• Title/Summary/Keyword: Selective recovery

Search Result 259, Processing Time 0.032 seconds

Selective Redo recovery scheme for fine-Granularity Locking in Database Management (데이터베이스 관리 시스템에서 섬세 입자 잠금기법을 위한 선택적 재수행 회복기법)

  • 이상희
    • Journal of the Korea Society of Computer and Information
    • /
    • v.6 no.2
    • /
    • pp.27-33
    • /
    • 2001
  • In this thesis, we present a simple and efficient recovery method, called ARIES/SR(ARIES/Selective Redo) which is based on ARIES(Algorithm for Recovery and Isolation Exploiting Semantics) ARIES performs redo for all updates done by either nonloser transaction or loser transaction, and thus significant overhead appears during restart after a system failure. To reduce this overhead, we propose ARIES/SR recovery algorithm. In this algorithm, to reduce the redo operations, redo is performed, using log record for updates done by only nonloser transaction. Also selective undo is performed. using log record for update done by only loser transaction for reducing recovery operation.

Selective Plugging Strategy Based Microbial Enhanced Oil Recovery Using Bacillus licheniformis TT33

  • Suthar, Harish;Hingurao, Krushi;Desai, Anjana;Nerurkar, Anuradha
    • Journal of Microbiology and Biotechnology
    • /
    • v.19 no.10
    • /
    • pp.1230-1237
    • /
    • 2009
  • The selective plugging strategy of Microbial Enhanced Oil Recovery (MEOR) involves the use of microbes that grow and produce exopolymeric substances, which block the high permeability zones of an oil reservoir, thus allowing the water to flow through the low permeability zones leading to increase in oil recovery. Bacillus licheniformis TT33, a hot water spring isolate, is facultatively anaerobic, halotolerant, and thermotolerant. It produces EPS as well as biosurfactant and has a biofilm-forming ability. The viscosity of its cell-free supernatant is $120\;mPa{\cdot}s$ at $28^{\circ}C$. Its purified EPS contained 26% carbohydrate and 3% protein. Its biosurfactant reduced the surface tension of water from 72 to 34 mN/m. This strain gave $27.7{\pm}3.5%$ oil recovery in a sand pack column. Environmental scanning electron microscopy analysis showed bacterial growth and biofilm formation in the sand pack. Biochemical tests and Amplified Ribosomal DNA Restriction Analysis confirmed that the oil recovery obtained in the sand pack column was due to Bacillus licheniformis TT33.

A Band-Selective CPPLL for Fast Acquisition time (빠른 Acquisition 시간을 위한 Band-Selective CPPLL)

  • 류상하;김재완;김수원
    • Proceedings of the IEEK Conference
    • /
    • 2000.06e
    • /
    • pp.85-88
    • /
    • 2000
  • This paper describes a Band-Selective Charge-Pump PLL(CPPLL) for clock recovery and clock generator. The proposed PLL satisfies fast acquisition time and low jitter characteristics simultaneously by reducing initial frequency error. The acquisition time of the designed Band-Selective CPPLL can be decreased down to 55% of a conventional CPPLL.

  • PDF

Treatment of organic dye solutions by electrodialysis

  • Majewska-Nowak, Katarzyna M.
    • Membrane and Water Treatment
    • /
    • v.4 no.3
    • /
    • pp.203-214
    • /
    • 2013
  • Laboratory tests were performed to determine the efficiency of dye solution desalination by electrodialysis. The study involved anionic dye and mineral salt recovery by obtaining two streams from a salt and dye mixture - dye-rich solution and salt solution. A standard anion-exchange and cation-exchange membranes or monovalent selective anion-exchange membranes were used in the ED stack. It was found that the separation efficiency was strongly dependent on the dye molecular weight. The best results for standard ion-exchange membranes were achieved for the desalination of Direct Black solution. Furthermore, the obtained results implied that the application of monovalent selective anion-exchange membranes improved the recovery of dye and salt solutions - the dye concentration in the diluate remained constant irrespective of the molecular weight of anionic dyes, whereas the salt recovery remained very high (99.5%).

