Research on Embedding Capacity and Efficiency of Information Hiding Based on Digital Images

Generally speaking, being an efficient information hiding scheme, what we want to achieve is high embedding capacity of the cover image and high visual quality of the stego image, high visual quality is also called embedding efficiency. This paper mainly studies on the information hiding technology based on gray-scale digital images and especially considers the improvement of embedding capacity and embedding efficiency. For the purpose of that, two algorithms for information hiding were proposed, one is called high capacity of information hiding algorithm (HCIH for short), which achieves high embedding rate, and the other is called high quality of information hiding algorithm (HQIH for short), which realizes high embedding efficiency. The simulation experiments show that our proposed algorithms achieve better performance.

Effects of evacuation assistant's leading behavior on the evacuation efficiency: Information transmission approach

Evacuation assistants are expected to spread the escape route information and lead evacuees toward the exit as quickly as possible. Their leading behavior influences the evacuees＇ movement directly, which is confirmed to be a decisive factor of the evacuation efficiency. The transmission process of escape information and its function on the evacuees＇ movement are accurately presented by the proposed extended dynamic communication field model. For evacuation assistants and eevacuees, their sensitivity parameter of static floor field（SFF）, kL S, and kS, are fully discussed. The simulation results e indicate that the appropriate kL Sis associated with the maximum kSof evacuees. The optimal combinations of kL Sand e kSwere found to reach the highest evacuation efficiency. There also exists an optimal value for evacuation assistants＇ information transmission radius.

The Information Efficiency and Functionality Efficiency of Stock Markets

The efficiency of a stock market is principally measured by its information efficiency and functionality efficiency. Both metrics are closdy related to the information of stock markets. However, there is no uniform definition of information in the economy field since researchers may have various opinions on the information of stock markets. In this research, a comparatively strict definition of information in sense of economy is presented. Based on this definition, the optimal conditions to reach the maximum information efficiency and functionality efficiency of stock markets are derived. The conclusion is, only when the market＇s operation and information transmission mechanisms are fully effective, its information completeness degree is optimal, all investors take optimal equilibrium actions, and the information efficiency and functionality efficiency of stock markets will be optimal. Based on the conclusions, the information efficiency and functionality efficiency of reality stock markets in China are studied and the corresponding supervision countermeasures are suggested.

Temperature Effects on Information Capacity and Energy Efficiency of Hodgkin-Huxley Neuron

Recent experimental and theoretical studies show that energy efficiency, which measures the amount of infor- mation processed by a neuron with per unit of energy consumption, plays an important role in the evolution of neural systems. Here we calculate the information rates and energy efficieneies of the Hodgkin-Huxley （HH） neuron model at different temperatures in a noisy environment. It is found that both the information rate and energy efficiency are maximized by certain temperatures. Though the information rate and energy efficiency cannot be maximized simultaneously, the neuron holds a high information processing capacity at the tempera- ture corresponding to the maximal energy efficiency. Our results support the idea that the energy efficiency is a selective pressure that influences the evolution of nervous systems.

Optimal Size for Maximal Energy Efficiency in Information Processing of Biological Systems Due to Bistability

Energy efficiency is closely related to the evolution of biological systems and is important to their information processing. In this work, we calculate the excitation probability of a simple model of a bistable biological unit in response to pulsatile inputs, and its spontaneous excitation rate due to noise perturbation. Then we analytically calculate the mutual information, energy cost, and energy efficiency of an array of these bistable units. We find that the optimal number of units could maximize this array＇s energy efficiency in encoding pulse inputs, which depends on the fixed energy cost. We conclude that demand for energy efficiency in biological systems may strongly influence the size of these systems under the pressure of natural selection.

Earnings information quality, debt maturity structure and investment efficiency

This paper studies the effect of earnings information quality and debt maturity structure and their interaction on investment efficiency. The results show that companies with higher earnings information have higher investment efficiency, and the quality of earnings information has increased investment efficiency by reducing the lack of investment and suppressing overinvestment. The companies with higher short-term debt ratio show higher investment efficiency. The results show that there is a certain substitution effect between the effect of earnings information quality and the maturity strueture of debt on the efficiency of investment.

