• Journal of the Korean Society for information Management
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• v.21 no.3
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• pp.289-303
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• 2004

This experimental study proposes a multi-document summarization method that produces optimal summaries in which users can find answers to their queries. In order to identify the most effective method for this purpose, the performance of the three summarization methods were compared. The investigated methods are sentence clustering, passage extraction through spreading activation, and clustering-passage extraction hybrid methods. The effectiveness of each summarizing method was evaluated by two criteria used to measure the accuracy and the redundancy of a summary. The passage extraction method using the sequential bnb search algorithm proved to be most effective in summarizing multiple documents with regard to summarization precision. This study proposes the passage extraction method as the optimal multi-document summarization method.

• Restorative Dentistry and Endodontics
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• v.43 no.3
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• pp.29.1-29.13
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• 2018

Objectives: The aims of this study were to conduct a systematic review of the microtensile bond strength (${\mu}TBS$) of multi-mode adhesives to dentin and to perform a meta-analysis to assess the significance of differences in the ${\mu}TBS$ of one of the most commonly used universal adhesives (Scotchbond Universal, 3M ESPE) depending on whether the etch-and-rinse or self-etch mode was used. Materials and Methods: An electronic search was performed of MEDLINE/PubMed, ScienceDirect, and EBSCOhost. Laboratory studies that evaluated the ${\mu}TBS$ of multi-mode adhesives to dentin using either the etch-and-rinse or self-etch mode were selected. A meta-analysis was conducted of the reviewed studies to quantify the differences in the ${\mu}TBS$ of Scotchbond Universal adhesive. Results: Only 10 studies fulfilled the inclusion criteria for the systematic review. Extensive variation was found in the restorative materials, testing methodologies, and failure mode in the reviewed articles. Furthermore, variation was also observed in the dimensions of the microtensile testing beams. The meta-analysis showed no statistically significant difference between the etch-and-rinse and self-etch modes for Scotchbond Universal adhesive (p > 0.05). Conclusions: Multi-mode 'universal' adhesives can achieve substantial bonding to dentin, regardless of the used modes (either etch-and-rinse or self-etch).

• Korean Journal of Computational Design and Engineering
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• v.10 no.6
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• pp.432-443
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• 2005

Recent three-dimensional feature-based CAD systems based on solid or non-manifold modelling functionality have been widely used for product design in manufacturing companies. When product models associated with features are used in various downstream applications such as analysis, however, simplified and abstracted models at various levels of detail (LODs) are frequently more desirable and useful than the full detailed model. To provide multi-resolution models, the features need to be rearranged according to a criterion that measures the significance of the feature. However, if the features are rearranged, the resulting shape is possibly different from the original because union and subtraction Boolean operations are not commutative. To solve this problem, in this paper, the new concept of the effective zone of a feature is defined and identified using Boolean algebra. By introducing the effective zone, an arbitrary rearrangement of features becomes possible and arbitrary LOD criteria may be selected to suit various applications. Besides, because the effective zone of a feature is independent of the data structure of the model, the multi-resolution modelling algorithm based on the effective zone can be implemented on any 3D CAD system based on conventional solid representations as well as non-manifold topological (NMT) representations.

• Korean Journal of Acupuncture
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• v.24 no.3
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• pp.33-45
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• 2007

Background : Hot flushes are general postmenopausal symptoms which about 75% of climacteric women undergo. They affect hotness, perspirations, systemic weakness, panic disorders, insomnia. Acupuncture is effective in alleviating hot flushes in practice. Assessment effectiveness and safety of acupuncture in hot flushes would be needed through multi-center trial. Objectives : Purpose of this study is to develope the protocol of effects of acupuncture on hot flushes, a postmenopausal symptom in climacteric women. Methods & Results : It will be a multi-centered, randomized, sham controlled, comparative trial. It will be performed by Good Clinical Practice after approval of Institutional Review Board. Selection criteria will be set according those of FDA above moderate degree. There will be a notice on concomitant medication, other herbs, dietary supplements. Superficial needling on sham points will be used for control group. Treatment period will be 8 weeks with 12 weeks' follow up. Some questionnaire scale will be used as the primary and secondary outcome. Conclusions : The clinical trials based on this protocol will be performed.

• Journal of Communications and Networks
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• v.11 no.3
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• pp.279-286
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• 2009

This paper proposes an adaptive mode switching algorithm between two strategies in multiple antenna cellular networks:A single-user mode and a multi-user mode for the broadcast channel. If full channel state information is available at the base station, it is known that a multi user transmission strategy would outperform all single-user transmission strategies. In the absence of full side information, it is unclear what the capacity achieving method is, and thus there are few criteria to decide which of the myriad possible methods performs best given a system configuration. We compare a single user transmission and a multi user transmission with linear receivers in this paper where the transmitter and the receivers have multiple antennas, and find that neither strategy dom inates the other. There is instead a transition point between the two strategies. Then, the mode switching point is determined both ana lytically and numerically for a multiple antenna cellular downlink with correlation between transmit antennas.

