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The data mining and pervasive sensing technologies found in smart homes offer unprecedented opportunities for providing health monitoring and assistance to individuals experiencing difficulties living independently at home. In order to monitor the functional health of smart home residents, we need to design technologies that recognize and track activities that people normally perform as part of their daily routines. One question that frequently arises, however, is how many smart home sensors are needed and where should they be placed in order to accurately recognize activities? We employ data mining techniques to look at the problem of sensor selection for activity recognition in smart homes. We analyze the results based on six data sets collected in five distinct smart home environments.  相似文献   
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离心环辊磨是一种先进、新型的细磨设备,它以冲击、挤压、研磨的原理对物料进行粉碎.两层的粉碎腔结构,其工作面耦合严密,使物料粉碎充分,大大地提高了粉碎效率,因而该设备以其产量高、产品细、电耗省的优质凸现于目前国内同类的细磨设备,是干法生产非金属矿细粉(d97=5~10m)的理想设备.  相似文献   
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Baseline concentration levels of As, B, Ca, Cd, Cr, Cu, Co, Fe, Mg, Mn, Mo, Ni, P, Pb, Se, V, and Zn were determined for Porphyra columbina and Ulva sp. collected from three locations along San Jorge Gulf, in Patagonia Argentina. Elements were quantified by inductively coupled plasma-optical emission spectrometry, with the exception of lead and cadmium in some samples which were determined by electrothermal atomic absorption spectrometry. Three stations with different exposure degree to human activities, Bahía Solano, the mouth of Arroyo La Mata stream and Punta Maqueda, were selected as sampling points. The results showed a wide range of metal retention capacity between the two studied species. Regarding the levels of pollutants found in the researched sites, Punta Maqueda seemed to be less influenced by anthropogenic activities than the other two sites except for Cd. Taking into account their toxicities seasonal variations in Pb and Cd levels were studied in both algae in Punta Maqueda. Maximum concentrations of Cd (9.8 microg g(-1) dry wt.) were observed in P. columbina during winter, and maximum levels of Pb (0.82 microg g(-1) dry wt.) were detected in Ulva sp. during summer. Legislative and health safety aspects were evaluated for Cd and Pb.  相似文献   
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The objective of the study was to compare Holstein cows selected for large versus small body size for health care cost. All health treatments were recorded for cows from 1983 to 2005, and treatments were assigned to 1 of 11 categories of health disorders. Actual cost for veterinary treatments, health supplies, and drugs, as well as the value of labor required by animal attendants, was recorded. Data were for 1,035 lactations of 486 cows, of which 199 cows were from the large line and 287 cows were from the small line. Large-line cows had significantly greater total health cost than small-line cows during first lactation and tended to have greater total health cost for the first 3 lactations of cows. During first lactation, large-line cows had a total health cost of $62.41, and small-line cows had a total health cost of $41.41. Cows in the large line had significantly greater health cost for the individual categories of displaced abomasum and pneumonia than small-line cows during first lactation. Across the first 3 lactations, large-line cows had a total health cost per lactation of $54.15 and small-line cows had a total cost of $38.09. Cows in the large line had significantly greater health cost for the categories of locomotion and displaced abomasum across the first 3 lactations than small-line cows. Cost for displaced abomasum accounted for most the difference of health cost between the body size lines for both first lactation and for the first 3 lactations of cows.  相似文献   
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During smoked salmon processing, the dark meat along the lateral line is removed before packaging; this by-product currently has little economic value. In this study, the dark meat trim was incorporated into an extruded jerky. Three formulations were processed: 100% smoked trim, 75% : 25% smoked trim : fresh salmon fillet, and 50% : 50% smoked trim : fresh salmon blends (w/w basis). The base formulation contained salmon (approximately 83.5%), tapioca starch (8%), pregelatinized potato starch (3%), sucrose (4%), salt (1.5%), sodium nitrate (0.02%), and ascorbyl palmitate (0.02% of the lipid content). Blends were extruded in a laboratory-scale twin-screw extruder and then hot-smoked for 5 h. There were no significant differences among formulations in moisture, water activity, and pH. Protein was highest in the 50 : 50 blend jerky. Ash content was highest in the jerky made with 100% trim. Total lipids and salt were higher in the 100% trim jerky than in the 50 : 50 blend. Hot smoking did not adversely affect docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) content in lipids from 100% smoked trim jerky. Servings of salmon jerky made with 75% and 100% smoked trim provided at least 500 mg of EPA and DHA. The 50 : 50 formulation had the highest Intl. Commission on Illumination (CIE) L*, a*, and b* color values. Seventy consumers rated all sensory attributes as between "like slightly" and "like moderately." With some formulation and processing refinements, lateral line trim from smoked salmon processors has potential to be incorporated into acceptable, healthful snack products. PRACTICAL APPLICATION: Dark meat along the lateral line is typically discarded by smoked salmon processors. This omega-3 fatty acid rich by-product can be used to make a smoked salmon jerky that provides a convenient source of these healthful lipids for consumers.  相似文献   
8.
