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1.
The Unsteady Irrigation Water Distribution and Consumption (UIWDC) model is applied to analyze causes of uneven water distribution between the upstream and downstream beneficial areas of the Mae Lao Irrigation Scheme (MLIS). The uneven water distribution may be caused by inadequate water distribution facilities or improper operation rule; therefore, its causes are examined systematically and quantitatively from the aspects of “water allocation” and “operation rule”. The water allocation is considered focusing on the dry season irrigation, where equity and efficiency should be especially balanced because of the scare water resources. The “EQTY index” (the equity index) is defined to widen the range of consideration between the equity and the efficiency, instead of alternative judgment of which has a priority. The operation rule for facilities in the MLIS is assumed considering their capacities, and two coordinate values of “ineffective spillage” and “water deficit” in the scheduled areas are incorporated into operation rule to quantitatively diagnose the system performance. As a result, the original causes of uneven water distribution will presumably be identified. The informative and quantitative results are utilized to set a new benchmark performance of the MLIS for the water distribution. It can be described by the “Expected Ratio of Irrigable Area” (ERIA) and “Present Ratio of Irrigable Area” (PRIA). Based on this standard, the general recommendations can be more concretely proposed to raise the water distribution performance of the MLIS such as by improving distribution facilities and/or by installing vertical pumps.  相似文献   

2.
We can only use color numbers, color values and design to describe the color pattern of printed fabrics, which is different from woven fabrics with yarn disposition and texture as pattern determinants. Since most printed fabrics contain many different patterns nowadays, we need more than words and simple methods to describe the color patterns. The complication in pattern identification has made the analysis and comparison difficult and will have to be conducted manually. The automatic computer color separating system for printed fabrics proposed in this paper uses unsupervised learning network to automatically separate printed colors. The system first uses color scanner to pick the image of the printed fabrics and stores it as digital image. Then, it uses wavelet transformation to minify the fabric image to reduce the calculation load of color separation and also reserve the printing structure and color distribution of the original image. It also uses LAB color model to acquire characteristic value of the colors and the Self-Organizing Map Network (SOMN) to conduct color separation. According to our experimental results, this system can rapidly and automatically complete color separation and identify repeating patterns for printed fabrics’ images.  相似文献   

3.
These days consumers’ various demands are accelerating research on apparel manufacturing system including automatic measurement, pattern generation, and clothing simulation. Accordingly, methods of reconstructing human body from point-clouds measured using a three dimensional scanning device are required for apparel CAD system to support these functions. In particular, we present in this study a human body reconstruction method focused on two issues, which are the decision of the number of control point for each sectional curve with error bound and the local knot removal for reducing the unusual concentration of control points. The approximation of sectional curves with error bounds as an approximation criterion leads all sectional curves to their own particular shapes apart from the number of control points. In addition, the application of the local knot removal to construction of human body sectional curves reduces the unusual concentration of control points effectively. The results may be used to produce an apparel CAD system as an automatic pattern generation system and a clothing simulation system through the low level control of NUBS or NURBS.  相似文献   

4.
A total of 112 named cultivars and advanced breeding lines were assayed through horizontal starch electrophoresis to test the utility of isozyme loci as a means to objectively identify potato cultivars. Both leaf and tuber tissue were sampled in thirteen enzyme systems. Two buffer systems (Histidine-citrate, pH 5.7 and Lithium-borate, pH 8.3) were used to resolve 16 isozyme loci, of which 14 were scorable without progeny testing. A total of 43 scorable allozymes were detected. All cultivars or advanced breeding lines that were the result of hybridization were discriminated by their sum electrophoretic pattern, whereas, sports (i.e., Russet Burbank vs. Burbank) or line selections (i.e., Norgold Russet “M1” vs. “M2”) have patterns that are identical to the original mother clone. The allelic diversity within and among cultivars indicate that horizontal starch electrophoresis offers an objective means to discriminate sexually-derived potato cultivars.  相似文献   

