• Asia pacific journal of information systems
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• v.19 no.2
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• pp.139-155
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• 2009

For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.2
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• pp.313-320
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• 2014

Purpose : The purpose of the study is to evaluate the efficiency of Coaxial MLC VMAT plan (Using $273^{\circ}$ and $350^{\circ}$ collimator angle) That the leaf motion direction aligned with axis of OAR (Organ at risk, It means spinal cord or cauda equine in this study.) compare to Universal MLC VMAT plan (using $30^{\circ}$ and $330^{\circ}$ collimator angle) for spine SBRT. Materials and Methods : The 10 cases of spine SBRT that treated with VMAT planned by Coaxial MLC and Varian TBX were enrolled. Those cases were planned by Eclipse (Ver. 10.0.42, Varian, USA), PRO3 (Progressive Resolution Optimizer 10.0.28) and AAA (Anisotropic Analytic Algorithm Ver. 10.0.28) with coplanar $360^{\circ}$ arcs and 10MV FFF (Flattening filter free). Each arc has $273^{\circ}$ and $350^{\circ}$ collimator angle, respectively. The Universal MLC VMAT plans are based on existing treatment plans. Those plans have the same parameters of existing treatment plans but collimator angle. To minimize the dose difference that shows up randomly on optimizing, all plans were optimized and calculated twice respectively. The calculation grid is 0.2 cm and all plans were normalized to the target V100%=90%. The indexes of evaluation are V10Gy, D0.03cc, Dmean of OAR (Organ at risk, It means spinal cord or cauda equine in this study.), H.I (Homogeneity index) of the target and total MU. All Coaxial VMAT plans were verified by gamma test with Mapcheck2 (Sun Nuclear Co., USA), Mapphan (Sun Nuclear Co., USA) and SNC patient (Sun Nuclear Co., USA Ver 6.1.2.18513). Results : The difference between the coaxial and the universal VMAT plans are follow. The coaxial VMAT plan is better in the V10Gy of OAR, Up to 4.1%, at least 0.4%, the average difference was 1.9% and In the D0.03cc of OAR, Up to 83.6 cGy, at least 2.2 cGy, the average difference was 33.3 cGy. In Dmean, Up to 34.8 cGy, at least -13.0 cGy, the average difference was 9.6 cGy that say the coaxial VMAT plans are better except few cases. H.I difference Up to 0.04, at least 0.01, the average difference was 0.02 and the difference of average total MU is 74.1 MU. The coaxial MLC VMAT plan is average 74.1 MU lesser then another. All IMRT verification gamma test results for the coaxial MLC VMAT plan passed over 90.0% at 1mm / 2%. Conclusion : Coaxial MLC VMAT treatment plan appeared to be favorable in most cases than the Universal MLC VMAT treatment planning. It is efficient in lowering the dose of the OAR V10Gy especially. As a result, the Coaxial MLC VMAT plan could be better than the Universal MLC VMAT plan in same MU.

• The Journal of Korean Society for Radiation Therapy
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• v.27 no.1
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• pp.45-52
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• 2015

