• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.1
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• pp.77-100
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• 2022

In the era of low growth, many provincial cities are experiencing population decline and aging. Population decline phenomena such as reduction of productive manpower, reduction of finances, deterioration of quality of life, and collapse of the community base are occurring in a chain and are being pushed to the brink of extinction of the cities. This study aims to propose a methodology to objectively estimate the employment creation centers and setting the basic unit of industrial-centered zoning by applying spatial statistical techniques and GIS for the application of the compact city plan as an efficient spatial management policy in a city with a declining population. In details, based on reviewing previous studies on compact city, 'employment complex index(ECI)' were defined considering the number of workers, the number of settlers, and the area of development land, the employment creation center was estimated by applying the 'Local Moran's I' and 'Getis-Ord's Hot-Spot Analysis'. As a case study, changes in the four years of 2013, 2015, 2017, and 2019 were compared and analyzed for Changwon City. As a result, it was confirmed that the employment creation center is becoming compacted and polycentric, which is a significant result that reflects the actual situation well. This results provide the basic data for functional and institutional territorial governance for the regional revitalization platform, and provide meaningful information necessary for spatial policy decision-making, such as population reduction, regional gross domestic product, and public facility arrangement that can respond to energy savings, transportation plans, and medical and health plans.

• Journal of Broadcast Engineering
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• v.28 no.2
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• pp.213-229
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• 2023

In this paper, we introduce a spatial sound rendering system that provides 6DoF spatial sound in real time in response to the movement of a listener located in a virtual environment. This system was implemented using MPEG-I AEP as a development environment for the CfP response of MPEG-I Immersive Audio and consists of an encoder and a renderer including a decoder. The encoder serves to offline encode metadata such as the spatial audio parameters of the virtual space scene included in EIF and the directivity information of the sound source provided in the SOFA file and deliver them to the bitstream. The renderer receives the transmitted bitstream and performs 6DoF spatial sound rendering in real time according to the position of the listener. The main spatial sound processing technologies applied to the rendering system include sound source effect and obstacle effect, and other ones for the system processing include Doppler effect, sound field effect and etc. The results of self-subjective evaluation of the developed system are introduced.

• Analytical Science and Technology
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• v.20 no.1
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• pp.17-24
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• 2007

This study was performed to investigate the distributions of volatile organic compounds and carbonyl compounds at the 120 households in new apartments before occupation. The concentration of toluene, m, p-xylene, formaldehyde, acetone and ethylbenzene dominated as $272.81{\mu}g/m^3$, $98.90{\mu}g/m^3$, $71.68{\mu}g/m^3$, $70.58{\mu}g/m^3$ and $49.76{\mu}g/m^3$, respectively. The identified compounds by standards occupied 42.5% of the TVOCs, also the concentration of toluene occupied the largest part of the identified compounds as 18.5%. The concentration of formaldehyde and acetone were 43.1% and 42.4% among carbonyl compounds. The indoor/outdoor ratio of the concentration of benzene, toluene, formaldehyde and o-xylene were investigated 1.29, 3.59, 10.76 and 28.74, respectively.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.4
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• pp.158-165
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• 2010

Phytoplankton community structure is one of the indicators that can explain the enviromnental characteristics of coastal waters. In this study, phytoplankton community structure and water quality of aquaculture area were investigated for understanding regional enviromnental characteristics. Thirty stations in aquaculture areas of Tongyeong, southeast coast of Korea, were investigated monthly from January to December, 2009. Phytoplankton community, meteorologic dada and enviromnent factors including temperature, salinity, transparency, nutrients and chlorophyll a were also examined. Chaetoceros spp. and unidentified small flagellates were dominant species in all the year round. Pseudo-nitzschia spp., Dictyocha spp., and Nitzschia longissima were dominant in June to October being summer season, and Skeletonema costatum, Thalassiosira spp., Eucamphia zodiacus, Akashiwo sanguinea, Gymnodinium spp. and Asterionella japonicus appeared as dominant species in the rest of months. Dinoflagellate blooms occurred 3 times in near Hansan Bay and around Saryang-do, and the highest chlorophyll a was found in Hansan Bay. Species diversity of phytoplankton was lower in Hansan and Womnum Bay, and diatom was more abundant than dinoflagellates in Mireuk-do waters. These results showed that phytoplankton community varied by the seasonal and geographical characteristics, and recent increase of water temperature and heavy rain may affect on phytoplankton community structure.

