• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.8
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• pp.1933-1954
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• 2013

Multiple wireless devices are being widely deployed in Intelligent Transportation System (ITS) services on the road to establish end-to-end connection between vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) networks. Vehicular ad hoc networks (VANETs) play an important role in supporting V2V and V2I communications (also called V2X communications) in a variety of urban environments with distinct topological characteristics. In fact, obstacles such as big buildings, moving vehicles, trees, advertisement boards, traffic lights, etc. may block the radio signals in V2X communications. Their impact has been neglected in VANET research. In this paper, we present a realistic and efficient radio propagation model to handle different sizes of static and moving obstacles for V2X communications. In the proposed model, buildings and large moving vehicles are modeled as static and moving obstacles, and taken into account their impact on the packet reception rate, Line-of-sight (LOS) obstruction, and received signal power. We use unsymmetrical city map which has many dead-end roads and open faces. Each dead-end road and open faces are joined to the nearest edge making a polygon to model realistic obstacles. The simulation results of proposed model demonstrates better performance compared to some existing models, that shows proposed model can reflect more realistic simulation environments.

• Journal of Chest Surgery
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• v.24 no.2
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• pp.123-134
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• 1991

Twenty eight patients had undergone repair of an isolated complete atrioventricular septal defect between April 1986 and September 1990 in Seoul National University Children`s Hospital. The group comprised 13 male and 15 female patients. They ranged in age from 2 months to 8 years[mean 18.6months] and in weight from 3. 4kg to 23kg[mean 9.0$\pm$4.6kg]. They were analysed as Rastelli type A in 17 patients, Rastelli type B in 2 patients, and Rastelli type C in 9 patients. Seven patients had concomitant Down`s syndrome. All patients had large left-to-right shunt[mean pulmonary to systemic flow ratio 3.5 $\pm$2.2 ranging from 0.68 to 10.0] and high pulmonary systolic pressure[mean 74$\pm$18.8mmHg, ranging from 35 to 110]. In 11 patients, one patch technique was used to close the atrial and ventricular septal defect and 16 patients were undergone by two patch technique. We urgently managed only one patient by pulmonary artery banding whose anatomy was Rastelli type C and severe mitral regurgitation was identified. Postoperative complete A - V block was noted in 3 patients, two of whom were dead in operating room due to combined LVOTO and myocardial failure, and one patient with Rastelli type C was undergone by VVI type permanent pacemaker insertion 1wk later after two patch technique, but we had to manage him by modified Konno operation and total correction due to LVOTO and VSD leakage and severe mitral regurgitation 3 years later. Another two reoperation cases due to severe mitral regurgitation after two patch technique were undergone, one of whom we managed by mitral annuloplasty 3 months later but aggravated mitral regurgitation made us to control him by MVR 3 months later. Another one case of VSD leakage and tricuspid regurgitation was managed by total correction but she died of respiratory insufficiency 14 days later. We experienced pulmonary hypertensive crisis in 3 patients, who were dead in two cases comparing with one control case. So operative mortality is 9/27[33.6%], in one patch group of 3/11[29.2%] comparing with two patch group of 6/16[37.5%]. In summary, causes of death were pump weaning failure, myocardial failure and low cardiac output syndrome and pulmonary hypertensive crisis, resp. failure, complete AV block. Mean follow up period is 15.8$\pm$10.7 months[ranging from 3months to 37 months]

• Journal of Navigation and Port Research
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• v.30 no.6 s.112
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• pp.457-464
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• 2006

Remarshalling operation is one of the operations considered important in an automated container terminal to perform quickly loading operations and delivery operations. It arranges the containers scattered at a verticla yard block in order to reduce the transfer time and the rehandling time of ATC(Automated Transfer Crane)s. This paper deals with the remarshalling planning problem minimizing the weighted operation time. This problem can be decomposed into 2 subproblems, storage space assignment problem and operation sequencing problem Storage space assignment problem decides to where containers are transported in terms of transportation time cost.. With results of a previous subproblem, operation sequence problem determines the ATC operation sequence, which minimizes the dead-heading of ATC This study formulates each subproblem with mixed integer program and dynamic program. To illustrate the proposed model, we propose an instance to explain the process of remarshalling planning.

