Journal articles: 'BIT Index'

1

Rinfret, Denis, Patrick O'Neil, and Elizabeth O'Neil. "Bit-sliced index arithmetic." ACM SIGMOD Record 30, no. 2 (June 2001): 47–57. http://dx.doi.org/10.1145/376284.375669.

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Adikaram, K. K. L. B., M. A. Hussein, M. Effenberger, and T. Becker. "Multiple Memory Structure Bit Reversal Algorithm Based on Recursive Patterns of Bit Reversal Permutation." Mathematical Problems in Engineering 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/827509.

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With the increasing demand for online/inline data processing efficient Fourier analysis becomes more and more relevant. Due to the fact that the bit reversal process requires considerable processing time of the Fast Fourier Transform (FFT) algorithm, it is vital to optimize the bit reversal algorithm (BRA). This paper is to introduce an efficient BRA with multiple memory structures. In 2009, Elster showed the relation between the first and the second halves of the bit reversal permutation (BRP) and stated that it may cause serious impact on cache performance of the computer, if implemented. We found exceptions, especially when the said index mapping was implemented with multiple one-dimensional memory structures instead of multidimensional or one-dimensional memory structure. Also we found a new index mapping, even after the recursive splitting of BRP into equal sized slots. The four-array and the four-vector versions of BRA with new index mapping reported 34% and 16% improvement in performance in relation to similar versions of Linear BRA of Elster which uses single one-dimensional memory structure.

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Miska, S., J. Rajtar, and F. Luo. "Type Curves for Predicting Directional Tendencies of Simple Bottom-Hole Assemblies." Journal of Energy Resources Technology 120, no. 3 (September 1, 1998): 193–200. http://dx.doi.org/10.1115/1.2795035.

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The paper provides solutions for predicting directional tendencies of slick and single stabilizer bottom-hole assemblies (BHA) in curved boreholes. Solutions are derived in a curvilinear system of coordinates in a dimensionless form. These solutions are presented in the form of type curves. Type curves allow for quick evaluation of directional tendencies of a given BHA by providing values of side force and tilt angle at the bit. Using these values an anticipated direction of bit displacement is evaluated, using concepts of formation anisotropy index (FAI) and bit anisotropy index (BAI). Procedures are illustrated by examples of evaluation of side force and tilt at the bit for a slick and single stabilizer BHA. The resulting bit displacements are calculated assuming formation anisotropy and drill bit directional tendencies (FAI and BAI). The results derived from type curves are in agreement with computer simulated data. The comparison shows that application of graphical solutions (type curves) yields only slight error that can be ignored for practical purposes.

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CHLAMTÁČ, EDEN, and ISHAY HAVIV. "Linear Index Coding via Semidefinite Programming." Combinatorics, Probability and Computing 23, no. 2 (November 29, 2013): 223–47. http://dx.doi.org/10.1017/s0963548313000564.

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In theindex codingproblem, introduced by Birk and Kol (INFOCOM, 1998), the goal is to broadcast ann-bit word tonreceivers (one bit per receiver), where the receivers haveside informationrepresented by a graphG. The objective is to minimize the length of a codeword sent to all receivers which allows each receiver to learn its bit. Forlinearindex coding, the minimum possible length is known to be equal to a graph parameter calledminrank(Bar-Yossef, Birk, Jayram and Kol,IEEE Trans. Inform. Theory, 2011).We show a polynomial-time algorithm that, given ann-vertex graphGwith minrankk, finds a linear index code forGof lengthÕ(nf(k)), wheref(k) depends only onk. For example, fork= 3 we obtainf(3) ≈ 0.2574. Our algorithm employs a semidefinite program (SDP) introduced by Karger, Motwani and Sudan for graph colouring (J. Assoc. Comput. Mach., 1998) and its refined analysis due to Arora, Chlamtac and Charikar (STOC, 2006). Since the SDP we use is not a relaxation of the minimization problem we consider, a crucial component of our analysis is anupper boundon the objective value of the SDP in terms of the minrank.At the heart of our analysis lies a combinatorial result which may be of independent interest. Namely, we show an exact expression for the maximum possible value of the Lovász ϑ-function of a graph with minrankk. This yields a tight gap between two classical upper bounds on the Shannon capacity of a graph.

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JPT staff, _. "Drilling Index: A New Approach to Bit Performance Evaluation." Journal of Petroleum Technology 49, no. 12 (December 1, 1997): 1325. http://dx.doi.org/10.2118/1297-1325-jpt.

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Huang, Shuanglin, Qiongying Tan, Yingyang Chen, and Bingli Jiao. "An Index-Bit Enabled Transmission Scheme With Dynamic Balancing." IEEE Communications Letters 24, no. 11 (November 2020): 2431–34. http://dx.doi.org/10.1109/lcomm.2020.3007186.

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Xiao, Lixia, Da Chen, Ibrahim A. Hemadeh, Pei Xiao, and Tao Jiang. "Graph Theory Assisted Bit-to-Index-Combination Gray Coding for Generalized Index Modulation." IEEE Transactions on Wireless Communications 19, no. 12 (December 2020): 8232–45. http://dx.doi.org/10.1109/twc.2020.3020692.

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Al-Bahadili, Hussein, and Saif Al-Saab. "Development of a Novel Compressed Index-Query Web Search Engine Model." International Journal of Information Technology and Web Engineering 6, no. 3 (July 2011): 39–56. http://dx.doi.org/10.4018/jitwe.2011070103.

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In this paper, the authors present a description of a new Web search engine model, the compressed index-query (CIQ) Web search engine model. This model incorporates two bit-level compression layers implemented at the back-end processor (server) side, one layer resides after the indexer acting as a second compression layer to generate a double compressed index (index compressor), and the second layer resides after the query parser for query compression (query compressor) to enable bit-level compressed index-query search. The data compression algorithm used in this model is the Hamming codes-based data compression (HCDC) algorithm, which is an asymmetric, lossless, bit-level algorithm permits CIQ search. The different components of the new Web model are implemented in a prototype CIQ test tool (CIQTT), which is used as a test bench to validate the accuracy and integrity of the retrieved data and evaluate the performance of the proposed model. The test results demonstrate that the proposed CIQ model reduces disk space requirements and searching time by more than 24%, and attains a 100% agreement when compared with an uncompressed model.

