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Motif recognition plays a significant role for understanding the biological meanings of sequences. In this paper, a particle swarm optimization and random projection based algorithm (PSORPS) is proposed for recognizing DNA motifs. First, noise subsequences are filtered by a random projection strategy for constructing objective space. Then the PSO is used to automatically search the motifs of DNA sequences...
In this paper, because of infinite-dimensional feature and complex nonlinearities of the distributed parameter systems, a new data-driven modeling method has been proposed. The temporal-spatial output of the system is measured at a finite number of spatial locations. At the same time it is assumed that the input of the system is a temporal variable. Firstly, Karhunen-Loève(KL) decomposition is used...
The exponentially increasing number of Internet of things (IoT) devices introduces spectrum crisis to the widely used industrial, scientific, and medical (ISM) frequency band. Since IoT devices use heterogeneous radios with different bandwidths (e.g., 20 MHz for WiFi and 2 MHz for ZigBee), traditional interference avoidance methods, such as time-division multiple access (TDMA) and carrier-sense multiple...
Structural reliability issues attract more and more attentions with the rapid development of electronic packaging industry. Sn-Ag-Cu alloys have long been used as solder materials for the interconnections of microelectronic devices because of low melting temperature and good wettability. Many tensile tests were performed on Sn-3Ag-0.5Cu solder alloys at various strain rates and over a wide temperature...
In the current study, the effects of deep cryogenic treatment (DCT) on the microstructure and mechanical properties of Sn-3.0Ag-0.5Cu (SAC30) solder joints were investigated. the mechanism of microstructure, tensile strength and fracture path were discussed. The samples were placed in liquid nitrogen environment at 77 K for 24, 72, 168, and 600 hours. The experimental results show that the strength...
The lead-free solders are adopted to avoid lead pollution in the past decades, however, the mechanical behaviors under complex loading are still requires further study. For example, change of environment temperature is one of the hazards affecting the electronics reliability, especially the temperature cycles which will increase the temperature damage rapidly and the working life could be reduced...
In the current research, a small strain multi-scale constitutive model based on self-consistent method is developed to describe the rate- and temperature-dependent behavior of cyclic deformed Sn-0.7Cu solder. A modification is proposed on the traditional elastic plastic self-consistent (EPSC) model to capture the elasto-viscoplastic behavior of Sn-0.7Cu solder. A modified Voce hardening law is proposed...
Thermal aging effects on the fatigue life of Sn-3.0Ag-0.5Cu (wt%, SAC305) solder joint are investigated. Two series of experiments were conducted: 1) at different temperatures after aging for 72 hours; 2) with different aging time at the cryogenic temperature. The fatigue life of SAC305 solder joint were analyzed statistically by using a modified Weibull distribution model, which takes the thermal...
In the current study, the size effect of Sn3.0Ag0.5Cu solder joints on intermetallic growth is investigated. Experiments were performed to solder joints with a diameter of 2 mm and the solder thickness ranges from 2 mm to 50 µm. The thickness of intermetallic compound (IMC) of solder joints with different thickness as reflowed are found to be dependent on the size of solder joints. The IMC of small...
Thermal cycling is typical working environment of electronic chips due to electronic equipment power on-offs and thermal excursions. Accelerated thermal cycling is widely employed to strictly examine the electronic products for aerospace usage to simulate the actual thermal environment throughout the service life. In this study, the effect of thermal cycling to mechanical property of Sn-3.0Ag-0.5Cu...
This study establishes a new absolute PCV field measurement method according to synchronized dual antenna theory. The new method is relatively simple compared with traditional PCV measurements and takes comprehensive errors source into consideration. Focusing on this new model, this paper carries out several experiments to verify the validity and accuracy of this method. The accuracy of average baseline...
A passive evanescent mode half-mode substrate integrated waveguide (HMSIW) resonator loaded with a complementary split ring resonator (CSRR) is designed and fabricated for humidity sensing applications. The use of the CSRR which is etched on the top plane of the HMSIW can significantly reduce the size of the device. Without any sensing material, the sensor which has a compact size of 5.8 mm×5.8 mm...
For MIMO nonlinear differential-algebraic equations (DAE) subsystem, the Backstepping stabilization control method is studied and the results are applied to the decentralized control of power system. The concept of vector relative order for MIMO nonlinear DAE subsystem is put forward. If the vector relative order exists, then the subsystem can be transformed equivalently by a diffeomorphism and a...
In this paper, we investigate fundamental throughput and delay tradeoffs in cognitive radio networks (CRN) with a primary user (PU) and a cooperative secondary user (SU). Considering the user fairness, we propose a novel cooperation scheme, where the PU transmits packets with a probability of α instead of always occupying the spectrum, in exchange for the SU's cooperation. The unauthorized SU can...
In this paper, we use a bio-inspired robotic simulation framework that mimics the nested architecture of the biological evolutionary process to study biological complexity. Through simulating interactions between different components at different levels, this framework mimics the hierarchical complexity that we observe in biological evolution. Furthermore, by analyzing the results of simulation experiments,...
The exponentially increasing number of IoT devices makes the unlicensed industrial, scientific, and medical (ISM) radio bands (e.g., 2.4 GHz) extremely crowded. Currently, there is no efficient solution to coordinate the large amount heterogeneous IoT devices that have different communication technologies (e.g., WiFi and ZigBee). To fill this gap, in this paper, we introduce embedded multiple flows...
In this paper, a novel 1700V recessed emitter trench IGBT (RET-IGBT) is proposed. The RET-IGBT features an additional recessed trench between two adjacent active trenches and under the emitter contact, which reduces the drawn trench to trench separation from 6μm to 2μm. Combined with a double-dose carrier storage (CS) layers, the injection enhancement effect is enhanced. As a result, the trade-off...
The research and development of dual-arm robot is a new direction of the robot industry development. Relative to the single arm robot, it not only can greatly enhance the adaptability for complex work, but also can improve the efficiency of work space [1]. In this paper, the kinematics equation of the end of the arm is deduced using the D-H method. Then the control algorithm based on the state space...
Digital Array Module (DAM) is one of the key components of digital array radar (DAR). Usually, a DAR contains tens to hundreds of DAMs, which is making it increasingly difficult for human operators to test them in limited time. Therefore, the technique for automatic test of DAMs is in urgent demand. This paper presents a DAM automatic test system (ATS) that has proved successful in several radar test...
Image annotation is a hard multi-label learning problem which aims at automatically tagging each input image with relevant keywords reflecting its semantic concepts. Recently, several late fusion methods were proposed to improve the accuracy of image annotation. But these late fusion methods need normalization of confidence score vectors of independent models corresponding to distinct representations...
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