• Title/Summary/Keyword: SS

Search Result 3,781, Processing Time 0.025 seconds

The study of chemical treatment of pulp mill bleaching waste liquor using sea water (해수를 이용한 펄프공장 폐액의 화학적 처리에 관한 연구)

  • 정병곤;이헌모;윤종호
    • Journal of environmental and Sanitary engineering
    • /
    • v.12 no.1
    • /
    • pp.39-48
    • /
    • 1997
  • The study was conducted to know the possibility that the removal efficiency of organic and suspended solids(SS) could be increased by suppling of sea water and the optimum amount of sea water to be supplied treat bleaching waste water by lime coagulation settlement at pulp mill process. When the lime dosage was increased, the removal efficiency of COD and SS in the waste water was increased based on the removal efficiency of COD and SS. The lime dosage and removal efficiency was increased proportionally with the lime concentration of 4,000 mg/l, but the increase of removal efficiency was presented slightly above the 4,000mg/l. It was evaluated that the removal efficiencies of COD and SS could be increased and the requirement of lime dosage could be decreased by the sea water supplement. The removal efficiency of SS was most increased when the sea water supplement was 10% or more in the waste water. The removal efficiencies of COD was the best at 4% sea water excepting the dilution efficiency by sea water supplement.

  • PDF

Self-Sealing & Self-Healing Landfill Liner

  • Caijun Shi
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
    • /
    • 1997.11a
    • /
    • pp.35-50
    • /
    • 1997
  • 쓰레기 매립장의 오수 침출 방지를 목적으로 그간 차수층이 시공되었으나 기존의 차수재는 그 성능상 많은 문제점을 내포하고 있었다. 이게 본 고에서는 '자가 형성' 및 '자가 치유'기능을 가진 SS/SH 차수층에 관하여 실내 시험 및 수도권 매립지(3공구)를 대상으로 현장 시험시공을 실시한 결과에 관해서 기술하였다. 두 시험을 통하여 SS/SH 차수층은 쓰레기 매립장 차수재로써 필요한 기준강도를 충족시키는가 하면 투수계수도 기준치를 만족시키는 낮은 수치를 나타내는 등 우수한 기능성을 충분하게 입증하였다. 무엇보다, 쓰레기 매립장에서 일반적으로 발생하는 차수층 손상에 대한 '탁월한 치유기능'을 가지고 있음으로 차수층 보수비가 전혀 필요없다는 점에서 대단히 경제적이라고 판단되었기에, 기능성과 경제성을 확보한 이 SS/SH 공법을 본공사에 적용할 수 있게 된 것이다.

  • PDF

Performance of a hybrid DS/SFH spread spectrum system over fading channel in the presence of multiple tone jamming (다중 톤방해신호가 존재하는 페이딩 전송로에서 DS/SFH 복합 확산대역시스템의 성능분석)

  • 박찬범;이재홍
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.33A no.11
    • /
    • pp.10-18
    • /
    • 1996
  • In this paper, performance of a hybrid direct-sequency/slow-frequency-hopped (DS/SFH) spread-spectrum (SS) system with coherent BPSK modulation is analyzed. The bit error probability is derived over a frequency=-selective rician fading channel in the presence of multiple tone jamming. The fading channel is modeled as the wide-sense stationary uncorrelated scattering (WSSUS) model. Numerical evaluations are presented for some combinations of system parameters. The performance of a hybrid DS/SFH SS system is shown to be inferior to that of a ure DS SS system at low jamming-to-signal power ratio (JSR). At high JSR, the performance of a pure DS SS system is shown to be the smae as the worst case performance of a hybrid DS/SFH SS system.

  • PDF

An Experimental Study of Concussion Blasting for Structural Steel (구조용 강재에 대한 폭파절단실험 연구)

  • Yang, Hyung-Sik;Jang, Hyong-Doo;Ko, Young-Hun;Kim, Sung-Jun;Moon, Hee-Sook
    • Explosives and Blasting
    • /
    • v.29 no.1
    • /
    • pp.27-33
    • /
    • 2011
  • Concussion shots were conducted for SS400, a general structural steel, and SM490, a structural steel for welding, using TNT, which is used as a standard explosive. The ability to cut the steels was compared for different combinations of charges and materials. The results show that the amount of explosives used for SM490 requires more 30% than SS400.

