The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the ...The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications.展开更多
A transformation of the electron states—say those enclosed in a potential box—into the de Broglie waves done in the paper, enabled us to calculate the energy change between two quantum levels as a function of the sp...A transformation of the electron states—say those enclosed in a potential box—into the de Broglie waves done in the paper, enabled us to calculate the energy change between two quantum levels as a function of the specific heat and difference of the temperature between the states. In consequence, the energy difference and that of entropy between the levels could be examined in terms of the appropriate classical parameters. In the next step, the time interval necessary for the electron transition between the levels could be associated with the classical electrodynamical parameters like the electric resistance and capacitance connected with the temporary formation of the electric cell in course of the transition. The parameters characterizing the mechanical inertia of the electron were next used as a check of the electrodynamical formulae referring to transition.展开更多
Many evidences for gas hydrate bearing sediments had been found in the continental slope of the East China Sea,such as bottom simulating reflections(BSRs),undersea gas springs,pyrite associated with methane leakage,mu...Many evidences for gas hydrate bearing sediments had been found in the continental slope of the East China Sea,such as bottom simulating reflections(BSRs),undersea gas springs,pyrite associated with methane leakage,mud diapirs/mud volcanos,bottom-water methane anomalies and so on.In this study,six key stratigraphic interfaces including T_0(seafloor),T_1(LGM,23 kyr B.P.),T_2(2.58 Myr),T_3(5.33 Myr),T_4(11.02 Myr)and T_5(16.12 Myr)were identified,and then five third-order sequences of SQIII1 to SQIII5 were divided.However,T5 in southern continental slope is not found,which shows that the middle-northern Okinawa Trough had begun to rift in the early Miocene,earlier than the southern segment.Four system tracts including lowstand systems tract(LST),transgressive systems tract(TST),highstand systems tract(HST)and falling stage systems tract(FSST)are further divided.The marine erosion interface of 11.02 Myr and regressive unconformity interface of 23 kyr B.P.indicate two large-scale sea level drop events in the research area.Seven typical seismic facies identified in the continental slope are continental shelf-edge deltas,littoral fluvial-delta plains,incised channels or submarine canyons,slope fans,submarine fans or coastal sandbars,littoral-neritic finegrained sediments,mud volcanos and some other geological bodies respectively.The minimum water depth for hydrate occurrence in the Okinawa Trough is 630 m,and the thickness of gas hydrate stability zone in continental slope is between 0 and 590 m.The calculated bottom boundary of hydrate stability zone is slightly deeper than BSRs on the seismic sections.The re-depositional turbidite sand bodies,such as canyon channels,slope fans and submarine fans developed in Quaternary strata,are the predominant hydrate reservoirs.According to developing process,the dynamic accumulation of hydrate systems can be divided into three evolutionary stages including canyon erosion and hydrate stability zone migration stage,sediments destabilizing and methane leakage stage,and channel filling and hydrate re-occurrence stage.展开更多
Safety assessment of genetically modified organisms (GMOs) is a contentious topic. Proponents of GMOs assert that GMOs are safe since the FDA’s policy of substantial equivalence considers GMOs “equivalent” to their...Safety assessment of genetically modified organisms (GMOs) is a contentious topic. Proponents of GMOs assert that GMOs are safe since the FDA’s policy of substantial equivalence considers GMOs “equivalent” to their non-GMO counterparts, and argue that genetic modification (GM) is simply an extension of a “natural” process of plant breeding, a form of “genetic modification”, though done over longer time scales. Anti-GMO activists counter that GMOs are unsafe since substantial equivalence is unscientific and outdated since it originates in the 1970s to assess safety of medical devices, which are not comparable to the complexity of biological systems, and contend that targeted GM is not plant breeding. The heart of the debate appears to be on the methodology used to determine criteria for substantial equivalence. Systems biology, which aims to understand complexity of the whole organism, as a system, rather than just studying its parts in a reductionist manner, may provide a framework to determine appropriate criteria, as it recognizes that GM, small or large, may affect emergent properties of the whole system. Herein, a promising computational systems biology method couples known perturbations on five biomolecules caused by the CP4 EPSPS GM of Glycine max L. (soybean), with an integrative model of C1 metabolism and oxidative stress (two molecular systems critical to plant function). The results predict significant accumulation of formaldehyde and concomitant depletion of glutathione in the GMO, suggesting how a “small” and single GM creates “large” and systemic perturbations to molecular systems equilibria. Regulatory agencies, currently reviewing rules for GMO safety, may wish to adopt a systems biology approach using a combination of in silico, computational methods used herein, and subsequent targeted experimental in vitro and in vivo designs, to develop a systems understanding of “equivalence” using biomarkers, such as formaldehyde and glutathione, which predict metabolic disruptions, towards modernizing the safety assessment of GMOs.展开更多