Purpose : The dose distribution of organ at risk (OAR) and normal tissue is affected by treatment technique in postoperative radiation therapy for prostate cancer. The aim of this study was to compare dose distribution characteristic and to evaluate treatment efficiency by devising VMAT plans according to applying differed number of arc and IMRT plan for postoperative patient of prostate cancer radiation therapy using a rectal balloon. Materials and Methods : Ten patients who received postoperative prostate radiation therapy in our hospital were compared. CT images of patients who inserted rectal balloon were acquired with 3 mm thickness and 10 MV energy of HD120MLC equipped Truebeam STx (Varian, Palo Alto, USA) was applied by using Eclipse (Version 11.0, Varian, Palo Alto, USA). 1 Arc, 2 Arc VMAT plans and 7-field IMRT plan were devised for each patient and same values were applied for dose volume constraint and plan normalization. To evaluate these plans, PTV coverage, conformity index (CI) and homogeneity index (HI) were compared and $R_{50%}$ was calculated to assess low dose spillage as per treatment plan. $D_{25%}$ of rectum and bladder Dmean were compared on OAR. And to evaluate the treatment efficiency, total monitor units(MU) and delivery time were considered. Each assessed result was analyzed by average value of 10 patients. Additionally, portal dosimetry was carried out for accuracy verification of beam delivery. Results : There was no significant difference on PTV coverage and HI among 3 plans. Especially CI and $R_{50%}$ on 7F-IMRT were the highest as 1.230, 3.991 respectively(p=0.00). Rectum $D_{25%}$ was similar between 1A-VMAT and 2A-VMAT. But approximately 7% higher value was observed on 7F-IMRT compare to the others(p=0.02) and bladder Dmean were similar among the all plan(P>0.05). Total MU were 494.7, 479.7, 757.9 respectively(P=0.00) for 1A-VMAT, 2A-VMAT, 7F-IMRT and at the most on 7F-IMRT. The delivery time were 65.2sec, 133.1sec, 145.5sec respectively(p=0.00). The obvious shortest time was observed on 1A-VMAT. All plans indicated over 99.5%(p=0.00) of gamma pass rate (2 mm, 2%) in portal dosimetry quality assurance. Conclusion : As a result of study, postoperative prostate cancer radiation therapy for patient using a rectal balloon, there was no significant difference of PTV coverage but 1A-VMAT and 2A-VMAT were more efficient for dose reduction of normal tissue and OARs. Between VMAT plans. $R_{50%}$ and MU were little lower in 2A-VMAT but 1A-VMAT has the shortest delivery time. So it is regarded to be an effective plan and it can reduce intra-fractional motion of patient also.

• The Korean Journal of Air & Space Law and Policy
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• v.24 no.2
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• pp.69-104
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• 2009

This study is to know the Enhancement of Aviation Safety for Low Cost Carrier in Korea through the long and mid term air safety policy. Especially, the aviation safety authorities of the developed countries in aviation establish action plans under the system plan of central government. Then the countries implement those plans systematically to the related aviation business so that they promote efficient air safety policy implementation. At this time, the Korean government should present the vision about an air safety and systematic strategic plan to cope with the future aviation industry change. Also, it is needed to establish a specific aviation safety action plan. Namely, an air safety master plan and long-term road map must be established. This paper deduces some implications through the abroad cases of aviation safety plan, and then tries to find the applying method of the implications to Korea in the rapidly changing aviation market in the 21st century. It is expected that this paper will help the Korean aviation industry to play a major role in the future. In oder to get suggestions aviation policies of advanced countries with regard to aviation safety, we have looked at the aviation policies of the U.S., the U.K., Australia and Japan, and also LCC's states overseas, LCC's safety policies in Korea, and aviation safety status. Since existing LCCs and new LCCs based in Korea have become the new concept, this new market for LCC has been booming recently. Around Southeast Asia, while there are some LCCs including Air Asia which is supported by the government of Malaysia with emphasis on safety, there are other LCCs, which have failed to achieve confidence in safety and have led to aircraft accidents and financial mismanagement, so we need to verify the safety of overseas LCCs, try to improve domestic LCCs in order to fly international routes and aid international aviation safety. LCCs have been increasing lately thanks to open skies policy and a wide variety of flights.lines. Air Busan, Jin Air, Jeju air, Eastar Air are in service. so the risk of new potential hazards may increase. Therefore it is necessary to take the initiative in aviation markets inside and outside of Korea and the safety management of new LCCs should be taken more seriously than ever before. Among overseas aviation safety policies, we need to implement the FAA's Filght Plan which has a specific Business Plan. I hope this thesis will help improve aviation safety locally and internationally.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.4
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• pp.77-85
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• 2014

A goal of Bizcool entrepreneurship education targeting on the youth falls on letting understand the process of starts-up, enhance entrepreneurship will and their business creativities rather than training trivial starts-up skills such as writing business plan for successful starts-up. The effects of education enable Bizcoo students to recognize rightly the concept of starts-up training and lead to spread out demand for entrepreneurship education. The feedback check-up for how entrepreneurship education affects students getting through of it is necessary and possible to bring its' improvement alternatives. Despite of such highlight, not many measuring tools and indexes of evaluating an effectiveness of entrepreneurship education are developed and studied up until. This research suggests for the optimal indexes for them. In specific, this research 49 the first question sets of evaluating an effectiveness of entrepreneurship education classified 3 large categories and 11 following sub categories each of them such as entrepreneurship orientation, creativity, entrepreneurship preparing activities etc,. representing embedding education effects though entrepreneurship education. This research carry out the empirical survey research utilizing driven question sets against 5 different Bizcools sampling 287 students. The survey research delivers the final 3 large categories and 8 following sub categories(Innovativeness, risk-taking, problem-solving potent, cooperative decision-making potent, efficient behavior capacity, data collecting potent, career search, starts-up search and preparation), and 38 measuring indexes by search and confirming factor analysis. This research never drop the confidence test over each indexes and obtain the proper figures. Last but not least, this research confirm the gap between starts-up club members and non members as to an effectiveness of entrepreneurship education and 9 different indexes.

