• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.32.1-32.4
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• 2020

Background: Le Fort I osteotomy is a highly effective treatment for skeletal jaw deformities and is commonly performed. High Le Fort I osteotomy is a modified surgical procedure performed for improving the depression of the cheeks by setting the osteotomy higher than the conventional Le Fort I osteotomy. Developments in three-dimensional (3D) technology have popularized the use of 3D printers in various institutions, especially in orthognathic surgeries. In this study, we report a safe and inexpensive method of performing a high Le Fort I osteotomy using a novel 3D device and piezosurgery, which prevent tooth root injury without disturbing the operation field for patients with a short midface and long tooth roots. Results: A 17-year-old woman presented with facial asymmetry, mandibular protrusion, a short midface, and long tooth roots. We planned high Le Fort I osteotomy and bilateral sagittal split ramus osteotomy. Prevention of damage to the roots of the teeth and the infraorbital nerve and accurate determination of the posterior osteotomy line were crucial for clinical success. Le Fort I osteotomy using 3D devices has been reported previously but were particularly large in size for this case. Additionally, setting the fixing screw of the device was difficult, because of the risk of damage to the roots of the teeth. Therefore, a different surgical technique, other than the conventional Le Fort I osteotomy and 3D device, was required. The left and right parts of the 3D device were fabricated separately, to prevent any interference in the surgical field. Further, the 3D device was designed to accurately cover the bone surface from the piriform aperture to the infra-zygomatic crest with two fixation points (the anterior nasal spine and the piriform aperture), which ensured stabilization of the 3D device. The device is thin and does not interfere with the surgical field. Safe and accurate surgical performance is possible using this device and piezosurgery. The roots of the teeth and the infraorbital nerve were unharmed during the surgery. Conclusions: This device is considerably smaller than conventional devices and is a simple, low-cost, and efficient method for performing accurate high Le Fort I osteotomy.

• Journal of Korea Water Resources Association
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• v.56 no.8
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• pp.471-484
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• 2023

Deep learning models based on generative adversarial neural networks are specialized in generating new information based on learned information. The deep generative models (DGMR) model developed by Google DeepMind is an generative adversarial neural network model that generates predictive radar images by learning complex patterns and relationships in large-scale radar image data. In this study, the DGMR model was trained using radar rainfall observation data from the Ministry of Environment, and rainfall prediction was performed using an generative adversarial neural network for a heavy rainfall case in August 2021, and the accuracy was compared with existing prediction techniques. The DGMR generally resembled the observed rainfall in terms of rainfall distribution in the first 60 minutes, but tended to predict a continuous development of rainfall in cases where strong rainfall occurred over the entire area. Statistical evaluation also showed that the DGMR method is an effective rainfall prediction method compared to other methods, with a critical success index of 0.57 to 0.79 and a mean absolute error of 0.57 to 1.36 mm in 1 hour advance prediction. However, the lack of diversity in the generated results sometimes reduces the prediction accuracy, so it is necessary to improve the diversity and to supplement it with rainfall data predicted by a physics-based numerical forecast model to improve the accuracy of the forecast for more than 2 hours in advance.

• Korean small business review
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• v.31 no.2
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• pp.19-37
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• 2009

