• Title/Summary/Keyword: NBS

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Comparative assessment of urban stormwater low impact strategies equipped with pre-treatment zones (침강지 시설이 조성된 LID 시설의 환경적 영향평가)

  • Yano, K.A.V.;Reyes, N.J.D.G.;Jeon, M.S.;Kim, L.H.
    • Journal of Wetlands Research
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    • v.21 no.2
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    • pp.181-190
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    • 2019
  • Recently, Low impact development techniques, a form of nature-based solutions (NBS), were seen cost-efficient alternatives that can be utilized as alternatives for conventional stormwater management practices. This study evaluated the effectiveness of an infiltration trench (IT) and a small constructed wetland (SCW) in treating urban stormwater runoff. Long-term monitoring data were observed to assess the seasonal performance and cite the advantages and disadvantages of utilizing the facilities. Analyses revealed that the IT has reduced performance during the summer season due to higher runoff volumes that exceeded the facility's storage volume capacity and caused the facility to overflow. On the other hand, the pollutant removal efficiency of the SCW was impacted by the winter season as a result of dormant biological activities. Sediment data also indicated that fine and medium sand particles mostly constituted the trapped sediments in the pretreatment and media zones. Sediments in SCW exhibited a lower COD and TN load due to the phytoremediation and microbiological degradation capabilities of the system. This study presented brief comparison LID facilities equipped with pre-treatment zones. The identified factors that can potentially affect the performance of the systems were also beneficial in establishing metrics on the utilization of similar types of nature-based stormwater management practices.

A New Block Cipher for 8-bit Microprocessor (8 비트 마이크로프로세서에 적합한 블록암호 알고리즘)

  • 김용덕;박난경;이필중
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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    • 1997.11a
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    • pp.303-314
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    • 1997
  • 계산능력이 제한된 8비트 마이크로프로세서에 적합하도록 모든 기본 연산을 8비트 단위로 처리하는, 블록 크기는 64비트, 키 크기는 128비트인, Feistel 구조의 블록 암호 알고리즘을 제시한다. 이 알고리즘의 안전도는 잘 알려진 two-key triple-DES[ANSI86]나 IDEA[Lai92]와 비견할 만하며, 처리속도는 single-DES[NBS77]보다도 10∼20배 빠르다. 본 논문에서는 이 알고리즘의 설계원칙 및 안전성 분석에 대하여 설명하였고, 다른 알고리즘과의 통계적 특성 및 성능에 대해서도 비교하였다.

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Smoke Density Values to the variance of test conditions (시험조건 변화에 따른 연기밀도 특성 조사)

  • Lee Duck-Hee;Lee Cheul Kyu;Jung Woo-Sung;Kim Sun-ok
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.339-345
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    • 2004
  • In this study we reported the Smoke Density values of interior materials of railroad passenger car and investigated the specific smoke density(Ds) by NBS smoke chamber to the variance of some test conditions. First we compared the result of Ds from ISO 5659-2 with that from ASTM E 662 for same material. Secondary studied the Ds value to the variance of specimen shape and thickness and to the variance of other conditions.

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Contemporary Chinese Households' Food Away From Home Expenditure and Becker's Household Production Theory

  • Kim Eon-Jin;Chern Wen S.
    • International Journal of Human Ecology
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    • v.6 no.1
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    • pp.17-28
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    • 2005
  • This study examines factors determining contemporary Chinese households' food away from home (FAFH) expenditures using Becker's household production theory. Data came from the 2000 urban household survey in Guangdong Province, collected by National Bureau of Statistics (NBS) of China. It was revealed that the contemporary urban Chinese wives also substitute their household work by time-saving product, FAFH, as Becker's household production theory postulated. This suggests the important role of time-value (opportunity cost) in determining household FAFH expenditure across the cultures.

Smoke Density Characteristics of the FRP to the variance of test method, resin type and specimen shape (FRP 복합재의 시험조건 변화에 따른 연기 위해성 평가)

  • 이덕희;정우성;김용기;김선옥
    • Proceedings of the KSR Conference
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    • 2002.05a
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    • pp.567-571
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    • 2002
  • In this study we reported the Smoke Density test method of interior panel of railroad passenger car and investigated the specific smoke density(Ds) by NBS smoke chamber to the variance of some test conditions. First we compared the result of Ds from ISO 5659-2 with that from ASTM E662 for same phenol FRP Secondary studied the Ds value to the variance of resin type and to the variance of specimen shape.

