• Journal of Biosystems Engineering
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• v.39 no.2
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• pp.87-95
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• 2014

Purpose: The purpose of this study was to design a variable frequency LED light system for plant factory which combined red, blue, green, white, and UV lights and controlled the ratio of the light wavelength. In addition, this study evaluated the performance of each combination of LED to verify the applicability. Methods: Four combinations of LED (i.e. Red+Blue, Red+Blue+Green, Red+Blue+White, Red+Blue+UV) were designed using five types of LED. The system was designed to control the duty ratio of each wavelength of LED by 1% interval from 0~100%, the pulse by 1Hz interval from 1~20kHz. Response characteristics of the control system, spectral distribution of each combination, light uniformity and uniformity ratio were measured to test the performance of the system. Results: Clean waveforms were measured from 10Hz to 10kHz regardless of duty ratio. Frequency distortion was observed within 5% of inflection point at frequencies above 10kHz regardless of duty ratio, but it was judged negligible. Spectra showed a normal distribution, and maximum PPF with duty ratio of 100% was $271.4{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ for the Red+Blue combination. PPF of the Red+Blue+Green combination was $258.9{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and that of the Red+Blue+White combination was $273.9{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. PPF of the Red+Blue+UV combination was $267.7{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Uniformity ratio for the area excepting border showed 0.90 for the Red+Blue and Red+Blue+White combinations, 0.87 for the Red+Blue+Green combination, and 0.88 for the Red+Blue+UV combination. The light was irradiated evenly at the area excepting border, so it was suitable for plant growing. Conclusions: From the results of this study, response characteristics of the control system, spectral distribution of each combination, light uniformity and uniformity ratio were suitable for applying into the plant factory.

• Journal of the Korean association of regional geographers
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• v.10 no.4
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• pp.698-712
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• 2004

As EU's enlargement toward Central and Eastern countries, it is expected to change of the economic activity space of EU. This paper aims to examine the changing of economic activity space of EU with a locational analysis of foreign direct investment in Central and Eastern countries. The foreign enterprises, particularly EU's firms are increasing the direct investment in the Central and Eastern countries from the middle 1990's for a raising of the efficiency of production and a prior occupation of the potential market. The foreign direct investment in Central and Eastern Europe has a tendency to concentrate in Poland, Hungary, Czech and Slovakia, which has relatively a large market, a cheap and plentiful labor, a stable political system and a positive inviting policy of foreign direct investment. And, the foreign direct investment shows a tendency to locate generally in a big city, which has a advantageous production factors by a well-developed infrastructure and a regional industrial organization, a skilled labors, a market, etc., and in a border area between East and West Europe because of a cheap and plentiful labor, a similar cultural environment and the low cost of transportation. In conclusion, as an integration of the Central and Eastern countries into EU, the capital territories of Hungary, Czech and Poland, and the border area between East and West Europe is becoming a new economic activity space of EU with a location of foreign direct investment. And. the Baltic zone is also expect to become a new economic activity space according to the augmentation of exchanges and direct investment inter near countries.

• Journal of Wetlands Research
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• v.24 no.4
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• pp.268-287
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• 2022

This study reports newly discovered seven forest wetlands in the western part of the Korean Demilitarized Zone-Civilian Control Zone ecoregion. The wetland assessment criteria proposed by National Arboretum were adopted to evaluate four fields: vegetation and landscape, biogeochemical cycle, hydraulics and hydrology, and social-cultural-historical landscape and disturbances. Among seven wetlands located in Gimpo and Paju, five were of the fallow field type and two were of the natural type. A total of 474 plant species were recorded, including nine rare plants, such as the Carex capricornis Meinsh. ex Maxim. Three forest wetlands were sorted into A-grade, three into B-grade, and one into C-grade. Monitoring forest wetlands scattered across the border area ruled by military regulations can be challenging; still, as forest wetlands with high conservation value turned out, further investigations through remote sensing and cooperation by the relevant agencies will be required.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.3
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• pp.235-258
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• 2022

