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A novel calibration method for a multi-line structured laser light vision sensor using a planar target is presented. The method can be summarized as first, the camera model is changed by projecting the point from the two-dimensional (2-D) image plane to the world coordinate system, wherein the intrinsic parameters of the camera are calibrated accurately in advance. Next, by means of a planar target with a cruciform pattern, multiple sets of three-dimensional (3-D) feature points are solved in the camera coordinate system. Last, a new method is proposed for solving the structured light planes in which a uniform objective function is determined and the priori position relation of the structured light planes is considered as a constraint. In this way the prior geometric relation of the planes can be accurately transplanted into the camera coordinate system. Experimental data demonstrate that the proposed method exhibits better accuracy and repeatability. [ABSTRACT FROM AUTHOR]

Solid-state hydrogen storage through the reversible formation of metallic hydrides is a key issue for the development of hydrogen as an energy vector. Herein we report the hydrogen storage performances of the KSiH3 phase ball-milled with NbF5 as a catalyst. The kinetics of hydrogen absorption/desorption are strongly enhanced by the addition of a catalyst as revealed by the large decrease of activation energies for both the absorption and desorption reactions. No disproportionation phenomenon is observed, indicating that the reaction between KSiH3 and KSi is perfectly reversible with a hydrogen storage capacity of 4.1 wt% H2. The thermodynamic properties of this KSi/KSiH3 equilibrium were investigated by plotting PCI curves from 90 °C to 130 °C: an enthalpy of 24.3 kJ mol−1 H2 and a low entropy change of 59.5 J K−1 mol−1 H2 are found. This low entropy variation is related to the high mobility of the H atoms in the α-KSiH3 phase as recently demonstrated by Quasi-Elastic Neutron Scattering (QENS) experiments. [ABSTRACT FROM AUTHOR]

In this paper, the approximate synchronization problem of two non-identical non-linear systems is investigated. Based on the impulsive control method, a sufficient condition is given to guarantee the approximate synchronization. Furthermore, the optimal impulsive interval problem is studied which can reduce the cost of impulsive controller, and the maximum impulsive interval is obtained by solving a non-linear optimization problem via a mixed algorithm combining chaos optimization and linear matrix inequality method. Two different chaotic systems and two different complex dynamical networks are presented respectively to verify the effectiveness of the proposed methods. [ABSTRACT FROM PUBLISHER]

The objective of this study was to assess the radiation exposure levels in victims of a 60Co radiation accident using chromosome aberration analysis and the micronucleus assay. Peripheral blood samples were collected from three victims exposed to 60Co 10 days after the accident and were used for the chromosome aberration and micronucleus assays. After in vitro culture of the lymphocytes, the frequencies of dicentric chromosomes and rings (dic+r) and the numbers of cytokinesis blocking micronuclei (CBMN) in the first mitotic division were determined and used to estimate radiation dosimetry. The Poisson distribution of the frequency of dic+r in lymphocytes was used to assess the uniformity of the exposure to 60Co radiation. Based on the frequency of dic+r in lymphocytes, estimates of radiation exposure of the three victims were 5.61 Gy (A), 2.48 Gy (B) and 2.68 Gy (C). The values were estimated based on the frequencies of CBMN, which were 5.45 Gy (A), 2.78 Gy (B) and 2.84 Gy (C). The estimated radiation dosimetry demonstrated a critical role in estimating the radiation dose and facilitating an accurate clinical diagnosis. Furthermore, the frequencies of dir+r in victims A and B deviated significantly froma normal Poisson distribution. Chromosome aberration analysis offers a reliable means for estimating biological exposure to radiation. In the present study, the micronucleus assay demonstrated a high correlation with the chromosome aberration analysis in determining the radiation dosimetry 10 days after radiation exposure. [ABSTRACT FROM AUTHOR]

Introduction: Pre-pregnancy care (PPC) is an important part of diabetic care among females in the reproductive age group, as it improves feto-maternal outcomes., Objective: We aimed to assess female diabetic patients' perception of PPC and family planning prior to PPC care., Methods: This was an observational, cross-sectional survey performed from June 2019 to September 2019, using universal sampling of registered female diabetic patients who fit the inclusion criteria prior to integrated PPC care. A self-administered questionnaire was used to assess patients' perception of PPC., Results: A total of 67 patients were recruited for the study. Only 39.4% (n=26) of the patients had heard of PPC. In our study, Code 1 contraception included those methods with a Pearl index of ≤9. Code 2 & 3 contraception included those methods with a Pearl index of >9. Only one-third of patients, 29.9% (n=20), were using Code 1 contraception, although the majority, 79.1% (n=53), felt that they had completed their family. 45 patients (68.2%) felt that they were at risk of developing complications if they were to become pregnant, and 46 patients (69.7%) felt that their health condition was not suitable for another pregnancy. However, only 31.1% (n=14) and 34.8% (n=16) of these patients were using Code 1 contraception, respectively. There were 30 patients (65.2%) who perceived that their health was not suitable for another pregnancy but were only using Code 2 or 3 contraception., Conclusion: The patients' perception of PPC was poor. Patients had an inadequate knowledge of the effectiveness of their current contraceptive practice in relation to their intentions for further pregnancy and their self-perceived risk in case of future conception. We suggest that integration of PPC into routine follow-ups for other high-risk medical diseases, such as hypertension, heart disease, and epilepsy, be considered in future practice., (© Academy of Family Physicians of Malaysia.)

