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Phylogentic Position, Pigment Content and Optimal Growth Condition of the Unicellular Hydrogen-Producing Cyanobacterial Strains from Korean Coasts (한국 연안산 단세포성 수소생산 남세균 종주들의 분류계통, 색소함량 및 최적성장 환경)

  • PARK, JONG-WOO;KIM, JU HEE;CHO, AE-RA;JUNG, YUN-DUK;KIM, PYOUNG JOONG;KIM, HYUNG-SEOP;YIH, WONHO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.20 no.3
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    • pp.131-140
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    • 2015
  • To set up unicellular cyanobacterial strains with photo-biological $H_2$ production potential, live samples were repeatedly collected from 68 stations in the coastal zone of Korea for the four years since 2005. Among 77 cyanobacterial strains established six (KNU strains, CB-MAL002, 026, 031, 054, 055 and 058) were finally chosen as the excellent strains for $H_2$ production with $H_2$ accumulation over 0.15 mL $H_2\;mL^{-1}$ under general basic $H_2$ production conditions as well as positive $H_2$ production for more than 60 hr. To explore optimum procedures for higher $H_2$ production efficiency of the six cyanobacterial strains, the inter-strain differences in the growth rate under the gradients of water temperature and salinity were investigated. The maximum daily growth rates of the six strains ranged from 1.78 to 2.08, and all of them exhibited $N_2-fixation$ ability. Based on the similarity of the 16S rRNA sequences, all the test strains were quite close to Cyanothece sp. ATCC51142 (99%). The six strains, however, were grouped into separate clades from strain ATCC51142 in the molecular phylogeny diagram. Chlorophyll- a content was 3.4~7.8% of the total dried weight, and the phycoerythrin and phycocyanin contents were half of those in the Atlantic strain, Synechococcus sp. Miami BG03511. The growth of the six strains was significantly suppressed at temperatures above the optimal range, $30{\sim}35^{\circ}C$, to be nearly stopped at $40^{\circ}C$. The growth was not inhibited by high salinities of 30 psu salinity in all the strains while strain CB055 maintained its high growth rate at low salinities down to 15 psu. The euryhaline strains like CB055 might support massive biotechnological cultivation systems using natural basal seawater in temperate latitudes. base seawater. The biological and ecophysiological characteristics of the test strains may contribute to designing the optimal procedures for photo-biological $H_2$ production by unicellular cyanobacteria.

Stress Indices of Hollow Circular Cross Section Welded Attachments on Piping Elbows with the Extended Parameters Range (매개변수 적용범위를 확장한 배관 곡관부에 용접 부착된 원형관 이음부의 이차응력지수)

  • Lee, Kun-Suk;Moon, Seong-Jae
    • Plant Journal
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    • v.15 no.4
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    • pp.43-51
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    • 2019
  • The stress concentration of the integral welded attachments (IWA) often used to support piping system has been a big issue because it induces local stresses in piping. The method to evaluate local stresses associated with attachments on elbows has been suggested in EPRI TR-107453. However, there are limitations regarding specific parameters range in order to use correlation equation. In this paper, parametric study based on piping elbow size and attachment dimension was performed utilizing finite element analysis (FEA) to evaluate the secondary stress indices of hollow circular cross section welded attachments on piping elbows with the extended parameters range. The results of the FEA were used to develop correlation formulas for calculating secondary stress indices. The empirical equations in this study are suggested as an alternative evaluation method of EPRI TR-107453 by extending parameters range.

Judgement of Violation of the Protection Duty of Internet Service Provider (인터넷 서비스 제공자의 보호조치 의무 위반의 판단)

  • Kang, Juyoung;Kim, Hyunji;Lee, Hwansoo
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.6 no.7
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    • pp.17-26
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    • 2016
  • Information spill was occurred several times in the country due to the negligence of the large internet service providers including SK Communications, Auction, KT. In order to judge the Internet Service Provider(ISP)'s liability in individual data spill caused by hacking, the violation of existing legislation or general principle of law's good faith principle has to be examined. However, based on current ISP's good faith principle, there is no objective standard for judging liability. Such uncertain range of protection action duty based on good faith principle generates complaint toward companies, therefore presentation of objective judgement range index on how to determine this range is needed. However due to the legal characteristic of above-mentioned law, it is not possible to fix the range of protection action duty and regulate it on law. In order to resolve this, rather than concerning simply on legal system level, fusion approach method is needed. Thus, this research will discuss the measure for objective standard for predicting ISP's range of protection action duty through fusion view dividing in technical, legal and administrative aspects.