This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends t...This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends that they are not the same. The concept of cyber security is explored, which goes beyond protecting information resources to include a wider variety of assets, including people [1]. Protecting information assets is the main goal of traditional information security, with consideration to the human element and how people fit into the security process. On the other hand, cyber security adds a new level of complexity, as people might unintentionally contribute to or become targets of cyberattacks. This aspect presents moral questions since it is becoming more widely accepted that society has a duty to protect weaker members of society, including children [1]. The study emphasizes how important cyber security is on a larger scale, with many countries creating plans and laws to counteract cyberattacks. Nevertheless, a lot of these sources frequently neglect to define the differences or the relationship between information security and cyber security [1]. The paper focus on differentiating between cybersecurity and information security on a larger scale. The study also highlights other areas of cybersecurity which includes defending people, social norms, and vital infrastructure from threats that arise from online in addition to information and technology protection. It contends that ethical issues and the human factor are becoming more and more important in protecting assets in the digital age, and that cyber security is a paradigm shift in this regard [1].展开更多
A brief review of the works of the author and his co-authors on the application of nonlinear analysis, numerical and analytical methods for solving the nonlinear inverse problems (synthesis problems) for optimizing th...A brief review of the works of the author and his co-authors on the application of nonlinear analysis, numerical and analytical methods for solving the nonlinear inverse problems (synthesis problems) for optimizing the different types of radiating systems, is presented in the paper. The synthesis problems are formulated in variational statements and further they are reduced to research and numerical solution of nonlinear integral equations of Hammerstein type. The existence theorems are proof, the investigation methods of nonuniqueness problem of solutions and numerical algorithms of finding the optimal solutions are proved.展开更多
In this paper, H∞ optimal model reduction for singular fast subsystems will be inves-tigated. First, error system is established to measure the error magnitude between the original andreduced systems, and it is demon...In this paper, H∞ optimal model reduction for singular fast subsystems will be inves-tigated. First, error system is established to measure the error magnitude between the original andreduced systems, and it is demonstrated that the new feature for model reduction of singular systemsis to make H∞ norm of the error system finite and minimal. The necessary and su?cient conditionis derived for the existence of the H∞ suboptimal model reduction problem. Next, we give an exactand practicable algorithm to get the parameters of the reduced subsystems by applying the matrixtheory. Meanwhile, the reduced system may be also impulsive. The advantages of the proposedalgorithm are that it is more ?exible in a straight-forward way without much extra computation, andthe order of the reduced systems is as minimal as possible. Finally, one illustrative example is givento illustrate the e?ectiveness of the proposed model reduction approach.展开更多
Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality ...Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality conditions for the Neumann problem with the quadratic performance functional are derived.展开更多
In this paper, we study the existence of solutions for 2l order (n × n) cooperative systems governed by Dirichlet and Neumann problems involving hyperbolic operators with an infinite number of variables and with ...In this paper, we study the existence of solutions for 2l order (n × n) cooperative systems governed by Dirichlet and Neumann problems involving hyperbolic operators with an infinite number of variables and with variable coefficients. The necessary and sufficient conditions for optimality of the distributed control with constraints are obtained and the set of inequalities that defining the optimal control of these systems are also obtained.展开更多
At present, mud pulse transmission systems are widely used in downhole data transmission. But the systems are very low in transmission efficiency, only 5-10 bits/s, with very large anti-inter-symbol-interference (ISI)...At present, mud pulse transmission systems are widely used in downhole data transmission. But the systems are very low in transmission efficiency, only 5-10 bits/s, with very large anti-inter-symbol-interference (ISI). It cannot meet high requirements for high-speed transmission of modern logging system. The development of communication technology has laid some foundation for this requirement. For this purpose, the Orthogonal Frequency Division Multiplexing (OFDM) Wireless Downhole Transmission Systems are proposed for the first time because of their high transmission rate, anti-inter-symbol-interference (ISI), and high spectral efficiency, etc. Due to non-linear power amplifier (PA) of logging systems with limited dynamic range, the drawbacks of high peak-average power ratio (PAPR) may outweigh all the potential benefits of OFDM wireless downhole transmission systems. Selective mapping (SLM) method can reduce the PAPR of OFDM logging signals without distortion. But at the receiver, the conventional SLM method needs exact bits of side information (SI) to recover the data signal. The probability of erroneous SI detection has a significant influence on the error performance of the system. And individual transmissions of SI result in the reduction of bandwidth efficiency. To restore the exact data signal, our scheme codes the SI bits by linear block codes (LBC), and is easily decoded by syndrome decoding. And then the coding SI bits are superimposed onto the logging signals to omit SI bits transmission. The theory and simulation results show that the proposed method has better performance than the conventional one. Accordingly, the OFDM wireless downhole transmission systems can tackle the high PAPR problem, and highten the transmission rate of logging signals.展开更多
