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71.
0 IntroductionManystudieshavebeendoneonthesedimentdischargeinMt.Tanakami .Thosestudiesconcerntheamountofsedi mentsandfewdiscussionsabouttheprocessonly .Andthesedi mentyieldmechanismindevastatedslopeinMt.Tanakamiisnotfullyunderstood.Inordertorecordthewholeprocessofsoilero sionfromthebeginningofprecipitation ,totheendofsedimentmovement,asimulatingexperimentbyusingartificialrainiscon ducted .Basedonthisexperiment,andbyfurthercomparingwiththepreviousdataofsedimentsinthisarea,somebasicdataaboutc…  相似文献   
72.
1Introduction Now ,in orbitspacecraftsdeveloprapidlyinqualityandquantity,whilethegroundTT&Cresourceisrelativelylimi ted .Therefore ,torealizespacecraftautonomousnavigationandpositioningseemsespeciallytobeimportant.Itisoneoftheimportantaspectstoincreasethein orbitspacecraftself containedability . ExtensiveattentionshavebeenpaidtotheapplicationofGPSinthisarea,andquiteanumberofachievementshavebeengained ,butitisonlythebeginning . FortheutilizationofGPSinspacecraftnavigationandpo sitioning …  相似文献   
73.
Coverage layer coated in the internal wall of pipeline enables the friction drag to be reduced, the throughput and the gas transmission efficiency to be increased, the frequency of pigging and the number of the intermediate compressor station to be reduced, and the power consumption of the compressor to be decreased etc. The drag reduction is a high advanced scientific technique with outstanding economical benefit. The study and application of internal coating technique for drag reduction of 4000km trunk pipeline in West-East gas transmission pipeline (WEGTP) project are described, in which the main points are the drag reduction principle, coating process and the indoor study of this technique with own-decided knowledge property right at home.  相似文献   
74.
Industrial sectors that operate in uncertain environments - with demand variability, product seasonality and different industrialisation structures - need studies that enable identification and forecast trends. Therefore, the development of competitiveness extends beyond a company’s individual performance. Collective action, whether toward consumer markets, supplier markets, competitors and substitutes, can reinforce or help reformulate the current practices of an organisation, besides providing better results in the development of strategies and competitive positioning. Thus, clothing, the sector addressed in this work, is characterised by a long, fragmented, heterogeneous production chain, the competitiveness of which is linked to product differentiation. Therefore, the use of systemic approaches to study this sector is effective. In this sense, this research aims at adapting Systems Thinking and Scenario Planning (STSP) so that it supports the development and planning process in a given sector. Thus, this research applies STSP adapted to an analysis of the clothing sector in the northern region of Rio Grande do Sul State, Brazil. As a result, in academic terms, this research proposed and validated a method for analysing industrial sectors of the clothing industry. In the sectoral context, this research identified elements that leverage the sector’s competitiveness, besides generating knowledge and learning aimed at strengthening the sectoral structure identified, and fostering the formation of a new clothing cluster.  相似文献   
75.
Community indicators have been a frequent focus of the scholarly literature. There has been little exploration, however, in relation to rural communities, especially in developing countries. This reflects the special challenges associated with the complexity of rural systems, and the difficulties involved in developing appropriate and systemic indicators for rural communities. Identifying indicators that help the community to monitor progress towards sustainable outcomes requires a framework that is both practical and holistic. This paper introduces a participatory systemic framework for identifying community indicators, which respects the principles of complexity and honours the sense of ownership present in the communities. This framework is an iterative, sharing, co-learning engagement process that extends from creating a shared vision and extracting its core messages, to identifying indicators of progress and determining what actions to try. Importantly, this framework enables us to rank the indicators identified by communities with reference to ‘leverage points’, the best places to intervene in the social-environmental system for transformational change. This framework provides a potential pathway for sustainable rural development and perhaps also for organisations and urban communities.  相似文献   
76.
In this paper, adaptive event-based consensus of multi-agent systems with general linear dynamics is considered. A novel adaptive event-based controller and a state-dependent triggering function are proposed for each agent. The consensus can be achieved without the assumption that (A,B) is stabilizable. Furthermore, the Zeno-behavior of the concerned closed-loop system is also excluded under certain conditions. Finally, a numerical simulation example is presented to show the effectiveness of the theoretical results.  相似文献   
77.
78.
This paper studies an M/M/1 queueing-inventory system with batch demands. Customers arrive in the system according to a compound Poisson process, where the size of the batch demands for each arrival is a random variable that follows a geometric distribution. The inventory is replenished according to the standard (s,S) policy. The replenishment time follows an exponential distribution. Two models are considered. In the first model, if the on-hand inventory is less than the size of the batch demands of an arrived customer, the customer takes away all the items in the inventory, and a part of the customer’s batch demands is lost. In the second model, if the on-hand inventory is less than the size of the batch demands of an arrived customer, the customer leaves without taking any item from the inventory, and all of the customer’s batch demands are lost. For these two models, the authors derive the stationary conditions of the system. Then, the authors derive the stationary distributions of the product-form of the joint queue length and the on-hand inventory process. Besides this, the authors obtain some important performance measures and the average cost functions by using these stationary distributions. The results are illustrated by numerical examples.  相似文献   
79.
In this paper, a family of non-monomial permutations over the finite field \({F_{{2^n}}}\) with differential uniformity at most 6 is proposed, where n is a positive integer. The algebraic degree of these functions is also determined.  相似文献   
80.
This paper explores the investors’ feedback to the price change by modelling the price-related dynamics of trading intensity. A component decomposition duration modeling approach, called the component autoregressive conditional duration (CACD) model, is proposed to capture the variation of trading intensity across time intervals between price change events. Based on the CACD model, an empirical analysis is carried out on the Chinese stock market that covers different market statuses. The empirical results suggest that the CACD model can capture the price-related dynamics of trading intensity, which supports the existence of the feedback effect and is robust across different market statuses. The authors also study how the investors react to the price change by examining the driven factors of the price-related dynamics of trading intensity. The authors find that the trading can be triggered by the fast rise in the price level and the high trading volume. Besides, investors are more sensitive to the price change direction in the sideways market than in the upward or downward markets.  相似文献   
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