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Buckles, L. K., J. W. H. Weijers, D. Verschuren, C. Cocquyt, and J. S. Sinninghe Damsté. "Short-term variability in the sedimentary BIT index of Lake Challa, East Africa over the past 2200 years: validating the precipitation proxy." Climate of the Past Discussions 11, no. 2 (April 2, 2015): 1177–218. http://dx.doi.org/10.5194/cpd-11-1177-2015.

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Abstract. The branched vs. isoprenoid index of tetraethers (BIT index) in Lake Challa sediments has been applied as a monsoon precipitation proxy on the assumption that the primary source of branched tetraether lipids (brGDGTs) was soil washed in from the lake's catchment. However, water column production has since been identified as the primary source of brGDGTs in Lake Challa, meaning that there is no longer a clear mechanism linking BIT index variation and precipitation. Here we investigate BIT index variation and GDGT concentrations at a decadal resolution over the past 2200 years, in combination with GDGT data from profundal surface sediments and 45 months of sediment-trap deployment. The 2200 year record reveals high-frequency variability in GDGT concentrations, and therefore the BIT index. Also surface sediments collected in January 2010 show a distinct shift in GDGT composition relative to those collected in August 2007. Increased bulk flux of settling particles with high Ti / Al ratios during March–April 2008 reflect an event of high detrital input to Lake Challa, concurrent with intense precipitation at the onset of the principal rain season that year. Although brGDGT distributions in the settling material are initially unaffected, this soil erosion event is succeeded by a large diatom bloom in July–August 2008 and a concurrent increase in GDGT-0 fluxes. Near-zero crenarchaeol fluxes indicate that no thaumarchaeotal bloom developed during the subsequent austral summer season; instead a peak in brGDGT fluxes is observed in December 2008. We suggest that increased nutrient availability, derived from eroded soil washed into the lake, stimulated both diatom productivity and the GDGT-0 producing archaea which help decompose dead diatoms passing through the suboxic zone of the water column. This disadvantaged the Thaumarchaeota that normally prosper during the following austral summer. Instead, a bloom of supposedly heterotrophic brGDGT-producing bacteria occurred. Episodic recurrence of such high soil-erosion events, integrated over multi-decadal and longer timescales and possibly enhanced by other mechanisms generating low BIT index values in dry years, can explain the positive relationship between the sedimentary BIT index and monsoon precipitation at Lake Challa. However, application elsewhere requires ascertaining the local situation of lacustrine brGDGT production and of variables affecting the productivity of Thaumarchaeota.

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Fatmasari, Diyah, Setiadji Musthofa, and Bedjo Santoso. "EFEKTIFITAS BUAH BIT (BETA VULGARIS) SEBAGAI DISCLOSING SOLUTION (BAHAN IDENTIFIKASI PLAK)." ODONTO : Dental Journal 1, no. 2 (December 1, 2014): 6. http://dx.doi.org/10.30659/odj.1.2.6-9.

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Background: Bit fruit (Beta vulgaris) is plants as group of vegetables, has potencial as a source of natural dyes for food products. In dental health, a coloring agent which has contrast color with teeth is used for dental plaque identification. Disclosing solution is the most common used material for this purpose. Purpose of this study was to identify if bit fruit can substitute disclosing solution as coloring agent for plaque identification. Method: Research design was Quasi Eksperimental Research.with Posttest Only Control Group Design. Samples was 36 elementary students which divided into 2 groups. Group 1 was 18 students given disclosing solution while group 2 was given bit fruit solution. Independent t test was used to determine diferences between two groups. Result: Research results showed mean of plaque index after application of bit fruit and disclosing solution was 3,75 and 2,66 , with independent t-test resulten significancy 0,000 < 0,05. There was differences of plaque index after two group of application. Conclusion: the bit fruit was more effective to determine plaque compared to disclosing solution.

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11

Buckles, Laura K., Dirk Verschuren, Johan W. H. Weijers, Christine Cocquyt, Maarten Blaauw, and Jaap S. Sinninghe Damsté. "Interannual and (multi-)decadal variability in the sedimentary BIT index of Lake Challa, East Africa, over the past 2200 years: assessment of the precipitation proxy." Climate of the Past 12, no. 5 (May 27, 2016): 1243–62. http://dx.doi.org/10.5194/cp-12-1243-2016.

