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1.
Rapid socio-economic changes in some developing countries, including India, are creating new scopes for application of precision agriculture (PA). The implications of dramatic shifts for economic development, urbanization and energy consumption in some developing countries are immense. High-tech nature of traditional PA technologies developed in advanced countries created a real challenge for engineers to search suitable PA technologies for developing countries. It is expected that application of balanced soft and hard PA technologies based on the need of specific socio-economic condition of a country will make PA suitable for developing countries also.‘Soft’ PA depends mainly on visual observation of crop and soil and management decision based on experience and intuition, rather than on statistical and scientific analysis. ‘Hard’ PA utilizes all modern technologies such as GPS, RS, and VRT. Three components, namely,‘single PA technology’, ‘PA technology package’ (for the user to select one or combination) and ‘integrated PA technology’, have been identified as a part of adoption strategies of PA in the developing countries. Therefore, the objective of this paper is to find out the scope,the present status and the strategies for adoption of PA in India and in some developing countries. Application of PA in cash crop, plantation crop, etc. has been discussed. Application of some medium and low-tech PA tools such as chlorophyll meter and leaf colour chart in small farms has been included. This exhaustive review of the present status of PA in India and in some developing countries is expected to help to find out the adoption trend and direction of future research. Detailed strategy for the adoption of PA in India has also been proposed.  相似文献   

2.
Vendors‘Evaluating and Selecting is one study focu s in SCM and VMO. It is one of the very important operations management and can ad vance to implement the strategic aims. With the increase in use of total quality management and just-in-time concepts by a wide range of firms, the vendor sel ection question has become extremely important. It is necessary for firms to tak e part in the global competition and global manufacture. There are some decision -making techniques which can be used for evaluating and...  相似文献   

3.
Distribution and correlation analysis of wildfire and weather data in Japan   总被引:2,自引:0,他引:2  
To establish the wildfire danger rating system, detailed data of wildfire and some related parameters such as weather,population and tree species are required. In this paper, the raw data of weather parameters in Japan are first expanded into more detailed data. The daily value of each weather parameter in each third-level mesh, which is about 1 km × 1 km in size, from year 1999 to 2000 is calculated by means of inverse distance weighted interpolation. Expansion results for third-level meshes are demonstrated. Fire probability for each parameter is calculated and analyzed. It is found that the dependency relation of fire probability on some parameters have surprisingly regular format. The data calculated and analyzed in the paper and the results may act as a basic database for wildfire researchers, and are expected to promote the study of wildfire danger rating method and the development of such systems.  相似文献   

4.
Based on the theory of task-technology fit and literature review of mobile technology acceptance, a research model is presented based on the features of mobile technologies and the actual usage of mobile applications in business environments, which identifies the characteristics of mobile applications and fitting tasks. An exploratory case is studied to understand how ABC Company, Hong Kong, utilizes mobile selling applications in their sales management process. This study gives some managerial suggestions for enterprises to successfully use mobile applications.  相似文献   

5.
6.
Study on optimization of agent initial positions in land combat simulation   总被引:1,自引:0,他引:1  
The use of computational-intelligence-based techniques in the optimization of agent initial positions in land combat simulations is studied. A novel method for the reduction of support vectors in the support vector machine (SVM) is presented. The optimization on the width of the Gaussian kernel function and the combination of the SVM with the radial basis function neural network are performed in the proposed method. Simulation results show that the proposed method can improve the running efficiency drastically compared with that using the traditional SVM with the same precision. We also summarize and present some experiences and trends in the study on the optimization problem in land combat simulation.  相似文献   

7.
To understand the influences of actual sampling conditions on cotton fiber length testing, this article presents a theoretic study on the distributions and fibrogram of the sample taken out by sampler from ideal sliver at a certain angle. From the distributions expression it can be found that the size of the sampler and the sampling angle are important factors which affect sampling, but if the sampling width is narrow enough, the influence of the sampling angle on the distributions and fibrogram is small enough to be omitted. This is an important conclusion for sampling, in light of this, some suggestions for designing new type sampler are put forward.  相似文献   

