Search

Combining distributed model predictive control (DMPC) with the terminal invariant set, this paper designs a distributed control scheme for multiple unmanned ground vehicles (UGVs) formation. When unexpected situation such as road construction occurs, UGVs can change formation to cope with emergency. It is an important issue to accurately estimate the lost data and continue to complete the task when data packet loss occurs in the process of UGVs communication. In order to ensure stability of the controller, the terminal invariant set and the local feedback control law are added at the end of predictive time domain, and then solved by using linear matrix inequalities (LMI). Considering the formation task, collision avoidance constraint, control input constraint and terminal constraint, an optimization model is formed. By solving the optimization model, control input and optimal estimation of future path can be confirmed. Then, the updated path is sent to the adjacent UGVs for collision avoidance. Finally, combining the time window, data estimation based on local feedback control law is discussed when the data packet loss occurs.

Meckel syndrome (MKS) is a pre‐ or perinatal multisystemic ciliopathic lethal disorder with an autosomal recessive mode of inheritance. Meckel syndrome is usually manifested with meningo‐occipital encephalocele, polycystic kidney dysplasia, postaxial polydactyly and hepatobiliary ductal plate malformation. Germline variants in CEP290 cause MKS4. In this study, we investigated a 35‐years‐old Chinese female who was 17+1 weeks pregnant. She had a history of adverse pregnancy of having foetus with multiple malformations. We performed ultrasonography and identified the foetus with occipital meningoencephalocele and enlarged cystic dysplastic kidneys. So, she decided to terminate her pregnancy and further genetic molecular analysis was performed. We identified the aborted foetus without postaxial polydactyly. Histological examination of foetal kidney showed cysts in kidney and thinning of the renal cortex with glomerular atrophy. Whole exome sequencing identified a novel homozygous variant (c.2144T>G; p.L715*) in exon 21 of the CEP290 in the foetus. Sanger sequencing confirmed that both the parents of the foetus were carrying this variant in a heterozygous state. This variant was not identified in two elder sisters of the foetus as well as in the 100 healthy individuals. Western blot analysis showed that this variant leads to the formation of truncated CEP290 protein with the molecular weight of 84 KD compared with the wild‐type CEP290 protein of 290 KD. Hence, it is a loss‐of‐function variant. We also found that the mutant cilium appears longer in length than the wild‐type cilium. Our present study reported the first variant of CEP290 associated with MKS4 in Chinese population.

Vasculogenic mimicry (VM) is an alternative type of blood and nutrition supply that is associated with more aggressive tumor biology and increased cancer-related mortality. However, the clinical implications of VM remain unclear in patients with pancreatic ductal adenocarcinoma (PDAC). The aim of this study was to investigate the clinical significance of VM in PDAC patients and to seek a novel and more efficient treatment strategy by targeting this unique process. Here, cluster of differentiation 34 (CD34)/periodic acid-Schiff (PAS) double-staining of 76 PDAC clinical specimens revealed that VM expression was related to clinical stage (P=0.049) and lymph node metastasis (P=0.023). Notably, VM expression was correlated with a poor prognosis in patients with PDAC. Additionally, we discovered that there was a positive correlation between the expressions of VM and phosphorylated extracellular signal regulated kinase (p-ERK1/2) in 76 clinical samples (P

Chronic Heart Failure (CHF) is a complex clinical syndrome with a high incidence worldwide. Although various types of pharmacological and device therapies are available for CHF, the prognosis is not ideal, for which, the control of increased Heart Rate (HR) is critical. Recently, a bradycardic agent, ivabradine, is found to reduce HR by inhibiting the funny current (If). The underlying mechanism states that ivabradine can enter the Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels and bind to the intracellular side, subsequently inhibiting the If. This phenomenon can prolong the slow spontaneous phase in the diastolic depolarization, and thus, reduce HR. The clinical trials demonstrated the significant effects of the drug on reducing HR and improving the symptoms of CHF with fewer adverse effects. This review primarily introduces the chemical features and pharmacological characteristics of ivabradine and the mechanism of treating CHF. Also, some expected therapeutic effects on different diseases were also concluded. However, ivabradine, as a typical If channel inhibitor, necessitates additional research to verify its pharmacological functions.