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Abstract. The branched vs. isoprenoid tetraether (BIT) index is based on the relative abundance of branched tetraether lipids (brGDGTs) and the isoprenoidal GDGT crenarchaeol. In Lake Challa sediments the BIT index has been applied as a proxy for local monsoon precipitation on the assumption that the primary source of brGDGTs is soil washed in from the lake's catchment. Since then, microbial production within the water column has been identified as the primary source of brGDGTs in Lake Challa sediments, meaning that either an alternative mechanism links BIT index variation with rainfall or that the proxy's application must be reconsidered. We investigated GDGT concentrations and BIT index variation in Lake Challa sediments at a decadal resolution over the past 2200 years, in combination with GDGT time-series data from 45 monthly sediment-trap samples and a chronosequence of profundal surface sediments.Our 2200-year geochemical record reveals high-frequency variability in GDGT concentrations, and therefore in the BIT index, superimposed on distinct lower-frequency fluctuations at multi-decadal to century timescales. These changes in BIT index are correlated with changes in the concentration of crenarchaeol but not with those of the brGDGTs. A clue for understanding the indirect link between rainfall and crenarchaeol concentration (and thus thaumarchaeotal abundance) was provided by the observation that surface sediments collected in January 2010 show a distinct shift in GDGT composition relative to sediments collected in August 2007. This shift is associated with increased bulk flux of settling mineral particles with high Ti / Al ratios during March–April 2008, reflecting an event of unusually high detrital input to Lake Challa concurrent with intense precipitation at the onset of the principal rain season that year. Although brGDGT distributions in the settling material are initially unaffected, this soil-erosion event is succeeded by a massive dry-season diatom bloom in July–September 2008 and a concurrent increase in the flux of GDGT-0. Complete absence of crenarchaeol in settling particles during the austral summer following this bloom indicates that no Thaumarchaeota bloom developed at that time. We suggest that increased nutrient availability, derived from the eroded soil washed into the lake, caused the massive bloom of diatoms and that the higher concentrations of ammonium (formed from breakdown of this algal matter) resulted in a replacement of nitrifying Thaumarchaeota, which in typical years prosper during the austral summer, by nitrifying bacteria. The decomposing dead diatoms passing through the suboxic zone of the water column probably also formed a substrate for GDGT-0-producing archaea. Hence, through a cascade of events, intensive rainfall affects thaumarchaeotal abundance, resulting in high BIT index values.Decade-scale BIT index fluctuations in Lake Challa sediments exactly match the timing of three known episodes of prolonged regional drought within the past 250 years. Additionally, the principal trends of inferred rainfall variability over the past two millennia are consistent with the hydroclimatic history of equatorial East Africa, as has been documented from other (but less well dated) regional lake records. We therefore propose that variation in GDGT production originating from the episodic recurrence of strong soil-erosion events, when integrated over (multi-)decadal and longer timescales, generates a stable positive relationship between the sedimentary BIT index and monsoon rainfall at Lake Challa. Application of this paleoprecipitation proxy at other sites requires ascertaining the local processes which affect the productivity of crenarchaeol by Thaumarchaeota and brGDGTs.

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Abdulhamid, Mohanad, and Mwaniki Muchai. "Performance of Multiple Rank Modulation Based on SM-MIMO." Land Forces Academy Review 24, no. 1 (March 1, 2019): 61–67. http://dx.doi.org/10.2478/raft-2019-0007.

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Abstract A multiple rank modulation (MRM) scheme is proposed that provides better error performance, enhances the data rate and reduces the system demodulation complexity. Multiple input multiple output (MIMO) scheme is a technique that uses several antennas at the transmitter and receiver to minimize error and optimize data speed. MRM is a novel technique that borrows from spatial modulation-MIMO (SM-MIMO) scheme. The basic idea of this scheme involves the transmitter receiving a group of bits and subdividing them into two blocks; rank index block and signal modulation block. The rank index bit block is used to select the rank to be activated and the rank selected contains at least one active transmit antenna (TA). The signal modulation bit block is encoded in a given modulation scheme for transmission. It is then transmitted through the activated rank that contains at least one active TA. The transmitted encoded signal modulation bit block is received through the receive antenna and a receiver. The receiver estimates a rank index and the transmitted symbol from the signal received. The signal modulation bit block is finally decoded. This paper addresses the performance of MRM scheme based on error performance to run cellular fifth generation (5G). We perform and present simulation results of MIMO systems employing MRM scheme to generate bit error rate (BER) of this system.

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Le-Tran, Manh, and Sunghwan Kim. "Deep Learning-Assisted Index Estimator for Generalized LED Index Modulation OFDM in Visible Light Communication." Photonics 8, no. 5 (May 19, 2021): 168. http://dx.doi.org/10.3390/photonics8050168.

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In this letter, we present the first attempt of active light-emitting diode (LED) indexes estimating for the generalized LED index modulation optical orthogonal frequency-division multiplexing (GLIM-OFDM) in visible light communication (VLC) system by using deep learning (DL). Instead of directly estimating the transmitted binary bit sequence with DL, the active LEDs at the transmitter are estimated to maintain acceptable complexity and improve the performance gain compared with those of previously proposed receivers. Particularly, a novel DL-based estimator termed index estimator-based deep neural network (IE-DNN) is proposed, which can employ three different DNN structures with fully connected layers (FCL) or convolution layers (CL) to recover the indexes of active LEDs in a GLIM-OFDM system. By using the received signal dataset generated in simulations, the IE-DNN is first trained offline to minimize the index error rate (IER); subsequently, the trained model is deployed for the active LED index estimation and signal demodulation of the GLIM-OFDM system. The simulation results show that the IE-DNN significantly improves the IER and bit error rate (BER) compared with those of conventional detectors with acceptable run time.

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Kochkodan, Ya M., and A. I. Vasko. "The Study of the Interaction of Different Arrangements of the Bottom-Hole Assembly with the Bottomhole and the Borehole Wall." Prospecting and Development of Oil and Gas Fields, no. 3(72) (September 30, 2019): 58–68. http://dx.doi.org/10.31471/1993-9973-2019-3(72)-58-68.

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The article presents the main factors affecting the buckling when drilling vertical wells. The authors study analytically the effect of the weight on the bit and the force of the interaction of a drill string with a borehole wall using a uniform-sized arrangement of the bottom-hole assembly and the borehole wall which is located in a deviated wellbore when drilling in isotropic rocks in case the drilling direction coincides with the direction of the force acting on the bit. Differential equations of the elastic axis of the drill string are worked out. The solutions of these equations have given nondimensional dependences between the technological parameters. The authors have obtained the graphical dependences of the distance from the bit to the “drill string - borehole wall” contact point and the normal reaction of the bottom to the bit and the “drill string - borehole wall” clearance. The dependence for identifying the drilling anisotropy index in oblique beds is obtained. An interrelation between the anisotropy drilling index, the zenith angle, the bedding angle, the bottom-hole assembly, the borehole dimensions and the axial weight on the bit has been established. The authors have studied analytically the effect of the weight on the bit and the force of the “drill string - borehole wall” interaction, when installing the centralizer to the bottom-hole assembly. The differential equations of the elastic axis of the drill string with the centralizer in the bottom-hole assembly are obtained. It is established that with the increase in the axial weight on the bit and the “drill collars - borehole wall” clearance, the distance from the bit to the contact point of the borehole wall decreases; whereas with the increase of the deviation angle and the clearance, the pressure force of the column on the walls increases. It has also been established that the anisotropy drilling index reduces the distance from the bit to the point contact both in a slick BHA and in the bottom hole assembly with the centralizer. The presence of a centralizer in the bottom hole assembly increases the distance from the bit to the contact point between the string and the borehole wall, makes it possible to increase the weight on the bit without the risk of increasing a deviation angle.