The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterpris...The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterprise, and are subject to completely different policies designated by the government. Investigations of their daily living lead to the conclusion that the “New Unemployed” has gone through a “system withdrawal” process. They are now facing an environment of “system vacuum” that none of other unemployed groups has ever encountered before. The author emphasizes in the paper a strategic employment principle of “For Future Generations” so that focused attention and care can be provided and this toughest challenge in China can be dealt with.展开更多
We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single ...We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem.展开更多
The internal energy U of the real, neutral-gas particles of total mass M in the volume V can have positive and negative values, whose regions are identified in the state chart of the gas. Depending on the relations am...The internal energy U of the real, neutral-gas particles of total mass M in the volume V can have positive and negative values, whose regions are identified in the state chart of the gas. Depending on the relations among gas temperature T, pressure p and mass-specific volume v=V/M, the mass exists as a uniform gas of freely-moving particles having positive values U or as more or less structured matter with negative values U. In the regions U>0?above the critical point [Tc , pc , vc] it holds that p(T,v)>pc and v>vc, and below the critical point it holds that p(T,v)c and v>vv , where vv is the mass-specific volume of saturated vapor. In the adjacent regions with negative internal energy values Uc is the line of equal positive and negative energy contributions and thus represents a line of vanishing internal energy ?U=0. At this level along the critical isochor the ever present microscopic fluctuations in energy and density become macroscopic fluctuations as the pressure decreases on approaching the critical point;these are to be observed in experiments on the critical opalescence. Crossing the isochor vc from U>0 to UΔU>0 happens without any discontinuity. The saturation line vv also separates the regions between U>0 and U , but does not represent a line U=0. The internal-energy values of saturated vapor Uv and condensate Ui can be determined absolutely as functions of vapor pressure p and densities (M/V)v and (M/V)i , repectively, yielding the results Uiv, U=Ui+Uvc and U=Ui=Uv=0 at the critical point. Crossing the line Vv from U=Uv>0 to U=Uv+UiΔU=-Ui>0 to be removed from the particle system. The thermodynamic and quantum-mechanical formulations of the internal energy of a particle system only agree if both the macroscopic and microscopic energy scales have the same absolute energy reference value 0. Arguments for the energy reference value in the state of transition from bound to freely- moving particles in macroscopic classical and microscopic quantum particle systems are discussed.展开更多
Objectives: To evaluate the various scoring systems, APACHE II, SOFA, SAPS II and MPM for the prediction of prognosis of the obstetric critically ill patients admitted in a well supported ICU unit. Material and method...Objectives: To evaluate the various scoring systems, APACHE II, SOFA, SAPS II and MPM for the prediction of prognosis of the obstetric critically ill patients admitted in a well supported ICU unit. Material and methods: A prospective, observational study was conducted among all the obstetric patients admitted to the ICU between October 2011 and December 2012, during a period of 15 months. The data collected were of three categories: demographic, obstetric and ICU related. Results and Analysis: The patients admitted in the postpartum period (n = 28, 53.84%) were more than the antenatal admissions (n = 24, 46.16%). 32.69% of admissions were in the third trimester. The most common mode of delivery was emergency caesarean section (n = 27/40, 67.5%). Total caesarean deliveries were 35/40 = 87.5% in ICU patients. The mortality prediction scores were calculated for 41 patients only as acid blood gas analysis was not available for the rest. Patients required ventilation—51.92%, hemodialysis—19.23%, inotropic support—38.46%, blood transfusion—50%. Analysis of the statistical data for ICU parameters has shown that hospital stay (p = 0.011) and ventilation days (p = 0.014) are significant predictors of maternal outcome. Age (p = 0.789), ICU stay (p = 0.701) and RRT (p = 0.632) are not significant. Among the obstetric ICU admissions, hypertensive disorders of pregnancy (30.76%) was the predominant cause followed by obstetric haemorrhage (23.07%). Discussion: HELLP syndrome and eclampsia (n = 4, 57%) were the major causes of maternal deaths with anaesthetic mishaps accounting for 29% (n = 2). One (14%) death was due to Eisenmenger’s syndrome. In one case of H1N1 admitted with ARDS, caesarean section was done in MICU for worsening respiratory distress. The maternal mortality in this series of cases was 7/52 = 13.46%, excluding the unavoidable cases of maternal death (3 cases brain dead at admission and one cardiac arrest in emergency room), our maternal mortality rate is 3/48 = 6.25%. The predicted mortality as measured by all scoring systems (for 41 patients) was between 17% and 30%. The observed mortality was around 17%. Hence a reduction in mortality of 40% has been achieved due to intensive care. Conclusions: Leading cause of maternal mortality was HELLP syndrome. Hypertensive disorders of pregnancy were the most common cause of admission to ICU. In this study, all the scores were equally significant in predicting maternal mortality. Amongst the interventions done for these patients mechanical ventilation seems to have an influence on the overall outcome.展开更多
德国Wibu-Systems专业致力于软件保护,并将在CeBIT asia 4号厅C19/14展位中展示其专业的Wibu-Key和CodeMeter软件保护方案。Wibu-Systems在今年三月发布的CodeMeter ExpressCard(tm)模块标志了其在该领域的领导地位。新的ExpressCard...德国Wibu-Systems专业致力于软件保护,并将在CeBIT asia 4号厅C19/14展位中展示其专业的Wibu-Key和CodeMeter软件保护方案。Wibu-Systems在今年三月发布的CodeMeter ExpressCard(tm)模块标志了其在该领域的领导地位。新的ExpressCard技术使CodeMeter在一个小小的移动设备中提供安全的数字版权管理,并附加了10G或更大的大容量存储空间。展开更多