8.
English is one of the most important foreign languages taught in universities in China. However, the results are often far from satisfactory. Students in universities often find it hard to express themselves in oral English after many years' study. Language is the most important means of human communication, and communication is the most important function of language. Therefore, the ultimate goal of language instruction is to equip the learners with the ability to use the language for communication. How to help undergraduates to improve their oral English becomes a big challenge for English teachers in China. Aiming to make some contributions to improve undergraduates' oral English, this paper explores some areas of concern which are believed to be the most critical to the success of Oral English Teaching (OET) in China. The first part of this paper discusses some existing factors that constrain OET in China. It followed by exploring some aspects on improving OET for undergraduates in China. It also provides some techniques/methods essential for OET teachers to employ in a classroom.  相似文献   

9.
A new supply contract based on sharing the sales profits as well as the cost of effort was developed to coordinate the supply chain with sales effort effects. The contract coordinates the supplier‘s actions with voluntary compliance; the contract is symmetric in the sense that both the supplier‘s and retailer‘s profits are linearly correlated and is more easily implemented in some situations. The impact of the retailer‘s loss aversion on his effort is investigated based on the contract. After characterizing the retailer‘s optimal solutions, this paper demonstrates that contrary to intuition, loss aversion weakens incentives for retailer‘s sales effort and the retailer‘s optimal effort decreases as the loss aversion increases.  相似文献   

10.
Progress of the theoretical studies on the ion sheath dynamics in plasma source ion implantation (PSII) is reviewed in this paper. Several models for simulating the ion sheath dynamics in PSII are provided. The main problem of nonuniform ion implantation on the target in PSII is discussed by analyzing some calculated results. In addition,based on the relative researches in our laboratory, some calculated results of the ion sheath dynamics in PSII for inner surface modification of a cylindrical bore are presented. Finally, new ideas and tendency for future researches on ion sheath dynamics in PSII are proposed.  相似文献   

11.
With the development of information technology, the fire safety assessment of whole structure or region based on the computer simulation has become a hot topic. However, traditionally, the concerned studies are performed separately for different objectives and difficult to perform an overall evaluation. A new multi-dimensional integration model and methodology for fire safety assessment were presented and two newly developed integrated systems were introduced to demonstrate the function of integration simulation technology in this paper. The first one is the analysis on the fire-resistant behaviors of whole structure under real fire loads. The second one is the study on fire evaluation and emergency rescue of campus based on geography information technology (GIS). Some practical examples are presented to illuminate the advantages of computer integration technology on fire safety assessment and emphasize some problems in the simulation. The results show that the multi-dimensional integration model offers a new way and platform for the integrating fire safety assessment of whole structure or region, and the integrated software developed is the useful engineering tools for cost-saving and safe design.  相似文献   

12.
The study of dyeability of the modified flax that uses dyeuptake to reflect its medifying effect is reported in this paper. The optimal technological condition is that the concentration of the modifying agent is 4 g/l, and NaOH is 6 g/l at liquor ratio of 1:30 for 60 min. at 85℃. Dyeabillity include uptake rate and color fastness. Dye-uptake of the modified flax is twice more than that of the unmodified. And their color fastness doesn‘t fall and some of them raise 0.5 - 1 level.  相似文献   

13.
To identify and study the Neolithic rice paddy in Shandong, eastern China, is not only an important issue in the development of Chinese rice agriculture, but also a key part of the study on rice spread in East Asia. Due to the limitation of archaeological materials and the research methods, there have been no discoveries about the Neolithic rice paddy in Shandong Province for a long time. Based on the identification of possible rice paddy by archaeological excavation, phytolith analysis of soil samples from this "paddy" has been systematically carried out and the results have shown a 4600—4300 years old rice paddy preserved at the Zhaojiazhuang site. This is the first examination and study of the rice paddy in North China by systematic phytolith analysis, which is very important for the Neolithic archaeological research and the study of the eastward spread of rice agricultural techniques in East Asia.  相似文献   

14.
In wireless network, call completion probability accounts for users‘ satisfaction since the admitted ongoing call may be interrupted during hand off process or even stay in the same cell when dynamically allocaring resource to calls hecause of the loss of resource. We focus on the relationship between call‘s completion probability and these interruptions and develop an analytical relationship model for homogeneous cellular networks based on probability analysis. Then assuming call‘s data source is modeled by on off traffic model, a two dimensional Markov process is established to compute these blocking and dropping probahilities for call‘s completion probability. The impacts of different new call arrival rate. call‘s traffic characteristic, user‘s mobility, call‘s holding time and call‘s admission threshold on call‘s completion are evaluated and compared through numerical examples. These results show that call‘s completion reaches its maximum value if making no difference between hand off call and new call in the case of light traffic load. But some resource should be reserved for the hand off call in high traffic scenario. The analytical model provides a basis for helping to set the call admission threshold.  相似文献   