• The Journal of Small Business Innovation
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• v.19 no.2
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• pp.53-68
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• 2016

Motivation and activities for technological learning, entrepreneurship, innovation, and creativity are driving forces of economic development in Asian countries. In the early stages of technological development, technological learning and entrepreneurship are efficient ways in which to catch up with advanced countries because firms can accumulate skills and knowledge quickly at relatively low risk. In the later stages of technological development, however, innovation and creativity become more important. This study aims to identify a) the factors (learning capabilities) that influence technological learning performance and b) barriers to enhancing innovation capabilities for the creative economy and organizations. The major part of this study is related to learning capabilities in the post-catch-up era. Based on a literature review and observations from Korean experiences, this study proposes a technological learning model composed of various influencing factors on technological learning. Three hypotheses are derived, and data are collected from Korean machine tool manufacturers. Intense interviews with CEOs and R&D directors are conducted using structured questionnaires. Statistical analysis, such as correlation and ANOVA are then carried out. Furthermore, this study addresses how to enhance innovation capabilities to move forward. Innovation enablers and barriers are identified by case studies and policy analysis. The results of the empirical study identify several levels of firms' learning capabilities and activities such as a) stock of technology, b) potential of technical labor, c) explicit technological efforts, d) readiness to learn, e) top management support, f) a formal technological learning system, g) high learning motivation, h) appropriate technology choice, and i) specific goal setting. These learning capabilities determine firms' learning performance, especially in the early stages of development. Furthermore, it is found that the critical factors for successful technological learning vary along the stages of technology development. Throughout the statistical and policy analyses, this study confirms that technological learning can be understood as an intrinsic principle of the technology development process. Firms perform proactive and creative learning in the late stages, while reactive and imitative learning prevails in the early stages. In addition, this study identifies the driving forces or facilitating factors enhancing innovation performance in the post catch-up era. The results of the preliminary case studies and policy analysis show some facilitating factors such as a) the strategic intent of the CEO and corporate culture, b) leadership and change agents, c) design principles and routines, d) ecosystem and collaboration with partners, and e) intensive R&D investment.

• Journal of radiological science and technology
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• v.29 no.3
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• pp.167-175
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• 2006

With the recent prevalence of helical CT and multi-slice CT, which deliver higher radiation dose than conventional CT due to overbeaming effect in X-ray exposure and interpolation technique in image reconstruction. Although multi-detector and helical CT scanner provide a variety of opportunities for patient dose reduction, the potential risk for high radiation levels in CT examination can't be overemphasized in spite of acquiring more diagnostic information. So much more concerns is necessary about dose characteristics of CT scanner, especially dose efficient design as well as dose modulation software, because dose efficiency built into the scanner's design is probably the most important aspect of successful low dose clinical performance. This study was conducted to evaluate z-axis geometric dose efficiency in single detector CT and each level multi-detector CT, as well as to compare z-axis dose efficiency with change of technical scan parameters such as focal spot size of tube, beam collimation, detector combination, scan mode, pitch size, slice width and interval. The results obtained were as follows ; 1. SDCT was most highest and 4 MDCT was most lowest in z-axis geometric dose efficiency among SDCT, 4, 8, 16, 64 slice MDCT made by GE manufacture. 2. Small focal spot was 0.67-13.62% higher than large focal spot in z-axis geometric dose efficiency at MDCT. 3. Large beam collimation was 3.13-51.52% higher than small beam collimation in z-axis geometric dose efficiency at MDCT. 4. Z-axis geometric dose efficiency was same at 4 slice MDCT in all condition and 8 slice MDCT of large beam collimation with change of detector combination, but was changed irregularly at 8 slice MDCT of small beam collimation and 16 slice MDCT in all condition with change of detector combination. 5. There was no significant difference for z-axis geometric dose efficiency between conventional scan and helical scan, and with change of pitch factor, as well as change of slice width or interval for image reconstruction. As a conclusion, for reduction of patient radiation dose delivered from CT examination we are particularly concerned with dose efficiency of equipment and have to select proper scanning parameters which increase z-axis geometric dose efficiency within the range of preserving optimum clinical information in MDCT examination.

