• Journal of the Korea Safety Management & Science
• /
• v.14 no.1
• /
• pp.225-233
• /
• 2012

The research discusses interrelationship of structural and reliability importance measures which used in the probabilistic safety assessment. The most frequently used component importance measures, such as Birnbaum's Importance (BI), Risk Reduction (RR), Risk Reduction Worth (RRW), RA (Risk Achievement), Risk Achievement Worth (RAW), Fussel Vesely (FV) and Critically Importance (CI) can be derived from two structure importance measures that are developed based on the size and the number of Minimal Path Set (MPS) and Minimal Cut Set (MCS). In order to show an effectiveness of importance measures which is developed in this paper, the three representative functional structures, such as series-parallel, k out of n and bridge are used to compare with Birnbaum's Importance measure. In addition, the study presents the implementation examples of Total Productive Maintenance (TPM) metrics and alternating renewal process models with exponential distribution to calculate the availability and unavailability of component facility for improving system performances. System state structure functions in terms of component states can be converted into the system availability (unavailability) functions by substituting the component reliabilities (unavailabilities) for the component states. The applicable examples are presented in order to help the understanding of practitioners.

• The KIPS Transactions:PartD
• /
• v.8D no.6
• /
• pp.637-644
• /
• 2001

EJB, providing specification for development and deployment of component based application, permits distributed development as central element of J2EE environment that manages automatically transaction management, persistence, concurrency control that are the most complicated work in enterprise environment. In this paper, we wish to resolve DAO's transaction logic complexity and performance reduction of system in the EJB based legacy system. Therefore, this paper describes the design and implementation of IDAO that applies Iterator pattern. IDAO gets effect that reduces complexity of transaction logic, system overload by database connection, and reduction of performance through container managed transaction.

• Korean Journal of Remote Sensing
• /
• v.34 no.6_1
• /
• pp.1009-1024
• /
• 2018

With the increased use of LiDAR (Light Detection and Ranging) that can obtain over millions of point dataset, methodologies for efficient search and dimensionality reduction for the point cloud became a crucial technique. The existing octree-based "parametric algorithm" has proved its efficiency and contributed as a part of PCL (Point Cloud Library). However, the implementation of the algorithm on GPU (Graphics Processing Unit) is considered very difficult because of structural constraints of the octree implemented in PCL. In this paper, we present a method for the parametric algorithm on GPU environment and implement a projection of the queried points on four directions with an improved noise reduction.

• Korean Journal of Materials Research
• /
• v.31 no.12
• /
• pp.719-726
• /
• 2021

Through the process of chemical vapor deposition, Tungsten Hexafluoride (WF₆) is widely used by the semiconductor industry to form tungsten films. Tungsten Hexafluoride (WF₆) is produced through manufacturing processes such as pulverization, wet smelting, calcination and reduction of tungsten ores. The manufacturing process of Tungsten Hexafluoride (WF₆) is required thorough quality control to improve productivity. In this paper, a real-time detection system for oxidation defects that occur in the manufacturing process of Tungsten Hexafluoride (WF₆) is proposed. The proposed system is implemented by applying YOLOv5 based on Convolutional Neural Network (CNN); it is expected to enable more stable management than existing management, which relies on skilled workers. The implementation method of the proposed system and the results of performance comparison are presented to prove the feasibility of the method for improving the efficiency of the WF₆ manufacturing process in this paper. The proposed system applying YOLOv5s, which is the most suitable material in the actual production environment, demonstrates high accuracy (mAP@0.5 99.4 %) and real-time detection speed (FPS 46).

• Korea Trade Review
• /
• v.47 no.1
• /
• pp.115-130
• /
• 2022

In this study, I focus on analyzing how the effects of implementing ETS are different depending on whether Korean ETS linking with carbon markets in other countries. The global computable general equilibrium (CGE) model built in this study analyzes the chages in the production and trade of industrial sectors according to the international linkage of ETS compared to the reference scenario of emissions reduction targets and implementation of ETS. From the analysis of internatioanl linkage of carbon markets scenarios, Annex B countries-South Korea carbon market linkage with individual ETS in China worse the economic outcomes in South Korea the most. This means South Korea lose the international competitiveness compared to China in this scenario. On the other hand, Annex B-China carbon market linkage with Korean individual ETS implementation reduce the decreases in production and trading. The most effective way is to join a global emissions trading market with China. The results are consistent in most industries of South Korea. These results are caused by that the supply of emission allowance is increased and the price of emissions allowances is dropped by China's participation to the carbon market, which can be understood to reduce the carbon reduction cost for industrial sectors. In addition, it can be also concluded that the determinant of the negative impact of ETS on changes in production and trade is more sensitive to the price of emissions allowances than to the characteristics of production and trade structure.