15.
Rich paleoanthropological materials were unearthed in primary context from the Xinglongdong Cave in Fengjie County, Chongqing, South China, including a human tooth, numerous mammalian fossils, some stone artifacts and a Stegodon tusk exhibiting intentional engravings.Based on biostratigraphic data and uranium series dating,the cave was utilized as a human shelter about 120000-150000 years ago. It is the first time that an archaic Homo sapiens fossil has been unearthed from the Three Gorges Region. Engravings on the Stegodon tusk appear in groups,making up simple and abstract images. It is the earliest known engravings created by human beings; it exhibits great potential for the study of the origin of art and the development of ancient cultures in south China and bears important implications for the origin of modern humans in East Asia.  相似文献   

16.
The Einstein-Kahler metric for the Cartan-Hartogs domain of the second type is described. Firstly, the Monge-Ampère equation for the metric to an ordinary differential equation in the auxiliary function X=X(z,w) is reduced, by which an implicit function in X is obtained. Secondly, for some cases, the explicit forms of the complete Einstein-Kahler metrics on Cartan-Hartogs domains which are the non-homogeneous domains are obtained. Thirdly, the estimate of holomorphic sectional curvature under the Einstein-Kahler metric is given, and in some cases the comparison theorem for Kobayashi metric and Einstein-Kahler metric on Cartan-Hartogs domain of the second type is established.  相似文献   

17.
It analyses the Castanopsis carlesii, Camellia oleifera and Symplocos laurina populations‘ status and role in the Castanop.sis carlesii community basing on the study on the dominant population size structure, survival curve and dynamic. It reveals the Castanopsis carlesi population acts as a main role in the community which maintains the stabilization and renovation of the community. The populations of Camellia oleifera and Symplocos laurina act as a secondary position. The development and succession dynamics of dominant populations is also discussed. The management method is preliminary draw nout which offers a theoretical basis for the evergreen broad-leaved forest restoration and reconstruction in the lower hilly of the west edge of the Sichuan basin.  相似文献   

18.
SGT1 is a homologue of the yeast ubiquitin ligase-associated protein. It controls some protein degradation and activates defense pathway in plants. Cotton GbSGT1 gene (Gossypium barbadense) has been isolated and characterized in previous work. In this study, the plant expression vector pBSGT1 with bar gene as a selection agent was constructed and transgenic banana was obtained via Agrobacterium-mediated transformation with the assistance of particle bombardment and screened with PCR and Basta spreading on banana plant leaves. Estimating of transgenic banana plants for resistance to Panama wilt is in progress.  相似文献   

19.
The assessment of water security is an important content in the security management of water resources due to the fact that the state of water security directly affects both the sustainable development of regional economy and the improvement on the living quality of mankind. Grey associative analysis is introduced and applied to assessment of water security on the basis of grey characteristics of the assessment index system of water security. As a case study shows, grey associative analysis is used for evaluating water security of some provinces in China, and the satisfactory assessment results are obtained. The sequence of provinces in China with regard to water security from good to poor is obtained and, moreover, the water security level of each region is also confirmed. The results obtained accord with the actual state of each region. They are of practical significance and can be used to guide the management of regional water security and a sustainable development of the economy therein. At the same time, the results demonstrate that grey associative analysis provides a new method for assessing water security  相似文献   

20.
Some samples of sea shell animals stuck and multiplied on the bottom (beneath the seawater) coated with antifouling paints were collected at some domestic maritime spaces, and the content of heavy metals was detected through Inductively Coupled Plasma-Mass Spectroscopy. Meanwhile, comparison with sea shell animals was made on market for edible use. It shows that the content of heavy metals in internal organs of these marine animals is very high due to the large amount of copper and zinc contained in the antifouling paints, and this also does severely harm to sea environment and ecology. To study and develop the novel antifouling paints without copper(I) oxide is an imperative task which brooks no delay.  相似文献   

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