In the technology of liquid ammonia modification, the ammonia is recycled by compression and condensation. To minimize the energy-consumption of ammonia recycling system, compression ratio and fan speed are optimized. Thermodynamic models for the compressor and evaporative condenser are developed respectively. Mathematical equations are given to determine the optimal compression ratio and the corresponding fan speed ratio. To solve the equations, a numerical algorithm is proposed. By controlling the fan speed, the matching of ammonia mass flow rate and air flow rate can be optimized, which brings about the minimal energy-consumption. When the wet-bulb temperature is 22 °C, the system energy-consumption could be saved by 10.8–12.9% under optimal compression ratio and fan speed.

Bifurcation and chaos characteristics of single phase power converter in switched reluctance motor (SRM) drive system are studied by establishing its corresponding discrete iterative map model in this article. The discrete iterative map model of the converter is first derived. The stability theoretical analysis shows that the system may lose stability as the variation of system parameters in periodic-1 operation. With the bifurcation diagrams and Lyapunov exponents’ analyses, the operation state regions of current-controlled single phase of SRM drive can shift among stable periodic-1 region, chaos region and multi-periodic region. To verify the theoretical analysis results, time-domain waveforms and power spectra of current-controlled single phase of SRM drive are obtained by Runge–Kutta algorithm. Moreover, theoretical analysis and simulation results are verified by experimental circuit.

Aiming at reducing the energy-consumption of ammonia recycling system, we presented floating condensing temperature control to maximize the coefficient of performance (COP) of the system. Firstly, thermodynamic models for the compressor and evaporative condenser were developed respectively. Then, an evaluation index and a solution scheme were proposed to determine the optimal set point of condensing temperature and the corresponding compressor speed. It is found that the system COP can be maximized by controlling the compressor speed to adjust the set point based on any given operating conditions. When the wet-bulb temperature is 22 °C, the system COP could be improved by 19.2–27.6% under floating condensing temperature control.

Aiming at improving heat utilization of the evaporative condenser in the equipment of flax fiber modification, we proposed a new method to control the main factors that affect the heat exchange of the evaporative condenser. Firstly, a steady-state mathematical model was developed to evaluate the heat exchange of evaporative condenser after analyzing the heat exchange process of ammonia recovery system in the modification equipment and the thermal mass transfer process of evaporative condenser on details. Then, the thermal load of evaporative condenser was computed and analyzed through the numerical simulation. It is found that the suction pressure of compressor has obvious influence on the thermal load of evaporative condenser. Besides, under the maximum suction pressure, the thermal load is 291.4 kW, and the corresponding air speed and spraying water volumetric flow rate are 2.5 m/s and 12 m 3 /h, respectively. When the thermal load decreases, the air speed and spraying water volumetric flow rate are adjusted accordingly.

A novel total synthesis of Mansouramycin B (1) was performed via 10 steps in 28% overall yield starting from the readily available and cheap salicylaldehyde. Two key steps of this total synthesis are noteworthy. The first one is base-promoted one-pot aerobic aromatization of N-tosyltetrahydroisoquinoline 6, the second one is oxidation of 5-hydroxy-3-methyl-isoquinoline 8 with iodobenzene diacetate [PhI(OAc)2].

Solar cell model is used in various studies of photovoltaic system. Different methods have been developed to determine model parameters. In this paper, an optimization technique based on cat swarm optimization (CSO) algorithm is proposed to estimate the unknown parameters of single and double diode models. To investigate the effectiveness of proposed approach, comparative studies with other techniques are presented. The evaluation for the quality of identified parameters is also given. Results demonstrate the high performance of developed approach, high accuracy of estimated parameters, and calculated I–V curve is in good agreement with experimental I–V data. In addition, the sensitivity of performance to control parameter of CSO is also investigated. Results show the proposed CSO algorithm can be an effective tool to solve the optimization problem of parameter identification of solar cell models.

