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Using stochastic frontier analysis, the paper measures the technical efficiency of cement industry of Pakistan. For this purpose, technical efficiency is calculated for 16 cement industries using panel data for the period 2000–2016. Two models are estimated to measure the technical efficiency of cement industry, i.e., the industrial model and the macro-model. In the former model, only industry related variables are used, while in the latter model macroeconomic variables are also used as input variables besides industrial variables. The results indicate that all industrial variables, i.e., capital, labor, raw material, repair and maintenance, energy inputs and advertisement have positive effect on production of cement industry measured by net sales. In macro-model, gross domestic product (GDP) growth and exchange rate have significant positive effect on production. It is found that one percent increase in economic growth will increase cement production by 0.061%. Similarly, one percent devaluation in exchange rate will bring 0.855% increase in cement production. The results show that there is 48.4% efficiency in cement industry of Pakistan, which indicates that cement industry in Pakistan is inefficient by 51.6%. It implies that there is a need to improve the efficiency of cement industry. Further, macroeconomic variables should be incorporated while examining the efficiency of cement industry in Pakistan.

We have developed and analysed logic NOR, NAND and XNOR gates based on two dimensional (2D) photonic crystals at a wavelength of 1.55 μm. The interference and self-collimation effects are used to design logic gates, which control the output by adjusting the phase difference to achieve constructive or destructive interference. The splitter is a line defect of the photonic crystal with a row of periodically arranged air rods. The radius of the defect rods depends on the function of the logic element. The use of these logic gates can reduce the size of logic devices.

Hundreds of static discharges were directed to a circuit board containing a custom test chip, and the resulting soft-failures were recorded. The large time-derivative of the ESD current is the primary cause of soft-failures in this system. Magnetic coupling between traces and bondwires produces glitches at IO pins; the magnitude of these glitches is increased by the bounce of the on-chip supply net relative to the on-board supply. Additionally, logic upsets due to substrate current collection are observed when the equipment-under-test is tethered, i.e., when it has a low impedance path to Earth-ground.

Developing production and operation in scales in the major grain producing areas is the direction of the paper. Seizing the opportunity of modern agriculture comprehensive reform in two plains (Songnen Plain and Sanjiang Plain) of Heilongjiang Province and supporting to build a new type of production and management based on the big grain production householding, which plays demonstration and leading roles, have an important strategic position in improving agricultural comprehensive production capacity and ensuring national food security. In this paper, based on the survey data about the big grain production households production operations and analyses of the obstacles in expansion of production in Heilongjiang Province, specific suggestions in supporting the development of the big grain production household were put forward, such as, increasing agricultural production socialized level; perfecting the service system of land transferring; improving financial policies and farmer-friendly policy measures and perfecting the agriculture socialized service system.

In order to improve the accuracy and efficiency of traditional short-term building load forecasting, this paper proposes a new load forecasting method that is based on similar day selection and LSTM network model. The algorithm is divided into two parts. The first part is to establish similar day sets and complete pattern matching. The purpose is to select and optimize the input variables of the prediction model for improving the prediction efficiency. For a start, the similarity index (the human comfort index) of the historical data and the forecast day is calculated, and then K-Means clustering algorithm based on particle swarm optimization is made to establish similar day sets. The next, the forecast days are taken to perform the similar day matching according to the Euclidean distance method. The second part is to establish the LSTM prediction model, train the variables that are filtrated in the first part and complete the prediction. Taking the actual data of a hotel building in Shanghai as an example, the results prove that the method is more accurate and effective than the traditional method.

A semi-custom microcontroller is subjected to IEC-61000-4-2 ESD. A scan chain and memory read-out programs enable identification of the hardware blocks that experience soft failures. Voltage monitors are used to correlate the occurrence of those failures with the magnitude of noise on power supplies.

This paper presents an accurate model to forecast voltage deviation with improved BP neural network, which concerns with the meteorological factors. The proposed method is a combination of PCA dimension reduction, AP clustering and BP neural network. In this paper, the PCA is used to reduce the dimension of the input data, and the AP clustering is employed to classify input data into clusters. Finally a forecast of voltage deviation is made by using BP neural network. The proposed method is successfully applied to real data. A comparison is made between the proposed method and the other methods. The practical application results proved that the mean absolute percentage error(MAPE) of the proposed method is 3.06%,and the probability of the relative error less than 3% is 54.17%,which are obviously better than that of the other methods.

