Modified Particle Swarm Optimization using Nonlinear Decreased Inertia Weight

Particle Swarm Optimization (PSO) has demonstrated great performance in various optimization problems. However, PSO has weaknesses, namely premature convergence and easy to get stuck or fall into local optima for complex multimodal problems. One of the causes of these weaknesses is unbalance between exploration and exploitation ability in PSO. This paper proposes a Modified Particle Swarm Optimization (MPSO) using nonlinearly decreased inertia weight called MPSO-NDW to improve the balance. The key idea of the proposed method is to control the period and decreasing rate of exploration-exploitation ability. The investigation with three famous benchmark functions shows that the accuracy, success rate, and convergence speed of the proposed MPSO-NDW is better than the common used PSO with linearly decreased inertia weight or called PSO-LDWKeywords: particle swarm optimization (PSO), premature convergence, local optima, exploration ability, exploitation ability

PID Controller Design of Nonlinear System using a New Modified Particle Swarm Optimization with Time-Varying Constriction Coefficient

The proportional integral derivative (PID) controllers have been widely used in most process control systems for a long time. However, it is a very important problem how to choose PID parameters, because these parameters give a great influence on the control performance. Especially, it is difficult to tune these parameters for nonlinear systems. In this paper, a new modified particle swarm optimization (PSO) is presented to search for optimal PID parameters for such system. The proposed algorithm is to modify constriction coefficient which is nonlinearly decreased time-varying for improving the final accuracy and the convergence speed of PSO. To validate the control performance of the proposed method, a typical nonlinear system control, a continuous stirred tank reactor (CSTR) process, is illustrated. The results testify that a new modified PSO algorithm can perform well in the nonlinear PID control system design in term of lesser overshoot, rise-time, settling-time, IAE and ISE.Keywords: PID controller, Particle Swarm Optimization (PSO),constriction factor, nonlinear system

A numeric reading system for digital meter without I/O interface

Recently, measuring instruments that automatically record measurement values by using the communication function of PC and RS232C have been widely used. However, there are a lot of measuring instruments that cannot communicate with an external instrument at present. Also, the ones that have the communication function are very expensive. The system that reads the instruction value from the image is by taking a picture of the measuring instrument with a camera. However, because the specification of the target measuring instrument has been limited, versatility of this system is low. Therefore, this paper proposes a strong numerical recognition system that doesn\u27t depend on the model of a digital measuring instrument. The experiments showed that the proposed method has the characteristics of fast speed, efficiency and strong anti-interference

Pilot VLBI Survey of SiO v=3 J=1--0 Maser Emission around Evolved Stars

In this Letter, we report detections of SiO v=3 J=1--0 maser emission in very long baseline interferometric (VLBI) observations towards 4 out of 12 long-period variable stars: WX Psc, R Leo, W Hya, and T Cep. The detections towards WX Psc and T Cep are new ones. We also present successful astrometric observations of SiO v=2 and v=3 J=1--0 maser emissions associated with two stars: WX Psc and W Hya and their position-reference continuum sources: J010746.0+131205 and J135146.8-291218 with the VLBI Exploration of Radio Astrometry (VERA). The relative coordinates of the position-reference continuum source and SiO v=3 maser spots were measured with respect to those of an SiO v=2 maser spot adopted as fringe-phase reference. Thus the faint continuum sources were inversely phase-referenced to the bright maser sources. It implies possible registration of multiple SiO maser line maps onto a common coordinate system with 10 microarcsecond-level accuracy.Comment: 5 Pages, 3 figures, Fig.3 and Tab. 2 were corrected; Publications of the Astronomical Society of Japan, Vol. 64, No. 6 issued on 2012 December 2

Alternative Starting Position for CT Coronary Angiography

We examined whether the superior margin of the left main bronchus is the best landmark for the starting position of computed tomography coronary angiography（CTCA）. We retrospectively evaluated 693 consecutive CTCAs. From the scout scanogram, the superior margin of the left main bronchus was noted. The relationships among and distance between the superior margin of the left main bronchus and the left coronary system were analyzed. The superior margin of the left main bronchus extended caudally to the superior margin of the left coronary system in 13 patients（1.9％）. The addition of 1cm to the superior margin of the left main bronchus kept it caudal to the superior margin of the left coronary system in only one patient（0.1％）. On the scout scanogram, 1cm above the superior margin of the left main bronchus is the most appropriate starting position for CTCA

