由于容迟网络(DTN)为满足极端情况下的端到端服务,使得容迟网络的路由机制复杂而且有别于现存的各种网络。基于洪泛的蔓延(Epidemic)路由,由于其广播特性,网络容易拥塞,基于效用(utility)的单复制路由机制,开销小,但是递交率不高,延迟...由于容迟网络(DTN)为满足极端情况下的端到端服务,使得容迟网络的路由机制复杂而且有别于现存的各种网络。基于洪泛的蔓延(Epidemic)路由,由于其广播特性,网络容易拥塞,基于效用(utility)的单复制路由机制,开销小,但是递交率不高,延迟大。文中根据这两种路由机制的优点,结合数据包产生的初期应尽最大努力递交这一思想,提出了一种可变效用的路由机制。通过ONE仿真器仿真了蔓延路由,PRoPHET路由,Spray and Wait路由机制以及文中提出的可变效用路由机制,结果表明文中提出的可变效用路由机制在递交率、平均延迟两个指标上表现的非常出色。展开更多
AIM To assess the efficacy and safety of a Chinese herbal medicine (CHM), Xiangsha Liujunzi granules, in the treatment of patients with functional dyspepsia (FD). METHODS We performed a randomized, double-blind, place...AIM To assess the efficacy and safety of a Chinese herbal medicine (CHM), Xiangsha Liujunzi granules, in the treatment of patients with functional dyspepsia (FD). METHODS We performed a randomized, double-blind, placebo-controlled trial with patients from three centers. Two hundred and sixteen subjects diagnosed with FD according to ROME. criteria and confirmed by upper gastrointestinal endoscopy and spleen-deficiency and Qi-stagnation syndrome were selected to receive Xiangsha Liujunzi granules or placebo for 4 wk in a 2: 1 ratio by blocked randomization. The subjects also received follow-up after the 4-wk intervention. Herbal or placebo granules were dissolved in 300 mL of water. Participants in both groups were administered 130 mL (45 degrees C) three times a day. Participants were evaluated prior to and following 4 wk of the intervention in terms of changes in the postprandial discomfort severity scale (PDSS) score, clinical global impression (CGI) scale score, hospital anxiety and depression scale (HADS) score, traditional Chinese medicine symptoms score (SS), scores of various domains of the 36-item short form health survey (SF-36), gastric emptying (GE) and any observed adverse effects. RESULTS Compared with the placebo group, patients in the CHM group showed significant improvements in the scores of PDSS, HADS, SS, SF-36 and CGI scale (P < 0.05 or P < 0.01). They also showed the amelioration in the GE rates of the proximal stomach and distal stomach (P < 0.05 or P < 0.01). CONCLUSION Xiangsha Liujunzi granules offered significant symptomatic improvement in patients with FD.展开更多
With the social and economic development,conflict among the shortage of resources,environmental destruction and economic development is ever more pronounced.In this context,the circular economy was gradually accepted....With the social and economic development,conflict among the shortage of resources,environmental destruction and economic development is ever more pronounced.In this context,the circular economy was gradually accepted.Guided by sustainable development concept and promoted by six external forces,tourism circular economy take tourism micro-cycle model as the core,implement in corporate and social levels,improve resource utilization efficiency,reduce tourism's adverse impacts on the surrounding environment through recycling,reducing and reusing resources,achieve economic,social and environmental development of the organic unity.展开更多
North and west China has abundant coal resources, however, such resources make these regions prone to serious mine fire disasters. Although the copious sand and fly ash resources found in these areas can be used as fi...North and west China has abundant coal resources, however, such resources make these regions prone to serious mine fire disasters. Although the copious sand and fly ash resources found in these areas can be used as fire-fighting materials, conventional grouting is expensive because of water shortage and loess particles. A new compound material(i.e., a sand-suspended colloid), which comprises a mineral inorganic gel and an organic polymer, is developed in the current study to improve the quality of sand injection and reduce water wastage when grouting. The new material can steadily suspend the sand, through the addition of a small amount of colloid yielding steady sand-suspended slurry. The process of producing the slurry is convenient and quick, overcoming the shortage of sand-suspending thickeners which need heat and are difficult to produce. The space work model based on the theory of the double-electric layer is established to study the suspended mechanism of the solid particles in the sand-suspended colloid.The dispersion effect of the sand-suspended colloid is demonstrated by the incorporation of the electrostatic effect by the double-electric layer and the steric hindrance effect on the sand particles, ensuring the stability of the colloid system and the steady suspension of sand particles in the sand-suspended colloid.Mechanical analysis indicates that the sand is suspended steadily under the condition that the rock sand particles stress on the lower part of the fluid is less than the yield stress of the colloid. Finally, the fireprevention technology of sand suspension was applied and tested in the Daliuta Coal Mine, achieving successful results.展开更多
Because of cloud computing's high degree of polymerization calculation mode, it can't give full play to the resources of the edge device such as computing, storage, etc. Fog computing can improve the resource ...Because of cloud computing's high degree of polymerization calculation mode, it can't give full play to the resources of the edge device such as computing, storage, etc. Fog computing can improve the resource utilization efficiency of the edge device, and solve the problem about service computing of the delay-sensitive applications. This paper researches on the framework of the fog computing, and adopts Cloud Atomization Technology to turn physical nodes in different levels into virtual machine nodes. On this basis, this paper uses the graph partitioning theory to build the fog computing's load balancing algorithm based on dynamic graph partitioning. The simulation results show that the framework of the fog computing after Cloud Atomization can build the system network flexibly, and dynamic load balancing mechanism can effectively configure system resources as well as reducing the consumption of node migration brought by system changes.展开更多