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Dumitrescu, Sorina, and Yinghan Wan. "Bit-Error Resilient Index Assignment for Multiple Description Scalar Quantizers." IEEE Transactions on Information Theory 61, no. 5 (May 2015): 2748–63. http://dx.doi.org/10.1109/tit.2015.2413780.

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Liu, Ye, and Justin P. Coon. "Mitigating Bit-Synchronization Errors in Huffman-Coding-Aided Index Modulation." IEEE Communications Letters 23, no. 3 (March 2019): 426–29. http://dx.doi.org/10.1109/lcomm.2018.2889757.

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Xie, Hongtao, Zhendong Mao, Yongdong Zhang, Han Deng, Chenggang Yan, and Zhineng Chen. "Double-Bit Quantization and Index Hashing for Nearest Neighbor Search." IEEE Transactions on Multimedia 21, no. 5 (May 2019): 1248–60. http://dx.doi.org/10.1109/tmm.2018.2872898.

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Seo, Young-Ho, Hyun-Jun Choi, Ji-Sang Yoo, and Dong-Wook Kim. "Adaptive Watermarking Scheme Using Biased Shift of Quantization Index." Journal of Electrical and Computer Engineering 2010 (2010): 1–6. http://dx.doi.org/10.1155/2010/348321.

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We propose a watermark embedding and extracting method for blind watermarking. It uses the characteristics of a scalar quantizer to comply with the recommendation in JPEG, MPEG series, or JPEG2000. Our method performs embedding of a watermark bit by shifting the corresponding frequency transform coefficient (the watermark position) to a quantization index according to the value of the watermark bit, which prevents from losing the watermark information during the data compression process. The watermark can be embedded simultaneously to the quantization process without an additional process for watermarking, which means it can be performed at the same speed to the compression process. In the embedding process, a Linear Feedback Shift Register (LFSR) is used to hide the watermark informations and the watermark positions. The experimental results showed that the proposed method satisfies enough robustness and imperceptibility that are the major requirements for watermarking.

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Xu, Jiangtao, Xiyang Zhao, Liqiang Han, Kaiming Nie, Liang Xu, and Jianguo Ma. "Effect of the Transition Points Mismatch on Quanta Image Sensors." Sensors 18, no. 12 (December 10, 2018): 4357. http://dx.doi.org/10.3390/s18124357.

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Mathematical models and imaging models that show the relationship between the transition points mismatch of analog-to-digital converters (ADCs) and the bit error rate (BER) in single-bit and multi-bit quanta image sensors (QISs) are established. The mathematical models suggest that when the root-mean-square (r.m.s.) of the read noise in jots is 0.15e−, the standard deviation of the transition points should be less than 0.15e− to ensure that the BER is lower than 1% in the single-bit QIS, and 0.21e− to ensure that the BER is lower than 5% in the multi-bit QIS. Based on the mathematical models, the imaging models prove that the fixed-pattern noise (FPN) increases with a stronger transition point mismatch. The imaging models also compare the imaging quality in the case of different spatial oversampling factors and bit depths. The grayscale similarity index (GSI) is 3.31 LSB and 1.74 LSB when the spatial oversampling factors are 256 and 4096, respectively, in the single-bit QIS. The GSI is 1.93 LSB and 1.13 LSB when the bit depth is 3 and 4, respectively, in the multi-bit QIS. It indicates that a higher bit depth and a larger spatial oversampling factor could reduce the effect of the transition points mismatch of1-bit or n-bit ADCs.

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Wang, Fu Hua, Rui He Wang, and Xue Chao Tan. "How to Improve Rate of Penetration for Oil and Gas Wells." Advanced Materials Research 524-527 (May 2012): 1439–49. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.1439.

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Improved optimization of drilling bit selection and the compatibility between drilling bit and formation constraint the ROP and cost of deep well drilling to some extent. This combined with lab comprehensive lab drilling simulations and mechanisms of rock penetration can hold promise for improving drilling efficiency in deep wells. This paper reviews the mechanical characteristic parameters of rock engineering and demonstrates the obstacle of rock penetration in deep wells. Based on the general predictable formula of ROP, the relationship between drilling sensitive index and formation drillability is analyzed and the optimization and optimal match of drilling technology parameters are described. Technology Benefit Index (TBI) is proposed to evaluate the technical performance of drilling bit, advices and warnings from lab experiment and field experience on selecting and using bit are put forward. Statistical analysis of Well A based on TBI is made, the analysis of ROP improvement potential and overall program (including Bottom Hole Assembly, drilling parameters and type of drilling bit) of ROP improvement for Well B are worked out. Suggestions of drilling bit using based on mechanisms of rock penetration are proposed. Guided by the theory on improving ROP field tests of improving drilling rate are conducted to examine the field performance. By comparison, the tested sections yield high performance of ROP improvement. The designed program enhancing ROP for experiment section proves to be operable and shows great promise in further improvement and application.

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Journal, Baghdad Science. "Biodiversity of Rotifera and Cladocera in the upper region of Euphrates River- Iraq." Baghdad Science Journal 4, no. 2 (June 3, 2007): 221–32. http://dx.doi.org/10.21123/bsj.4.2.221-232.