Ultrafast charge–discharge characteristics of a nanosized core–shell structured LiFePO4 material for hybrid supercapacitor applications

Highly dispersed crystalline/amorphous LiFePO4 (LFP) nanoparticles encapsulated within hollow-structured graphitic carbon were synthesized using an in situ ultracentrifugation process. Ultracentrifugation triggered an in situ sol–gel reaction that led to the formation of core–shell LFP simultaneously hybridized with fractured graphitic carbon. The structure has double cores that contain a crystalline LFP (core 1) covered by an amorphous LFP containing Fe3+ defects (core 2), which are encapsulated by graphitic carbon (shell). These core–shell LFP nanocomposites show improved Li+ diffusivity thanks to the presence of an amorphous LFP phase. This material enables ultrafast discharge rates (60 mA h g-1 at 100C and 36 mA h g-1 at 300C) as well as ultrafast charge rates (60 mA h g-1 at 100C and 36 mA h g-1 at 300C). The synthesized core–shell nanocomposites overcome the inherent one-dimensional diffusion limitation in LFP and yet deliver/store high electrochemical capacity in both ways symmetrically up to 480C. Such a high rate symmetric capacity for both charge and discharge has never been reported so far for LFP cathode materials. This offers new opportunities for designing high-energy and high-power hybrid supercapacitors

Serum heat shock protein 47 levels are elevated in acute interstitial pneumonia

Background: Heat shock protein (HSP) 47, a collagen-specific molecular chaperone, is involved in the processing and/or secretion of procollagen. We hypothesized that HSP47 could be a useful marker for fibrotic lung disease. The aim of this study was to evaluate serum levels of HSP47 in patients with various idiopathic interstitial pneumonias (IIPs).Methods: Subjects comprised 9 patients with acute interstitial pneumonia (AIP), 12 with cryptogenic organizing pneumonia (COP), 16 with nonspecific interstitial pneumonia (NSIP), 19 with idiopathic pulmonary fibrosis (IPF), and 19 healthy adult volunteers.Results: Patients with AIP had serum HSP47 levels that were significantly higher than those of COP, NSIP or IPF patients and those of healthy volunteers. In contrast, serum levels of HSP47 among patients with COP, NSIP, IPF, and healthy volunteers did not differ significantly. Receiver operating characteristic curves revealed that the cut-off level for HSP47 that resulted in the highest diagnostic accuracy for discriminating between AIP and COP, NSIP, IPF, and healthy controls was 859.3 pg/mL. The sensitivity, specificity, and diagnostic accuracy were 100.0%, 98.5%, and 98.7%, respectively.Conclusion: The present results demonstrate that, among patients with various IIPs, serum levels of HSP47 were elevated specifically in patients with AIP

Comparison of Pulmonary Involvement Between Patients Expressing Anti-PL-7 and Anti-Jo-1 Antibodies

Anti-PL-7 is an anti-tRNA synthetase antibody, and interstitial lung disease (ILD) is the most frequent complication of anti-PL-7-associated antisynthetase syndrome. However, the features of ILD have not been fully elucidated. The present study retrospectively compares 7 and 15 patients who were positive for anti-PL-7 and anti-Jo-1 antibodies, respectively. The features of ILD did not significantly differ between the two groups, but the ratio of lymphocytes in bronchoalveolar lavage fluid was higher in the Jo-1 than in the PL-7 group. High-resolution computed tomography revealed nonspecific interstitial pneumonia in all patients in the PL-7 group and organizing pneumonia in four of the 15 patients in the Jo-1 group. These findings suggest that pulmonary complications slightly differ between patients expressing anti-PL-7 and anti-Jo-1 antibodies. Further studies are required to clarify the features of ILD associated with PL-7