• Journal of the Korean Society of Systems Engineering
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• v.11 no.2
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• pp.61-73
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• 2015

The early-phase naval ship design demands requirements synthesis rather than design synthesis, which conducts engineering design for several domains on a detailed level. Requirements synthesis focuses on creating a balanced set of required operational capabilities satisfying user's needs and concept of operations. Requirements are evolved from capability based languages to function based language by statistical exploration and engineering design which are derived in the following order: concept alternative, concept baseline, initial baseline and functional baseline. The early-phase naval ship design process can be divided into three passes: concept definition, concept exploration and concept development. Main activities and outcomes in each pass are shortly presented. Concept definition is the first important step that produces a concept baseline through extensive design space exploration promptly. Design space exploration applies a statistical approach to explore design trends of existing ships and produce feasible design range corresponding to concept alternative. It further helps naval systems engineers and operational researchers by inducing useful responses to user and stakeholders' questions at a sufficient degree of confidence and success in the very early ship design. The focus of this paper is on the flow of design space exploration, and its application to a high-speed patrol craft. The views expressed in this paper are those of the authors, and do not reflect the official policy or rule of the Navy.

• Journal of Korean Elementary Science Education
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• v.24 no.3
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• pp.214-225
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• 2005

The purpose of this study was to examine the content relevance of the 7th national primary science curriculum and textbooks. To fulfill the purpose of the study, we 1) analyzed the 7th national science curriculum of Korea, Californian science standards, the national science curriculum of England and Japan, and current Korean and Japanese science textbooks, 2) conducted a nationwide survey to gather opinions from students, teachers, and professors of teachers colleges about the relevance of the science curriculum and textbooks. Main findings of this study are as follows: First, the science contents at each grade level should be determined by the students' characteristics, not by an equal portion rule among physics, chemistry, biology and earth science. Second, the excessive overlapping and repetition of contents due to the spiral curriculum should be avoid. Third, the number of topics at each grade level should be reduced, and the similar topics and themes should be integrated for students' deeper understanding. Fourth, the number of science concepts and activities should be reduced to an appropriate level considering the time allotment for science classes, teachers workload, laboratory conditions, etc. Fifth, differentiated curriculum, such as in-depth and supplementary course, should be described not in science contents, but in teaching and learning strategy.

• Clinical and Experimental Reproductive Medicine
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• v.18 no.1
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• pp.113-120
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• 1991

Etiologic classification was performed in 155 patients with recurrent spontaneous abortion history. The incidence was 9.3% among 1658 pregnant women at Hanyang university hospital during the same period. In etiologic classification, 37 cases of on-going patients for diagnostic evaluation were excluded. Of the remained 118 patients, the patients with unknown etiology were 32 cases (27.1%), and 86 cases were classified into each etiologies using appropriate diagnostic modalities. Anatomic causes were the largest etiology, which revealed 46.6% (55 among 118 patients). The next etiology was immunologic cause, which revealed 24.6% (29 patients). Of the 86 patients who have at least one cause, 40.7% (35 among 86) have two or more etiologies. Furthermore, six cases (7%) have 3 combined etiologies. The uterine synechia and/or incompetent internal os of the cervix, namaly anatomic causes, revealed highest combination ratio than other etilogies. The popular abortion technique in Korea, D&C, seems to be main factors for these anatmic causes. The combined causes rather than single cause of recurrent spontaneous abortion were unique situation in Korea especially with anatomic etiologies. From this point of view, we think anatomic etiologies should be rule out first in the evaluation of the patients. For this purpose, we believe hysteroscopy would be helpful as a diagnostic work-up and treatment modality in the management of recurrent spontaneous abortion patients in Korea.