5.
In previous work at the US Potato Genebank, RAPDs were used to detect large differences between genebank-conserved samples and their correspondingin situ populations re-collected from the wild. This work investigates one possible explanation for these differences: a large genetic change in the sample when it undergoes “domestication” by a forced sexual seed increase and subsequent adaptation to cultivation in the genebank. However, when 11Solanum fendleri and 17S. jamesii populations were collected from the wild and compared to their sexual progeny generated at the genebank, no significant differences in RAPD finger-prints were detected. These results show that theory of “genebank domestication” is not supported. However, when plants of one pair of populations were tested individually, the seed increase population was significantly more heterogeneous than its clonally collectedin situ parents. Thus, while genebank populations have the same genes as their wild counterparts, they may contain genotypes not present in the wild.  相似文献   

6.
A software system has been developed that designs garments made of figured fabrics and arranges the flat patterns on the fabric automatically. A series of image analysis techniques were used to find the repeat unit images of figured fabrics. Three-dimensional garment drape simulation was used to design garments using those repeat unit images as texture maps. Finally, a pattern nesting system was developed to arrange numerous flat garment patterns quickly keeping the continuity of the figures on them. This method could contribute to the increase of the reliability as well as the reduction of production cost by eliminating the unnecessary trial-and-error based processes.  相似文献   

7.
为明确相同施肥量条件下木薯-花生间作与花生单作的成熟期根际土壤细菌群落特征差异,以木薯品种 华南205和花生品种粤油200为试验材料,设计2个施氮水平(施氮、不施氮)和3种种植模式(木薯单作、花生单作、 木薯间作3行花生),采用高通量测序技术,研究了施氮和木薯间作对成熟期花生根际土壤细菌群落结构的影响。 结果表明,在相同施肥量条件下,木薯间作花生模式的土地当量比大于1,表现出间作优势,土地利用率提高49%~ 60%。成熟期花生根际土壤细菌4个优势类群依次为Chloroflexi、Proteobacteria、Actinobacteria和Acidobacteria,合计 比例84.42%~84.59%。花生根际土壤细菌的属数量共477个。施氮和木薯间作对花生根际土壤细菌的α多样性无 显著影响。木薯间作显著降低了Proteobacteria的相对丰度,降幅18.12%。在相对丰度排名前30的菌属中,不同处 理组合间TK10 和Roseiflexus 的差异达显著水平;施氮显著降低了菌属Candidatus_Solibacter、Acidimicrobiales 和 Amycolatopsis的相对丰度,降幅分别为41.18%、33.11%和71.98%。冗余分析表明,有效磷、pH显著影响细菌花生根 际土壤属水平群落组成。本研究结果为明确间作体系中花生根际微生态环境提供理论依据。  相似文献   

8.
An apparatus was developed to dig a trench and line it with plastic as a means of controlling the Colorado potato beetle. The apparatus was based on the concept of a plastic mulch laying device used by the market garden industry. The plastic lined trenches were “V” shaped in configuration with an average width at the top of 740 ±17 mm and a depth of 223±12 mm. Controlled experiments under field conditions demonstrated that trenches produced by the “Beetle Excluder” retained 95% of the beetles trapped. The trenches survived the weathering of a full season without requiring any maintenance.  相似文献   

9.
The objective of this study was to produce wholegrain wheat flour on a laboratory-scale with particle size distributions similar to commercially-milled samples without re-milling the bran. The moisture contents of four hard winter wheat cultivars were adjusted to 7.29–7.98% (by drying), 9.00–10.6% (“as is”), and 15.6% (by tempering) prior to milling into wholegrain flour. The moisture treatments appeared to affect the partitioning of wholegrain flour particles into each of three categories: fine (<600 μm), medium (600–849 μm) and coarse (≥850 μm). When the distributions of particles were grouped into these categories, wholegrain flours made from dried and “as is” wheat fell within the values for commercial wholegrain flours, while that from tempered wheat contained more coarse particles than even the coarsest commercial wholegrain flour. Loaf volumes and crumb firmness were not significantly different between bread made from wholegrain flour that had been produced from dried or “as is” wheat, but loaf volume was significantly lower and bread crumb firmness was significantly higher when wholegrain flour from tempered wheat was used. These results show that wheat may be milled without tempering to produce wholegrain flour with particle size similar to some commercially-milled flours without needing to re-grind the bran.  相似文献   