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Five representative sampling stations were selected in upper region of Euphrates river. Bimonthly sampling were collected from December 2000 to December 2001. Rotifera showed high density in December 2000 while high density of cladocera which recorded in October .The results of relative abundance index showed that rotifera: Polyarthera dolichoptera , Keratella cochlearis , K. valga, Cephalodella auriculata and cladocera: Bosmina longirostris , B.coregoni ,Chydorus spharicus, were more abundant in study stations. The results of constancy index showed 4 taxa belonged to rotifera and 2 taxa belonged to cladocera which were considered constant in the Euphrates river, where the other species varied between accessory and accidental species in study stations. The index values of Species richness of rotifera varied between 0.41 – 2.8 and cladocera varied between 0.5 - 1.95. The Shanon-Weiner index of rotifera varied between 0.54-1.72 bit/ind., while the Shanon index of cladocera varied between 0.5-1.6 bit/ind. The uniformity index of rotifera varied between 0.41 – 0.99 but the uniformity index of cladocera varied between 0.61- 0.98 .

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Zhang, Yu Long, Guo Chu Shou, Yi Hong Hu, and Zhi Gang Guo. "Low Complexity GF(2^m) Multiplier Based on Iterative Karatsuba Algorithm." Advanced Materials Research 546-547 (July 2012): 1409–14. http://dx.doi.org/10.4028/www.scientific.net/amr.546-547.1409.

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The complexity is one important index for Galois Field multiplier. This paper presents one low complexity GF(2m) multiplier based on iterative Karatsuba algorithm. The multiplication is replaced iteratively by three ones of half-length operands which are performed in parallel. The operands are divided into different width such as 64-bit, 32-bit, 16-bit and so on. For the 2m*2mmultiplier, we take 128 bit-widthGF(2128) multipliers as an example. We implement them on FPGA and count the number of the used LUTs and the used registers. Through analyzing the statistic, we find that, when the width of the two multiplication operands is divided to 8 bit, the multiplier consumes the least resources. Compared with the FPGA implementation of the other previous multiplier, this optimum multiplier can save 50% resources in LUTs and the registers.

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Kwon, Young Jik, and Ching-An Peng. "Transduction rate constant as more reliable index quantifying efficiency of retroviral gene delivery." Biotechnology and Bioengineering 77, no. 6 (January 22, 2002): 668–67. http://dx.doi.org/10.1002/bit.10214.

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Zhu, Chun Sheng, Qi Zhang, Fan Tun Su, and Hong Liang Ran. "Research on the Multi-Objective Optimization Model of System-Level BIT Testability Index Determination." Applied Mechanics and Materials 121-126 (October 2011): 2223–27. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.2223.

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By weighing reliability, maintainability, availability and life-cycle cost of equipment which are influenced by testability，the testability indexes of system level BIT are determined on the basis of maximum system reliability & maintainability and minimum the life-circle cost. The influence mathematical models of system reliability, maintainability, availability and life-circle cost are established. According to these mathematical models, the multi-objective optimization model of system-level BIT testability indexes is established. The multi-objective optimization model is solved using Non-dominated Sorting Genetic Algorithm II, and the validity of the multi-objective optimization model is proved through an example.

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Dumitrescu, Sorina, Yifang Chen, and Jun Chen. "Index Mapping for Bit-Error Resilient Multiple Description Lattice Vector Quantizer." IEEE Transactions on Communications 66, no. 8 (August 2018): 3638–52. http://dx.doi.org/10.1109/tcomm.2018.2816070.

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Miao, Jianhui, Zhiyang Li, Zeyan Zhou, Chuanfu Yang, Zhaobin Liu, and Weijiang Liu. "Nearest Neighbor Search Based on Bit String Partition and Multiple Index." Journal of Computer-Aided Design & Computer Graphics 31, no. 5 (2019): 771. http://dx.doi.org/10.3724/sp.j.1089.2019.17341.

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Nie, Zhao Gang, Xin Zhong Li, Yu Ping Tai, Ki Soo Lim, and Myeongkyu Lee. "Three-Dimensional Optical Bit Memory in Sm(DBM)₃Phen-Doped and Un-Doped Poly(methyl methacrylate)." Advanced Materials Research 284-286 (July 2011): 2251–54. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.2251.

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The feasibility of three-dimensional optical bit memory is demonstrated by using the change of fluorescence and refractive index in Sm(DBM)3Phen-doped and un-doped Poly(methyl methacrylate). After a femtosecond pulsed laser irradiation, a refractive-index bit and a fluorescent bit can be formed at the same position inside the bulk sample. Multilayer patterns recorded by tightly focusing the pulsed laser beam were read out by a reflection-type fluorescent confocal microscope, which can detect the reflection signal and also the fluorescent signal of the stored bits. The signal-to-noise ratio via the two retrieval modes was compared as a function of recording depth. The stored bits were retrieved with a high signal-to-noise ratio in the absence of any crosstalk and the detection of the fluorescent signal enables retrieval of the stored bits with a higher S/N ratio.

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Lattaud, Julie, Denise Dorhout, Hartmut Schulz, Isla S. Castañeda, Enno Schefuß, Jaap S. Sinninghe Damsté, and Stefan Schouten. "The C32 alkane-1,15-diol as a proxy of late Quaternary riverine input in coastal margins." Climate of the Past 13, no. 8 (August 22, 2017): 1049–61. http://dx.doi.org/10.5194/cp-13-1049-2017.