If Goldbach’s conjecture is true, then for each prime number p there is at least one pair of primes symmetric with respect to p and whose sum is 2p. In the multiplicative number theory, covering the positive integers...If Goldbach’s conjecture is true, then for each prime number p there is at least one pair of primes symmetric with respect to p and whose sum is 2p. In the multiplicative number theory, covering the positive integers with primes, during the prime factorization, may be viewed as being the outcome of a parallel system which functions properly if and only if Euler’s formula of the product of the reciprocals of the primes is true. An exact formula for the number of primes less than or equal to an arbitrary bound is given. This formula may be implemented using Wolfram’s computer package Mathematica.展开更多
E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a mo...E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a modern structured MOODLE interactive course, designed for the needs of the laboratory course “Automotive Systems”. The study concerns Greek secondary vocational education pupils aged 18 and vocational training adult students aged 20 to 50 years. The multistage, equal size simple random cluster sample was used as a sampling method. Pupils and adult students of each cluster completed structured 10-question questionnaires both before and after attending the course. A total of 120 questionnaires were collected. In general, our findings disclosed that the majority of pupils and adult students had significantly improved their knowledge and skills from using MOODLE. They reported strengthening conventional teaching, using the new MOODLE technology. The satisfaction indices improved quite, with the differences in their mean values being statistically significant.展开更多
In a global environment where energy and labor are becoming increasingly expensive, continuous mining systems such as In-Pit Crushing and Conveying(IPCC) systems have been advanced as offering a real alternative to co...In a global environment where energy and labor are becoming increasingly expensive, continuous mining systems such as In-Pit Crushing and Conveying(IPCC) systems have been advanced as offering a real alternative to conventional truck haulage systems. The implementation of IPCC systems in hard rock operations in open pit mines however requires different and more comprehensive planning approaches in order to adequately reflect the practical aspects associated with these. This paper investigates the impact that these approaches may have on the implementation of IPCC systems on a basic metalliferous deposit amenable to open pit exploitation. A strategic life of mine plan to provide numerous economic indicators for each approach is analyzed and compared to traditional truck haulage systems. The mine planning and evaluation process highlights the increased overall resource recovery that may accompany the use of IPCC systems. This investigation also provides insights into the issues associated with IPCC and the scale and type of operation and orebody that is likely to provide a feasible alternative to truck haulage.展开更多
Visual servoing is an active and popular area of research among roboticists.Eventhough visual servoing techniques enhance the perfomance,the associated systems still use traditional methods for their input control.Man...Visual servoing is an active and popular area of research among roboticists.Eventhough visual servoing techniques enhance the perfomance,the associated systems still use traditional methods for their input control.Many research activities and applications have been carried out to implement effective and precise controlling of bilateral systems.This paper presents a 3D spresctroscope-based control technique for bilateral systems.The effectiveness of the available master side designs are evaluated against gesture-based techniques.Joystick control,Electromyography(EMG),Voice control,Haptic control,Exoskeleton control,Gesture and Brain Control Interface(BCI)are identified in the litreature as available bilateral inputs.In the present technnique,Leap Motion Controller(LMC)has been introduced(LMC)to extract the human hand gestures and their parameters.Then these parameters are convereted into respective joint sapce angles using the presented mathematical model.The mathematical models for fingertip mapping,inverse kinematics,dynamics and trajectory generation are implemented and studied.Wolfman Mathematica 10 and MATLAB simulation framework are used to validate the mathematical models,simulations and developed control algorithms.The developed system has sucesfully imitated the fingertip motion.In particular,the system has been able to imitate the figretip motion with a deviation of 6.7%in X axis,5.5%in Y axis and7.9%in Z axis with respect to the expected position.展开更多
Pharmacokinetic models are mathematical models which provide insights into the interaction of chemicals with biological processes. During recent decades, these models have become central of attention in industry that ...Pharmacokinetic models are mathematical models which provide insights into the interaction of chemicals with biological processes. During recent decades, these models have become central of attention in industry that caused to do a lot of efforts to make them more accurate. Current work studies the process of drug and nanoparticle (NPs) distribution throughout the body which consists of a system of ordinary differential equations. We use a tri-compartmental model to study the perfusion of NPs in tissues and a six-compartmental model to study drug distribution in different body organs. We have performed global sensitivity analysis by LHS Monte Carlo method using PRCC. We identify the key parameters that contribute most significantly to the absorption and distribution of drugs and NPs in different organs in body.展开更多
文摘The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications.
