• Journal of Advanced Navigation Technology
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• v.27 no.5
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• pp.658-665
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• 2023

Take-off weight is a key factor for improving accuracy when estimating an aircraft's carbon emissions and fuel consumption. However, the takeoff weight contains sensitive payload information that can infer the airline's management strategy, making it impossible to leak it outside. Although several models for estimating takeoff weight have been presented in previous studies, the researcher points out that there are limitations of the study caused by variables at the pilot's discretion. In this paper, several variables related to takeoff weight are identified to suggest a way to control these limits. Among them, variables that can improve the accuracy of takeoff weight are selected and an estimation equation is presented by applying them to ADS-B information. The proposed estimation does not estimate the average takeoff weight but has the advantage of being able to estimate all ranges of the takeoff weight.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.spc
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• pp.79-88
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• 2023

This research aims to validate the effectiveness of the "Specialized Entrepreneurship University Program," which was conducted as part of government entrepreneurship support initiatives from 2018 to 2022. Based on previous studies, a research model was derived consisting of three laboratory entrepreneurship support factors that influence program satisfaction and entrepreneurial outcomes (infrastructure support, educational mentoring support, and business linkage support). Surveys were collected and analyzed from 126 laboratory entrepreneurship firms participating in the program, and empirical analysis of the research model was conducted using SPSS 23.0 statistical software. The analysis results indicated that the three variables, namely infrastructure support, educational mentoring support, and business linkage support, were significant factors affecting program satisfaction, and program satisfaction was confirmed to influence entrepreneurial outcomes. Furthermore, it was found that the three business operation factors indirectly influenced entrepreneurial outcomes by partially mediating program satisfaction. This study is considered significant as an empirical study for the initial stage of the second-phase program enhancement, verifying the effectiveness of laboratory entrepreneurship support factors. The findings can be applied to similar government entrepreneurship support initiatives and contribute to the effective strategy and planning of stakeholders involved. The limitations of this study include the need for further research on the perception of the extent to which it contributes to entrepreneurial outcomes, emphasizing caution in interpreting the research model, and the necessity for expanding the survey population and improving survey items in future research.

• Journal of the Korea Society of Computer and Information
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• v.28 no.12
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• pp.289-296
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• 2023

The purpose of this study aims to identify the key factors that contribute to successful online learning experiences for college students in the pre-course, during course, and post-course phases. A survey was conducted college students, and a total of 95 questionnaires were used for statistical analysis. The main findings revealed that in the pre-course phase, task value, academic self-efficacy, and control beliefs were significant factors. During course, interaction emerged as a crucial factor. Notably, students' satisfaction in the post-course phase is significantly influenced by academic self-efficacy and interaction. Understanding these factors will help inform the design and operation of effective college-level online courses to improve student experience and satisfaction.

• Journal of Chest Surgery
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• v.35 no.12
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• pp.862-870
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• 2002

The surgical results of the patients with single ventricle(SV) associated with total anomalous pulmonary venous connection(TAPVC) has been reported with high mortality and morbidity due to their morphologic and hemodynamic complexity. A retrospective review was undertaken to report the outcome of the first-stage palliative surgery in our institution and to determine the factors influencing early death. Material and Method: Between January 1987 and June 2002, 39 patients with SV and TAPVC underwent surgical intervention with or without TAPVC repair. Age at operation ranged from 1day to 10.7months (median age, 2.4month), and 29 patients were male. Preoperative diagnosis included 20 right-dominant SV, 15 SV with endocardial cushion defect, 3 left-dominant SV, and 1 tricuspid atresia. The pulmonary venous connection was supracardiac in 22, cardiac in 5, infracardiac in 11, and mixed in 1, Obstructed TAPVC was present in 11. First-stage palliative surgery was performed in 37. Repair of TAPVC, either alone or in association with other procedures, was performed during the initial operation in 31. Univariate and multivariate analyses were performed to analyze the risk factors influencing the operative death. Result: A mean follow-up period of survivors was 34.3 $\pm$ 43.0(0.53 ~ 146.2)months. Overall early operative mortality was 43.6%(17/39). The causes were low cardiac output in 8, failure of weaning from cardiopulmonary bypass in 3, sepsis in 2, pulmonary hypertensive crisis in 1, pulmonary edema in 1, pneumonia in 1, and postoperative arrhythmia in 1. Risk factors influencing early death in univariate analysis were body weight, surgical intervention in neonate, obstructive TAPVC, preoperative conditions including metabolic acidosis, and need for inotropic support, TAPVC repair in initial operation, operative time, and cardiopulmonary bypass(CPB) time. In multivariable analysis, body weight, age at initial operation, surgical intervention in neonate, preoperative conditions including metabolic acidosis, need for inotropic support and CPB time were the risk factors. Conclusion: In this study, we demonstrated that the patients with SV and TAPVC had high perioperative mortality. Preoperative poor condition, young age, the length of operative and CPB time, the presence of obstructive TAPVC had been proven to be the risk factors. This fact suggests that the avoidance of unnecessarily additional procedures may improve the surgical outcomes of the first-stage palliative surgery. However further observation and collection of the data is mandatory to determine the ideal surgical strategy.

