• Title/Summary/Keyword: Vertical Transmission

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Establishment Method of the Regulatory Framework for Communications Reflecting the Ecosystem Elements (생태계 요소를 반영한 방송통신 규제체계의 정립 방안)

  • Hong, Dae-Sik;Choe, Dong-Uk
    • Journal of Legislation Research
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    • no.41
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    • pp.401-434
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    • 2011
  • The discussion on the adoption of the horizontal regulatory framework is underway to overcome the problems regarding the vertical regulatory framework resulting from a convergence of broadcasting and telecommunications services. Recently, however, the horizontal regulatory framework shows its limitation to regulate the ecosystem established mainly by Google and Apple. The existing horizontal regulatory framework does not fully reflect the characteristics of the two-sided market and the change in the competition structure in the broadcasting and telecommunications sector. What is important to note is that if the existing horizontal regulatory framework is simply applied to the ecosystem, a regulatory imbalance can be caused among ecosystems. The existing horizontal regulatory framework, which is subject to a value chain structure, categorizes business entities into either contents layer or transmission layer and applies the same regulation to all business entities in the same category. However, in the ecosystem, a keystone-player can be categorized into different layers depending on its strategy. Therefore, if the existing horizontal regulatory framework is applied as it is, the regulatory imbalance between keystone-players located in less regulated areas and keystone-players located in more regulated areas occurs resulting in a distortion of competition. There are two possible ways to establish a new regulatory framework to prevent the distortion of competition likely to be caused by the adoption of a horizontal regulatory system. First, a new ecosystem regulatory framework different from the existing one can be established. Second, the horizontal regulatory framework can be modified to reflect the ecosystem elements. The first approach is hard to adopt given the current situation as the approach requires the analysis of all broadcasting and telecommunications ecosystems including mobile and wired services; currently research and study on the competition conditions in the ecosystems is not enough. Therefore, this paper supports the second approach proposing a modified horizontal regulatory framework through the improvement of institutions and remedies suitable for accommodating the ecosystem elements. This paper intends to propose a way to regulate broadcasting and telecommunications ecosystems taking into consideration the ecosystem elements on top of the Telecommunications Business Act, Broadcasting Act, IPTV Act, the competition condition evaluation system of the Basic Act on Broadcasting and Telecommunications Development, and regulation on common carriers under the Telecommunications Business Act.

Development of a split beam transducer for measuring fish size distribution (어체 크기의 자동 식별을 위한 split beam 음향 변환기의 재발)

  • 이대재;신형일
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.37 no.3
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    • pp.196-213
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    • 2001
  • A split beam ultrasonic transducer operating at a frequency of 70 kHz to use in the fish sizing echo sounder was developed and the acoustic radiation characteristics were experimentally analyzed. The amplitude shading method utilizing the properties of the Chebyshev polynomials was used to obtain side lobe levels below -20 dB and to optimize the relationship between main beam width and side lobe level of the transducer, and the amplitude shading coefficient to each of the elements was achieved by changing the amplitude contribution of elements with 4 weighting transformers embodied in the planar array transducer assembly. The planar array split beam transducer assembly was composed of 36 piezoelectric ceramics (NEPEC N-21, Tokin) of rod type of 10 mm in diameter and 18.7 mm in length of 70 kHz arranged in the rectangular configuration, and the 4 electrical inputs were supplied to the beamformer. A series of impedance measurements were conducted to check the uniformity of the individual quadrants, and also in the configurations of reception and transmission, resonant frequency, and the transmitting and receiving characteristics were measured in the water tank and analyzed, respectively. The results obtained are summarized as follows : 1. Average resonant and antiresonant frequencies of electrical impedance for four quadrants of the split beam transducer in water were 69.8 kHz and 83.0 kHz, respectively. Average electrical impedance for each individual transducer quadrant was 49.2$\Omega$ at resonant frequency and 704.7$\Omega$ at antiresonant frequency. 2. The resonance peak in the transmitting voltage response (TVR) for four quadrants of the split beam transducer was observed all at 70.0 kHz and the value of TVR was all about 165.5 dB re 1 $\mu$Pa/V at 1 m at 70.0 kHz with bandwidth of 10.0 kHz between -3 dB down points. The resonance peak in the receiving sensitivity (SRT) for four combined quadrants (quad LU+LL, quad RU+RL, quad LU+RU, quad LL+RL) of the split beam transducer was observed all at 75.0 kHz and the value of SRT was all about -177.7 dB re 1 V/$\mu$Pa at 75.0 kHz with bandwidth of 10.0 kHz between -3 dB down points. The sum beam transmitting voltage response and receiving senstivity was 175.0 dB re 1$\mu$Pa/V at 1 m at 75.0 kHz with bandwidth of 10.0 kHz, respectively. 3. The sum beam of split beam transducer was approximately circular with a half beam angle of $9.0^\circ$ at -3 dB points all in both axis of the horizontal plane and the vertical plane. The first measured side lobe levels for the sum beam of split beam transducer were -19.7 dB at $22^\circ$ and -19.4 dB at $-26^\circ$ in the horizontal plane, respectively and -20.1 dB at $22^\circ$ and -22.0 dB at $-26^\circ$ in the vertical plane, respectively. 4. The developed split beam transducer was tested to estimate the angular position of the target in the beam through split beam phase measurements, and the beam pattern loss for target strength corrections was measured and analyzed.

