• Journal of the Korean Ceramic Society
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• v.39 no.9
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• pp.890-895
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• 2002

Effect of the sintering time on the microwave dielectric properties of the layered Functionally Graded Materials(FGMs) of the Mg0.93Ca0.07TiO3(MCT) with (Ca0.3Li0.14Sm0.42)TiO3(CLST) ceramics was investigated. The dielectric constant of layered FGMs specimens showed a nearly constant value and did not change significantly with sintering time. The quality factor, however, was affected by the relative density and thermal stress developed in each dielectric layer. With an increase of the relative density and the decrease of the induced thermal stresses, quality factor of the layered FGMs specimens increased and the quality factor was incluenced sensitively by the change of compressive stress developed in MCT layers which had a lower thermal expansion coefficient than that of CLST. For the layered FGMs specimen sintered at 1300$^{\circ}C$ for 9h, the compressive stress developed in MCT layer showed the maximum value, which, in turn, the quality factor of the specimen was the minimum value.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.300-307
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• 2010

Greenhouse experiment was conducted to evaluate tolerance of six rice cultivars, three Indica${\times}$Japonica rice (long grain, cv. Dasanbyeo, Segejinmi and Hanareumbyeo) and three Japonica rice (short grain, Nampyung, Ilpumbyeo and Junamjosaeng) cultivars, to mesotrione+pretilachlor (MP) and bensulfuron-methyl+mesotrione+pretilachlor+pyriftalid (BMPP) in transplanting rice. Two herbicides were applied at 90 g and 180 g a.i. $ha^{-1}$ to three to four leaf stage rice at 5 and 15 days after transplanting, respectively. Related study was also conducted to compare $GR_{50}$ for Indica${\times}$Japonica and Japonica rice cultivars at different MP rates. Response to two herbicides varied with respect to rice cultivars and herbicide rates. All Indica${\times}$Japonica rice cultivars exhibited susceptible to both MP and BMPP as reflected by increased visual injury, shorter plant height and higher plant dry matter reduction when compared with nontreated rice cutlivars. The degree of foliar chlorosis by MP at 90 g a.i. $ha^{-1}$ was 5~6 at 7 days after treatment(DAT) but it was decreased to 3~6 at 14DAT. The degree of leaf chlorosis treated with 180 g a.i. $ha^{-1}$ MP was 6~7 at 7DAT and it was also decreased to 3~8 at 14 DAT. The plant hight of Indica${\times}$Japonica rices was inhibited by 18~43% at application of 90 g a.i. $ha^{-1}$ MP and 30~50% at 180 g a.i. $ha^{-1}$ MP. The dry matter reduction was greater than that of plant height inhibition, showing 46~73% at 90 g a.i. $ha^{-1}$ MP and 65~82% at 180 g a.i. $ha^{-1}$ MP. Similar leaf chlorosis injury and growth inhibition of rice cultivars was observed in the BMPP treatment. The injury and growth inhibition by MP and BMPP increased with increase in herbicide rate from 90 g a.i. $ha^{-1}$ to 180 g a.i. $ha^{-1}$. However, most of the Japonica cultivars are tolerant to MP and BMPP at both rates. There was no visible leaf chlorosis but plant height and dry matter production were slightly reduced at 180 g a.i. $ha^{-1}$. Based on $GR_{50}$ value determined in reduction of shoot dry weight for MP, the Indica${\times}$Japonica rice showed 12.9 fold lower compared with the Japonica rice. The result indicates that rice cultivars vary in tolerance to herbicides of MP and BMPP and Indica${\times}$Japonica rices were more susceptible than the Japonica rices to the MP and BMPP.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.1
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• pp.61-69
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• 2008

Purpose: Micro-pinhole SPECT system with conventional multiple-head gamma cameras has the advantage of high magnification factor for imaging of rodents. However, several geometric factors should be calibrated to obtain the SPECT image with good image quality. We developed a simplified geometric calibration method for rotating triple-head pinhole SPECT system and assessed the effects of the calibration using several phantom and rodent imaging studies. Materials and Methods: Trionix Triad XLT9 triple-head SPECT scanner with 1.0 mm pinhole apertures were used for the experiments. Approximately centered point source was scanned to track the angle-dependent positioning errors. The centroid of point source was determined by the center of mass calculation. Axially departed two point sources were scanned to calibrate radius of rotation from pinhole to center of rotation. To verify the improvements by the geometric calibration, we compared the spatial resolution of the reconstructed image of Tc-99m point source with and without the calibration. SPECT image of micro performance phantom with hot rod inserts was acquired and several animal imaging studies were performed. Results: Exact sphere shape of the point source was obtained by applying the calibration and axial resolution was improved. Lesion detectibility and image quality was also much improved by the calibration in the phantom and animal studies. Conclusion: Serious degradation of micro-pinhole SPECT images due to the geometric errors could be corrected using a simplified calibration method using only one or two point sources.

