Refinement modeling and verification of secure operating systems for communication in digital twins

In traditional digital twin communication system testing,we can apply test cases as completely as possible in order to ensure the correctness of the system implementation,and even then,there is no guarantee that the digital twin communication system implementation is completely correct.Formal verification is currently recognized as a method to ensure the correctness of software system for communication in digital twins because it uses rigorous mathematical methods to verify the correctness of systems for communication in digital twins and can effectively help system designers determine whether the system is designed and implemented correctly.In this paper,we use the interactive theorem proving tool Isabelle/HOL to construct the formal model of the X86 architecture,and to model the related assembly instructions.The verification result shows that the system states obtained after the operations of relevant assembly instructions is consistent with the expected states,indicating that the system meets the design expectations.

Tone Task Proves Blind Hear Better--Early vision loss leads to keener hearing

盲人音乐家的才华洋溢是纯属巧合,还是由于潜能的凝聚呢?加拿大的科学家们发现:年幼失明的盲者对于乐音变化的察觉能力确实远远强于后天失明者及普通人。

汽车可靠性道路试验仿真研究

应用Virtual Proving Ground软件进行汽车试验场可靠性道路试验的仿真研究,对交通部公路交通试验场标准搓板路面进行了三维实体建模,按照可靠性试验规范,在标准搓板路上对某国产轿车进行了计算机仿真,并与实车试验典型测点加速度-时间历程数据进行对比,具有很好的相似性;并对车辆模型进行了初步的可靠性分析。研究结果为进一步进行汽车可靠性耐久性研究提供了一定依据。

Exact solutions for nonlinear partial fractional differential equations

′In this article, we use the fractional complex transformation to convert nonlinear partial fractional differential equations to nonlinear ordinary differential equations. We use the improved （G′/G）-expansion function method to calculate the exact solutions to the time- and space-fractional derivative foam drainage equation and the time- and space-fractional derivative nonlinear KdV equation. This method is efficient and powerful for solving wide classes of nonlinear evolution fractional order equations.

A new complex variable element-free Galerkin method for two-dimensional potential problems

In this paper, based on the element-free Galerkin （EFG） method and the improved complex variable moving least- square （ICVMLS） approximation, a new meshless method, which is the improved complex variable element-free Galerkin （ICVEFG） method for two-dimensional potential problems, is presented. In the method, the integral weak form of control equations is employed, and the Lagrange multiplier is used to apply the essential boundary conditions. Then the corresponding formulas of the ICVEFG method for two-dimensional potential problems are obtained. Compared with the complex variable moving least-square （CVMLS） approximation proposed by Cheng, the functional in the ICVMLS approximation has an explicit physical meaning. Furthermore, the ICVEFG method has greater computational precision and efficiency. Three numerical examples are given to show the validity of the proposed method.

CLINICAL AND EXPERIMENTAL STUDIES OF JPYS IN REDUCING SIDE-EFFECTS OF CHEMOTHERAPY IN LATE-STAGE GASTRIC CANCER

This article reports a research project undertaken for more than 16 years by the Cancer Depart-ment of Guang An Men Hospital.Tonic Jian Pi Yi Shen (JPYS 健脾益肾),which nourishes thespleen and kidney,was used in combination with chemotherapy in the treatment of late stage gas-tric cancer patients for the purpose of promoting completion of the chemotherapeutic course,im-proving the general condition,ameliorating the reaction in the digestive system,protectinghemopoiesis and strengthening immunocompetence.The results of lab experiments were found tocoincide with those of clinical application.

A Case of Senile Vaginitis Treated by Acupuncture

The article records details of the treatment process and efect of an elderly patient with senile vaginitis,where needling,a method of Chinese Traditional Medicine(TCM)method,was applied mainly,combined with oral administration of western medicine.It then analyses this disease from prospective of TCM.In the end,it concludes that no matter traditional needling method or traditional needling method combined with moxibustion,it has achieved a satisfied treatment effect while applying needling on chosen acupuncture points,so it is worthy being further popularized.

FEA OF RUBBER WITH NOVEL STRAIN ENERGY FUNCTIONS

This paper presents the results of finite element analysis of rubber structures based on novel strain energy functions stemming from the representation theorem of tensorial function. The stress tensor is represented by Taylor expansion, using the representation theorem of tensorial function of a single tensorial argument for all terms in each order of the expansion. The scalar-valued coefficient functions of the theorem are represented by the integrity bases of the strain tensor and material constants to be determined by experiment. The computer implementation of the new constitutive laws has been verified by comparing the FE results with analytical solutions. A complicated structure of rubber bearing was analyzed. The FE results show good correlation with experimental data.