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Prevalence Report of Transovarian Transmitted Diseases in the Breeder Chickens, Korea (국내 종계에서 난계대 전염병 감염 실태 보고)

  • Kwon, Yong-Kuk;Kang, Min-Soo;Oh, Jae-Young;Jung, Byeong-Yeal;Kim, Hye-Ryoung;Kim, Ha-Young;Shin, So-Yeon;Kwon, Jun-Hun;Chung, Gab-Soo
    • Korean Journal of Poultry Science
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    • v.37 no.3
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    • pp.237-245
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    • 2010
  • A survey of transovarially transmitted diseases, including salmonellosis [(pullorum disease; PD)/(fowl typhoid; FT)], mycoplasmosis, avian infectious anemia (CIA), and fowl adenovirus infection was conducted in the breeder chickens from August to December in 2009. The numbers of flocks sampled out were: Grand Parents Stock (GPS), 45; Parents Stock (PS) 1,018, Baeksemi breeder (BSB) 54. The seroprevalence of salmonellosis (PD/FT) were 0% (GPS), 3.2% (PS), and 3% (BSB), respectively. A total of 983 chicken farms were affected with FT outbreaks between 2000 and 2008. The incidence of FT in commercial broilers, Baeksemi, commercial layers, native chickens, and broiler breeders was 44.3%, 26.2%, 15.7%, 12.6% and 1.08%, respectively. Of the affected broilers, over 90% birds were under 2 weeks of age, indicating it was possible that they were infected with S. gallinarum via vertical transmission. The sero-positive flocks against Mycoplasma gallisepticum (MG) were 71.1% (GPS), 88.7% (PS), 88.7% (BSB), while the rates of positive flocks against Mycoplasma synoviae (MS) were 86.0% (GPS), 77.0% (PS), and 98.0% (BSB). In GP and parent farms, the detection rates on specific genes of CIA virus were 19/45 (42.2%), and 169/1039 (18.0%), respectively, whereas the seroprevalence of CIA were 86.0% in GPS and 93.7% in PS flocks. In addition, positive flocks of fowl adenoviruses were 4.4% (GPS), 2.7% (PS) and 9.35% (BSB), respectively. As the results, avian mycoplasmosis and CIA have been more prevailing in chicken breeder than avian salmonellosis and fowl adenovirus infection in Korea.

The Immune Response and Protective Efficacy of Hepatitis B Vaccine in Neonates Born from Hepatitis B Carrier Mothers (B형 간염 바이러스 보유 산모로부터 분만된 신생아의 B형 간염 백신의 면역반응 및 방어효과)