The purpose of this research is to explore differences between small and medium-sized companies and large-sized companies in the impact of human resource innovativeness(HRI), learning orientation(LO), and HRI-LO interaction on innovation effect and business performance. Although learning orientation has long been considered as a key factor influencing good performance of a business, little research was devoted to exploring the effect of HRI-LO interaction on innovation effect and business performance. In this study, it is investigated whether there is a synergy effect between innovative human workforce and learning orientation corporate culture, in addition to each by itself, to generate good business performance as well as a success of new innovations in the market. Research hypotheses were as follows, including H1) human resource innovativeness(HRI), learning orientation(LO), and interactions of HRI and LO(HRI-LO interaction) positively affect innovation effect, H2) there is a difference of the effect of HRI, LO, and HRI-LO interaction on innovation effect between large-sized and small-sized companies, H3) HRI, LO, HRI-LO interaction, innovation effect positively affect business performance, and H4) there is a difference of the effect of HRI, LO, HRI-LO interaction, and innovation effect on business performance between large-sized and small-sized companies. Data were obtained from 479 practitioners through a web survey since the web survey is an efficient method to collect a national data at a variety of fields. A single respondent from a company was allowed to participate in the study after checking whether they have more than 5-year work experiences in the company. To check whether a common source bias is existed in the sample, additional data from a convenient sample of 97 companies were gathered through the traditional survey method, and were used to confirm correlations between research variables of the original sample and the additional sample. Data were divided into two groups according to company size, such as 352 small and medium-sized companies with less than 300 employees and 127 large-sized companies with 300 or more employees. Data were analyzed through t-test and regression analyses. HRI which is the innovativeness of human resources in the company was measured with 9 items assessing the innovativenss of practitioners in staff, manager, and executive-level positions. LO is the company's effort to encourage employees' development, sharing, and utilizing of knowledge through consistent learning. LO was measured by 18 items assessing commitment to learning, vision sharing, and open-mindedness. Innovation effect which assesses a success of new products/services in the market, was measured with 3 items. Business performance was measured by respondents' evaluations on profitability, sales increase, market share, and general business performance, compared to other companies in the same field. All items were measured by using 6-point Likert scales. Means of multiple items measuring a construct were used as variables based on acceptable reliability and validity. To reduce multi-collinearity problems generated on the regression analysis of interaction terms, centered data were used for HRI, LO, and Innovation effect on regression analyses. In group comparison, large-sized companies were superior on annual sales, annual net profit, the number of new products/services in the last 3 years, the number of new processes advanced in the last 3 years, and the number of R&D personnel, compared to small and medium-sized companies. Also, large-sized companies indicated a higher level of HRI, LO, HRI-LO interaction, innovation effect and business performance than did small and medium-sized companies. The results indicate that large-sized companies tend to have more innovative human resources and invest more on learning orientation than did small-sized companies, therefore, large-sized companies tend to have more success of a new product/service in the market, generating better business performance. In order to test research hypotheses, a series of multiple-regression analysis was conducted. In the regression analysis examining the impact on innovation effect, important results were generated as : 1) HRI, LO, and HRI-LO affected innovation effect, and 2) company size indicated a moderating effect. Based on the result, the impact of HRI on innovation effect would be greater in small and medium-sized companies than in large-sized companies whereas the impact of LO on innovation effect would be greater in large-sized companies than in small and medium-sized companies. In other words, innovative workforce would be more important in making new products/services that would be successful in the market for small and medium-sized companies than for large-sized companies. Otherwise, learning orientation culture would be more effective in making successful products/services for large-sized companies than for small and medium-sized companies. Based on these results, research hypotheses 1 and 2 were supported. In the analysis of a regression examining the impact on business performance, important results were generated as : 1) innovation effect, LO, and HRI-LO affected business performance, 2) HRI by itself did not have a direct effect on business performance regardless of company size, and 3) company size indicated a moderating effect. Specifically, an effect of the HRI-LO interaction on business performance was stronger in large-sized companies than in small and medium-sized companies. It means that the synergy effect of innovative human resources and learning orientation culture tends to be stronger as company is larger. Referring to these result, research hypothesis 3 was partially supported whereas hypothesis 4 was supported. Based on research results, implications for companies were generated. Regardless of company size, companies need to develop the learning orientation corporate culture as well as human resources' innovativeness together in order to achieve successful development of innovative products and services as well as to improve sales and profits. However, the effectiveness of the HRI-LO interaction would be varied by company size. Specifically, the synergy effect of HRI-LO was stronger to make a success of new products/services in small and medium-sized companies than in large-sized companies. However, the synergy effect of HRI-LO was more effective to increase business performance of large-sized companies than that of small and medium-sized companies. In the case of small and medium-sized companies, business performance was achieved more through the success of new products/services than much directly affected by HRI-LO. The most meaningful result of this study is that the effect of HRI-LO interaction on innovation effect and business performance was confirmed. It was often ignored in the previous research. Also, it was found that the innovativeness of human workforce would not directly influence in generating good business performance, however, innovative human resources would indirectly affect making good business performance by contributing to achieving the development of new products/services that would be successful in the market. These findings would provide valuable managerial implications specifically in regard to the development of corporate culture and education program of small and medium-sized as well as large-sized companies in a variety of fields.

