• Journal of Radiation Protection and Research
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• v.32 no.1
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• pp.1-8
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• 2007

A model for radiological dose assessment in an urban environment, METRO-K has been developed. Characteristics of the model are as follows ; 1) mathematical structures are simple (i.e. simplified input parameters) and easy to understand due to get the results by analytical methods using experimental and empirical data, 2) complex urban environment can easily be made up using only 5 types of basic surfaces, 3) various remediation measures can be applied to different surfaces by evaluating the exposure doses contributing from each contamination surface. Exposure doses contributing from each contamination surface at a particular location of a receptor were evaluated using the data library of kerma values as a function of gamma energy and contamination surface. A kerma data library was prepared fur 7 representative types of Korean urban buildings by extending those data given for 4 representative types of European urban buildings. Initial input data are daily radionuclide concentration in air and precipitation, and fraction of chemical type. Final outputs are absorbed dose rate in air contributing from the basic surfaces as a function of time following a radionuclide deposition, and exposure dose rate contributing from various surfaces constituting the urban environment at a particular location of a receptor. As the result of a contaminative scenario for an apartment built-up area, exposure dose rates show a distinct difference for surrounding environment as well as locations of a receptor.

• Journal of Korea Port Economic Association
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• v.28 no.3
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• pp.27-44
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• 2012

The offshore wind farm is increasingly attractive as one of future energy sources all over the world. In addition, the capacity of an offshore wind turbine gets larger and its physical characteristics are big and heavy. In this regard, a special port is necessary to assemble, store, and transport the offshore wind systems, supporting to form the offshore wind farms. Thus, this study aims to provide a policy maker which evaluation factors can significantly affect to the optimal site selection of a offshore wind port. For this, Fuzzy-AHP method is applied to capture the relative weights. The results of this study can be summarized as follows. Five criteria in level I was defined such as the accumulation factor, the regional factor, the economic factor, the location factor, and the consortium factor. Of these, the accumulation factor(37.4%), the location factor(34.2%), and the economic factor( 24.5%) were analyzed by major factors. In level II, three assessment items of each factor were selected so that total fifteen items were formed. To sum up, the site selection of offshore wind port should consider the density of the wind industry, cargo volume of securing the economic operation of terminals, the development degree of offshore wind related industry, and the proximity to the offshore wind farms. In other words, the construction of offshore wind port should be paid attention to considering not only the proximity to offshore wind farms but also the preference of turbine manufacturing companies.

• The Journal of the Korea Contents Association
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• v.12 no.8
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• pp.59-68
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• 2012

The existing ship monitoring system currently in use has a limitation, which is that it can only identify a boat's location for finding a safe harbor or give an answer to a rescue signal. In addition to this, it is very difficult to add an expensive, more effective monitoring system to small boats because of their small infrastructure in comparison with large boats. Therefore, this study suggests that a new model could be required to better cater to the needs of small boats. The 'Smart Care System', based on location, is better able to monitor the boat and the crew of small boats in comparison with the existing ship monitoring system. Using biomedical data transmission equipment, it is able to survey and send biomedical data so that it can continuously monitor the crew's health. The boat has an intelligent interface device, which has the functions of GPS and attitude sensors, and a web based management system. We have conducted three experiments for the assessment of this system. The experiment of biological data transmission had a success rate of 98 percent, and the tests conducted for recognizing emergency situations also had a 98 percent success rate. In conclusion we confirmed the efficiency of this system.

• Advances in nano research
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• v.9 no.1
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• pp.1-13
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• 2020

In this work, the electrical potential (EP) technique with an artificial neural networks (ANNs) for monitoring of nanostructures are used for the first time. This study employs an expert system to identify size and localize hidden nano-delamination (N.Del) inside layers of nano-pipe (N.P) manufactured from Basalt Fiber Reinforced Polymer (BFRP) laminate composite by using low-cost monitoring method of electrical potential (EP) technique with an artificial neural networks (ANNs), which are combined to decrease detection effort to discern N.Del location/size inside the N.P layers, with high accuracy, simple and low-cost. The dielectric properties of the N.P material are measured before and after N.Del introduced using arrays of electrical contacts and the variation in capacitance values, capacitance change and node potential distribution are analyzed. Using these changes in electrical potential due to N.Del, a finite element (FE) simulation model for N.Del location/size detection is generated by ANSYS and MATLAB, which are combined to simulate sensor characteristic, therefore, FE analyses are employed to make sets of data for the learning of the ANNs. The method is applied for the N.Del monitoring, to minimize the number of FE analysis in order to keep the cost and save the time of the assessment to a minimum. The FE results are in excellent agreement with an ANN and the experimental results available in the literature, thus validating the accuracy and reliability of the proposed technique.