• Journal of Bio-Environment Control
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• v.33 no.2
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• pp.99-106
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• 2024

The objective of the experiment was to determine the sprout emergence and asparagus seedling growth characteristics of six cultivars ('Apollo', 'Atlas', 'Grande', 'Purple Passion', 'UC157', and 'Walker Deluxe') according to growth stage to select suitable cultivar in the Korean climate condition. As a result of examining the growth characteristics of the seedlings of each cultivar during the dormancy, bud break, early fern growth and fern establishment stages, green asparagus cultivar 'UC157' had a higher number of spears, number of roots and buds, root length, and fresh and dry weights of root than the other cultivars. Green asparagus cultivars, 'Atlas' and 'UC157' were released from dormancy considerably earlier than other cultivars. In contrast, a purple asparagus cultivar 'Purple Passion' was showed to lower growth characteristics than those of other cultivars. Proper thermal insulation will be required when the seedling stage of asparagus is damaged by low temperature in winter. These results indicated that the 'UC157' cultivar showed characteristics of good seedlings and bud break compared to other cultivars and is thus expected to have the highest yield among all cultivars tested.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.2
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• pp.93-104
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• 2002

A field survey and experiment was conducted from 1996 to 1998 to develop rational technology for turfgrass vegetation of runway side of Incheon International Airport on the reclaimed tidal land in Young-Jong Island. Backfill of the experimental site was finished on August 1995. The experimental site was 8 ha located in the middle of the construction place for the main parking lot in front of the terminal building construction. The experimental field was drained by main open ditch, and divided three main plots, no subsurface tile drain, subsurface tile drain spacing with 22.5m, and with 45 m, respectively. The 17 sub plots were designed to test the effect of soil covering with red earth loam by 5 cm and 20 cm depth, application of chemical compound fertilizers and livestock manures, dressing of artifical soils and hydrophylic soil conditioners. The tested turfgrasses were three transplanting indigenous turfgrasses, Zoysia koreana, Zoysia sinica and Zoysia japonica, and two hydroseeding mixed exotic turgrasses, cool type I(tall fescue 30%, kentucky blue grass 40%, perenial ryegrass 30%), and cool type II(tall fescue 40%, perenial ryegrass 20%, fine fescue 20%, alkaligrass 20%). The soil backfilled with dredged seasand was sand textured with high salt concentration and low fertility. The soil showed high pH, low organic matter and low available phophate contents. The percolation rate was fast with high hydraulic conductivity. Desalinization was fast after installation of the main open drainage system. No subsurface tile drainage effect was found showing little difference in turfgrass growth. The covering and visual growth of turfgrasses were the best in the 20-cm soil covering with compound fertilizer treatment. The covering and visual growth of turfgrasses were satisfactory in the 5 cm soil covering with compound fertilizer treatment and with livestock manure treatments. The hydrophillic soil conditioner treatments were effective but expensive at present. The coverage and visual quality of turfgrasses were good for Zoysia koreana and Zoysia japonica. The coverages of turfgrasses by the hydroseeding with the mixed exotic turfgrasses were less than transplanting of native turfgrasses. In conclusion, for the runway side vegetation purposes, the subsurface tile drainage might not necessary as main open ditch drainage be sufficient due to fast percolation rate of the backfilled dredged seasand. The 5 cm soil covering with red earth might be sufficient for the runway side, but the 20 cm soil covering might be necessary for the runway side where high density of turfgrass coverage was necessary to protect from the airplance air blow.

• Journal of Yeungnam Medical Science
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• v.4 no.2
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• pp.121-129
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• 1987

To evealuate the status of hepatitis B virus infection in the mothers and neonates and to determine the maternal-neonatal transmission of hepatitis B virus, 2,276 term pregnant women were screened for the presence of serum HBsAg, at the Department of Obstetrics and Gynecology, Yeungnam University Hospital, during the period of 18 months from Jan. 1986 to Jun. 1987, and the sera of sixty-six HBsAg carrier mothers and their neonates were tested for HBV markers and liver enzymes. The results were as follows : 1. The prevalence rate of asymptomatic HBsAg carrier in the term pregnant women was 4.7%(53/1,279). 2. Positive rates of HBsAg and anti-HBs 10 the sera of sixty-six neonates born to asymptomatic HBsAg carrier mothers were 12.1% and 9.1%, respectively. Transient elevation of SGOT(three to four times of upper normal limit) was detected in one of eight HBsAg-positive neonates and one of six anti-HBs positive neonates. 3. Positive rates of anti-HBc, HBeAg and anti-HBe to the sera of sixty-six asymptomatic HBsAg carrier term pregant women were 93.9%, 45.5% and 50%, respectively. The rates of transmission of maternal anti-HBc, HBeAg and anti-HBe to the neonates were 85.5%(53/62), 90%(27/30) and 87.9%(29/33). respectively. 4. Serum HBsAg was detected in four of thirty neonates born to HBeAg positive HBsAg carrier mother, three of thirty-three neonates born to anti-HBe positive HBsAg carrier mothers, and one of three neonates born to both HBeAg and anti-HBe negative HBsAg carrier mothers.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.3
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• pp.157-164
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• 2016