As the rapid development of minimally invasive techniques, anesthesia, and enhanced recovery after surgery (ERAS), anorectal day surgery receiving more and more attention by improving efficiency of medical care while reducing cost and hospitalized infection. However, day surgery also faces the challenge of completing the whole process from patient admission to discharge within 24 hours. Therefore, establishing a reasonable and detailed day surgery process is the cornerstone to guarantee safe medical practice and patients satisfaction. National Clinical Research Center for Geriatric Disorders (Xiangya), together with China Ambulatory Surgery Alliance formulates the clinical practice guideline for anorectal day surgery 2019 edition. Here we make some interpretations of the guidelines on the detailed process of anorectal day surgery, including indication, preoperative examination, preoperative risk evaluation, health education, assessment of day surgery anesthesia and before leaving postanesthesia care unit (PACU), postoperative management, assessment of discharge and follow-up, for the convenience of various medical centers.

The objective of this study was to assess the radiation exposure levels in victims of a (60)Co radiation accident using chromosome aberration analysis and the micronucleus assay. Peripheral blood samples were collected from three victims exposed to (60)Co 10 days after the accident and were used for the chromosome aberration and micronucleus assays. After in vitro culture of the lymphocytes, the frequencies of dicentric chromosomes and rings (dic+r) and the numbers of cytokinesis blocking micronuclei (CBMN) in the first mitotic division were determined and used to estimate radiation dosimetry. The Poisson distribution of the frequency of dic+r in lymphocytes was used to assess the uniformity of the exposure to (60)Co radiation. Based on the frequency of dic+r in lymphocytes, estimates of radiation exposure of the three victims were 5.61 Gy (A), 2.48 Gy (B) and 2.68 Gy (C). The values were estimated based on the frequencies of CBMN, which were 5.45 Gy (A), 2.78 Gy (B) and 2.84 Gy (C). The estimated radiation dosimetry demonstrated a critical role in estimating the radiation dose and facilitating an accurate clinical diagnosis. Furthermore, the frequencies of dir+r in victims A and B deviated significantly from a normal Poisson distribution. Chromosome aberration analysis offers a reliable means for estimating biological exposure to radiation. In the present study, the micronucleus assay demonstrated a high correlation with the chromosome aberration analysis in determining the radiation dosimetry 10 days after radiation exposure.

This paper presents an improved neural computation where scheme for kinematic control of redundant manipulators based on infinity-norm joint velocity minimization. Compared with a previous neural network approach to minimum infinity-non kinematic control, the present approach is less complex in terms of cost of architecture. The recurrent neural network explicitly minimizes the maximum component of the joint velocity vector while tracking a desired end-effector trajectory. The end-effector velocity vector for a given task is fed into the neural network from its input and the minimum infinity-norm joint velocity vector is generated at its output instantaneously. Analytical results are given to substantiate the asymptotic stability of the recurrent neural network. The simulation results of a four-degree-of-freedom planar robot arm and a seven-degree-of-freedom industrial robot are presented to show the proposed neural network can effectively compute the minimum infinity-norm solution to redundant manipulators.

This paper presents two neural network approaches to real-time joint torque optimization for kinematically redundant manipulators. Two recurrent neural networks are proposed for determining the minimum driving joint torques of redundant manipulators for the eases without and with taking the joint torque limits into consideration, respectively. The first neural network is called the Lagrangian network and the second one is called the primal-dual network. In both neural-network-based computation schemes, while the desired accelerations of the end-effector for a specific task are given to the neural networks as their inputs, the signals of the minimum driving joint torques are generated as their outputs to drive the manipulator arm. Both proposed recurrent neural networks are shown to be capable of generating minimum stable driving joint torques. In addition, the driving joint torques computed by the primal-dual network are shown never exceeding the joint torque limits.

This article reviews "the forces underpinning Chinese urbanization.... This paper is divided into two main parts. The first addresses the (non-spatial) causal mechanisms between 1949 and 1977. Neither the ideological, the class, nor the economic formulation has touched on the more systemic mechanisms related to the socialist state and the shortage economy. This paper attempts to redress the imbalance by examining the advantages of combining Kornai's shortage model with Foucault's concept of governmentality. By drawing on concepts of spatial contingency, spatial boundary and locality effects, the second part of the paper argues that spatial relations do play significant roles in revealing Chinese urbanisation policies and patterns.", (excerpt)