• Journal of the Korean Solar Energy Society
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• v.39 no.3
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• pp.47-57
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• 2019

Clear sky indices were estimated by various ways based on in-situ observation and satellite-derived solar irradiance. In principle, clear sky index defined by clear sky solar irradiance indicates the impacts of cloud on the incoming solar irradiance. However, clear sky index widely used in energy sciences is formulated by extraterrestrial irradiance, which implies the extinction of solar irradiance due to mainly aerosol, water vapor and clouds drops. This study examined the relative difference of clear sky indices and then major characteristics of clear sky irradiance when sky is clear are investigated. Clear sky is defined when clear sky index based on clear sky irradiance is higher than 0.9. In contrast, clear sky index defined by extraterrestrial irradiance is distributed between 0.4 and 0.8. When aerosol optical depth and air mass coefficient are relative larger, solar irradiance is lower due to enhanced extinction, which leads to the lower value of clear sky index defined by extraterrestrial irradiance.

• The Journal of the Korean dental association
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• v.54 no.7
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• pp.563-574
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• 2016

A clear overlay appliance is a type of a removable appliance made from transparent thermoplastic plastic film that covers the entire dentition to move the teeth. It is one of the most favored orthodontic methods opted for by adult patients; this treatment is esthetic, does not cause discomfort and allows oral hygiene to be easily managed when compared to other conventional fixed treatment methods. However, the use of clear overlay appliances, such as invisalign or clear aligner, is associated with various clinical challenges. In particular, the appliances require longer treatment periods compared to fixed treatment, and due to the structural characteristics of the appliances, it is difficult to make proper posterior occlusion and certain type of tooth movement, including extrusion, rotation and tip. Thus, the clear overlay appliances are regarded as supplementary appliances by most orthodontists and have been used for simple orthodontic treatments, such as partial anterior alignments or orthodontic relapse cases. Owing to the remarkable advancement in the field of 3D digital technology over a period of 15 years, the accuracy and convenience of modern clear overlay appliances have continuously improved. Moreover, orthodontic outcomes have also been greatly improved by the introduction of new materials and successful application of various biomechanical methods from conventional orthodontic treatments in the design of clear overlay appliances. This study investigates the clinical limitations that should be considered during the application of clear overlay appliances and also examines the efforts and methods used to overcome these challenges.

• Phonetics and Speech Sciences
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• v.9 no.3
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• pp.67-74
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• 2017

An increase in speech intelligibility has been found in Clear Speech compared to conversational speech. Clear Speech is defined by decreased articulation rates and increased frequency and length of pauses. The objective of the present study was to investigate improvement in immediate speech intelligibility in 10 patients with Parkinson's disease (age range: 46 to 75 years) using Clear Speech. This experiment has been performed using the Phonatory Aerodynamic System 6600 after the participants read the first sentence of a Sanchaek passage and the "List for Adults 1" in the Sentence Recognition Test (SRT) using casual speech and Clear Speech. Acoustic and aerodynamic parameters that affect speech intelligibility were measured, including mean F0, F0 range, intensity, speaking rate, mean airflow rate, and respiratory rate. In the Sanchaek passage, use of Clear Speech resulted in significant differences in mean F0, F0 range, speaking rate, and respiratory rate, compared with the use of casual speech. In the SRT list, significant differences were seen in mean F0, F0 range, and speaking rate. Based on these findings, it is claimed that speech intelligibility can be affected by adjusting breathing and tone in Clear Speech. Future studies should identify the benefits of Clear Speech through auditory-perceptual studies and evaluate programs that use Clear Speech to increase intelligibility.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.271-278
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• 2016

Forest clear-cutting operations influence biodiversity through habitat changes and food resource availability for inhabitant species. This study examined the effects of clear-cutting on forest arthropod communities. Arthropods were collected from two different forest treatment areas (clear-cut and control) in summer and autumn. In each treatment area, arthropods were sampled from both crown and ground surfaces using sweeping and pitfall trap methods, respectively. Then, the taxonomic order of the collected arthropod specimens was easily identified. Results indicate that arthropod abundance and number of taxa present were higher at ground surface than at crown levels in both clear-cut and control areas. At crown level, more homopteran species were present in clear-cut areas than in control areas in summer. At ground surface, populations of Isopoda and Opiliones were higher in control areas than in clear-cut areas, whereas numbers of Araneae, Orthoptera, and Hymenoptera were greater in clear-cut areas. Cluster analysis and principal component analysis showed distinct differences between clear-cut and control communities at crown level in summer and at ground surface in autumn. Thus, our results indicate that clear-cutting significantly influences arthropod communities, and higher taxa are valuable for conducting rapid biological assessments of ecosystem disturbances.

• Korean Journal of Applied Biomechanics
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• v.24 no.1
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• pp.11-18
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• 2014

The purposes of this study were to analyze the kinematics and electromyographic variables of the upper extremity for the backhand clear motion according to the type of hitting in badminton. Seven elite male university players were selected as the subjects. Four digital video cameras and Noraxon Telemyo 2400 were used to collect the 3D kinematics and electromyographic data. The results were as follows: 1) in the phase of impact, the time of motion for the overhead backhand clear was the longest, 2) in the event of impact, the distance of step toward X direction was the longest and the distance of step toward Y direction was the shortest for the overhead backhand clear, 3) in the event of backswing, the rotation angles of shoulder and pelvis and the flexion angle of shoulder for the overhead backhand clear were the biggest, 4) the maximum flexion angular velocity of shoulder and the maximum extension angular velocity of elbow for the overhead backhand clear were the biggest, and 5) in the phase of impact, mean EMG of the wrist flexor, triceps, and trapezius muscle for the overhead backhand clear was bigger than that for the underhand stroke and in the phase of follow-through, mean EMG of the wrist flexor and extensor, biceps, triceps, and trapezius muscle for the overhead backhand clear was the biggest.

