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1.
A new incrementally growing neural network model, called the growing fuzzy topology ART (GFTART) model, is proposed based on integrating the conventional fuzzy ART model with the incremental topology-preserving mechanism of the growing cell structure (GCS) model. This is in addition, to a new training algorithm, called the push-pull learning algorithm. The proposed GFTART model has two purposes: First, to reduce the proliferation of incrementally generated nodes in the F2 layer by the conventional fuzzy ART model based on replacing each F2 node with a GCS. Second, to enhance the class-dependent clustering representation ability of the GCS model by including the categorization property of the conventional fuzzy ART model. In addition, the proposed push-pull training algorithm enhances the cluster discriminating property and partially improves the forgetting problem of the training algorithm in the GCS model.  相似文献   
2.
体重27kg左右杜长大生长猪96头,随机分为2组,每组设3个重复,分别饲喂添加0、10. 0mg/kg镉的玉米豆粕型饲粮,在体重约90kg时结束饲养试验,并对猪的生长性能、内脏器官的相对重量、血清相关激素指标进行分析。结果显示,添加10. 0mg/kg镉可显著影响猪的生长性能及内分泌水平,试验猪日增重降低18. 6% (P<0. 05),料重比升高15. 1% (P<0. 05);血清生长激素水平降低36. 5% (P<0. 05),而对T3、T4 水平无显著影响(P>0. 05);使肝重率、脾重率、胸腺重率、肠系膜淋巴结重率分别提高15. 1% (P<0. 05)、19.7% (P<0. 05)、30. 7% (P<0. 05)、33. 3% (P<0. 05),而对肾、心、胰、胆囊的相对重量无显著影响(P>0.05)。提示较低剂量镉(10. 0mg/kg)能影响猪的生长性能并可能由镉致生长激素水平降低所致。  相似文献   
3.
本实验对粪肠球菌的基础培养基碳、氮源进行筛选,同时对其生长所需的温度、时间和接菌量进行研究,优化出适合粪肠球菌生长最佳培养基,以提高活菌数量。在优化后的培养基中菌数分别达5.6×109CFU/mL、8.0×109CFU/mL。  相似文献   
4.
A ranking system for veterinary medicinal products and coccidiostat feed additives has been developed as a tool to be applied in a risk-based approach to the residue testing programme for foods of animal origin in the Irish National Residue Control Plan (NRCP). Three characteristics of substances that may occur as residues in food are included in the developed risk ranking system: Potency, as measured by the acceptable daily intake assigned by the European Medicines Agency Committee for Medicinal Products for Veterinary Use, to each substance; Usage, as measured by the three factors of Number of Doses, use on Individual animals or for Group treatment, and Withdrawal Period; and Residue Occurrence, as measured by the number of Non-Compliant Samples in the NRCP. For both Number of Doses and Non-Compliant Samples, data for the 5-year period 2008–12 have been used. The risk ranking system for substances was developed for beef cattle, sheep and goats, pigs, chickens and dairy cattle using a scoring system applied to the various parameters described above to give an overall score based on the following equation: Potency × Usage (Number of Doses + Individual/Group Use + Withdrawal Period) × Residue Occurrence. Applying this risk ranking system, the following substances are ranked very highly: antimicrobials such as amoxicillin (for all species except pigs), marbofloxacillin (for beef cattle), oxytetracycline (for all species except chickens), sulfadiazine with trimethoprim (for pigs and chickens) and tilmicosin (for chickens); antiparasitic drugs, such as the benzimidazoles triclabendazole (for beef and dairy cattle), fenbendazole/oxfendazole (for sheep/goats and dairy cattle) and albendazole (for dairy cattle), the avermectin ivermectin (for beef cattle), and anti-fluke drugs closantel and rafoxanide (for sheep/goats); the anticoccidials monensin, narasin, nicarbazin and toltrazuril (for chickens). The risk ranking system described is a relatively simple system designed to provide a reliable basis for selecting the veterinary medicinal products and coccidiostat feed additives that might be prioritised for residue testing.  相似文献   
5.
针对北方地区水稻育苗材料的技术要求,通过丙纶纺粘法非织造布与塑料薄膜物理性能,使用效果对比的试验,阐述了丙纶纺粘法非织造布用于水稻育苗的优越性。  相似文献   
6.