文摘A transformation of the electron states—say those enclosed in a potential box—into the de Broglie waves done in the paper, enabled us to calculate the energy change between two quantum levels as a function of the specific heat and difference of the temperature between the states. In consequence, the energy difference and that of entropy between the levels could be examined in terms of the appropriate classical parameters. In the next step, the time interval necessary for the electron transition between the levels could be associated with the classical electrodynamical parameters like the electric resistance and capacitance connected with the temporary formation of the electric cell in course of the transition. The parameters characterizing the mechanical inertia of the electron were next used as a check of the electrodynamical formulae referring to transition.
基金supported by the National Natural Science Foundation of China (Nos. 41806073, 41530963)the Natural Science Foundation of Shandong Province (No. ZR 2017BD014)+1 种基金the Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals, Shandong University of Science and Technology (No. DMSM 2017042)the Fundamental Research Funds for the Central Universities (Nos. 201964016, 201851023)
文摘Many evidences for gas hydrate bearing sediments had been found in the continental slope of the East China Sea,such as bottom simulating reflections(BSRs),undersea gas springs,pyrite associated with methane leakage,mud diapirs/mud volcanos,bottom-water methane anomalies and so on.In this study,six key stratigraphic interfaces including T_0(seafloor),T_1(LGM,23 kyr B.P.),T_2(2.58 Myr),T_3(5.33 Myr),T_4(11.02 Myr)and T_5(16.12 Myr)were identified,and then five third-order sequences of SQIII1 to SQIII5 were divided.However,T5 in southern continental slope is not found,which shows that the middle-northern Okinawa Trough had begun to rift in the early Miocene,earlier than the southern segment.Four system tracts including lowstand systems tract(LST),transgressive systems tract(TST),highstand systems tract(HST)and falling stage systems tract(FSST)are further divided.The marine erosion interface of 11.02 Myr and regressive unconformity interface of 23 kyr B.P.indicate two large-scale sea level drop events in the research area.Seven typical seismic facies identified in the continental slope are continental shelf-edge deltas,littoral fluvial-delta plains,incised channels or submarine canyons,slope fans,submarine fans or coastal sandbars,littoral-neritic finegrained sediments,mud volcanos and some other geological bodies respectively.The minimum water depth for hydrate occurrence in the Okinawa Trough is 630 m,and the thickness of gas hydrate stability zone in continental slope is between 0 and 590 m.The calculated bottom boundary of hydrate stability zone is slightly deeper than BSRs on the seismic sections.The re-depositional turbidite sand bodies,such as canyon channels,slope fans and submarine fans developed in Quaternary strata,are the predominant hydrate reservoirs.According to developing process,the dynamic accumulation of hydrate systems can be divided into three evolutionary stages including canyon erosion and hydrate stability zone migration stage,sediments destabilizing and methane leakage stage,and channel filling and hydrate re-occurrence stage.
文摘Safety assessment of genetically modified organisms (GMOs) is a contentious topic. Proponents of GMOs assert that GMOs are safe since the FDA’s policy of substantial equivalence considers GMOs “equivalent” to their non-GMO counterparts, and argue that genetic modification (GM) is simply an extension of a “natural” process of plant breeding, a form of “genetic modification”, though done over longer time scales. Anti-GMO activists counter that GMOs are unsafe since substantial equivalence is unscientific and outdated since it originates in the 1970s to assess safety of medical devices, which are not comparable to the complexity of biological systems, and contend that targeted GM is not plant breeding. The heart of the debate appears to be on the methodology used to determine criteria for substantial equivalence. Systems biology, which aims to understand complexity of the whole organism, as a system, rather than just studying its parts in a reductionist manner, may provide a framework to determine appropriate criteria, as it recognizes that GM, small or large, may affect emergent properties of the whole system. Herein, a promising computational systems biology method couples known perturbations on five biomolecules caused by the CP4 EPSPS GM of Glycine max L. (soybean), with an integrative model of C1 metabolism and oxidative stress (two molecular systems critical to plant function). The results predict significant accumulation of formaldehyde and concomitant depletion of glutathione in the GMO, suggesting how a “small” and single GM creates “large” and systemic perturbations to molecular systems equilibria. Regulatory agencies, currently reviewing rules for GMO safety, may wish to adopt a systems biology approach using a combination of in silico, computational methods used herein, and subsequent targeted experimental in vitro and in vivo designs, to develop a systems understanding of “equivalence” using biomarkers, such as formaldehyde and glutathione, which predict metabolic disruptions, towards modernizing the safety assessment of GMOs.
