• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.4
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• pp.30-35
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• 1983

Numerical calculations have been made about the phase differences of the short circuit current in a solar cell according to the variation of the modulation frequency. The phase differences in short circuit current of the solar cell exposed to the modulated light source is measured experimentally. From the above two results, the minority carrier lifetime has been determined. Also, minority carrier lifetime has been determined from the observed photo-induced open circuit voltage decay wave form that follows termination of the excitation.

• Journal of the Korean Chemical Society
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• v.17 no.4
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• pp.240-246
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• 1973

An analytic expression for the intensity of collision-induced light scattering obstained by introducing both short-range and long-range effects on the induced anisotropy. By taking argon as a specific example, it is shown that a narrow band at small frequency shifts is caused by long-range effects, while a broad band in the far wing of the spectrum is due to short-range effects. The overall intensity is a synthesis of these two bands and does not follow a simple exponential form. As temperature increases, the intensity at large frequency shifts increases makedly, while at small frequency shifts it changes little.

• Structural Engineering and Mechanics
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• v.55 no.5
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• pp.931-951
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• 2015

To improve the durability and service life of reinforced concrete column such as bridge piers, an advanced composite column made of Ultra High Performance Cementitious Composites (UHPCC) permanent form is proposed. Based on elasticity plasticity theory, axial compression behavior of the composite column was studied theoretically. The first circumferential cracking load and ultimate limit loading capacity are derived for the composite column. Short composite column compression tests and numerical simulations using FEM method were carried out to justify the theoretical formula. The effects of UHPCC tube thickness on the axial compression behavior were studied. Using the established theoretical model and numerical simulation, the large dimension composite columns are calculated and analyzed with different UHPCC tube thickness. These studies may provide a reference for advanced composite column design and application.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2386-2388
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• 2005

As anti-crash and pre-crash systems in vehicles become more extensively used, the need for high performance short-range radars is playing an increasing role. This paper presents the design of a micromachined, ultra-wideband beamformer centered at 24 GHz for automotive short-range radar systems. This beamformer is a Butler matrix designed using ultra-wideband transmission-line couplers, which consist of a multilayered structure that exhibits wider bandwidth compared to conventional microstrip branch-line couplers. The circuit has been designed on a quartz substrate, and to achieve the desired coupling, lines suspended on BCB layers located at specific parts of the circuit were used, achieving a three metal layered structure in form of wide microstrips, that give low loss and a wideband response. In this paper the design and fabrication procedure of the proposed beamformer are fully described.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.136-137
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• 2006

Crack initiation and short crack propagation was studied on the polished notched surfaces of Cr-Mo prealloy sintered steels with 7.35 $g.cm^{-3}$ sintered density. An ultrasonic resonance test system operating in push-pull mode at 20 kHz and R=-1 was used. It showed that crack initiation took place in several places, small cracks growing oriented to the local pore structure rather than to stress orientation. Their growth rate is markedly higher than the corresponding one of long cracks. Finally, several microcracks join to form a dominant crack.

• Science of Emotion and Sensibility
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• v.20 no.1
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• pp.95-104
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• 2017

This study aims to develop a reliable and valid Geriatric Reaction Inventory-Simplified Form (GRI-SF). Reaction inventory for measuring anger (Evans & Stangelang, 1971) is an assessment tool in a view of stimuli for measuring the level of anger invoked from the anger-triggered experiences. Yet, the inventory, comprised of 76 items, is sometimes incapable of finishing up the lengthy questionnaire. In the sense, a simplified form of RI is necessary for those lacks cognitive ability such as stroke patients or the elderly. In study 1, a full version of Reaction Inventory was given for the elder who are above 60, and ten items out of 76 was selected to form GRI-SF based on the psychometric theory. In study 2, the reliability and validity of GRI-SF was tested by another sample group of elderly with some additional examinations. The reliability was good with Cronbach's alpha of 0.79. Based on the fact that GRI-SF measures the personal trait anger, GRI-SF should not be only strong correlation with the scores of trait anger strongly, but be less correlated with scores representing other aspects of anger. As a result, GRI-SF score showed strong correlations with trait anger among other sub-categories of State-Trait Expression Inventory (STAXI), and was less correlated with anger-out score which reflects behavioral aspect of anger. Moreover, it is less correlated (r=.41) with hostility representing attitudinal or cognitive aspects of anger. Consequently, GRI-SF, constructed by this research, is verified to be a reliable and valid tool for anger measurement.

