• Journal of radiological science and technology
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• v.31 no.4
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• pp.401-406
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• 2008

The aim of this study is to evaluate contra-lateral breast (CLB) surface dose in Field-in-Field (FIF) technique for breast conserving surgery patients. For evaluation of surface dose in FIF technique, we have compared with other techniques, which were open fields (Open), metal wedge (MW), and enhanced dynamic wedge (EDW) techniques under same geometrical condition and prescribed dose. The three dimensional treatment planning system was used for dose optimization. For the verification of dose calculation, measurements using MOSFET detectors with Anderson Rando phantom were performed. The measured points for four different techniques were at the depth of 0cm (epidermis) and 0.5cm bolus (dermis), and spacing toward 2cm, 4cm, 6cm, 8cm, 10cm apart from the edge of tangential medial beam. The dose calculations were done in 0.25cm grid resolution by modified Batho method for inhomogeneity correction. In the planning results, the surface doses were differentiated in the range of $19.6{\sim}36.9%$, $33.2{\sim}138.2%$ for MW, $1.0{\sim}7.9%$, $1.6{\sim}37.4%$ for EDW, and for FIF at the depth of epidermis and dermis as compared to Open respectively. In the measurements, the surface doses were differentiated in the range of $11.1{\sim}71%$, $22.9{\sim}161%$ for MW, $4.1{\sim}15.5%$, $8.2{\sim}37.9%$ for EDW, and 4.9% for FIF at the depth of epidermis and dermis as compared to Open respectively. The surface doses were considered as underestimating in the planning calculation as compared to the measurement with MOSFET detectors. Was concluded as the lowest one among the techniques, even if it was compared with Open method. Our conclusion could be stated that the FIF technique could make the optimum dose distribution in Breast target, while effectively reduce the probability of secondary carcinogenesis due to undesirable scattered radiation to contra-lateral breast.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.2
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• pp.114-128
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• 2013

Rapid industrialization and economic growth have led to serious problems including reduced open space, environmental degradation, traffic congestion, and urban sprawl. These problems have been exacerbated by the absence of effective conservation and governance, and have resulted in various social conflicts. In response to these challenges, many scholar and government hope to achieve sustainable development through the establishment and management of environment-friendly planning. For this purpose, we would like to analyze functional change for ecosystem by future land-use/cover changes in South Korea. Toward this goal, we predicted land-use/cover changes from 2010 to 2060 using the future population of Statistics Korea and urban growth probability map created by logistic regression analysis and analyzed ecosystem service value using costanza's coefficient. In the case of scenario 1, ecosystem service value represented 6,783~7,092 million USD. In the case of scenario 2, ecosystem represented 6,775~7,089 million USD, 2.9~7.6 million USD decreased compared by scenario 1. This was the result of area reduction for farmland and wetland which have high environmental value relatively according to urban growth by development point of view. The results of this analysis indicate that environmentally sustainable systems and urban development must be applied to achieve sustainable development and environmental protection. Quantitative analysis of environmental values in accordance with environmental policy can help inform the decisions of policy makers and urban developers. Furthermore, forecasting urban growth based on future demand will provide more precise predictive analysis.

• Journal of Gifted/Talented Education
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• v.25 no.6
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• pp.817-836
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• 2015

This research focuses on the development of gifted child behavior checklist which feasibly has application on the nation-wide gifted children observation-recommendation method. Corresponding measure has significance as it reflects actual observations of teachers teaching gifted children first-hand and involves measure of importance regarding each characteristic. An open survey on gifted children behavior characteristics lists and specific behavior patterns has been acquired from teachers in gifted education, and the checklist was developed through expert group review, pre-test, and confirmatory factor analysis process. The former checklists have shown several difficulties on application of observation-recommendation on the field due to behaviors that can't be observed in school, less important behaviors, and collide and duplicate behaviors etc. With regard to such problems, problematic clauses were removed based on the observation probability and importance of the behaviors. Ultimately, total of 32 behavior characteristic checklist consisting of ten sub factors(logical thinking, high achievement, originality, perfectionism, creative problem solving, curiosity, task commitment, conversation ability, creativity, passion) and two to three questions on each factor had been drawn. Through internal consistency test and item-total score correlation, each item of the measure has been analyzed to be consistently evaluating corresponding variables. In addition, the result of confirmatory factor analysis showed every item to be weighed appropriately on its sub-factor, strongly suggesting its feasibility on observation-recommendation of elementary gifted children as an appropriate checklist.