文摘This paper examines how cybersecurity is developing and how it relates to more conventional information security. Although information security and cyber security are sometimes used synonymously, this study contends that they are not the same. The concept of cyber security is explored, which goes beyond protecting information resources to include a wider variety of assets, including people [1]. Protecting information assets is the main goal of traditional information security, with consideration to the human element and how people fit into the security process. On the other hand, cyber security adds a new level of complexity, as people might unintentionally contribute to or become targets of cyberattacks. This aspect presents moral questions since it is becoming more widely accepted that society has a duty to protect weaker members of society, including children [1]. The study emphasizes how important cyber security is on a larger scale, with many countries creating plans and laws to counteract cyberattacks. Nevertheless, a lot of these sources frequently neglect to define the differences or the relationship between information security and cyber security [1]. The paper focus on differentiating between cybersecurity and information security on a larger scale. The study also highlights other areas of cybersecurity which includes defending people, social norms, and vital infrastructure from threats that arise from online in addition to information and technology protection. It contends that ethical issues and the human factor are becoming more and more important in protecting assets in the digital age, and that cyber security is a paradigm shift in this regard [1].
文摘A brief review of the works of the author and his co-authors on the application of nonlinear analysis, numerical and analytical methods for solving the nonlinear inverse problems (synthesis problems) for optimizing the different types of radiating systems, is presented in the paper. The synthesis problems are formulated in variational statements and further they are reduced to research and numerical solution of nonlinear integral equations of Hammerstein type. The existence theorems are proof, the investigation methods of nonuniqueness problem of solutions and numerical algorithms of finding the optimal solutions are proved.
文摘In this paper, H∞ optimal model reduction for singular fast subsystems will be inves-tigated. First, error system is established to measure the error magnitude between the original andreduced systems, and it is demonstrated that the new feature for model reduction of singular systemsis to make H∞ norm of the error system finite and minimal. The necessary and su?cient conditionis derived for the existence of the H∞ suboptimal model reduction problem. Next, we give an exactand practicable algorithm to get the parameters of the reduced subsystems by applying the matrixtheory. Meanwhile, the reduced system may be also impulsive. The advantages of the proposedalgorithm are that it is more ?exible in a straight-forward way without much extra computation, andthe order of the reduced systems is as minimal as possible. Finally, one illustrative example is givento illustrate the e?ectiveness of the proposed model reduction approach.
文摘Various optimal boundary control problems for linear infinite order distributed hyperbolic systems involving constant time lags are considered. Constraints on controls are imposed. Necessary and sufficient optimality conditions for the Neumann problem with the quadratic performance functional are derived.
文摘In this paper, we study the existence of solutions for 2l order (n × n) cooperative systems governed by Dirichlet and Neumann problems involving hyperbolic operators with an infinite number of variables and with variable coefficients. The necessary and sufficient conditions for optimality of the distributed control with constraints are obtained and the set of inequalities that defining the optimal control of these systems are also obtained.
文摘At present, mud pulse transmission systems are widely used in downhole data transmission. But the systems are very low in transmission efficiency, only 5-10 bits/s, with very large anti-inter-symbol-interference (ISI). It cannot meet high requirements for high-speed transmission of modern logging system. The development of communication technology has laid some foundation for this requirement. For this purpose, the Orthogonal Frequency Division Multiplexing (OFDM) Wireless Downhole Transmission Systems are proposed for the first time because of their high transmission rate, anti-inter-symbol-interference (ISI), and high spectral efficiency, etc. Due to non-linear power amplifier (PA) of logging systems with limited dynamic range, the drawbacks of high peak-average power ratio (PAPR) may outweigh all the potential benefits of OFDM wireless downhole transmission systems. Selective mapping (SLM) method can reduce the PAPR of OFDM logging signals without distortion. But at the receiver, the conventional SLM method needs exact bits of side information (SI) to recover the data signal. The probability of erroneous SI detection has a significant influence on the error performance of the system. And individual transmissions of SI result in the reduction of bandwidth efficiency. To restore the exact data signal, our scheme codes the SI bits by linear block codes (LBC), and is easily decoded by syndrome decoding. And then the coding SI bits are superimposed onto the logging signals to omit SI bits transmission. The theory and simulation results show that the proposed method has better performance than the conventional one. Accordingly, the OFDM wireless downhole transmission systems can tackle the high PAPR problem, and highten the transmission rate of logging signals.
