• IE interfaces
• /
• v.9 no.3
• /
• pp.120-142
• /
• 1996

Asynchronous Transfer Mode (ATM) is considered to be the most promising transfer technique for BISDN due to its efficiency and flexibility. Queueing theory has been playing a very important role in performance evaluation of ATM for the past few years. This paper is composed of two parts. The first part is concerned with the several basic concepts of ATM. The second part surveys queueing approaches in ATM performance evaluation. It deals with stochastic models which have been proposed for the three basic categories of traffic sources (voice, data, video), various queueing models for statistical multiplexer and switch, and priority strategies for buffer control schemes.

• Journal of the Korean Society of Safety
• /
• v.12 no.2
• /
• pp.3-16
• /
• 1997

In modern high performance engineering applications, the structural integrity of materials and structures are quite often evaluated using fracture mechanics. This evaluation in turn requires information on the flaw geometry (location, type, shape, size, and orientation). The ultrasonic nondestructive evaluation (NDE) method is one technique that is commonly used to provide such information. Flaw classification (determination of the flaw type ) and flaw sizing (prediction of the flaw shape, orientation and sizing parameters) are very important issues for quantitative ultrasonic NDE. In this paper new approaches to both classification and sizing of flaws are described together with extensive review of previous works on both topics. In the area of flaw classification, a methodology is developed which can solve classification problems using probabilistic neural networks, and in the area of flaw sizing, a time-of-flight equivalent (TOFE) sizing method is presented. The techniques proposed here are in a form that can be used directly in many practical applications to quantitative estimates of the flaw's significance.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.7 no.1
• /
• pp.24-33
• /
• 2004

Recently, ship acoustics takes more important role in acoustic stealth and classification of underwater targets. In this paper, a theoretical concept is proposed for M＆S-based test and evaluation of ship acoustics. The concept is based on two different approaches: on Top-Down method which emphasizes the survivability of the ship and on Bottom-Up method which considers acoustic characteristics of the ship-equipments. In order to improve the effectiveness of M＆S-based T＆E for ship acoustics, it is recommended in this paper to compromise the two approaches as adequate.

• Design Convergence Study
• /
• v.15 no.4
• /
• pp.59-70
• /
• 2016

Due to the newly emerging market for telepresence robots and the research in the area, designers and developers lack guidelines for specifying the physical characteristics of telepresence robots. On the basis of the previous literature, we attempted to make a distinction between two robot height approaches for telepresence robot designs: floor- versus desk-based robot designs. This research investigated the effects of these robot height approaches on consumer acceptance. We predicted that there would be difference between floor-based robots and desk-based robots regarding consumers' evaluation of and intent to purchase social robots. A study using two types of robots was conducted with sixty university students. The results showed that participants perceived desk-based robots as more useful than floor-based robots. In addition, the participants evaluated desk-based robots more positively than floor-based robots. Purchase intention and willingness to pay also showed similar results as evaluation. The implications for the design of telepresence robots in terms of increasing acceptance of robots are discussed in detail.

• The Journal of Information Systems
• /
• v.3
• /
• pp.133-145
• /
• 1994

Performance evaluation is essential for the successful management and operation of MIS. The more MIS grows and relevant investment enlarges, the more performance evaluation grows in importance. However, MIS managers as well as top management still have difficulty in evaluating the performance of MIS. This arises from various reasons, such as the specialty of MIS, diversified influences of MIS, multidimensionality of evaluation items, and the difference between evaluation levels. In this paper, MIS is understood in a broad sense. MIS's scope is of a very wide range from each application system to system innovation view. The MIS should support the firm's objectives, and, consequently, MIS evaluation should be implemented at corporate level, not merely at application system level. The most critical problem of MIS evaluation is that a systematic frame covering various viewpoints and factors of MIS evaluation does not exist. Not a single measure covers all aspects of MIS evaluation. To help resolve this problem, this paper proposes an hierarchical approach for practical use that includes most aspects of evaluation approaches from previous studies, and, furthermore, emphasizes the evaluation of strategic aspects of MIS.