Comparison of Bifidobacteria Selective Media for the Detection of Bifidobacteria in Korean Commercial Fermented Milk Products

  • Kim, Eung-Ryool;Cho, Young-Hee;Kim, Yong-Hee;Park, Soon-Ok;Woo, Gun-Jo;Chun, Ho-Nam
    • Food Science of Animal Resources
    • /
    • v.30 no.1
    • /
    • pp.154-162
    • /
    • 2010
  • This study was carried out to compare the efficacy and selectivity of TOS and BS media for enumeration of bifidobacteria in commercial fermented milk products. First, bifidobacteria was isolated from 20 fermented milk products, and all isolated bifidobacteria were identified by genomic technology as Bifidobacterium lactis. The two media significantly differed from each other with regard to the recovery of B. lactis, that is, the recovery of this organism was as much as 6 logs lower on BS medium than on TOS. When the concentration of BS solution (mixture of paromomycin sulfate, neomycin, sodium propionate, and lithium chloride) used in BS medium was reduced to 50% (BS50), a relatively high percentage recovery of bifidobacteria from pure cultures was achieved. Susceptibility tests to antibiotics and tests for selective agents for the isolated bifidobacteria and lactic acid bacteria were conducted. The BS solution inhibited some lactic acid bacteria and Bifidobacterium species, while mupirocin (MU) suppressed the growth of all tested lactic acid bacteria but not Bifidobacterium. As compared with BS50 medium, TOS with or without MU showed good bifidobacteria recovery and readily distinguishable colonies; in particular, TOS supplemented with MU had a high selectivity for bifidobacteria. In conclusion, all results suggested that TOS medium with or without MU was found to be suitable for selective enumeration of bifidobacteria from mixed cultures in fermented milk, and better in that capacity than BS medium.

A Selective Recovery Condition of Vanadium from Fly Ash Leach Liquor by UV-Spectrophotometry (UV 분광법을 이용한 중유회 용출액으로부터 바나듐의 선택적 회수 조건)

  • Kim, Da-Bin;Na, Su-Bin;Han, Hyea-Chul
    • Resources Recycling
    • /
    • v.25 no.6
    • /
    • pp.65-72
    • /
    • 2016
  • We studied a selective recovery condition of vanadium (V) from FALL (Fly Ash Leach Liquor) produced at a fossil fuel power station using heavy oil. By applying a spectroscopy to quantify the V in a sample, we identified a concentration range V interfered by on presence of metals such as Ni, Fe Also, the optimal vanadium precipitation rate according to the amount of 5.0M $NH_3$ loaded to the sample, solution pH and stirring time. As a result of the experiment, the maximum selective recovery ratio of V was achieved to be higher than 91.5% when the stirring duration was less than 1 minute at pH 7.0, and $25^{\circ}C$.

Selective Ni Recovery from Spent Ni-Mo-Based Catalysts (니켈-몰리브데늄 성분계 폐촉매로부터 니켈의 선택적 회수)

  • Lee, Tae Kyo;Han, Gi Bo;Yoon, Suk Hoon;Lee, Tae Jin;Park, No-Kuk;Chang, Won Chul
    • Applied Chemistry for Engineering
    • /
    • v.19 no.6
    • /
    • pp.668-673
    • /
    • 2008
  • The objective of this study is to optimize the leaching conditions of sequential leaching and extracting processes for selective Ni recovery from spent Ni-Mo-based catalyst. The selective Ni recovery process consists of two processes of leaching and extracting process. In this 2-step process, Ni component is dissolved from solid spent Ni-Mo-based catalyst into leaching agent in leaching process and sequentially extracted to Ni complex with an extracting agent in the extracting process. The solutions of nitric acid ($HNO_3$), ammonium carbonate ($(NH_4)_2CO_3$) and sodium carbonate ($Na_2CO_3$) were used as a leaching agent in leaching process and oxalic acid was used as an extracting agent in extracting process. $HNO_3$ solution is the most efficient leaching agent among the various leaching agent. Also, the optimized leaching conditions for the efficient and selective Ni recovery were the leaching temperature of $90^{\circ}C,\;HNO_3$ concentration of 6.25 vol% and elapsed time of 3 h. As a result, Nickel oxalate having the highest yield of 88.7% and purity of 100% was obtained after sequentially leaching and extracting processes under the optimized leaching conditions.