• 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.

• Asia pacific journal of information systems
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• v.18 no.4
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• pp.105-130
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• 2008

Consumers of e-learning market differ from those of other markets in that they are replaced in a specific time scale. For example, e-learning contents aimed at highschool senior students cannot be consumed by a specific consumer over the designated period of time. Hence e-learning service providers need to attract new groups of students every year. Due to lack of information on products designed for continuously emerging consumers, the consumers face difficulties in making rational decisions in a short time period. Increased uncertainty of product purchase leads customers to herding behaviors to obtain information of the product from others and imitate them. Taking into consideration of these features of e-learning market, this study will focus on the online herding behavior in purchasing e-learning contents. There is no definite concept for e-learning. However, it is being discussed in a wide range of perspectives from educational engineering to management to e-business etc. Based upon the existing studies, we identify two main view-points regarding e-learning. The first defines e-learning as a concept that includes existing terminologies, such as CBT (Computer Based Training), WBT (Web Based Training), and IBT (Internet Based Training). In this view, e-learning utilizes IT in order to support professors and a part of or entire education systems. In the second perspective, e-learning is defined as the usage of Internet technology to deliver diverse intelligence and achievement enhancing solutions. In other words, only the educations that are done through the Internet and network can be classified as e-learning. We take the second definition of e-learning for our working definition. The main goal of this study is to investigate what factors affect consumer intention to purchase e-learning contents and to identify the differential impact of the factors between consumers with purchase experience and those without the experience. To accomplish the goal of this study, it focuses on herding behavior and perceived usefulness as antecedents to behavioral intention. The proposed research model in the study extends the Technology Acceptance Model by adding herding behavior and usability to take into account the unique characteristics of e-learning content market and e-learning systems use, respectively. The current study also includes consumer experience with e-learning content purchase because the previous experience is believed to affect purchasing intention when consumers buy experience goods or services. Previous studies on e-learning did not consider the characteristics of e-learning contents market and the differential impact of consumer experience on the relationship between the antecedents and behavioral intention, which is the target of this study. This study employs a survey method to empirically test the proposed research model. A survey questionnaire was developed and distributed to 629 informants. 528 responses were collected, which consist of potential customer group (n = 133) and experienced customer group (n = 395). The data were analyzed using PLS method, a structural equation modeling method. Overall, both herding behavior and perceived usefulness influence consumer intention to purchase e-learning contents. In detail, in the case of potential customer group, herding behavior has stronger effect on purchase intention than does perceived usefulness. However, in the case of shopping-experienced customer group, perceived usefulness has stronger effect than does herding behavior. In sum, the results of the analysis show that with regard to purchasing experience, perceived usefulness and herding behavior had differential effects upon the purchase of e-learning contents. As a follow-up analysis, the interaction effects of the number of purchase transaction and herding behavior/perceived usefulness on purchase intention were investigated. The results show that there are no interaction effects. This study contributes to the literature in a couple of ways. From a theoretical perspective, this study examined and showed evidence that the characteristics of e-learning market such as continuous renewal of consumers and thus high uncertainty and individual experiences are important factors to be considered when the purchase intention of e-learning content is studied. This study can be used as a basis for future studies on e-learning success. From a practical perspective, this study provides several important implications on what types of marketing strategies e-learning companies need to build. The bottom lines of these strategies include target group attraction, word-of-mouth management, enhancement of web site usability quality, etc. The limitations of this study are also discussed for future studies.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.4
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• pp.641-650
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• 2008

