Search

The main objective of the study was to evaluate the bioequivalence of two rosuvastatin calcium tablets in healthy Chinese subjects under fasted and fed conditions. The study was carried out using a randomized, open-label, two-formulation, two-sequence, two-period, single-dose crossover design, with a washout period of 7 days. Both the fasted study and fed study enrolled 28 subjects. In each study period, the subjects were administrated a single oral dose of the test product or reference product of rosuvastatin 10 mg. Blood samples were collected from pre-dose to 72 hours after administration with 16 time points in total. Bioequivalence evaluation was performed using ln-transformed pharmacokinetic parameters of rosuvastatin, including C

OBJECTIVE The study mainly aimed to determine the bioequivalence of two branded ciprofloxacin hydrochloride tablets (250 mg) under fasting and fed conditions. MATERIALS AND METHODS The study was carried out in 48 healthy Chinese subjects under fasting and fed conditions with a randomized, open-label, two-formulation, two-sequence, two-period, single-dose crossover design. In each period of the study, the subjects were assigned to receive a single oral dose of 250 mg ciprofloxacin hydrochloride. Blood samples were collected from 1 hour before dosing to 36 hours after administration with 16 timepoints in total. The bioequivalence analysis was performed after ln-transformation of the ciprofloxacin pharmacokinetic parameters including Cmax, AUC0-t, and AUC0-∞. RESULTS A total of 48 subjects were enrolled in the fasting and fed studies, and 1 of the subjects was excluded before drug administration. In the fasting study, the 90% CIs for the test/reference geometric mean ratios (GMRs) of the ln-transformed data for Cmax, AUC0-t, and AUC0-∞ were 85.41 - 100.97%, 95.40 - 100.27%, and 95.48 - 100.30%, respectively. For the fed study, the 90% CIs for the test/reference GMRs of the ln-transformed data for Cmax, AUC0-t, and AUC0-∞ were 90.15 - 113.75%, 99.10 - 103.77%, and 99.11 - 103.80%, respectively. These values all fell within the standard acceptance range of 80 - 125%. CONCLUSION In the study, the generic (test) product of ciprofloxacin hydrochloride 250 mg was bioequivalent to the innovator (reference) product after single-, oral-dose administration under fasting and fed conditions.

BackgroundCiprofloxacin is a broad-spectrum fluoroquinolone antibiotic which is active against a wide range of Gram-positive and Gram-negative bacteria. The study mainly aimed to determine the bioequivalence of two branded ciprofloxacin hydrochloride tablets (250 mg) under the fasting and fed conditions.MethodsThe study was carried out in 48 healthy Chinese subjects under fasting and fed conditions with a randomized, open-label, two-formulation, two-sequence, two-period, single-dose crossover design. In each period of the study, the subjects were assigned to receive a single oral dose of 250 mg of ciprofloxacin hydrochloride. Blood samples were collected from an hour before dosing to 36 h after administration with 16 time points in total. The bioequivalence analysis was performed after ln-transformation of the ciprofloxacin pharmacokinetic parameters including maximum concentration (Cmax), area under the plasma concentration–time curve from time 0 to time t (AUC0-t), area under the plasma concentration-time curve from time 0 to infinity (AUC0-∞). Two formulations are considered bioequivalent if the 90% confidence intervals (CIs) for the test/reference geometric mean ratios (GMRs) for the ln-transformed pharmacokinetic parameters fall within the standard acceptance range of 80% – 125%. ResultsIn total of 48 subjects were enrolled in the fasting and fed studies, and one of the subjects was excluded before the administration. In the fasting study, the 90% CIs for the test/reference GMRs of the ln-transformed data for Cmax, AUC0–t, and AUC0–∞ were 85.41% to 100.97%, 95.40% to 100.27%, and 95.48% to 100.30%, respectively. For the fed study, the 90% CIs for the test/reference GMRs of the ln-transformed data for Cmax, AUC0–t, and AUC0–∞ were 90.15% to 113.75%, 99.10% to 103.77% and 99.11% to 103.80%, respectively. A total of 8 of 47 subjects experienced AEs in the fasting and fed studies.ConclusionsIn the study, the generic (test) product of ciprofloxacin hydrochloride 250 mg was bioequivalent to the innovator (reference) product after a single oral dose administration under the fasting and fed conditions. Both two brands of ciprofloxacin tablets were safe and well tolerated.Trial registrationThe clinical trial was registered at Center for the Drug Evaluation of the National Medical Products Administration (registration number: CTR20171152; date of registration：September 25, 2017; http://www.chinadrugtrials.org.cn/clinicaltrials.searchlistdetail.dhtml).

