On the spectrum-determined growth condition of a vibration cablewith a tip mass

We show that the spectrum-determined growth condition holds for the closed-loop system of a vibration cable with a tip mass and linear boundary feedback control. The optimal decay rate of the energy for a case left unsolved previously is determined, and the asymptotic expansion of the associated semigroup is obtained. As a consequence of the approach, we show, in a different point of view, the lack of uniform exponential stability of the system with only boundary velocity feedback control     

A MEMS Thermal Biosensor for Metabolic Monitoring Applications

This paper presents a microelectromechanical systems (MEMS) differential thermal biosensor integrated with microfluidics for metabolite measurements in either flow-injection or flow-through mode. The MEMS device consists of two identical freestanding polymer diaphragms, resistive heaters, and a thermopile between the diaphragms. Integrated with polymer-based microfluidic measurement chambers, the device allows sensitive measurement of small volumes of liquid samples. Enzymes specific to a metabolic analyte system are immobilized on microbeads packed in the chambers. When a sample solution containing the analyte is introduced to the device, the heat released from the enzymatic reactions of the analyte is detected by the thermopile. The device has been tested with glucose solutions at physiologically relevant concentrations. In flow-injection mode, the device demonstrates a sensitivity of approximately 2.1 muV/mM and a resolution of about 0.025 mM. In flow-through mode with a perfusion flow rate of 0.5 mL/h, the sensitivity and resolution of the device are determined to be approximately 0.24 muV/mM and 0.4 mM, respectively. These results illustrate that the device, when integrated with subcutaneous sampling methods, can potentially allow for continuous monitoring of glucose and other metabolites.     

Group interaction analysis in dynamic context.

Computer understanding of human actions and interactions is one of the key research issues in human computing. In this regard, context plays an essential role in semantic understanding of human behavioral and social signals from sensor data. This paper put forward an event-based dynamic context model to address the problems of context awareness in the analysis of group interaction scenarios. Event-driven multilevel dynamic Bayesian network is correspondingly proposed to detect multilevel events, which underlies the context awareness mechanism. Online analysis can be achieved, which is superior over previous works. Experiments in our smart meeting room demonstrate the effectiveness of our approach.     

Cross-Layer Optimization for State Update in Mobile Gaming

In a large-scale mobile gaming environment with limited wireless network bandwidth, efficient mechanisms for state update are crucial to allow graceful real-time interaction for a large number of players. By using the state updating threshold as a key parameter that bridges the resulting state distortion and the network traffic, we are able to study the fundamental traffic-distortion tradeoffs via both theoretical modeling and numerical analysis using real game traces. We consider a WiMAX link model, where the bandwidth allocation is driven by the underlying physical layer link quality as well as application layer gaming behaviors. Such a cross-layer optimization problem can be solved using standard convex programming techniques. By exploring the temporal locality of gaming behavior, we also propose a prediction method for on-line bandwidth adaptation. Using real data traces from a multiplayer driving game, TORCS, the proposed network-aware bandwidth allocation method (NABA) is able to achieve significant reduction in state distortion compared to two baselines: uniform and proportional policies.     

The forwarding indices of augmented cubes

For a given connected graph G of order n, a routing R in G is a set of n(n−1) elementary paths specified for every ordered pair of vertices in G. The vertex (resp. edge) forwarding index of G is the maximum number of paths in R passing through any vertex (resp. edge) in G. Choudum and Sunitha [S.A. Choudum, V. Sunitha, Augmented cubes, Networks 40 (2002) 71-84] proposed a variant of the hypercube Qn, called the augmented cube AQn and presented a minimal routing algorithm. This paper determines the vertex and the edge forwarding indices of AQn as and ²n−1, respectively, which shows that the above algorithm is optimal in view of maximizing the network capacity.     

食用级碱式碳酸镁生产工艺研究

研究了以工业级硫酸镁为原料生产食用级碱式碳酸镁的工艺条件及影响产品收率的主要因素。     

Photocatalytic effect of carbon-modified n-TiO2 nanoparticles under visible light illumination

The present research focused on wet process synthesis of visible light active carbon-modified (CM)-n-TiO₂ nanoparticles and their photocatalytic activity. The CM-n-TiO₂ was synthesized by hydrolysis of TiCl₄ in the presence of tetrabutylammonium hydroxide and also in the presence of glucose and sodium hydroxide. UV–vis spectra, X-ray diffraction (XRD), and FT-IR were used to characterize these photocatalysts. It was found that the CM-n-TiO₂ nanoparticles synthesized by hydrolysis with tetrabutylammonium hydroxide or with sodium hydroxide and glucose when subjected to extended aging and subsequent calcinations absorb well into the visible to near infrared region up to 800 nm and exhibit enhanced visible light photocatalytic activity on degradation of 4-chlorophenol. CM-n-TiO₂ synthesized using glucose as the carbon source generated 13-fold increase in the initial rate of photodegradation of 4-chlorophenol compared to those by regular n-TiO₂, whereas, it increased only eight-fold when tetrabutylammonium hydroxide was used as the carbon source.     

呼兰河流域2012年洪水特性分析

对2012年呼兰河流域的暴雨、洪水特性进行了分析,说明了变化规律,认识该流域水文特性,并对其成因及特性进行了归纳,为流域综合治理等提供科学的决策依据,其形成洪水主要是7月25—26日和7月28—29日的两次范围广、强度大的降雨过程。8月4日凌晨呼兰河秦家站出现洪峰,洪峰流量达到1 090 m3/s为2005年迁站以来第一位洪水。     

Stability study on naturally filling body in gob-side entry retaining

In the construction of the filling gob-side entry retaining in a lane, we utilize the self-slide natural phenomenon of a falling gangue in an inclined coal seam goaf. First, we put the falling gangue of goaf above the laneway and made it the main filling material by adopting the measurement of flexible supporting system combined with those of rigid supporting system. Then we made the filling material gunited and solidified to maintain the filling goal of the gob-side entry retaining beside the lane. Considering the law of energy conservation and law of pressure distribution for retaining the active and static soil of the wall, we analyzed the reliability of a gangue blocking facilities and the stability of the filling material in the lane. We analyze the figures to see the stability. The result shows that the gangue block supporting system is reliable, and has been successfully practically applied.