• Journal of Korean Society for Quality Management
• /
• v.49 no.3
• /
• pp.255-268
• /
• 2021

Purpose: We sought to understand why a high-speed rotating projectile featuring a fuze-and-body assembly sometimes exhibited airburst, and we intended to improve the flight stability by eliminating airburst. Methods: We performed characteristic factor analysis, structural mechanics modeling, and dynamic modeling and simulation; and we scheduled firing tests to discover the cause of airburst. We used a step-by-step procedure to analyze the reliability function for selecting the bonding force standard that prevents airburst. Results: The 00MM high-speed rotating projectile features a fuze bonded to a body assembly; the bonding sometimes can break on firing. The resulting contact force, vibration and roll damping during flight generated yaw. Flight became unstable; fuze operation triggered an airburst. Our reliability test improved the bonding force standard (the force was increased). When the bonding force was at least the minimum required, a firing test revealed that airburst/flight instability disappeared. Conclusion: Analysis and identification of the causes of flight instability and airburst render military training safer and enhance combat power. Ammunition must perform as designed. Our method can be used to set standards that improve the performances of similar types of ammunition.

• The Journal of the Korea Contents Association
• /
• v.11 no.1
• /
• pp.236-244
• /
• 2011

Recently, the number of interventional procedures has increased dramatically as an alternative of invasive surgical procedure. The need for the quality control program of the angiographic units has also increased, because of concerns about the increased patient dose and the importance of image quality of angiographic units for the successful procedures. The purpose of this study was to propose an optimal guideline for the quality control program of the angiographic units. We reviewed domestic and international standards about medical imaging system and we evaluated the quality of 61 angiographic units in Korea with the use of NEMA 21 phantom. According to the results of our study, we propose a guideline for the quality control program of the angiographic units. Quality control program includes tube voltage test, tube current test, HVL test, image-field geometry test, spatial resolution test, low-contrast iodine detectability test, wire resolution test, phantom entrance dose test. Proposed reference levels are as follows: PAE < $\pm$ 10% in tube voltage test, PAE < $\pm$ 15% in tube current test, minimum 2.3 mmAl at 80 kVp in HVL test, minimum 'acceptable' level at image-field geometry test, 0.8 lp/mm for detector size of 34-40cm, 1.0 lp/mm for detector size of 28-33cm, 1.2 lp/mm for detector size of 22-27cm in spatial resolution test, minimum 200mg/cc in low contrast iodine detectability test, phantom entrance dose should be under 10R/min, 0.012 inch wire should be seen at static wire resolution test, and 0.022 inch wire should be seen at moving wire resolution test.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.54 no.3
• /
• pp.251-260
• /
• 2021

As the aging population of the world grows, senior-friendly foods are becoming increasingly popular. In this study, the quality characteristics of domestic commercial senior-friendly foods were investigated and compared to the standard specifications of the Food Code and KS H4897. Herein, 18 samples of domestic commercial senior-friendly foods were utilized to analyze their appearance, physical properties (hardness and viscosity), nutritional value (protein, vitamin, mineral and dietary fiber), digestion rate, and hygiene indicator bacteria. When compared to the hardness standards of the Food Code all 18 samples were found to be satisfactory; however, when compared to the nutritional standard (at least three types of nutrients must be above the minimum), only five products, HG-7, DW-1, PS-1, OH-1 and OH-2, were found to be satisfactory. In addition, when the 18 samples were compared to the Korean Industrial Standard (2020), all 18 products were found to be satisfactory for physical properties and hygiene standards; furthermore, all samples, excluding HB-2, were suitable for nutritional standards (at least one type of nutrient must be above the standard).

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.10
• /
• pp.88-96
• /
• 2017

The construction standards in Korea consist of design standards and specifications. They are provided by the national transportation electronic information center in file format, not in a DB, which may lead to their incomplete utilization and versatility, such as a lack of history management and reference functions. This also makes it difficult to cross-refer to standards and manage revision history. In this study, we developed a code management system for the national construction standards by analyzing domestic and overseas related systems, in order to pinpoint the problems in the current system and its development direction and, thus, to suggest a detailed plan for the design and implementation of a code management system. The developed system comprises four subsystems, namely a construction standards making system, construction standards service system, construction standards maintenance system and construction standards portal system. The results of this study are expected to improve the user's convenience by facilitating the revision, operation and history management of the complex and various construction standards, and to provide high-quality national construction standards by effectively supporting the revision and operation of the national construction standards with minimum duplication and conflicts.

