1,101 research outputs found
A subsequence matching algorithm that supports normalization transform in time-series databases
In this paper, an algorithm is proposed for subsequence matching that supports normalization transform in time-series databases. Normalization transform enables finding sequences with similar fluctuation patterns even though they are not close to each other before the normalization transform. Simple application of existing subsequence matching algorithms to support normalization transform is not feasible since the algorithms do not have information for normalization transform of subsequences of arbitrary lengths. Application of the existing whole matching algorithm supporting normalization transform to the subsequence matching is feasible, but requires an index for every possible length of the query sequence causing serious overhead on both storage space and update time. The proposed algorithm generates indexes only for a small number of different lengths of query sequences. For subsequence matching it selects the most appropriate index among them. Better search performance can be obtained by using more indexes. In this paper, the approach is called index interpolation. It is formally proved that the proposed algorithm does not cause false dismissal. The search performance can be traded off with storage space by adjusting the number of indexes. For performance evaluation, a series of experiments is conducted using the indexes for only five different lengths out of lengths 256similar to512 of the query sequence. The results show that the proposed algorithm outperforms the sequential scan by up to 2.4 times on the average when the selectivity of the query is 10(-2) and up to 14.6 times when it is 10(-5). Since the proposed algorithm performs better with smaller selectivities, it is suitable for practical situations, where the queries with smaller selectivities are much more frequent
Efficient time-series subsequence matching using duality in constructing windows
In this paper, we propose a new subsequence matching method, Dual Match. Dual Match exploits duality in constructing windows and significantly improves performance. Dual Match divides data sequences into disjoint windows and the query sequence into sliding windows, and thus, is a dual approach of the one by Faloutsos et al. (Proceedings of the ACM SIGMOD International Conference on Management of Data, Seattle, Washington, 1994, pp. 419-429.) (FRM in short), which divides data sequences into sliding windows and the query sequence into disjoint windows. FRM causes a lot of false alarms (i.e., candidates that do not qualify) by storing minimum bounding rectangles rather than individual points representing windows to save storage space for the index. Dual Match solves this problem by directly storing points without incurring excessive storage overhead. Experimental results show that, in most cases, Dual Match provides large improvement both in false alarms and performance over FRM given the same amount of storage space. In particular, for low selectivities (less than 10(-4)), Dual Match significantly improves performance up to 430-fold. On the other hand, for high selectivities (more than 10(-2)), it shows a very minor degradation (less than 29%). For selectivities in between (10(-4)-10(-2)), Dual Match shows performance slightly better than that of FRM. Overall, these results indicate that our approach provides a new paradigm in subsequence matching that improves performance significantly in large database applications. (C) 2001 Elsevier Science Ltd. All rights reserved
Temporal Aggregation Using a Multidimensional Index
We present a new method for computing temporal aggregation that uses a multidimensional index. The novelty of our method lies in mapping the start time and end time of a temporal tuple to a data point in a two-dimensional space, which is stored in a two-dimensional index, and in calculating the temporal aggregates through a temporal join between the data in the index and the base intervals (defined as the intervals delimited by the start times or end times of the tuples). To enhance the performance, this method calculates the aggregates by incrementally modifying the aggregates from that of the previous base interval without re-reading all tuples for the current base interval. We have compared our method with the SB-tree, which is the state-of-the-art method for temporal aggregation. The results show that our method is an order of magnitude more efficient than the SB-tree method in an environment with frequent updates, while comparable in a read-only environment as the number of aggregates calculated in a query increases.</p
Behavior during transition differs for cows diagnosed with claw horn lesions in mid lactation
