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Process control in oil extraction and processing is traditionally done by independent control loops and logic (sequence) controls. In the best case, all controls are located in one central control room. The operator’s task is to draw the right conclusions from the process conditions signalled to him, to coordinate, to plan and to keep logsheets. On the basis of this information, he can coordinate between control loops and optimize unit operations. With the application of modern microelectronic-based control systems (integrated control systems), it is possible to present the operator’s information on a higher level (e.g., yield figures and energy consumptions computed from basic data), to do computerized planning operations and updatings, and to retrieve data which are used as an input for accounting systems and management information systems. Underlying principles, means for implementation, as well as benefits (both proven and potential) are described. The available hardware and software packages hardly form any limitations; on the contrary, we must often limit ourselves to optimal use of the available tools and not fall into the trap of “maximal automation.” Our aim is not to automate and control as much as possible, but to use automation as one of the means to process oilseeds and edible oils with the highest possible efficiency. 相似文献
94.
There is limited information available on what is the most appropriate feeding method for growing dairy heifers. The objective of this study was to determine the effect of feeding method on the feeding behavior and diet selection of growing dairy heifers. Six prepubescent Holstein heifers (158.2 ± 4.0 d old, weighing 168.2 ± 15.7 kg), fed once per day for 1.0 kg/d of growth, were subjected to each of 3 treatments in 3 successive 7-d treatment periods using a replicated 3 × 3 Latin square design. Treatments consisted of feeding 2.02 kg/d dry matter of grain concentrate and ad libitum chopped grass hay as: 1) choice (grain concentrate and hay in separate feed bins), 2) top-dressed ration (grain concentrate placed on top of the hay in one feed bin), and 3) total mixed ration (TMR, grain concentrate mixed with hay in one feed bin). Dry matter intake (DMI) and feeding behavior were monitored for 7 d for each animal on each treatment, and feed sorting was monitored for the last 3 d of each treatment period. The provision of grain concentrate and hay in either a choice or top-dressed situation resulted in young dairy heifers rapidly consuming the grain concentrate portion of their ration in very few, large meals before consuming the hay portion of their ration. The provision of the 2 ration ingredients as a TMR increased the distribution of DMI over the day and reduced the amount of sorting (against long forage particles, and for short grain concentrate particles) by heifers. These results suggest that the provision of a TMR to growing dairy heifers, as opposed to feeding concentrate and hay as either a choice or top-dressed, promotes a more balanced intake of nutrients across the day. 相似文献
95.
Dairy cows are often overstocked. Some managers are now using “slick bunk” (i.e., feeding for 0% orts) management to save on feed costs, but this reduces the time that cows have access to feed. Both practices may increase competition and affect feeding behavior in dairy cows. The aim was to determine the effects of temporal and spatial restrictions on the feeding and competitive behavior of group-housed cows. Treatments were 2 levels of stocking (2:1 versus 1:1 cows:feed bin) and 2 levels of feed access time (14 versus 24 h/d access). Eight groups (each of 6 cows) were tested on each of the 4 treatment combinations for 1 wk, with treatment order assigned using a replicated 4 × 4 Latin square design. Dry matter intake (DMI), feeding time, and feeding rate were measured for the last 4 d of each week, and data were summarized daily and for the 2-h period immediately after the morning feeding. Displacements were recorded for 2 h after the delivery of morning feed (peak feeding period) and 2 h following the afternoon milking. The DMI did not decline when temporal access was restricted (27.0 vs. 25.7 ± 0.5 kg/d), and was not affected by overstocking (26.4 ± 1.9, mean ± SD). Cows with restricted temporal access spent less time feeding (190.9 vs. 207.9 ± 6.1 min). Overstocked cows that were temporally restricted had greater feeding rates during the day (156 vs. 137 ± 4 g/min) and especially during the peak feeding period (175 vs. 146 ± 4 g/min) compared with cows that were not restricted. In the peak feeding period, overstocked cows had reduced DMI (3.0 vs. 3.4 ± 0.1 kg/h) and feeding times (20.8 vs. 25.8 ± 1.0 min/h) and increased feeding rates (161 vs. 138 ± 4 g/min). Cows with restricted temporal access had greater DMI (3.9 vs. 2.6 ± 0.2 kg/h) and time spent feeding (27.3 vs. 19.2 ± 1.3 min/h) during the peak feeding period compared with cows that had continuous access to feed. Restricting temporal access in conjunction with overstocking resulted in the greatest increase in daily displacements (15.0 vs. 3.8 ± 1.4 displacements/d); the majority of these occurred during the peak feeding period. Adequate space and time to access feed is essential to minimize feed bunk competition in indoor group housing systems. 相似文献
96.
Proposes a new research orientation for population research, a psychology of population. This approach would include elements of social and developmental psychology (e.g., attitudes toward family planning, childhood socialization, sex roles, evaluation of different contraceptive methods, and family and group influences). Population psychology could integrate biological and social studies, provide a framework for studying the entire life cycle, and establish a methodology for evaluating micro- and macrosystems. The overall purpose of a psychology of population is presented as the ability to show (a) how biological variables are expressed in behavior and (b) the effects of basic drives on interpersonal, social, and cultural conditions and vice versa. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Dietary rapeseed/canola‐oil supplementation reduces serum lipids and liver enzymes and alters postprandial inflammatory responses in adipose tissue compared to olive‐oil supplementation in obese men 下载免费PDF全文
99.
There is a direct relationship between elevated somatic cell count (SCC) in an individual cow milk production and milk loss. This relationship has been used at the herd level to estimate an overall herd milk loss due to subclinical mastitis and to use recovery of this lost milk as a financial benefit to cover the cost of intervention strategies to improve milk quality. The objective of this study was to estimate the recoverable milk revenue on a per cow basis for herds moving from one herd average SCC level to a newer, lower level. Test-day records from 1,005,697 dairy cows in 3,741 herds between 2009 to 2019 were used. Milk yield loss for each cow in each herd on test day was estimated using a mixed effects regression equation, and then summed to estimated total herd milk loss. These herd average daily milk loss estimates were then related to the bulk tank SCC, and the distribution of underlying individual cow SCC were examined. The distributions in daily herd milk loss for various bulk tank SCC values were generated, and estimates of recoverable milk loss were generated to simulate a herd moving from their current bulk tank SCC to a new lower level. The results indicate that estimates of total herd milk yield loss vary with the distribution of cow-level SCC and parity within the herd, so it is imperative that milk loss be calculated on a per cow basis. Further, the recoverable milk loss estimates based on moving to a lower bulk tank SCC where milk loss is still occurring was relatively small compared with the traditional assumption that all milk loss would be recovered, and less than most herd owners and advisors would expect. 相似文献