• Advances in Energy Research
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• v.8 no.2
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• pp.111-123
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• 2022

Solar Energy is the energy of solar radiation carried by them in the form of heat and light. It can be converted into electricity. Solar potential depends on the site's atmosphere; the solar energy distribution depends on many factors, e.g., turbidity, cloud types, pollution levels, solar altitude, etc. We estimated solar radiation with the help of the Ashrae clear-sky model for three locations in Pakistan, namely Pasni, Gwadar, and Jiwani. As these locations are close to each other as compared to the distance between the sun and earth, therefore a slight change of latitude and longitude does not make any difference in the calculation of direct beam solar radiation (BSR), diffuse solar radiation (DSR), and global solar radiation (GSR). A modified formula for declination angle is also developed and presented. We also created two different models for Ashrae constants. The values of these constants are compared with the standard Ashrae Model. A good agreement is observed when we used these constants to calculate BSR, DSR, GSR, the Root mean square error (RMSE), Mean Absolute error (MABE), Mean Absolute percent error (MAPE), and chisquare (χ²) values are in acceptance range, indicating the validity of the models.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.468-471
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• 2015

The study aims to identify the degree and types of spatial decline in Eup/Myun units within Chungcheong region in South Korea to contribute to the efforts being made to diagnose the rural decline and the potentials. To this end, we analyzed 27 Sis and Guns to identify the degree of decline and potentials of rural areas in Chungcheong region. We also carried out the diagnosis and K-Means Clustering on 274 Eups and Myuns, the smallest administrative units, to figure out the types and characteristics of the rural recessions. According to the results of the clustering analysis carried out on the 166 Eups and Myuns, there were five outstanding clusters. They were; areas with housing deterioration (29), areas with poor economic foundation (16), areas with poor accessibility to central areas (42), areas with poor residential environment (51) and areas with aged population (28). The findings and results of the present study are likely to serve as a basis for the design and enforcement of forthcoming rural area activation policies. Also, it would be highly recommended that a more comprehensive diagnosis is taken from a community-level perspective and policy suggestions and strategies tailored for rural communities are further discussed.

• Journal of Astronomy and Space Sciences
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• v.40 no.3
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• pp.123-129
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• 2023

This paper presents an analysis of the trans-lunar trajectory insertion performance of the Korea Pathfinder Lunar Orbiter (KPLO), the first lunar exploration spacecraft of the Republic of Korea. The successful launch conducted on August 4, 2022 (UTC), utilized the SpaceX Falcon 9 rocket from Cape Canaveral Space Force Station. The trans-lunar trajectory insertion performance plays a crucial role in ensuring the overall mission success by directly influencing the spacecraft's onboard fuel consumption. Following separation from the launch vehicle (LV), a comprehensive analysis of the trajectory insertion performance was performed by the KPLO flight dynamics (FD) team. Both orbit parameter message (OPM) and orbit determination (OD) solutions were employed using deep space network (DSN) tracking measurements. As a result, the KPLO was accurately inserted into the ballistic lunar transfer (BLT) trajectory, satisfying all separation requirements at the target interface point (TIP), including launch injection energy per unit mass (C3), right ascension of the injection orbit apoapsis vector (RAV), and declination of the injection orbit apoapsis vector (DAV). The precise BLT trajectory insertion facilitated the smoother operation of the KPLO's remainder mission phase and enabled the utilization of reserved fuel, consequently significantly enhancing the possibilities of an extended mission.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.1
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• pp.30-38
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• 2009

The objective of this study was to evaluate the effects of occupational exposure to styrene on the components of metabolic syndrome. We surveyed 263 employees, among whom 117workers we ere chronically exposed to styrene in glass-reinforced plastic boat manufacturing factories and 146 controls had never been occupationally exposed to styrene as will as hazardous chemicals. The general and job characteristics such as age, smoking and drinking habit, working hours and duration were not significant different except sleeping hours(p<0.05). Among the components of metabolic syndrome, the systolic blood pressure, total cholesterol, HDL-cholesterol and fasting glucose were significantly higher in exposed workers. On multiple logistic regression analysis for the components of metabolic syndrome, waist circumference was insulin (OR=1.129), blood pressure was MA(OR=14.724), fasting glucose(OR=1.191) and metabolic syndrome(OR=1.110) were significantly associated with insulin. The mean concentration of airborne styrene was $ 38.1{\pm}40.1$ ppm, blood concentrations of glucose and insulin and levels of HOMA-IR in over 50 ppm exposed group were higher than in blow 50 ppm exposed group. These results suggested that the exposure of styrene affects blood pressure, fasting glucose and insulin levels and that dysfunction and/or declination in glucose and insulin metabolism might induced ultimately insulin resistance and metabolic syndrome.