In order to further study the coupling of three energy flows of electricity, heat and natural gas in integrated community energy system, based on the theory of energu hub, this paper has proposed the universal energy hub model for different load types in winter and summer, and established the coupling matrix and the operation mode of the model, combined with the natural gas pipeline network and distribution network steady state calculation connected to it, thus to obtain the energy allocation plan for energy hub. Taking Matlab and its Simulink as the platform, the simulation of the system was achieved, and as the calculation proves that, the proposed model and calculation method can be used to analyze the coupling degree of different energy flows in energy hub, the algorithm can reasonably reflect the characteristics of steady state in the integrated community energy system.

An active rail clamp circuit provides protection against component-level ESD; this work explores the challenges associated with designing a rail clamp to additionally provide protection when the IC is powered on. The fast transient response required to protect against ESD makes it difficult to design a stable circuit and introduces tradeoffs between supply integrity and the clamping characteristic. This work presents an analysis of how these performance metrics are affected by device sizes. Interactions between a rail clamp circuit, which may be an active or passive clamp, and the parasitic elements of the package and board are examined; it is shown that these interactions may briefly power down the supply.

In recent years, the great achievements of basic medical and healthcare services of BRICS have gained great attention and acknowledgement from the whole world. In their medical system reform, India, Brazil, Russia and South Africa have established their medical systems with their own characteristics. This provides valuable references for China in its critical stage of medical system reform. This paper explored the experience of BRICS’ reform of medical system in order to offer some references and guidance for the establishment of basic medical and health services with Chinese characteristics and conforming to Chinese practice.

Two supply noise monitor circuits are demonstrated on a 130-nm test chip. These monitors are capable of providing quantitative measurements of on-chip supply voltage perturbations resulting from system-level ESD. Circuit-level simulations reproduce all trends found in the measurement results.

– Hybrid super-capacitor and battery energy storage combine the advantages of power-type energy storage element and energy storage components, to avoid the disadvantages of a single energy storage technology, which is one of the important development direction of the energy storage technology. For energy storage applying in high-power, high-capacity and strong volatility applications, the article analyzes the composition of the total cost of the objective function in the hybrid super-capacitor and battery energy storage system entire life cycle, with regard to two decision variables - the number of each energy storage element batch and the batch of energy storage element in the objective function, proposing calculation method of energy storage component number and batch based respectively on Ragone plots and the equivalent cycle life. The example proves the effectiveness of the proposed method.

This paper contributed to the pool of studies about agricultural surplus labor in China, also acted as the root to the imminent settlement of the issues concerning agriculture, countryside and farmers. Using data from survey of agricultural surplus labor in 2012, which covered three provinces in northern, midwestern and southern parts of China, this paper analyzed the influential factors on agricultural surplus labor professionalization by adoption of a logistic regression model. It showed that agricultural surplus labor shortage could be explained by low-quality professionalization. It was a feasible and effective way to solve the issue of workforce shortage during economic downturn by improving agricultural surplus labor's professionalization.

According to the records that the too-high temperature rise of equipment leaded to accidents easily, the temperature monitoring system based on ZigBee and GPRS, RS232 technology is designed. The perception layer uses the heterogeneous network topology by adding appropriate heterogeneous nodes to ordinary ones, which are much better than the ordinary in computing power, storage capacity, etc, and this topology structure extends transmission distance. Both of them use CC2530 chips, and the heterogeneous nodes are not only responsible for collecting temperature data, but also responsible for forwarding data from ordinary nodes. The sink nodes send alarm messages to staff by GPRS, and forward data from heterogeneous nodes to a PC via RS232. The system uses Visual Studio for software design to realize the function of data processing, display and storage, in order to achieve real-time monitoring of substation equipment and early warning.