• Korean Security Journal
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• no.7
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• pp.95-124
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• 2004

It can be said that 'the September 11th Terrorist Attacks' in 2001 were not only the indiscriminate attacks on innocent people but also the whole - political, economical and military - attacks on human life. Also, 'the September 11th Terrorist Attacks' can be regarded as the significant events in the history of world, which were on the peak of the super-terrorism or new-terrorism that had emerged from the 1980s. However, if one would have analysed the developments of terrorism from the 1970s, they could have been foreknown without difficulty. The finding from this study can be summarized as the followings, First, in spite that the USA responsive system against terrorism had been assessed as perfect before 'the September 11th Terrorist Attacks', the fragilities were found in the aspects of the response on the new-terrorism or super-terrorism. The previous responsive system before 'the September 11th Terrorist Attacks' had the following defects as the followings: (1) it was impossible to establish the integrated strategy, because the organizations related to the response against terrorism had not integrated; (2) there were some weakness to collect and diffuse the informations related to terrorism; (3) the security system for the domestic airline service in USA and the responsive system of air defense against terrors on aircraft were very fragile. For these reasons, USA government established the 'Department of Homeland Security' of which the President is the head so that the many organizations related to terrorism were integrated into a single management system. And, it legislated a new act to protect security from terrors, which legalized of the wiretapping in spite of the risk of encroachment upon personal rights, increased the jail terms upon terrorists, froze the bank related to terrorist organization, and could censor e-mails. Second, it seem that Korean responsive system against terrors more fragile than that of USA. One of the reasons is that people have some perception that Korea is a safe zone from terrors, because there were little attacks from international terrorists in Korea. This can be found from the fact that the legal arrangement against terrorism is only the President's instruction No. 47. Under this responsive system against terrorism dependent on only the President's instruction, it is expected that there would be a poor response against terrors due to the lack of unified and integrated responsive agency as like the case of USA before 'the September 11th Terrorist Attacks'. And, where there is no legal countermeasure, it is impossible to expect the binding force on the outside of administrative agencies and the performances to prevent and hinder the terrorist actions can not but be limited. That is to say, the current responsive system can not counteract effectively against the new-terrorism and super-terrorism. Third, although there were some changes in Korean government's policies against terrorism. there still are problems. One of the most important problems is that the new responsive system against terrorism in Korea, different from that of USA, is not a permanent agency but a meeting body that is organized by a commission. This commission is controled by the Prime Minister and the substantial tasks are under the National Intelligence Service. Under this configuration, there can be the lack of strong leadership and control. Additionally, because there is no statute to response against terrorism, it is impossible to prevent and counteract effectively against terrorism. The above summarized suggests that, because the contemporary super-terrorism or new-terrorism makes numerous casualties of unspecified persons and enormous nationwide damages, the thorough prevention against terrorism is the most important challenge, and that the full range of legal and institutional arrangements for the ex post counteraction should be established. In order to do so, it is necessary for the government to make legal and institutional arrangements such as the permanent agency for protection from terrorism in which the related departments cooperates with together and the development of efficient anti-terror programs, and to show its willingness and ability that it can counteract upon any type of domestic and foreign terrorism so that obtain the active supports and confidence from citizens.

