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Tailings pond plays a very important role in the construction of mine engineering. At the same time, tailings pond also produces huge pollution to the environment. If dam break occurs, it will cause loss of people and property. In this paper, a tailings pond management system based on RSCIC is studied, the monitoring content of the system is determined, the more innovative system and hardware are emphasized, the program flow chart of digital processing is put forward. Adopting scientific and effective means to manage the tailing dam automatically can not only strengthen the safety protection of the tailing dam, but also provide a certain theoretical basis for the construction of other digital tailings dam projects.

Data resources and assessment frameworks are two keys to ecosystem health assessment (EHA). Application of the land use database together with the Pressure–State–Response (PSR) model in EHA provides better precision relative to traditional data resources and assessment frameworks for EHA at the county scale. The raw data are taken from The Anlu County Annals, The Soil Records of Anlu County, and The Statistical Yearbook of National Economy in Anlu County. The spatial and attribute data are partly extracted from the database of current land use in Anlu City using the MAPGIS platform. Based on the results from principal component analysis (PCA), a total of eleven indicators were selected to build an indicator system designed to assess the ecosystem health at the county scale. According to the PSR model, the scores from three indices (press index, state index, and response index) and a comprehensive assessment index (CAI) were calculated, and an assessment map was constructed. The results from the index scores and spatial analysis display a large range for the state of ecosystem health due to the evolution of natural ecosystems and human activities at the county scale. The precision of the current land use database (scale of 1:10,000) makes it a better candidate for evaluating ecosystem health than the traditional data resources. This study also demonstrates the numerous benefits of combining land use databases with GIS functions to assess ecosystem health at the county scale.

A new Co-base superalloy 22Co–21Ni–23Fe–29Cr–2.2Nb (Co22 for short) was developed, and the influence of a trace amount of rare earth (RE) on the oxidation resistance was investigated. Isothermal oxidation behaviour of this Co-base superalloy was investigated at 1050–1250 °C in air, analyzed with scanning electronic microscopy and X-ray diffraction. The results show that oxidation mass gain of the samples with or without RE elements obeyed secondary parabolic law, and the effect of 0.03 wt.% RE on oxidation resistance is small. The oxidation rate constant of the 0.03 wt.% RE added Co22 alloy decreases by about 6.1% to 9.0% compared to that of the Co22 alloy without RE. Oxidation at 1050–1250 °C for 100 h results in the formation of MnCr 2 O 4 , Cr 2 O 3 and SiO 2 . A continuous and protective MnCr 2 O 4 spinel layer forms as outer layer. The continuous middle oxide layer is confirmed to be Cr 2 O 3 , and the innermost layer consists of discontinuous SiO 2 . The outer and middle layers strongly improve oxidation resistance and oxide layer adhesion because of their continuity and compactness, and the innermost SiO 2 layer forms a diffusion barrier to prevent further oxidation. Formation and growth mechanisms of oxide layers were also discussed.

Stable lead (Pb) isotopic fingerprints provide opportunities to trace natural and anthropogenic Pb sources in the environment. In order to evaluate Pb deposition from different sources over mountainous areas of western China, Pb isotopic compositions were characterized from modern aeolian dust in 15 snowpit samples collected from 13 typical mountain glaciers between 2008 and 2010. Most of the snowpits sampled cover more than a whole year of accumulation and overlap with each other on deposition date. Pb isotopic variability among all the samples is small, varying in the range of 18.1399-18.9199 for Pb-206/Pb-204, 15.5979-15.8743 for Pb-207/Pb-204, 38.2272-39.9453 for Pb-208/Pb-204, 1.1605-1.2009 for Pb-206/Pb-207 and 2.4433-2.5182 for Pb-208/Pb-207. Three isotopic plots of the different Pb isotope ratios (Pb-207/Pb-204 vs. Pb-206/Pb-204, Pb-208/Pb-204 vs. Pb-206/Pb-204, and Pb-208/Pb-207 vs. Pb-206/Pb-207) in all the samples show identical geographic trends, with more radiogenic in the south and less in the north. This trend is consistent with the distribution of natural dust sources and supports the interpretation of a regional/local source for insoluble particles (IP) to snow/glaciers in this region. Comparison with the Pb isotope results from potential dust sources, however, it shows that the Pb isotopic compositions of IP samples in snow samples are relatively less radiogenic. Parts of these less-radiogenic Pb isotopes are comparable with the ice core results during recent decades, which are shown to be influenced by anthropogenic sources. At sites located along the periphery of western China, the Pb isotopic compositions are much closer to anthropogenic results. Natural and anthropogenic Pb sources are roughly assessed using a simple binary model. The sites with a high anthropogenic fraction are at lower elevations and are relatively close to population centers. (C) 2013 Elsevier Ltd. All rights reserved.