• Journal of Oral Medicine and Pain
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• v.36 no.2
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• pp.81-89
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• 2011

The purpose of this study was to evaluate the individually perceived quality of life in Korean patients with BMS using two questionnaires : the Medical Outcome Short Form Health Survey Questionnaire (SF-36) and the Oral Health Impact Profile (OHIP-49). This cross-sectional study included sixty subjects diagnosed with BMS and sixty healthy subjects as controls. All subjects in this study completed two questionnaires: the Medical Outcome Short Form Health Survey Questionnaire (SF-36) and the Oral Health Impact Profile (OHIP-49), which had been translated into Korean and subsequently validated for use in Korea. All of the subscales in the SF-36 exhibited significantly lower scores in BMS patients than control groups. Comparison of the mean SF-36 scores between the two groups revealed the greatest differences to be for the subscales of physical pain and role emotional (role limitations due to emotional problems). The mean score on each subscale of the OHIP-49 was significantly higher in BMS patients than control groups. Comparison of the mean OHIP-49 scores between the two groups revealed the greatest difference to be for the subscale of physical pain. These findings demonstrated that BMS had an impact on various components of a patient's quality of life. BMS patients exhibited more impaired results and a poorer quality of life than control groups.

• The Journal of the Korea Contents Association
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• v.13 no.12
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• pp.321-327
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• 2013

Impaired naming difficulty is common in normal elderly as well as in patients with neurological impairment. The 60-item Korean version-Boston Naming Test(K-BNT) is one of the most commonly used test for measuring confrontational naming ability. However, age-related cognitive decline may make the elderly difficult concentrating during the 60-item test, therefore, item reduction of the K-BNT would improve test validity and reliability. Thus, the purpose of this study was to develop a short form of the K-BNT based on Item Response Theory(IRT). Considering item-fit index, sex factor, and item difficulty through Rasch analysis, the 15-item K-BNT(i.e., K-BNT-15) was developed. Via administration of the K-BNT-15, we observed age-related decline in naming ability and significantly different performance between the normal elderly and patients with mild cognitive impairment. This study demonstrates the utility of IRT for developing a short-form language evaluation tool. The K-BNT-15 can be effective as a language screening tool to differentiate between normal aging and pathological diseases.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.225-235
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• 2016

This study aims at developing Reminiscence Function Scale-Short Form(RFS-S) and verifying it as a supplemental diagnosis instrument to judge differences between normal and mild cognitive impairment and useful measure to rate effects of reminiscence therapy in the clinical field through internal consistency reliability and criterion validity. The study also aims at figuring out factors affection reminiscence function by figuring out demographic features of RFS-S. The research subjects were the control group of 60 normal people and experimental group of 58 people with mild cognitive impairment and both groups were over 65 years old. For internal consistency reliability(Cronbach's alpha) between questions was reliable with 0.63. Convergent validities of RFS-S with SRT and CDR-SB were 0.20(p<.05) and -0.25(p<.001), respectively, as both showed significant correlations. As a result of criterion validity to analyze AUROC, it was 0.68(p<.001) and less accurate. Its optimal cut-off points were 17 and sensitivity according to them was 0.59, and specificity was 0.72, respectively. However, reminiscence function according to demographic variables did not show any significant differences. Therefore, it is expected that RFS-S will be used as a supplemental diagnosis instrument with higher reliability and validity for discerning differences between normal and mild cognitive impairment and as a useful one to verify effects of reminiscence therapy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.4
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• pp.121-127
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• 1972

The present paper deals with the results of the comparative morphology on the urohyal bones on the right-eye flounders, pleuronectidae fishes in Korean waters. The results obtained are as follows : 1. The position of the tip of sciatic part is quite different depending on the genera and species of the fishes. The sciatic part of the genera, Platichthys and Cleisthenes, is very short extending to the middle portion of the main part. In the fishes of Eopsetta and Tanakius, it is also very short extending to the anterior 1/3 of the distance from the tip of main part. The fishes of Verasper and Dexistes have a short sciatic part which extends toward the posterior 1/4 of the distance from the tip of main part. The fishes Of Limanda, Clidoderma, Glyptecephalus and Microstomus have a long sciatic part which extends as long as the main part. However, those of Kareius and Pleuronichthys have a very long sciatic part extending twice long as the main part. The tip of sciatic part of the fishes belonging to Eopsetta, Verasper, Limanda, Platichthys, Tanakius and Glyptocephalus is a truncate form. It is pointed upward in the fishes of Kareius, Pleuronichthys, Clidoderma and Microstomus, but pointed forward in Cleisthenes and Dexistes. 2. The size and form of the cardiac apophysis vary with the developmental grades of the urohyal bone. The fishes of Eopsetta, Verasper, Platichthys, Tanakius, Kareius and Dexistes possess relatively large apophyses and those of Pleuronichthys and Clidoderma have small apophyses. Intermediate size of the apophysis is found in the fishes of Limanda, Microstomus and Cleisthenes. A long and barlike apophysis is found in Glyptocephalus. Three kinds of the cardiac. apophysis are found in the fishes examined, i. e., lateral wing in Eopsette, Verasper, Limanda, Platichthys, Tanakius, Glyptocephalus, Kareius, Pleuronichthys and Clidoderma, pointed forward in Microstomus and Cleisthenes, and truncate with a well-developed inner ridge type in Dexistes. 3. The angle of the main part and sciatic part varies from 30 to 60 degrees in the fishes studied except for the fishes of Pleuronichthys, Clidoderma and Microstomus which show a semi-elliptical form.