• 아동간호학회:학술대회논문집
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• 1997.11a
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• pp.61-74
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• 1997

Endotracheal suctioning is a routine procedure used for clearing secretions from the airway of the intubated infant. This procedure is not without complications. Endotracheal suctioning has been associated with decreases in $PaO_2$, decreases in systemic venous oxygenation, alterations in mean arterial Pressure, disturbances in cardiac rhythm and development of nosocomial pneumonia. So several endotracheal suctioning techniques have been developed to prevent these blown complications. Another method of Endotracheal suctioning eliminates the risk associated with disconnecting the infant from the ventilatior to perform the suctioning procedure. Studies examining closed endotracheal suctioning methods reported that the closed method results in less arterial oxygen saturation, and less systemic venous oxygen desaturation. However those studies have focused on adult patients, and there have been no published studies for newborn infants. The specific purpose of this study is to investigate the two methods and to make a comparison in terms of (1)variations in $SaO_2$, heart rate, and respiration rate appeared before and after the endotracheal suctioning; (2)difference in occurrence of nosocomial infection; (3)difference in recovery time to arrive at pre-suction baseline after suctioning and in nursing time taken for the suctioning. The present study is based on the data obtained from two groups of newborn infants : one group comprises 8 infants with closed suctioning (a total of 304 suctions) among 17 infants treated with ventilator and the other group 9 infants with open method (a total of 629 suctions). The data were analyzed using the SPSS statistical program package. As the distribution test on dependent variables with the Skewnesser Shapiro Wilk test showed an asymmetric distribution, the Wilcoxon Matched-pairs Singled- Ranks test was used for the test of variations in $SaO_2$, heart rate, and respiration rate appeared before and after the endotracheal suctioning. The difference in $SaO_2$ recovery time and nursing time was analyzed with the Mann-Whitney U-Test. The difference in physiologic consequences and occurrence of nosocomial infection between the two groups was analyzed with the Fisher's Exact Test. The results of the study are summarized as follows. For the hypothesis 1 (There would be a difference in $SaO_2$, heart rate, and respiration rate before and after suctioning between the two suctioning methods), the difference in $SaO_2$ turns out to be statistically significant (P=0.015), but heart rate and respiration rate do not procedure a notable difference (P=0.630). The hypothesis 2 (There would be a difference in rates at which a complication arises after suctioning between the two groups) does not prove to be statistically valid (P=0.246). For the hypothesis 3(There would be a difference in $SaO_2$ recovery time and nursing time between the two groups), the average $SaO_2$ recovery time after suctioning turned out to have somewhat significant difference (P=0.064), however the difference in nursing time taken for the suctioning was not statistically significant (P=0.610). The analyses indicate that the closed endotracheal suctioning is more efficient as compared with the open method, in maintaining pre-suction baseline $SaO_2$ and a rapid recovery of newborn infants. Based on these results we suggust to apply the closed method to newborn infants in the ventilation treatment. We also suggest to extend the investigation to include the comparison of suction cost taking into account the case in which a complication arises after endotracheal suctioning between the two groups.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.2
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• pp.201-219
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• 2014

The Republic of Korea in the real economy to a knowledge economy, and a center of creativity and imagination in the creative economy is changing the paradigm. As the core of creating economic, creative industries with the technology and information play an important role in the industry individuals. In order to solve the problem of the polarization of the economy and high youth unemployment rate of Korea, to recognize the role of the creative industries, as objection part, dimensions pan-national and one creative companies in industries of Mobile Apps various policies that support has been promoted. Support these policies to be able to contribute to the establishment of the success of mobile apps one-person creating company, we performed this study targeting one-person company that creates mobile apps area, we conducted a demonstration study of success factors, and thus more effective and efficient in an attempt to seek out support measures. In this study, we derive a research 4 hypothesis about the success factors of one creative enterprise through literature discussion, a study was made on the basis of empirical data of one-person company that creates mobile apps. The results of the analysis, first, if the development rate of the mobile application technology is fast and a new competition associated product is appeared, it was possible to find a tendency to be higher at the performance quantitative companies. Second, if the founder is a founding for the benefit and rewarding work and come to terms with the risk, it was possible to discover tends to be higher achievement quantitative. Third, if one-person company select a target market with capture intensively, it was possible to find a tendency for higher qualitative results. Fourth, it could be found that the reliability of the contact frequency of the network related performance business environment these characteristics enterprise management strategy and act as a significant modulatory effect. Provision of information relating to management and entrepreneurship education to be one creative enterprise is required, these results suggest that there is a provision continuing need for the opportunity to be able to meet and network and reliable variety have. In this study, to take advantage to promote the elimination measures that can increase the likelihood of success of the company of institutions to support one company that creates knowledge-based, such as in the field of mobile application.