMRT_VB) and NoVB Plan(VMAT_NoVB, IMRT_NoVB) is all over 99% on each treatment plan. V95% in VMAT_NoVB and VMAT_VB is 99.80±0.17% and 99.75±0.12%, V95% in IMRT_NoVB and IMRT_VB is 99.67±0.26% and 99.51±0.15%. Difference of HI, CI is within 3%. OAR dose in VB plan is a little high than NoVB plan, and did not exceed guidelines. If there is 1cm change in breast, VMAT_NoVB and IMRT_NoVB are less effective for treatment. But VMAT_VB and IMRT_VB continue similar treatment effect compared in case no variation of breast. Conclusion: This study confirms the benefit of using a virtual bolus during VMAT and IMRT to compensate potential breast shape modification.

• The KIPS Transactions:PartB
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• v.16B no.5
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• pp.341-346
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• 2009

The motion data glove is a representative human-computer interaction tool that inputs human hand gestures to computers by measuring their motions. The motion data glove is essential equipment used for new computer technologiesincluding home automation, virtual reality, biometrics, motion capture. For its popular usage, this paper attempts to develop an inexpensive visual.type motion data glove that can be used without any special equipment. The proposed approach has the special feature; it can be developed as a low-cost one becauseof not using high-cost motion-sensing fibers that were used in the conventional approaches. That makes its easy production and popular use possible. This approach adopts a visual method that is obtained by improving conventional optic motion capture technology, instead of mechanical method using motion-sensing fibers. Compared to conventional visual methods, the proposed method has the following advantages and originalities Firstly, conventional visual methods use many cameras and equipments to reconstruct 3D pose with eliminating occlusions But the proposed method adopts a mono vision approachthat makes simple and low cost equipments possible. Secondly, conventional mono vision methods have difficulty in reconstructing 3D pose of occluded parts in images because they have weak points about occlusions. But the proposed approach can reconstruct occluded parts in images by using originally designed thin-bar-shaped optic indicators. Thirdly, many cases of conventional methods use nonlinear numerical computation image analysis algorithm, so they have inconvenience about their initialization and computation times. But the proposed method improves these inconveniences by using a closed-form image analysis algorithm that is obtained from original formulation. Fourthly, many cases of conventional closed-form algorithms use approximations in their formulations processes, so they have disadvantages of low accuracy and confined applications due to singularities. But the proposed method improves these disadvantages by original formulation techniques where a closed-form algorithm is derived by using exponential-form twist coordinates, instead of using approximations or local parameterizations such as Euler angels.

• Radiation Oncology Journal
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• v.21 no.4
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• pp.322-329
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• 2003

Purpose: It is difficult to exactly determine the surface dose and the dose distribution In buildup region of high energy X-rays by using the conventional ion chamber. The aim of this study Is to evaluate the accuracy of widely used dosimetry systems to measure the surface dose and the depth of maximum dose (d$_{max}$). Materials and Methods: We measured the percent depth dose (PDD) from the surface to the d$_{max}$ in either a water phantom or in a solid water phantom using TLD-100 chips, thimble type ion chamber, diode detector, diamond detector and Markus parallel plate ion chamber for 6 MV and 15 MV X-rays, 10$\times$10 cm$^{2}$, at SSD=100cm. We analysed the surface dose and the d$_{max}$. In order to verify the accuracy of the TLD data, we executed the Monte Carlo simulation for 5 MV X-ray beams. Results: The surface doses In 6 MV and IS MV X-rays were 29.31% and 23.36% ior Markus parallel plate ion chamber, 37.17$\%$ and 24.01$\%$ for TLD, 34.87$\%$ and 24.06$\%$ for diamond detector, 38.13$\%$ and 27.8$\%$ for diode detector, and 47.92$\%$ and 35.01$\%$ for thimble type ion chamber, respectively. in Monte Carlo simulation for 6 MV X-rays, the surface dose was 36.22$\%$, which Is similar to the 37.17$\%$ of the TLD measurement data. The d$_{max}$ In 6 WV and 15 MV X-rays was 14$\~$16 mm and 27$\~$29 mm, respectively. There was no significant difference in the d$_{max}$ among the detectors. Conclusion: There was a remarkable difference in the surface dose among the detectors. The Markus parallel plate chamber showed the most accurate result. The surface dose of the thimble ion chamber was 10$\%$ higher than that of other detectors. We suggest that the correction should be made when the surface dose of the thimble ion chamber Is used for the treatment planning ion the supeficial tumors. All the detectors used In our study showed no difference in the d$_{max}$.