文摘The “New Unemployed” consists of young people with low education in the Chinese cities. They differ from the cohorts of their parents because they have no work experiences in any state- or collective-owned enterprise, and are subject to completely different policies designated by the government. Investigations of their daily living lead to the conclusion that the “New Unemployed” has gone through a “system withdrawal” process. They are now facing an environment of “system vacuum” that none of other unemployed groups has ever encountered before. The author emphasizes in the paper a strategic employment principle of “For Future Generations” so that focused attention and care can be provided and this toughest challenge in China can be dealt with.
基金supported in part by the Japan Ministry of Education,Sciences and Culture under Grants-in-Aid for Scientific Research(C)(21560471)the Green Industry Leading Program of Hubei University of Technology(CPYF2017003)the National Natural Science Foundation of China(1160147411461082)
文摘We consider quadratic stabilization for a class of switched systems which are composed of a finite set of continuoustime linear subsystems with norm bounded uncertainties. Under the assumption that there is no single quadratically stable subsystem, if a convex combination of subsystems is quadratically stable, then we propose a state-dependent switching law, based on the convex combination of subsystems, such that the entire switched linear system is quadratically stable. When the state information is not available, we extend the discussion to designing an outputdependent switching law by constructing a robust Luenberger observer for each subsystem.
文摘The internal energy U of the real, neutral-gas particles of total mass M in the volume V can have positive and negative values, whose regions are identified in the state chart of the gas. Depending on the relations among gas temperature T, pressure p and mass-specific volume v=V/M, the mass exists as a uniform gas of freely-moving particles having positive values U or as more or less structured matter with negative values U. In the regions U>0?above the critical point [Tc , pc , vc] it holds that p(T,v)>pc and v>vc, and below the critical point it holds that p(T,v)c and v>vv , where vv is the mass-specific volume of saturated vapor. In the adjacent regions with negative internal energy values Uc is the line of equal positive and negative energy contributions and thus represents a line of vanishing internal energy ?U=0. At this level along the critical isochor the ever present microscopic fluctuations in energy and density become macroscopic fluctuations as the pressure decreases on approaching the critical point;these are to be observed in experiments on the critical opalescence. Crossing the isochor vc from U>0 to UΔU>0 happens without any discontinuity. The saturation line vv also separates the regions between U>0 and U , but does not represent a line U=0. The internal-energy values of saturated vapor Uv and condensate Ui can be determined absolutely as functions of vapor pressure p and densities (M/V)v and (M/V)i , repectively, yielding the results Uiv, U=Ui+Uvc and U=Ui=Uv=0 at the critical point. Crossing the line Vv from U=Uv>0 to U=Uv+UiΔU=-Ui>0 to be removed from the particle system. The thermodynamic and quantum-mechanical formulations of the internal energy of a particle system only agree if both the macroscopic and microscopic energy scales have the same absolute energy reference value 0. Arguments for the energy reference value in the state of transition from bound to freely- moving particles in macroscopic classical and microscopic quantum particle systems are discussed.
文摘Objectives: To evaluate the various scoring systems, APACHE II, SOFA, SAPS II and MPM for the prediction of prognosis of the obstetric critically ill patients admitted in a well supported ICU unit. Material and methods: A prospective, observational study was conducted among all the obstetric patients admitted to the ICU between October 2011 and December 2012, during a period of 15 months. The data collected were of three categories: demographic, obstetric and ICU related. Results and Analysis: The patients admitted in the postpartum period (n = 28, 53.84%) were more than the antenatal admissions (n = 24, 46.16%). 32.69% of admissions were in the third trimester. The most common mode of delivery was emergency caesarean section (n = 27/40, 67.5%). Total caesarean deliveries were 35/40 = 87.5% in ICU patients. The mortality prediction scores were calculated for 41 patients only as acid blood gas analysis was not available for the rest. Patients required ventilation—51.92%, hemodialysis—19.23%, inotropic support—38.46%, blood transfusion—50%. Analysis of the statistical data for ICU parameters has shown that hospital stay (p = 0.011) and ventilation days (p = 0.014) are significant predictors of maternal outcome. Age (p = 0.789), ICU stay (p = 0.701) and RRT (p = 0.632) are not significant. Among the obstetric ICU admissions, hypertensive disorders of pregnancy (30.76%) was the predominant cause followed by obstetric haemorrhage (23.07%). Discussion: HELLP syndrome and eclampsia (n = 4, 57%) were the major causes of maternal deaths with anaesthetic mishaps accounting for 29% (n = 2). One (14%) death was due to Eisenmenger’s syndrome. In one case of H1N1 admitted with ARDS, caesarean section was done in MICU for worsening respiratory distress. The maternal mortality in this series of cases was 7/52 = 13.46%, excluding the unavoidable cases of maternal death (3 cases brain dead at admission and one cardiac arrest in emergency room), our maternal mortality rate is 3/48 = 6.25%. The predicted mortality as measured by all scoring systems (for 41 patients) was between 17% and 30%. The observed mortality was around 17%. Hence a reduction in mortality of 40% has been achieved due to intensive care. Conclusions: Leading cause of maternal mortality was HELLP syndrome. Hypertensive disorders of pregnancy were the most common cause of admission to ICU. In this study, all the scores were equally significant in predicting maternal mortality. Amongst the interventions done for these patients mechanical ventilation seems to have an influence on the overall outcome.