Aiming at the particularity of a multiple-stage closed-loop gear transmission system for 3D circular braiding machine, the model of gear transmission system in radial braiding machine was simplified. The non-linear dynamic equations of a n-elements closed-loop gear transmission system with symmetrical structure including static transmission error, the random disturbance of meshing damping and backlash were considered. For convenience of calculation n = 3, the equations were solved numerically by using Runge-Kutta. The dynamic transmission error(DTE) with different backlash, dynamic meshing forces with and without the random disturbance of meshing damping, the amplitude of dynamic transmission error at n = 1000 r/min and b = 2.65 &times, 10&minus, 5 m, root mean square(RMS) of DTE and the mean value of DTE of the first pair of gears were analyzed. The simulation results show that different backlash and the random disturbance of meshing damping have a great influence on the dynamic displacement error and meshing force of the gear pair, and RMS and the mean value of DTE changes at different rotational speeds. The results will provide a reference for realizing the smoothness of the closed-loop gear transmission system with symmetrical structure for 3D braiding machine and have great practical significance for improving the braiding quality.

A high precision time delay calibration system based on optical fiber switches and fiber coils network for the satellite range measurement system is proposed in this paper. To reach the high time delay precision, the Phase Stabilized Optical Fiber (PSOF), is proposed to use as time delay component instead of the Single Mode Fiber (SMF) to minimize the temperature dependence of transmission delay time. In order to verify the time delay precision, a low coherence interferometry which contains a Michelson interferometer and a Mach-Zehnder interferometer is used to measure the thermal coefficient of delay of the PSOF compared with the SMF from −20 to 60℃. The result showed that by using the PSOF, the temperature error can be decreased by 4.15 times compared with using the standard SMF in the fiber based range measurement system.

The nano-sized zero valent iron assisted biochar from hazelnut shell (nZVI@biochar) was prepared and assessed for the feasibility as the binding agent in diffusive gradients in thin-films (DGT) technique. The 1.5% agarose solution containing the optimal nZVI@biochar dose of 15 g L−1 was used to prepare the nZVI@biochar binding gel which owned a high capacity (1010 ± 50 μg disc−1) and a rapid uptake within 30 min. The elution efficiency of phenol from the loaded binding gel was up to 99.3% using the mixture of 1% hydroxylamine hydrochloride and 0.05 mol L−1 HCl. The phenol uptake of nZVI@biochar-DGT increased linearly with the increase of deployment time (R2 = 0.9938) and was in accord with the theoretical values from DGT equation, while there was no notable interference of the sample matrixes on the phenol uptake of nZVI@biochar-DGT in the spiked freshwaters. The good performance of nZVI@biochar-DGT was found under a range of pH (4.1–10.2), ionic strength (as pNaNO3) (0.155–4), and dissolved organic matter up to 20 mg L−1. In field, the monitoring of nZVI@biochar-DGT was more representative than the results from the grab-sampling with better precision and lower sampling frequency, which can provide reliable information, reduce the cost of human resources, and improve efficiency. These illustrate that the nZVI@biochar is more suitable as the binding agent of DGT for uptake of phenol and nZVI@biochar-DGT is an effective tool to monitor in-situ phenol in waters.