  • Kim, Jong-Hyun;Kang, Jin-Han;Hur, Jae-Kyun;Koh, Dae-Kyun;Oh, Chang-Kyu
    • Pediatric Infection and Vaccine
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    • v.5 no.1
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    • pp.96-103
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    • 1998
  • Purpose : We performed this study to evaluate the immune responses and protective efficacies of the HBV vaccine in infants born from hepatitis B virus(HBV) carrier mothers. Methods : Seventy eight infants born from HBV carrier mothers, who were able to follow up for 12months in the Catholic University St. Vincents hospital, were involved in this study from July 1995 to December 1996. Samples were collected at birth, 4, 8 and 12months after injection of HBIG and HBV heat-inactivated plasma derived vaccines. We evaluated the changes and relationships of viral markers detecting by enzyme immunoassay and radioimmunoassay between HBV carrier mothers and their infants. Results : 1) A total of 5.0%(106/2,117) of pregnant women were found to be a HBV carrier. The rates of HBeAg positive and negative were 38.5%(37/96) and 61.5%(59/96), respectively. 2) The seroconversion rates of anti-HBs with infants of HBV carrier mothers at 4, 8 and 12 months were 85.9%(67/78), 75.6%(59/78) and 73.1%(57/78), respectively. Although these were statistically significant differences(P<0.05), they were not related to HBeAg status of the mothers. The geometric mean titers of anti-HBs at 8 and 12 months were significantly higher than at 4 months, statistically(P<0.05). The protective efficacy of the HBV vaccine and HBIG at 12 months in infants from HBeAg positive and negative mothers were 89.8% and 100%, respectively. 3) Five of 78(6.4%) infants became infected by HBV from only HBeAg positive mothers during the follow up period of 12 months. Three of 5 infected infants became HBV carriers. HBsAg positive at birth from HBeAg positive and negative mother were 4 infants, respectively. Three of 4 infants became infected by HBV from only HBeAg positive mothers. Conclusion : We confirmed that the seroconversion rate of HBV heat-inactivated plasma derived vaccine which was one of other vaccines manufacturing in Korea was 85.9%. The protective efficacy of this HBV vaccine and HBIG at 12 months in infants from HBeAg positive and negative mothers were 89.8% and 100%, respectively.

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The Site Effect of the Broadband Seismic Stations in Korea (국내 광대역 지진 관측소의 부지효과)

  • Wee, Soung-Hoon;Kim, Sung-Kyun
    • Economic and Environmental Geology
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    • v.41 no.2
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    • pp.225-242
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    • 2008
  • The site effect for 23 broadband seismic stations in the southern Korean Peninsula was estimated by using the spectral ratio of coda waves. In principle, the site effect means the pure amplification below the station excluding effects of seismic source and attenuation in the wave transmission. However, the site effect determined in this study is equivalent with the relative site amplification factor to the mean amplification for all stations. A total of 500 three-component seismograms from 35 earthquakes, of which magnitude ranged from 2.5 to 5.1 occurred from January, 2001 to January, 2007 was used to obtain the site amplification factor. The site amplification factors were estimated for the frequency bands centered at 0.2, 0.5, 1, 2, 5, 10, 15, and 20 Hz. It was found that the factors for two horizontal components of transverse and radial records were concordant with each other in the all frequency bands. However, the factor for the vertical component was found to be systematically lower than those for two horizontal components. The factors obtained in the low frequency band below 2 Hz ranged from 0.5 to 1.5 in all seismic stations except for KMA and KIGAM stations in Bagryeongdo (BRD1 and BRD2) of which factor showed high value above 1.5. Some stations such as SEO, SNU, HKU, NPR, and GKPI showed high value above 1.5 in the high frequency band from 5 to 20 Hz. Especially, the factors of GKP1 station represented extremely high value ranging from 1.8 to 7.8. Also, the factors for stations of KWJ, SND, and ULJ showed low value below 0.5. The spatial distribution for the relative amplification factor represented a tendency of being approximately lower in north-eastern area than south-western area in the southern Korean Peninsula.

Reproduction of the Dyeing Technique Used for the Small Flower Pattern Clamp Resist Dyed Fine Tabby in Amitabha of 1302 (1302년 아미타불복장 소화문협힐견(小花紋��纈絹) 염색기법 재현)

  • Choi, jungim;Sim, Yeon-ok
    • Korean Journal of Heritage: History & Science
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    • v.52 no.2
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    • pp.254-267
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    • 2019
  • Clamp resist dyeing is a resist dyeing technique in which a fabric is sandwiched between two or more pieces of woodcarving and then a pattern is expressed by dyeing. Records from nine years of King Heungdeok's reign during the Unified Silla dynasty show that the use of the clamp resist dyeing technique was banned for different garments. This was only for garments of YOOKDUPUMNYEO (六頭品女) or OHDUPUMNYEO (五頭品女). Given this, it can be assumed that clamp resisted fabrics were widely used, and the technique had been established during the Unified Silla dynasty or before. However, only the term can be found in the records. Neither its definition nor how this technique was used is explained. Also, it is difficult to assume the types and features of clamp resist dyeing due to a lack of materials. A small number of relics from the Goryeo dynasty still remain, though. Craft techniques have developed through international exchanges and have changed according to respective nations' circumstances including politics, economics, society, and culture. Hence, this research analyzed documents and relics from China and Japan, two countries neighboring the Republic of Korea, and studied the different types and features of clamp resist dyeing techniques. Clamp resist dyeing techniques were divided into monochromatic or multichromatic according to the number of colors that represented patterns, rather than according to the respective nations' features. They were also classified into mono, bilateral symmetry, or vertical-bilateral symmetry according to the structure of the patterns. Through the study of examples of inherited or reproduced dyeing techniques in China and Japan, it was confirmed that different engraving techniques, including relief, openwork, intaglio fit for the feature of a pattern and the number of colors, were applied in order to vividly represent patterns on fabric. Using small flower pattern clamp resist dyed fine tabby in Amitabha of 1302, the only relic showing its patterns and colors in Korea, as the experiment subject, this research successfully reproduced a clamp resist dyeing technique through a successful experiment based on the basic materials from the dyeing technique case study. Due to the significance of the experiment on a clamp resist dyeing technique that stopped its transmission and shows the features of the technique, this study is expected to be a basic resource that can be used for future reproductions of multichromatic clamp resist dyeing techniques. Also, it is expected to be helpful in widening and recreating the world of Korean pattern dyeing with modern dyeing techniques.