• Journal of Korean Society of Transportation
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• v.27 no.2
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• pp.23-34
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• 2009

This paper is described as an experimental analysis for the probabilistic directional design hour volume estimation. The main objective of this paper is to derive acceptable design rankings, PK factors, and PD factors. In order to determine an appropriate distribution for acceptable design rankings, 12 probability distribution functions were employed. The parameters were estimated based on the method of maximum likelihood. The goodness of fit test was performed with a Kolmogorov-Smirnov test. The Beta General distribution among the probability distributions was selected as an appropriate model for 2 lane roadways. On the other hand, the Weibull distribution is superior for 4 lanes. The method of the inverse cumulative distribution function came up with an acceptable design ranking of design for LOS D. An acceptable design ranking of 2 lanes is 190, while an acceptable design ranking for 4 lanes is 164. The PK factor and PD factor of 2 lanes was elicited for 0.119 (0.100-0.139) and 0.568 (0.545-0.590), respectively. On the other hand, the PK factor and PD factor for 4 lanes was elicited as 0.106 (0.097-0.114) and 0.571 (0.544-0.598), respectively.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.271-277
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• 1996

In selected cases, early corrective surgery is indicated in the management of infants having large ventricular septal defects. The risk of any surgical procedure in infancy is acknowledged to be great and should be avoided whenever possible. However this greater surgical risk is justified when the patient presents with intractable congestive heart failure, severe pulmonary hypertension, marked growth retardation, and recurrent prolonged lower respiratory infections. We analyzed 31 patients with ventricular septal defect in infancy who underwent surgical correction from January 1991 through December 1994. Age ranged from 6 months to 12 months with mean age of 9.2 months. Of the thirty-one patients, 23 patients were male and 8 patients were female. Mean body weight was 7. 4kg. The most common type of ventricular septal defect was perimembraneo s (64.5%). Associated cardiac anomalies were found in 17 patients (55.8%). Mitral regurgitation was the most commonly associated cardiac anomaly (16.1 %) and followed by patent ductus arteriosus (12.9%). When cardiac catheterization data were analysed, the most common range of Qp/qs, RpiRs, Pp/ps were 2.1∼ 3.0, 1-0.25, above 0.70 respectively. Among the indications of surgical correction, there were pulmonary hypertension in 20 patients, congestive heart failure in 3 patients, intractable respiratory infection in 10 patients and growth retardation in 14 patients. The most common surgical approach and method for closure of ventricular septal defect .were right atriotomy (58%) and Dacron patch closure (94%). Postoperative complications occurred in 10 cases (32%) and overall mortality was 12.9% (4 cases). All operative deaths in this series occurred in infants under the age of 8 months and weight of 8 kilograms.

• Journal of Chest Surgery
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• v.39 no.1 s.258
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• pp.12-17
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• 2006

Background: Circulatory arrest under deep hypothermia is an important auxiliary means for surgical correction of total anomalous pulmonary venous connection (TAPVC), However, cardiac operations under deep hypothermic circulatory arrest are associated with the risk of post-arrest neurologic abnormalities. The purpose of this study is to evaluate the results of the surgical correction of total anomalous pulmonary venous connection without the total circulatory arrest. Materiai and Method: Between April 2000 and October 2004, hospital records of 10 patients were reviewed retrospectively. Result: The locations for abnormal anatomical connections were supracardiac in 7 cases, cardiac in 1 case, and infracardiac in 2 cases. The mean cardiopulmonary bypass time and aorta cross clamp time were 116.8$\pm$40.7 and 69.5$\pm$24.1 minutes. There was no surgical mortality. Postoperative complications were post-repair pulmonary venous stenosis in 1 case, pneumonia in 1, pneumothorax in 1, wound infection in 1,and diaphragmatic paralysis in 1. All patients without pulmonary venous stenosis were in NYHA class I at mean follow-up of 16.6 months (3$\∼$49 months) Conclusion: We could obtain excellent results by repair without the total circulatory arrest for total anomalous pulmonary venous connection.