A study on the optimum range of reinforcement in tunneling adjacent to structures (구조물 근접 터널시공시 최적의 보강범위에 관한 연구)

  • Lee, Hong-Sung;Kim, Dae-Young;Chun, Byung-Sik;Jung, Hyuk-Sang
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.11 no.2
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    • pp.199-211
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    • 2009
  • Development of underground space is actively performed globally for better life in the surface, and the scale of the space is increasing. Extreme care should be taken in the construction of the underground space in urban areas in order to avoid damage of adjacent structures and interference with existing underground space. In case of shallow tunnels, reinforcement of ground and structures is necessary to minimize the damage to structures due to excavation but any standard for optimum range of the reinforcement has not been established yet. In this paper, a series of numerical analyses have been performed for a 20 m diameter tunnel excavated underneath a structure to investigate the degree of damage of the structure according to vertical and horizontal spacing between the tunnel and structure. In addition to that, optimum range of reinforcement is presented for each case where reinforcement is required. It has been observed that the reinforcement is necessary for the ground condition adapted in the analyses as follows: (1) if horizontal spacing ($S_{H}$) approaches to 0D (D: equivalent diameter of tunnel) for vertical spacing (Sv) of 0.5D, and (2) if tunnel exists underneath the structure for vertical spacing (Sv) of 0.75D. The reinforcement is not necessary for Sv of 10 regardless of $S_{H}$. It also has been obtained that the optimum ranges of the reinforcement around structure foundation are 7 m in depth and whole width of the structure and 5 m beyond tunnel sidewall. These reinforcememt ranges have been confirmed to be enough for stability of the structure if types of reinforcement method is appropriately selected.

Pneumococcal Surface Protein A of Streptococcus pneumoniae Isolates from Koreans (한국인에서 Streptococcus pneumoniae 분리주의 폐구균 표면 단백 A)

  • Kim, Kyung Hyo
    • Clinical and Experimental Pediatrics
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    • v.48 no.11
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    • pp.1206-1211
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    • 2005
  • Purpose : Pneumococcal protein vaccine based on pneumococcal surface protein A (PspA) is in development with the potential to offer a broad range of protection against different strains. PspA elicits protection in mice against fatal sepsis as well as carriage and lung infection. This study was performed to investigate the frequency of PspA families among Streptococcus pneumoniae recovered from Korean children and adults. Methods : A total of 89 pneumococcal isolates was included in the study. They were capsule serotyped by the slide agglutination assay with commercial antisera. PspA families were determined with polymerase chain reaction using the pair of primers for family 1 and family 2. Results : Seventeen pneumococcal serotypes were found in a total of 89 isolates. PspA typing was able to ascertain 79 of the 89 isolates (88.8 percent). Among these, 20 (22.5 percent) isolates were family 1 PspA, 59 (66.3 percent) were family 2. Moreover, because 9 (10.1 percent) isolates were of positive reactions for both, families 1 and 2 primers, the potential coverage of PspA vaccine was 98.9 percent. PspA families were not associated with age group, source of isolates, or penicillin susceptibility. However, the relative distribution of family 1 isolates to family 2 isolates was significantly different over capsular serotypes. Conclusion : The finding that 98.9 percent of Korean isolates belonging to PspA families 1 and 2 support the hypothesis that a human PspA vaccine covering a few PspA families could be broadly effective. The monitoring of the PspA families derived from large population-based isolates will be necessary in the context of vaccine development.