One of the most important the success of a food service organization. As a matter of fact, menu functions as a list of product restaurant and a communication tool that facilitates the communication between a restaurant and its customers. Accordingly, many scholars and practitioners have suggested various for menu analysis. Among others, menu analysis methods proposed by Miller, Kasavana & Smith, and Pavesic have been frequently and repeatedly published in the academic literature. However, methods common limitation utilize a two-dimensional approach quadrants. Focusing on this problematic of traditional menu analysis methods, Hayes & Huffman suggested a new menu analysis method goal value analysis. The of this study to the menu analysis technique suggested by Hayes & Huffman using goal value. In this research, the goal value analysis adopted wine restaurant.

• Journal of Distribution Science
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• v.12 no.4
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• pp.41-46
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• 2014

Purpose - This study focused on providing strategic findings that make significant sense for companies that are looking for a future outsourcing strategy. The study analyzes the results of outsourcing in the information logistics systems field and verifies the results through experimental study of the performance delivered by logistics outsourcing types. Research design, data, and methodology - The study sample was assembled based on a random sampling method used to extract the initial 451 companies from a list of Korean distributors, wholesalers, and retailers. Following that sample process, 423 companies were confirmed by verifying their e-mail address and contacts (telephone and fax numbers), and were selected as initial research subjects. We reduced that number to 331 companies for the survey sample through telephone interviews in advance with the 423 companies that were targeted, in order to verify whether they are in the field of outsourcing of information logistics systems. The period of the survey extended from November 10, 2013 to January 10, 2014. The number of collected surveys totaled 181. We reviewed the contents of the survey responses, and reduced the number of research subjects to 175. In this study, we used a standard analysis to investigate whether there is a difference in distribution results based on different types of outsourcing information in the logistics system field and, through T-verification, we investigated whether the difference between distribution results in each group resulting from that standard analysis is statistically significant. Results - These results show that there is a difference in distribution outcome, based upon type of distribution outsourcing. In addition, we determined that they are meaningful results by confirming that, for usability and to improve the capabilities of a third-party logistics service supplier, both the choice of reasonable outsourcing types and the enhancement of various types of alliances are very important success factors. Taken together these study results, with a goal of enhancing the distribution capabilities of a Korean distributor, can be implemented to enhance management results achievable by supplying an information logistics system in the form of strategic outsourcing rather than in the form of simple outsourcing. In addition, the outcomes of logistics distributors in Korea that are using outsourcing in the logistics information systems field show high performance results in commercial endeavors in the following order: competitive, pre-competitive, non-competitive, and pro-competitive. Conclusions - This study focused on providing strategic findings. However, in the case of outsourcing in the field of information logistics systems of Korean distributors, there has been a focus on simple outsourcing rather than on strategic outsourcing; furthermore, there has been a concentration on non-competitive forms instead of pro-competitive forms, which could achieve better distribution results. This discussion is presented in more detail in the analysis results of this study.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.1
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• pp.91-95
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• 2009

The use of stainless steel crowns are indicated for restoration of primary or permanent molars with proximal dental caries, extensive dental caries, or previous pulp treatment with increased danger of tooth fracture. Stainless steel crowns were introduced by Humphrey in 1950. For their improved durability, longevity, and success rate, they have been strongly considered for restoring extensive and multi-surfaced dental caries of molars in pediatric dentistry. However, they also have shortcomings, such as possibility of pulpal exposure or damaging proximal surface of adjacent teeth. In addition, when oversized stainless steel crowns are used, eruption of the adjacent permanent teeth may be disturbed by their prominent margin. As a means to compensate the shortcomings of stainless steel crowns, use of orthodontics bands may be considered. It is an alternative restoration method, where an orthodontic band is placed on a tooth first and cavity is restored with filling material, such as composite resin, glass ionomer, or amalgam. The use of an orthodontic band is indicated for molar restoration with cervical dental caries, extensive dental caries, enamel hypoplasia, or previous pulp treatment. Because it requires shorter chair time compared to stainless steel crown, its application is very useful for children with poor behavior. However, restoration using an orthodontic band requires good oral hygiene after its application. This case report illustrates the conservative restoration of primary molars and permanent molars with extensive dental caries using orthodontic bands.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.679-685
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• 2014

