• Nuclear Engineering and Technology
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• v.48 no.3
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• pp.719-726
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• 2016

The problem of separation of isotopes in a concurrent gas centrifuge is solved analytically for an arbitrary binary mixture of isotopes. The separative power of the optimised concurrent gas centrifuges for the uranium isotopes equals to ${\delta}U=12.7(V/700m/s)^2(300K/T)(L/1m)kg{\cdot}SWU/yr$, where L and V are the length and linear velocity of the rotor of the gas centrifuge and T is the temperature. This equation agrees well with the empirically determined separative power of optimised counter-current gas centrifuges.

• CDE review
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• v.4 no.2
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• pp.36-41
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• 1998

To survive in the intensive world wide automotive market, more and more automotive companies are investing their resources into concurrent engineering systems (CE) based on the combined CAD/CAM/CAE/ PDM technology. The main objectives of CE in automotive companies are the quality improvement of products and the reduction of cost and time to market. Remarkable effects are appearing from some of these companies. As shown in this paper, these successful automotive companies have been focusing on establishing the new process and methodology in applying CE into their car development process.

• Journal of Pharmaceutical Investigation
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• v.17 no.1
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• pp.31-37
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• 1987

The studies on concurrent administrations of herb preparations(Daesiho-tang, Daehwangmogdanpi-tang, Dohaegseunggi-tang, Baenongsangeub-tang and Jeoryeong-tang) with indomethacin and tetracycline were carried out to investigate the antiinflammatory, antimicrobial, liver-protective and antiulcer activities. The results showed that the concurrent administrations of herb preparations with indomethacin and tetracycline increased significantly the antiinflammatory activities and antimicrobial activities respectively, and also improved the liver-protective activities and antiulcer activities against indomethacin or tetracycline-induced liver defect and Shay ulcers in rats, respectively.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.3
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• pp.965-983
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• 2014

Concurrent behaviors of multithreaded programs cannot be described effectively by automata-based models. Thus, concurrent program intrusion attempts cannot be detected. To address this problem, we proposed the process algebra-based detection model for multithreaded programs (PADMP). We generate process expressions by static binary code analysis. We then add concurrency operators to process expressions and propose a model construction algorithm based on process algebra. We also present a definition of process equivalence and behavior detection rules. Experiments demonstrate that the proposed method can accurately detect errors in multithreaded programs and has linear space-time complexity. The proposed method provides effective support for concurrent behavior modeling and detection.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.1
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• pp.72-77
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• 2011

The checkpointing scheme is a well-known technique to cope with transient faults in digital systems. This paper proposes an adaptive checkpointing scheme for the reliability improvement of real-time control systems with concurrent fault detection capability. With concurrent fault detection capability the effect of transient faults are assumed to be detected with no latency. The proposed adaptive checkpointing scheme is based on the reliability analysis of an equidistant checkpointing scheme. Numerical data show the proposed adaptive scheme outperforms the equidistant scheme from a reliability point of view.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.68-69
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• 2015

Traditional External Insulation Finishing System(EIFS) is applied to apartment construction by performing structural framework and insulation finishing work sequentially. Separate execution of the three works increases construction cost and duration. Concurrent construction method of EIFS, which performs framework and insulation finishing work simultaneously, is introduced in order to solve these problems. However, the introduced method is exposed to the risk of construction delay caused by bottlenecks due to interacting processes and resources. Therefore, this paper presents a simulation model suitable for estimating work productivity of the concurrent construction by considering predecessor and successor processes to optimize resource allocation and minimize construction delay.

• Journal of Korean Society for Quality Management
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• v.29 no.3
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• pp.138-150
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• 2001

Recently, industrial environments have been drastically changed. Customers require cheaper, better, stronger products more than ever. Thus companies have to satisfy the requirements of customers to be survived in this kind of industrial environments. To cope with these requirements from customers, engineers in industries must accept new paradigm and use some special tools for developing new product. This study has applied a Concurrent Engineering which would be good for shortening of product development period in developing of Full Logic Deck mechanism using in car audio. In this paper, a real case of systematic approach and successful story of Concurrent Engineering application in developing Full Logic Deck mechanism is illustrated.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1001-1006
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• 2004

The concurrent engineering technologies have been broadly used in the field of the design, testing, manufacturing and maintenance works to reduce development time and costs. For this purpose, many design environments with the product data management system, the virtual engineering system and web database system are developed. In this research, we developed the driving simulator of the KTX(Korea Train Express) as a basic study for building the concurrent engineering design environment of rolling stock. The virtual track was developed from the Seoul to the Busan and the Daejeon to Mockpo to generate immersible driving environment. Also, fault generation systems were developed to educate drivers of the KTX. We expect to reduce the time and costs of newly developed rolling stock using the design environment developed in the research.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.438-441
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• 2003

Construction delays are a common occurrence of most construction projects and difficult to analyze. there are some techniques to analyze delays, such as using CPM, Bar Chart but they are not enough to analyze concurrent and productivity lost delays. Productivity lost delays are different to interruption delays in computing the number of delays and analyzing concurrent delay. This paper describes the delay analysis method considering productivity including concurrent delay analysis.

• The Journal of Society for e-Business Studies
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• v.1 no.1
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• pp.141-157
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• 1996

Data sharing is a major challenge to implement CALS. STEP is the international standard for the product model data exchange among heterogeneous systems and plays a key role in CALS. Advances in computer networks are rapidly changing the product development processes. The network oriented modeling system premises to integrate design activities across the enterprise. To achieve goals of CALS 3-dimensional concurrent modeling that complies international standard is required since integrity and common perception of product data can be assured. This paper presents 3-dimensional concurrent geometric modeling on high speed network using STEP and methodologies.