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Abstract. The study of past sedimentary records from coastal margins allows us to reconstruct variations in terrestrial input into the marine realm and to gain insight into continental climatic variability. There are numerous organic proxies for tracing terrestrial input into marine environments but none that strictly reflect the input of river-produced organic matter. Here, we test the fractional abundance of the C32 alkane 1,15-diol relative to all 1,13- and 1,15-long-chain diols (FC32 1, 15) as a tracer of input of river-produced organic matter in the marine realm in surface and Quaternary (0–45 ka) sediments on the shelf off the Zambezi and nearby smaller rivers in the Mozambique Channel (western Indian Ocean). A Quaternary (0–22 ka) sediment record off the Nile River mouth in the eastern Mediterranean was also studied for long-chain diols. For the Mozambique Channel, surface sediments of sites most proximal to Mozambique rivers showed the highest F1, 15 − C32 (up to 10 %). The sedimentary record shows high (15–35 %) pre-Holocene F1, 15 − C32 and low (< 10 %) Holocene F1, 15 − C32 values, with a major decrease between 18 and 12 ka. F1, 15 − C32 is significantly correlated (r2 = 0.83, p < 0.001) with the branched and isoprenoid tetraether (BIT) index, a proxy for the input of soil and river-produced organic matter in the marine environment, which declines from 0.25 to 0.60 for the pre-Holocene to < 0.10 for the Holocene. This decrease in both FC32 1, 15 and the BIT is interpreted to be mainly due to rising sea level, which caused the Zambezi River mouth to become more distal to our study site, thereby decreasing riverine input at the core location. Some small discrepancies are observed between the records of the BIT index and FC32 1, 15 for Heinrich Event 1 (H1) and the Younger Dryas (YD), which may be explained by a change in soil sources in the catchment area rather than a change in river influx. Like for the Mozambique Channel, a significant correlation between FC32 1, 15 and the BIT index (r2 = 0.38, p < 0.001) is observed for the eastern Mediterranean Nile record. Here also, the BIT index and FC32 1, 15 are lower in the Holocene than in the pre-Holocene, which is likely due to the sea level rise. In general, the differences between the BIT index and FC32 1, 15 eastern Mediterranean Nile records can be explained by the fact that the BIT index is not only affected by riverine runoff but also by vegetation cover with increasing cover leading to lower soil erosion. Our results confirm that FC32 1, 15 is a complementary proxy for tracing riverine input of organic matter into marine shelf settings, and, in comparison with other proxies, it seems not to be affected by soil and vegetation changes in the catchment area.

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Guangsheng, Li, Ou Bo, and Wang Jianyuan. "Digital NBC Protection System BIT Optimization Design." MATEC Web of Conferences 288 (2019): 01010. http://dx.doi.org/10.1051/matecconf/201928801010.

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BIT technology is an important means of system and equipment fault detection, location and isolation. This paper takes the digital NBC protection system as the research object, and carries out research on the optimization design based on BIT technology. Based on the structural division of the digital NBC protection systems and the analysis of typical failure modes, combined with the weighted cost index function and the selection method of the improved special hierarchically optimized optimal test set, the calculation and comparison of the indices of the actual digitalized NBC protection systems was conducted. Determine the optimal test set, and finally design the BIT circuit for the selected optimal test set.

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B S, Lokesh, and Dr Manjunatha M B. "Thermal Image Encryption Based on Region of Interest (ROI) and Chaotic map." International Journal of Engineering & Technology 7, no. 3 (August 24, 2018): 1944. http://dx.doi.org/10.14419/ijet.v7i3.15878.

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Most of the thermal image information concentrated on a particular region and 50% of image information stored in Most Significant Bit (MSB) plane. Based on these two strategy, proposed an thermal image encryption based on region of interest (ROI) and chaotic map. Firstly extract the MSB bit plane of thermal input image. This MSB bit plane undergo ROI calculation method. This method involves the partition of MSB bit plane into several 16*16 blocks. Apply the thresholding function to each block to separate the ROI blocks. Then selected part from input thermal image undergo XOR operation between random image generated from chaotic map. For lossless decryption at the receiver side, embedded the index of ROI blocks using LSB embedding algorithm. Simulation results shows the proposed algorithm achieves good security and more efficiency.

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Sahu, Aditya Kumar, Gandharba Swain, and E. Suresh Babu. "Digital Image Steganography Using Bit Flipping." Cybernetics and Information Technologies 18, no. 1 (March 1, 2018): 69–80. http://dx.doi.org/10.2478/cait-2018-0006.

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Abstract This article proposes bit flipping method to conceal secret data in the original image. Here a block consists of 2 pixels and thereby flipping one or two LSBs of the pixels to hide secret information in it. It exists in two variants. Variant-1 and Variant-2 both use 7th and 8th bit of a pixel to conceal the secret data. Variant-1 hides 3 bits per a pair of pixels and the Variant-2 hides 4 bits per a pair of pixels. Our proposed method notably raises the capacity as well as bits per pixel that can be hidden in the image compared to existing bit flipping method. The image steganographic parameters such as, Peak Signal to Noise Ratio (PSNR), hiding capacity, and the Quality Index (Q.I) of the proposed techniques has been compared with the results of the existing bit flipping technique and some of the state of art article.

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Maiga, Ali, Jean-Yves Baudais, and Jean-François Hélard. "Bit Rate Optimization with MMSE Detector for Multicast LP-OFDM Systems." Journal of Electrical and Computer Engineering 2012 (2012): 1–12. http://dx.doi.org/10.1155/2012/232797.

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We propose a new resource allocation algorithm with minimum mean square error (MMSE) detector for multicast linear precoded orthogonal frequency division multiplexing (LP-OFDM) systems. To increase the total multicast bit rate, this algorithm jointly uses the LP-OFDM modulation technique and an adaptation of the OFDM-based multicast approaches to exploit the transmission link diversities of users. The LP technique applied to multicast OFDM systems with zero forcing (ZF) detector has already proved its ability to increase the unirate multicast system bit rate in a power line communication (PLC) context. The new MMSE detector and the new related bit-loading algorithm are developed to enhance the ZF detector results. To improve both the bit rate and the fairness among multicast users, the utilization of the LP component in multirate multicast systems is then investigated. Simulations are run over indoor PLC channels, and it is shown that the proposed LP-based methods outperform the OFDM-based methods in terms of total bit rate and fairness index for both unirate and multirate multicast systems. Additionally, it is shown that the proposed bit-loading algorithm with MMSE detector outperforms the ZF detector and the OFDM-based receiver in terms of total multicast bit rate and fairness among users.

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CH, Subrahmanyam, Venkata Rao D, and Usha Rani N. "Low bit Rate Video Quality Analysis Using NRDPF-VQA Algorithm." International Journal of Electrical and Computer Engineering (IJECE) 5, no. 1 (February 1, 2015): 71. http://dx.doi.org/10.11591/ijece.v5i1.pp71-77.

