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Design and Implementation of Clipcast Service via Terrestrial DMB (지상파 DMB를 이용한 클립캐스트 서비스 설계 및 구현)

  • Cho, Suk-Hyun;Seo, Jong-Soo
    • Journal of Broadcast Engineering
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    • v.16 no.1
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    • pp.23-32
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    • 2011
  • Design and Implementation of Clipcast Service via Terrestrial DMB This paper outlines the system design and the implementation process of clipcast service that can send clips of video, mp3, text, images, etc. to terrestrial DMB terminals. To provide clipcast service in terrestrial DMB, a separate data channel needs to be allocated and this requires changes in the existing bandwidth allocation. Clipcast contents can be sent after midnight at around 3 to 4 AM, when terrestrial DMB viewship is low. If the video service bit rate is lowered to 352 Kbps and the TPEG service band is fully used, then 320 Kbps bit rate can be allocated to clipcast. To enable clipcast service, the terminals' DMB program must be executed, and this can be done through SMS and EPG. Clipcast service applies MOT protocol to transmit multimedia objects, and transmits twice in carousel format for stable transmission of files. Therefore, 72Mbyte data can be transmitted in one hour, which corresponds to about 20 minutes of full motion video service at 500Kbps data rate. When running the clip transmitted through terrestrial DMB data channel, information regarding the length of each clip is received through communication with the CMS(Content Management Server), then error-free files are displayed. The clips can be provided to the users as preview contents of the complete VOD contents. In order to use the complete content, the user needs to access the URL allocated for that specific content and download the content by completing a billing process. This paper suggests the design and implementation of terrestrial DMB system to provide clipcast service, which enables file download services as provided in MediaFLO, DVB-H, and the other mobile broadcasting systems. Unlike the other mobile broadcasting systems, the proposed system applies more reliable SMS method to activate the DMB terminals for highly stable clipcast service. This allows hybrid, i.e, both SMS and EPG activations of terminals for clipcast services.

The Correlations between Renminbi Fluctuations and Financial Results of Venture Companies in the Floating Exchange Rate (변동환율제도하의 위안화 환율변동과 벤처기업의 재무성과 간 상관관계 연구)

  • Sun, Zhong-Yuan;Chang, Seog-Ju;Na, Seung-Hwa
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.5 no.1
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    • pp.45-67
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    • 2010
  • On July 21st in 2005, People's Bank of China (PBOC) turned the currency peg against the U.S. dollar into managed currency system based on a basket of unnamed currencies under China's exchanged rate regime. This change means that China's enterprises are not free from currency fluctuations. The purpose of this study is to analyze the relations between Renminbi fluctuations in the floating exchange rate and financial results of venture companies. The process and outcomes of this study are as follows, First, in order to measure the financial results of venture companies, I choose venture companies in Shandong Province listed on the Shanghai Stock Exchange (SSE) at random and several quarter financial sheets according to safety ratios, profitability ratios, growth ratios, activity ratios. Second, I arrange the daily Renminbi exchange rate data announced from July 21st, 2005 to December 31st, 2008 by PBOC into the quarterly data. Third, in order to confirm the relations between Renminbi fluctuations and financial results of venture companies, I carry out Pearson's correlation analysis. As a result, the revaluation of the Chinese Renminbi has weakly negative effects on debt ratio, total assets turnover ratio and equity turnover ratio in statistics. But the revaluation of the Chinese Renminbi is not related to other financial index in statistics. The result of this study is that the revaluation of the Chinese Renminbi has little influence on the export and import of Chinese venture companies and certifies the fact that Chinese venture companies have much foreign currency assets. In addition to avoid the currency exposure risk, this study shows the effective method about currency exposure risk which adjusts proportion of Renminbi to foreign currency.

