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The ion optical system is an important component of electron impact (EI) ion source, which uses electrostatic lens to extract ions in the ion chamber, further focus, accelerate and shape, and regulate the speed and energy of the ion beam. The performance of the ion optical system will directly affect the sensitivity and stability of the mass spectrometer. Based on the digital simulation, the ion optical system of EI source can be used to track the movement trajectory of ions from generation to the moment before entering the mass analyzer, which is helpful to deeply understand and recognize the dynamic behavior of ions in the system, and study the key influencing factors of ion movement. In this paper, the ion optical digital simulation system of EI source named Sim-EI-Lens-COM-V1.0 was developed. The geometric structure of each component in the simulation system can be uniformly configured and modified, which is suitable for the simulation of different types of ion optical systems. Based on the developed simulation system, two kinds of typical ion optics with cylindrical and sheet lenses were constructed. The key factors affecting the ion transport efficiency, such as geometric size and voltage parameter of each component in the simulation system, the species and total number of ions produced, and the time of the ion to pass through the system, were studied. Firstly, the influences of the electrostatic lens thickness on the ion dynamic behavior and transport efficiency were investigated. Then appropriate number and initial distribution of ions were selected, and the parametric scanning calculations of the voltage parameters were carried out. Through coarse, fine and precise adjustment of different voltage step values, the optimal voltage combinations of two typical ion optics systems were achieved. The performances of the two ion optical systems were compared under the optimal voltage combination. The result showed that the ion transmission in cylindrical lens ion optical system can reach to 97%, and it can reach more than 99% in sheet lens. The time for ions to pass through the system increases with the increasing of ion mass-charge ratio. The time to pass through the cylindrical lens is shorter than that of the sheet lens under the same ion mass-charge ratio. The radial energy distributions of ions at the outlet of the two ions optical systems are similar, and the axial energy distribution at the outlet of the sheet lens is more concentrated with higher consistency.

Silicone rubber composites with anti-ablation and thermal insulation properties were prepared with hot vulcanized silicone rubber as matrix, and polyarylacetylene, short carbon fiber, zirconia and carbon fiber cloth as anti-ablation fillers, and the effect of anti-ablation fillers on linear ablation rate and substrate temperature of the composites was investigated. The results showed that the linear ablation rate and substrate temperature of the composites were decreased with the sequential addition of the anti-ablation fillers. When the addition amount of polyarylacetylene, short carbon fiber, zirconia, and carbon fiber cloth were all 10 phr (mass), the resul-ting composite had the best anti-ablation and thermal insulation properties with a linear ablation rate of 0.043 mm/s and a substrate temperature of 70 ℃. This was mainly attributed to the ceramization-carbonization coupling reaction between the anti-ablation fillers and silicone rubber matrix, which led to the formation of a dense ablation layer that covered the surface of carbon fiber cloth.

Objective: Metabolomics based on ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF-MS) was applied to explore the metabolic changes in the urine of mice with Alzheimer’s disease (AD) after intervention with camellia oil. Methods: Mice were randomly divided into four groups: normal control, AD model, positive drug and camellia oil treatment. In all mice except for those in the control group, AD was induced by amyloid β-protein (Aβ) 25-35 peptide, and urine samples were collected from each group for UPLC-Q/TOF-MS analysis after protein precipitation. The obtain urine metabolite data were analyzed by the SIMCA-P14.1 software with principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA). Using the online databases of HMBD, MassBank, MetaboAnalyst and Kyoto Encyclopedia of Genes and Genomes (KEGG), biomarker identification, pathway enrichment analysis, and metabolic network construction were conducted. Results: In the PCA score plots, the camellia oil group was clearly separated from the model group and closer to the normal group. Totally 48 biomarkers were identified and the major pathways involved were taurine and hypotaurine metabolism, arginine and proline metabolism, cysteine and methionine metabolism, alanine, aspartate and glutamate metabolism. Conclusion: Camellia oil can improve the metabolism of AD mice by regulating energy metabolism, amino acid metabolism and other pathways, which provides a reference for further study of camellia oil intervention against AD.

