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1.
自走式微型旋耕机质量调查的模糊综合评判   总被引:1,自引:1,他引:0  
为了多方面评价微型旋耕机产品质量,满足用户需求,许多产品技术规范要求对产品用户进行质量调查,收集用户意见,获取微型旋耕机在使用中反映出的质量信息和用户对产品的潜在技术要求.由于调查的项目多数涉及定性的问题,比较模糊,不像产品质量性能检测那样,能获得被测对象的准确值,因而,对产品使用中反映出的质量问题进行综合评价非常困难.采用模糊数学综合评判理论,根据自走式微型旋耕机的特点,结合产品技术标准,选择了微型旋耕机的适应性、可靠性和经济性作为一级质量指标,以耕作效果、作业效率、田地适应性、平均无故障工作时间、平均故障维修时间、维修费用、单位油耗、产品价格作为二级质量指标,以耕深、耕后地表平整度、植被覆盖率作为耕作效果的三级质量指标.把模糊数学最大隶属度原理应用到评价中,构造综合评判模糊数学模型,通过实例计算和分析,验证了此模型的可靠性.研究结果对自走式微型旋耕机的产品选型和质量评价等具有重要的应用价值.  相似文献   
2.
马陆学名Julus bortersis属多足纲目科,分布于世界各国。国内各地都有分布,特别是温室和森林履盖率高,腐质层厚的地方均有发生。1发生危害特点2005年马陆在神农架松柏镇城镇、郊区、森林、农田、居民的住宅区、院内,靠近森林的公路、沟边暴发成灾。发生面积1 400m2,涉及城镇居民150余户,2 000人以上,布满城镇居民室内外的每一个角落,无处不有。在森林、农田、居民住宅潮湿的地方聚集成堆,在农田、森林居民居住的院内外、室内、外墙壁上呈均匀分布,有群集爬行的特点,每1m2最高有虫800~1 000头,平均1m2有虫500头以上,使城镇居民不能在家中生…  相似文献   
3.
Innovations in precision agriculture (PA) have created opportunities to achieve a greater understanding of within-field variability. However, PA adoption has been hindered by uncertainty about field-specific performance and return on investment. Uncertainty could be better addressed by using innovative analyses that provide insights into variability among fields and across a region. The objectives of this research were to: (1) generate a within-field soil clay-content variability index (VIc), (2) create a regional-scale growing-season precipitation variability index (VIp), and (3) integrate the soil and weather indices with the USDA NRCS soil erosion vulnerability index (SVI) to produce a final index that incorporated both variability and vulnerability (VVI). The interpretation of the outcomes represented by each objective supports unique decisions that land managers may consider for reducing uncertainty about implementing PA. All indices were derived using publically available information for Missouri, USA. The VIc was the ratio between the maximum and minimum clay content within fields. The VIp was calculated as the standard deviation of the total growing-season precipitation from 2006 to 2015. Significant clustering of VIc and VIp were observed along the Missouri River corridor, northeast and northwest Missouri. Fields with high VVI were mostly in the claypan soil region of northeast Missouri, and along a portion of the Missouri River dominated by loess soils on steep slopes. Southeast Missouri displayed the greatest diversity in soil and weather variability, but had low vulnerability. This research could be used as a decision-support tool to aid producers and PA service and product providers in determining where PA opportunities exist.  相似文献   
4.
甘肃省靖远小口枣生产情况调查   总被引:2,自引:1,他引:2  
杨斌  张可静 《中国果树》2007,(6):49-50,76
靖远小口枣原产于甘肃省靖远县石门乡小口村,以果大肉厚核小,甜脆清香而闻名遐迩。其果肉绿白色,质疏松,汁少,味甜,为优良的鲜食和制干兼用品种。曾于1988年在甘肃省枣鉴评会上获省优质产品称号;1991年在石家庄全国林果产品博览会获金奖;1996年在甘肃省名优特林果鉴评会上获银奖;2003年在中国首届沙产业博览会上获优质产品奖。20世纪90年代前,靖远小口枣仅分布在小口村附近的几个村,栽植面积较小,且零星栽植的植株占有一定的比例,生产规模小,不适应商品化生产的需要。为了发挥地方名优特产的资源优势,近20年来,靖远县将小口枣作为林果产业的…  相似文献   
5.
It has been suggested that certain morphological traits of Japanese pines function as resistance factors against the pine wood nematode (PWN), Bursaphelenchus xylophilus. The aim of this study was to verify this concept, and to determine the relationships between traits and resistance at both the individual and family levels. Relationships between survival rate and morphological traits of Pinus densiflora and Pinus thunbergii were studied after inoculation with PWN. Morphometric parameters used were height, basal diameter of the axis, and the number of branches from the axis. Three indices of relationships were analysed: (1) among individuals within a family (survival difference between smaller and larger morphometric populations within each family); (2) among individuals (correlation between each morphometric average and survival rate in quintile populations of all subjects within each pine species based on the order of morphometric values); and (3) among families (correlation between each morphometric average and survival rate in the family). Both significant and non-significant differences were detected within a family, indicating a need for macro techniques. Among individuals, a thicker axis and more branches were correlated with increased survival, indicating that they are resistance factors. However, these correlations were not significant among different families. These results indicate that morphological traits cannot be used to evaluate resistance at a family level, even if they are significant at an individual level. Further studies on traits associated with resistance should be conducted at a family rather than an individual level, to breed for Japanese pines with resistance to PWN.