• Journal of the Society of Naval Architects of Korea
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• v.38 no.1
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• pp.116-122
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• 2001

In this paper, to make a base of the fire safety assessment about ship's fire protection design and Classification Society rule, statistical informations and modeling techniques for the fire safety engineering are investigated and probabilistic safety assessment methods in the structural reliability engineering are introduced. FSEM(Fire Safety Evaluation Module) developed in this paper calculates the probability of fatality, which can be used as an index of fire safety. FSEM is used to calculate the probability of fatality of the evacuees in a small room installed according to the rules for fire-proof. Sensitivity analysis is executed to investigate FSEM's applicability to ship. From results, the necessity of new criterion for ship's fire safety design, the need to study the human behavior in the evacuation from fire, and the development of new fire progress model considering special situations in ships are acknowledged.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.2
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• pp.273-278
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• 2010

A few small and medium enterprise administer its organization systematically, but most of them is affected by ability and level of a CEO rather than organization system. In this viewpoint, it can be said the study on ability and level of CEO in small and medium enterprise are so meaningful. Thus, in this paper, the core competency of CEO is obtained from the CEO through questionnaire and it is suggested the evaluation model of the CEO core competency. Also patterns were analyzed by ID3 and fuzzy ID3 from data on expert appraise for CEO core competency and level. The 'if-then' fuzzy rules and decision tree created by results of pattern analysis showed their usefulness for evaluation of CEO core competency in small and medium enterprise.

• Composites Research
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• v.14 no.2
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• pp.8-12
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• 2001

Filament Winding Process is a comparatively simple operation in which continuous reinforcements in the form of roving are wound over a rotating mandrel. It is well established and versatile method for storage tanks and pipes for the chemical and other industries. In this study, tensile strength of a filament wound ring specimens were evaluated by a split disk test fixture and a dress disk test fixture. The results obtained from experiments were compared with the theoretical values from the rule of mixtures. The purpose of this paper is the suggestion of an appropriate test method for the evaluation of tensile properties of filament wound structures. The tensile strength of a ring specimen tested by the dress disk test showed better agreement with the theoretical values than those tested by the split disk test because of higher stress concentration in edges of a split disk test fixture. The results showed that the tensile strength of a ring specimen was influenced by the geometry of test fixture, the continuity of fibers, fiber-tension, fiber-end and stress concentration in specimen.

• Journal of Biosystems Engineering
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• v.42 no.4
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• pp.251-257
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• 2017

Purpose: A chisel mounted on working implement, such as agricultural machinery used in irregular farming conditions, is subjected to highly variable fatigue loading during work. To ensure the safety of the chisel on a working implement for the duration of its service life, fatigue testing must be performed with the proper fatigue test load conditions. In this study, working loads for a chisel were developed by reconstructing loads from strain gage data collected during field tests and used to conduct fatigue tests on the chisel component. Methods: FE analysis with nCode software was utilized to select the proper quantity and locations of strain gages for load measurements. A fatigue test was performed to experimentally verify the fatigue strength of the chisel and to evaluate the validity of the load history developed with the load reconstruction technique. Results: A strain history for the chisel was obtained from data collected during field tests. The data was filtered for the 14-16 km/h speed range, connected, and merged. The chisel load history was developed using the load reconstruction technique. The resulting load history was expressed as a load spectrum using the rain-flow counting method. Conclusions: A fatigue test was conducted on a chisel under a constant load condition with an equivalent load amplitude and number of cycles, as calculated by Miner's Rule for linear damage accumulation. During the fatigue test, there were no cracks at any position. It is concluded that the fatigue test method proposed in this study can be utilized successfully as a durability evaluation method for the chisel.