Amyloid light (AL) amyloidosis, also known as primary systemic amyloidosis, is a protein conformation disease, and is a clinical syndrome of functional failure of affected organs due to abnormal folding and deposition of insoluble fibrin in the extracellular region of organs or tissues. The diagnosis of AL-type amyloidosis is challenging because of its low incidence and complex clinical manifestations, and cases of multiple organ involvement are even rarer. We reported a case of AL-type amyloidosis with multiple organ involvement in order to provide refference for related diagnosis, treatment and prognosis.

Preparation of cerium oxide by conventional liquid phase method has the disadvantages of complex technological process and effluent discharge. Spray pyrolysis for making CeO2 has the disadvantages of nozzle plugging, and this traditional heating method produces a significant temperature gradient that results in unevenly heated reactants. To prevent the above issues, this study proposed an effective and environmental experimental scheme. Cerium chloride heptahydrate and deionized water were utilized for the raw material. High-purity nano cerium oxide particles were prepared by jet-flow pyrolysis technology via microwave heating. Combining the technology of microwave heating with jet-flow pyrolysis, whose Venturi reactor served as the primary piece of equipment, can improve the mixing of gas and liquid, increase chemical reaction efficiency, and reduce carbon emissions. It was a new effort in the area of pyrolysis. To visually analyze the distribution of each physical field and substance, numerical simulation was combined with x-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy to characterize the products. Effects of the various technological conditions (pyrolysis temperature, gas velocity, and adding citric acid) on the content of residual chloride element and microstructure of the product were examined. Results demonstrated that the temperature error between the experiment and simulation was below 20 ℃ with the condition of the same microwave power. When the pyrolysis temperature was at 500 ℃, CeO2 could be produced in a single phase, but the particle profile was unclear. The particles had sharp profiles when the temperature was 600 ℃. Nanoscale spherical CeO2 particles appeared when the average temperature reached 700 ℃. The results of the study’s simulations and experiments indicated that higher temperatures were associated with more regular microcosmic morphology and a lower content of residual chloride element. Increasing the gas velocity caused an obvious decrease in the average temperature, which led to more content of residual chloride elements. However, the gas collided with the solution more fiercely, which improved the mixing of the two phases. Experimental and simulated results showed that when gas velocity reached 1.2 m∙s−1, better dispersity and less agglomeration of the product were obtained. Additionally, the residual chloride content was less than 1%. Because a significant amount of CO2 was produced during the burning of the citric acid, the spherical cerium oxide particles broke into irregular particles. Porous structures also appeared when citric acid was added. The residual chloride content decreased with the increase of citric acid concentration when citric acid concentration was greater than 0.05 mol·L−1.

By An amphibious bionic robot has good movement ability under several working conditions, so as to better perform tasks in complex terrain environments. In this study, the development background, research status and main applications of amphibious bionic robots are summarized. According to the degree of bionic reference, amphibious bionic robots are divided into two categories: imitating motion mode and imitating motion structure. The relevant research is introduced and the characteristics of different robot types are analyzed. Furthermore, the technical advantages and typical application scenarios of amphibious bionic robots are described.

For laser products, safety certification is a mandatory requirement for international market access. For the standard application of certification, it is suitable for common laser product, but has less operability for optical fibre communication products. In order to make the evaluation of laser safety classification clear, this research is accomplished based on the general requirements of international laser safety standards and the application of optical fibre communication products and its characteristics. This research brings up a comprehensive discussion on measurement geometry, laser safety classification, automatic power reduction technology and safety design requirements. This research proposes a process and method for laser safety classification judgement. It also provides two verified test methods of automatic power reduction action time and the irradiance or radiant exposure during the maximum time interval. This research can provide a useful reference for laser safety design, classification, test and laser safety level certification of optical fibre communication products.

