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1.
Roger L. Kemp 《Cities》1985,2(3):252-255
Since the early 1970s, local governments in the USA have faced limited tax income combined with double-digit inflation. As a result, every local service from fire prevention to recreation has had to be closely scrutinized. Local administrators and politicians have evolved new and innovative retrenchment management policies to respond to both the demands of citizens and the fewer dollars available. A combination of denial of new programmes and public sector pay austerity, with public education and use of community organizations is providing ways to stretch limited funds. The reality in many communities across the USA is that local government and its services will not be growing in the future. 相似文献
2.
The author warns that it is not just personal computers and corporate IT systems that are at risk from impending date changes. He argues that the danger of embedded systems failing to cope should be just as great a cause for concern 相似文献
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Spatial information systems increasingly require incorporation of multimedia data types. Pictures, sounds, animated sequences, and unstructured text may form an integral part of geographically located entities in information systems. An example ecological application with extensive multimedia requirements illustrates how multimedia data can be integrated with spatial information systems in a generic, application-independent manner 相似文献
5.
Satya Ganti Zachary Gault Stanley Smith IV Jason A. Deibel Izaac Kemp Nicholas Schroeder Carl Druffner 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(11):1104-1116
Finite element method simulations of periodically corrugated metal terahertz wire waveguides have been conducted with concurrent analysis done on both the near-field confinement properties and the far-field emission properties at the end of the waveguides. This modeling was used to guide the choice of design parameters for the fabrication of waveguides with laser micromachining. The waveguides were characterized with a fiber-coupled terahertz time-domain spectroscopy and imaging system. The propagation properties as well as the frequency dependent diffraction at the end of the wire waveguides were examined and compared to straight, non-engineered metallic wire waveguides. 相似文献
6.
W. Steeneveld A.T.M. van Knegsel G.J. Remmelink B. Kemp J.C.M. Vernooij H. Hogeveen 《Journal of dairy science》2014
Shortening or omitting the dry period (DP) has been proposed as a management strategy to improve energy balance of dairy cows in early lactation. Both shortening and complete omission of the DP reduces milk production in the subsequent lactation compared with a conventional DP length of 60 d. Some cows have less milk production loss than other cows after applying no DP or a short DP. The aim of this study is to evaluate which cow characteristics are associated with the amount of milk production losses following no DP or a short DP (30 d). Daily production information from the lactation before and after the DP was available from 161 dairy cows (54 cows with a 0-d DP, 51 cows with a 30-d DP, and 56 cows with a 60-d DP) from a research herd. Daily production (milk, fat, and protein) until 305 d in milk was estimated for all cows. Subsequently, total fat- and protein-corrected milk yield from 60 d before the expected calving date until 305 d in the following lactation (FPCMtotal) was estimated. A statistical analysis was performed to evaluate which cow characteristics were associated with limited or no production losses following no DP or a short DP, compared with a conventional DP length of 60 d. Average FPCMtotal was 9,341, 10,499, and 10,795 kg for cows with no DP, a 30-d DP, and a 60-d DP, respectively. The cow characteristics parity, daily milk production at 12 wk before the expected calving date, and reduction in daily milk production between 16 and 12 wk before the expected calving date were associated with production loss due to a short (30 d) or no DP. Compared with 60 d DP, multiparous cows had less production loss (987 kg) following no DP than primiparous cows (2,132 kg). The difference in FPCMtotal between the 3 DP groups was largest for cows with a low milk production (e.g., 10 kg/d) at 12 wk before the expected calving date. The greater the reduction in milk production between 16 and 12 wk before the expected calving date, the larger the difference in FPCMtotal between the 3 DP groups. The difference in FPCMtotal between cows with no DP and 60 d DP at a reduction in milk production between 16 and 12 wk of 10% was 665 kg, whereas this difference was 1,138 kg at a reduction of 70%. The cow characteristics found can be used to select cows for specific DP lengths in a decision-support model to support the farmer on the economic optimal DP length for each individual cow. Output of such a decision-support model can be, for instance, to advise a 30-d DP for multiparous cows with high milk production (e.g., 25 kg/d) at 12 wk before the expected calving date. 相似文献
7.