• Journal of the Korean Dietetic Association
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• v.8 no.2
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• pp.175-184
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• 2002

This study is to investigate consequent nutrient intake status, influence of body mass index(BMI), and fat distribution on the silk amino peptide(SAP) and dietary fiber supplementation. During 2 months of this research (January to March, 2002), 45 women aged 20yr – 30yr (average age 24.6yr) were selected as subjects. Nutrient intake was investigated by questionnaire, 24-hr recall method. Antropometric assessments of the subjects were investigated by SBIA method(Segmental bioimpedance assay, In body 3.0). The results are as follows: mean body weight 57.7kg, mean body height 161.9cm mean BMI 22.0, and mean food habit score was 8.47. Defecation frequency was increased by dietary fiber supplementation. Frequency of pain during defecation was significantly decreased by dietary fiber supplementation (p<0.01). Feeling of residual feces was significantly improved by dietary fiber supplementation(p<0.001). Status of energy and carbohydrate intakes significantly decreased after dietary fiber supplementation(P<0.05). Body fat and WHR(waist hip ratio) significantly decreased after dietary fiber supplementation(P<0.001), and percent body fat was decreased by dietary fiber supplementation, significantly(P<0.05). Above results of this study show that dietary fiber-added routine diet improves defecation condition, and lessens body fat, percent body fat without losing body muscle. Especially, declination of abdominal fat and WHR were notable. That meant decreased risk factor.

• Economic and Environmental Geology
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• v.19 no.2
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• pp.153-163
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• 1986

Paleomagnetic and geological studies of volcanic and sedimentary rocks of Jeju Island have been carried out to determine the position of virtual geomagnetic pole(VGP), and to estimate the geological sequence and their age. As a result of paleomagnetic studies, the reversal polarities are measured in the Sanbangsan trachyte and Hwasun formation, and the normal are the rest. In case of normal polarity, the mean values of declination and inclination are $2.3^{\circ}$ and $48.4^{\circ}$, respectively, and the average value of VGP is $85.4^{\circ}N$ and $79.9^{\circ}W$. The locations of VGP's are coincident with those obtained from world-wide Plio-Pleistocene rocks. The Hwasun formation and Seongsan formation which have been known to be sedimented in the similar time in the 2nd-stage of volcanic eruption, possess reversal and normal polarities, respectively. This fact brings about the result that two formations should be separated in a sense of geological sequence. Consequently, the geological sequence of the 2nd-stage of volcanic eruption is Pyoseonri basalt-Seoguipo hawaiite-Hwasun formation-Seongsan formation-Jungmun hawaiite-Sanbangsan trachyte. Referring to the paleomagnetic studies and the previous and present geological studies, Seoguipo formation corresponds to the Gauss normal epoch, the 2nd-stage of volcanic eruption to Matuyama reversed epoch, and the 3rd-, 4th-, and 5th-stages to Brunhes normal epoch. Therefore, the Seoguipo formation is mostly sedimented during late Pliocene and/or presumably extended to the early Pleistocene. The rocks of the 2nd- to 5th-stage are formed later than this.

• Economic and Environmental Geology
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• v.27 no.1
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• pp.49-63
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• 1994

Paleomagnetic study of Tertiary rocks in Pohang area has been carried out to determine the characteristic directon of natural remanent magnetization, the position of paleomagnetic pole, the stratigraphic correlation, and the tectonic movement. A total of 196 specimens was collected from 5 sites in the Pohang Basin, 19 sites in the Janggi Basin, and 10 sites in the Eoil Basin, respectively. The mean declination and inclination of 4 sites (3 sites in the Yonil Group and 1 site in the Yonil Basalt) are $-3.2^{\circ}$ and $54.3^{\circ}$, and yield the paleomagnetic pole position $86.9^{\circ}N$ and $7.7^{\circ}E$. These are the characteristic direction and pole position of Miocene Epoch by comparison with contemporary Eurasian and Chinese data. The characteristic direction and pole position of remaining 30 sites are $47.6^{\circ}$ and $57.5^{\circ}$, and $52.3^{\circ}N$ and $201.5^{\circ}E$, respectively. These show clockwise rotation of $50.8^{\circ}$ with respect to the Miocene ones resulted by a tectonic movement before the deposition of the Hakjeon Formation of the Yonil Group about 15~16 Ma in the study area. The mechanism of the clockwise rotation is considered to be the dextral movement of the Yangsan Fault presumably caused by the opening of the East Sea. The Yonil Basalt is reclassified into pre- and post-deposition of the Yonil Group, i.e. the former is early Miocene and the latter late Miocene.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.3
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• pp.221-228
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• 2013