10.
Several studies have considered maize canopy as a homogeneous medium with a random leaf orientation distribution. Recent studies, however, have detected that maize leaf orientation in the horizontal plane (i.e., leaf azimuth distribution) can react filling empty spaces (e.g., intra-row or inter-row) due to plant spatial arrangement. “Rigid” genotypes present a random distribution of leaf azimuth, independent of planting pattern. “Plastic” genotypes have the ability to modify leaf orientation. They generally present a random leaf azimuth distribution under square planting patterns, but tend to align their leaves perpendicularly to the row direction under rectangular planting patterns. We used three-dimensional models to reconstruct canopy architecture, mimicking these two behaviors. We simulated mid-day (maximum sun elevation 79.4° and 65.3°) and daily light interception of fully developed canopies at various plant densities (3, 9 and 12 plants m−2) and row spacings (0.35 and 0.70 m), and compared the results of these simulations with data from a field experiment. Simulations and field measurements showed that canopy behavior (plastic or rigid) has a significant (P<0.05) effect on light interception. Plastic canopies in a rectangular plant spatial distribution were able to increase (6–10% around mid-day), or maintain (during a day) similar light attenuation coefficients (k) to those under square planting patterns. In rigid canopies, on the contrary, there was a reduction in k (10–12%) when grown under rectangular planting patterns, both at mid-day and during a day. Our results suggest that the plasticity of maize canopy, based on leaf re-orientation, results in similar daily light interception values in different inter-row distances.  相似文献   

11.
Protein contamination on refuge kernels due to cross-pollination from Bt corn to non-Bt corn ears is a major concern in the use of a seed mixture refuge strategy (“RIB”) for resistance management of ear-feeding pests. In this study, occurrence, distribution, and ear damage of the corn earworm, Helicoverpa zea (Boddie), were evaluated in three planting patterns of non-Bt and Bt corn plants containing Genuity® SmartStax™ traits. The three planting patterns were 1) pure stands of 27 Bt plants; 2) pure stands of 27 non-Bt plants; and 3) one non-Bt plant in the center surrounded by 26 Bt plants. A total of six trials were conducted in open field conditions with natural infestations in 2011 and 2012. Egg populations of H. zea were distributed randomly or uniformly, and the number of eggs laid was similar between Bt and non-Bt corn ears regardless of the planting patterns, suggesting that females of H. zea have no egg-laying preference between Bt and non-Bt plants. Bt corn plants containing Genuity® SmartStax™ traits were equally effective in the control of H. zea in pure stands of Bt corn and “RIB” plantings. Occurrence of larvae and ear damage on Bt corn were significantly lower than on non-Bt plants and there were no significant differences between pure stands of Bt and “RIB” plantings across all trials. However, the limited numbers of live larvae in the pure stands of Bt plants were distributed non-randomly, suggesting a possibility of uneven expression of Bt proteins or elevated larval movement in the pure stands of Bt plants. Larval occurrence (3rd–5th instars) and ear damage on the refuge ears in “RIB” plantings were similar to or greater than found on ears of pure stands of non-Bt plants. However, more studies are needed to understand the effect of pollen movement on the full life cycle of H. zea before a final conclusion on the refuge function of RIB planting can be made.  相似文献   