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In this work, we propose NRDPF-VQA (No Reference Distortion Patch Features Video Quality Assessment) model aims to use to measure the video quality assessment for H.264/AVC (Advanced Video Coding). The proposed method takes advantage of the contrast changes in the video quality by luminance changes. The proposed quality metric was tested by using LIVE video database. The experimental results show that the new index performance compared with the other NR-VQA models that require training on LIVE video databases, CSIQ video database, and VQEG HDTV video database. The values are compared with human score index analysis of DMOS.

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Kahkashan, Sanober, Jianfang Chen, Xinhong Wang, Peter D. Clift, Bassem Jalali, Asif Inam, Monawwar Saleem, et al. "Holocene organic geochemical record from the Western Indus continental shelf (northern Arabian Sea)." Holocene 30, no. 6 (March 16, 2020): 810–19. http://dx.doi.org/10.1177/0959683620902213.

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Primary production on the Western Indus continental shelf has been linked to the large quantities of nutrients delivered to the shelf by the Indus River. Multiple geochemical tracers and biomarker records, including stable isotopes (δ13C and δ15N), total organic carbon (TOC), total nitrogen (TN), molar carbon/nitrogen (C/N) ratio, the branched and isoprenoid tetraether (BIT) index, and glycerol dialkyl glycerol tetraether (GDGT), have been analyzed from the Indus-23AP sediment core recovered from the northern Arabian Sea. Our records show evidence of a mixture of marine and terrestrially derived organic matter (OM) during the last 14,000 years, as indicated by the C/N ratio, δ13C, δ15N, and the BIT index. The three sterol biomarkers (brassicasterol, dinosterol, and cholesterol) show concurrent enrichments during the last 3 millennia reflecting increased phytoplankton abundance because of increased Indus river discharge of nutrients during the summer monsoon. GDGT crenarchaeol enrichment is related to the BIT index. The TEX86-derived sea surface temperature (SST) record is shifted toward the summer season because Crenarchaeota are more abundant and active during periods of high primary production. SSTs indicate a long-term warming trend during the Holocene related to increasing winter insolation in the low latitudes northern Hemisphere.

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Qiu, Pengqi, Xuehui Li, Jianguo Ning, Jun Wang, and Shang Yang. "Study on Thermal Energy Conversion Theory in Drilling Process of Coal and Rock Mass with Different Stresses." Energies 12, no. 22 (November 10, 2019): 4282. http://dx.doi.org/10.3390/en12224282.

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In view of the problem that the evolutionary mechanism of bit temperature during the drilling process is still unclear and the influencing factors are complex, this paper analyzes the causes of heat generation and the factors of heat production when the drill bit interacts with the coal and rock mass. Considering the stress field distribution of coal and rock mass and the dynamic characteristics of drilling, a three-dimensional mechanical structure model of bit drilling is established in this paper, based on the energy conservation theory and introducing the friction heat micro-distribution mechanism. The corresponding relationship between coal stress and the bit temperature variation rate is obtained in this paper. Therefore, the temperature rise condition model and the coal stress identification model can be verified, combined with the existing experimental data. The result shows that the temperature of bit drilling is affected by factors such as bit geometry and drilling parameters, as well as the strength and stress state of the coal and rock. Without considering other factors, the rate of increase in bit temperature is proportional to the stress of the coal and rock mass. Based on the research results, the temperature rate of the drill bit can be used as an index to identify the stress areas of coal and rock mass. Research results provide a theoretical basis for the identification of high-stress risk areas in coal mines.

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Kim, Jung-Hyun, Xavier Crosta, Elisabeth Michel, Stefan Schouten, Josette Duprat, and Jaap S. Sinninghe Damsté. "Impact of lateral transport on organic proxies in the Southern Ocean." Quaternary Research 71, no. 2 (March 2009): 246–50. http://dx.doi.org/10.1016/j.yqres.2008.10.005.

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AbstractLateral transport of fine-grained organic carbon particles can complicate the interpretation of paleoclimate records based on organic proxies. Here we investigated the effect of lateral transport on newly developed temperature and soil organic matter proxies, TEX86 and BIT index, respectively, in core MD88–769 recovered from the South East Indian Ridge. Our results show that TEX86 and BIT records in comparison to diatom and foraminifera records were representative for more local climate changes while alkenones and n-alkanes originated from distant areas by oceanic and atmospheric transport, respectively. This suggests that TEX86 and BIT paleoclimate records are primarily influenced by local conditions and less subjected to long-distance lateral transport than other organic proxies in the Southern Ocean.

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Abdullahi, Mahmoud, Aijun Cao, Adnan Zafar, Pei Xiao, and Ibrahim A. Hemadeh. "A Generalized Bit Error Rate Evaluation for Index Modulation Based OFDM System." IEEE Access 8 (2020): 70082–94. http://dx.doi.org/10.1109/access.2020.2972113.

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Li, Song-bin, Huai-zhou Tao, and Yong-feng Huang. "Detection of quantization index modulation steganography in G.723.1 bit stream based on quantization index sequence analysis." Journal of Zhejiang University SCIENCE C 13, no. 8 (August 2012): 624–34. http://dx.doi.org/10.1631/jzus.c1100374.

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Kuta, Stanisław, Wojciech Kołodziejski, and Jacek Jasielski. "Hybrid Linearized Class-BD Double Sided (LBDD) Digital Pulse Width Modulator (DPWM) for Class-BD Audio Amplifiers." Science, Technology and Innovation 1, no. 1 (December 27, 2017): 1–10. http://dx.doi.org/10.5604/01.3001.0010.7555.

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The paper presents an original architecture and implementation of 9-bit LBDD hybrid DPWM circuit for Class-BD digital audio amplifier. The input PCM signals are directly transformed into 24-bit LBDD DPWM signals and then are requanized to the 9-bit digital outputs using noise-shaping process to support high fidelity with practical values of time resolution, and finally are converted by the DTCs into the two physical trains of 1-bit PWM signals. The architecture of the proposed Class-BD hybrid DPWM circuit is composed of two Class-AD ones. The hybrid quantizer converts 6 MSB bits using counter method, based on the STM32F407xx microcontroller, while the remaining 3 LSB bits - using a method based on the Programmable Tapped Delay Line (PTDL). All necessary time waveforms are generated on the base of the internal microcontroller oscillator 168 MHz. The proposed 9-bit Class-DB DPWM circuit allows to attain SNR of 110 dB and THD about 0,2% within the audio baseband, at switching frequency of 328.1 kHz, clock frequency of 42 MHz and modulation index M = 0.95. Basic verification of algorithm and circuit operation as well as simulation and preliminary experimental results have been performed.