Taro YamanobeEmail:
  相似文献   
6.
For nutritional purposes, a survey of the vitamin B6 levels from a variety of commercial presentations of table olives was carried out, taking into account the three main processing types (Spanish-style, directly brined, and ripe olives). The analysis was performed by HPLC, following the official French method for vitamin B6 determination in foodstuffs. In-house validation data for two commercial table olives showed that the method precision was good (coefficient of variation <6%) and recovery was quantitative (104% on average). There was a wide range of values for vitamin B6 in table olives (0–69.3 μg/100 g edible portion). The highest mean content was found in directly brined olives (33.9 μg/100 g edible portion) followed by Spanish-style (14.4 μg/100 g) and ripe olives (4.3 μg/100 g). On average, samples of the Gordal and Carrasqueña cultivars showed the highest vitamin B6 content in the case of Spanish-style olives, but in directly brined olives as well as in ripe olives the effect of cultivar was not statistically significant (p?相似文献   
7.
应用氟喹诺酮类抗菌动物专用药恩诺沙星水溶性粉剂对人工感染大肠杆菌病的雏鸡进行了治疗研究,用环丙沙星、阳性空白对照、阴性空白对照进行了比较。结果表明,60,30,10mg·L-1浓度的恩诺沙星可溶性粉剂的保护率分别为85.7%,77.1%,28.6%;环丙沙星20mg·L-1的保护率为74.3%,阳性对照组为11.4%,阴性对照组为100%.说明恩诺沙星对鸡大肠杆菌病有较好的疗效。  相似文献   
8.
To determine how stock abundance fluctuations of walleye pollock Theragra chalcogramma are related to variations in reproductive characteristics, the length at 50% maturity of the fish sampled off the Pacific coast of northern Japan from 1990 to 1999 was examined. In both sexes, the fish density increased, and the body length of age-3-5 fish decreased, but the condition factor and the age at 50% maturity showed no clear trend during this period. Male length at 50% maturity decreased, while value for females showed no clear trend. In both sexes, significant negative correlations were found between density index (combined age-3-5) and each body length at age-3-5. Significant positive correlations were seen between each body length at age-3-5 and length at 50% maturity in males. Positive correlation between body length at age-5 and length at 50% maturity was significant in females from 1990 to 1999, except for the samples in 1998. We suggest that the fish density might affect the length at maturity in males and possibly also in females.  相似文献   
9.
根据西畴县近17年(1990 ~ 2006年)的耕地资源和社会经济统计数据,运用多元统计分析中的主成分分析方法来分析西畴石漠化地区影响粮食增产的主导因素。结果表明,耕地质量对粮食增产的贡献率是69.85%,经济投入水平对粮食增产的贡献率是20.29%,说明耕地质量因素是西畴石漠化地区粮食增产的主导因素,而耕地质量的提高则主要得益于西畴土地整理模式的实施。在西畴石漠化地区后备耕地资源极为缺乏,以及因为经济建设发展需要耕地减少难以避免的情况下,只有坚定不移地推进土地整理,切实加强土壤改良和农田基础设施建设,从根本上改良耕地和提高耕地质量,才能提高耕地产出水平,进而提高粮食产量。  相似文献   
10.
Effects of sodium nitroprusside (SNP; nitric oxide donor) treatments on enhancement of secondary metabolites production, oxidative stress mediators (\(\mathrm{O}_{2}^{-}\)) accumulation and antioxidant defense enzymes of Potato Spunta Sp. suspension culture cells elicited by a fungal extract from phytophthora infestans mycelium. The obtained data confirmed the significant increase in various oxidative burst (super oxide anion, hydrogen peroxide and total glutathione) contents. The administration of various NO concentrations strongly decreased hydrogen peroxide concentration and superoxide anion levels. Moreover, the SNP treatments regulate elicitor-induced activation of phenylalanine ammonium-lyase and total soluble phenols accumulation. The highest concentrations of NO donor sodium nitroprusside potentiated elicitor-induced H2O2 production. On the other hand, the lowest H2O2 contents coincided with elicitation regulated various activities of enzymes superoxide-dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and Phenyl alanine ammonia lyase (PAL) activity, the decrease in H2O2 concentration was probably due to a direct reduction interaction of NO-H2O2. On the other hand, the addition of these previous NO treatments affects mRNA peroxidase gene expression using RT-PCR techniques. In general, the addition of lower concentrations of nitric oxide reduce the mRNA peroxidase activity on contrary, the higher concentrations induced the mRNA peroxidase activity, which induce the hypersensitive reactions against fungus infection.  相似文献   
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