Claw horn lesions, including sole hemorrhages and sole ulcers, are a major cause of lameness in dairy cattle. These lesions often develop in the weeks around calving and become visible 8 to 12 wk later. The aim was to determine whether cows that are diagnosed with claw horn lesions several weeks after calving behave differently during the calving period when the lesions are thought to first develop. The claws of 26 multiparous Holstein dairy cows were scored for sole hemorrhage severity and presence of sole ulcers 2 wk before calving, 3 wk after calving, and every 4 wk thereafter until 15 wk after calving. Of the 26 cows, 13 cows had no or low lesion scores up to 15 wk and 13 cows had at least 1 new severe lesion or sole ulcer diagnosed between 7 and 15 wk after calving. Behavior (dry matter intake, feeding time and rate, number and size of meals, standing time, number and duration of standing bouts, location of standing, and displacements at the feed bunk) was recorded from 2 wk before calving to 3 wk after calving. Behavior during the 2 wk before calving, first 24h after calving, 1 wk after calving, and 2 to 3 wk after calving was compared between cows with and without lesions in mid lactation. Multivariate regression was used to determine the predictive value of each behavior and combination of behaviors on lesion diagnosis. Cows diagnosed with lesions in mid lactation spent more time standing than cows without lesions during the 2 wk before (832+/-29 vs. 711+/-29 min/d) and 24 h after (935+/-46 vs. 693+/-46 min/d) calving. These differences were driven by an increase in the time spent perching with front feet in the stall (241+/-22 vs. 147+/-22 min/d at 2 wk before calving) and an increase in standing bout duration (101+/-10 vs. 56+/-10 min/bout at 24 h after calving). Compared with cows without lesions, cows with lesions consumed feed at a faster rate (86+/-3 vs. 77+/-3 g/min) during the 2 wk before calving and consumed more feed (17.9+/-0.9 vs. 12.3+/-0.9 kg/d) during the 24 h after calving. The number of displacements at the feeder was not different between groups. These results indicate that a combination of feeding and standing behavior during the transition can serve as early indicators of claw horn lesions in mid lactation
On co-authorship for author disambiguation
Author name disambiguation deals with clustering the same-name authors into different individuals. To attack the problem, many studies have employed a variety of disambiguation features such as coauthors, titles of papers/publications, topics of articles, emails/affiliations, etc. Among these, co-authorship is the most easily accessible and influential, since inter-person acquaintances represented by co-authorship could discriminate the identities of authors more clearly than other features. This study attempts to explore the net effects of co-authorship on author clustering in bibliographic data. First, to handle the shortage of explicit coauthors listed in known citations, a web-assisted technique of acquiring implicit coauthors of the target author to be disambiguated is proposed. Then, a coauthor disambiguation hypothesis that the identity of an author can be determined by his/her coauthors is examined and confirmed through a variety of author disambiguation experiments. (C) 2008 Elsevier Ltd. All rights reserved.X1174sciescopu
Health and growth of veal calves provided a fatty acid supplement and a dry teat
Veal calves are at a high risk of disease early in life, which can lead to poor growth. Research is needed to determine interventions that can reduce disease and promote the growth of veal calves. The aim of this study was to determine the effects of fatty acid supplementation and the provision of a dry teat on the incidence of bovine respiratory disease (BRD), navel inflammation, and diarrhea, as well as calf growth. Upon arrival to a commercial veal facility (d 0), 240 Holstein bull calves from 2 cohorts were randomly assigned to 4 treatments using a 2 × 2 factorial arrangement (n = 60/treatment): (1) milk replacer (MR) without fatty acid supplementation and without access to a dry teat (control), (2) MR with fatty acid supplementation (NeoTec5g, Provimi, Brookville, OH) and without access to a dry teat (FAS), (3) MR without fatty acid supplementation and with access to a dry teat (TT), or (4) MR with fatty acid supplementation and with access to a dry teat (FAS+TT). Calves were housed in individual pens from 0 to 9 wk and then paired by treatment at wk 9. Milk replacer was fed twice daily using a step-up program. Fatty acid supplement was added to milk replacer at a feeding rate of 0.5 g/kg of body weight per head per day for the FAS and FAS+TT groups. Health exams were conducted twice weekly for 6 wk to diagnose BRD, navel inflammation, and diarrhea. Body weight, body condition score (BCS), and structural measurements were recorded at wk 0, 5, and 10. Average daily gain (ADG) was calculated for wk 1 to 5, wk 5 to 10, and wk 1 to 10. Health data were analyzed using logistic regression and are reported as relative risk. Body weight, BCS, and structural measurements were analyzed using repeated-measures ANOVA, and ADG was analyzed using a generalized linear model. There was no effect of FAS, TT, or their interaction on body weight or BCS. There was no effect of FAS on ADG wk 1 to 5, wk 5 to 10, or wk 1 to 10. There was a tendency for TT to decrease ADG from wk 1 to 5 but not from wk 5 to 10 or wk 1 to 10. There was a tendency for the interaction of FAS and TT to decrease ADG for wk 1 to 5 but not for wk 5 to 10 and wk 1 to 10. There was no effect of FAS, TT, or their interaction on the risk of BRD, diarrhea, or navel inflammation. We saw no effect of our interventions on calf health or growth. More research is needed to determine whether other factors, such as failure of passive transfer, poor ventilation, barren housing, and low milk allowance in the first few weeks after arrival, may have affected the efficacy of our interventions
Iterative methods for flexible manufacturing systems