Biofiltration is a cost-effective technology for removing air contaminants from animal facilities. Kinetic analysis can be helpful in understanding and designing the process but has not been performed on full-scale filters treating complex mixtures. In this study, kinetics was investigated in a full-scale biological filter treating air pollutants from a pig facility. Due to the high air flow rates used in the filter, both a plug flow model and a model based on complete mixing were tested with respect to kinetic order and Michaelis-Menten kinetics. Application of these models only gave poor to moderate agreement with air filter removal data. Two alternative kinetic models (Stover-Kincannon model and Grau second-order model) adopted from wastewater biofiltration process analysis were introduced to analyze contaminant removal in the biological air filter. Data analysis demonstrated the applicability of these two models with a high degree of precision on contaminant removal in the biological air filter. Whereas the Stover-Kincannon model demonstrated that pollutant removal rates were related to the mass loading rates, the Grau second-order kinetic model indicated that the removal efficiencies were dependent on air loading rates. Therefore, the kinetic data can be used for comparing biofilter performances and for design purposes.  相似文献   
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Pure Holstein (HO) cows (n=416) were compared with Normande (NO) × HO (n=251), Montbéliarde (MO) × HO (n=503), and Scandinavian Red (SR) × HO (n=321) crossbred cows for survival, lifetime production, and profitability in 6 commercial herds in California. The SR crossbred cows were sired by both Swedish Red and Norwegian Red bulls. Cows calved from June 2002 to January 2009. For analysis of survival to subsequent calvings, lifetime production, and profitability, data were restricted to 3 of 6 herds because they had at least 20 cows in each of the breed groups. All cows had the opportunity to calve at least 4 times. Best prediction, which is used by USDA for national genetic evaluations in the United States, was used to determine lifetime production to 4 yr (1,461 d) in the herd after first calving from test-day observations. Production and survival were estimated after 4 yr to calculate lifetime profit. A profit function was defined to include revenues and expenses for milk, fat, protein, and other solids production; somatic cell count; reproduction; feed intake; calf value; salvage value; dead cow disposal; and fixed cost. The NO × HO (1.2%), MO × HO (2.0%), and SR × HO cows (1.6%) had significantly fewer deaths than did pure HO cows (5.3%) during the first 305 d of first lactation. All crossbred groups had significantly more cows that calved a second, third, and fourth time, and had mean survival that was 300 to 400 d longer than did pure HO cows. The NO × HO, MO × HO, and SR × HO cows had significantly higher lifetime fat plus protein production than did pure HO cows up to 1,461 d after first calving. For profitability (ignoring possible differences in health costs), NO × HO cows had 26% greater projected lifetime profit per cow, but 6.7% less profit per cow-day, than did pure HO cows. On the other hand, MO × HO and SR × HO cows had 50 to 44%, respectively, more projected lifetime profit per cow and 5.3 to 3.6%, respectively, more projected profit per cow-day than did pure HO cows.  相似文献   
10.
Intense physical activity results in a substantial volume of stress and hence a significant probability of immunosuppression in athletes, with milk proteins being, perhaps, the most recommended protein supplements. Consumption of a probiotic cheese can attenuate immune suppression induced by exhausting exercise in rats. A popular Brazilian fresh cheese (Minas Frescal cheese) containing Lactobacillus acidophilus LA14 and Bifidobacterium longum BL05 was fed for 2wk to adult Wistar rats, which then were brought to exhaustion on the treadmill. Two hours after exhaustion, the rats were killed and material was collected for the determination of serum uric acid, total and high-density lipoprotein cholesterol fraction, total protein, triacylglycerols, aspartate aminotransferase, alanine aminotransferase, creatine kinase, and blood cell (monocyte, lymphocyte, neutrophil, and leukocyte) counts. Exercise was efficient in reducing lymphocyte counts, irrespective of the type of ingested cheese, but the decrease in the group fed the probiotic cheese was 22% compared with 48% in the animals fed regular cheese. Monocyte counts were unaltered in the rats fed probiotic cheese compared with a significant decrease in the rats fed the regular cheese. Most importantly, ingestion of the probiotic cheese resulted in a >100% increase in serum high-density lipoprotein cholesterol and a 50% decrease in triacylglycerols. We conclude that probiotic Minas Frescal cheese may be a viable alternative to enhance the immune system and could be used to prevent infections, particularly those related to the physical overexertion of athletes.  相似文献   
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