The Information Efficiency of QFII's Investment in China's Capital Market

This paper takes stock price synchronization and price delay as indicators of information efficiency, and uses mixed cross-sectional data of listed companies into which Qualified Foreign Institutional Investors(QFII) have made investments, to study the impact of QFII's investment behaviors on the information efficiency of China's stock market. The results show that QFII's investments can improve the information efficiency of China's stock market, but its impact is varied. The impact of QFII's investments on market information efficiency is more significant in bear markets than in bull markets, the impact on private enterprises is more significant than on state-owned enterprises, and the impact on Small and Medium Enterprises(SME) market is more significant than in main board market. Further research also finds that QFII has a certain threshold effect on the information efficiency of China's stock market. This research paper provides a problem-solving perspective for China's capital markets to achieve information efficiency through opening up, and at the same time warns against financial risks.

Cross-efficiency DEA model-based evaluation of allocative efficiency of rural information resources in Jiangsu Province, China

Purpose: This paper aims to compare and rank the allocative efficiency of information resources in rural areas by taking 13 rural areas in Jiangsu Province, China as the research sample.Design/methodology/approach: We designed input and output indicators for allocation of rural information resources and conducted the quantitative evaluation of allocative efficiency of rural information resources based on cross-efficiency model in combination with the classical CCR model in data envelopment analysis(DEA).Findings: Cross-efficiency DEA model can be used for our research with the objective to evaluate quantitatively and objectively whether the allocation of information resources in various rural areas is reasonable and whether the output is commensurate with the input.Research limitations: We have to give up using some indicators because of limited data availability. There is a need to further improve the cross-efficiency DEA model because it cannot identify the specific factors influencing the efficiency of decision-making units(DMUs).Practical implications: The evaluation results will help us understand the present allocative efficiency levels of information resources in various rural areas so as to provide a decisionmaking basis for formulation of the policies aimed at promoting the circulation of information resources in rural areas.Originality/value: Little or no research has been published about the allocative efficiency of rural information resources. The value of this research lies in its focus on studying rural informatization from the perspective of allocative efficiency of rural information resources and in the application of cross-efficiency DEA model to evaluate allocative efficiency of rural information resources as well.

Does Margin Trading Enhance Information Efficiency of the Capital Market?——Evidence from China

On March 31,2010,China formally introduced a margin trading system,which announced that China's capital market has completed the transformation from a unilateral transaction model to a bilateral transaction model with a short-selling mechanism.However,the current development of China's margin trading and securities lending businesses is seriously unbalanced,and the scale of financing far exceeds the scale of securities lending.The short selling effect of securities lending exchanges is extremely limited,which to some extent violates the original intention of introducing the system.In order to help margin trading and securities lending to correct a healthy and sustainable development path,this article uses stock price synchronicity as a proxy indicator to measure the information efficiency of the capital market,explores the impact of the margin trading system on the information efficiency of the capital market,and study the detailed characteristics and economic consequences of the margin trading system.Aiming at this topic,this article analyzes the relationship between margin financing and securities lending and stock price synchronicity.Finally,it analyzes the influence of margin financing and securities lending system on stock price synchronicity from three dimensions of corporate governance,external supervision,and institutional environment mechanism.In terms of empirical research,this article takes advantage of the“quasi-natural experiment”provided by the gradual opening of margin trading and securities lending in China’s securities market,and selects listed companies on the Shanghai and Shenzhen stock exchanges from 2007 to 2019 as the research objects,starting from the perspective of stock price synchronicity,and passing The DID-FE model studies the impact of the margin trading and securities lending system on the information efficiency of the capital market.It uses three methods:parallel trend and dynamic testing,PSM-DID analysis,and placebo testing for robustness testing to solve the endogeneity problem of the experiment.This article also conducts deeper research on the subject based on the two dimensions of the impact mechanism of margin financing and securities lending and the size of the company,and finally discusses the economic impact of margin financing and securities lending on the level of company innovation.