12.
种业是农业发展的芯片,其发展质量是决定粮食安全的关键。本文应用产业组织理论中“结构-行为-绩效”的分析范式,构建了我国杂交稻主产区种业的产业组织分析框架。从市场结构、市场行为和市场绩效的角度,对杂交稻主产区种业的经营规模、市场销售、运营模式、育种体系、营销渠道、价格分布及区域格局等进行分析。最后,基于“完善育种体系,加强资源整合;协调种企上中下游渠道,促进产内合理分工;提高行业管理水平,适度引导种企集群发展”等方面提出我国杂交稻种业发展的优化路径。  相似文献   

13.
《Field Crops Research》2004,87(1):23-34
The Osborne protein fractions of seeds of 17 Lupinus albus cultivars from different regions in Portugal (obtained from plants grown at the same location) were analysed. The objective of this work was to examine the variability in the seed protein fractions of such a L. albus germplasm sample in order to disclose existing genetic relationships and to obtain information useful for a breeding program. Globulins and, interestingly, the fraction extracted with NaOH (“glutelins”) were the major seed protein constituents. The several protein fractions were separated by electrophoresis (reducing SDS polyacrylamide gel electrophoresis) and the patterns examined by multivariate analysis. Bands of “glutelins” together with those of glycosylated polypeptides were found to have the highest discriminating capacity. Lupin populations were grouped according to their clinal geographical distribution from north (small-seeded, higher plant architecture and later flowering type) to south (large-seeded, shorter and early flowering type). It is also possible that polypeptide patterns could reflect microclimatic specificities related with altitude and temperature. In fact, one cultivar from the south but from high altitude was grouped with the north plant types adapted to colder and wetter weather, whereas two cultivars from a warmer north region were grouped with the southern types. The results show, in addition, that a general correlation exists between cultivar early flowering characteristics and higher amounts of both total seed protein and glutelins, and lower glutelin glycosylation. Since high seed protein content and early flowering are important aims of lupin breeding programs, these findings on the seed protein fractions could stimulate and direct future research in lupin improvement.  相似文献   

14.
为了探索适合北方寒区马铃薯(Solanum tuberosum L.)种植的测土配方施肥技术,对比了依据不同参数建立的施肥模式对马铃薯产量及经济效益的影响。依据"3414"试验获得的数据,采用土壤有效养分校正系数法、地力差减法及回归方程拟合求得的一元二次方程建立了3种施肥模式,对比试验表明,通过回归方程即氮(N):Y=25 400.7+166.5 N-0.35 N2(R2=0.958),磷(P):Y=35 669.7+181.7 P-2.2 P2(R2=0.948),钾(K)??Y=32 714.5+107.2 K-0.4 K2(R2=0.997),建立的最施肥模式获得的产量及经济效益分别较当地常规施肥处理高7.8%和2 138元/hm2,适合北方寒区马铃薯栽培。  相似文献   

15.
In this study, electrical properties and data transmission characteristics of 75D PET/silver composite filaments were measured and analyzed in order to explore the feasibility of “digital textiles” in terms of resistance, resonance frequency, dB loss, and Bandwidth. Those characteristics were measured and compared according to measurement length (10~50 cm) and number of strands (1~10) in order to provide a design guide line for smart clothing. According to the measurement results, electrical characteristics of conducting fiber can be enhanced by increasing the number of fiber strand. It was also demonstrated that multiple resonances could occur from conducting fiber when the fiber lengths are varied. Finally, it showed the delay time of conducting fiber reached the saturated value when the number of fiber strand exceeded five.  相似文献   

16.
The use of tissue culture techniques for the international movement of potato clonal germplasm was studied. “Multi-meristem” cultures were established from virus-free plants by procedures described earlier by the authors. Well developed plantlets, regenerated aseptically from “nodal cuttings” of shoots produced in multi-meristem cultures, were used for international transfer. The medium contained the Murashige-Skoog mineral and vitamin components, with 2% sucrose, and was supplemented with 2 mg/l calcium pantothenate and 0.2 mg/l gibberellic acid. The cultures survived the mail shipment when 1% agar medium and small test tubes were used; polystyrene containers reduced damage due to abrupt temperature changes. At the receiving end, higher survival rates during the recovery of plants was achieved through potting of plantlets regenerated from nodal cutting cultures. A total of 43 pest and disease-free potato clones have been distributedin vitro from CIP to 10 different countries. The training of technicians from developing countries played an important role in the application of these methods.  相似文献   