Energy is the material foundation to promote social progress and of humans survival. A large number of energy consumption has brought serious environmental problems. After Global Climate Summit in Copenhagen, The attention to the green-house gas emissions of our country from the international community grows day by day. Developing green power is vigorously an important way to reduce the emissions of greenhouse gases. However, the cost of green power is so high compared with the traditional fossil energy that green power cannot be promoted only depending on market mechanism. So the mechanism that supports green power should be established. Firstly the implementation of green power of foreign countries (mainly the United States and European Union countries) is analyzed, and its content includes implementation mechanism, the market main body and duties, policy, motivation, supervision, etc. Then the development of domestic green power is described in detail, and a comparative analysis is presented between foreign and domestic implementation of green power in various aspects. Now in our country, the provinces developing green power better are Jiangsu, Zhejiang, Shanghai, Beijing and so on. There are enough green-power resources, potential users in these regions. And with the excitation of national policy, the regions develop green power actively, laying foundation of implementation of green-power mechanism. Shanghai is now the first city of our country that implements mechanism of green power. After the analysis of the present implementation of green power, the deficiency and areas in need of improvement are presented, combined with Shanghais present green-power implementation mechanism, as well as the original national green-power implementation mechanism. And some policy suggestion is put forward for the recent national green-power development in finance, taxation, incentive etc, which analyses and improves the designation of green-power implementation mechanism, including the payments balance and the research of incentive mechanism.

The existing laser marking control systems are mainly based on PC and PCI laser drivers. PC is used for editing marking information and extracting marking data. The rapid processing capacity of PC makes the laser making machine achieve faster processing speed. However, it cannot be used in the outdoors and bad situations. In older to make the laser marking system widely adapt to various environments, an embedded laser marking controller is developed. It is based on ARM9 and LINUX. It can be easily operated and can achieve wonderful marking.

To eliminate the overshoot of lensbarrel of an aerial camera in process of position control,a tracking differentiator was used to process step signals and to design a position transient process to control accurately the lensbarrel position without overshoots.First,the theory of the tracking differentiator was described and its characteristics were expatiated.And then,by taking position step response with a 90° input as an example,the transient process was designed and compared with that of no transient process design.Experiment results show that the position overshoot of lensbarrel can be eliminated completely through the appropriate transient process design,and the regulation time is reduced also.In the case of 90° step input,the system overshoot is reduced from 24.4% to zero and the regulation time is shorten by 28.8%.Furthermore,the fast position control of the lensbarrel was realized with non-overshoot in omnirange,in which the least square method was used to fit a curve of step input and a speedability parameter in transient process.The optimum parameter of the transient process was calculated according to the step input in control process.This method has been used in the lensbarrels of aerial cameras,and it obtains a good effect and provides significant and practical values for improving the dynamic performance of systems.

This paper presents a case study to demonstrate that transient-triggered ESD protection circuits may fail the DPI automotive requirement. A novel scheme is devised to improve the DPI performance of a MOSSCR protection device while maintaining the system-level ESD performance.

In the process of mid-long term load forecasting, it is important to choose right models according to the trend of the historical data. This paper chose the continuous 11 years electricity data of a certain district in Lianyungang to make up the historical data. Five forecasting models were always used in load forecasting field to forecast the electric quantity of the twelfth year. The data, which had been chosen in this paper, had the feature-the medium-term data showed fluctuation and the overall rising tendency was unstable. In order to check the forecasting results whether meet accuracy requirement, the concept of the grey relational degree was introduced. In terms of problems that even the forecast models meet the requirements of the grey relational degree, the forecast results still have great differences. According to the feature that the growth rate of load data is non-after effect property of Markov chains, by analyzing the growth rate of load data, using Markov chain to divide the growth rate to three state intervals, and getting the Markov state-transition matrix. According to the growth rate between the tenth and the eleventh data, combining with the Markov state-transition matrix, judging the rising tendency of the growth rate between the eleventh and the twelfth data. According to the rising tendency, screening two kinds from the models which had met the accuracy requirement, the method of variance-covariance was used to assign weights. Calculating results show that more targeted models could be chosen and combined. By this method of screening, not only can be appropriate for the rising tendency unstable data, but have a high precision.

On-chip power supply integrity may be compromised during a power-on ESD event, e.g. system-level ESD. Experimental data are provided to show that the supply integrity is a function of the rail clamp gain, its speed of response to ESD, and the amount of on-chip supply decoupling capacitance. It is also demonstrated that just a few nH of package inductance can cause the on-chip supply to briefly collapse, regardless of the rail clamp response speed.

The pulse width dependency of the failure current for NPN structures in a 0.18-μm BiCMOS technology is studied using measurements and TCAD simulation. The desired “Wunsch-Bell” behavior is not observed due to formation of current filaments in this device; however, the failure current for long pulse widths can be increased by layout changes.