• Journal of Chest Surgery
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• v.35 no.1
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• pp.36-42
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• 2002

Background: To evaluate the efficiency of surgical treatment in patients with cardiac valvular and arterial involvement of Behcet's syndrome. Material and Method: 12 patients underwent surgical treatment due to the valvular heart diseases and the various arterial diseases associated with Behest's syndrome over 7 years; 6 with valvular heart disease, 1 with annuloaortic ectasia, 1 with ascending aortic aneurysm, 4 with pseudoaneurysms in abdominal aorta(n=2), carotid artery(n=1), and popliteal artery(n=1). All 12 patients had received valvular replacement(n=6) and the artificial(n=5) or autologous(n=1) graft interposition. We followed the results of these surgical treatments. Result: Operations were technically successful in all 12 patients and peri-operative complication was not demonstrated. However, 10 patients had recurrences; 6 with valvular dehiscence, 3 with pseudoaneurysm at anastostomosis site, and 1 with aorto-duodenal fistula. The duration of recurrence was 1 to 55 months(mean: 15.7$\pm$ 16.2 months). 7 patients underwent the second operation and among them, 4 patients showed repeated recurrences. Overall, 5 patients died 2 to 25 months after the operation(mean: 13.6 months), because of the bleeding at the anastomosis site Five patients did not present recurrence after the first(n=2) or the second operation(n=3) and their follow up duration was 5 to 60 months(mean: 45.8$\pm$41.7 months). Five patients received immune-suppressive therapy after the first(n=2) and second operation(n=3). Three did not shown recurrence for the 13, 29 and 33 months. Conclusion: Post-operative prognosis of arterial manifestation of Behcet's syndrome was not encouraging and if possible, other treatment strategy should be considered.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.4
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• pp.105-113
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• 2003

Successful operation of a reactor can be accomplished when it is operated at proper D depending on the state of degradation. Operation at high D leads to the washout of biomass in the reactor while operation at low D leads to product inhibition due to the accumulation of excess VFA. These appear to limit the production of hydrogen to reach a higher level. Operation by D control was performed to improve the efficiency of hydrogen fermentation of food waste. Although simple organic matters were rapidly degraded in the early stage (day 1-2), proper VFA concentration and pH values were kept in the reactor at D of $4.5d^{-1}$, which was previously reported to be optimum initial D. High butyrate/acetate (B/A) ratios over 3.2 were obtained. Without D control, the reduction of simple organic matters after day 2 caused the decrease of VFA production and the increase of pH. Hydrogen production also decreased, as microbial proliferation was less than microbial loss by washout. However, the reactor performance was dramatically improved at D control from 4.5 to $2.3d^{-1}$. It showed the highest B/A ratios over 2.0 among the reactors on day 4-7. The second hydrogen peak appeared on day 4, resulting in the highest fermentation efficiency (70.8%) among the reactors. It was caused by the enhanced degradation of slowly degradable matters. The COD removed was converted to hydrogen (19.3%), VFA (36.5%), and ethanol (15.0%). Therefore, the strategy using D control, depending on the state of degradation, was effective in improving the efficiency of hydrogen fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.815-822
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• 2006