The purpose of this study is to develop an assessment framework of ecological security at the watershed scale to meet the need of watershed management, and to assess ecological security using this framework in the middle and lower reaches of Hanjiang River Basin (in Hubei Province, China). The states and their changes of ecological security in the study region are investigated with the support of ERDAS and ARC/INFO platform. The results show that the ecological security index (P) values in 1995 and 2000 were 0.685 and 0.699 respectively in the study region. While in 2005 and 2010, the P values were decreased to 0.657 and 0.624. In 1995, there were 5 counties with degree II state (the poor state) of ecological security, and 14 counties with degree III state (the common state). By 2000, the amount of counties with degree II decreased to 4 counties. And the number of counties with degree II is the same as 2000 in 2005. The result of 2010 shows there were 12 countries with degree III state as well as 7 counties with degree II state. The results of our case study of the Hanjiang River Basin reflect that the ES situation is very grim in the study area. The degree of ecological security developed in this study can be used as a useful tool for watershed managers and decision-makers.

A fast-settling all-digital phase-locked loop (ADPLL) is presented in this paper. We propose two techniques for reducing the settling time of an ADPLL, i.e. the oscillator tuning word (OTW) presetting technique and counter-based mode switching controller (CB-MSC). In the first technique, the OTW is preset in process, voltage, and temperature (PVT) calibration mode (P-mode), which leads to the digitally controlled oscillator being initialized with a frequency closer to the target. In the second technique, the CB-MSC is used to shorten the mode switching time. A prototype 1.9 GHz ADPLL with a 13 MHz reference is implemented in 0.18 μm CMOS process. Measurements show that the proposed techniques reduce the settling time by about 33 %. The proposed ADPLL settles within 130 reference cycles and presents a phase noise of ?116 dBc/[email protected] MHz.

To persistently eavesdrop on the mobile devices, attackers may obtain the elevated privilege and inject malicious modules into the user devices. Unfortunately, the attackers may not be able to obtain the privilege for a long period of time since the exploitable vulnerabilities may be fixed or the malware may be removed. In this paper, we propose a new data hijacking attack for the mobile apps. By employing the proposed method, the attackers are only required to obtain the root privilege of the user devices once, and they can persistently eavesdrop without any change to the original device. Specifically, we design a new approach to construct a shadow system by hijacking user data files. In the shadow system, attackers possess the identical abilities to the victims. For instance, if a victim has logged into the email app, the attacker can also access the email server in the shadow system without authentication in a long period of time. Without reauthentication of the app, it is difficult for victims to notice the intrusion since the whole eavesdropping is performed on other devices (rather than the user devices). In our experiments, we evaluate the effectiveness of the proposed attack and the result demonstrates that even the Android apps released by the top developers cannot resist this attack. Finally, we discuss some approaches to defend the proposed attack.