• The Journal of Korean Obstetrics and Gynecology
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• v.28 no.4
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• pp.46-56
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• 2015

Objectives : Cold hypersensitivity has been regarded to be associated with Autonomic Nervous System (ANS). This study aims to investigate the indicator of cold hypersensitivity of hands and evaluate the correlation between indicator of coldness of hands and Heart Rate Variability (HRV). Methods : We studied 55 patients with cold hypersensitivity of hands who visited in SeMyung University Hospital from 17 August 2015 to 21 August 2015. Thermometer and VAS scale were used for the diagnosis of cold hypersensitivity. After careful examination to rule out other disease which may affect thermometer and HRV data, patients were taken thermometer, those with thermal difference between upper arm (L4) and palm(P8), also asked to answer a VAS scale of cold hypersensitivity of hands, VAS more than 4 were enrolled for evaluation. Results : There was significant correlation between L4-P8 temperature difference and VAS score of cold hypersensitivity. In HRV data, normalized high frequency (HF normal) was significantly correlated with L4-P8 temperature difference, which was objective indicator of cold hypersensitivity of hands. Conclusions : L4-P8 temperature difference using thermometer is objective indicator of cold hypersensitivity, based on VAS scale. Cold hypersensitivity is highly related with ANS, regulating body heat and temperature. HRV is considered to be widely used in cold hypersensitivity in hands for evaluation of ANS.

• Speech Sciences
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• v.10 no.4
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• pp.201-219
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• 2003

Background: The perceptual assessment is generally performed by the voice specialist. The objective evaluation is performed in a voice laboratory. Research in voice laboratories has generated a variety of different objective tests and parameters. The perceptual evaluation is one of the most controversial topics in voice research. Review of literature reveals a wide variety of rating scales and reliability data fluctuating from study to study. Unfortunately, there is no widely accepted valid method for classifying voice disorders and assessing outcome after voice treatment. Objectives: The goals of this research were to identify important objective acoustic parameters of vocal quality, and to establish an objective and quantitative correlate of the perceived vocal quality. Materials and Methods : We evaluated the voice analyzed data from 122 dysphonic patients and 20 normal volunteers. A computerized speech lab. 4300B(CSL) was used to carry out the analysis of each voice sample. Results: Three dysphonia severity indices(DSI) were created using discriminant analysis. DSI is based on the weighted combination of the following selected set of acoustic parameters: absolute jitter(Jita in us), smoothed pitch period perturbation (sPPQ in %), amplitude perturbation quotient(APQ in %), soft phonation index(SPI), average fundamental frequency(Fo in Hz), lowest fundamental frequency(Flo in Hz), and smoothed amplitude perturbation quotient(sAPQ in %). The DSI, being the discriminating rule calculated by the logistic regression, consists of three equation based on statistically significant acoustic parameters. Three DSI were created to reflects best the degree of hoarseness as expressed by G from the GRBAS scale. The more positive this DSI is for a patient, the worse the vocal quality. The more it is negative, the better it is. The effect of sex is included implicitly in the DSI-1 and DSI-2, so that a separate DSI-1 and DSI-2 for males and females need not be used. The DSI is objective because no perceptual input is required for its calculation. Conculsion : This research demonstrates that the voice function values calculated from three different multivariate objective dysphonia severity indices are significantly associated with subjective voice assessments. These multivariate objective dysphonia severity indices may be appropriate for use in clinical trials and outcomes research on treatment effectiveness for voice disorders.

• KDI Journal of Economic Policy
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• v.33 no.4
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• pp.143-177
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• 2011

Upon selecting preferred bidder in Public-Private Partnership projects, multi-dimensional procurement auction, where price factor and non-price factor are evaluated, is used. This paper tries to analyze bidding data in BTO road projects. It is shown that a winner tends to get higher score in bidding evaluation, which is partly due to increase in base score as well as fiercer competition among bidders. It turns out that score margin in non-price factor was determinant in selecting winner. Also, there was no competition when the level of bonus point was set too high. For price factor, it costs 730 million KRW per score in construction subsidy by government, while it costs 2.43 billion KRW per score in toll revenue. For non-price factor, it was estimated to cost 2.30 billion KRW. Based on the results, it was suggested that we should have appropriate level of bonus point for first initiator, change in scoring rule in construction subsidy part, adjustment of base score in evaluation.