The purposes of this study were to investigate the consumer's perception of the subject to manage the foodservice operation in the university, and to analyze the effects of consumer's perception of the university foodservice qualify on intent to revisit and intent to recommend. The questionnaires were distributed to 575 students in the K University located in Masan, who were sampled by proportionate stratified sampling method. The surveys were peformed from May 17 to June 2, 2005. The 566 questionnaires were responded, and 6 unusable questionnaires were excluded, then 560 were used for the final analysis (response rate: 97.4%). For the statistical analysis, SPSS (12.0) was used to conduct the descriptive analysis, factor analysis reliability analysis, and multiple regression analysis. The results of this study were as follows: First 254 respondants (47.3%) did not know that their foodservice operation was managed by contract foodservice company, and 374 students (66.8%) did not know the name of the contract foodservice company which runned their foodservice operation. Second, the food factor of university foodservice quality had a significant positive effect on intent to revisit (P<0.001), and the food factor of university foodservice quality also had a significant positive effect on Intent to recommend (p<0.001). It was concluded that as the food factor of university foodservice qualify Increased, the intent to revisit and the intent to recommend the university foodservice increased. So when university foodservice managers plan the foodservice operation strategy, they should focus on increasing the perception of customers' foodservice quality and also advertising contract foodservice company's brand name.

• Journal of Chest Surgery
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• v.35 no.6
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• pp.439-448
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• 2002

Pulmonary artery banding (PAB) in the functional univentricular heart (UVH) is a palliative procedure for staging toward the Fontan procedure; however, it is known to be a risk factor. Material and method： The records of all 37 patients with functional UVHs who underwent surgical palliation using PAB between September 1989 and August 1999 were reviewed retrospectively. We investigated the aortic arch obstruction, the development and progression of subaortic stenosis after PAB, and risk factor of mortality according to surgical method. Result： In 37 neonates and infants with single ventricular physiology, aortic arch obstruction was combined in 7. There were 6 early deaths (16.2%) after PAB and 3 late deaths (8.1%) after Fontan operation. The actuarial overall survival including early mortality at 3 and 5 years were 80.7$\pm$6.6%, 72.2$\pm$8.2% respectively. Among 31 patients who survived PAB, 27 patients (87.1 %) could become candidates for Fontan operation； 22 patients (71.0%) completed Fontan operation with 3 deaths and 5 were waiting bidirectional cavopulmonary shunt(BCPS) or Fontan operation (follow-up mean 4.5 year, minimal 2 year). Subaortic stenosis developed in 8 patients after PAB (8/29, 27.6%)； 3 cases in the patients without arch anomaly (3/22, 13.6%) and 5 in those with arch anomaly (5/7, 71.4%). The subaortic stenosis was managed with Damus-Kaye-Stansel procedure (DKS) in 6 patients without operative mortality and conal septum resection in 2 without long-term survivor. Analysis of risk factors established that aortic arch obstruction was strongly associated with subaortic stenosis (p＜0.001). The only risk factor of late mortality was Fontan procedure without staged palliation by BCPS (p=0.001). Conclusion： PAB is effective as an initial palliative step in functional UVH. And the high risk group of patients with aortic obstruction can undergo effective short-term PAB as an initial palliative step, with subsequent DKS for subaortic stenosis. This strategy, initial PAB and careful surveillance, and early relief of subaortic stenosis can maintain acceptable anatomy and hemodynamics for later Fontan procedures.

• Korea Science and Art Forum
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• v.23
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• pp.111-122
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• 2016

The purpose of this multi-disciplinary convergent study is to establish Image Copyright Archive Model for Museums to protect image copyright and vitalize the use of images out of necessity of research and development on copyright services over the life cycle of art contents created by the museums and out of the necessity to vitalize distribution market of image copyright contents in creative industry and to formulate management system of copyright services. This study made various suggestions for enhancement of transparency and efficiency of art contents ecosystem through vitalization of use and recycling of image copyright materials by proposing standard system for calculation, distribution, settlement and monitoring of copyright royalty of 1,000 domestic museums, galleries and exhibit halls. First, this study proposed contents and structure design of image copyright archive model and, by proposing art contents distribution service platform for prototype simulation, execution simulation and model operation simulation, established art contents copyright royalty process model. As billing system and technological development for image contents are still in incipient stage, this study used the existing contents billing framework as basic model for the development of billing technology for distribution of museum collections and artworks and automatic division and calculation engine for copyright royalty. Ultimately, study suggested image copyright archive model which can be used by artists, curators and distributors. In business strategy, study suggested niche market penetration of museum image copyright archive model. In sales expansion strategy, study established a business model in which effective process of image transaction can be conducted in the form of B2B, B2G, B2C and C2B through flexible connection of museum archive system and controllable management of image copyright materials can be possible. This study is expected to minimize disputes between copyright holder of artwork images and their owners and enhance manageability of copyrighted artworks through prevention of such disputes and provision of information on distribution and utilization of art contents (of collections and new creations) owned by the museums. In addition, by providing a guideline for archives of collections of museums and new creations, this study is expected to increase registration of image copyright and to make various convergent businesses possible such as billing, division and settlement of copyright royalty for image copyright distribution service.