Land Use/Cover Change (LUCC) has gradually became an important direction in the research of global changes. LUCC is a complex system, and entropy is a measure of the degree of disorder of a system. According to land use information entropy, this paper analyzes changes in land use from the perspective of the system. Research on the entropy of LUCC structures has a certain “guiding role” for the optimization and adjustment of regional land use structure. Based on the five periods of LUCC data from the year of 1990 to 2010, this paper focuses on analyzing three types of LUCC entropies among counties in China—namely, Shannon, Renyi, and Tsallis entropies. The findings suggest that: (1) Shannon entropy can reflect the volatility of the LUCC, that Renyi and Tsallis entropies also have this function when their parameter has a positive value, and that Renyi and Tsallis entropies can reflect the extreme case of the LUCC when their parameter has a negative value., (2) The entropy of China’s LUCC is uneven in time and space distributions, and that there is a large trend during 1990–2010, the central region generally has high entropy in space.

The concentration and size distribution of aerosol particles in the range of 0.25-32 mu m was monitored with an optical particle counter from 2009 to 2011 at the Qilian Shan Station of Glaciology and Ecologic Environment (QSS) (39.50N, 96.51E

A highly sensitive acetylcholinesterase (AChE) electrochemical biosensor for the quantitative determination of organophosphate pesticides (OPs) in vegetables and fruits based on palladium-copper nanowires (Pd-Cu NWs) was reported. AChE immobilized on the modified electrode could catalyze hydrolysis of acetylthiocholine chloride (ATCl), generating an irreversible oxidation peak. When exposed to the OPs, the activity of the AChE was inhibited and the current significantly decreased. The detection mechanism is based on the inhibition of AChE. The Pd-Cu NWs not only provide a large active surface area (0.268 ± 0.01) cm 2 for the immobilization of AChE, which was approximately 3.8 times higher than the bare glass carbon electrode, but also exhibit excellent electro-catalytic activity and remarkable electron mobility. The biosensor modified with Pd-Cu NWs displayed a good affinity to ATCl and catalyzed hydrolysis of ATCl, with a low Michaelis–Menten constant ( K M ) of 50.56 μM. Under optimized conditions, the AChE-Cs/Pd-Cu NWs/GCE biosensor detected malathion with wide linear ranges of 5–1000 ppt and 500–3000 ppb, and the low detection limit was 1.5 ppt (4.5 pM). In addition, the OPs biosensor has been applied to the analysis of malathion in commercial vegetable and fruit samples, with excellent recoveries in the range of 98.5%–113.5%. This work provides a simple, sensitive and effective platform for biosensors and exhibits future potential in practical application for the OPs assay.

This paper introduces the statistical methods and application for the quantitative analysis of a site-specific landslide risk on the north slope of Lishan Mountain which is regarded being in an active state that could become a disastrous loess landslide. Based on the theory of probability statistics (Monte Carlo statistical methods) and the slope failure mechanical model, the overall failure probability and the local failure probabilities of the Lishan landslide were calculated. The results of the failure probability and stability analysis showed that the northern slope of Lishan Mountain is highly prone to lose stability during seasonal intense rainfall, whereas it is stable but still exhibits failure probability under arid conditions. The analysis of the safety margin and local failure probability evidenced that the upper part of the slope is less stable than the lower part. Under the intense rainfall condition, the local failure probability and hazard of local unstable failure of the slope will increase. According to the calculation results, it is deduced that the landslide on the north of Lishan Mountain will be a gradual process evolving from the local slope failure to an overall unstable failure.

Time-to-Digital Converter (TDC) is a key block used as the phase/frequency detector in an All-Digital Phase-Locked Loop (ADPLL). Usually, it occupies a large proportion of ADPLL’s total power consumption up to about 30% to 40%. In this paper, the detailed power consumption of different components in the TDC is analyzed. A Power Management Block (PMB) is presented for the TDC to reduce its power consumption. A 24-bits TDC core with the proposed PMB is implemented in HJTC 0.18 μm CMOS technology. Simulation results show that up to 84% power reduction is achieved using our proposed technique.