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A Study on Practices and Improvement Factors of Financial Disclosures in early stages of IFRS Adoption - An Integrative Approach of Korean Cases: Embracing Views of Reporting Entities and Users of Financial Statements (IFRS 공시 실태 개선방안에 대한 소고 - 보고기업, 정보이용자 요인을 고려한 통합적 접근 -)

  • Kim, Hee-Suk
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.7 no.2
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    • pp.113-127
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    • 2012
  • From the end of 1st quarter of 2012, Korean mandatory firms had started releasing financial reports conforming to the K-IFRS(Korean adopted International Financial Reporting Standards). Major characteristics of IFRS, such as 'principles based' features, consolidated reporting, 'fair value' measurement, increased pressure for non-financial disclosures have resulted in brief and various disclosure practices regarding the main body of each statements and vast amount of note description requirements. Meanwhile, a host of previous studies on IFRS disclosures have incorporated regulatory and/or 'compete information' perspectives, mainly focusing on suggesting further enforcement of strengthened requirements and providing guidelines for specific treatments. Thus, as an extension of prior findings and suggestions this study had explored to conduct an integrative approach embracing views of the reporting entities and the users of financial information. In spite of all the state-driven efforts for faithful representation and comparability of corporate financial reports, an overhaul of disclosure practices of fiscal year 2010 and 2011 had revealed numerous cases of insufficiency and discordance in terms of mandatory norms and market expectations. As to the causes of such shortcomings, this study identified several factors from the corporate side and the users of the information; some inherent aspects of IFRS, industry/corporate-specific context, expenditures related to internalizing IFRS system, reduced time frame for presentation. lack of clarity and details to meet the quality of information - understandability, comparability etc. - commonly requested by the user group. In order to improve current disclosure practices, dual approach had been suggested; Firstly, to encourage and facilitate implementation, (1) further segmentation and differentiation of mandates among companies, (2) redefining the scope and depth of note descriptions, (3) diversification and coordination of reporting periods, (4) providing support for equipping disclosure systems and granting incentives for best practices had been discussed. Secondly, as for the hard measures, (5) regularizing active involvement of corporate and user group delegations in the establishment and amendment process of K-IFRS (6) enforcing detailed and standardized disclosure on reporting entities had been recommended.

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The Propagation Behaviour of the Fatigue Crack in the Compact Tension Specimens of the Welded Structural Steels (On according to the difference of the welding direction, the input heat level, the strength of weld material and so on) (용접(鎔接)이음한 구조강(構造鋼)의 소인장시험편(小引張試驗片)에서의 피로구열진전거동(疲勞龜裂進展擧動) (용접방향(鎔接方向), 입열량(入熱量), 용접재료(鎔接材料)의 강도(强度) 등이 다를 때))

  • Chang, Dong Il;Chung, Yeong Wha
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.4 no.2
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    • pp.133-142
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    • 1984
  • With the weld-joined compact tension specimens compared with each other, that is, transverse and lengthwise about the crack propagation direction, high and low in the input heat level, same as and lower than the base metal in the strength of weld material, the fatigue test were performed. With these data, the log-log curves between the fatigue crack propagation rate ${\frac{da}{dN}}$ and the transition range of the stress intensity factor ${\Delta}K$ ahead the crack tip were drawed. These curves were compared and estimated among each compared specimens, among each zones, that is, the base metal, the heat-affected metal and the weld-mixed metal, and between this study and the past studies. Basically, Little difference in the slope of the $da/dN-{\Delta}K$ relation was showed in all the welded directions, all the input heat levels and all the zones. But, First, to comparison with in the past studies about the base metals, it was showed that da/dN started in the much later rate, increased faster and stoped in the little faster rate. Second, it was showed that, near the time the crack's going from the heat-affected zone to the weld-mixed metal da/dN decreased a little for a while. Third, in the lengthwise weld compared with the transverse weld, in the high input heat weld compared with the low input heat weld in the case used the weld material of the same strength as the base metal, in the opposite case in the case used the one of the lower strength than the base metal, in the case used the weld material of the same strength as compared with the lower strength than the base metal beside the high input heat and the lengthwise weld, it was showed that the crack occured earlier in lower ${\Delta}K$ and later da/dN, the curves went with the same slope. Forth, in the lengthwise weld compared with the transverse weld in the low input heat weld, in the low input heat weld compared with the high input heat weld, it was showed that da/dN went with the lower level.

