• Geophysics and Geophysical Exploration
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• v.2 no.2
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• pp.77-85
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• 1999

The 3-D seismic research vessel, Tamhae II, was built to raise up the probability of the hydrocarbon discovery in the Korean continental shelf and the first test survey was completed in the East Sea. During the survey, the 240 channel 2-D marine seismic data were acquired by the Korean flag vessel for the first time. Tamhae II has been equipped with source, receiver, recording equipment, and navigation equipment as well as an onboard processing system. The source is composed of four subarrays and each subarray has six airguns. Total airgun volume is 4578 $in^3$. The receiver consists of two sets of 3 km long 240 channel streamer. In the first survey, the successful acquisition of 2-D seismic data was accomplished. From the result of the data processing, we confirmed that the high quality seismic data were acquired. For the high quality data acquisition, technology of survey design and planning, operation of vessel and equipments and systematic quality control should be developed.

• Korea Journal of Hospital Management
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• v.13 no.4
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• pp.27-45
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• 2008

This research focused on a total of 378 patients with external injuries under the age of 14 who visited the emergency center at a university hospital in Korea, during the months of January, April, August and November between January and December of 2007. In addition, the survey was conducted only on even number days and ranged across the whole year to reflect the impact of seasonal characteristics on the collected data. The research focused on determining the characteristics and inflicting cause of these patients with external injuries, analyzed the total time spent in the emergency room and obtained the following results. 1. When classifying the patients into different genders, the proportion of males (67.5%) was higher than that of females (32.5%). According to the different age groups, the highest ratio, at 61.1 %, was patients under the age of six. 2. Looking at the total number of minutes spent in the emergency room, the longest amount of time occurred during April with 162.7 minutes, followed by 121.9 minutes in January and 92.4 minutes in November. August had the shortest period of time spent in the emergency room, a significant statistical difference from the other periods of the year (p<0.001). 3. Regarding the amount of time required for each examination, patients required to provide a urine test spent an average of 204.7 minutes while those who did not spent 113.5 minutes on average. This is a 5% statistical difference among the two groups (p>0.05). 4. Looking at the five most commonly diagnosed problems in the emergency room, the total number of people with these top five commonly diagnosed illnesses comprised 55.6%, or 210 patients out of 378. 5. Utilizing the Decision Tree Model to estimate the total number of minutes required per visit, the first classifications were made using a chemical examination factor. People subject to chemical classification spent an average of 177.7 minutes, which was longer than the overall average of 115.2 minutes, and those exempt from chemical examination spent an average of 103.8 minutes, which was shorter than the average Conclusion; Effort to curtail the total time spent in emergency rooms is vital in guaranteeing efficient management of hospitals and providing medical services. The delay experienced by many comprehensive professional medical centers must be resolved through the establishment of effective delivery of medical services, increased supply of patient rooms and other policy oriented implementations. However, for now, this problem must be resolved by increasing the level of patient satisfaction and guaranteeing effective operation of patient rooms, which will significantly contribute to the general management and success of hospitals and institutions.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.3
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• pp.421-432
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• 2020

This paper proposes a 2-kW solid-state power amplifier (SSPA) developed by employing power amplifier pallets designed using gallium-nitride high electron mobility transistors, which is used in S-band military radars and to replace existing traveling-wave tube amplifier (TWTA). The SSPA consists of a high-power amplifier module, which combines eight power amplifier pallets, a drive amplifier module, a digital control module, and a power supply unit. First, the amplifier module and component were integrated into a small package to account for space limitations; next, an on-board harmonic filter was fabricated to reject spurious components; and finally, an auto gain control system was designed for various duty ratios because recent military radar systems are all active phase radars using the pulse operation mode. The developed SSPA exhibited a max gain of 48 dB and an output power ranging between 63-63.6 dBm at a frequency band of 3.1 to 3.5 GHz. The auto gain control function showed that the output power is regulated around 63 dBm despite the fluctuation of the input power from 15-20 dBm. Finally, reliability of the developed system was verified through a temperature environment test for nine hours at high (55 ℃) / low (-40℃) temperature profile in accordance with military standard 810. The developed SSPA show better performance such as light weight, high output, high gain, various safety function, low repair cost and short repair time than existing TWTA.

• Journal of the Korea Computer Graphics Society
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• v.26 no.1
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• pp.17-25
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• 2020

We present a novel multi-core CPU based parallel algorithm for the cell-connectivity information extraction algorithm, which is one of the preprocessing steps for volume rendering of unstructured grid data. We first check the synchronization issues when parallelizing the prior serial algorithm naively. Then, we propose a 3-step parallel algorithm that achieves high parallelization efficiency by removing synchronization in each step. Also, our 3-step algorithm improves the cache utilization efficiency by increasing the spatial locality for the duplicated triangle test process, which is the core operation of building cell-connectivity information. We further improve the efficiency of our parallel algorithm by employing a memory pool for each thread. To check the benefit of our approach, we implemented our method on a system consisting of two octa-core CPUs and measured the performance. As a result, our method shows continuous performance improvement as we add threads. Also, it achieves up to 82.9 times higher performance compared with the prior serial algorithm when we use thirty-two threads (sixteen physical cores). These results demonstrate the high parallelization efficiency and high cache utilization efficiency of our method. Also, it validates the suitability of our algorithm for large-scale unstructured data.