With the development of artificial intelligence algorithm, BP neural network algorithm is widely used in many fields, such as fault diagnosis, intelligent control and dynamic signal processing, because it has many advantages for example self-learning, self-organization and nonlinear mapping. Compared with BP neural network, the hidden Markov model is suitable for dynamic time series modeling and has strong temporal classification ability. However, the hidden Markov model has problems of initial model optimization and algorithm underflow when applied to pattern classification. In this paper, the discrete hidden Markov model (DHMM) and BP neural network algorithm are combined to apply to the fault diagnosis of gearbox. Firstly, the probabilities of failures were obtained by preprocessing of the fault samples. Then the probabilities are added to the time-frequency characteristics as new features. The BP neural network algorithm were used to classify the samples whose features had been extended. The experimental results showed that the proposed method was more conducive to fault diagnosis of gearbox.

A three-arm robot is designed according to the needs of space operations. Four kinds of climbing are analyzed and the kinematics parameters of the robot are derived. Based on ADAMS virtual prototyping technology, robot modal is established and the climbing process of the robot on a pole is simulated for four kinds of gait, respectively. The force curves and effect factors are obtained so as to offer the design references for the robot.

For reducing the dimensions of feature set and the amount of calculation in fault diagnosis, discrete immunity feature set optimization algorithm is put forward in this paper. Vibration signals are tested from laboratory gearbox under four specific conditions. Twenty-five kinds of feature parameters of those signals are extracted as the initial feature set. Distance-based objective function is established for the algorithm. By discrete binary encoding, immunity cloning, mutation and selection operating, the feature set is optimized. The optimal set includes eleven kinds of feature. Compared with the initial feature set, the application of optimal feature set in gearbox fault diagnosis has reduced computation and improved the diagnostic accuracy and efficiency greatly.

The method to analysis the strength of planetary trains’ carriers of EPB(earth pressure balance) shield machine is presented in this paper. The structure of the shield machine trains is analyzed and the 3-D solid model of the carrier is built with Pro/E. After the load on the carrier has been dealt with, the strength of carrier is calculated by means of finite element method. The results via ANSYS show that the max stress and strain on the carriers are increasing as the increasing load on it. The max stress is lying on the joint point of the carrier and planetary gear shaft because of the bending deformation of the shaft.

Immune theory is applied to independent component analysis in this paper. By elaborated on blind source separation procedure, the blind source separation based on immune optimization algorithm is put forward, that is AIS-ICA algorithm. The paper carried out simulation experiments of mixing and separation for four specific signals. The experimental results show that the convergence speed and separation precision is high, and it has good stability. The new algorithm is used to gearbox vibration signals for blind source separation and fault diagnosis, fault information carried by vibration signals enhanced. Results show that the algorithm used to separate vibration signals of gearbox can greatly enhance fault information, reducing difficulty of gearbox fault diagnosis.

In this paper, a novel studying-training algorithm of wavelet neural-network based on particle swarm optimization (PSO) was presented. Then it was compared with the traditional gradient descent algorithm by the fault classification experiment. The simulation result get a conclusion that the wavelet neural-network trained by PSO not only reduces the iterations, but also get the better convergence precision. It is further indicated that PSO algorithm is fit to train the wavelet neural-network and the optimized network has good signal classification ability.