We interpreted the evolutionary history of the southwestern part of the Pohang Basin, the largest Miocene basin in the southeastern part of the Korean Peninsula, based on the detailed geological mapping and analysis of the geological structures. The southwestern part of the Pohang Basin can be divided into the Bomun Domain in the west and Ocheon Domain in the east by an NNE-trending horst-in-graben. These two domains have different geometries and deformation histories. The Bomun Domain was rarely deformed after the incipient extension of the basin, whereas the Ocheon Domain is an area where continued and overlapped deformations occurred after the basin fill deposition. Therefore, the Bomun Domain provides critical information on the initial extension mode of the Pohang Basin. The subsidence of the Bomun Domain was led by the zigzag-shaped western border fault that consists of NNE-striking normal and NNW-striking dextral strike-slip fault segments. This border fault is connected to the Yeonil Tectonic Line (YTL), a regional dextral principal displacement zone and the westernmost limit of Miocene crustal deformation in SE Korea. Therefore, it is interpreted that the Pohang Basin was initially extended in WNW-ESE direction as a transtensional fault-termination basin resulting from the movement of NNE-striking normal and/or oblique-slip faults formed as right-stepover in the northern termination of the YTL activated since approximately 17-16.5 Ma. As a result, an NNE-trending asymmetric graben or half-graben exhibiting an westward deepening of basin depth was formed in the Bomun Domain. Afterward, crustal extension and deformation were migrated to the east, including the Ocheon Domain.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.20 no.2
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• pp.65-71
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• 1984

As a primary step in studying the relationship between the arrangement of netting and the section shape of the bag net in the four-seam trawling net, a series of experiments were performed with the simplified model of the bag net made of vinyl film. This model was suspended horizontally in circularly flowing water, with two pairs of suspending threads to four points of symetry at the border of the bag mouth in place of both wing nets. And then, the area distribution of each panel in the bag net was arranged by the portion of the length of the side panel, q to that of the lower or upper panel, p at the border of bag mouth. In the experiments, the section shape of the bag mouth photographed and the tensions on both pairs of suspending threads were measured with two loadcells in circularly flowing water. From the results that the section shape of the bag mouth in circularly flowing water is controlled by the area distribution of panels in the bag net, the author estimated an experimental equation. h/w=k sub(1) e super(k) 2 super(q/p)+C, where h is the central height of the bag mouth, and w is the lateral width of that.

• Korean Journal of Ecology and Environment
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• v.49 no.3
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• pp.197-207
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• 2016

This study aims at providing basic data to objectively evaluate the areas suitable for reintroduction of the species of Asiatic black bear (Ursus thibetanus) in order to effectively preserve the Asiatic black bears in the Korean protection areas including national parks, and for the species restoration success. To this end, this study predicted the potential habitats in East Asia, Southeast Asia and India, where there are the records of Asiatic black bears' appearances using the Maxent model and environmental variables related with climate, topography, road and land use. In addition, this study evaluated the effects of the relevant climate and environmental variables. This study also analyzed inhabitation range area suitable for Asiatic black and geographic change according to future climate change. As for the judgment accuracy of the Maxent model widely utilized for habitat distribution research of wildlife for preservation, AUC value was calculated as 0.893 (sd=0.121). This was useful in predicting Asiatic black bears' potential habitat and evaluate the habitat change characteristics according to future climate change. Compare to the distribution map of Asiatic black bears evaluated by IUCN, Habitat suitability by the Maxent model were regionally diverse in extant areas and low in the extinct areas from IUCN map. This can be the result reflecting the regional difference in the environmental conditions where Asiatic black bears inhabit. As for the environment affecting the potential habitat distribution of Asiatic black bears, inhabitation rate was the highest, according to land coverage type, compared to climate, topography and artificial factors like distance from road. Especially, the area of deciduous broadleaf forest was predicted to be preferred, in comparison with other land coverage types. Annual mean precipitation and the precipitation during the driest period were projected to affect more than temperature's annual range, and the inhabitation possibility was higher, as distance was farther from road. The reason is that Asiatic black bears are conjectured to prefer more stable area without human's intervention, as well as prey resource. The inhabitation range was predicted to be expanded gradually to the southern part of India, China's southeast coast and adjacent inland area, and Vietnam, Laos and Malaysia in the eastern coastal areas of Southeast Asia. The following areas are forecast to be the core areas, where Asiatic black bears can inhabit in the Asian region: Jeonnam, Jeonbuk and Gangwon areas in South Korea, Kyushu, Chugoku, Shikoku, Chubu, Kanto and Tohoku's border area in Japan, and Jiangxi, Zhejiang and Fujian border area in China. This study is expected to be used as basic data for the preservation and efficient management of Asiatic black bear's habitat, artificially introduced individual bear's release area selection, and the management of collision zones with humans.