• Journal of Gastric Cancer
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• v.4 no.3
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• pp.137-142
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• 2004

Purpose: There have been some controversies over the therapeutic principles of advanced gastric cancer, and the results of treatment have been variable, especially for stage III disease. This study was conducted to define the prognostic factors of stage III gastric cancer. Materials and Methods: This retrospective study was based on the medical records of 179 patients with stage III disease who received a gastrectomy from January 1990 to December 1994. The 5-year survival rate was analyzed according to the age, sex, tumor location, tumor size, Borrmann's type, depth of invasion, lymph-node metastasis, ratio of metastatic lymph nodes, type of surgical resection, extent of lymphnode dissection, curability of resection, postoperative chemotherapy, and pathological stage. The statistical analysis was done by using the Kaplan-Meier method, the log-rank test, and the Cox proportional hazards model. Results: The overall 5-year survival rate was $61.6\%$ the 5-year survival rates according to subgroup were $69.7\%$ for stage IIIa ($100\%$ for $T_{2}N_{2}$, $70.0\%$ for $T_{3}N_{1}$, $68.6\%$ for $T_{4}N_{0}$), and $54.1\%$ for stage IIIb ($T_{3}N_{2}$) (P<0.05). Among various clinicopathologic factors of stage III gastric cancer, the age of the patient, the tumor location, the gross type of tumor, the type of gastric resection, the extent of lymph-node dissection, the curability of resection, and the subgroups of stage III were statistically significant in the univariate survival analysis. The multivariate analysis defined the curability of resection, the extent of lymph-node dissection, the type of operation, the stage of disease, and the age of the patient as independent prognostic factors. Conclusion: A curative surgical resection and an extended lymph-node dissection are thought to be most important for improving the survival rate in stage III gastric cancer patients.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1742-1754
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• 1999

In this paper, we propose a rate control scheme, using histogram based rate-distortion (R-D) estimation, which produces a consistent picture quality between consecutive frames. The histogram based R-D estimation used in our rate control scheme offers a closed-form mathematical model that enable us to predict the bits and the distortion generated from an encoded frame at a given quantization parameter (QP) and vice versa. The most attractive feature of the R-D estimation is low complexity of computing the R-D data because its major operation is just to obtain a histogram or weighted histogram of DCT coefficients from an input picture. Furthermore, it is accurate enough to be applied to the practical video coding. Therefore, the proposed rate control scheme using this R-D estimation model is appropriate for the applications requiring low delay and low complexity, and controls the output bit-rate ad quality accurately. Our rate control scheme ensures that the video buffer do not underflow and overflow by satisfying the buffer constraint and, additionally, prevents quality difference between consecutive frames from exceeding certain level by adopting the distortion constraint. In addition, a consistent considering the maximum tolerance BER of the voice service. Also in Rician fading channel of K=6 and K=10, considering CLP=$10^{-3}$ as a criterion, it is observed that the performance improment of about 3.5 dB and 1.5 dB is obtained, respectively, in terms of $E_b$/$N_o$ by employing the concatenated FEC code with pilot symbols.

• Journal of The Korean Association of Information Education
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• v.11 no.3
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• pp.339-347
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• 2007

Along with developments of information and communication technologies, internet has spread not only all over the society, but also our everyday life deeply. Recently, requirements for e-learning using internet in the educational aspect have a great influence on the changes of school educations. Cyber Home Learning System, in particular, has been implemented throughout the nation for the purpose of reducing private expenditure for education and promoting substantial improvements in quality of public education. However, there have been exposed many problems with respect to quality of operations and managements of the system comparing to its quantitative growth, and so, at this point in time, researcher conducted analysis of actuality of perceptions of both elementary and middle school teachers with a focus on the case of S System in K province. To test this, total 278 participants were sampled from the elementary schools (139 teachers) and the middle schools (139 teachers) located in K province and were asked to complete a survey and the results therefrom were analyzed accordingly. Results from the analyses revealed that elementary school teachers responded more positively than other respondents in the most areas, including supply of a variety of learning contents of S System, quality of contents, and providing for helps insomuch as to complement school works, etcetera. In addition, researcher has found out that, to make the system become all the more efficient, it shall be required to establish a strategy in order to induce students' interest in the system, as well as to construct infrastructure for facilitating the use of computer. And that there are also needs for continuous supports from both the school and the education authority concerned, and for method of flexible operation of curriculum.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.6
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• pp.490-496
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• 2011