Background Frontal sinus fractures, particularly anterior sinus fractures, are relatively common facial fractures. Many agree on the general principles of frontal fracture management; however, the optimal methods of reduction are still controversial. In this article, we suggest a simple reduction method using a subbrow incision as a treatment for isolated anterior sinus fractures. Methods Between March 2011 and March 2014, 13 patients with isolated frontal sinus fractures were treated by open reduction and internal fixation through a subbrow incision. The subbrow incision line was designed to be precisely at the lower margin of the brow in order to obtain an inconspicuous scar. A periosteal incision was made at 3 mm above the superior orbital rim. The fracture site of the frontal bone was reduced, and bone fixation was performed using an absorbable plate and screws. Results Contour deformities were completely restored in all patients, and all patients were satisfied with the results. Scars were barely visible in the long-term follow-up. No complications related to the procedure, such as infection, uncontrolled sinus bleeding, hematoma, paresthesia, mucocele, or posterior wall and brain injury were observed. Conclusions The subbrow approach allowed for an accurate reduction and internal fixation of the fractures in the anterior table of the frontal sinus by providing a direct visualization of the fracture. Considering the surgical success of the reduction and the rigid fixation, patient satisfaction, and aesthetic problems, this transcutaneous approach through a subbrow incision is concluded to be superior to the other reduction techniques used in the case of an anterior table frontal sinus fracture.

• Archives of Reconstructive Microsurgery
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• v.5 no.1
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• pp.35-45
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• 1996

After transplantation of groin free flap was sucessed by the Daniel and Taylor in 1973, the reconstruction of plastic surgery was extensive and universal due to rapidly developement of anatomic study of the donor site and technique of microvascular surgery. The free tissue transfers is possible to be early activity and rehabilitation by one stage operation. It currently available allow transfer of specific tissue quality as bone, muscle, nerve to achieve a functional and cosmetic result as well as the most favorable secondary defect. But free flaps require critical, skillful technique and lengthy operating time. Also it has disadvantage of donor site morbity at the large tissue transfer. Authors were transferred with 107 cases in 103 patients from May 1987 to June 1996, and then we analysed free tissue transfer to acquire more increased sucess rate, satisfactory functional and cosmetic results. The sexual distribution was male prominent in 79 cases(76.7%), female in 24(23.3%) and age was variable distribution from 3 to 76 years old. The cause of defects was most prevalent in trauma of traffic and industrial accident in 51 cases(49%). The common recipient site were lower extremities in 47 cases(43.9%), upper extremities in 28 cases(26.5%), head and neck in 25 cases(23.4%), and trunk in 7 cases(6.5%). The type of transfer were free skin flaps in 46 cases(43%), free muscle or musculocutaneous flaps in 31 cases(29%), free vasculized or osteocutaneous flaps in 10 cases(9.3%), and specilized free flaps in 20 cases(18.7%). The anastomosis of artery was end to end anastomosis in 94 cases(87.9%), end to side anastomosis in 13 cases(12.1%) and all vein was end to end anastomosis. The number of anastomosed vessels were one artery one vein in 62 cases(57.9%), one artery two vein in 45 cases(42.1%) and vein graft was performed only one case. The postoperative mornitoring were used with temperature, color of flap, capillary refilling time, ultrasonogram, bone scan, doppler, and endoscopy. The reexploration was performed in 9 cases(8.4%), and then flap was loss in 3 cases(2.8%). Accordingly overall success rate was 97.2%. The postoperative complication was early vascular occlusion, hematoma, partial necrosis and late bulkiness, scarring, color dismatch etc. Therefore, free tissue transfer is the preferred method of treatment, even through conventional local and distant flaps are available.