• Journal of Korean Neurosurgical Society
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• v.29 no.1
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• pp.44-50
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• 2000

Objective : A few anecdotal cases of mesenchyme-derived tumors which grow into a cranial cavity have been reported that disclosed a dismal prognosis, due to their critical location, aggressive biological behavior, and high rate of surgical morbidity. The aim of this study is to search clinical factors related to these tumors. Methods : Eight patients who underwent surgical removal of intracranial mesenchymal tumors between January 1993 and December 1997 were studied retrospectively. The tumors included are three chordomas, two chondrosarcomas, two rhabdomyosarcomas, and one hemangiopericytoma. Authors compared clinical features, treatment, and results of our cases with reported cases. The mean follow-up period was 20.5 months. Results : All cases showed nonspecific, location-related clinical findings and arose from sphenopetroclival region. Single stage operation was performed in 4 cases, and skull base approaches in 3 cases. Adjuvant therapies were done in 2 cases. Recurrence was seen in 3 cases(37.5%), and 3 patients died. Interdisciplinary approach with otologic surgeon was done in 2 cases. Conclusion : Recent advancement of refined tactics has made these tumors amenable and provides prolongation of progression-free survival. These are modified skull base approaches, multi-modality treatment options, and inter-disciplinary team approaches. Good results may be expected for these mesenchymal tumors by aggressive resection and adjuvant therapies according to their biological nature.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.41
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• pp.26.1-26.7
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• 2019

Background: The aim of this study was to investigate clinical and pharmacoepidemiologic characteristics of medicationrelated osteonecrosis of the jaw. Methods: The study population is comprised of 86patients who were diagnosed with ONJ at Ewha Womans University Mokdong Hospital from 2008 to 2015. Factors for epidemiologic evaluation were gender, age, location of lesion, and clinical history. The types of bisphosphonates, duration of intake, and the amount of accumulated dose were evaluated for therapeutic response. Clinical symptoms and radiographic images were utilized for the assessment of prognosis. Results: Among the 86 patients, five were male, whereas 81 were female with mean age of 73.98 (range 45-97). Location of the lesion was in the mandible for 58 patients and maxilla in 25 patients. Three patients had both mandible and maxilla affected. This shows that the mandible is more prone to the formation of ONJ lesions compared to the maxilla. ONJ occurred in 38 cases after extraction, nine cases after implant surgery, six cases were denture use, and spontaneously in 33 cases. Seventy-six patients were taking other drugs aside from drugs indicated for osteoporosis. Most of these patients were diagnosed as osteoporosis, rheumatic arthritis, multiple myeloma, or had a history of cancer therapy. Higher weighted total accumulation doses were significantly associated with poorer prognosis (P < 0.05). Conclusion: Dose, duration, route, and relative potency of bisphosphonates are significantly associated with treatment prognosis of osteonecrosis of the jaw.

• Journal of the Korean Dietetic Association
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• v.3 no.1
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• pp.74-89
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• 1997

The aim of this study was to evaluate the foodservice management practices in elementary school in order to provide basic information for an efficient foodservice management. A self completed questionnaire survey of 912 schools in Korea was undertaken. Survey questionnaires consisted of 4 parts including general background, foodservice practices, purchasing practices and the status of cooking facilities and equipments. The main results of the empirical survey were as follows. 1. Elementary schools categorized by location were in urban areas (38.2%), provincial areas (48.0%) and in isolated areas (13.8%). 2. Conventional schools were 72.4% of the total followed by commissary management schools(23.5%) and commissary schools(4.1%). 3. The major factors considered for menu planning were nutritional adequacy(77.4%), preference of children(50.8%), food cost(46.0%), and cooking facilities & equipments in order. 4. The average cost of school lunch in provincial areas was 1494.8$\pm$224.9 won followed by in isolated areas (1337.0$\pm$793.3won) and in large cities (1271.4$\pm$308.1won). The average food cost of lunch was approximately 950won with no significant difference by location of schools. 5. 60% processed food were purchased through retailers in schools located in provincial and isolated areas, whereas 6.6% in schools located in urban areas. Food groups such as meat and its processed food, poultries, fish & shellfish, fruits and vegetables were more purchased through wholesalers in schools located in urban areas than in provincial and isolated areas. 6. Cereals including rice were regularily purchased once a month, whereas of other food items were found to be daily purchased in school located in urban and provincial areas.

