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A non-contact temperature measurement and recognition device based on OpenMV camera module and MLX90614 temperature recognition module is designed. OpenMV is used for identification and MLX90614 module is used for initial temperature measurement. The measured data can be compensated and posted on the LCD screen. Identity recognition adopts multi-template storage, LBP value and threshold value comparison and matching method, after multiple verifications, the accuracy rate reaches 94%. Temperature measurement adopts Kalman filter algorithm to reduce instrument error. The error range of measured object temperature after algorithm compensation is closed to 0.2 centigrade, and the error range of body temperature measurement is 1.7 centigrade. Finally, if the identification process fails or the temperature measurement value is higher than the preset value, the buzzer and LCD screen will issue a warning.

Acoustic mode investigation provides essential guidance in silent aero-engine designing by measuring pressure perturbations around the duct. Instead of mounting a full sensor array (FSA), compressive sampling (CS) feasibly achieves identical resolution with lower microphone requirement. In this paper, a generalized minimax-concave (GMC) regularized CS model is proposed as alternative to L1-norm regularized one for acoustic mode measurements, offering more accurate results by the use of fewer microphones. Improvement is guaranteed by the potential of GMC penalty due to sparsity inducing. Meanwhile the convexity of the cost function is also maintained via setting the scale matrix. It captures both advantages of nonconvex regularization and convex optimization. The effectiveness of the approach is validated on an aero-engine fan test rig. The tonal noise series are firstly separated from the sound pressure signals via cyclostationary analysis, thus amplitudes of tonal modes are estimated exactly. Two cases under different shaft speeds are conducted to estimate acoustic tonal modes, and results indicate that the proposed approach outperforms L1-norm regularized method in reconstruction accuracy. The effect of sensor number on reconstruction accuracy is also investigated, showing the proposed GMC method enables appropriate mode estimation from much fewer sensors.

Extreme events result in significant economic and social disruptions. As an important infrastructure, power transmission systems often have large-scale power outages during extreme events. In order to minimize the loss of power transmission systems under extreme events, this paper proposes a method to devise an optimal maintenance strategy for minimizing maintenance cost. Firstly, a fragility model is established and the Monte Carlo is used to assess the impact of extreme events on power transmission systems. Considering multiple component outages, even system splitting, a power system response model is developed to reflect the operation of power system. Taking into account the maintenance cost and reliability of systems, an optimized model is constructed to devise a post-disaster repair strategy for power transmission systems in a cost-effective manner. Finally, the IEEE 6-bus system is employed to verify the feasibility of the proposed method. In turn, the results provide a reference basis for power companies to carry out power transmission systems emergency planning and post-disaster repair.

The discharging method is most well-known for its central role in the proof of the Four Color Theorem. This proof technique was extensively applied to study various graph coloring problems, in particular on planar graphs. In this paper, we show that suitably altered discharging technique can also be used on domination-type problems. The general discharging approach for domination-type problems is illustrated on a specific domination-type problem, the double Roman domination on some generalized Petersen graphs. By applying this approach, we first prove that $\gamma _{dR}(G) \geq ({3n}/{\Delta (G)+1})$ for any connected graph $G$ with $n\geq 2$ vertices. As examples, we also determine the exact values of the double Roman domination numbers of the generalized Petersen graphs $P(n,1)$ and the double generalized Petersen graphs $DP(n,1)$ . The obtained results imply that $P(n,1)$ is double Roman if and only if $n \not \equiv 2$ (mod 4) and $DP(n,1)$ is double Roman if and only if $n \equiv 0$ (mod 4).