As human cytomegalovirus (HCMV) is a common cause of disease in newborns and transplant recipients, developing an HCMV vaccine is considered a major public health priority. Yet an HCMV vaccine candidate remains elusive. Although the precise HCMV immune correlates of protection are unclear, both humoral and cellular immune responses have been implicated in protection against HCMV infection and disease. Here we describe a vaccine approach based on the well-characterized modified vaccinia virus Ankara (MVA) vector to stimulate robust HCMV humoral and cellular immune responses by an antigen combination composed of the envelope pentamer complex (PC), glycoprotein B (gB), and phosphoprotein 65 (pp65). We show that in mice, multiantigenic MVA vaccine vectors simultaneously expressing all five PC subunits, gB, and pp65 elicit potent complement-independent and complement-dependent HCMV neutralizing antibodies as well as mouse and human MHC-restricted, polyfunctional T cell responses by the individual antigens. In addition, we demonstrate that the PC/gB antigen combination of these multiantigenic MVA vectors can enhance the stimulation of humoral immune responses that mediate in vitro neutralization of different HCMV strains and antibody-dependent cellular cytotoxicity. These results support the use of MVA to develop a multiantigenic vaccine candidate for controlling HCMV infection and disease in different target populations, such as pregnant women and transplant recipients. IMPORTANCE The development of a human cytomegalovirus (HCMV) vaccine to prevent congenital disease and transplantation-related complications is an unmet medical need. While many HCMV vaccine candidates have been developed, partial success in preventing or controlling HCMV infection in women of childbearing age and transplant recipients has been observed with an approach based on envelope glycoprotein B (gB). We introduce a novel vaccine strategy based on the clinically deployable modified vaccinia virus Ankara (MVA) vaccine vector to elicit potent humoral and cellular immune responses by multiple immunodominant HCMV antigens, including gB, phosphoprotein 65, and all five subunits of the pentamer complex. These findings could contribute to development of a multiantigenic vaccine strategy that may afford more protection against HCMV infection and disease than a vaccine approach employing solely gB.

Based on the matrix method and clearance vector model, a simple, accurate, efficient and general mechanical reliability analysis method is presented to analyze the reliability of a complex linkage mechanism with structural errors and clearances. The output error variances of the latch needle mechanism in double-needle warp knitting machine are obtained based on this matrix method and verified by Monte-Carlo method. Then, an optimization design method for the latch needle mechanism is presented with the use of genetic algorithm, considering the motion requirement and output errors. The optimized latch needle mechanism can meet the double-dwell motion requirement, and has higher displacement accuracy and reliability under the same structural errors and clearance conditions. This method has practical engineering value in solving the contradiction between high precision loop-forming motion and multi-link accumulative errors, reducing cost, and providing a reference for the optimization design for loop forming mechanism in a warp knitting machine.

The primer sequences of miR-200c mimic, miR-200c inhibitor, siRNA against MALAT-1, and their respective negative controls. (DOCX 15 kb)

Initial profiling of miRNAs that have base-pairing with MALAT-1 in response to knockdown of MALAT-1. (DOCX 16 kb)

Correlation between the clinicopathologic characteristics and MALAT-1 and miR-200c-3p expression in PDAC (nâ =â 65). (DOCX 21 kb)

Summary of univariate and multivariate COX regression analysis of OS duration in all PDAC patients (nâ =â 65). (DOCX 20 kb)

A green chemical method for the conversion of 3,4-dihydro-β-carbolines to β-carbolines has been developed using air as the oxidant. With 15 mol % CuBr2 as the catalyst, 3,4-dihydro-β-carbolines could be efficiently oxidized to β-carbolines in dimethyl sulfoxide at room temperature in the presence of 1,8-diazabicyclo[5,4,0]undec-7-ene (or Et3N). By applying this method, the first total synthesis of 6-hydroxymetatacarboline D was performed through 12 steps in 22% overall yield starting from l-5-hydroxy-tryptophan.

A FLC has the characteristics of the distributed, scalable and flexible structure.The FLC is scaled by fuzzy accuracy factor in terms of fuzzy system elements.Scalable FLC reduces the complexity of design, speeds up fuzzy logic operation. A distributed, scalable and flexible fuzzy logic controller (FLC) without increasing additional hardware cost by fuzzy accuracy factor is proposed. In order to improve fuzzy logic operation speed, multi-input/multi-output (MIMO) fuzzy system is decomposed into several independent two-input/single-output (TISO) subsystems in parallel. The decomposed TISO FLC can deal with scalable requirements in terms of number of input language variables, output language variables, data accuracy types and fuzzy rules. In this paper, the systematic design methods are presented in detail, and the scalable TISO FLC architectures are addressed with fuzzification of fuzzy accuracy factor and analog-to-digital conversion (ADC) quantizer, fuzzy rules and fuzzy inference engine, and the defuzzification by a scalable divider. At last, A JTAG-TCL tool is developed to compare the scalable TISO FLC with other FLCs in resource, accuracy, and speed. The experiment results of photovoltaic (PV) system indicate that the proposed FLC has flexible control accuracy, fast response and better tracking performance.