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HOSAIN, MD SHAZZAD, and MUHAMMAD ABDUL HAKIM NEWTON. "MULTI-KEY INDEX FOR DISTRIBUTED DATABASE SYSTEM." International Journal of Software Engineering and Knowledge Engineering 15, no. 02 (April 2005): 433–38. http://dx.doi.org/10.1142/s0218194005002075.

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In this paper we present a multi-key index model that enables us to search a record with more than one attribute values in distributed database systems. Indices provide fast and efficient access of data and so become a major aspect in centralized database systems. Most of the centralized database systems use B + tree or other types of index structures such as bit vector, graph structure, grid file etc. But in distributed database systems no index model is found in the literature. Therefore efficient access is a major problem in distributed databases. Our proposed index model avoids the query-flooding problem of existing system and thus optimizes network bandwidth.

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Gea, Teresa, Raquel Barrena, Adriana Artola, and Antoni Sánchez. "Monitoring the biological activity of the composting process: Oxygen uptake rate (OUR), respirometric index (RI), and respiratory quotient (RQ)." Biotechnology and Bioengineering 88, no. 4 (September 30, 2004): 520–27. http://dx.doi.org/10.1002/bit.20281.

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LEE, Hye Yeong, and Soo Young Shin. "A novel index modulation scheme with impedance matching." Indonesian Journal of Electrical Engineering and Computer Science 14, no. 3 (June 1, 2019): 1203. http://dx.doi.org/10.11591/ijeecs.v14.i3.pp1203-1209.

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Index modulation conveys more data given to indices of status of communication transmission item such as antenna and subcarrier. In this proposed system, we gave the index to the conditions of impedance matching or not. In the transmitter, antenna chooses one impedance according to the mapping table as active impedance. The receiver detects impedance index comparing of impedance between received signal and receivers. The proposed system improves not only transmitted information data by using impedance index but also spectral efficiency. In the simulation, Spectral Efficiency (SE) and Bit Error Rate (BER) were analyzed and compared to conventional modulation scheme.

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Wu, Ning, Yi Yang, Lian Li, Zhongliang Yang, Poli Shang, Weibo Ma, and Zhenru Liu. "Coverless Text Hiding Method Based on Improved Evaluation Index and One-Bit Embedding." Computer Modeling in Engineering & Sciences 124, no. 3 (2020): 1035–48. http://dx.doi.org/10.32604/cmes.2020.010450.

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Jain, Monika, Anirudh Agarwal, Divyang Rawal, and Ranjan Gangopadhyay. "Adaptive bit and power allocation for dual mode index modulation based OFDM system." Physical Communication 40 (June 2020): 101093. http://dx.doi.org/10.1016/j.phycom.2020.101093.

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Fujine, T., T. Kanda, Y. Yoshida, M. Sugino, M. Teragawa, Y. Yamamoto, and N. Ohta. "Bit Depth Needed for High Image Quality TV-Evaluation Using Color Distribution Index." Journal of Display Technology 4, no. 3 (September 2008): 340–47. http://dx.doi.org/10.1109/jdt.2008.926488.

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Lundin, H., M. Skoglund, and P. Handel. "Optimal index-bit allocation for dynamic post-correction of analog-to-digital converters." IEEE Transactions on Signal Processing 53, no. 2 (February 2005): 660–71. http://dx.doi.org/10.1109/tsp.2004.840817.

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Orchard, M. "Fast bit-reversal algorithms based on index representations in GF (2/sup b/)." IEEE Transactions on Signal Processing 40, no. 4 (April 1992): 1004–8. http://dx.doi.org/10.1109/78.127979.

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Tian, Hui, Jin Liu, and Songbin Li. "Improving security of quantization-index-modulation steganography in low bit-rate speech streams." Multimedia Systems 20, no. 2 (February 2, 2013): 143–54. http://dx.doi.org/10.1007/s00530-013-0302-8.

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Qiao, Na, Bin Zhang, Pingping Pan, and Youquan Dan. "Scintillation index and bit error rate of hollow Gaussian beams in atmospheric turbulence." Journal of Modern Optics 58, no. 11 (June 20, 2011): 939–44. http://dx.doi.org/10.1080/09500340.2011.582961.

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Ukrainetz, Nicholas K., and Gregory A. O’Neill. "An analysis of sensitivities contributing measurement error to Resistograph values." Canadian Journal of Forest Research 40, no. 4 (April 2010): 806–11. http://dx.doi.org/10.1139/x10-019.

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As a hand-held, portable tool capable of assessing wood density of standing trees quickly and inexpensively, the Resistograph holds considerable potential application for evaluating forest genetics field tests. However, phenotypic correlations between Resistograph density index values and values from conventional wood density assessment techniques are weak. In an effort to investigate the extent to which environmental, operator, or instrument factors may affect density index values, we evaluated the sensitivity of Resistograph measurements to seven experimental factors. Drill bit flexion (a measure of operator steadiness), moisture content of wood, and air temperature significantly affected Resistograph density index values, while the influence of knots is minimized at a vertical distance of 3 cm. Battery type, sharpness of the drill bit (at least up to 350 uses), and battery charge (at least up to 310 uses with a 12 V motorcycle battery) had no significant effect on density index. By ensuring that the operator remains steady while drilling, sampling only live trees, only when air temperatures are above freezing, and by drilling at least 3 cm vertical distance from knots, measurement error should be minimized. Three measurements per tree are required to estimate density index to within 3 units 19 times out of 20.

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Journal articles on the topic 'BIT Index'

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