Changes and Challenges in the Concept of Industrial Accident Insurance in Korea (산업재해 인정 형태 변화와 보상체계 합리화 연구)

  • Kim, Jin-Soo;Ra, Ji-Hun;Lee, Seong-Young
    • Korean Journal of Social Welfare
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    • v.59 no.3
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    • pp.59-73
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    • 2007
  • The compensation system in industrial accident insurance is systemized with "either receiving all or no benefits at all" according to "admited or denied as an industrial accident". Therefore, they are centered on the decision as "industrial accident" or "non-industrial accident", but judging between the two is very complicated, and has inherent conflicting factors. In the early stage of industrialization, industrial accident compensation was based on the indemnity liability for employer's faults. In order to be compensated any damage, the injured worker should prove that the accident was not due to his or her faults. However it was very difficult for injured worker or his or her family to prove the employer's faults, so it was almost impossible to get compensation. Thereafter industrialization progress and improvement of workers' political status lead to conversion from principle of liability with employer's faults to principle of liability without employer's faults. In addition to that, coverage of industrial accident compensation was also expanded. This improvement strengthened the benefit payment principle of "All or Nothing". Even though the "All or Nothing" principle provokes tremendous criticism, the reason why it's difficult for industrialized countries to adopt partial compensation system, is that partial compensation system worsens the administrative hardship, therefore industrialized countries overcome the restrictions of the "All or Nothing" principle with making balance in provisions for any risk to some extent. However, in Korea because the general compensation system for covering medical cost and income loss from accidents, is not equipped, it could be possible to cause acute conflicts with regard to coverage of industrial accidents. Therefore it is required to improve the industrial accident insurance with the acceptance of the significance and logic of discriminated compensation, and create the integrated compensation system in the long run.

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Changes in Compositions of Liquor Fractions Distilled from Samil-ju with Various Distillation Conditions (증류조건에 따른 삼일주 증류액의 성분변화)

  • Min, Young-Kyoo;Yun, Hyang-Sik;Jeong, Heon-Sang;Jang, Yun-Sik
    • Korean Journal of Food Science and Technology
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    • v.24 no.5
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    • pp.440-446
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    • 1992
  • Samil-ju, the traditional Korean rice wine was brewed and distilled using different columns (unpacked and packed) at different pressure (760, 460, 260 mmHg). Fractions of distillate were collected and analyzed. The sample wine, Samil-ju showed the following compositions; ethanol 14%, total acidity 16.2 g/100 ml, reducing sugar 7.9 mg/ml, total sugar 8.4 mg/ml, acetaldehyde 6 ppm, fusel oil acetaldehyde and ethyl acetate 6 ppm. As distillation proceeds, contents of ethanol, methanol, fusel oil, acetaldehyde and ethyl acetate were decreased but total acidity was increased. Generally at reduced pressure, all the constituents but total acidity showed more decrease than those at atmospheric pressure. In the 1st, 2nd and 3rd fractions of the distillate, ethanol contents were maintained at about 70% but those contents decreased abruptly to below 50% from the 5th fraction. Sixteen sensory characteristics were identified as quality factors of distillate. Among them, four characteristics were identified as aroma properties, seven as tastes and five as aftertastes. Nuruk and cooling flavor were considered as important factors which affect greatly the sensory quality of distillate. Among various fractions, the 2nd, 3rd and 4th fractions obtained from unpacked column at 260 mmHg showed the highest score in the overall quality. The compositions of these fractions were ranged as follows; methanol $24{\sim}36\;ppm$, total acidity $0.21{\sim}0.29\;g/100\;ml$, fusel oil 657-1340 ppm, acetaldehyde $12{\sim}41\;ppm$, and ethylacetate $22{\sim}311\;ppm$, respectively.