A chaotic neural network model with logistic mapping is proposed to improve the performance of the conventional diagonal recurrent neural network. The network shows rich dynamic behaviors that contribute to escaping from a local minimum to reach the global minimum easily. Then, a simple parameter modulated chaos controller is adopted to enhance convergence speed of the network. Furthermore, an adaptive learning algorithm with the robust adaptive dead zone vector is designed to improve the generalization performance of the network, and weights convergence for the network with the adaptive dead zone vectors is proved in the sense of Lyapunov functions. Finally, the numerical simulation is carried out to demonstrate the correctness of the theory.

This paper first presents a 3-D analysis model for calculating the torque transmitted between the permanent radial magnet couplers based on the Coulombian model. Then, a 3-D finite-element analysis model is constructed to analyze the spatial distributions of the magnetic field and end effect of the axial length of the magnet coupler. Besides, the parametric studies of the magnet coupler are taken using the two 3-D models, respectively, and the simulation results obtained are analyzed and compared. Finally, two kinds of real applied magnet couplers are tested to compare with the results with the 3-D analysis model. It is concluded that the 3-D analytical model of the torque of the radial magnet couplers is viable and could be used for the design of magnet couplers.

The objective is to explore the feasibility of ultrasound technology for quantitative analysis of wool in blended fabrics with chemical dissolution. Two varieties of mixture fabric with wool content of 45.1 and 16.7% were employed and were dissolved in solution of sodium hypochlorite with ultrasound assistance at different frequencies of 20, 28 and 40 kHz. By statistical method, the data for both blends indicated that there were no significant difference among the three ultrasound frequencies when applied to textile quantitative chemical analysis. For evaluation of ultrasound reliability, two insoluble materials were dissolved in sodium hypochlorite. Relative errors showed that ultrasound has little impact on the quality of insoluble fibers as well as mechanical stirring. Compared with mechanical agitation, wool was dissolved completely in a short time and at low liquor ratio when assisted with ultrasound. The results suggested that it was feasible to quantitatively analyze the wool in blended fabrics wit...

We report the first study of using optical coherence tomography (OCT) to inspect the winding quality of fiber optical gyro coils. We use a swept-source OCT system to scan a quadrupole-wind fiber coil for obtaining its two-dimensional and three-dimensional (3D) tomographic images. The defects beneath the surface of the fiber coil, which otherwise are invisible by video inspection, can be clearly identified with such tomographic images. The winding quality of each layer can also be independently visualized with the reconstructed 3D images from different angles or in different sections. We believe that the proposed method will be useful to ensuring the quality production of each and every fiber gyro coil.

We present methods and processes of using a ghost-peak-free distributed polarization crosstalk analyzer (DPXA) to accurately obtain all polarization related parameters of polarization-maintaining (PM) fibers. We show that by first inducing a series equidistant periodic polarization crosstalk peaks along a PM fiber and then measuring the positions and the widths of these peaks using the analyzer, all birefringence related parameters of the PM fiber, including group birefringence, group birefringence variation along the fiber, group birefringence dispersion, and group birefringence temperature coefficient , can be accurately obtained. We further show that the DPXA has the ability to identify and eliminate polarization crosstalk contributions of connectors or splices in the measurement system and therefore can be used to obtain high accuracy measurement of the polarization extinction ratio (PER) of PM fibers. Finally, we propose a set of parameters based on the distributed polarization analysis to quantitatively evaluate the quality of PM fibers. We believe that the methods and processes described in this paper can be widely applied in the industry for the complete characterization of PM optical fibers.