• Journal of Gastric Cancer
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• v.1 no.1
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• pp.24-31
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• 2001

Purpose: Despite knowledge of the adverse effects of resection-line disease, surgeons continue to perform inadequate resections. This demonstrates the need for a more aggressive approach to assessment of resection margins at operation. Materials and Methods: Seven hundred fifteen gastric cancer patients who were operated on at our hospital from 1992 to 1998 were included in this analysis. Various clinicopathological factors, including resection-line involvement, were ascertained from the surgical and histopathological records. Results: Of the 715 evaluable patients, 27 patients ($3.8\%$) had involvement of one or both resection lines; in 10 patients the proximal resection line only, in 16 the distal resection line only, and 1 both resection lines were involved. Presence of resection-line involvement was significantly associated with T3 and T4 stage, N (+) stage, M (+) stage, type of operation (total gastrectomy), tumor location (entire stomach), size$\geq$11 cm), and gross type of tumor (Borrmann 4 type). When performing a distal subtotal gastrectomy, no involvement was found when the cranial and caudal distances between the lesion and the line of transection was equal to or greater than 2 cm and 3 cm, respectively, for early cancer and 7 cm and 3 cm, respectively, for advanced cancer. When performing a total gastrectomy for upper 1/3 or middle 1/3 gastric cancer, no involvement was found when the cranial distances between the lesion and the line of transection were equal to or greater than 3 cm and 4 cm, respectively, without distinction of the presence of serosal invasion. Conclusions: The difference in survival between positive and negative margin patients is limited to the group of patients with curative surgery. An important principle of treatment is that the entire tumor must be removed with a 3 cm distal margin and a 2- to 7 cm margin depending on the location and the depth of wall invasion of the tumor, to provide histologically negative margins.

• Archives of Plastic Surgery
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• v.41 no.1
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• pp.57-62
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• 2014

Background Achieving symmetry is a key goal in breast reconstruction. Anatomically shaped tabbed expanders are a new tool in the armamentarium of the breast reconstruction surgeon. Suture tabs allow for full control over the expander position and thus inframammary fold position, and, in theory, tabbed expanders mitigate many factors responsible for poor symmetry. The impact of a tabbed expander on breast symmetry, however, has not been formally reported. This study aims to evaluate breast symmetry following expander-implant reconstruction using tabbed and non-tabbed tissue expanders. Methods A chart review was performed of 188 consecutive expander-implant reconstructions that met the inclusion criteria of adequate follow-up data and postoperative photographs. Demographic, oncologic, postoperative complication, and photographic data was obtained for each patient. The photographic data was scored using a 4-point scale assessing breast symmetry by three blinded, independent reviewers. Results Of the 188 patients, 74 underwent reconstruction with tabbed expanders and 114 with non-tabbed expanders. The tabbed cohort had significantly higher symmetry scores than the non-tabbed cohort ($2.82/4{\pm}0.86$ vs. $2.55/4{\pm}0.92$, P=0.034). Conclusions The use of tabbed tissue expanders improves breast symmetry in tissue expander-implant-based breast reconstruction. Fixation of the expander to the chest wall allows for more precise control over its location and counteracts the day-to-day translational forces that may influence the shape and location of the expander pocket, mitigating many factors responsible for breast asymmetry.

• Korean Journal of Ecology and Environment
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• v.40 no.4
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• pp.527-536
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• 2007

In this study, we applied 10-metric health assessment model, based on the Index of Biological Integrity (IBI) during 2006 in the Changwon Stream, which is located in the Changwon city, Gyeongnam province, S. Korea, and then compared with water quality data. The Index of Biological Integrity (IBI) in the Changwon Stream varied from 18 to 38 in the watershed depending on the sampling location and averaged 30.3 (n=6) during the study. Analysis of tolerance guilds showed that the proportion of sensitive species was 13%, but tolerant and intermediate species were 34% and 53%, respectively. Qualitative Habitat Evaluation Index (QHEI) averaged 43.3 (range: 65-104, n=6) indicating non-supporting condition, based on the criteria of U.S. EPA (1993). Values of QHEI showed a typical longitudinal decreases from the headwater reach to the downstream location, except for Site 1 with a low QHEI value by artificial habitat by concrete construction. Minimum QHEI was found in Site 4 where fish diversity was minimal. Conductivity increased continuously along the gradients and especially showed abrupt increases in the downstream sites along with turbidity. Stream ecosystem health of IBI matched to the values of QHEI except for S6. Low IBI values in the sites 4 and 5 was considered to be a result of combined effects of chemical pollutions and habitat degradations. Our results support the hypotheses of Plafkin et ai. (1989) that physical habitat quality directly influences the trophic structure and species richness, and is closely associated with IBI values.