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액체로켓의 노즐 삭마에 대한 실험적 연구

  • Kim, Jong-Wook;Park, Hee-Ho;Kim, Sun-Gi;Kim, Yoo
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2000.04a
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    • pp.21-21
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    • 2000
  • 통상적으로 액체로켓의 노즐은 재생냉각에 의해 고온의 연소가스로부터 보호된다. 그러나 재생냉각의 경우, 시스템에 상당한 투자가 요구되며, 잦은 엔진 결함의 원인을 제공하기도 한다. 최근 들어 액체로켓에 재생냉각을 사용하지 않고, 연소실과 노즐 보호를 위해 삭마재료가 사용되고 있다. 노즐재료에 대한 삭마량과 삭마형상 연구를 위해 500회 이상의 연소실험이 수행되었다. 그러나 연소실험을 통한 삭마특성은 전혀 예측할 수 없는 방향으로 진행되고 있으며, 실험에 사용된 액체로켓의 작동범위가 실제 로켓과 거의 유사하다는 것을 감안한다면, 삭마재질을 로켓에 적용하기 위해서는 상당한 주의가 필요할 것으로 판단된다. 실험변수는 추진제의 공급 순서, 인젝터의 형상, 점화기의 위치, 그리고 액체산소의 공급온도이다.

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고성능 콘크리트의 정의 및 교량 바닥판의 실용화

  • 정원기;이형준
    • Magazine of the Korea Concrete Institute
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    • v.11 no.3
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    • pp.70-84
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    • 1999
  • HPC를 사용한 장기수명 바닥판 콘크리트의 시공에 관한 4가지 접근방법을 제시하였다. Nebraska, New Hampshire, Texas 그리고 Virginia 등 4개주의 프로젝트에서 보면 아래와 같이 여러 가지 유사성을 알 수 있었다. $\cdot$ HPC의 사용은 장기 수명의 교량 바닥판을 건설하기 때문에 life cycle cost와 유지관리비의 감소가 예상된다. $\cdot$ 교량 바닥판에 대한 HPC의 중요성은 더 큰 강도보다는 내구성과 시공성을 일관성있게 양호하게 개선한다는 것이다. $\cdot$ 그 지역의 재료와 기존의 방법을 가능한 최대한 범위로 사용한다. $\cdot$ 많은 실험실 및 현장 시험 배합표가 개발되었고 배합되었다. 성능 특성은 혼합 재료의 형태, 상품 및 배합에 따라 다르게 나타났다. $\cdot$ 향상된 성질을 갖는 균일하고 일관성 있는 제품의 사용에 덧붙여 적절한 시공 기술은 장기 수명의 콘크리트 구조물을 위해서는 필수적이다. $\cdot$ 알카리-골재 반응을 갖고 있는 지역이나 높은 황산염을 갖고 있는 지역과 같이 특별한 문제점이 예상되는 지역에서는 화학적 내구성을 검토하기 위해 별도의 실험이 필요하다. $\cdot$ 현장에서 소요의 성능특성을 얻기 위해서는 시작부터 모든 분야 사이의 원활한 의견 교환과 협력이 요구된다.

A Real-time Frontal Face Detection Based on SRC (SRC 기반의 실시간 정면 얼굴 탐지)

  • Kang, Bong-Su;Oh, Seung-Geun;Lee, Jong-Uk;Park, Dae-Hee
    • Proceedings of the Korean Information Science Society Conference
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    • 2011.06a
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    • pp.458-461
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    • 2011
  • 본 논문에서는 요주의 인물 식별 시스템의 서브시스템으로 SRC 기반의 실시간 정면 얼굴 탐지 시스템을 제안한다. 제안된 시스템은 개선된 피부색 탐지기를 통해 실시간으로 입력되는 영상의 이미지로부터 얼굴 탐지 범위를 축소하고, 단계형 분류기를 통해 얼굴 여부를 빠른 속도로 탐지함으로써 실시간 탐지가 가능케 하였다. 또한 최근 얼굴 인식 분야에서 성공적인 업적을 보여주고 있는 신호 처리 분야의 SRC를 이용하여 정면 얼굴, 비정면 얼굴, 그리고 비얼굴을 분류하여 정면 얼굴만을 출력함으로써 정면 얼굴 탐지율을 높힌다. 공인된 벤치마킹 데이터인 FEI Face Database을 사용하여 제안된 SRC 기반의 정면 얼굴 탐지 시스템의 성능을 실험적으로 평가한다.