• Steel and Composite Structures
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• v.31 no.5
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• pp.517-527
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• 2019

To move forward in large steps rather than in small increments, the community would benefit from a systematic and comprehensive database of multi-scale composites and measured properties, driven by comprehensive studies with a full range of types of fiber-reinforced polymers. The multi-scale hierarchy is a promising chemical approach that provides superior performance in synergistically integrated microstructured fibers and nanostructured materials in composite applications. Achieving high-efficiency thermal conductivity and mechanical properties with a simple surface treatment on single-walled carbon nanotubes (SWCNTs) is important for multi-scale composites. The main purpose of the project is to introduce ozone-treated SWCNTs between an epoxy matrix and basalt fibers to improve mechanical properties and thermal conductivity by enhancing dispersion and interfacial adhesion. The obvious advantage of this approach is that it is much more effective than the conventional approach at improving the thermal conductivity and mechanical properties of materials under an equivalent load, and shows particularly significant improvement for high loads. Such an effort could accelerate the conversion of multi-scale composites into high performance materials and provide more rational guidance and fundamental understanding towards realizing the theoretical limits of thermal and mechanical properties.

• Journal of the Korean Society of Systems Engineering
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• v.16 no.2
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• pp.1-15
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• 2020

Nuclear power plants in South Korea are operated to cover the baseload demand. Hence they are operated at 100% rated power and do not deploy power tracking control except for startup, shutdown, or during transients. However, as the contribution of renewable energy in the energy mix increases, load follow operation may be needed to cover the imbalance between consumption and production due to the intermittent nature of electricity produced from the conversion of wind or solar energy. Load follow operation may be quite challenging since the operators need to control the axial power distribution and core reactivity while simultaneously conducting the power maneuvering. In this paper, a systems engineering approach for multi-physics load follow simulation of APR1400 is performed. RELAP5/SCDAPSIM/MOD3.4/3DKIN multi-physics package is selected to simulate the Korean Advanced Power Reactor, APR1400, under load follow operation to reflect the impact of feedback signals on the system safety parameters. Furthermore, the systems engineering approach is adopted to identify the requirements, functions, and physical architecture to provide a set of verification and validation activities that guide this project development by linking each requirement to a validation or verification test with predefined success criteria.

• Journal of Korean Society on Water Environment
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• v.29 no.2
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• pp.259-269
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• 2013

This study aims to show the feasibility of wastewater reuse through hydrological analysis and propose a framework for planning using multi-criteria decision making technique. Ten alternatives of wastewater reuse (BOD: 3.0 mg/L & 4.7 mg/L) and two references in the urban watershed were considered and analyzed by using Hydrological Simulation Program in Fortran (HSPF). Though wastewater reuse has a positive effect on water quantity, it may degrade the water quality due to the high discharge concentration. This study showed that wastewater reuse can be a great alternative for the rehabilitation of distorted water cycle, if the quality is improved up to the natural streamflow and the quantity is increased up to the instreamflow requirement. In addition, to determine the project priority, three criteria were compared: 1) impacts on water quantity and water quality, respectively, 2) consideration of present hydrologic vulnerabilities on water quantity and quality and not, and 3) social and economic considerations and not. From the performance values to all criteria, the specific ranking can be derived and the feasibility of each wastewater reuse project can be checked with the comparison of the existing facilities. As a result, DJ and DR were derived to become effective in any evaluation conditions while SS and WG were improper alternatives if various criteria were considered. The decision making for project prioritization must be careful with the consideration of various impacts of wastewater reuse because the evaluation of wastewater reuse alternative showed very different priorities for each criteria.

• The Korean Journal of Applied Statistics
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• v.13 no.2
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• pp.393-405
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• 2000

Box and Draper( 19(5) listed some properties of a design that should be considered in design selection. But it is impossible that one design criterion from optimal experimental design theory reflects many potential objectives of an experiment, because the theory was originally based on the underlying model and its strict assumption about the error structure. Therefore, when it is neces::;ary to implement multi-objective experimental design. it is common practice to balance out the several optimal design criteria so that each design criterion involved benefits in terms of its relative "high" efficiency. In this study, we proposed several composite design criteria taking the case of heteroscedastic model. WVhen the heteroscedasticity is present in the model. the well known equivalence theorem between 1)- and C-optimality no longer exists and furthermore their design characteristics are sometimes drastically different. We introduced three different design criteria for this purpose: constrained design, combined design, and minimax design criteria. While the first two methods do reflect the prior belief of experimenter, the last one does not take it into account. which is sometimes desirable. Also we extended this method to the case when there are uncertainties concerning the error structure in the model. A simple algorithm and concluslOn follow.On follow.

• Land and Housing Review
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• v.7 no.4
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• pp.251-259
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• 2016

As the spatial structure of a region is evolving into a decentralized multi-nucli model, networked connection among cities in a region is emerging as an important issue to strengthen regional competitiveness. This paper focused on the limitation of current new town planning criteria which just suggest a uniform standard for economic self-sufficiency by new-town size, without representing the network characteristics of new town. If a new town is planned as a economic strongpoint within a region, it needs to secure appropriate industrial functions. This study classified the characteristics of new towns by network analysis and reviewed the economic self-sufficiency criteria by new town types. Using various network connectedness indices, the 1st and 2nd round new towns in the capital region were analyzed, and land-use distribution of new-towns in other countries were also examined comparatively. The network characteristics of new towns are classified as three types: mono-nucleus, distributed center, and dependent. Based on this classification, planning criteria for self-sufficiency were compared among 6 new towns. This study provides implications for the amendment of "the sustainable new town planning criteria" or the revision of development plans.