The aim of the present work was to study the effect of dietary supplementation of Euphorbia heterophylla on the quality of the Guinea pig meat. Forty guinea pigs were divided into two groups fed ad libitum during 46 days a Panicum maximum diet (Panicum diet) or a mixed diet (75% Panicum maximum + 25% Euphorbia heterophylla) (Paneuphorbia diet) to compare their effects on performances and on the composition of guinea pig tissues and carcass. Daily weight gain, liver weight, carcass yield, and the lipid content of both the carcass and the perirenal fat were significantly increased by the Paneuphorbia diet. Feeding Paneuphorbia diet increased (P < 0.05) the n-3 PUFA content in perirenal fat, muscle, liver and in the carcass and decreased (P < 0.05) the n-6/n-3 ratios in all these tissues and the carcass. In conclusion, this study shows that Euphorbia heterophylla is a source of n-3 fatty acids which can improve significantly the n-3 PUFA content of Guinea pig meat and carcass.  相似文献   
7.
通过面上调查、数据收集和实地调查相结合的方法,调查2020/21年榨季广西西南甘蔗苗情生长情况,面上调查包括查看资料,听取各市县糖业主管部门、企业及种植企业和蔗农的情况介绍;数据收集实地调查153个样点,其中新植蔗62个样点,宿根蔗91个样点;统计分析该蔗区甘蔗生产和苗期生长情况.结果表明,广西蔗区2020年1~5月平...  相似文献   
8.
Tomato plants were grown in the greenhouse in the soil, in confined beds, or in combined beds where the roots could also develop in the soil outside the bed. The beds were filled with compost based on clover grass hay, deep litter and peat and harvested in early summer and autumn in 2002 and 2003, and in the soil treatment the same compost was incorporated into the soil. The tomato fruit quality was assessed by sensory analysis and content of chemical components as, e.g. dry matter, soluble solids, citric acids and volatile components. The content of minerals was mainly determined to evaluate possible limitations in nutrient supply. Due to only minor effects of growing systems on sensory quality and chemical composition of tomato fruits it is concluded that it is possible to produce tomato fruits in confined and combined soil bed systems without any loss in eating quality. Actually the results indicate that a slight increase in quality of tomatoes from the confined and combined systems is obtained. The present result points to the fact that confined and combined growing systems may be new relevant commercial growing systems, in which the quality of tomatoes seems to be ensured, and in which nutrient loss and root diseases contamination can be reduced.  相似文献   
9.
The effect of dietary protein and gastrointestinal (GI) parasitism on growth and meat quality of lambs was assessed using 60 animals. The lambs were randomly allocated to one of three treatment groups (n = 20): group A, which served as control, group B that was regularly treated with albendazole and group C, which was given supplementary feeding with dietary protein. The three groups of lambs grazed into a pasture (Lolium perenne), which was contaminated with L3 larvae of GI nematodes. Lamb growth and condition score were assessed at 21-day intervals. After 126 days grazing all lambs were slaughtered and their carcasses were assessed for conformation and fatness and their ultimate pH was measured. Four carcasses from each group were randomly selected for meat quality measurements including physical analysis as well as colour, moisture, total fat, protein content and fatty acid composition. Parasitic challenge was assessed by means of faecal egg counts of lambs, pasture larvae and numbers of adult nematodes in the GI tract of lambs at slaughter. Growth rate of group B was higher (P < 0.01) than that of group A and resulted in significantly (P < 0.01) heavier carcasses. The produced carcasses had similar fatness, but differed significantly (P < 0.05), in their conformation; carcasses of group C scored higher than either those of group B or group A, respectively. There was a significant difference in the colour attributes (L*) with group A being significantly lighter (P < 0.05) and in pH (P < 0.01); Group B had the highest values. Carcasses of group C had the highest (P < 0.05) amounts of intermuscular fat compared to those of group B and A, respectively. The proportion of C16:1n-7 and C18:2n-6 was higher (P < 0.05) in subcutaneous fat tissue whereas the proportion of C18:0 was higher (P < 0.05) in muscle tissue. In conclusion, the present results showed that the increased protein content in the diet of growing lambs, grazing on a pasture infected with GI nematode larvae, resulted in the production of acceptable carcasses.  相似文献   
10.
浅谈儿童家具的实用性与成长性   总被引:8,自引:1,他引:8  
由儿童的特殊生理及心理特点,决定了儿童家具在设计和生产过程中要考虑更多的因素,比如实用性和成长性。实用性是儿童家具能更好地符合儿童日常的学习、休息、娱乐等活动的特性。成长性也是实用性的表现,具体是指儿童家具能符合不同年龄及身高的儿童使用,能伴随儿童成长。  相似文献   
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