• Proceedings of the Korean Society of Toxicology Conference
• /
• 2003.10b
• /
• pp.89-90
• /
• 2003

Biological products are composed of vaccines, antitoxin, blood products, DNA recombinant protein drugs, monoclonal antibody, cell therapy and gene therapy. Biological products are divided into traditional (i.e. recombinant proteins and monoclonal antibodies) and novel biological products (gene and cell therapy) and will require a similar re-evaluation of the approaches taken during each development program.(omitted)

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2019.05a
• /
• pp.145-146
• /
• 2019

• Journal of Soil and Groundwater Environment
• /
• v.17 no.6
• /
• pp.69-81
• /
• 2012

Diverse geostatistical tools such as kriging have been used to estimate the volume and spatial coverage of contaminated soil needed for remediation. However, many approaches frequently yield estimation errors, due to inherent geostatistical uncertainties. Such errors may yield over- or under-estimation of the amounts of polluted soils, which cause an over-estimation of remediation cost as well as an incomplete clean-up of a contaminated land. Therefore, it is very important to use a better estimation tool considering uncertainties arising from incomplete field investigation (i.e., contamination survey) and mathematical spatial estimation. In the current work, as better estimation tools we propose stochastic simulation approaches which allow the remediation volume to be assessed more accurately along with uncertainty estimation. To test the efficiency of proposed methods, heavy metals (esp., Pb) contaminated soil of a shooting range area was selected. In addition, we suggest a quantitative method to delineate the confident interval of estimated volume (and spatial extent) of polluted soil based on the spatial aspect of uncertainty. The methods proposed in this work can improve a better decision making on soil remediation.

• Journal of Information Science Theory and Practice
• /
• v.2 no.4
• /
• pp.31-48
• /
• 2014

The proliferation of many interactive Topic Detection and Tracking (iTDT) systems has motivated researchers to design systems that can track and detect news better. iTDT focuses on user interaction, user evaluation, and user interfaces. Recently, increasing effort has been devoted to user interfaces to improve TDT systems by investigating not just the user interaction aspect but also user and task oriented evaluation. This study investigates the combination of the bag of words and named entities approaches implemented in the iTDT interface, called Interactive Event Tracking (iEvent), including what TDT tasks these approaches facilitate. iEvent is composed of three components, which are Cluster View (CV), Document View (DV), and Term View (TV). User experiments have been carried out amongst journalists to compare three settings of iEvent: Setup 1 and Setup 2 (baseline setups), and Setup 3 (experimental setup). Setup 1 used bag of words and Setup 2 used named entities, while Setup 3 used a combination of bag of words and named entities. Journalists were asked to perform TDT tasks: Tracking and Detection. Findings revealed that the combination of bag of words and named entities approaches generally facilitated the journalists to perform well in the TDT tasks. This study has confirmed that the combination approach in iTDT is useful and enhanced the effectiveness of users' performance in performing the TDT tasks. It gives suggestions on the features with their approaches which facilitated the journalists in performing the TDT tasks.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.5C
• /
• pp.313-322
• /
• 2006

Liquefaction of soil foundation is one of the major seismic damage types for infrastructures. In this paper, deterministic and probabilistic approaches for the evaluation of liquefaction potential are briefly summarized and the risk assessment method is newly proposed using seismic fragility and seismic hazard analyses. Currently the deterministic approach is widely used to evaluate the liquefaction potential in Korea. However, it is very difficult to handle a certain degree of uncertainties in the soil properties such as elastic modulus and resistant capacity by deterministic approach, and the probabilistic approaches are known as more promising. Two types of probabilistic approaches are introduced including (1) the reliability analysis (to obtain probability of failure) for a given design earthquake and (2) the seismic risk analysis of liquefaction for a specific soil for a given service life. The results from different methods show a similar trend, and the liquefaction potential can be more quantitatively evaluated using the new risk analysis method.