Chronic HBV Infection in Children: The histopathologic classification and its correlation with clinical findings (소아의 만성 B형 간염: 새로운 병리조직학적 분류와 임상 소견의 상관 분석)

  • Lee, Seon-Young;Ko, Jae-Sung;Kim, Chong-Jai;Jang, Ja-June;Seo, Jeong-Kee
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.1 no.1
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    • pp.56-78
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    • 1998
  • Objective: Chronic hepatitis B infection (CHB) occurs in 6% to 10% of population in Korea. In ethinic communities where prevalence of chronic infection is high such as Korea, transmission of hepatitis B infection is either vertical (ie, by perinatal infection) or by close family contact (usually from mothers or siblings) during the first 5 years of life. The development of chronic hepatitis B infection is increasingly more common the earlier a person is exposed to the virus, particularly in fetal and neonatal life. And it progress to cirrhosis and hepatocellular carcinoma, especially in severe liver damage and perinatal infection. Histopathology of CHB is important when evaluating the final outcomes. A numerical scoring system which is a semiquantitatively assessed objective reproducible classification of chronic viral hepatitis, is a valuable tool for statistical analysis when predicting the outcome and evaluating antiviral and other therapies. In this study, a numerical scoring system (Ludwig system) was applied and compared with the conventional histological classification of De Groute. And the comparative analysis of cinical findings, family history, serology, and liver function test by histopathological findings in chronic hepatitis B of children was done. Methods: Ninety nine patients [mean age=9 years (range=17 months to 16 years)] with clinical, biochemical, serological and histological patterns of chronic HBV infection included in this study. Five of these children had hepatocelluar carcinoma. They were 83 male and 16 female children. They all underwent liver biopsies and histologic evaluation was performed by one pathologist. The biopsy specimens were classified, according to the standard criteria of De Groute as follows: normal, chronic lobular hepatitis (CLH), chronic persistent hepatitis (CPH), mild to severe chronic active hepatitis (CAH), or active cirrhosis, inactive cirrhosis, hepatocellular carcinoma (HCC). And the biopsy specimens were also assessed and scored semiquantitatively by the numerical scoring Ludwig system. Serum HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc (IgG, IgM), and HDV were measured by radioimunoassays. Results: Male predominated in a proportion of 5.2:1 for all patients. Of 99 patients, 2 cases had normal, 2 cases had CLH, 22 cases had CPH, 40 cases had mild CAH, 19 cases had moderate CAH, 1 case had severe CAH, 7 cases had active cirrhosis, 1 case had inactive cirrhosis, and 5 cases had HCC. The mean age, sex distribution, symptoms, signs, and family history did not differ statistically among the different histologic groups. The numerical scoring system was correlated well with the conventional histological classification. The histological activity evaluated by both the conventional classification and the scoring system was more severe as the levels of serum aminotransferases were higher. In contrast, the levels of serum aminotransferases were not useful for predicting the degree of histologic activity because of its wide range overlapping. When the histological activity was more severe and especially the cirrhosis more progressing, the prothrombin time was more prolonged. The histological severity was inversely related with the duration of seroconversion of HBeAg. Conclusions: The histological activity could not be accurately predicted by clinical and biochemical findings, but by the proper histological classification of the numerical scoring system for the biopsy specimen. The numerical scoring system was correlated well with the conventional histological classification, and it seems to be a valuable tool for the statistical analysis when predicting the outcome and evaluating effects of antiviral and other therapies in chronic hepatitis B in children.

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