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Determination of Electron Spin Relaxation Time of the Gadolinium-Chealted MRI Contrast Agents by Using an X-band EPR Technique (EPR을 통한 상자성 자기공명 조영제의 전자스핀 이완시간의 결정)

  • Sung-wook Hong;Yongmin Chang;Moon-jung Hwang;Il-su Rhee;Duk-Sik Kang
    • Investigative Magnetic Resonance Imaging
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    • v.4 no.1
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    • pp.27-33
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    • 2000
  • Purpose: To determine the electronic spin relaxation times, $T_{le}$, of three commercially available Gd-chelated MR contrast agents, Gd-DTPA, Gd-DTPA-BMA and Gd-DOTA, using Electron Paramagnetic Resonance(EPR) technique. Material and Methods: The paramagnetic MR contrast agents, Gd-DTFA(Magnevist) , Gd-DTFA-BMA(OMNISCAN) and Gd-DOTA(Dotarem), were used for this study, The EPR spectra of these contrast agents, which were prepared 2:1 methanol/water solution, were obtained at low temperatures, from $-160^{\circ}C~20^{\circ}C$. The glassy-state EPR spectra for these contrast agents were then fitted by the simulation spectra generated with different zero-field splitting (ZFS) parameters by a computer simulation program 'GEN', which generates the EPR powder spectrum using a given ZFS in $3{\times}3$ tensor. Finally, the spin relaxation times of the contrast agents were then determined from the $T_{2e}$, D, and E values of the best simulation spectra using the McLachlan's theory of average relaxation rate. Results: The electronic transverse spin relaxation times, $T_{2e}'s$, of Gd-DTPA, Gd-DTPA-BMA and Gd-DOTA were 0.113ns, 0.147ns and 1.81ns respectively. The g-values were 1.9737, 1.9735 and 1.9830 and the electronic spin relaxation times, $T_{1e}'s$, were 18.70ns, 33.40ns and $1.66{\mu}s$, respectively. Conclusion: The results of these studies reconfirm that the paramagnetic MR contrast agents with larger ZFS parameters should have shorter $T_{1e}'s$. Among three contrast agents used for this study, Gd-DOTA chelated with cyclic ligand structure shows better electronic property then the others with linear structure. Thus, it is concluded that the exact determination of ZFS parameters is the important factor in evaluating relaxation enhancement effect of the agents and in developing new contrast agents.

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Frequency and clinical characteristics of prenatally diagnosed congenital hydronephrosis and outcomes of ureteropelvic junction stenosis (산전 진단된 선천성 수신증의 빈도 및 임상적 특성과 신우요관 이행부 협착의 경과)

  • Kang, Hyun Soo;Sung, June Seung;Kim, Sun Hui;Back, Hee Jo;Kim, Young Ok;Kim, Chan Jong;Choi, Young Youn;Hwang, Tai Ju
    • Clinical and Experimental Pediatrics
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    • v.49 no.8
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    • pp.870-874
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    • 2006
  • Purpose : Popular use of fetal ultrasonography has increased to detect congenital hydronephrosis(CH) which is the most common anomaly prenatally detected. We'd like to determine the frequency and clinical characteristics of prenatally diagnosed CH and outcome of ureteropelvic junction stenosis(UPJS). Methods : The records of births between January 1994 and June 2003 in Chonnam National University Hospital(CNUH), and the records of children who were diagnosed with CH in the Department of Pediatrics of CNUH during the above period, were retrospectively analyzed. In the patients with UPJS, the initial anterior posterior diameters of renal pelvis(APD) were compared between the spontaneous regression (SR) and operation group(OP). In the SR group, sequential regression rates of APD were estimated. Results : Among a total 9,076 births, 231(2.54 percent) patients with 293 renal units were diagnosed as CH and 19(6.78 percent) renal units spontaneously regressed 3 days after birth. In 228 children(56 bilateral; 172 unilateral; total 284 renal units) diagnosed with CH in the department of pediatrics of CNUH, male(71.9 percent) and left kidney(69.2 percent) predilection were found and 78.1 percent of CH were caused by UPJS. The initial APD of the SR group(121 units) in UPJS was $7.8{\pm}6.28mm$, which was significantly smaller than the APD($26.8{\pm}12.14mm$) of the OP group(25 unit)(P<0.05). In the SR group, 81 percent spontaneously regressed within one year. Conclusions : In CH, male and left kidney predilection were found. UPJS was the most common cause of CH and initial APD in UPJS at 3 days of age was a good prognostic indicator. Close monitoring should be done for at least one year because most SR in UPJS regressed spontaneously within one year.

