• Journal of the Korean Society of Mineral and Energy Resources Engineers
• /
• v.55 no.6
• /
• pp.614-623
• /
• 2018

The recent occurrence of consecutive large earthquakes in the southeastern part of the Korean peninsula has brought significant attention to the prevention of earthquake damage in Korea. This article aims to explore a technology-based approach for earthquake drills using state-of-the-art visual intelligence and virtual reality technologies. The technical process consists of several stages, including acquisition of image information in living spaces using a camera, recognition of objects from the acquired image information, extraction of three dimensional geometric information, simulation of virtual earthquakes using dynamic modelling techniques such as the discrete element method, and realization of the simulated earthquake in a virtual reality environment. This article provides a comprehensive analysis of the individual processes at each stage of the technical process, a survey on the current status of related technologies, and discussion of the technical challenges in its execution.

• Nuclear Engineering and Technology
• /
• v.56 no.1
• /
• pp.167-179
• /
• 2024

This study explores the feasibility of employing (U, Th)-based accident tolerant fuels (ATFs), specifically (_0.8UO₂, _0.2ThO₂), (_0.8UN, _0.2ThN), and (_0.8UC, _0.2ThC). The investigation assesses the overall performance of these proposed fuel materials in comparison to the conventional UO₂, focusing on deep neutronic and thermal-hydraulic (Th) analyses. Neutronic analysis utilized the MCNPX code, while COMSOL Multiphysics was employed for thermal-hydraulic analysis. The primary objective of this research is to overcome the limitations associated with traditional UO₂ fuel by exploring alternative fuel materials that offer advantages in terms of abundance and potential improvements in performance and safety. Given the limited abundance of UO₂, long-term sustainable nuclear energy production faces challenges. From a neutronic standpoint, the U-Th based fuels demonstrated remarkable fuel cycle lengths, except (_0.8UN, _0.2ThN), which exhibited the minimum fuel cycle length and, consequently, the lowest fuel burn-up. Regarding thermal-hydraulic performance, (_0.8UN, _0.2ThN) exhibited outstanding performance with significant margins against fuel melting compared to the other materials. Overall, when considering the integrated performance, the most favourable results were obtained with the use of the (_0.8UC, _0.2ThC) fuel configurations. This study contributes valuable insights into the potential benefits of (U, Th)-based ATFs as a promising avenue for enhanced nuclear fuel performance.

• 대한공업교육학회지
• /
• v.34 no.2
• /
• pp.379-395
• /
• 2009

In Nepal, unemployment and underemployment rate is very high among the youth between 15-24 ages. Generally people tend to discourage acquisition of skills for a career. Access to skill training is limited, especially for the poor, women, and disadvantaged, and the quality of skills training is variable and often not linked to market needs. Strengthening the technical education and vocational training (TEVT) sector to deliver more relevant and market oriented training is essential. To improve the country's pool of technical skilled manpower and unemployment problem, the government has attempted various programs in the last two decades to institutionalize technical education and vocational training. These had initially mixed results mainly due to poor organization and management of the TEVT sector, lack of proper linkage between the training programs and the needs of the labor market, lack of proper equipment and instructional materials and inadequately trained instructors. Council for Technical Education and Vocational Training (CTEVT) as a leading organization in TEVT sector of Nepal should focus on community-based vocational trainings for the purpose of reducing poverty in grassroots level addressing excluded and marginalized groups. It is a big challenge as well as opportunity for CTEVT and TEVT professionals.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2008.10a
• /
• pp.448-451
• /
• 2008

Magnesium alloys still have a lot of technical challenges to be solved for more applications. There have been many research activities to enhance formability of magnesium alloys. One is to design new alloy composition having better formability. Also, low formability of wrought alloys can be improved by optimizing the processing variables. In the present study, effect of process variables such as forging temperature and forging speed were investigated to forgeability of three different magnesium alloys such as AZ31, AZ61 and ZK60. To understand the effect of process variables more specifically, both numerical and experimental works have been carried out on the model which contains both upsetting and extrusion geometries. Forgeability of magnesium alloys was found to depend more on the forging speed rather than temperature. Forged sample showed a significant activity of twinning, which was found to be closely related with flow uniformity.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.9
• /
• pp.1935-1940
• /
• 2009

