• International Journal of Aeronautical and Space Sciences
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• 제14권3호
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• pp.215-221
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• 2013

The basic quantitative tool for the study of hypersonic rarefied flows is the direct simulation Monte Carlo method (DSMC). The DSMC method requires a large amount of computer memory and performance and is unreasonably expensive at the first stage of spacecraft design and trajectory analysis. A possible solution to this problem is approximate engineering methods. However, the Monte Carlo method remains the most reliable approach to compare to the engineering methods that provide good results for the global aerodynamic coefficients of various geometry designs. This paper presents the calculation results of aerodynamic characteristics for spacecraft vehicles in the free molecular, the transitional and the continuum regimes using the local engineering method. Results and methods would be useful to calculate aerodynamics for new-generation hypersonic vehicle designs.

• Journal of Electrochemical Science and Technology
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• 제15권1호
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• pp.111-131
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• 2024

Lignin-derived porous carbon has been identified as a versatile electrode material for supercapacitors (SCs) in energy storage systems (ESSs) owing to their intrinsic advantages including good electrical conductivity, low cost, high thermal and chemical stability, and high porosity, which stem from high surface, appropriate pore distribution, tailored morphologies, heterostructures, and diverse derivates. In this review, to provide a fundamental understanding of the properties of lignin, we first summarize the origin, historical development, and basic physicochemical properties. Next, we describe essential strategies for the preparation of lignin-derived porous carbon electrode materials and then highlight the latest advances in the utilization of lignin-derived porous carbon materials as advanced electrode materials. Finally, we provide some of our own insights into the major challenges and prospective research directions of lignin-derived porous carbon materials for supercapacitors. We believe that this review will provide general guidance for the design of next-generation electrode materials for supercapacitors.

• The Journal of the Convergence on Culture Technology
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• 제7권1호
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• pp.469-486
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• 2021

Vietnam is a country where the largest number of Korean companies have branched out, and calibers who can speak Vietnamese are on great demands. In the multicultural classroom, students of Vietnamese background occupy the first or second largest composition among students with multicultural backgrounds; therefore, if teachers can teach in Vietnamese, the positive effects can be promising. This study presents and evaluates a Vietnamese language class developed and operated for the first time in Korea by a university to raise prospective teachers' global-multicultural competences. Two series of the classes were conducted during two vacations of 2018, and 20 students participated. As a results, the groups showed a significant increase in the global-multicultural competences; About 95 percent of the participants demonstrated improvement in the competences. The participants stated opinions: the classes should expand to offer opportunities for many other students who may want to acquire Vietnamese; the participants had better understandings of the Vietnamese cultures, envisioned their role as a Vietnamese speaker and suggested extended opportunities for contacts with Vietnamese cultures. The study hopes that other universities apply the educational model and the case study and that, as a result, teachers can contribute to building harmonious Korean-Vietnamese relations using Vietnamese.

• The Journal of Asian Finance, Economics and Business
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• 제3권2호
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• pp.51-57
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• 2016

The aim of this study is to examine of the cluster approach to ensure high rates of innovation, information and communication enterprises of information technology cluster in order to enhance the competitiveness of regions. Keeping with the previous literature, the present research determined that the novelty of the problem, concerning of the creation IT clusters as drivers of new generation, i.e. a kind of platform of "startup accelerators" through the creation of previously not existing in the country high-tech industries and sectors of the economy. The study employs system approach involves to determine prospective directions of the formation of clusters of IT industry, also applies structured approach to shows relationships between elements of cluster systems (participants of cluster), as well as focusing on some aspects of cluster development such as networking. Based on this analysis we have proposed to create clusters in regions, which can play the role of translator's innovations at the periphery of the country. This research shows that formation of IT clusters is one of the most successful tools to avoid of dependence of Kazakhstan from raw materials.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 한국방송공학회 1998년도 Proceedings of International Workshop on Advanced Image Technology
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• pp.29-33
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• 1998

In this paper, we propose a hierarchical segmentation method for tracking a semantic video object using a watershed algorithm based on morphological filtering. In the proposed method, each hierarchy consists of three steps: First, markers are extracted on the simplified current frame. Second, region growing by a modified watershed algorithm is performed for segmentation. Finally, the segmented regions are classified into 3 categories, i.e., inside, outside, and uncertain regions according to region probability values, which are acquired by the probability map calculated from a estimated motion field. Then, for the remaining uncertain regions, the above three steps are repeated at lower hierarchies with less simplified frames until every region is decided to a certain region. The proposed algorithm provides prospective results in video sequences such as Miss America, Clair, and Akiyo.