• Archives of Plastic Surgery
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• v.33 no.6
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• pp.784-788
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• 2006

Purpose: For the reconstruction of the ankle joint as well as the soft tissue defect in the distal lower leg, a free flap or a local flap has been used, and because of the condition of patients, if a complex microvascular surgery under general anesthesia could not be performed, it could be reconstructed by using the distally based lateral supramalleolar fascio-cutaneous island flap using the perforating branch of the peroneal artery in the ankle area. Methods: The study subjects were 4 male patients between 53 years and 73 years of age. 2 cases were tissue defect in the medial malleolus area due to systemic diseases such as gouty arthritis accompanied traffic accident, diabetes mellitus foot, atherosclerotic obliterans, etc., 1 case was the defect in the pretibia area, and 1 case was the defect underneath the lateral malleolus, which was reconstructed by the distally based lateral supramalleolar fascio-cutaneous island flap. The donor area was the skin harvested from the groin, and the full thickness skin graft was performed. The size of the flap varied from $4{\times}3cm$ to $9{\times}6cm$. As the flap border, the medial side was to the tibialis anterior tendon, the lateral side was to the fibula crest, and the proximal area was less than the fibula size. Results: The consequence is that, in total 4 cases, the congestion in the flap began from 12 hours after the surgery, and the progression of congestion was ceased on the 5th day after the surgery, and finally epidermal bulla and sloughing, partial necrosis was developed. After the end of necrosis, the defect area was reconstructed successfully by the second full thickness skin graft. Conclusions: Although the distally based lateral supramalleolar fascio-cutaneous island flap has the shortcoming of requiring the second skin graft, it has the advantages that it does not require a long complex microsurgery, the flap itself is thin, it is similar to the color of the skin in the recipient area, and it does not leave a big scar in the donor area. Therefore, it is thought that for the cases who could not undergo a long complex surgery due to systemic diseases or the cases of patients whose condition of the recipient area is not suitable for microsurgery, the lateral supramalleolar fascio-cutaneous island flap is very useful for the reconstruction of the distal lower leg and the ankle joint area.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.2
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• pp.71-75
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• 2006

The aggregates made of clay, carbon and $Fe_2O_3$ were prepared to investigate the mechanism of black core formation and the property differences at various sintering atmospheres. The aggregates were sintered at oxidized, neutralized and reduced atmospheres. The specific gravity, absorption rate, percent of black core area were measured at various compositions and sintering atmospheres. The aggregates sintered at oxidized atmosphere showed clear border between shell and black core area. Hence, the aggregates sintered at reduced and neutralized atmospheres showed only black core area in the cross-section of the aggregates. The specific gravity of the aggregates sintered at reduced atmosphere increased with increasing carbon contents and that was the lowest of all aggregates sintered at various atmospheres. Adsorption rate increased with increasing carbon contents at all atmospheres.

• Archives of Plastic Surgery
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• v.37 no.5
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• pp.667-670
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• 2010

Purpose: The management of urethral defect represents one of the most challenging clinical problems in uroplastic surgery. Especially for defect after Fournier's Gangrene, optimal management is still a hard problem. During extensive urethral reconstruction, to overcome the poor vascularity due to periurethral scarred tissue and limitation of the choice of local flap, we report our experience with one-stage reconstruction of urethral defect using a longitudinal tubed flap of scrotal skin. Methods: A 72-year-old man with several years of diabetes mellitus history visited for swelling and pain of scrotal area. After diagnosis of Fournier's Gangrene, radical debridement was performed and 6 cm of urethral defect on border of penile-scrotal ventral area was made. Rectangular scrotal skin flap ($6{\times}2.5\;cm$) based on external spermatic fascia was elevated and tubed longitudinally. After transfer the flap to the defect area, end-to-end anastomosis was performed bilaterally. Results: 4 weeks after the operation, the patient started voiding him-self and urethrography showed good fluence of contrast agent. Long term evaluation reveals stable performance characteristics without any complications. Conclusion: We suggest a one-stage reconstruction of extensive urethral defect using a longitudinal tubed flap of scrotal skin. Advantages of this procedures are simple, one-stage reconstruction with the reliable scrotal skin flap based on external spermatic fascial vasculature, and no donor morbidity.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.1
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• pp.83-88
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• 2011

The goal of this treatment is the surgical-orthodontic eruption of impacted permanent teeth associated with a large dentigerous cyst in a preadolescent patient. Although enucleation of the entire cyst and the extraction of impacted teeth are common treatments, missing permanent teeth cause several problems in young patients. In this report, an 11-year-old female visited with the chief complaint of a large radiolucent lesion from the mandibular anterior area to the left mandibular posterior area. The permanent left canine and premolars were displaced toward the mandibular inferior border area. The extraction of infected deciduous teeth and marsupialization were performed. After 4 months, orthodontic buttons for forced eruption were applied to the impacted permanent teeth. The teeth emerged into the oral cavity 3 months after the orthodontic treatment. Although the root form was abnormal, there were no other pathogenic signs. The alveolar bone had a normal trabecular pattern and the teeth appeared to be well maintained at postoperative 24 months.