In this paper, the effect of cyclic loading on drained residual strength of over-consolidated silty clay is examined based on the results from ring shear tests which were conducted with a sophisticated ring shear apparatus. Initially sheared to form shear zones under different pre-consolidation pressures and at different shear rates (SRs), soil samples were then tested under cyclic loading. After the cyclic loading application, the samples were re-sheared while the corresponding shear strengths were measured. The results show that the effect of cyclic loading on residual strength is noticeable. The effect is related to pre-consolidation history and SR of the soil samples. Under conditions of relatively low over-consolidation ratio (OCR), the soil samples show an increase in residual strength with decreasing SR after cyclic loading. Most of the peak strength values after cyclic loading are higher than the residual strength values obtained before cyclic loading. Two effects of cyclic loading on the residual strength are identified: (a) If OCR is less than or equal to 3.0, the residual strengths measured after cyclic loading are larger than those before cyclic loading; (b) If OCR is greater than or equal to 3.5, the residual strengths after cyclic loading tend to become lower than those in the shear tests before cyclic loading.

A low-power low-noise intermediate-frequency (IF) circuit is proposed for Gaussian frequency shift keying (GFSK) low-IF receivers. The proposed IF circuit is realized by an all-analog architecture composed of a couple of limiting amplifiers (LAs) and received signal strength indicators (RSSIs), a couple of band-pass filters (BPFs), a frequency detector (FD), a low-pass filter (LPF) and a slicer. The LA and RSSI are realized by an optimized combination of folded amplifiers and current subtractor based rectifiers to avoid the process induced depressing on accuracy. In addition, taking into account the nonlinearity and static current of rectifiers, we propose an analytical model as an accurate approximation of RSSIs' transfer character. An active-RC based GFSK demodulation scheme is proposed, and then both low power consumption and a large dynamic range are obtained. The chip is implemented with HJTC 0.18µm CMOS technology and measured under an intermediate frequency of 200kHz, a data rate of 100kb/s and a modulation index of 1. The RSSI has a dynamic range of 51dB with a logarithmic linearity error of less than ±1dB, and the slope is 23.9mV/dB. For 0.1% bit error ratio (BER), the proposed IF circuit has the minimum input signal-to-noise ratio (SNR) of 5dB and an input dynamic range of 55.4dB, whereas it can tolerate a frequency offset of -3%∼+9.5%% at 6dB input SNR. The total power consumption is 5.65∼5.89mW.

By employing a complete observation system, the underground erosion in a typical large-scale crystalline schist landslide in Japan, the Zentoku landslide, was studied. It was found that the seasonal heavy rainfall is the main factor leading to the massive underground erosion. Two types of sediment discharge of the landslide were defined. Monitored data indicated that the movement of Zentoku landslide could be affected by the underground erosion following the concentrated heavy rainfall. The influence of the underground erosion on the movement of the landslide presents different features. For the sliding block of shallow and medium depth shear zones (5–20 m), the influence of the underground erosion is most outstanding, while it is negligible for the sliding block of thick soil and rock layers (>30 m). Finally, the rainfall thresholds for the Zentoku landslide, which concern the groundwater state, underground erosion and movement of sliding blocks, were provided to further establish the warning and evacuation system.