A new technology of lattice distortion modification of cotton/linen fiber and yarn is introduced in this paper. The process parameters and control requirements in the lattice distortion modification processing are analyzed for designing its control system, The hardware system is designed using the Omron PLC as control core and the human-computer interaction interface is built by using configuration software. At last, a real time accurate program on fuzzy compensated decoupling control of the temperature and pressure in the modification process is presented. The test production results show that the control system designed totally meets the production requirements of the lattice distortion modification of cotton/linen fiber and yarn.

In order to meet the technical production requirements of the ammonia modification equipment, this paper develops a set of electrical control system based on Omron CJ2M Series PLC, including the configuration of the hardware and software, the assignment of the input/output, and the design of communication system. The control system provides a perfect human-machine interaction and realizes the automation control of the devices.Through actual application, this control system can meet the control requirements of the ammonia modification production and raise the production automation level of the factory and increase labor productivity.

As human cytomegalovirus (HCMV) is the most common infectious cause of fetal anomalies during pregnancy, development of a vaccine that prevents HCMV infection is considered a global health priority. Although HCMV immune correlates of protection are only poorly defined, neutralizing antibodies (NAb) targeting the envelope pentamer complex (PC) composed of the subunits gH, gL, UL128, UL130, and UL131A are thought to contribute to the prevention of HCMV infection. Here, we describe a continuous target sequence within UL128 that is recognized by a previously isolated potent PC-specific NAb termed 13B5. By using peptide-based scanning procedures, we identified a 13-amino-acid-long target sequence at the UL128 C terminus that binds the 13B5 antibody with an affinity similar to that of the purified PC. In addition, the 13B5 binding site is universally conserved in HCMV, contains a previously described UL128/gL interaction site, and interferes with the 13B5 neutralizing function, indicating that the 13B5 epitope sequence is located within the PC at a site of critical importance for HCMV neutralization. Vaccination of mice with peptides containing the 13B5 target sequence resulted in the robust stimulation of binding antibodies and, in a subset of immunized animals, in the induction of detectable NAb, supporting that the identified 13B5 target sequence constitutes a PC-specific neutralizing epitope. These findings provide evidence for the discovery of a continuous neutralizing epitope within the UL128 subunit of the PC that could be an important target of humoral immune responses that are involved in protection against congenital HCMV infection. IMPORTANCE Neutralizing antibodies (NAb) targeting the human cytomegalovirus (HCMV) envelope pentamer complex (PC) are thought to be important for preventing HCMV transmission from the mother to the fetus, thereby mitigating severe developmental disabilities in newborns. However, the epitope sequences within the PC that are recognized by these potentially protective antibody responses are only poorly defined. Here, we provide evidence for the existence of a highly conserved, continuous, PC-specific epitope sequence that appears to be located within the PC at a subunit interaction site of critical importance for HCMV neutralization. These discoveries provide insights into a continuous PC-specific neutralizing epitope, which could be an important target for a vaccine formulation to interfere with congenital HCMV infection.

Clinical description of cancer patients. Table S2. Statistics of whole-genome sequencing results. Table S3. SNVs and indels that called by GATK and passed the quality control. (DOCX 90Â kb)

This paper provides a method of multi-sensor data detection and fusion, aims to resolve the data measurement inaccurate problem in the process variable control system of the ammonia modification equipment. First, it establishes the sensor data measurement model and calculates mutual support level of the multiple sensors, using boundary value judgment method to produce the multiple-sensor mutual support level matrix, the total number of mutual support level for one sensor in the matrix is the weight value of this sensor, and finally the normalized weighted average data fusion (NWADF) method is used for data process.Experimental results show that the proposed method for multi-sensor data fusion can effectively be used to identify the abnormal data in multi-sensor measurement system and improve the accuracy and stability of the process variable data measurement.