Efficiency of Stock Exchange Markets in G7 Countries： Bootstrap Causality Approach

Market efficiency is based on efficient market hypothesis （EMH）. EMH claims that market totally contains the available information. In case of EMH, valid investors who take position will not gain abnormal profits. If the efficiency can not be established, that is, if markets are not efficient, investors will have the opportunity of abnormal profits. This paper investigates the causality relations to determine validity of EMH among G7 （Canada, France, Germany, Italy, Japan, United Kingdom, and United States） countries＇ stock exchange markets for the period from July 2003 to October 2014. To find out whether the variables cause each other or not provides knowledge about the market efficiency. The implication of this analysis is twofold. One implication is that if the markets are informationally efficient, the possibility of abnormal returns through arbitrage is ruled out and investors can reduce the risk of their investment for the same expected returns, if they establish portfolios that consist of both markets rather than consisting of only one market. Based on this, Hacker-Hatemi-J. bootstrap causality test that is newer and has many advantages contrary to other tests was used. Results showed that EMH is valid among each G7 countries＇ stock exchange markets. Also portfolio diversification benefits exist among these markets.

Real estate market efficiency: Evidence from Chinese cities

The price in an efficient market can adjust to new information instantaneously to eliminate any arbitrage opportunities. Such a phenomenon is not always observed in the real estate market because of its unique characteristics, which include fixed location, heterogeneity and low transaction frequency. Using housing and office market data of some major cities in China, this paper examines the return and risk characteristics in these markets and assesses market efficiency. It finds that a number of instruments, including lagged quarterly and annual excess returns and, to some extent, the measure of the deviation of price from the intrinsic value, predict future returns. Therefore, weak form and semi-strong form efficiency can both be rejected in these real estate markets. These empirical findings suggest that there is slow price adjustment in real estate markets in China, which may be attributed to inefficient information transmission systems and long searching time in the markets.

A contention-based efficient-information perception algorithm (CEiPA) for vehicular ad hoc networks

The problem of information dissemination is researched for vehicular ad-hoc networks （VANET） in this paper, and a contention-based effficient-information perception algorithm （CEiPA） is proposed. The idea of CEiPA is that beacons are delivered over VANET with limited lifetime and efficient information. CEiPA consists of two phases. The first one is initialization phase, during which the count timers Tcyce and Tlocal are set to start beacon delivery while Tcycle is also used to monitor and restart beaconing. The second one is beacon delivery phase. An elaborate distance function is employed to set contention delay for beacons of each vehicle. In this way beacons will be sent in order, which decreases the collision of beacons. Simulation results show that CEiPA enables each beacon to carry more efficient information and spread them over more vehicles with lower network overhead than the periodic beacon scheme. CEiPA is also flexible and scalable because the efficient information threshold it employs is a balance among the freshness of information, network overhead and perception area of a vehicle.

An Efficient CSI Feedback Scheme for Dual-Polarized MIMO Systems Using Layered Multi-Paths Information

Massive MIMO is one of tile enabling technologies tbr beyond 4G and 5G systems due to its ability to provide beamforming gain and reduce interference Dual-polarized antenna is widely adopted to accommodate a large number of antenna elements in limited space. However, current CSI（channel state information） feedback schemes developed in LTE for conventional MIMO systems are not efficient enough for massive MIMO systems since the overhead increases almost linearly with the number of antenna. Moreover, the codebook for massive MIMO will be huge and difficult to design with the LTE methodology. This paper proposes a novel CSI feedback scheme named layered Multi-paths Information based CSI Feedback （LMPIF）, which can achieve higher spectrum efficiency for dual-polarized antenna system with low feedback overhead. The MIMO channel is decomposed into long term components （multipath directions and amplitudes） and short term components （multipath phases）. The relationship between the two components and the optimal precoder is derived in closed form. To reduce the overhead, different granularities in feedback time have been applied for the long term components and short term components Link and system level simulation results prove that LMPIF can improve performance considerably with low CSI feedback overhead.