• Journal of Intelligence and Information Systems
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• v.20 no.1
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• pp.149-161
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• 2014

The export of domestic public services to overseas markets contains many potential obstacles, stemming from different export procedures, the target services, and socio-economic environments. In order to alleviate these problems, the business incubation platform as an open business ecosystem can be a powerful instrument to support the decisions taken by participants and stakeholders. In this paper, we propose an ontology model and its implementation processes for the business incubation platform with an open and pervasive architecture to support public service exports. For the conceptual model of platform ontology, export case studies are used for requirements analysis. The conceptual model shows the basic structure, with vocabulary and its meaning, the relationship between ontologies, and key attributes. For the implementation and test of the ontology model, the logical structure is edited using Prot$\acute{e}$g$\acute{e}$ editor. The core engine of the business incubation platform is the simulator module, where the various contexts of export businesses should be captured, defined, and shared with other modules through ontologies. It is well-known that an ontology, with which concepts and their relationships are represented using a shared vocabulary, is an efficient and effective tool for organizing meta-information to develop structural frameworks in a particular domain. The proposed model consists of five ontologies derived from a requirements survey of major stakeholders and their operational scenarios: service, requirements, environment, enterprise, and county. The service ontology contains several components that can find and categorize public services through a case analysis of the public service export. Key attributes of the service ontology are composed of categories including objective, requirements, activity, and service. The objective category, which has sub-attributes including operational body (organization) and user, acts as a reference to search and classify public services. The requirements category relates to the functional needs at a particular phase of system (service) design or operation. Sub-attributes of requirements are user, application, platform, architecture, and social overhead. The activity category represents business processes during the operation and maintenance phase. The activity category also has sub-attributes including facility, software, and project unit. The service category, with sub-attributes such as target, time, and place, acts as a reference to sort and classify the public services. The requirements ontology is derived from the basic and common components of public services and target countries. The key attributes of the requirements ontology are business, technology, and constraints. Business requirements represent the needs of processes and activities for public service export; technology represents the technological requirements for the operation of public services; and constraints represent the business law, regulations, or cultural characteristics of the target country. The environment ontology is derived from case studies of target countries for public service operation. Key attributes of the environment ontology are user, requirements, and activity. A user includes stakeholders in public services, from citizens to operators and managers; the requirements attribute represents the managerial and physical needs during operation; the activity attribute represents business processes in detail. The enterprise ontology is introduced from a previous study, and its attributes are activity, organization, strategy, marketing, and time. The country ontology is derived from the demographic and geopolitical analysis of the target country, and its key attributes are economy, social infrastructure, law, regulation, customs, population, location, and development strategies. The priority list for target services for a certain country and/or the priority list for target countries for a certain public services are generated by a matching algorithm. These lists are used as input seeds to simulate the consortium partners, and government's policies and programs. In the simulation, the environmental differences between Korea and the target country can be customized through a gap analysis and work-flow optimization process. When the process gap between Korea and the target country is too large for a single corporation to cover, a consortium is considered an alternative choice, and various alternatives are derived from the capability index of enterprises. For financial packages, a mix of various foreign aid funds can be simulated during this stage. It is expected that the proposed ontology model and the business incubation platform can be used by various participants in the public service export market. It could be especially beneficial to small and medium businesses that have relatively fewer resources and experience with public service export. We also expect that the open and pervasive service architecture in a digital business ecosystem will help stakeholders find new opportunities through information sharing and collaboration on business processes.