• Journal of Power System Engineering
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• v.6 no.1
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• pp.20-26
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• 2002

The purpose of this study is preventing the stick, scuffing, scratch between piston and cylinder in advance, and obtaining data for duration test in actual engine operation. The temperature gradient in cylinder bore according to coolant temperature were measured using $1.5{\ell}$ class diesel engine. 20 thermocouples were installed 2mm deep inside from cylinder wall near top ring of piston in cylinder block, at which points major thermal loads exist. It is suggested as proper measurement points for engine design by industrial engineers. Under full load and $70^{\circ}$, $80^{\circ}C$ and $90^{\circ}C$ coolant temperature conditions, the temperature in cylinder block and engine oil increased gradually according to the increase of coolant temperature, the siamese side temperature of top dead center is $142^{\circ}C$ in peripheral distribution, that is about $20^{\circ}C$ higher than that at thrust, anti-thrust, and rear side temperature, respectively. The maximum pressure of combustion gas in $70^{\circ}C$ coolant temperature is about 2 bar lower than those of $80^{\circ}C$ and $90^{\circ}C$ coolant temperature. The engine torque in $80^{\circ}C$, $90^{\circ}C$ coolant temperature condition is about 4.9Nm higher than that of $70^{\circ}C$ coolant temperature.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.7
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• pp.99-106
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• 2018

The purpose of this study is to examine adaptation types of urban tissue in Ipjeong-dong area, Seoul. Ipjeong-dong area has urban tissue those were made during Joseon dynasty and this is remaining even in the present time. This area was originally urban hanok residential districts till late 1950s. However, it has changed into machinery manufacture business area after demolition of Cheonggyechon shantytown. After several workshops and stores moved in this area, manufacturer and merchants required for more spaces due to lack of room for machinery. To place more workshops in the block, lot alteration were happened and accessibility to workshops inside the block were required. Adaptive road network which is main form of adaptative urban tissue were made to adapt in this kind of poor urban condition. To research about adaptive urban tissue making, distribution were explored and comparison tasks between various cadastral map of 1940, 1964, 1970s and 2017 were conducted. From these tasks, certain types of adaptive urban tissues and characteristics of these elements were found. First of all, forms of adaptive road depend on the surrounded environment. Connecting internal building corridor with original road system is categorized as Type A. Altering a portion of the buildings to make adaptive roads is categorized as Type B. Second, there were two types of formation of adaptive road. Type 1 is for adaptive road which is independent gesture from original road network. Type 2 is for adaptive road which is altering the form of original road network by lengthening or connecting two different dead-end roads.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7863-7867
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• 2014

Background: Retinoblastoma is a rare type of cancer that usually develops in early childhood. If left untreated it can cause blindness and even death. The aim of this study is to determine sociodemographic and clinical features of retinoblastoma patients and also to determine the treatment pattern and outcome in Malaysia. Materials and Methods: Data for this study were retrieved from the Retinoblastoma Registry of the National Eye Database (NED) in Malaysia. Hospital Kuala Lumpur, Hospital Umum Kuching, Sarawak and Hospital Queen Elizabeth, Kota Kinabalu were the major source data providers for this study. Data collected in the registry cover demography, clinical presentation, modes of treatment, outcomes and complications. Results: The study group consisted of 119 patients (162 eyes) diagnosed with retinoblastoma between 2004 and 2012. There were 68 male (57.1%) and 51 (42.9%) female. The median age at presentation was 22 months. A majority of patients were Malays (54.6%), followed by Chinese (18, 5%), Indians (8.4%), and indigenous races (15.9%). Seventy six (63.8%) patients had unilateral involvement whereas 43 patients had bilateral disease (36.1%). It was found that most children presented with leukocoria (110 patients), followed by strabismus (19), and protopsis (12). Among the 76 with unilateral involvement (76 eyes), enucleation was performed for a majority (79%). More than half of these patients had extraocular extension. Of the 40 who received chemotherapy, 95% were given drugs systemically. Furthermore, in 43 patients with bilateral involvement (86 eyes), 35 (41%) eyes were enucleated and 17 (49%) showed extraocular extension. Seventy-two percent of these patients received systemic chemotherapy. The patients were followed up 1 year after diagnosis, whereby 66 were found to be alive and 4 dead. Sixteen patients defaulted treatment and were lost to follow-up, whereas follow-up data were not available in 33 patients. Conclusions: Patients with retinoblastoma in this middle-income Asian setting are presenting at late stages. As a result, a high proportion of patients warrant aggressive management such as enucleation. We also showed that a high number of patients default follow-up. Therefore, reduction in refusal or delay to initial treatment, and follow-up should be emphasized in order to improve the survival rates of retinoblastoma in this part of the world.

• Journal of Chest Surgery
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• v.31 no.6
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• pp.610-614
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• 1998

The first heart-lung transplantation in Korea was successfully performed. The recipient was a 11 year old girl with pulmonary atresia with intact ventricular septum. She had been catheterized at the ages of 4 months, 3 years, 7 years and 10 years, which revealed that neither Fontan nor biventricular repair was feasible. The donor was a traffic accident victim, a 9 year-old boy with the same blood type. The donor was pronounced dead according to the guidelines of the Korean Medical Association's Brain Death Committee. The operation was performed on April 20, 1997. The native heart-lung block was explanted segmentally and donor one was placed above the phrenic nerve using the Arizona technique. After the tracheal anastomosis with single continuous 4-0 prolene, both vena cavae were anastomosed, followed by aortic anastomosis. The graft ischemic time was 145 minutes. The postoperative course was complicated by fever and tracheal stenosis at the anastomosis site. The fever was controlled by anti-tuberculous medications and the tracheal stenosis was relieved by stent(Palmaz 8 mm, 30 mm in length) placement on POD #71. The patient is doing well and is very active in her 7th postoperative month.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.4
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• pp.65-72
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• 1999

