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Decision support systems (DSSs) are indispensable tools in preparing a forest management plan for a better combination of multiple forest values. This study attempted to develop and explain a stand-based forest management DSS (Ecosystem-based multiple-use forest planning [ETÇAP]) comprising a traditional simulation, linear programming (LP), metaheuristics and geographic information system. The model consists of five submodels; traditional management approach to handle inventory data, an empirical growth and yield model, a simulation to conceptualize management actions, a LP technique to optimize resource allocation and a simulated annealing approach to directly create a spatially feasible harvest schedule. The ETÇAP model has been implemented in a comparative two case study areas; Denizli–Honaz and Akseki–Ibrad?. Both simulation and optimization models outperformed to the traditional management plan. The periodical change of growing stock, allowable cuts, carbon sequestration and water production are used as performance indicators. The results showed that more amount of wood could be harvested over time compared to traditional level of harvesting. It could be concluded that various management strategies allowed managers to stimulate more decision options for better outputs through intertemporal trade-offs of management interventions as the model provided tools to quantify forest dynamics over time and space. Challenges exist to establish the functional relationships between forest structure and values for better quantification and integration into the management plans.  相似文献   
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从强度安全性的角度出发,综合运用了概率密度函数联合积分法与功能密度函数积分法,整理并推导了汽车零部件的对数正态模糊可靠度计算公式,即应力、强度都为对数正态分布,隶属度函数为k次抛物线分布时的模糊可靠度计算公式;通过VB编程实现数值解的计算,根据输入的原始数据、原函数与积分区间的特点进行积分变换,然后利用中点公式积分法与龙贝格求积法进行积分计算。本程序可直接应用于设计计算中,以提高汽车零部件的设计水平。  相似文献   
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In the present study, the effects of cefquinome, a 4th generation cephalosporin, on clinical, biochemical, haematological, and blood gas variables were investigated. Five healthy dogs were injected with cefquinome (1 mg/kg body weight, IM, daily) for 14 days. Negative effects of cefquinome on clinical, biochemical, and haematological variables were not observed, but it did change some blood gas variables.  相似文献   
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中早熟甜椒新品种中椒11号的选育   总被引:1,自引:0,他引:1  
Sweet pepper; Zhongjiao No.11; F1 hybrid.; 【摘要】 中椒11号为中早熟甜椒一代杂种。其母本91-126是利用国内甜、辣椒及国外的甜椒为材料,经杂交、回交、添加杂交和单株选择转育而成的抗病、优质甜椒高代自交系,父本92-2-3为早熟、结果率高、配合力强的甜椒高代自交系。中椒11号熟性中早,定植至采收40d(天)左右,产量3000~5000kg·(667m2)-1,抗逆性强,抗TMV、中抗CMV,耐湿热;适于华南南菜北运基地冬季种植或北方早春保护地及露地早熟栽培;果实长灯笼形,果色绿,肉厚,味甜,商品率高,耐贮运。已在广东、海南、山东、北京等地种植,推广面积达1500hm2。  相似文献   
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1. This study was conducted using male broiler chickens to determine the effects of ascorbic acid, aspirin, ascorbic acid+aspirin, vitamin E+selenium and ascorbic acid+aspirin+vitamin E+selenium supplementations on haematological parameters and serum superoxide dismutase concentration. 2. One hundred and twenty day-old male Hubbunt broiler chicks were randomly divided into 6 experimental groups of 20 chicks each and placed in different pens. Groups 2, 3, 4, 5 and 6 were given a diet supplemented with ascorbic acid, aspirin (in water), ascorbic acid+aspirin, vitamin E+selenium and ascorbic acid+aspirin+vitamin E+selenium, respectively for 45 d while group 1 was given a commercial broiler diet. 3. There was no significant effect of ascorbic acid, aspirin, ascorbic acid+aspirin, vitamin E+selenium supplementations on any of the haematological parameters (red blood cell, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin concentration, mean corpuscular haemoglobin) in broilers but ascorbic acid+aspirin+vitamin E+selenium supplementation significantly decreased the white blood cell counts. 4. In addition to this, ascorbic acid, aspirin, ascorbic acid+aspirin and ascorbic acid+aspirin+vitamin E+selenium supplementations had no significant effect on the serum superoxide dismutase level, but vitamin E+selenium supplementation increased the serum superoxide dismutase level.  相似文献   
8.
随着社会的发展,人们的工作和生活节奏也日益加快。与此同时,工作压力和心理压力也不断增加,在这种情况下,如不注意科学健身和均衡饮食,将会导致人们向亚健康群体过渡。新的饮食习惯、逐渐改善的卫生条件、全球旅行、药品用量和逐步增加的精神压力等都在影响着我们的健康并导致肠胃内菌群失调。肠胃中不均衡的菌群有可能引发免疫力降低、肠胃功能紊乱等常见问题。而益生菌可以有效维护肠道菌群生态平衡,形成生物屏障,抑制有害菌对肠道的侵蚀,提高人体免疫功能,减少毒素在体内的蓄积,防止疾病发生。1益生菌及其功能人体肠道中存在着数十亿种…  相似文献   
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The aim of this work was to synthesize chiral ionic liquids as chiral solvents for organic synthesis and to evaluate the phyto(eco)toxicity of the new products and starting N-alkylimidazoles and their potential environmental influence on soil and plants. Chiral ionic liquids containing anions such as Cl-, Br-, TsO-, PF6(-), NO3(-), CF3SO3(-), and (+)- and (-)-C6H5CH(OH)C(O)O- were synthesized using (-)-(1R)-6,6-dimethylbicyclo[3.1.1]hept-2-ene-2-ethyl [(-)-(1R)-nopyl] halides (X = Cl, Br) and tosylate in 62-100% yields. The chloride 7 and the nitrate 13 ionic liquids possessed a toxicity dependent on the applied concentration. The lowest concentration causing a distinct reduction in plant germination/growth was 100 mg/kg. Spring barley better tolerated the ionic liquids (200 mg/kg) than common radish (100 mg/kg). The nitrate liquid did not exhibit an inhibiting effect on the germination ability of seeds. The starting N-methylimidazole used in lower concentrations (1 and 10 mg/kg of soil dry weight) was not phytotoxic, in contrast to higher doses (>1000 mg/kg).  相似文献   
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