One of the key technical challenges of wireless sensor network (WSN) is location management of sensor nodes. Typical node location management methods use GPS, ultrasonic sensors or RSSI. In this paper we propose a new location management method which adopts regression analysis of RSSI measurement to improve the accuracy of sensor node position estimation. We also evaluated the performance of proposed method by comparing the experimental results with existing scheme. According to the results, our proposed method, LM-RAR, shows better accuracy than existing location management scheme using RSSI and Friis' equation.

• Journal of Internet Computing and Services
• /
• v.17 no.5
• /
• pp.67-74
• /
• 2016

Distributed agile software development faces difficulties for instance lack of visibility across development and delivery processes, complex and disjointed development processes, inability to capitalize on business opportunities, lack of communication agility between disconnected owners, development teams, and users or clients. However these difficulties are solved with the help of cloud computing services. This study proposes a framework to provide a skeletal or structural environment for distributed agile software development in cloud computing environment. The framework guide towards the best tooling to deliver a consistent, automated, governed, and unified agile software development process with reduced technical debt, and minimized project backlog. In addition to this, the study highlights the benefits of cloud computing in agile software development.

• 유체기계공업학회:학술대회논문집
• /
• 2002.12a
• /
• pp.477-481
• /
• 2002

This paper reports on the development of micro power system component under way at Seoul National University. The need of micro power system is explained and components of micro power system are described. The developments of hydrogen-air micro combustor, micro igniter based poly-silicon heater and micro thruster are described. To manufacture 3-D micro structure the process that manufactures high aspect ratio structures has been developed and optimized. Design, fabrication, and experiment processes are introduced and technical challenges in each phase are described.

• Journal of Advanced Marine Engineering and Technology
• /
• v.37 no.3
• /
• pp.274-281
• /
• 2013

The variable demand on the energy market requires a great flexibility in operating hydro turbines. However, Francis turbine operated at off-design conditions poses technical challenges related to large unsteady forces given by residual swirl and angular momentum. In order to improve the performance of a Francis turbine, the paper presents a numerical investigation of the 3D flow in the turbine at off-design conditions and discusses the influence of variable guide vane openings on the internal flow of a Francis turbine with the help of computational fluid dynamics. First, the internal flow characteristics of Francis turbine operated by varied guide vane angle at off design condition are computed and the optimal guide vane angle is obtained. Secondly, the Francis turbine is operated with guide vane number varies at the optimal guide vane angle. Finally, pressure contours and velocity distributions in the distributor are discussed and compared.

• Archives of Plastic Surgery
• /
• v.47 no.5
• /
• pp.382-391
• /
• 2020

Facial palsy has a broad clinical presentation and the effects on psychosocial interaction and facial functions can be devastating. Pediatric facial palsy, in particular, introduces unique familial and technical considerations as anatomy, future growth potential, and patient participation influence treatment planning. Though some etiologies of pediatric facial palsy are self-limiting, congenital and long-standing facial palsies pose difficult challenges that require a combination of surgical, adjunctive, and rehabilitative techniques to achieve facial reanimation. Given the spectrum of ages and symptom severity, as well as the various surgical options available for facial palsy, a tailored approach needs to be developed for each child to restore facial balance and function. Here, we review the etiologies, workup, and treatment of pediatric facial palsy and present our novel algorithmic approach to treatment.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1517_1518
• /
• 2009

Interest has grown recently in the concept of "unconventional nanofabrication", the creation of nanoscale features by methods that avoid the technical hurdles and high cost of nano-lithographic processes. One of the challenges has been to reliably and inexpensively produce channels of nanometer dimension, as small as 60 nm, in the materials commonly used for soft lithography. In this manuscript, we present new approaches based on simple concepts of wrinkle and buckling patterns.