Toward high recovery and selective leaching of zinc from electric arc furnace dust with different physicochemical properties

  • Lee, Han Saem;Park, Da So Mi;Hwang, Yuhoon;Ha, Jong Gil;Shin, Hyung Sang
    • Environmental Engineering Research
    • /
    • v.25 no.3
    • /
    • pp.335-344
    • /
    • 2020
  • This work describes highly efficient recovery and selective leaching of Zn from electric arc furnace dust (EAFD) with different physicochemical properties, induced by acid leaching at ambient conditions. The chemical compositions, mineralogical phases, and particle sizes of the EAFDs were analyzed and compared. The effects of leaching time, liquid/solid ratio, acid type, and acid concentration on the selective leaching of Zn were also studied. The EAFD with high Fe/Zn ratio (> 1, EAFD3) was richer in ZnFe2O4 and exhibited larger particle size than samples with low Fe/Zn ratio (< 1, EAFD1,2). ANOVA analysis revealed that the Fe/Zn ratios of the EAFDs also have a significant effect on Zn extraction (p < 0.005). Selective leaching of Zn with minimum Fe dissolution was obtained at pH > 4.5, regardless of other parameters or sample properties. The maximum Zn extraction rate obtained by the pH control was over 97% for EAFD1 and EAFD2, 76% for EAFD3, and 80% for EAFD4. The present results confirm that the Fe/Zn ratio can be used to identify EAFDs that permits facile and high-yield Zn recovery, and pH can be used as a process control factor for selective leaching of Zn regardless of any differences in the properties of the EAFD sample.

Adaptive Selective Compressive Sensing based Signal Acquisition Oriented toward Strong Signal Noise Scene

  • Wen, Fangqing;Zhang, Gong;Ben, De
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.9 no.9
    • /
    • pp.3559-3571
    • /
    • 2015
  • This paper addresses the problem of signal acquisition with a sparse representation in a given orthonormal basis using fewer noisy measurements. The authors formulate the problem statement for randomly measuring with strong signal noise. The impact of white Gaussian signals noise on the recovery performance is analyzed to provide a theoretical basis for the reasonable design of the measurement matrix. With the idea that the measurement matrix can be adapted for noise suppression in the adaptive CS system, an adapted selective compressive sensing (ASCS) scheme is proposed whose measurement matrix can be updated according to the noise information fed back by the processing center. In terms of objective recovery quality, failure rate and mean-square error (MSE), a comparison is made with some nonadaptive methods and existing CS measurement approaches. Extensive numerical experiments show that the proposed scheme has better noise suppression performance and improves the support recovery of sparse signal. The proposed scheme should have a great potential and bright prospect of broadband signals such as biological signal measurement and radar signal detection.

Sequential and Selective Recovery Mechanism for Value Misprediction (값 예측 오류를 위한 순차적이고 선택적인 복구 방식)

  • 이상정;전병찬
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.31 no.1_2
    • /
    • pp.67-77
    • /
    • 2004
  • Value prediction is a technique to obtain performance gains by supplying earlier source values of its data dependent instructions using predicted value of a instruction. To fully exploit the potential of value speculation, however, the efficient recovery mechanism is necessary in case of value misprediction. In this paper, we propose a sequential and selective recovery mechanism for value misprediction. It searches data dependency chain of the mispredicted instruction sequentially without pipeline stalls and adverse impact on clock cycle time. In our scheme, only the dependent instructions on the predicted instruction is selectively squashed and reissued in case of value misprediction.