To improve the capacity building of research and practical skills of postgraduates majoring in pathogen biology, a “co-tutors”training mode was developed. The first tutor was mainly responsible for the theoretical education and scientific research training, and the second tutor is mainly responsible for the training of students'practical skills.The mode was combined with a “closed-loop” quality control system to supervise the training of g postgraduates along with high-quality papers. This training program supported capacity building of research and practial skills.

The identification of the number of function argument contributes to the recovery of the function prototype and is the basis for data flow analysis and other security analysis. In order to improve the accuracy of the recognition of the number of function parameters, an algorithm (Findargs) which determines the number of parameters of the function according to the voting mechanism of the function call relationship was proposed. Findargs starts from the function call characteristics of PPC and MIPS instruction set, and uses function call relationship combined with argument pass analysis to identify the number of function arguments, which can help to recover function prototype. In order to evaluate the recognition effect of Findargs, a large binary file was selected and tested it with radare2. The experiments results show that Findargs has higher accuracy, and the accuracy rate for PPC instruction set reaches 90.3%. For MIPS instruction set, the accuracy rate is 86%.

Traditional machine learning models works in peace environment,assuming that training data and test data share the same distribution.However,the hypothesis does not hold in areas like malicious document detection.The enemy attacks the classification algorithm by modifying the test samples so that the well-constructed malicious samples can escape the detection by machine learning models.To improve the security of machine learning algorithms,moving target defense (MTD) based method was proposed to enhance the robustness.Experimental results show that the proposed method could effectively resist the evasion attack to detection algorithm by dynamic transformation in the stages of algorithm model,feature selection and result output.

Patch comparison provides support for software vulnerability,and structural comparison has been developed.Based on summarizing binary files comparison and anti-comparison methods,comparison technology was proposed by semantic analysis on function to address the issue that structural comparison cannot carry on semantic analysis.Through traditional structural comparison,syntax differences in function-level were analyzed to find the maximum common subgraph.Then,the path cluster was built between the input and output of the function depend on program dependency analysis.Function output characteristics was established based on symbolic execution.Semantic differences of functions were compared by functional summaries.Based on the maximum isomorphic subgraph,the matched functions which there are possible semantic changes between was further analyzed.Ultimately,the experimental results showed the feasibility and advantages of the proposed method.

Methyl vinyl silicone rubber and methyl vinyl phenyl silicone rubber were used as the matrix, silica and boron phenolic resin (BF) were added for mixing, a light ablative heat insulation material was prepared. The density of the heat insulation material, the ablative performance of the heat insulation material under oxygen-acetylene flame and the back temperature of the material in the ablative process were studied. The results showed that with the addition of BF, the density of thermal insulation materials decreased significantly. When the amount of BF was 40 phr and 50 phr (mass, the same below), the density was 0.816 7 g/cm3 and 0.752 8 g/cm3 respectively, which was 29.35% and 34.88% lower than that without BF. With the increasing amount of BF, the mass ablation rate and linear ablation rate of the thermal insulation material increased, but the addition of BF could enhance the thermal insulation performance of the material. When 40 phr BF were added, the maximum back temperature was only 78 ℃.

LEO satellite networks can provide seamless real-time data communication for all kinds of users,which developed rapidly in recent years.At the mean time,the massive payload data down-link system of space data sources,such as remote sensing satellites,still make use of traditional storage and forward mode.The real-time performance of space mission data will be improved effectively,if such satellites are connected to LEO satellite networks equipped with inter satellite links.However,it is necessary to design a specialized satellite network load balancing routing algorithm.Satellite parallel edge-disjoint multipath routing protocol (SPEMR) was designed for remote sensing satellite real-time down-link applications.OPNET simulation results indicate that the performance degradation index(DI) of the multipath scheme implemented by SPEMR is 0.32,which is only 32% of the TLR and 21% of the traditional DSP scheme.It is demonstrated that SPEMR has the better capability of transmitting massive data in real time.