This paper presents an Markovian model for flexible manufacturing systems (FMSs). The model captures two important features of a FMS: the reliability of machines and the capacity of the maintenance facility. A fast numerical algorithm based on preconditioned conjugate gradient (PCG) method is developed to solve the steady state probability distribution of the system. We prove the fast convergence rate of the PCG method. The performance analysis of the FMS can be evaluated by making use of the steady state probability distribution. © 2002 Elsevier Science Inc. All rights reserved.link_to_subscribed_fulltex
Fast density-based clustering through dataset partition using graphics processing units
Graphics processing units (GPUs) have been utilized to improve the processing speed of many conventional data mining algorithms. DBSCAN, a popular clustering algorithm that has been often used in practice, was extended to execute on a GPU. However, existing GPU-based DBSCAN extensions still have impediments in that the distances from all objects need to be repeatedly computed to find the neighbor objects and the objects and intermediate clustering results are stored in costly off-chip memory of the GPU. This paper proposes CudaSCAN, a novel algorithm that improves the efficiency of DBSCAN by making better use of the GPU. CudaSCAN consists of three phases: (1) partitioning the entire dataset into sub-regions of size of an integer multiple of the on-chip shared memory size in the GPU; (2) local clustering within sub-regions in parallel; and (3) merging the local clustering results. CudaSCAN allows an overlap between sub-regions to ensure independent, parallel local clustering in each sub-region, which in turn enables for objects and/or intermediate results to be stored in on-chip shared memory that has an access cost a few hundred times cheaper than that of off-chip global memory. The independence also enables for merging to be parallelized. This paper proves the correctness of CudaSCAN, and according to our extensive experiments, CudaSCAN outperforms CUDA-DClust, a previous GPU-based DBSCAN extension, by up to 163.6 times. (C) 2014 Elsevier Inc. All rights reserved.X1198sciescopu
Effects of supplemental vitamins E and C on the immune responses of calves
Two experiments were conducted to evaluate the effects of oral supplementation of vitamin C and vitamin E (alpha-tocopherol), alone and in combination, on immune responses of calves. In Experiment 1, 18 Holstein newborn female calves were supplemented with 0, 1, and 2 g/d of vitamin C from birth to 6 wk of age. Concentrations of ascorbic acid in blood plasma were significantly higher for supplemented calves than for control calves. No significant differences among treatments occurred in the concentrations of IgG1, IgG2, and titer to keyhole limpet hemocyanin. In Experiment 2, effects of oral supplementation of vitamins E and C on immune responses were studied using 18 Holstein female calves. Concentrations of alpha-tocopherol in blood plasma were significantly higher for supplemented than for control calves. The concentrations increased from birth to wk 1, and then very little change occurred from wk 1 to 6. Differences among treatments in the concentrations of IgG1, IgG2, IgM, and titer to keyhole limpet hemocyanin were not significant; however, concentrations of IgM in calves supplemented with vitamins E and C generally tended to be higher than those of control calves. Antibodies to keyhole limpet hemocyanin were higher at 6 wk than at 4 wk of age.LR: 20031114; PUBM: Print; JID: 2985126R; 0 (Antibodies); 0 (Antigens); 0 (Immunoglobulin G); 0 (Immunoglobulin M); 0 (keyhole-limpet hemocyanin); 1406-18-4 (Vitamin E); 50-81-7 (Ascorbic Acid); 9013-72-3 (Hemocyanin); ppublishSource type: Electronic(1
Randomized clinical trial to investigate the effectiveness of teflubenzuron for treating sea lice on Atlantic salmon
A double-blind, randomized control clinical trial was performed to investigate the effectiveness of teflubenzuron in controlling sea lice Lepeophtheirus salmonis on farmed Atlantic salmon Salmo salar. A total of 40 sea cages from 3 commercial cage sites in Atlantic Canada were used in this Good Clinical Practice (GCP) trial. The teflubenzuron was administered in the feed at a dosage of 10 mg kg(-1) biomass d(-1) for 7 d. Medicated and control cages were matched by site, cage size, and pre-treatment mean lice counts using cages as the unit of concern. Post-treatment lice counts and staging of developmental stages were performed at 1 and 2 wk after the end of treatment. Chalimus stages in medicated cages were significantly lower than in control cages at 1 wk (79% reduction in mean lice counts, p < 0.001), and at 2 wk (53% reduction, p < 0.001). Mobile (pre-adult and adult) stages were also significantly reduced in medicated cages at 1 wk (69% reduction, p < 0.01), and at 2 wk (40% reduction, p < 0.01) post-treatment, respectively. Teflubenzuron was proven effective for reducing lice burdens on salmon despite the low parasite levels experienced during the trial and the recruitment of lice from the untreated cages. The use of cage as the unit of concern was an important design component of this trial.LR: 20061115; PUBM: Print; JID: 8807037; 0 (Benzamides); 70288-86-7 (Ivermectin); 83121-18-0 (teflubenzuron); ppublishSource type: Electronic(1
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