17.
《Plant Production Science》2013,16(3):359-364
Abstract

A priming method called sand priming was developed using sand as a priming solid matrix. The effect of sand priming on improving the field emergence performance of five super sweet corn cultivars was investigated. Sand priming significantly improved field emergence performance of all super sweet corn cultivars, and there was marked improvement by priming at 20ºC for 24 hr. After sand priming at 20ºC for 24 hr, field emergence percentage (FEP) of “Green Superman”, “Huatian 1”, “Yangtian 1”, “Mitian 8”, and “Chaotian 43” was increased by 52.1%, 37.5%, 38.0%, 40.9%, and 33.3%, respectively. Their field emergence speed (FES) was 2.3, 1.8, 2.0, 2.0, and 1.8 times of the control, respectively. To further elucidate the effect of sand priming on improving the field emergence performance of super sweet corn, we analyzed the membrane system integrity, α-amylase activity and protein content. Sand priming at 20ºC for 24 hr improved membrane system integrity and α-amylase activity in all super sweet corn cultivars. Furthermore, sand priming at 20ºC for 24 hr accelerated the degradation of embryo protein after 1 d germination in “Green Superman”.  相似文献   

18.
A tissue culture method for the rapid propagation of potatoes was studied using 38 varieties. At least 50 plantlets were regeneratedin vitro, in a sequential procedure, from a single isolated shoot tip. Rapid proliferation of shoots was enhanced by shake culture of previously differentiated organogenic cultures. These shoots in turn were used to regenerate complete plantlets by the culture of nodal sectionsin vitro. Culture initiation was more dependent on the variety than culture proliferation. The culture media contained the Murashige-Skoog basal components supplemented with 6-benzylaminopurine, gibberellic acid and naphthalene acetic acid. The system described, whereby high propagation rates can be achieved, was referred to as “multi-meristem” culture in contrast to the 1:1 rate normally obtained by the conventional, “single-meristem” culture. Evaluations of varietal stability, using both biochemical and morphological criteria showed no detectable changes due to thein vitro procedures. It is proposed to utilize the “multi-meristem” propagation technique for the conservation and international distribution of valuable clonal germplasm.  相似文献   

19.
本文介绍了前苏联利用本国红、绿茶等外品,在添加月桂叶碎片并用印度进口红茶进行增浓和用柠檬及伏牛花香精油加香处理后,加工而成的一种新型“CAAMO”颗粒茶的加工工艺流程,并对该产品的生化组分进行了分析。结果表明,“CAAM0”茶的含水量较其他茶低,儿茶素总量和表没食子儿茶素没食子酸酯(EGCG)、氨基酸、茶黄素、茶红素及芳香油的含量均较用同样原料加工成的红茶和其他茶样为高。无论是品质标准、生化成分含量或是在香气、滋味上,这种新工艺茶均超过了用同样原料加工成的其他茶类。经在前苏联格鲁吉亚共和国的茶厂引进这种技  相似文献   

20.
江西省冷害发生规律研究及水稻种植制度分析   总被引:1,自引:0,他引:1  
以江西省81个常规气象观测站1961-2012年的数据为基础,对江西省"倒春寒"及"寒露风"的发生规律进行分析,确定江西省适宜的水稻种植制度。分析结果显示,受全球气候变暖的影响,江西省"倒春寒"灾害气候发生风险总体呈降低趋势;在年平均气温和秋季平均气温升高的背景下,"寒露风"灾害气候发生的风险并没有降低,且有提前出现的趋势。因此,在水稻种植制度上,除了选用耐寒性好的品种外,还应合理扩大"中熟-中熟"的搭配种植模式,同时应尽量避免双季杂交晚稻的直播栽培。  相似文献   

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