In order to discuss the transport phenomena and the physical properties of the doping of the disorder system under magnetic field, the electron transport in a two-dimensional system is studied by using Green function and scattering matrix theory. Base on the two-dimensional lattice model, the phenomenon of quantized conductance of the "sandwich" type electronic system is analyzed. The contact between the lead and the scatterer reduce the system's conductance, and whittle down the quantum conductance stair-stepping phenomenon; when an external magnetic field acts on to the system, the conductance presents a periodicity oscillation with the magnetic field. The intensity of this oscillation is related to the energy of the electron;with the increase of the impurity concentration, the conductance decreases.In some special doping concentration, the conductance of the system can reach the ideal step value corresponding to some special electron energy. The result could provide reference for further study of the conductance of the "sandwich" type two dimensional system.

The functions and characteristics of current IOV(Internet of vehicles) Internet of vehicles were analyzed.Moreover,combined with 5G communication technology,the architecture of IOV for 5G was proposed to imple-ment access and integration of multi-network.Different from the IEEE 802.11p based architecture of VANET,de-vice-to-device (D2D) technology was introduced to achieve flexible terminals communication of IOV.In comparing with VANET based on IEEE 802.11p in terms of key technology parameters,the IOV for 5G possesses the better characteristics in terms of low latency and efficient spectrum utilization,and also need to face new interference management and security challenges.At the end,the application and development trends of IOV for 5G in the busi-ness and the specific environment were prospected.

To reduce the total cost of P2P cache system, a cooperative cache scheme based on the minimization of total cost is proposed. In the scheme, delivery cost and storage cost are taken into account, and inter-ISP cost, popularity, file size, storage cost are used to evaluate each object's caching gain value, which is a new concept defined to estimate the benefits of storing or replacing an object. When a replacement is needed, the objects with the minimum caching gain value will be evicted. Simulation results show that the proposed scheme can effectively reduce the total cost of P2P cache system.

Aiming at the complex in the process of network security risk assessment, the asset, vulnerability and threat were used as the major factors in security assessment to establish the hierarchical index system for security assessment. The concept of credibility was introduced, and the security risk assessment model and fuzzy reasoning algorithm based on fuzzy Petri net were also proposed, making use of fuzzy Petri nets method joined together with the AHP to analyze the question, and combining qualitative analysis and quantitative analysis together. The example analysis shows that the ob-tained results are more accurate and scientific compared with traditional assessment methods. Therefore, this method is an effective network system risk assessment method.

The spacial and temporal character of motion vector were analysed according to the spacial and temporal characteristic of motion vector,the different proposed search schemes were adopted for motion estimation;The experimental results shows the proposed algorithm reduce the prediction error and has a significant computational speedup compared with other algorithms,but offers a similar,even better performance.

As the increment of services with same function and different QoS in the internet,in order to select and rank the services that fulfill users’ functionality requirements and QoS requirements,a multi-strategy QoS-aware service ranking and selection approach is presented.Considering service performance,and service operation,maintenance costs,an extended Web service QoS model was developed.To determine how well a service satisfies users’and operators’ concerned QoS requirements,a set of functions is presented to normalize services’QoS on various QoS aspects with different metrics and scales,also to compute services satisfaction scores ,and to combine the users’satisfaction scores and the operators’scores together as an overall satisfaction scores based on certain strategy.A prototype system was built for service selection and ranking,and the model above was verified through an application case.