We examined the antineoplastic effects of the iron chelators, deferasirox and deferoxamine in multiple myeloma cell lines as well as primary myeloma cells. These iron chelators showed marked antiproliferative activity as well as cytotoxicity toward myeloma cell lines and deferasirox was cytotoxic to bone marrow plasma cells from myeloma patients. We also demonstrate that autophagy induced by iron deprivation is the dominant mechanism that mediates the cytotoxicity of iron chelators in multiple myeloma. Exposure to iron chelators led to repression of mTOR signaling as evidenced by decreased phosphorylation of its target p70S6 kinase. Iron chelation, in particular with deferasirox has the potential to be readily translated to a clinical trial for multiple myeloma.

In this paper, a comprehensive modeling and parameters extraction method is proposed to describe the current–voltage and power–voltage characteristic of photovoltaic cells. This method is based on data commonly issued by commercial photovoltaic data sheet. By using Lambert W function, the improved model of solar cells is given. Meanwhile, the current–voltage and power–voltage curves of photovoltaic cells are calculated. To extract the model parameters from only three state points at standard test conditions, an optimized approach using iterative method and approximate method is presented. Compared to the popular R p model and experimental data, the proposed method shows excellent agreement between the current–voltages points. It is found that the proposed modeling and parameters extraction method has less error at the maximum power point state. Moreover, the proposed model is more realistic when subjected to ideality factors variations.

Noninvasive glucose monitoring (NIGM) techniques based on optical coherence tomography (OCT) are affected by several perturbing factors, including variation of tissue temperature. We first design a temperature control module integrated with an optical scanning probe to precisely control the temperature of skin tissues. We investigate the influence of temperature on NIGM with OCT by correlation analysis at different depths of in vivo human skin. On average, the relative changes in attenuation coefficient (µt) per 1 °C of temperature lead to 0.30 ± 0.097 mmol/L prediction error of blood glucose concentration. For NIGM measurement methods using optical properties of the tissues, this effect can be taken into account.

Carbon fiber braids are widely applied in various industrial fields as structural components. However, using braiding machines to braid carbon fibers is an emerging technology, but some technical problems must be solved. For instance, carbon fibers are easily fluffed when using traditional carriers; with increasing braiding speed, the machine fiercely vibrates. To investigate these problems, an improved mechanical structure of the carrier is designed, which reduces the friction between the carbon fiber and guide hole and changes the carbon fiber storage quantity. Based on the carrier, the corresponding mathematical model of the tensioning system is established by the dynamical equations, and numerical analyses and simulations are carried out. Moreover, the validation of the established mathematical model is verified. According to the results of the simulation, the fluctuation in the tensioning force is smaller than that in previous studies, and the trend is in accordance with previous research results. As a result, the present model provides a better description of the dynamic process of carbon fiber braiding.

The type of Solar panels in photovoltaic power generating system is generally photovoltaic array. On the basis of the photovoltaic array mathematical model for engineering , using the mathematical software MATLAB Simulink tool to build a photovoltaic array simulation model and utilizing monitoring data acquired by the detection system-Sunny Sensor Box-for Donghua University photovoltaic power generating system, the mathematical model of the PV array for engineering is optimized and the optimization includes linear and natural exponential optimization. Furthermore, higher accuracy of the optimized models is validated.

In this paper, an improved model of photovoltaic cell is proposed. By using Lambert W function, the improved model of solar cell is deduced. Meanwhile, the current-voltage and power-voltage curves of photovoltaic cell are calculated and simulated in Matlab/Simulink environment. Compared to the popular model and experimental data, the proposed method shows excellent agreement between the current-voltage points. It is found that the proposed modeling method has less error at the maximum power point state.