文摘德国Wibu-Systems专业致力于软件保护,并将在CeBIT asia 4号厅C19/14展位中展示其专业的Wibu-Key和CodeMeter软件保护方案。Wibu-Systems在今年三月发布的CodeMeter ExpressCard(tm)模块标志了其在该领域的领导地位。新的ExpressCard技术使CodeMeter在一个小小的移动设备中提供安全的数字版权管理,并附加了10G或更大的大容量存储空间。
文摘If Goldbach’s conjecture is true, then for each prime number p there is at least one pair of primes symmetric with respect to p and whose sum is 2p. In the multiplicative number theory, covering the positive integers with primes, during the prime factorization, may be viewed as being the outcome of a parallel system which functions properly if and only if Euler’s formula of the product of the reciprocals of the primes is true. An exact formula for the number of primes less than or equal to an arbitrary bound is given. This formula may be implemented using Wolfram’s computer package Mathematica.
文摘E-learning platforms support education systems worldwide, transferring theoretical knowledge as well as soft skills. In the present study high-school pupils’, and adult students’ opinions were evaluated through a modern structured MOODLE interactive course, designed for the needs of the laboratory course “Automotive Systems”. The study concerns Greek secondary vocational education pupils aged 18 and vocational training adult students aged 20 to 50 years. The multistage, equal size simple random cluster sample was used as a sampling method. Pupils and adult students of each cluster completed structured 10-question questionnaires both before and after attending the course. A total of 120 questionnaires were collected. In general, our findings disclosed that the majority of pupils and adult students had significantly improved their knowledge and skills from using MOODLE. They reported strengthening conventional teaching, using the new MOODLE technology. The satisfaction indices improved quite, with the differences in their mean values being statistically significant.
文摘In a global environment where energy and labor are becoming increasingly expensive, continuous mining systems such as In-Pit Crushing and Conveying(IPCC) systems have been advanced as offering a real alternative to conventional truck haulage systems. The implementation of IPCC systems in hard rock operations in open pit mines however requires different and more comprehensive planning approaches in order to adequately reflect the practical aspects associated with these. This paper investigates the impact that these approaches may have on the implementation of IPCC systems on a basic metalliferous deposit amenable to open pit exploitation. A strategic life of mine plan to provide numerous economic indicators for each approach is analyzed and compared to traditional truck haulage systems. The mine planning and evaluation process highlights the increased overall resource recovery that may accompany the use of IPCC systems. This investigation also provides insights into the issues associated with IPCC and the scale and type of operation and orebody that is likely to provide a feasible alternative to truck haulage.
文摘Visual servoing is an active and popular area of research among roboticists.Eventhough visual servoing techniques enhance the perfomance,the associated systems still use traditional methods for their input control.Many research activities and applications have been carried out to implement effective and precise controlling of bilateral systems.This paper presents a 3D spresctroscope-based control technique for bilateral systems.The effectiveness of the available master side designs are evaluated against gesture-based techniques.Joystick control,Electromyography(EMG),Voice control,Haptic control,Exoskeleton control,Gesture and Brain Control Interface(BCI)are identified in the litreature as available bilateral inputs.In the present technnique,Leap Motion Controller(LMC)has been introduced(LMC)to extract the human hand gestures and their parameters.Then these parameters are convereted into respective joint sapce angles using the presented mathematical model.The mathematical models for fingertip mapping,inverse kinematics,dynamics and trajectory generation are implemented and studied.Wolfman Mathematica 10 and MATLAB simulation framework are used to validate the mathematical models,simulations and developed control algorithms.The developed system has sucesfully imitated the fingertip motion.In particular,the system has been able to imitate the figretip motion with a deviation of 6.7%in X axis,5.5%in Y axis and7.9%in Z axis with respect to the expected position.
文摘Pharmacokinetic models are mathematical models which provide insights into the interaction of chemicals with biological processes. During recent decades, these models have become central of attention in industry that caused to do a lot of efforts to make them more accurate. Current work studies the process of drug and nanoparticle (NPs) distribution throughout the body which consists of a system of ordinary differential equations. We use a tri-compartmental model to study the perfusion of NPs in tissues and a six-compartmental model to study drug distribution in different body organs. We have performed global sensitivity analysis by LHS Monte Carlo method using PRCC. We identify the key parameters that contribute most significantly to the absorption and distribution of drugs and NPs in different organs in body.