• Nuclear Engineering and Technology
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• v.11 no.4
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• pp.263-274
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• 1979

A statistical approach is used to investigate the relative economic advantages of pressurized water reactor (PWR) and pressurized heavy water reactor (PHWR-CANDU) nuclear power plants for hypothetical 900Mwe systems with the throwaway fuel cycle to be built in the Republic of Korea. Power cost is decomposed into the cost components related to the plant capital, operation and maintenance, working capital requirements and fuel cycle operation. The calculation of construction cost is performed with the modified version of computer code ORCOST, and the modified POWERCO-50 is used to evaluate the cost components. Most of economic parameters are treated as statistical variables, each being given with a certain range. Through a random sampling procedures. the probability histograms on unit plant construction costs and power generating costs are obtained. The power cost probability histograms of the PWR and the PHWR plants overlap considerably, and the power costs of two systems appear to be almost same with the PHWR power cost being 0.4mil1/kwh lower compared with 39.4 mills/kwh for the PWR plant (July 1986 US-dollars). When a construction period of PHWR plant is longer by one year than that of PWR plant, there is no difference in the unit power cost of two plants. This comparison leads to no definite conclusion on the cost advantage of the PWR plant versus the PHWR plant. We conclude that the selection issue of nuclear power plants in Korea still remains an open question and that future effort to solve this question should be made toward economic quantification of those factors such as technology transfer and localization.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.3
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• pp.203-208
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• 2007

The woody tissue respiration rates in stems ($R_{stem}$) of red pine (Pinus densiflora Sieb. et Zucc.) forest in Higashi-Hiroshima, west Japan, were measured using an open flow measurement system with several chambers in two seasons (the winter and summer in 2002). $R_{stem}$ ranged from 0.25 to $0.55{\mu}mol\;m^{-2}s^{-1}$ in winter, and from 1.25 to $1.63{\mu}mol\;m^{-2}s^{-1}$ in summer. The variability of $R_{stem}$ among the sampled trees (n=15) was similar between the two seasons, with the coefficient variation of about 23%. The numbers of sampling points required to estimate the stem respiration rate within 10 to 20% of its actual value were 24 and 6, respectively in both seasons (probability level is 95%). Based on the relationship between stem temperature and average $R_{stem}$ the $Q_{10}$ values of the winter and summer seasons were 1.49 and 1.45, respectively. The $R_{20}$($R_{stem}$ at $20^{\circ}C$ of stem temperature) was higher in summer ($1.23{\mu}mol\;m^{-2}s^{-1}$) than winter ($0.61{\mu}mol\;m^{-2}s^{-1}$). The woody tissue respiration in stems of red pine trees during the summer season amounted about 50% of the total respiration rates.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.2
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• pp.157-161
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• 2004

The eyes, the saying goes, are the windows of the soul. It's the first thing you notice about a person. Therefore, many people want to possess beautiful eyelids. Surgical formation of a palpebral fold and sulcus divides the lid into two well-defined segments (palpebral and pretarsal), producing the double eyelid desired by many Oriental women as well as an increasing number of man recently. Upper lid blepharoplasty is the Oriental eye is one of the variations of standard upper lid blepharoplasty. In Oriental double eyelid surgery, there have been two approaches to form a superior palpebral fold: the buried suture(nonincision) method and the full external incision method. Conventionally, the nonincision technique has been shown to produce little postoperative edema. However, the probability of the fold disappearing is high, and this technique cannot be performed in patients with fatty eyelids. Conversely, the incision technique has contrary characteristics. Recently, partial incision(or semi-open) technique which is combination of mentioned methods is used, this technique is removal of pretarsal tissue, muscle, and/or orbital fat around 2 or 3 incision site to facilitate tarsus-dermal adhesion. Our method is on the basis of this technique, furthermore, compared with conventional semi-open method, Y(Yang's) needle assisted double eyelid operation is more easy, convenient, saving-time method and provide satisfactory results.