An efficient and general method for the highly stereoselective transformation of (1 S ,3 S )- cis -1,3-disubstituted 1,2,3,4-tetrahydro-β-carbolines (THBCs) into (1 S ,3 R )- trans -1,3-disubstituted THBCs is described. The method contains the following three steps: the enantiomerically pure (1 S ,3 S )- cis -1,3-disubstituted THBCs 1 were first converted into (1 S ,3 S )- cis -1,2,3-trisubstituted THBCs 2 by N-1-naphthylmethylation/benzylation; (1 S ,3 S )- cis -1,2,3-trisubstituted THBCs 2 were then converted into (1 S ,3 R )- trans -1,2,3-trisubstituted THBCs 3 in high yields and with high stereoselectivities via a base-catalyzed epimerization at C-3; (1 S ,3 R )- trans -1,2,3-trisubstituted THBCs 3 were subsequently converted into (1 S ,3 R )- trans -1,3-disubstituted THBCs 4 after reductive removal of the 1-naphthylmethyl/benzyl group. In addition, as an application of this method, an improved and highly stereoselective synthesis of the PDE5 inhibitor tadalafil (Cialis®) starting from natural and less expensive l -tryptophan was developed.

A polyurethane based on unsaturated polyesters (PUP) was prepared, which can be cured and cross-linking reaction under room temperature. The polyurethane-based resin exhibited excellent endurance to acid and base relative to traditional unsaturated polyester resin. Different content and particle size of aluminum hydroxide particles were added into the PUP to improve the properties of final materials. Experiment results showed that proper content and size of aluminum hydroxide particles can improve the mechanic properties, thermal stability and electrical insulation of PUP materials to some extent. Such result was confirmed by the fracture morphology of the samples because of the well dispersion of aluminum hydroxide particles into PUP phase.

Tufted carpet is one of the most used carpets. The penetration force of needle is an important factor in tufting process. Few know how to calculate the penetration force during the tufting, although the principle is one of the least understood processes. This paper presents our research on using finite element method (FEM) to study the penetration force of needle during tufting. In this study, the model is developed using ABAQUS software, and the material properties of nonwoven fabric are approximately modeled by linear elastic orthogonal anisotropic continuum. The required engineering constants were obtained from experimental test. A user-defined subroutine VUMAT for characterizing the constitutive relationship of the orthogonal anisotropy nonwoven fabric and the damage evolution was compiled and connected with a commercial software package ABAQUS/Explicit to calculate the penetration force. At the same time, needle penetration force was tested by sensor mounted on needle bar of tufting machine. It was f...

A new method is proposed to describe the characteristics of solar cell and module in this article. By using the exact explicit analytical solutions, the current–voltage and power–voltage curves of the corresponding modules are calculated and simulated. In order to extract the parameters of the solar cells, an optimized technique is presented by using Lambert W function and polynomial curve fitting. The accuracy of the model is compared with previous methods in other work. Results have the good agreement between the fitted current–voltage curves and the experimental data. Moreover, error and statistical analyses are carried out to illustrate the accuracy of the estimated parameters and procedure suitability.

We present a novel method to significantly extend the measurement range of an optical frequency domain reflectometry (OFDR) beyond the laser coherence length for both discrete reflection (such as Fresnel reflection) and Rayleigh backscattering measurements. A key to the method is to increase the laser frequency tuning speed while measuring the phase noise of the reflected optical signal that carries the location and reflectivity information. Using this technique in a conventional OFDR with a noise floor of -120ndB and a dynamic range of 53 dB, we achieved a measurable distance of 170 km for Fresnel reflection and 120 km for Rayleigh backscattering using a laser with a coherence length of only 13.6 km.

This paper first presents a 3D analytical model for analyzing the radial air-gap magnetic field between the inner and outer magnetic rotors of the permanent magnet couplings by using the Amperian current model. Based on the air-gap field analysis, the eddy current loss in the isolation cover is predicted according to the Maxwell’s equations. A 3D finite element analysis model is constructed to analyze the magnetic field spatial distributions and vector eddy currents, and then the simulation results obtained are analyzed and compared with the analytical method. Finally, the current losses of two types of practical magnet couplings are measured in the experiment to compare with the theoretical results. It is concluded that the 3D analytical method of eddy current loss in the magnet coupling is viable and could be used for the eddy current loss prediction of magnet couplings.