• Korean Journal of Applied Biomechanics
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• v.13 no.3
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• pp.217-229
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• 2003

The purpose of this study was to present the basic data on improving the skills for 3 junior high school national badminton players in clear and drop motion through the 3-dimensional image analysis. Therefore, the results of this study are as follows: 1. In the duration times per phase, subject C relatively showed a similar time between clear and drop motion. Accordingly, C took a more effective motion than A and B. 2. In the velocities of racket head, subject A and C showed similar changes relatively. However, in case of subject B, the velocity was decreased before back swing(E2) and increased until impact(E3). 3. Regardless of clear and drop motion, the changing phases of joint angle for wrist and elbow showed similar changes comparatively. 4. In the angles of upper body, clear motion was average 85.0 degree and drop one was average 80.7 degree during the impact(E3). Hence, it showed that drop motion hit the ball bowing the upper body more than clear one. 5. In the angles of racket head, clear motion was average 87.7 degree and drop one was average 85.6 degree during the impact(E3). Consequently, drop motion was impacted forward more than clear one.

• The Journal of the Korean dental association
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• v.54 no.7
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• pp.551-562
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• 2016

There are interferences between the teeth to be moved and the clear aligner made from setup. These interferences generate forces which move teeth to the desired position. However, these can cause incomplete tooth capture of clear aligner. When these interferences exceed the acceptable deformation of aligner, unwanted intrusion of teeth to be moved occurs. When correction of rotation or tipping of teeth is attempted, intrusion prevails before rotation or tipping. However, clear aligner can induce labiolingual tipping or intrusion easily. To achieve preliminary alignment including control of rotation and tipping, NiTi archwires with fixed appliance can be used first, and then clear aligner can be used for finishing in mild Class I maloccusion cases. For this purpose, clear aligner can be made using a digital setup and 3D printing. To move teeth using a clear aligner, tooth capture is critical. To improve tooth capture of clear aligners, slingshot or vertical elastics can be used. These were discussed with illustrations.

• Journal of Audiology & Otology
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• v.23 no.4
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• pp.187-192
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• 2019

Background and Objectives: Clear speech is an effective communication strategy used in difficult listening situations that draws on techniques such as accurate articulation, a slow speech rate, and the inclusion of pauses. Although too slow speech and improperly amplified spectral information can deteriorate overall speech intelligibility, certain amplitude of increments of the mid-frequency bands (1 to 3 dB) and around 50% slower speech rates of clear speech, when compared to those in conversational speech, were reported as factors that can improve speech intelligibility positively. The purpose of this study was to identify whether amplitude increments of mid-frequency areas and slower speech rates were evident in Korean clear speech as they were in English clear speech. Subjects and Methods: To compare the acoustic characteristics of the two methods of speech production, the voices of 60 participants were recorded during conversational speech and then again during clear speech using a standardized sentence material. Results: The speech rate and longterm average speech spectrum (LTASS) were analyzed and compared. Speech rates for clear speech were slower than those for conversational speech. Increased amplitudes in the mid-frequency bands were evident for the LTASS of clear speech. Conclusions:The observed differences in the acoustic characteristics between the two types of speech production suggest that Korean clear speech can be an effective communication strategy to improve speech intelligibility.

• The Korean Journal of Cytopathology
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• v.9 no.2
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• pp.213-219
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• 1998

Glycogen-rich clear ceil carcinoma of the breast is an unusual variant of carcinoma with a recorded incidence of $1.4{\sim}3%$ of breast carcinomas. The cytologic characteristics have not been well described. We report two cases of glycogen-rich clear cell carcinoma with corresponding fine needle aspiration(FNA) cytologic findings and compare them to infiltrating ductal carcinoma and other clear ceil malignancies with a review of literature. One was a 62-year-old woman exhibiting a palpable mass of the right breast. The smears showed atypical tight cell clusters and individually scattered single cells containing leanly or clear abundant cytoplasm with well defined cytoplasmic margins. Mild to moderate nuclear pleomorphism and a prominent nucleolus were present. The other was a 42-year-old woman who was admitted with a right breast mass. The smears showed moderately cellular, tightly cohesive tumor cells. The cytoplasmic outline was generally well demarcated. The tumor cells Contained foamy to clear abundant cytoplasm with large and small vacuoles. The nuclear pleomorphism was marked. Both tumors resected by modified radical mastectomy, were diagnosed as glycogen-rich clear cell carcinoma. Histologically, the clear cell nature of tumor cells were not characteristic enough to predict this type of the tumor. Some cytologic features can be distinguished other clear cell breast cancer from glycogen-rich carcinoma. Recognition of these unusual patterns in a breast FNAC should raise the suspicion of a clear cell carcinoma including glycogen-rich subtype. Cytological localization of glycogen using PAS and D-PAS staining may permit the correct Identification and differential diagnosis of this tumor.

• Journal of the Korean Solar Energy Society
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• v.26 no.3
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• pp.53-62
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• 2006

Since the direct normal radiation and clear day are a main factor for designing any solar thermal and photovoltaic concentrating system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of direct normal radiation and clear day in Korea. The data utilized in the investigation consist of direct normal radiation collected for 14 years('90. 12${\sim}$2004. 12) and clear-day collected for 23 years($1982{\sim}2004$) at measuring stations across the country. The analysis shows that the annual-average daily direct normal radiation is 5.4 kWh/m2 and the annual-average total clear-day is 92.7 days in Korea. We also constructed the contour map of direct normal radiation and clear-day in Korea by interpolating actually measured data across the country.