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We develop computational mechanical modeling and methods for the analysis and simulation of the motions of a human body. This type of work is crucial in many aspects of human life, ranging from comfort in riding, the motion of aged persons, sports performance and injuries, and many ergonomic issues. A prevailing approach for human motion studies is through lumped parameter models containing discrete masses for the parts of the human body with empirically determined spring, mass, damping coefficients. Such models have been effective to some extent; however, a much more faithful modeling method is to model the human body as it is, namely, as a continuum. We present this approach, and for comparison, we choose two digital CAD models of mannequins for a standing human body, one from the versatile software package LS‐DYNA and another from open resources with some of our own adaptations. Our basic view in this paper is to regard human motion as a perturbation and vibration from an equilibrium position which is upright standing. A linear elastodynamic model is chosen for modal analysis, but a full nonlinear viscoelastoplastic extension is possible for full‐body simulation. The motion and vibration of these two mannequin models is analyzed by modal analysis, where the normal vibration modes are determined. LS‐DYNA is used as the supercomputing and simulation platform. Four sets of low‐frequency modes are tabulated, discussed, visualized, and compared. Higher frequency modes are also selectively displayed. We have found that these modes of motion and vibration form intrinsic basic modes of biomechanical motion of the human body. This view is supported by our finding of the upright walking motion as a low‐frequency mode in modal analysis. Such a "walking mode" shows the in‐phase and out‐of‐phase movements between the legs and arms on the left and right sides of a human body, implying that this walking motion is spontaneous, likely not requiring any directives from the brain. Dynamic motions of CAD mannequins are also simulated by drop tests for comparisons and the validity of the models is discussed through Fourier frequency analysis. All computed modes of motion are collected in several sets of video animations for ease of visualization. Samples of LS‐DYNA computer codes are also included for possible use by other researchers. [ABSTRACT FROM AUTHOR]

In this paper, we were concerned with the global behavior of positive solutions for third-order semipositone problems with an integral boundary condition y ‴ + β y ″ + α y ′ + λ f (t , y) = 0 , t ∈ (0 , 1) , y (0) = y ′ (0) = 0 , y (1) = χ ∫ 0 1 y (s) d s , where α ∈ (0 , ∞) and β ∈ (− ∞ , ∞) are two constants, λ , χ are two positive parameters, and f ∈ C ([ 0 , 1 ] × [ 0 , ∞) , R) with f (t , 0) < 0 . Our analysis mainly relied on the bifurcation theory. In this paper, we were concerned with the global behavior of positive solutions for third-order semipositone problems with an integral boundary condition where and are two constants, are two positive parameters, and with . Our analysis mainly relied on the bifurcation theory. [ABSTRACT FROM AUTHOR]

In this article, we investigate the optimal component allocation policy (CAP) for series [parallel] system with series subsystems under random shock environment, wherein the components in each series subsystem are dependent and the series subsystems are independent of each other. The dependence of the components in each series subsystem under shock are modeled by an Archimedean copula. We consider the extreme and cumulative shock models, in which the shock process for each series subsystem is described by a non-homogeneous Poisson process. We compare systems with different component allocation policies in the sense of hazard rate order and usual stochastic order. We also study the influence of the number of the series subsystems on the system reliability. Finally, we analyze the aging properties of the system under the extreme shock model. [ABSTRACT FROM AUTHOR]

To investigate the effect of information transmission, Lévy jumps and contact heterogeneity of individuals on the asymptotic behavior of epidemic, a stochastic SIQR epidemic model with non-monotone incidence rate and Lévy jumps on scale-free networks is constructed. At first, the global dynamics of the deterministic model is studied by constructing appropriate Lyapunov functions. Then the stochastic model is made in accordance with the ecological significance, the existence and uniqueness of the global positive solution of the stochastic SIQR model is manifested. Next, by constructing suitable stochastic Lyapunov functions and applying Itô formula with jump, the asymptotic behavior of solutions of stochastic model around equilibrium of the corresponding deterministic model is checked. At last, the correctness of the analytical results is verified by numerical simulations. [ABSTRACT FROM AUTHOR]

The No. 147 guiding case of the Supreme People's Court set a precedent for the crime of intentionally destroying scenic spots and historic sites in Article 324 (2) of the Criminal Law to protect scenic resources. Its significance lies not only in the innovation of judgment thinking, but also in the reconfirmation of the criminal law protection of scenic resources. In order to further define the trial philosophy of guiding case No. 147, resolve the dilemmas in the judicial determination of crimes of intentionally destroying scenic spots and historic sites, and clarify the boundaries of power and rights in the field of ecological environment, administrative violations, and criminal crimes, this paper adopts the three-stage analysis framework of ' object - transgression - legal interest' to construct the paths of the criminal law protection of scenic resources. In terms of the definition of the objects involved, ' scenic resources' in the crime of intentionally destroying scenic spots and historic sites should be defined as the ecological landscape rather than the ecological scenic spots so as to maintain the coordination of criminal protection between natural reserves, national parks, and scenic spots. When identifying ' damaging behaviors,' we propose the concept of ' nested regulation theory' with ' destroying' scenic resources as the main standard, supplemented by ' value reduction' to clarify the boundary between illegal and criminal behaviors and to avoid excessive severity of criminal identification. In the restatement of legal interest value, the ' 1+X' model is adopted to summarize the legal interest value characteristics of scenic resources: ' 1' refers to the basic and original ecological legal interest characteristics of these resources; 'X' refers to the legal interest attributes of cultural relics contained in scenic resources as natural and humanistic heritage, which can be further divided into biological legal interest value, enlightening legal interest value, aesthetic legal interest value, and economic legal interest value. Different types of legal interest value are endowed with different meanings for the criminal identification of ' serious damages. ' The ' destruction' of ecological legal interests, biological legal interests, and scientific research value is the condition under which the criminal law initiates the protection of scenic resources; however, the 'value reduction' of popular science value and aesthetic legal interests is the condition under which the criminal law initiates the protection of scenic resources. The economic legal interests of scenic resources do not affect the judgment of criminal illegality. [ABSTRACT FROM AUTHOR]