In areas such as trade area analysis and urban planning, the maturity assessment of central places is important information to be taken into account for rational decision-making. In this study, 3 business areas, typical retail businesses (retail, personal service, food and beverage), are extracted from year 2004 and 2009 phone books, and centrality index and location quotients for 3 business areas are calculated. Using these outputs growth, declination, and maturation of central places are figured out, then comparing and analyzing these results assessment method for central places is proposed. As a result, it is known that the maturity of central place, such as growing, declining, and maturing, can be assessed by comparing the location quotients of 3 retail business areas. In growing central place, location quotient of food and beverage business is much higher than others, and in maturing central place, that of retail business is much higher than others. Assessment results of central places are very useful, as an important index, to determine branch opening or select business area, in trade area analysis.

• Archives of Plastic Surgery
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• v.34 no.6
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• pp.691-696
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• 2007

Purpose: The emergency of multi-drug resistant stains of bacteria represents a challenge in the field of plastic surgery. Especially, MRSA(methycillin-resistant Staphylococcus aureus) and Pseudomonas aeruginosa have strong pathogenicity as well as multi-drug resistance so that they have become a lot more problematic strains. This study has been planned to reduce the bacterial burden by applying $Acticoat^{(R)}$(Smith & Nephew Healthcare, Hull, England)dressing into the chronic wounds infected by multi-drug resistant strains and to facilitate their healing. Methods: Nanocrystalline silver dressings($Acticoat^{(R)}$) were applied to chronic wound infected by MRSA or Pseudomonas aeruginosa. Multi-drug resistant bacteria were smeared over a slide glass using sterilized cotton swabs and gram stains were performed directly before and after applying $Acticoat^{(R)}$ dressings at 1, 24, 48 and 72 hours. The gram-stained slides were observed using an optical microscope magnified 1000 times(${\times}1000$). The bacterial counts of the control group(0 hour) were compared to those of the experimental groups(1, 24, 48, and 72 hour). Paired T-test was used to assess a statistical significance. MRSA was cultured in two BAPs(blood agar plate) and two MacConkey plates with streak plate method. None were interventions on one culture plate, while on the other culture plate, $Acticoat^{(R)}$ was placed in a square shape and cultured for 72 hours at $37^{\circ}C$, then plates were examined. Pseudomonas aeruginosa was cultured in the same manner as MRSA. Results: There are the large amount of declination of bacterial counts with statistical significance after $Acticoat^{(R)}$ dressing. The bacteria grew in culture plate without specific intervention, but no bacteria grew in culture plate with applying of $Acticoat^{(R)}$ dressing. Conclusion: We believe that $Acticoat^{(R)}$ dressing could be used as an effective method of treating chronic wounds which are infected by multi-drug resistant organisms.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.3
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• pp.222-225
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• 2006

The treatment objective of mandibular fracture is a return to normal function. According to Champy, a rigid fixation of mandibular angle fracture is performed by using 4 or 6 holes titanium miniplates on the external oblique ridge of mandible. However, the limitations of metal plate such as hypersensitivity, interference with the cranio-facial growth of growing child, secondary bone resorption around the plate, foreign body reaction, declination of primary callus formation, and bone atrophy due to the lack of normal stress reaction of the bone have been reported. Recently, biodegradable miniplate has been introduced and used as an alternative to the metal plate despite its lower strength than that of the titanium plate and the side effect caused by the resorption in the body. In this study, 61 patients diagnosed as mandibular angle fracture and treated from Jan. 1998 to Dec. 2004 in our department have been reviewed. Metal plate fixation was used in 50 patients and biodegradable plate fixation in 11 patients on the external oblique ridge around the fractured mandibular angle according to the principle of monocortical osteosynthesis by Champy. We compared the incidence of side effects and the degree of bony union at the mandibular inferior border in two different fixation methods. In conclusion, we have found that one miniplate regardless of matter could provide enough strength to grasp bony fragments of the tension site and compress the inferior border of mandible without any complications.