Background: Sexual violence is a global health and human rights issue that impacts the physical and mental health of victims and increases healthcare costs. Purpose: This research was developed to investigate the prevalence of sexual violence against women in Taiwan and the help-seeking behavior of these women. Based on the findings, suggestions are provided for both government policymakers and frontline medical staffs. Methods: Data for this study were collected using a face-to-face interview survey conducted with women aged 18 to 74 years nationwide. Results: Of the 1,504 women surveyed, 87 (5.76%) reported having suffered from sexual violence. The one-year prevalence was 1.41%, while the lifetime prevalence was 5.76%. Although sexual violence is known to impact physical and mental health, most victims are reluctant to seek help from formal support systems. Conclusions: Victims of sexual violence often delay seeking help from medical settings. Although the victims identified in this study endured chronic symptoms and psychological trauma, few had made formal disclosures of intimate partner sexual violence (IPSV) incidents. Frontline medical staffs have the opportunity to play an important role in sexual-violence response if they are made aware of incidents of IPSV/non-IPSV. Thus, to facilitate disclosure, screening for IPSV and non-IPSV should be made standard practice in high-risk medical settings. [ABSTRACT FROM AUTHOR]

In a period of cultural crisis, a significant mission of philosophers is to provide a framework for the re-establishment of cultural self-identity. The purpose of this framework is to facilitate the self-transformation of cultures, and the aim of this is to regain the ground of legitimation for the sake of cultural evolution. This paper compares the cultural critique of Dai Zhen (1724-1777) and Nietzsche (1844-1900) and explores the cultural self-transformation strategies which are implied in their cultural critiques. I describe how these two philosophers faced the crisis of their own culture (Confucian. ism and Platonism-Christianity) and what approaches they used to transcend their culture. We can draw a parallel between Dai Zhen's efforts and Nietzsche's efforts to reconstruct their own cultural traditions. There are some similar- ities to be found in their cultural reconstructions, which also signify a trans- formation of thought structure. The cultural critiques of Dai Zhen and Nietzsche implicitly put forth the following: 1. an emphasis on the individual 2. an emphasis on the naturalness of the human being 3. the body as a basis for human conduct. These require a refutation of the transcendental identity of the norm but an acceptance of the empirical aspects of human nature. On the one hand, Dai Zhen and Nietzsche emphasize the concreteness and particularity of the individual; on the other hand, they try to provide a necessary code of conduct from the perspective of naturalistic holism, using the body as a basis for human conduct. We examine whether the cultural critiques of Dai Zhen and Nietzsche can be seen as a test of the philosophy of body to provide a code of conduct for every individual. There are two possible outcomes for this trial: either Dai Zhen and Nietzsche can achieve their goal of cultural self- transformation, or, the revaluations of their cultural matrices are nothing but an accelerated destruction of cultural and traditional core values. [ABSTRACT FROM AUTHOR]

This work was launched to study on the chemical constituents from Euphorbia thymifolia. Thirteen compounds were isolated from the 95% ethanol extract of the aerial parts of E. thymifolia by column chromatographies on silica gel, Sephadex LH-20, MCI, and ODS, and preparative HPLC, including two thymol derivatives(1-2), four alkaloids(3-6), five isocoumarins(7-11), together with two ellagic acids(12-13). All the compounds are listed as follows:(Z)-8,9-dehydro-9,10-diisobutyryloxythymol(1), 8-hydro-xy-9,10-diisobutyryloxythymol(2), N-(N-benzoyl-L-phenylalanyl)-L-phenylalanol(3), aurantiamide acetate(4), 1-carboethoxy-β-carboline(5), isoechinulin A(6), ethyl brevifolincarboxylate(7), euphorhirtin B(8), 4,5-didehydro chebulic acid triethyl ester(9), euphorhirtin G(10), pomegranatate(11), 3,3',4'-tri-O-methylellagic acid(12), 3,3'-di-O-methylellagic acid(13). Compound 1 is a new compound. Except for compound 4, the others were isolated from this plant for the first time. All the compounds were screened for anti-neuroinflammatory activity in vitro, and compounds 1-3 and 7 showed significant activity with IC_(50) values of 0.19,12.93,7.29,25.4 μmol·L~(-1).