• Journal of Global Scholars of Marketing Science
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• v.17 no.4
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• pp.113-139
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• 2007

This study aims to, looking from a standpoint of network, has investigated the shipping industry's B2B e-marketplace, the characteristics that can earn electronic trust from the users, and characteristics of the web-site. It has examined the mechanism whereby electronic trust be earned and how it affects web-site involvement and service transaction intention. Ultimately, The study attempts to make proposals whereby such trust can lead for a cooperative trading community in the shipping industry's B2B e-marketplace The Covalence structural equation modeling was designed and empirically tested for the shipping industry's B2B e-marketplace. The shipping industry employees were given questionnaires and data were analyzed. Except for perceived security of the three characteristic factors on the web-site, the perceived site quality and characteristics factors in operation only affected co-variables. Transaction Fairness was determined to be the most important factor among exogenous factors increasing electronic trust. With regards to transaction rules, if a transaction is beneficial only to one side, then no long term transaction will not take place. If the concerned parties properly recognize that transaction fairness is crucial to electronic transaction, then it will enormously contribute to successful operations of shipping e-marketplace. Also, Perceived efficiency in transaction also affects electronic trust. This reduces transaction costs and speeds up and simplifies the transaction process. It has reduced greater time and costs than existing off-line transaction, and would positively affect electronic trust. By making an open forum for participants to obtain information for transaction, they can gather useful information, and at the same time, the web-site operator can provide information, which, in turn, will increase electronic trust in electronic transaction. Furthermore, such formation of trust in electronic transaction influences shipping companies in such a way that they will want to continuously participate in the transaction, raising web-site involvement. The result of increased trust is that shipping companies in the future will do business with each other and form a foundation for continuous transactions amongst themselves. Consequently, the formation of trust in electronic transaction greatly influences web-site involvement and service transaction intention. The results of the study have again proved that in order to maintain continuous business relationship with the current clients, electronic trust in virtual space, which operates the shipping industry's B2B e-marketplace, is important for the interested parties.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.4
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• pp.144-159
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• 2014

Techniques for making a single panoramic image using multiple pictures are widely studied in many areas such as computer vision, computer graphics, etc. The panorama image can be applied to various fields like virtual reality, robot vision areas which require wide-angled shots as an useful way to overcome the limitations such as picture-angle, resolutions, and internal informations of an image taken from a single camera. It is so much meaningful in a point that a panoramic image usually provides better immersion feeling than a plain image. Although there are many ways to build a panoramic image, most of them are using the way of extracting feature points and matching points of each images for making a single panoramic image. In addition, those methods use the RANSAC(RANdom SAmple Consensus) algorithm with matching points and the Homography matrix to transform the image. The SURF(Speeded Up Robust Features) algorithm which is used in this paper to extract featuring points uses an image's black and white informations and local spatial informations. The SURF is widely being used since it is very much robust at detecting image's size, view-point changes, and additionally, faster than the SIFT(Scale Invariant Features Transform) algorithm. The SURF has a shortcoming of making an error which results in decreasing the RANSAC algorithm's performance speed when extracting image's feature points. As a result, this may increase the CPU usage occupation rate. The error of detecting matching points may role as a critical reason for disqualifying panoramic image's accuracy and lucidity. In this paper, in order to minimize errors of extracting matching points, we used $3{\times}3$ region's RGB pixel values around the matching points' coordinates to perform intermediate filtering process for removing wrong matching points. We have also presented analysis and evaluation results relating to enhanced working speed for producing a panorama image, CPU usage rate, extracted matching points' decreasing rate and accuracy.