文摘由于容迟网络(DTN)为满足极端情况下的端到端服务,使得容迟网络的路由机制复杂而且有别于现存的各种网络。基于洪泛的蔓延(Epidemic)路由,由于其广播特性,网络容易拥塞,基于效用(utility)的单复制路由机制,开销小,但是递交率不高,延迟大。文中根据这两种路由机制的优点,结合数据包产生的初期应尽最大努力递交这一思想,提出了一种可变效用的路由机制。通过ONE仿真器仿真了蔓延路由,PRoPHET路由,Spray and Wait路由机制以及文中提出的可变效用路由机制,结果表明文中提出的可变效用路由机制在递交率、平均延迟两个指标上表现的非常出色。
基金Supported by the Major State Basic Research Development Program of China(973 Program)No.2013CB531703+1 种基金National Nature Science Foundation of China,No.81503567 and No.81673853the China Postdoctoral Science Foundation,No.2015M1227 and No.2016T90195
文摘AIM To assess the efficacy and safety of a Chinese herbal medicine (CHM), Xiangsha Liujunzi granules, in the treatment of patients with functional dyspepsia (FD). METHODS We performed a randomized, double-blind, placebo-controlled trial with patients from three centers. Two hundred and sixteen subjects diagnosed with FD according to ROME. criteria and confirmed by upper gastrointestinal endoscopy and spleen-deficiency and Qi-stagnation syndrome were selected to receive Xiangsha Liujunzi granules or placebo for 4 wk in a 2: 1 ratio by blocked randomization. The subjects also received follow-up after the 4-wk intervention. Herbal or placebo granules were dissolved in 300 mL of water. Participants in both groups were administered 130 mL (45 degrees C) three times a day. Participants were evaluated prior to and following 4 wk of the intervention in terms of changes in the postprandial discomfort severity scale (PDSS) score, clinical global impression (CGI) scale score, hospital anxiety and depression scale (HADS) score, traditional Chinese medicine symptoms score (SS), scores of various domains of the 36-item short form health survey (SF-36), gastric emptying (GE) and any observed adverse effects. RESULTS Compared with the placebo group, patients in the CHM group showed significant improvements in the scores of PDSS, HADS, SS, SF-36 and CGI scale (P < 0.05 or P < 0.01). They also showed the amelioration in the GE rates of the proximal stomach and distal stomach (P < 0.05 or P < 0.01). CONCLUSION Xiangsha Liujunzi granules offered significant symptomatic improvement in patients with FD.
文摘With the social and economic development,conflict among the shortage of resources,environmental destruction and economic development is ever more pronounced.In this context,the circular economy was gradually accepted.Guided by sustainable development concept and promoted by six external forces,tourism circular economy take tourism micro-cycle model as the core,implement in corporate and social levels,improve resource utilization efficiency,reduce tourism's adverse impacts on the surrounding environment through recycling,reducing and reusing resources,achieve economic,social and environmental development of the organic unity.
基金support of the research funds provided by the National Natural Science Foundation of China (Nos. 51304071, 51304073)the Open Projects of State Key Laboratory of Coal Resources and Safe Mining, China University of Mining & Technology of China (No. 12KF02)
文摘North and west China has abundant coal resources, however, such resources make these regions prone to serious mine fire disasters. Although the copious sand and fly ash resources found in these areas can be used as fire-fighting materials, conventional grouting is expensive because of water shortage and loess particles. A new compound material(i.e., a sand-suspended colloid), which comprises a mineral inorganic gel and an organic polymer, is developed in the current study to improve the quality of sand injection and reduce water wastage when grouting. The new material can steadily suspend the sand, through the addition of a small amount of colloid yielding steady sand-suspended slurry. The process of producing the slurry is convenient and quick, overcoming the shortage of sand-suspending thickeners which need heat and are difficult to produce. The space work model based on the theory of the double-electric layer is established to study the suspended mechanism of the solid particles in the sand-suspended colloid.The dispersion effect of the sand-suspended colloid is demonstrated by the incorporation of the electrostatic effect by the double-electric layer and the steric hindrance effect on the sand particles, ensuring the stability of the colloid system and the steady suspension of sand particles in the sand-suspended colloid.Mechanical analysis indicates that the sand is suspended steadily under the condition that the rock sand particles stress on the lower part of the fluid is less than the yield stress of the colloid. Finally, the fireprevention technology of sand suspension was applied and tested in the Daliuta Coal Mine, achieving successful results.
基金supported in part by the National Science and technology support program of P.R.China(No.2014BAH29F05)
文摘Because of cloud computing's high degree of polymerization calculation mode, it can't give full play to the resources of the edge device such as computing, storage, etc. Fog computing can improve the resource utilization efficiency of the edge device, and solve the problem about service computing of the delay-sensitive applications. This paper researches on the framework of the fog computing, and adopts Cloud Atomization Technology to turn physical nodes in different levels into virtual machine nodes. On this basis, this paper uses the graph partitioning theory to build the fog computing's load balancing algorithm based on dynamic graph partitioning. The simulation results show that the framework of the fog computing after Cloud Atomization can build the system network flexibly, and dynamic load balancing mechanism can effectively configure system resources as well as reducing the consumption of node migration brought by system changes.