The purpose of this study is to identify and classify the ecological risks in land consolidation, and to develop a framework of the theory and method to assess the change of ecological risk degree before and after land consolidation. Environmental impacts and ecological risks of land consolidation have recently drawn much attention, and there are two opposing viewpoints to assess these impacts and risks in the academia of China. Both viewpoints result from the bias of assessment anticipation. Land consolidation includes four main engineering aspects in China, and ecological succession from start of land consolidation to ecosystem stabilization should pass three phases. Different ecological impacts and risks of land consolidation rise from different phases of ecological successions. According to the climax theory of ecology, we developed a framework of the ecological risk assessment based on the anticipation of ecosystem stabilization (ERABAES) for land consolidation. We applied analytical hierarchical processing (AHP) method to the data resources from the land consolidation project in Southern China to allocate weightings to the indices of ecological risk (ER), and to set up an integrated index system for the ecological risk identification. This integrated index system encompasses the ecological risks with three factors (water, soil and biology) and 14 indices. The results of the project show: (1) The ER is reduced from 58.02 to 28.8 after land consolidation and the degree of ecological risk is down from Degree III to Degree IV. (2) According to the element analysis, the water ER is reduced from 21.53 to 6.16, its contribution to reduce the ecological risk is 53%; the reduced ERs of soil and biology are respectively 12.79 and 1.06, their contribution of ecological risk reduce is lower than water.

A new damage-locating method for bridges subjected to a moving load is presented, and a new ‘moving load damage-locating indicator’ (MLDI) is introduced. A vehicle is modeled as a moving load, the bridge is simplified as an Euler-Bernoulli beam, and the damage is simulated by a reduction of stiffness properties of the elements. The curvature and MLDI values at each node of the baseline model (undamaged) and the damage model are computed respectively. Then the damage or damages can be located from a sudden change of the MLDI value. The feasibility and effectiveness of the proposed method are validated by numerical simulation. The results indicate that the method is effective, being able to not only locate a single damage accurately, but also locate multiple damages in simply-supported bridges, including multiple damages in continuous bridges. The results also indicate that the MLDI can accurately locate damages under 5% measurement noise.

Water resources are one of the important factors that influence regional crop production and the food security of humans. Most traditional models of crop water demand analysis are built on the basis of a certain crop or macroscopic analysis, which neglect regional crop allocation and the difference of water demand in different crop growing periods. In this paper, a new assessing model, the satisfied degree of crop water requirement, is developed to assess the impacts of water resources on production of six main food crops in China. The six main food crops are spring wheat, winter wheat, corn, early season rice, middle-season rice and late rice. The results show that: (1) there are serious risks of water shortage in China, even in south China with its abundant precipitation; (2) the satisfied degree of crop water demand represents great temporal-spatial changes. On spatial distribution the risks are high in major bases of food production due to influences of cropping system and crop-combinations. Northwest China is a special interesting case. In seasonal fluctuation water shortage is severe in March and September. These risks seriously restrict food production in China. The results also show that the strategic measures of water resources management must be chosen carefully to deal with food security and regional sustainable development in China.

SVG is the third generation static var compensator that performs reactive power regulation by sending out capacitive or inductive current. Since numerous high power electronic components (GTO, IGBT) and PWM technology are used, the intensity and type of electromagnetic interference generated by frequent ON/OFF in a short time are far more than traditional var compensators such as capacitor bank, which threatens the safe operation of SVG body and other electrical equipments nearby. As a core component of SVG, power unit is also the most important electromagnetic interference source in SVG. This document analyzes and studies the generating mechanism of electromagnetic interference by power unit and the features of electromagnetic interference, and provides reference for further improving electromagnetic compatibility of SVG.

Compared with traditional reactive compensation equipment, STATCOM features complicated structure and numerous components. And STATCOM utilizes multiple redundancy technologies to meet long-term stable operation requirements of power system for the equipments in the substation. This paper introduces the principles of redundancy technologies currently in STATCOM control system and power system, and analyzes its practical application effect.

A quantitative description for the spatial distribution and the evolution of a crack network in mining rock stratum is one of the most difficult and fundamental problem in the subject of surface subsidence. In this paper, the physical models are employed to simulate the spatial distribution of a crack network. By using the fractal geometry, the self-similarity of spatial distribution of crack network is discovered. As a result, the conception of fractal crack network is proposed. Furthermore, the evolution of a crack network with the increasing of mining width is investigated. It is shown that (1) the spatial distribution of a crack network displays the fractal behavior, so, the fractal dimension can be used to describe quantitatively the evolution of the crack network, (2) the fractal dimension of the crack network increases with increasing of mining width, (3) the surface subsidence increases with the increasing of fractal dimension of crack network.