• Journal of the Korea Computer Graphics Society
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• v.26 no.3
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• pp.111-121
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• 2020

Realistic training contents utilizing intensive immersion of virtual reality are being used in various fields such as industry, education, and medical care. High-risk, high-cost education training, in particular, is difficult to conduct in reality, but it can be applied with the latest virtual reality technology that enhances educational effectiveness by efficiently and safely experiencing it in an environment similar to reality. This study introduces a management system that systematically manages realistic virtual training contents and visualizes training results in schematic pictures based on defined evaluation elements. The management system can store the information generated from the content in the database and manage the training records of each trainee in a practical way. In addition, a content-based scenario can be created in multiple scenarios by setting training goals, number of participants, and methods for applying evaluation elements. This paper describes the management system's production method and the results based on the virtual reality training content as an application example.

• Journal of Broadcast Engineering
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• v.10 no.3
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• pp.422-435
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• 2005

Compared with analog broadcasting, digital broadcasting supports technical background to provide personalize the TV watching environment by offering broadcasting services that can adapt to viewers' preferences. However, current digital broadcasting shows limited services such as reservation recording, simple program guiding with an electronic program guide (EPG) on a personal video recorder system, and primitive data broadcasting by broadcasters. Therefore, the purpose of this paper is to suggest a new broadcasting environment which gives a person facility and a difference fur watching TV by serving enhanced personalized services. For that reason, we propose an intelligent broadcasting system which can minimize viewer's actions, and enhanced broadcasting services which are based on understanding of the semantics of broadcasting contents. To implement the system, agent technology as well as the MPEG-7 and TV-Anytime Forum (TVAF) are employed. For content-level services, real-time content filtering and personalized video skimming are designed and implemented. To verify the usefulness of the proposed system, we demonstrate it with a test-bed on which content-level personalized services are implemented.

• The Journal of the Korea Contents Association
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• v.19 no.1
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• pp.660-670
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• 2019

The purpose of this study is to elaborate the logical configuration of livelihood benefits for the institutionalized recipients under the renewed custom-tailored benefit system of National Basic Livelihood Security System(NBLSS) and to present appropriate level of benefits in terms of coherency of the system. In July 2015, the NBLSS was reformed to adopt a relative level of benefit standard for the general recipients according to certain amount of ratio of standard median income. However, the benefit for the institutionalized recipients was still based on the cost of necessities of absolute poverty level. It is at this juncture that this study suggests livelihood benefits for the institutionalized recipients reflect standard median income to comply with the reform of the NBLSS. To this end, this study firstly derives basic living items for the institutionalized recipients based on the literature review and FGI. Secondly, it calculates the reflection ratio of livelihood benefits utilizing Household Trend Survey's consumption data under 40%. Finally, it applies equivalence scale of households to adjust the under-represented scale for large size institutions. To continue the reflection ratio method, it is necessary to review the consumption trends and the stability of the reflection ratio periodically.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.522-528
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• 2018

Saemimyeon, a Tongil type, medium-late maturing rice variety, is especially used for preparing rice noodles. Its high amylose content was developed to fit market demands and to be affordable for rice processing industries. One of the high yielding lines, Milyang181 (Hanareum), was used in the final three-way cross of $IR50^*2$/YR18241-B-B-115-1-1 for yield improvement and cultivation stabilization, including disease resistance. YR24235-10-1-3, a high yielding and compact plant type, was selected and named Milyang278 after yield test at NICS (RDA, Miryang) in 2010. It was subjected to regional yield test at six sites in the middle and southern plain areas of South Korea. Saemimyeon heading occurs on August 12 and is a mid-late maturing cultivar, with resistance to leaf blast, rice stripe virus, and bacterial blight (K1-K3a), but it is susceptible to major diseases and insect pest infestation. Saemimyeon showed a high amylose content of 26.7%, with a relatively low KOH digestion value of 3.5, which are key factors in rice noodles and pasta processing. In the local adaptability tests, the yield of Saemimyeon was 7.08 MT/ha-an increase of approximately 106% compared to that of Dasan. Thus, Saemimyeon is suitable for cultivation in the southern and middle plain areas of South Korea.