• Journal of the Korean Institute of Telematics and Electronics C
• /
• v.36C no.6
• /
• pp.37-43
• /
• 1999

Two-way addressing method has been proposed for efficient VLSI implementation of Euclidean calculation circuit for pipelined Reed-Solomon decoder. This new circuit is operating with single clock while exploiting maximum parallelism, and uses register addressing instead of register shifting to minimize the switching power. Logic synthesis shows the circuit with the new scheme takes 3,000 logic gates, which is about 40% reduction from the previous 5,000 gate implementation. Computer simulation also shows the power consumption is about 3mW. The previous implementation with multiple clock consumed about 5mW.

• Journal of Korean Neurosurgical Society
• /
• v.51 no.6
• /
• pp.338-342
• /
• 2012

Objective : The aim of this study is to implement a critical pathway (CP) for patients undergoing lumbar laminectomy or microdiscectomy and describe the results before and after the CP in terms of length of hospital stay and cost. Methods : From March 2008 to February 2009, 61 patients underwent lumbar laminectomy or microdiscectomy due to stenosis or one- or two-level disc herniation in our department and were included in the prepathway group. After development and implementation of the CP in March 2009, 58 patients were applicable for the CP, and these were classified as the postpathway group. Results : The CP, which established a 6-day hospital stay (5 bed-days), was fulfilled by 42 patients (72.4%) in the postpathway group. The mean length of stay was 5.4 days in the postpathway group compared to 6.9 days in the prepathway group, demonstrating a 20% reduction, which was a statistically significant difference ($p{\leq}0.000$). There was a statistically significant reduction in charges for bed and nursing care (p=0.002). Conclusion : Implementation of a CP for lumbar laminectomy or microdiscectomy produced significant decreases in length of hospitalization and charges for bed and nursing care. We believe that this CP reduces the unnecessary use of hospital resources without increasing risk of adverse events.

• The Journal of the Korea Contents Association
• /
• v.18 no.7
• /
• pp.527-535
• /
• 2018

This study examines how the implementation of the Normalization policy of public institutions aimed at reducing debt affects accounting conservatism in public corporations. In particular, we analyze the general behavior of accounting conservatism based on debt ratio, and analyze whether the policy has changed this behavior of conservatism. Empirical findings are summarized as following. We show that debt ratios are positively associated with conservatism, consistent with the result for the private corporations. This result means that public corporations increase their conservatism as their debt ratios increase. However, no significant effect is found in this relationship after the implementation of the policy. This finding implies that the implementation of Normalization policy is not a factor that alters the conservative accounting practices of public corporations. This suggests that the recent debt reduction performance of public corporations is irrelevant to conservatism and is the result of the actual process of normalization of management. The results documented in this paper provide an important empirical evidence for evaluating the performance of the government policy at the present time when the debt reduction policy of public institutions is viewed more important than ever.

• Asia pacific journal of information systems
• /
• v.9 no.3
• /
• pp.159-175
• /
• 1999

For the past decade, although there have been many studies which examined factors influencing the extent of EDI systems implementation, it is very hard to find out studies which directly investigated what the effectiveness of EDI systems are, and which factors contribute to the successful implementation of EDI systems. In this regard, this research aims to explore for the factors which constitute the effectiveness of EDI systems as perceived, based on a survey from 202 companies. The major steps of the current research are as follows. First, in order to identify important factors constituting the effectiveness of EDI systems, previous research related to the effectiveness of EDI systems was reviewed and analyzed. Second, individual items which can be considered as candidates to represent the effectiveness of EDI systems were derived from this previous research review, and a survey questionnaire was developed using those derived items. Based on the developed survey questionnaire, a pretest was administered at several domestic business firms with experiences of EDI systems. Third, survey questionnaires were distributed to and collected from the 202 companies which experienced EDI implementation. Accordingly, this research derived out five factors constituting the effectiveness of EDI systems from the result of a multivariate data analysis: strategic advantage, time reduction in business process, accuracy improvement, cost reduction, and improvement of business process quality. It was also interesting to find that the factors of EDI effectiveness are divided into three levels, similarly to three levels of the Anthony's hierarchical model of organization(Anthony, 1965): strategic, managerial, and operational levels. Furthermore, from the levels of derived factors, we developed a conceptual model which explains the possible causal relations of those factors in a hierarchical manner.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.4
• /
• pp.1867-1875
• /
• 2011

In this paper, a low-area 256-point FFT structure is proposed. For low-area implementation CSD(Canonic Signed Digit) multiplier method is chosen. Because multiplication type should be less for efficient CSD multiplier application to the FFT structure, the Radix-$4^2$ algorithm is chosen for those purposes. After, in the proposed structure, the number of multiplication type is minimized in each multiplication block, the CSD multipliers are applied for implementation of multiplication. Furthermore, in CSD multiplier implementation, cell-area is more reduced through common sub-expression sharing(CSS). The Verilog-HDL coding result shows 29.9% cell area reduction in the complex multiplication part and 12.54% cell area reduction in overall 256-point FFT structure comparison with those of the conventional structure.