An active disturbance rejection controller was designed in the lensbarrel of an aerial camera to reduce the disturbance caused by an eccentric cam of the lensbarrel.An extended state observer was designed to estimate the disturbance and then to generate control signals to compensate the disturbance influence.First,the disturbance characteristic of the cam was analyzed.And then,a mathematic model of lensbarrel was established and simplified.Based on bandwidth parameterization,the extended state observer and the control law with disturbance compensation were designed and a position controller was finished.Finally,an experiment on the lensbarrel was performed to test the disturbance rejection performance of the controller.As compared with the traditional first order square lag-lead compensation method used in aerial cameras,experiment results show that the active disturbance rejection controller can reduce the disturbance error about 50% with a lower controller gain about percentile.In conclusion,the disturbance rejection performance of the system is improved and the demand for controller gain is lowered at the same time.It is feasible and practical.

Wind power has become one of the fastest growing new energy in China, which has important market prospects and research value. This paper analyses the regional distribution of wind power installed capacity and its characteristics in China by the method of cluster analysis. With the Panel Data of 13 selected provinces from 2004 to 2008, it also analyses the impact factors of China's wind-generated electricity. The results show that the regional distribution of wind power investment basically corresponds to the wind resources distribution, but the Xinjiang region has not been developed effectively: investment in wind power significantly affects the level of wind-generated electricity; wind electricity presents reverse distribution compared to the electricity consumption. Therefore, policies such as overall planning, oversea markets expanding should be applied proactively in China's wind power development.

“...there are certain limitations to drug-eluting balloons ... such as the relatively high rate of bail-out stenting in case of unsatisfactory angiographic results, significant heterogeneity among different drug-eluting balloons and limited data from clinical trials.”

Cardiac surgery is a very common operation nowadays all over the world. Median sternotomy is a routine procedure required for cardiac access during open heart surgery. The complications of this procedure after the cardiac surgery range from 0.7% to 1.5% of all cases, and bear a high mortality rate if they occur. Every individual surgeon must pay great attention on every detail during the sternal closure. This article shows the details as to conventional information and updated progress on median sternotomy closure. The update contents involve in biomechanics, number of wires twists, biomaterial and so on. According to our experience, we recommend four peristernal single/double steel wires for sternal closure as our optimal choice.

We give an analysis of the frequency distribution trends in the four lowest bands of two-dimensional square lattices formed by holographic lithography (HL) and in the lattices of the same kind but with regular dielectric columns with increasing filling ratios, and then present a comparative study on the left-handed properties in these two kinds of structures using plane wave expansion method and finite-difference time-domain (FDTD) simulations. The results show that the left-handed properties are more likely to exist in structures with large high-epsilon filling ratios or in a connected lattice.

A new ternary photopolymer system is used in fabricating photonic crystals (PhCs) with controlled defects by combination of single-photon and two-photon photopolymerization. The former process can produce PhCs in one-step recording with a low-power (tens mW) continuous-wave laser at 532 nm, while the latter can create desired defects. The preparation of the material, the optical setup and the preliminary experimental results are given. Compared with other methods, this approach is much more accessible and convenient for use of visible light and has advantages of making PhCs in a large scale quickly and economically and introducing any defects exactly, especially for three-dimensional structures.

A custom test board facilitates TLP characterization of the external pins of an integrated circuit. Models extracted from the data are used to simulate the pin-level response of the IC to an IEC 61000-4-2 discharge. ESD gun zaps are applied to the test board; simulated and measured waveforms are compared.

The IEC 61000-4-2 test bed is modeled with circuit elements extracted from S-parameter measurements. Simulated current waveforms are consistent with measurement for both battery operated and tethered equipment-under-test without customizing the model parameters for each case.

Mobile cloud computing is a powerful technology for supporting the growing demand of mobile applications. Unfortunately, existing mobile cloud service architectures are imperfect since mobile devices are not considered as the available resources. In this paper, a general framework is proposed that regarding mobile devices as resources by introducing proxy. Differs from other architectures, this framework is the cost-aware that can select appropriate task allocation strategy based on user's demands. The possible solutions of key technologies are also discussed, including reliability measure and task allocation strategy. Particularly, a suitable method is proposed that combine statistical-based with group-based method for reliability measure, and the allocation strategy with cost-aware for distributing mobile resources evenly is also designed.