Settling time is a crucial design issue in Phase-Locked Loop (PLL) used in modern wireless communication systems. A Digitally Controlled Oscillator (DCO)-based multi-operational modes All-Digital PLL (ADPLL), which can achieve an ultra fast settling time of 10 µs, has been intensively researched. This paper describes a novel Counter-Based Mode Switching Controller (CB-MSC) for the ADPLL to further reduce its settling time. By monitoring the variation of DCO Tuning Word (OTW), the CB-MSC can control the ADPLL to switch from one operational mode to another quickly, which significantly reduce the mode switching time. An estimated OTW for presetting the DCO is also generated by the CB-MSC to accelerate the frequency acquisition process. The proposed ADPLL was designed in VHDL and simulated in ModelSim environment. Simulation results demonstrate that a minimum settling time of 5.7 µs is achieved and the average improvement factor is 37.8%.

The purpose of this paper is to develop a framework of ecological vulnerability assessment, and to assess the ecological vulnerability by this framework in the middle and lower reaches of the Hanjiang River Basin. Based on the theory of cause - and - consequence, we proposed an indicator system of ecological vulnerability assessment at basin scale. Twelve indicators are selected to constitute the proposed framework of ecological vulnerability assessment. Based on the Landsat TM images acquired in 2000 and technical support of ERDAS & GIS software, an empirical study was carried out. The results of study show that the general characteristics of ecological vulnerability in spatial differences in the Hanjiang River Basin are as follows: the expression of ecological vulnerability is the most vulnerable in the plain regions, the middle vulnerable in hilly regions, and the weakest vulnerable in mountainous regions.

The conjugated evolvement between land use/cover change (LUCC) and landscape pattern are appeared as their relevancies in space-time scale. In this paper, the data resources are combined the conventional maps and statistics with two temporal TM images in the middle and lower reaches of the Hanjing Basin in 1995 and 2000, and the system analysis are made to the coefficient of land use intensity (the COLUI), composite index of landscape pattern (the CILP), and their changes. The platform of spatial data processing is software ERDAS and ARC/INFO, and the attribute data are calculated with software ACCESS, EXCEL and SPSS. The results of statistical and correlation analysis show the rules of conjugated evolvement between LUCC and landscape pattern, that is, there is a remarkable negative correlation between the COLUI and the CILP in this region. In 1995, the correlation coefficient between the COLUI and the CILP is -0.572 with the confidence level 0.01, it means that the probability of negative correlation is 99%. In 2000, this correlativity is increased, the correlation coefficient is -0.683 with the confidence level 0.001, meaning that the probability of negative correlation between the COLUI and the CILP is 99.9%. The spatial analysis shows that the correlativity is associated markedly with relief types in spatial distribution in the study region. The correlativity between the indexes in the plain and mountainous regions is higher than in the hilly county, meaning that the land use structure and landscape pattern are illogicality. In the hilly county, the COLUI and the CILP are high, but the correlation is illegibility, meaning that the land use structure and landscape pattern are in reason. The temporal analysis shows that the degree of correlation is trended to increase with time.

With the project planning and design of land consolidation, an index system for the ecological risks assessment is set up based on the identification of the ecological risks with 14 indexes and three factors as water, soil and biology. The index standard is studied out, and the weighting allocation of the index system is workout by AHP. The integrated index of ecological evaluation (ER) is established. The results of the trial use of the suggested index system indicate that, (1) The ER is reduced 28.94 after land consolidation, and the ecological risk is down from level III to level IV; (2) By the element analysis, the water ER is reduced from 21.53 to 6.16, its contribution to the ecological risk is 53%; The ERs of soil and biology are respectively 12.97 and 0.79, their contribution of ecological risk are lower than water.