• Journal of Internet Computing and Services
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• v.16 no.1
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• pp.21-28
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• 2015

Currently there are wide variety of web services and applications available for users. Such services restrict access to only authorized users, and therefore its users often need to go through the inconvenience of getting an authentication from each service every time. To resolve of such inconvenience, a third party application with OAuth(Open Authorization) protocol that can provide restricted access to different web services has appeared. OAuth protocol provides applicable and flexible services to its users, but is exposed to reply attack, phishing attack, impersonation attack. Therefore we propose method that after authentication Access Token can be issued by using the E-mail authentication. In proposed method, regular user authentication success rate is high when value is 5 minutes. However, in the case of the attacker, the probability which can be gotten certificated is not more than the user contrast 0.3% within 5 minutes.

• The Transactions of the Korea Information Processing Society
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• v.4 no.7
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• pp.1804-1820
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• 1997

In this paper, an efficient call control procedure is presented for next generation wireless ATM networks and its performance is mathematically analyzed using the open queueing network. This procedure is based on a new scheme called as the cell clustering. When we use the cell clustering scheme, at the time that a mobile connection is admitted to the network, a virtual cell is constructed by choosing a group of neighboring base stations to which the call may probabilistically hand over and by assigning to the call a collection of virtual paths between the base stations. Within a microcell/picocell environment, it is seen that the cell clustering can support effectively a very high rate of handovers, provides very high system capacity, and guarantees a high degree of frequency reuse over the same geographical region without requiring the intervention of the network call control processor each time a handover occurs. But since mobiles, once admitted, are free to roam within the virtual cell, overload condition occurs in which the number of calls to be handled by one base station to exceed that cell site's capacity of radio channel. When an overload condition happens, the quality of service is abruptly degraded. We refer to this as the overload state and in order to quantify the degree of degradation we define two metrics, the probability of overload and the normalized average time spent in the overload state. By using the open network queueing model, we derive closed form expressions for the maximum number of calls that can be admitted into the virtual cell such that the two defined metrics are used as the acceptance criteria for call admission control.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.1
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• pp.161-171
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• 2014

When the Hough transform is applied to identify an instance of a given model, the output is typically a histogram of votes cast by a set of image features into a parameter space. The next step is to threshold the histogram of counts to hypothesize a given match. The question is "What is a reasonable choice of the threshold?" In a standard implementation of the Hough transform, the threshold is selected heuristically, e.g., some fraction of the highest cell count. Setting the threshold too low can give rise to a false alarm of a given shape(Type I error). On the other hand, setting the threshold too high can result in mis-detection of a given shape(Type II error). In this paper, we derive two conditional probability functions of cell counts in the accumulator array of the generalized Hough transform(GHough), that can be used to select a scientific threshold at the peak detection stage of the Ghough.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.1
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• pp.127-133
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• 2020

This paper deals with the development of a smart mirror to support changing hair styles. A key function of the service is the ability to synthesize the image into the user's face when the user chooses a desired hair image and virtually styling the hair. To check the effectiveness of the hair image synthesis function, the success rate measurement experiment of Haar-cascade algorithm's facial recognition was conducted. Experiments have confirmed that the facial recognition succeeds with a 95 percent probability, with both eyes and eyebrows visible to the subjects. It is the highest success rate. It confirmed that if either of the eyebrows of the subjects are not visible or one eyeball is covered, the success rate of facial recognition is 50% and 0% respectively.