Evolution of Cube Texture in the Nickel-Silver-Stainless steel Multi-layer Sheet

  • Lee, Hee-Gyoun;Jung, Yang-Hong;Hong, Gye-Won
    • Progress in Superconductivity
    • /
    • v.1 no.1
    • /
    • pp.51-55
    • /
    • 1999
  • A Ni/Ag/Stainless steel 310S(SS310S) multi-layer sheet has been fabricated by a combination of vacuum brazing, cold rolling and texture annealing processes. After heat-treating the thin Ni/Ag/SS310S multi-layer sheet at $900^{\circ}C$ for 2h, development of (100)<001>cube texture on Ni surface was revealed by (111) pole figure. Quantitative chemical analysis was made by EPMA for the cross-section of the Ni/Ag/SS310S multi-layer sheet. EPMA results showed that Ag diffusion into the Ni layer, which may suppress the cube texture development, was negligible. A small amount of Cr atoms were detected in the Ni layer. It showed that Ag can be used as a chemical barrier of alloying element atoms in Ni layer for the Ni/Ag/SS310S multi-layer sheet and a strong cube texture was developed for the Ni layer in the Ni/Ag/SS310S multi-layer sheet.

  • PDF

A Study on the Performance Improvement of DM-SS Watermarking with RS code in OFDM/QPSK Wireless channel Environment (OFDM/QPSK 무선 채널 환경에서 RS 부호화 기법을 적용한 DM-SS 워터마킹 성능 개선에 관한 연구)

  • Jo Song-Back;Kim Ji-Woong;Kang Heau-Jo
    • Journal of Digital Contents Society
    • /
    • v.5 no.4
    • /
    • pp.316-320
    • /
    • 2004
  • In this paper, we propose OFDM/QPSK technique for copyright protection of image data to insert watermark. And, we improve performance of restoration watermark by Reed-Solomon coding that robust burst error. In here, we consider several factors about external effect of image over OFDM/QPSK transmission system.

  • PDF

Transmission Characteristics of FFH-SS Communication System in Fading Media (페이딩 매질에서 대역확산 주파수도약 통신시스템의 전송특성)

  • Kim, Won-Hu;Jeon, Gye-Seok
    • The Journal of the Acoustical Society of Korea
    • /
    • v.6 no.1
    • /
    • pp.5-14
    • /
    • 1987
  • In this paper, the transmission characteristics of a frequency-hopped spread spectrum communication system operating in the presence of both time and frequency-selective fading channel is presented. The receiver is a binary noncoherent matched-filter FFH-SS system with square-law combiner. The probability of error to the variations of the parameters such as signal-to-noise ratio, selectivity of a channel, and power ratio is derived with the use of diversity concept without considering the data rate. The analysis of the data for probability of error shoves that the performance of FFH-SS system in time-selective fading channel is better than in frequency-selective fading channel.

  • PDF

Analysis of relationship between SS, COD, and T-P in rural area (농촌유역에서의 SS, COD 및 T-P간의 상관관계 분석(지역환경 \circled1))

  • 함종화;윤춘경
    • Proceedings of the Korean Society of Agricultural Engineers Conference
    • /
    • 2000.10a
    • /
    • pp.525-530
    • /
    • 2000
  • The loss of soil and nutrients from land surfaces to surface water supplies continues to be an important source of nonpoint source pollution. This study was initiate to develop an empirical relationship among the contaminants. SS, COD, T-N, and T-P were collected from agricultural surface water quality studies carried out in Hwasung-Gun, Kyonggi-Do. Correlation analysis, regression analysis, and reliability analysis were conducted. The regression equations were developed between SS and COD, SS and T-P, COD and T-P, and the resulting r$\^$2/ value was over 0.78. The regression equation enables a reasonable prediction of phosphorus concentration and COD concentration for known suspended solid concentration.

  • PDF

Correlation of SS to COD and T-P in Tributary to a Reservoir (담수호에 유입되는 하천수에서의 SS 와 COD 및 T-P 와의 상관관계)

  • 우선호;윤춘경
    • Proceedings of the Korean Society of Agricultural Engineers Conference
    • /
    • 1999.10c
    • /
    • pp.715-720
    • /
    • 1999
  • When it rains, soil erosion occurs and soil particles move into the reservoirs or stream . Nutrients and contaminants, which are adsorbed on soil particles, flow into waterbody and are leached into water. Then they effect on water quality and eutrophicaltion of reservoirs. In this study , corrleation of SS to COD was surveyed , and that of SS to T-P was also done. R2 values in wet period were almost over 0.8, but were very low in dry period . THis shows that concentrations of COD and T_P will be assumed by using SS concentrations in wet period in stream.

  • PDF

Development of Protein Secretion System using Type III Secretion System of Salmonella (Salmonella Type III Secretion System을 이용한 단백질 분비시스템 개발)

  • Dinh, Le Tam Vo;Hong, Soon-Ho
    • KSBB Journal
    • /
    • v.24 no.4
    • /
    • pp.393-396
    • /
    • 2009
  • New protein secretion system was developed using Type III Secretion System of Salmonella. N-terminal region of SlrP and SptP effector proteins were fused with TliA and EstA-P lipases by overlapping PCR. Lipase activity of Salmonella with SptP-TliA fusion system increased by 2.6 fold compare with wild type Salmonella strain. This result showed that lipase secretion via the T3SS would be a useful protein secretion machinery.