Energy efficiency optimization of relay-assisted D2D two-way communications with SWIPT

Aiming at the energy consumption of long-distance device-to-device(D2D) devices for two-way communications in a cellular network,this paper proposes a strategy that combines two-way relay technology(TWRT) and simultaneous wireless information and power transfer(SWIPT) technology to achieve high energy efficiency(EE) communication.The scheme first establishes a fractional programming problem to maximize EE of D2D,and transforms it into a non-fractional optimization problem that can be solved easily.Then the problem is divided into three sub-problems:power control,power splitting ratios optimization,and relay selection.In order to maximize EE of the D2D pair,the Dinkelbach iterative algorithm is used to optimize the transmitted power of two D2D devices simultaneously;the one-dimensional search algorithm is proposed to optimize power splitting ratios;an improved optimal relay selection scheme based on EE is proposed to select relay.Finally,experiments are carried out on the Matlab simulation platform.The simulation results show that the proposed algorithm has faster convergence.Compared with the one-way relay transmission and fixed relay algorithms,the proposed scheme has higher EE.

The Efficiency Control Assessment for Electronic System

The data of the analytical estimation on the efficiency of providing safety control of the radioelectronic system are given.The review is based on the investigation of the information interaction of the radio-electronic system(RS)with monitoring subsystem.The problem of optimal safety operational subsystem control of the RS and the generalized criterion for the effectiveness of decision making by the control system of the RS are formulated.Analytical expressions that allow making the choice of optimal ratio between the safe and the most effective modes of the control system operation are obtained.

Adaptive Energy-Efficient Power Allocation for DAS with Imperfect Channel State Information and Antenna Selection

Considering that perfect channel state information(CSI) is difficult to obtain in practice,energy efficiency(EE) for distributed antenna systems(DAS) based on imperfect CSI and antennas selection is investigated in Rayleigh fading channel.A novel EE that is defined as the average transmission rate divided by the total consumed power is introduced.In accordance with this definition,an adaptive power allocation(PA) scheme for DAS is proposed to maximize the EE under the maximum transmit power constraint.The solution of PA in the constrained EE optimization does exist and is unique.A practical iterative algorithm with Newton method is presented to obtain the solution of PA.The proposed scheme includes the one under perfect CSI as a special case,and it only needs large scale and statistical information.As a result,the scheme has low overhead and good robustness.The theoretical EE is also derived for performance evaluation,and simulation result shows the validity of the theoretical analysis.Moreover,EE can be enhanced by decreasing the estimation error and/or path loss exponents.

Long Window Tests of China's Stock Market Efficiency in Different Sectors around the Disclosure of Annual Report

10 stock sectors are selected in Shanghai and Shenzhen stock market’s as samples.By event study,the change of stock’s cumulative abnormal return rate around the data of annual report disclosure was analyzed among the year 2004-2008.The market reaction pattern of such kind of news was summarized in order to test the efficiency of China’s stock market and its trend before and after the comprehensive completion of the Share-trading Reform and the implementation of new Accounting Standards.The conclusion is that Chinese stock markets response more accurately to ROE and EPS;its efficiency continued to decline in 2005 and 2006,but there was a gradual increase in 2007 and in 2008;and in general the capital market do not reach the semi-strong efficiency,but the machinery industry and biopharmaceutical industry have done.

Accounting information quality,governance efficiency and capital investment choice

This paper examines the relationship between accounting information quality and capital investment choice from the perspective of accounting information's governance function.Measuring capital investment choice as the correlation of growth of operating income between company and industry,this paper investigates whether and to what extent companies focus on their core business.The results show that the higher the quality of publicly listed firms' accounting information,the stronger that correlation,particularly when the corporate governance of the listed company is poor.The findings imply that accounting information quality can thus optimize the capital investment choice,which complements and strengthens the functioning of corporate governance.Hence,regulators should pay more attention to the market's power to supervise the behavior of listed firms,improve the governance functions of accounting information and increase the efficiency of capital allocation.

Effects of real-time traffic information systems on traffic performance under different network structures

The effects of real-time traffic information system(RTTIS)on traffic performance under parallel,grid and ring networks were investigated.The simulation results show that the effects of the proportion of RTTIS usage depend on the road network structures.For traffic on a parallel network,the performance of groups with and without RTTIS level is improved when the proportion of vehicles using RTTIS is greater than 0 and less than 30%,and a proportion of RTTIS usage higher than 90%would actually deteriorate the performance.For both grid and ring networks,a higher proportion of RTTIS usage always improves the performance of groups with and without RTTIS.For all three network structures,vehicles without RTTIS benefit from some proportion of RTTIS usage in a system.