Records of cattle slaughtered at two Chilean slaughterhouses (SLH1 and SLH2) were used to determine prevalence and risk factors for carcasses with bruises. Bruise prevalence amounted to 12.3% but differed between slaughterhouses (20.8% for SLH1 and 8.6% for SLH2 respectively). Bruise severity grade 1 (mild) was most frequently recorded. The type of the animal, source of animal, the level of fat cover and lairage time were associated with the presence of bruises. Older categories of animals and animals that pass through a market before being moved to the slaughterhouse are more prone to show bruises. The results also indicate that under the reported Chilean circumstances animals that have longer lairage times (over 12 h) have a significantly reduced risk for bruises, except for oxen. Presence of bruises is also significantly associated with increased carcass pH values. 相似文献
8.
An analysis of psychometric and Piagetian assessments of children's mental ability led to the prediction that the relation between these 2 kinds of assessments diminishes as children advance in age and stage level. The prediction was confirmed. A high correlation was found between MA (WISC scores) and progression toward Piaget's stage of concrete operations among 52 middle-class 6-8 yr olds, but the correlation was nonsignificant between MA and progression toward Piaget's stage of formal operations among 56 middle-class 10-12 yr olds. Alternative explanations of results are considered, and additional evidence is discussed which suggests that, although IQ is not related to the emergence of formal operations in preadolescence, the full development and/or maintenance of formal functioning during adulthood bears a relation to those educational and cultural advantages associated with higher IQs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Retzlaff D Phebus R Nutsch A Riemann J Kastner C Marsden J 《Journal of food protection》2004,67(8):1630-1633
A laboratory-scale vertical tower steam pasteurization unit was evaluated to determine the antimicrobial effectiveness of different exposure times (0, 3, 6, 12, and 15 s) and steam chamber temperatures (82.2, 87.8, 93.3, and 98.9 degrees C) against pathogens (Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria innocua) inoculated onto prerigor beef tissue. Samples were collected and microbiologically analyzed immediately before and after steam treatment to quantify the effectiveness of each time-temperature combination. The 0-s exposure at all chamber temperatures (cold water spray only, no steam treatment) was the experimental control and provided < or = 0.3 log CFU/cm2 reductions. Chamber temperatures of 82.2 and 87.8 degrees C were ineffective (P > 0.05) at all exposure times. At 93.3 degrees C, significant reductions (> 1.0 log CFU/cm2) were observed at exposure times of > or = 6 s, with 15 s providing approximately 1 log cycle greater reductions than 12 s of exposure. The 98.9 degrees C treatment was consistently the most effective, with exposure times of > or = 9 s resulting in >3.5 log CFU/cm2 reductions for all pathogens. 相似文献
10.
Experiments were performed to assess the reduction of Campylobacter spp. and Escherichia coli in commercial broiler carcasses by postchill dip applications of acidified sodium chlorite. Carcass rinses were collected before the inside-outside-bird washer (IOBW), post-IOBW, postchill, and after the postchill application of acidified sodium chlorite. Prevalence and counts of Campylobacter spp. and E. coli were determined. The mean values for Campylobacter spp. and E. coli counts differed significantly at sampling sites. The IOBW reduced the bacterial counts significantly in only one experiment. The chiller reduced Campylobacter counts significantly in both experiments but failed to significantly reduce the counts of E. coli in one experiment. No major reduction in the prevalence after enrichment for Campylobacter spp. was detected post-IOBW or postchill. However, a significant reduction in Campylobacter spp. and in E. coli counts and Campylobacter spp. prevalence was seen after the postchill application of acidified sodium chlorite. These results demonstrate that the antimicrobial effect of acidified sodium chlorite applied postchill may be used to significantly reduce Campylobacter spp. and E. coli in commercial broiler carcasses. Postchill systems may eventually be used in different applications, such as mist, spray, or bath, which could be applied closer to the final stages in processing. 相似文献