• Journal of Environmental Impact Assessment
• /
• v.2 no.2
• /
• pp.73-83
• /
• 1993

Increasing concern for the environment in Korea has led to the demand that major policies and large-scale development projects be subjected to detailed impact assessment. This paper reports on the state of data related to the prediction of the environmental impact (EIA) to emphasize the importance of data quality. Environmental impact statements (EIS) consulted with the Ministry of Environment of Korea were analyzed from 1981 through 1992. Many of assessors used existing data and collected supplementary data from field survey. Most of the results of EIA are presented directly or summarized on maps and as graphics. For the national purpose, large source of quality-controlled data such as atmospheric data have been developed, However, there are the deficiency in data to analyze the impact of human activity, and data gaps and incompatibilities among systems. Consequently, the development of data bank systems including computer database and remotely-sensed satellite data is required to improve the quality of data which are relevant to EIA. The data bank system should be organized meaningfully in minimum time with a least cost, and measurement standards must be made explicit. Geographical information systems (GIS) are applicable to the graphic presentation or to the impact prediction model.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
• /
• v.5 no.3
• /
• pp.110-116
• /
• 2012

As rapid development of the Internet, there are increasing interests about quality of service of VoIP using the Internet network and established PSTN. There was some study going on to improve the quality of service from the point of view of supplier's mainly. However recently, the demand for setting up the objective standards that service provider can offer to customers is needed as the interests from customers has been going up. In this study, we analysed the results from the test using PESQ which is a parameter of quality of service. we offer the conditions of network which guarantees the minimum quality of phone call using VoIP.

• Management & Information Systems Review
• /
• v.29 no.4
• /
• pp.225-244
• /
• 2010

In the information society, characterized by knowledge and network economy, standards and standardization became a very important factor in determining the competitiveness of nations and firms. This paper defines the concept of standards and standardization and reconstructs the theory on the relationship between standards and technological innovation. The findings and policy implications are as follows. First, the effect of standards on technological innovation differs according to its function(compatibility, minimum quality, information, and variety reduction) and types(product-related and non-product). On the other hand, standards can impede technological innovation. Second, in terms of national innovation system(NIS), standards are an infra-technology, which is a public good. Therefore, government should decide the optimal level of investment on standards and standardization. Third, since standards foster firms' innovation over the all stages of business activities company, industry, and government should connect standardization activities with R&D, manufacturing, marketing, supply chain, and technology transfer, Fourth, standards play an important role in product innovation as well as process innovation. Based on these theoretical background and hypotheses, the empirical study of the Korean firms is needed.

• Journal of Korea Multimedia Society
• /
• v.9 no.7
• /
• pp.864-871
• /
• 2006

With the advancement of the digital broadcasting and popularity of Internet, there is an increasing demand for digital data. Recently, several studies have been made on the digital watermarking for copyright protection of digital data. We propose a blind video watermarking using minimum modification of motion vectors. Conventional methods based on motion vectors do watermarking using modification of motion vectors. However, change of motion vectors results in the degradation of video quality. Thus, our proposed algorithm minimizes modification of the original motion vectors to avoid degradation of video quality using simple embedded conditions. Besides, our scheme guarantees the amount of embedded watermark data using the adaptive threshold considering the human visual characteristic. In addition, this is compatible with current video compression standards without changing the bitstream. Experimental result shows that the proposed scheme obtains better video quality than other previous algorithms by about $0.5{\sim}1.0\;dB$.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.6C
• /
• pp.497-504
• /
• 2005

We propose an efficient video watermarking scheme using re-estimation and minimum modification technique of motion vectors. Conventional methods based on motion vectors do watermarking using modification of motion vectors. However, change of motion vectors results in the degradation of video quality. Thus, our scheme minimizes the modification of the original motion vectors and replaces an original motion vector by the adjacent optimal motion vector using re-estimation of motion vectors to avoid degradation of video quality. Besides, our scheme guarantees the amount of embedded watermark data using the adaptive threshold considering for an efficient video watermarking. In addition, this is compatible with current video compression standards without changing the bitstream. Experimental result shows that the proposed scheme obtains better video quality than other previous algorithms by about $0.6{\sim}1.3\;dB$.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.1C
• /
• pp.78-85
• /
• 2007

With the advancement of the digital broadcasting and popularity of the Internet, recently, many studies are making on the digital watermarking for the copyright protection of digital data. This paper proposes the minimum modification method of motion vector to minimize the degradation of video quality, hiding subtitles of many language and information of OST(original sound track), character profiles, etc. as well as the copyright protection. Our proposed algorithm extracts feature vector by comparing motion vector data with watermark data, and minimize the modification of motion vectors by deciding the inversion of bit. Thus the degradation of video quality is minimized comparing to conventional algorithms. This algorithm also can check data integrity, and retrieve embedded hidden data simply and blindly. And our proposed scheme can be useful for conventional MPEG-1, -2 standards without any increment of bit rate in the compressed video domain. The experimental result shows that the proposed scheme obtains better video quality than other previous algorithms by about $0.5{\sim}1.5dB$.