An outer-independent total dominating set (OITDS) of a graph $G$ is a set $D$ of vertices of $G$ such that every vertex of $G$ has a neighbor in $D$ , and the set $V(G)\setminus D$ is independent. The outer-independent total domination number of a graph $G$ , denoted by $\gamma _{oit}(G)$ , is the minimum cardinality of an OITDS of $G$ . An outer-independent total Roman dominating function (OITRDF) on a graph $G$ is a function $f: V(G) \rightarrow \{0, 1, 2\}$ satisfying the conditions that every vertex $u$ with $f(u)=0$ is adjacent to at least one vertex $v$ with $f(v)=2$ , every vertex $x$ with $f(x)\geq 1$ is adjacent to at least one vertex $y$ with $f(y)\geq 1$ , and any two different vertices $a,b$ with $f(a)=f(b)=0$ are not adjacent. The minimum weight $\omega (f) =\sum _{v\in V(G)}f(v)$ of any OITRDF $f$ for $G$ is the outer-independent total Roman domination number of $G$ , denoted by $\gamma _{oitR}(G)$ . A graph $G$ is called an outer-independent total Roman graph (OIT-Roman graph) if $\gamma _{oitR}(G)=2\gamma _{oit}(G)$ . In this paper, we propose dynamic programming algorithms to compute the outer-independent total domination number and the outer-independent total Roman domination number of a tree, respectively. Moreover, we characterize all OIT-Roman graphs and give a linear time algorithm for recognizing an OIT-Roman graph.

This paper investigates horizontal crossover (HC) and stability-based adaptive inertia weight (SAIW) strategies for comprehensive learning particle swarm optimization. HC applies arithmetic crossover on all the dimensions of two different personal best positions. SAIW adaptively adjusts the inertia weight and acceleration coefficient for each particle on each dimension. Experimental results on various benchmark functions demonstrate that HC can significantly improve the convergence performance for the optimizer, while SAIW cannot. The results also indicate that HC and SAIW need to be further improved.

In this paper the electron transport characteristic of GaN photocathode is simulated. After the electrons got across the band bind region and reached to the cathode surface, the distributing of electron energy is 2.3∼3.4 eV. And the surface electron escapes probability of GaN photocathode with different energy is changing with the structure of surface barrier. The barrier I is more impotent that affecting the surface electron escapes probability than that of barrier II, its structure is determined the electron transport characteristic. And in the vacuum, the electron energy that corresponding to the peak electrons number is 2.95 eV.

Analyzing chromatic number in coloring problem is a tough topic in graph analysis. We focus on the basic theory for a particular type of chromatic number. This will give us insights on the basic topological structure guiding lots of networks in the coming trend of big data era. An adjacent vertex-distinguishing total k-coloring is a proper total k-coloring of a graph G such that for any two adjacent vertices, the set of colors appearing on the vertex and its incident edges are different. The smallest k for which such a coloring of G exists is called the adjacent vertex-distinguishing total chromatic number, and denoted by ?at(G). It has been proved that if the graph G satisfies ?(G)=3, then ?at(G)= 6. However, it is very difficult to determine whether ?at(G)= 5. In this paper, we focus on a special class of 3-regular graphs, the generalized Petersen graphs P(n, k), and show that ?at(P(n, k)) = 5, which improves the bound ?at (P(n, k))= 6.

As an important part of requirement management, managing requirement change plays a key role in controlling project schedule and costs at early stage. Effective requirement impact analysis would give proper assessment on the effect of certain requirement changes on the whole system, and provide useful information for making trade-off decisions on future system design and implementation. In this paper a quantitative approach to concern impact analysis at requirement level has been proposed with the application of PageRank algorithm, which is a successful link based web page sorting algorithm. At first, separation of concerns is applied during deriving formal requirement specification from textual requirement statements. Next, concerns are specified and concern relationship graph is established. Finally, PageRank algorithm is utilized on concern relationship graph for assessing the impact of concern changes. Our approach has been applied to hallway section in Light Control System and validation of analysis result has been stated.

Pervasive computing is providing its usability and scope in almost every aspect nowadays. In order to make better use of pervasive services in nomadic devices, pervasive client download might be needed, which would result in serious security problems due to executing untrusted applications. Recently Security-by-Contract has been proposed to address this problem, where an application is required to come with the contract containing a description of the relevant security features while mobile platform will match the contract with its own policy. In this paper a compositional approach to specifying security contract is introduced in the form of extended context free grammar. Then a framework for automatic generation and enforcement of security contract has been presented for Java platform. The main contributions of this paper include: (1) formal definition of security contract is given in the terms of security related operations and the relationship among arguments of these operation; (2) static analysis is utilized to automatically generate security contract for Java source program. The security contract of a Java program can be composed from those of all the methods it invokes; (3) runtime enforcement has been applied to security contracts and achieved by implementing execution monitor in JVM.