Automatic Generation of Very Efficient Programs by Generalized Partial Computation

Generalized Partial Computation (GPC) is a program transformation method utilizing partial information about input data, properties of auxiliary functions and the logical structure of a source program. GPC uses both an inference engine such as a theorem prover and a classical partial evaluator to optimize programs. Therefore, GPC is more powerful than classical partial evaluators but harder to implement and control. We have implemented an experimental GPC system called WSDFU (Waseda Simplify Distribute Fold Unfold). This paper discusses the power of the program transformation system, its theorem prover and future works.

Decision Making as Theorem Proving

We present a method for using type theory to solve decision making problem. Our method is based on the view that decision making is a special kind of theorem proving activity. An isomorphism between problems and types, and solutions and programs has been established to support this view which is much similar to the Curry-Howard isomorphism between propositions and types, and proofs and programs. To support our method, a proof development system called PowerEpsilon has been developed, and the synthesis of a decision procedure for validity of first-order propositional logic is discussed to show the power of the system.

The Design and Implementation of a Program Development System Based on Rewriting Method

This paper presents a program development system based on rewriting techniques. An introduction to an earlier version of the system without the verification system can be found in [1]. This paper focuses on the verification subsystem which is designed to prove the correctness of the optimization rules and test equations in programs and specifications, hence to further guarantee the soundness of the program development process. The main technique employed in the verification subsystem is rewriting induction featured with batch proof method and witnessed test sets.

Extending the Strand Space Method with Timestamps: Part II Application to Kerberos V

In this paper, we show how to use the novel extended strand space method to verify Kerberos V. First, we formally model novel semantical features in Kerberos V such as timestamps and protocol mixture in this new framework. Second, we apply unsolicited authentication test to prove its secrecy and authentication goals of Kerberos V. Our formalization and proof in this case study have been mechanized using Isabelle/HOL.

Extending the Strand Space Method with Timestamps: Part I the Theory

In this paper, we present two extensions of the strand space method to model Kerberos V. First, we include time and timestamps to model security protocols with timestamps: we relate a key to a crack time and combine it with timestamps in order to define a notion of recency. Therefore, we can check replay attacks in this new framework. Second, we extend the classic strand space theory to model protocol mixture. The main idea is to introduce a new relation to model the causal relation between one primary protocol session and one of its following secondary protocol session. Accordingly, we also extend the definition of unsolicited authentication test.

Status-quo of proved oil/gas initially-in-place in China as of 2020 and its variation trend in the past decade

This study analyzes the status-quo of the proved oil/gas initially-in-place and its variation trend,the proved undeveloped oil/gas initially-in-place,and the remaining proved technically recoverable reserves(TRR)of oil/gas in China as of 2020 based on statistics.As shown by the results,the proved oil initially-in-place(OIIP),the proved undeveloped OIIP,and the remaining proved TRR of oil in China are mainly distributed in the Bohai Bay,Ordos and Songliao Basins,and those of free gas are mainly in the Ordos,Sichuan,and Tarim Basins.From 2011 to 2020,the largest increment in the proved OIIP,the proved undeveloped OIIP and the remaining proved TRR of oil occurred in the Ordos Basin,followed by the Bohai Bay Basin,while that in the proved gas initially-in-place(GIIP),the proved undeveloped GIIP,and the remaining proved TRR of gas occurred in the Ordos Basin,followed by the Sichuan Basin.In addition,a comprehensive analysis reveals that the petroliferous basins in China with the potential of reserve addition and production growth include the Ordos Basin,the Bohai Bay Basin,the Sichuan Basin,and the Tarim Basin.

Proving Inequalities

Proving inequalities means to establish that theinequality holds true for arbitrary admissible valuesof the parameters.Example 1:Prove that the absolute value of asum does not exceed the sum of the absolute values:|a+b|≤|a|+|b|.①Proof.The absolute value of the sum |a+b| isequal to a+b or to -(a+b).From the definition ofthe absolute value we havea≤|a|,b≤|b|and combining these inequalities termwise,we geta+b≤|a|+|b|.②In exactly the same manner,-a≤|a|,-b<|b| and-(a+b)≤|a|+|b|.③From the inequalities ②,③ and the definition of

The New Standards System for Processing Food to Be Proved

It is reported that the work of re-structuring the frame of China nationalstandards system for processing food has been finished with the print and distribution of 2004-2005Development Plan of National Standards for Food (hereinafter Plan). According to the demand of thePlan, there will be great changes among the current national standards and the professionalstandards for processing food, in which some standards will be integrated with others, somestandards will be cancelled, and some will be brought into the new standards system after the reviewof standards. The standards after being changed and the new national standards and the professionalstandards that need to be developed compose the new standards system for processing food.