A Clinical Study of Acute Colonic Diverticulitis in Children (소아에서 발생한 급성 대장 게실염의 임상적 고찰)

  • Sim, Jae Hoon;Song, Keum Ho;Sim, Yun Jung;Cho, Do Jun;Kim, Dug Ha;Min, Ki Sik;Yoo, Ki Yang;Lee, Hae Ran;Lee, Kwan Seop
    • Clinical and Experimental Pediatrics
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    • v.46 no.11
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    • pp.1095-1100
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    • 2003
  • Purpose : Children with acute colonic diverticulitis(ACD), can be misdiagnosed with acute appendicitis. Methods : We reviewed 15 cases of ACD during five years, from January 1998 to June 2002 retrospectively. Results : Most patients(80%) with ACD in children presented with right lower quadrant pain. The primary diagnosis on admission was mostly acute appendicitis(87%), and all ACD in children occurred in the right colon. Fourteen patients were managed by conservative treatment including antibiotics. A follow-up study was performed in 15 patients. There were symptomatic recurrences in two patients, but no significant complication was noted. The frequency of ACD was 11.7 per 1000 acute appendicitis. Conclusion : ACD in children can mostly be cured by conservative treatment. It is prudent to choose the management through the diagnostic work up, including abdominal sonography and computed tomography, because there was no significant difference of clinical findings between ACD and acute appendicitis.

Changes in platelet counts caused by valproate in children with epilepsy (소아 간질 환자에서 valproate 투여 후 혈소판 수의 변화)

  • We, Ju Hee;Kim, Young Mi;Nam, Sang Ook
    • Clinical and Experimental Pediatrics
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    • v.52 no.1
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    • pp.75-80
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    • 2009
  • Purpose : In adults, valproate (VPA) has been reported to be associated with thrombocytopenia. However, few studies have investigated this association in children, and the factors affecting platelet counts remain controversial. This study was undertaken to investigate changes in platelet counts following VPA therapy and related factors in children with epilepsy. Methods : Our subjects comprised 75 epileptic children who had received VPA monotherapy for at least 1 year between January 2000 and December 2005. We regularly examined platelet counts at intervals of 6 to 12 months after baseline platelet counts before VPA treatment. We analyzed changes in platelet counts according to several factors such as sex, seizure type, underlying causes of epilepsy, age at the start of medication as well as at the last follow up, duration of VPA administration, VPA dose, serum VPA level, and body weight at the last follow up. Results : Overall, the platelet counts decreased significantly after VPA therapy. The average baseline platelet count was $312.5{\pm}109.1{\times}10^6/mL$. At the last follow up, the average platelet count was $261.7{\pm}72.2{\times}10^6/mL$. We observed the relationship between platelet counts and serum levels of VPA; while children with serum VPA <$75{\mu}g/mL$ showed no change in platelet counts (P=0.102), children with serum VPA >$75{\mu}g/mL$ showed a significant decrease in platelet counts. Conclusion : VPA may cause a significantly decreased platelet count in children with epilepsy. High serum VPA levels were associated with development of thrombocytopenia.