This paper tried to find out the various symbolic meanings and functions of landscape elements which Capital City of Shilla Dynasty contains, and what is the symbolism and identity of the city. Basically, this research took the thought of the place and the theory of cognition on landscape as a research tool, and undertook the process of surveying the physical surroundings of the city such as mountains, forests, tumuluses, mountain fortress walls, etc. Especially, the study referenced to a myth, thought, and a tale related to them of the surroundings. The research scope in time had been reached to the year of BC 57 which is beginning year of Shilla Dynasty form AC 467 which is year of introduction of new urban block system delivered from Dang Dynasty of ancient China. The results of research showed symbolic meanings of mountains and forests which is surrounding the Shilla capital from 4 directions of east, west, south and north. Namely, it was the places that the king of the kingdom of Shilla decent into the earth from the heaven. Also, the tumuluses which are located on the center of the capital imitated the surrounding mountains in forms, meaned the place that the dead king rised to heaven. All of these symbolized the Capital City of Dynasty as a sacred city which linked the heaven to earth, and earth to heaven. Finally, this paper suggested the Kyongju which is one of the most representative historic and tourist city in Korea should reflect this kind of symbolic meaning of ancient Capital City of Shilla Dynasty in case of arranging the urban identity plan to promote the quality of urban environment of Kyongju.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.1
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• pp.37-43
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• 2020

This study was conducted to evaluate the effects of different nitrogen levels on the yield and nutrient quality of a newly developed domestic hybrid of Teosinte, Geukdong 6〔Zea mays L. subsp. mexicana (Schrad.) H. H. Iltis〕. The field experiment was conducted in a randomized block design with three replicates and consisted of four nitrogen (N) application rates, T1 (200 kg/ha), T2 (300 kg/ha), T3 (400 kg/ha), and T4 (500 kg/ha). No differences were found in plant length, leaf length, leaf width, leaf number, dead leaves, stem hardness, tiller number, and fresh yield (p>0.05). The T3 showed significantly greater dry matter yield at harvest (heading stage) compared to the other treatments (p<0.05). The crude protein content of T4 (10.49%) was higher than those of T1 and T2 (p<0.05). However, there was no significant difference between T4 (10.49%) and T3 (9.63%). The effects on crude fat, crude ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude fiber were not significant (p>0.05). The sugar content was higher in the T2 treatment than the other treatments (p<0.05). For Ca, T3 showed significantly greater content (p<0.05). However, no significant effects were found in the contents of Cu, Fe, K, Mg, Mn, Mo, and Zn (p>0.05). Na content was higher in order of T2 > T4 > T3 > T1 (p<0.05). Total mineral contents were not significantly different among the treatments (p>0.05). Given these results, we recommend the amount of nitrogen fertilization necessary for "Geukdong 6" to be around 400 kg per ha (T3), when considering, high fresh yield, dry matter yield, number of leaves and content of crude protein.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.3
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• pp.162-168
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• 2022

This study was carried out to investigate the effects of planting densities on the growth characteristics, dry matter yield, and feed value of "Geukdong 6" (a new variety of corn for feed). The experimental design was arranged in a randomized block design with three replications. Treatments consisted of six planting densities, 60 cm × 25 cm (T1), 60 cm × 30 cm (T2), 70 cm × 25 cm (T3), 70 cm × 30 cm (T4), 80 cm × 25 cm (T5) and 80 cm × 30 cm (T6). All treatments were sown on May 14, 2021, and the harvest was on October 3 (late flowering). Plant length and the number of tillers were the highest in T5 (p<0.05), but the number of leaves and stem diameter were the highest in T6 than in the other treatments (p<0.05). Leaf length, leaf width, and dead leaf were not significantly different among the treatments. Organic matter was highest in T6, and crude protein was highest in T5 (p<0.05). The ether extract was not significantly different among the treatments. Crude fiber, NDF, and ADF were highest in T2 with relatively higher planting density (p<0.05). Calcium and phosphorus were not significantly different among the treatments. TDN content was the highest in T3 (p<0.05). Sugar degree (Brix), fructose, glucose, dextran, isomerose, and inverted sugar were not significantly different among the treatment. Fresh yield, dry matter yield and TDN yield were higher in order of T6 > T5 > T4 > T3 > T2 > T1 (p<0.05). Relatively feed value was higher in order of T3 > T6 > T5 > T1 > T4 > T2 (p<0.05). Based on the above results, planting density could be recommended from 80 cm × 30 cm for efficient production of "Geukdong 6".