Fault feature extraction and application is the key technology of fault diagnosis. In this paper, a fault diagnosis method using bispectrum and bispectrum entropy as the fault feature parameters is put forward. Bispectrum entropy as the information entropy in bispectrum domain can reflect the complexity of information energy. When the structure is failed, the distribution of bispectrum will be changed. bispectrum entropy can reflect this change and achieve good separation of the different types of fault. Vibration signal in different bearing states of a secondary drive gearbox is compared and analyzed, bispectrum energy spetrum and bispectrum entropy are extracted. Feature vector is set up via bispectrum entropy for the fault pattern recognition and diagnosis by BP neural network. The analysis result proves that bispectrum entropy is more sensitive to fault characteristic and can separate the fault of bearing.

The wavelet analysis is combined with particle swarm optimization (PSO) which is applied to the de-noise process of vibration responding signals in this paper. The fault information has been enhanced. Furthermore, the signal-noise separation method based on particle swarm optimization for vibration signal and the diagnosis precision enhancement technology are studied, by means of the blind source separation technique.

Blind source separation (BBS) technology was applied to vibration signal processing of gearbox for separating different fault vibration sources and enhancing fault information. An improved BSS algorithm based on particle swarm optimization (PSO) was proposed. It can change the traditional fault-enhancing thought based on de-noising. And it can also solve the practical difficult problem of fault location and low fault diagnosis rate in early stage. It was applied to the vibration signal of gearbox under three working states. The result proves that the BSS greatly enhances fault information and supplies technological method for diagnosis of weak fault.

The corrosion behavior of pure aluminum in FeCl 3 solution was investigated mainly by in-situ AFM (Atomic Force Microscopy). The results of combined researches of AFM, SEM(Scanning Electron Microscopy) and EDAX(Energy Dispersive Analysis of X-ray) show that in addition to uniform attack, pitting corrosion takes place also on pure aluminum surface in FeCl 3 solution at open-circuit potential, and impurity elements Fe and Cu are found enriched in corrosion product. In-situ AFM was also used to examine the initiation and development of pitting corrosion of pure aluminum induced by potentiodynamic sweep, and the repassivation of an active pit is observed. AFM tip scratching technique was used to produce a physical defect on metal surface, which is traced by in-situ AFM and it is found that the defect is likely to be preferentially attacked and evolve to pitting corrosion.

The authors fabricated OTFT devices with different insulator materials. The OTFTs with PMMA as the dielectric layer exhibit better properties, including a mobility of 0.207 cm2 x V1 x s(-1), an on/off current ratio of 4.93 x 10(3), and a threshold voltage of 4.3 V. However, the OTFTs based on oxidized silicon dielectric layer perform not so well, with a mobility of 0.039 cm2 x V(-1) x s(-1), an on/off current ratio of 5.98 x 10(2), and a threshold voltage of 5.4 V. In order to explain the difference in performances, we compared the surface roughness of the oxidized silicon film with that of the PMMA film according to the results of atomic force microscopy, and found that the former had a roughness mean square (RMS) of 1.579 nm and the latter was more smooth with an RMS of 0.216 nm. The quality of the pentacene films deposited onto oxidized silicon and PMMA was also studied by atomic force microscopy and X-ray diffraction. From the results of AFM, the authors found that the pentacene film deposited on PMMA had high thin film quality with larger grain size and less crystal grain boundaries. From the results of XRD, the authors found that the pentacene film deposited on PMMA had clear diffraction peak, showing that the pentacene film deposited on PMMA had greater crystallite quality once again. Therefore, OTFTs with PMMA as insulator layers have advantages over those OTFTs with oxidized silicon dielectric layer.

We have fabricated ZnO-based thin-film transistors (TFTs) by low-cost ultrasonic spray pyrolysis. The devices exhibit high saturation mobility of about 0.6 cm2/Vs and on-off current ratio of 105. The electrical characteristics of ZnO-based TFTs show that ultrasonic spray pyrolysis technique can be used as a promising approach to attain high-performance electronic devices. Furthermore, the deposition techniques make the operating process attractive for flexible electronics.