Prevalence and trends in obesity among Korean children and adolescents in 1997 and 2005 (한국 소아청소년의 비만 유병률 추이: 1997년과 2005년 비교)

  • Oh, Kyungwon;Jang, Myoung Jin;Lee, Na Yeoun;Moon, Jin Soo;Lee, Chong Guk;Yoo, Myung Hwan;Kim, Young Taek
    • Clinical and Experimental Pediatrics
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    • v.51 no.9
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    • pp.950-955
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    • 2008
  • Purpose : The objective of this study was to provide current estimates of the prevalence and examine trends of overweight and obesity in children and adolescents. Methods : Height and weight measurements from 183,159 (112,974 in 1997, 70,185 in 2005) children and adolescents aged 2 to 18 years were obtained via the 1997 and 2005 National Growth Survey. Obesity among children and adolescents was defined as being at or above the 95th percentile of the gender-specific body mass index (BMI) for age in the 2007 Korean National Growth Charts or a BMI of 25 or higher; overweight was defined as being at or above the 85th percentile to less than the 95th percentile BMI. Results : In 2005, 9.7% (11.3% for boys, 8.0% for girls) of South Korean children and adolescents were obese; 19.0% (19.7% for boys, 18.2% for girls) were overweight or obese. The overall prevalence of obesity increased from 5.8% in 1997 to 9.7% in 2005 (from 6.1% in 1997 to 11.3% in 2005 for boys and from 5.5% in 1997 to 8.0% in 2005 for girls); the increasing trend was most evident in boys, especially those aged 13-18 years. Conclusion : The prevalence of obesity among children and adolescents increased significantly during the eight-year period from 1997 to 2005. This study suggests that we need to make a priority of developing strategies to control obesity in children and adolescents; the potential health effects of increases in obesity are of considerable public health importance.

Influence of Short-term Application of Abscisic Acid in Nutrient Solution on Growth and Drought Tolerance of Tomato Seedlings (토마토 육묘과정에서 단기간 ABA처리가 묘소질과 건조내성에 미치는 영향)

  • Kim, Il-Seop;Vu, Ngoc-Thang;Vo, Hoang-Tung;Choi, Ki-Young;Kim, Young Shik
    • Journal of Bio-Environment Control
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    • v.24 no.1
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    • pp.13-20
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    • 2015
  • This study was conducted to evaluate influence of short-term application of abscisic acid (ABA) in nutrient solution on growth and drought tolerance of tomato seedlings. The treatments included four ABA concentrations (0.5, 1, 2, $3mg{\cdot}L^{-1}$) and control (non-treatment) were applied to the nutrient solution in a hydroponic system. On the $5^{th}$ and $10^{th}$ day after growing in the nutrient solution containing ABA, seedlings were transferred to -5 bars of PEG-8000 in a growth chamber to induce water stress. Except for stem diameter and fresh and dry weight of root, there were no statistical differences in other growth parameters among control, 0.5 and $1mg{\cdot}L^{-1}$ of ABA treatments. Seedlings growths were strongly inhibited in nutrient solution containing 2 and $3mg{\cdot}L^{-1}$ of ABA. The root growth such as fresh and dry weigh of root, total root surface area, and average root diameter was slightly enhanced in $1mg{\cdot}L^{-1}$ of ABA treatment. The elevation of ABA concentrations in nutrient solution resulted in the decrease in transpiration rate and increase in stomatal diffusive resistance and leaf temperature of tomato seedlings. The initiations of seedling wilting after treating in -5 bars of PEG were delayed from 10 hrs in control to 30 hrs in ABA applied treatments. Additionally, the high percentages of recovered seedlings were observed in 0.5 and $1mg{\cdot}L^{-1}$ of ABA treatments after re-irrigation. Therefore, short-term application of $1mg{\cdot}L^{-1}$ of ABA in the nutrient solution stimulated the root growth and drought tolerance of tomato seedlings by delaying the start time of wilting point and enhancing the recovery after re-irrigation.