Objective. Prolactin plays an important role on the disease flare of postpartum SLE patients. 76 pregnant SLE patients were enrolled in this study to evaluate the efficacy of bromocriptine (an inhibitor of prolactin secretion) on preventing the postpartum disease relapse.Methods. Patients were randomly divided into the treatment group (bromocriptine, 2.5 mg oral, twice a day for 14 days after delivery) and the control group. All the patients were followed up for 12 months. Clinical features were recorded every 4 weeks. Serum prolactin and estradiol levels were measured at the second week and the second month after delivery. The endpoint of the study was disease relapse and defined when SLEDAI score increased by ≥3 points from the antenatal baseline.Results. (1) Serum levels of prolactin and estradiol decreased significantly in bromocriptine treatment group at the second week (P<0.001) and second month (P<0.05) after delivery compared to control group. (2) The relapse rate of the treatment group was lower than the control group (χ2=4.68,P=0.0305).Conclusions. Two weeks of oral bromocriptine treatment in postpartum SLE patients may relieve the disease from hyperprolactinemia and hyperestrogenemia and may be beneficial in preventing the patients from disease relapse.

The security routing protocol for Multi-Input-Multi-Output Vehicular Ad-hoc Network (MIMO-VANET) which is used to prevent the eavesdropping in VANET was presented in this paper. When building the routing table, this protocol stores the current channel states and restricts the VANET nodes, excepted source/ destination nodes, from obtaining the unrelated routing information. During the information transmission process, the presorted channel states in network layer are transparently transmitted to the physical layer, and decomposed as total channel state. The decomposed results, which are only known by the source/destination nodes from routing information, can be utilized to equalize the channel and to demodulate the information. As a result, the other nodes cannot effectively equalize the channel, which causes little information can be eavesdropped. The theory analysis and simulation illustrate that, when the destination nodes obtain the good signal quality, the eavesdropper suffers poor bit error rate.

The bound solitons in a passively mode-locked fibre ring laser are observed and their formation mechanism is summarized in this paper. In order to obtain stable bound solitons, a strong CW laser field at the centre of the soliton spectral is necessary to suppress and synchronize the random soliton phase variations.

We have demonstrated a novel tunable linear cavity Er3+/Yb3+ co-doped fiber laser, which utilizes amplified spontaneous emission as a secondary pump source so that it can operate in L-band. The tuning wavelength range can be up to 34 nm, from 1588.6 to 1622.6 nm, and the output power excursion of the laser at different wavelengths can be less than 0.4 dB by using a two sections of high-birefringence fiber loop mirror as the wavelength filter. The high output power of 200 mW is realized by using the cladding-pump.

This paper is focused on ecological assessment of the status of bio-diversity, and a strategic plant for biodiversity conservation on a sustainable basis. It described the present situation, the causes of bio-diversity degradation, and the approaches for conserving, utilizing and developing bio-diversity in Changbaishan Biosphere Reserve.

In paper, the problem of robustify LQR for a class of uncertain linear systems is considered. An optimal controller is designed for the nominal system and an integral sliding surface is constructed. The ideal sliding motion can minimize a given quadratic performance index, and the reaching phase, which is inherent in conventional sliding mode control, is completely eliminated. Then the sliding mode control law is synthesized to guarantee the reachability of the specified sliding surface. The system dynamics is global robust to uncertainties which satisfy matching conditions. A GROSMC is realized. To verify the effectiveness of the proposed scheme, a robust optimal sliding mode controller is developed for rotor position control of an electrical servo drive system.

The object studied in this article is 50–100kW low-voltage industrial and commercial customers in Shanghai. From statistical view, based on two partial price system feasibility analysis of small sample user with maximum demand, small sample user price features is extended to general user with nonlinear curve fitting, the maximum demand of general user is obtained. Then general user two partial price is calculated and analyzed, the conclusion is that the price variation features of general user and sample user are basically the same. The new two partial price system has feasibility and scientific.

Micro-grid is a novel unit integrated by distributed generation access to distributed network, and it is also the trend of the development of the future. Suitable micro-grid control strategy design is the key for ensuring the stability of the micro-grid under different operation mode, especially when changing from the grid connected operation to the islanding operation. This paper presents a droop control model consists of the power control loop and the voltage-current close loop control algorithm required for a micro-grid system containing micro turbine, and designs the parameters of the voltage-current close loop controller to make the inverter output show inductance characteristic. According to the simulation, the designed multi-loop controller can achieve the smooth changing between the utility connected operation and the islanding operation, proving the effectiveness of the control strategy.

This paper aims to analysis the application effect of the internet courses of aerobics for the universities students through information retrieval, mathematical statistics, survey method and experimental method, and the writer designed and developed the internet courses of aerobics for the universities students.