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.4885-4890
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• 2015

Background: Helicobacter pylori plays an important role in gastric cancer and typical eradication regimens are no longer effective in many countries, including Thailand. The aim of our study was to compare the effect of Lactobacillus delbrueckii and Streptococcus thermophillus on tailored triple therapy for Helicobacter pylori eradication. Materials and Methods: This prospective single-center study was conducted in Thailand. Helicobacter pylori associated gastritis patients were randomized to 2 groups: group 1 (n=100) was tailored triple therapy with placebo (esomeprazole 20 mg bid, clarithromycin 500 mg bid or metronidazole 400 mg tid if clarithromycin resistance and amoxicillin 1000 mg bid), and group 2 was tailored triple therapy plus pretreatment with probiotic containing yogurt. Successful eradication was defined as both negative histology and negative rapid urease test at four weeks after treatment. Results: A total of 200 infected patients were enrolled. PP analysis involved 194 patients: 96 in the tailored triple therapy with placebo group (group 1) and 98 the in tailored triple therapy plus pretreatment with probiotic containing yogurt group (group 2). Successful eradication was observed in 170 (87.6%) patients; by PP analysis, the eradication rate was significantly higher in group 2 (P = 0.04, 95%CI; 0.02-0.13) than in group 1. ITT analysis also showed that the value was significantly higher in the tailored triple threapy plus pretreatment with probiotic containing yogurt group (group 2) (89/100; 89%) than in the tailored triple therapy with placebo group (group 1) (P= 0.01, 95%CI; 0.04-0.15). In terms of adverse events, there was no significant difference between the two groups. Conclusions: Pretreatment with probiotic containing yogurt can improve Helicobacter pylori eradication rates with tailored triple therapy. Adding probiotics does not reduce adverse effects of the medication.

• Journal of Korea Spatial Information System Society
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• 제9권3호
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• pp.81-89
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• 2007

We analyzed the technology portfolio matrix for the car navigation technology using QFD method and accordingly suggested the navigation technology development direction. QFD is a useful tool to analyze the customer demands and the technologies. Depending on the survey results from the latent customers and the technology capabilities from the study of the national institutions, we suggested technology portfolio matrix. The visual HMI technology, safe driving support technology, and the navigator information management technology are the most prospective area for R&D investment according to the portfolio matrix.

• Korean Journal of Materials Research
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• 제26권2호
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• pp.100-108
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• 2016

Zinc Sulfide (ZnS) is one of the II-VI semiconducting materials, having novel fundamental properties and diverse areas of application such as light-emitting diodes (LEDs), electroluminescence, flat panel displays, infrared windows, catalyst, chemical sensors, biosensors, lasers and biodevices, etc. However, despite the remarkable versatility and prospective potential of ZnS, research and development (R&D) into its applications has not been performed in much detail relative to research into other inorganic semiconductors. In this study, based on global patent information, we analyzed recent technical trends and the current status of R&D into ZnS applications. Furthermore, we provided new technical insight into ZnS applicable fields using in-depth analysis. Especially, this report suggests that ZnS, due to its infrared-transmitting optical property, is a promising material in astronomy and military fields for lenses of infrared systems. The patent information analysis in this report will be utilized in the process of identifying the current positioning of technology and the direction of future R&D.

• Journal of the military operations research society of Korea
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• 제22권2호
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• pp.37-48
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• 1996

This paper analyzes the state of the art on the non-lethal disabling technologies(NDTs) and provides the direction for the development and use of non-lethal weapons. A dozen categories of NDTs are surveyed and explored for the prospective military operations in the future. These technologies may be mixed and matched for a specific purpose that would be potent yet safer than conventional lethal weapons. Many commonly available technologies that are either directly applicable as NDTs or with some engineering adaptation should be first considered to develope. These are NDTs for anti-mobility as follows: anti-traction technology, polymer agents and combustion alternation technology. Non-lethal weapons especially useful in our situation include destroying weapon-guidance systems, disabling engines of aircrafts and ground vehicles and C4I systems.

• Journal of Electrical Engineering and Technology
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• 제8권4호
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• pp.945-950
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• 2013

This paper deals with the ellipse permanent magnet machines for the minimization of torque ripple based on electromagnetic field theory. On the basis of a magnetic vector potential and a two dimensional (2-D) polar system, analytical solutions for flux density due to permanent magnet (PM) and current are obtained. In particular, the analytical solutions for mathematical expressions of magnets with different circumferential thicknesses can be solved introducing improved magnetization modeling techniques. The analytical results are validated extensively be nonlinear finite element solutions, a reduction of torque ripple can be achieved.