Purpose: Dr. Marquardt made the facial 'phi' mask using golden ratio. Most class III patients have bulky faces and want a smaller face. Using a facial golden mask, this study estimated and compared frontal photographs before and after operation for soft tissue measurement. The golden mask can be considered as a reference tool for facial esthetic analyses especially in lower face. Methods: Forty patients who had undergone orthognathic surgery at Samsung Medical Center from January 2006 to December 2009 were included in this study. These patients had Class III malocclusion. Lateral cephalometric radiographs, frontal clinical photos of pre-op and 8~12 month later post-op, and the facial 'phi' mask using golden ratio, were used for analysis. Reduction of the lower face area, occlusal plane changes, amounts of mandible setback and amounts of maxilla posterior impaction were estimated. Results: Lower facial reduction ratio and mandibular setback amounts were significantly different between 1-jaw and 2-jaw groups. Average postoperative changes in the area of lower face between bilateral sagittal split ramus osteotomy (BSSRO) and BSSRO combined maxilla posterior impaction were compared by using an independent simple t-test and $P$ value was 0.016. Therefore, the lower facial reduction ratio and mandibular setback amount were significantly different in maxilla posterior impaction. Conclusion: The two-jaw surgery group showed more reduction of the lower facial area than the 1-jaw surgery group. The amount of lower facial reduction was more related with the amount of mandibular setback. There was no significant relation in lower facial reduction with amount of maxilla posterior impaction, pre-op occlusal plane, post-op occlusal plane and the mandibular angle. A relationship between the change in the lower facial area and the amount of maxilla posterior impaction or the change of mandibular angle occlusal plane at pre-op could not be found because of the difference in the amount of setback between two groups.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.129-138
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• 2014

This paper proposes a fast intra prediction method to reduce encoding time for the HEVC(high-efficiency video coding) encoder. The proposed fast Intra prediction method uses quadtree structure and SATD(Sum of Absolute Transformed Differences). In HEVC, a $8{\times}8$ SATD value using $8{\times}8$ hadamard transform is used to calculate a SATD value for $8{\times}8$ or larger blocks. The proposed method calculates the best SATD value by using each $8{\times}8$ SATD result in $16{\times}16$ or larger blocks. After that, the proposed method removes a candidate mode for RDO(Rate-Distortion Optimization) based on comparing SATD of the candidate mode and the best SATD. By removing candidate modes, the proposed method reduces the operation of RDO and reduces total encoding time. In $8{\times}8$ block, the proposed method uses additional $4{\times}4$ SATD to calculat the best SATD. The experimental results show that the proposed method achieved 5.08% reduction in encoding time compared to the HEVC test model 12.1 encoder with almost no loss in compression performance.

• Journal of the Korean Society of Costume
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• v.6
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• pp.65-87
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• 1982

1. Purpose: The purpose is to apply and adapt ancient textile pattern to practical life, and to contribute to the promotion of the creative development of modernization and Koreanization of textile pattern by the survey of the extent of taste for the textile pattern existent in Korean costume among costumes. 2. Hypothesis: Textile pattern is in most classical one expressed in fact, but nowadays abstract or geometric one is more exist. Consumers are in most part in forties, and so the taste cannot be ignored. Therefore aesthetic consciousness found Korean costume is more important rather than excessively bold or mordern one. 3. Method and Process: (1) This research is analysed 386 one through college student and parents of a primary or high school. (2) Taste of the pattern is comparisoned and analyzed as age. education, pocket money of the student or an income of a month in home through computer. And the analysis of the statistics research is operation through the Chi-Square Goodness of-Fit-Test. 4. Conclusion: (1) The Korean costume put on mostly party or formal dress, therefore it should be researched as an outdoor dress with traditional costume. (2) The most one is concerned in textile pattern, it's taste is different from color, constitution. Textile industry is developed not only weave pattern, gold-coverning pattern but embroidry pattern, dye pattern, therefore the various side of pattern design should be researched. (3) In Side of form, plant pattern is not only most various but highest in popularity. According to approach nowadays, all of the pattern becomes composition or geometric one with abstract tendency and so from these day pattern is necessary combinationed, researched with our people emotion. (4) The color of textile pattern is choiced individual taste. Through investige, research in various side of the modern taste and our costume, we take growing interest in the color, composition of textile, and should dressed with beauty and grace. (5) In side of size, textile pattern is choiced to individual face and body shape through research on form, color, size of these pattern, we should endeavor to dress well. (6) In side of application, most people is concerned in not only interior ornament but the costume is high. Costume research by some people of the outside and symbol with interior through the pattern analysis is not only very important but also is due to people culture.