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Oxidations of Cyclohexanols by N-Bromosuccinimide and Sodium Hypochlorite

  • Chung, Kyoo-Hyun;Kim, Seong-Jin
    • Bulletin of the Korean Chemical Society
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    • v.7 no.2
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    • pp.111-113
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    • 1986
  • The axial alcohol in trans-3,3,5-trimethylcyclohexanol was oxidized more readily than the equatorial alcohol in cis-3,3,5-trimethylcyclohexanol by NBS in aqueous dioxane. On the contrary, the equatorial alcohol was preferentially oxidized to the axial one by 10% aqueous sodium hypochlorite in the presence of tetrabutylammonium hydrogen sulfate (TBHS). The specificity indicates the presence of two different mechanism. In acidic medium, the cleavage of C-H bond is rate determining step while the reactivity of the alcohol is important in the presence of TBHS. The mechanism in basic medium without TBHS will be discussed.

Stereoselective Halolactonization of$\alpha-Phenylsulfonyl-\gamma,\delta$-Unsaturated Amides

  • Lee, Jae-Wook;Jung, Jin-Hang;Oh, Dong-Young
    • Bulletin of the Korean Chemical Society
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    • v.15 no.10
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    • pp.842-845
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    • 1994
  • Iodine-induced lactonization of ${\alpha}$-Phenylsulfonyl-${\gamma},{\delta}$-Unsaturated Amides provided 2,4-trans-substitued ${\gamma}$-butyrolactones in high selectivity. NBS-or NCS-induced lactonization of N,N-dimethyl-2-(phenylsulfonyl)-4-pentenamide in DME-$H-2O(2:1 vol)$ gave 2-halo-4-(halomethyl)-2-(phenylsulfonyl)-${\gamma}$-butyrolactone.

Halolactonization reaction using N-haloimides

  • Cook, Chae-Ho;Cho, Youn-Sang;Jew, Sang-sup;Suh, Young-Guh;Kang, Eung-Ku
    • Archives of Pharmacal Research
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    • v.6 no.1
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    • pp.45-53
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    • 1983
  • Novel halactolactonizations using NBS (2), NIS(3), and NSP(4) in dry DMF were found to be the most reasonable and efficient procedures. The participation of X as the cylization initiator could be clarly rationalized by experimental results and the regioselectivities of formed halolactones were reasonably elucidated by weakly bridged carbonium ion intermediate.

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A Study on Stabilized CdS-CdSe Red Stain part III, Application of $ZrSiO_4-Cd(SxSe_{1-x})$ Stain to Ceramic Body (안정화 CdS-CdSe계 채료에 관한 연구 제3보 $ZrSiO_4-Cd(SxSe_{1-x})$채료의 응용연구)

  • 이종근;김종옥
    • Journal of the Korean Ceramic Society
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    • v.24 no.2
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    • pp.155-160
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    • 1987
  • The investigation includes the application of $ZrSiO_4-Cd(SxSe_{1-x})$stain to ceramic body. The currently developed stain was compared to the commercially available stain in applying to ceremic glaze. Two stains (currently developed and commecially available) were mixed with frits and applied to ceramic tiles. The tiles were fired at 850 to 120$0^{\circ}C$ and tested by colorimeter in X.Y.Z. axis of the wavelength ranging from 580nm to 650nm. Applicability 18 stains to ceramic body was investigated by ISCC-NBS of Munsell color nomenclature. $ZrSiO_4-Cd(SxSe_{1-x})$stain is as good as V and Pr series stain in mixing composition of frits 9 to 1. It maintains red color at 100$0^{\circ}C$ in the mixture of frits, and shows as the strong acid resistance stain.

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Joint Operation of ABS with Power Control and Derivation of an Effective ABS Ratio for LTE Hetnet Environments (LTE-A 이종망 환경에서 ABS와 Power Control의 동시적용과 ABS 비율 도출)

  • Sung, No-Hoon;Choi, Young-June;Jang, Ji-Woong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.12
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    • pp.2381-2388
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    • 2015
  • It has been known that interference occurs between macrocell ans small-cell base stations in a heterogeneous network (HetNet) of LTE-A. For solving this problem, 3GPP suggested eICIC (Enhanced Inter Cell Interference Coordination) that includes ABS (Almost Blank Subframe) and power control. This paper proposes to use ABS with power control and derives an effective ABS ratio as a function of the number of users and HeNBs. Through simulation, we confirm that integration of ABS and power control can mitigate interference than using ABS only. Furthermore, we verify that an effective ABS ratio is different depending on the number of users and HeNBs.