In this study, researchers performed preliminary design and numerical analysis for a pilot-scale helium heating system intended to support full-scale construction for a sulfur-iodine (SI) cycle. The helium heat exchanger used a liquefied petroleum gas (LPG) combustor. Exhaust gas velocity at the heat exchanger outlet was approximately 40 m/s based on computational thermal and flow analysis. The maximum gas temperature was reached with six baffles in the design; lower gas temperatures were observed with four baffles. The amount of heat transfer was also higher with six baffles. Installation of additional baffles may reduce fuel costs because of the reduced LPG exhausted to the heat exchanger. However, additional baffles may also increase the pressure difference between the exchanger's inlet and outlet. Therefore, it is important to find the optimum number of baffles. Structural analysis, followed by thermal and flow analysis, indicated a 3.86 mm thermal expansion at the middle of the shell and tube type heat exchanger when both ends were supported. Structural analysis conditions included a helium flow rate of 3.729 mol/s and a helium outlet temperature of $910^{\circ}C$. An exhaust gas temperature of $1300^{\circ}C$ and an exhaust gas rate of 52 g/s were confirmed to achieve the helium outlet temperature of $910^{\circ}C$ with an exchanger inlet temperature of $135^{\circ}C$ in an LPG-fueled helium heating system.

• Advances in pediatric surgery
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• v.1 no.2
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• pp.149-161
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• 1995

The first national survey on esophageal atresia and tracheoesophageal fistula was conducted to access the current status of its incidence, clinical manifestation, preoperative diagnosis and management, type of its anomaly, associated anomalies, and surgical results and course. The 43 members of the Korea Association of Pediatric Surgeons received questionnaires and registration forms to be filled out on each patient who were born during the three years from January 1, 1992 through December 31, 1994. Questionnaires composed of six broad areas which include 1) preoperative diagnosis and management, 2) surgical technic, 3) long gap, 4) postoperative management, and 5) complications and courses. A total of 148 cases was returned by 28 members working at 23 institutions and 27 members returned questionnaires. We obtained the following results by analysis of the 148 cases of tracheoesophageal anomalies. The incidence of tracheoesophageal anomaly was about 1/10,000-11,000 in 1994, which is one third of that of anorectal malformations in Korea and the distribution of the patients was almost proportionate to the size of each province. Both sexes are about equally affected. Majority of the members make diagnosis of tracheoesophageal anomaly by taking a simple infantogram with a radiopaque tube in upper pouch and a little under half(46%) prefers to perform echocardiography as a part of preoperative management to identify congenital heart disease and lateralize the aorta. Esophageal atresia with distal TEF(87.5%) was by far the most common and there were pure esophageal atresia(5.6%), H-type TEF(2.1%), and so on. About half(49%) of the patients had one or more associated anomalies in addition to tracheoesophageal anomalies. Congenital heart disease was associated in 46 cases(31%), anorectral malfomations in 19 cases(13%), musculoskeletal anomalies in 15 cases(10%), genitourinary anomalies in 10 cases(7%) and gastrointestinal anomalies in 7 cases(5%). Postoperatively, parenteral nutrition and assisted ventilation were given in 66% and 52% of patients respectively. Ninety three(74%) of 126 cases who underwent sugical procedure, experienced one or more complications such as respiratory complication(65%), leak(22%), stricture(21%) and so on. The survival rates related to the Waterston risk categories were 90.2% in group A, 71.4-75% in $B_1$, $B_2$, and $C_1$, groups, and 28% in group $C_2$, and the overall survival rate was 71.4%. Thirty six(28.6%) of 126 cases died of pneumonia/sepsis(12 cases), respiratory failure(12 cases), and congenital heart disease(4 cases). With short term follow-up, 69% of patients have been excellent whereas remainders of the cases have suffered from some sort of morbidity related to gastroesophageal reflux, recurrent respiratory infection, and esophageal stricture.

• The Journal of the Korean bone and joint tumor society
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• v.6 no.2
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• pp.53-60
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• 2000

Purpose : The purpose of the current study is to evaluate the functional and oncologic results of the limb salvage surgery with intramedullary nailing and cementization in malignant bone tumors of the proximal humerus. Materials and Methods : We reviewed 18 cases of limb salvage surgery of resection and reconstruction with an intramedullary nail and cement-molded humeral head for the malignant bone tumors of the proximal humerus, which performed between August, 1992 through the April, 1998. The diagnoses included the osteosarcoma in 7 patients, chondrosarcoma in 3, the recurrent giant cell tumor in 3, metastatic tumor in 3, multiple myeloma in one patient and the one patient with malignant fibrous histiocytoma. The mean age at the time of surgery was 38 years(range, 15-73 years). The mean follow-up period was 26 months(range, 6-67 months). Results : Average functional score by ISOLS evaluation system was 21.1(70.3%). There were 3 local recurrences and 5 distant metastases. There were one case of shoulder instability and one case of deep infection. The seven patients are continuously disease free state and seven patients are alive with disease. Four patients died from the disease. Conclusion : The limb salvage surgery with intramedullary nailing and cementization in the bone tumors of the proximal humerus may be considered an option for the malignant bone tumors of the proximal humerus in selected patients.