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This paper presents a millimeter-wave (mm-wave) on-chip coupler with tunable power dividing ratios and constant phase response. Composed by two coupled lines, two capacitors and two series-connected varactors, the proposed tunable coupler offers broadband frequency responses for 5G applications. Theoretical analysis for wideband operation is provided. For demonstration, a millimeter-wave tunable coupler is implemented in a standard 0.13-$\mu \text{m}$ SiGe (Bi) CMOS technology and measured through an on-wafer probing system. From 24 to 38 GHz, the proposed tunable coupler shows a power-dividing ratio ranged from 0 to 6.5 dB, while maintaining an in-band return loss of better than 10 dB and output isolation of 20 dB, simultaneously. The phase imbalance is better than ±2.5° with a measured insertion loss of 1.3 dB across the entire tuning range. To the authors' best knowledge, this is the first time that an on-chip coupler with tunable power-dividing ratios is reported operating at mm-wave bands for, particularly, 5G applications.

Ultrasound diagnostic techniques are widely used in medical clinical diagnostics. However, the presence of speckle noise in the ultrasound imaging process reduces the image quality and creates inconvenience to the physician during clinical diagnosis. The ability to reduce the influence of speckle noise has important significance therefore in medical ultrasound image diagnosis. This paper offers a solution. It proposes a novel despeckling method based on nonsubsampled shearlet transformation and a guided filter. First, a nonsubsampled Laplacian pyramid filter is used to decompose the noisy image thus decomposing the image into high-frequency and low-frequency subbands. Under the direction of the non-sampling filter bank, a high-frequency subband multi-directional decomposition is obtained. Next, based on the threshold function and the correlation of the shearlet coefficients in the transformation domain, an improved threshold shrinkage algorithm is proposed to perform the threshold shrinkage processing on the shearlet coefficients of the high-frequency subbands. Finally, the low-frequency subbands in the transformation domain are processed by the guided filter, and a denoised ultrasonic image is obtained by the inverse transformation of the shearlet. So as to verify the effectiveness of the proposed method, experiments were conducted, and the results were compared to those of other existing denoising filters. These showed the proposed method performs more effectively at denoising and delivers clearer image detail.

Load-variation insensitivity, for impedance matching between power amplifiers (PAs) and transmitting antennas, contributes to challenging the design of millimeter-wave wireless systems. In this paper, a $W$ -band two-way balanced PA based on a compact quadrature coupler with a broadside coupled strip-line (BCSL) as the core is presented to enhance the load-variation insensitivity and stability. The proposed coupler is truly broadband with low amplitude and phase imbalance. The proposed $W$ -band balanced PA achieves higher power-added efficiency (PAE) and unsaturated output power ${P} _{\mathrm{ sat}}$ over wide frequency bandwidth. The $W$ -band balanced PA is implemented in a 0.13- $\mu \text{m}$ SiGe BiCMOS process and achieves a measured ${P} _{\mathrm{ sat}}$ of 16.3 dBm and a peak PAE of 14.1% at 100 GHz (with 1.6-V power supply). The measured ${P} _{\mathrm{ sat}}$ with 1-dB bandwidth is from 91 to 102 GHz. The measured results present the feasibility of the compact quadrature coupler. The total chip surface area (with pads) is 0.64 mm2, where the size of the proposed quadrature coupler area is only 0.04 mm2.

This letter proposes a compact and broadband quadrature coupler with a center frequency of 55 GHz, which consists of a 90° broadside coupled-line to support the differential signal propagation and two T-type L-C networks to support the common signal propagation. To analyze the proposed coupler, an equivalent circuit model is provided for estimation of the distributed and lumped component values. The measured results of the proposed on-chip quadrature coupler show that the return loss and isolation are greater than 20 dB with a bandwidth of 105%, while the insertion loss is about −0.85 dB. The magnitude imbalances are less than 1 dB within the bandwidth of 56% and the phase differences are with ±1° errors within the bandwidth of 96.9%. The chip size, excluding the test pads, is only $0.31\times0.22$ mm2.

This chapter presents developments as part of the International Union of Physiological Sciences (IUPS) Physiome Project. Models are multiscale, multispatial and multiphysics, hence, suitable numerical tools and platforms have been developed to address these challenges for the musculoskeletal system. Firstly, we present modelling ontologies including several markup languages used to facilitate storage, sharing and exchange of numerical models. Secondly, custom software tools, CMISS and CMGUI, are then presented in the development of anatomically based geometrical models. Customisation methods are also presented to morph generic models into subject-specific representations. Thirdly, population based modelling and statistical shape analysis methods are presented as efficient techniques that harness the power of big data and imaging databases. These allow prediction of human anatomy from minimal geometric information. Fourthly, a specific example of our framework is presented in the context of a validated orthopaedic clinical tool used for assessing osteolytic defects around implants. Finally, EMG-informed muscle modelling is presented combined with medical imaging to better understand musculoskeletal injury. The problem of NaF PET CT is used to highlight the problem of patellofemoral pain.

As the COVID-19 virus spreads around the world, testing and screening of patients have become a headache for governments. With the accumulation of clinical diagnostic data, the imaging big data features of COVID-19 are gradually clear, and CT imaging diagnosis results become more important. To obtain clear lesion information from the CT images of patients' lungs is helpful for doctors to adopt effective medical methods, and at the same time, is helpful to screen the patients with real infection. Deep learning image segmentation is widely used in the field of medical image segmentation. However, there are some challenges in using deep learning to segment the lung lesions of COVID-19 patients. Since image segmentation requires the labeling of lesion information on a pixel by pixel basis, most professional radiologists need to screen and diagnose patients on the front line, and they do not have enough energy to label a large amount of image data. In this paper, an improved Dense GAN to expand data set is developed, and a multi-layer attention mechanism method, combined with U-Net's COVID-19 pulmonary CT image segmentation, is proposed. The experimental results showed that the segmentation method proposed in this paper improved the segmentation accuracy of COVID-19 pulmonary medical CT image by comparing with other image segmentation methods.

In the past decades, Computed Tomography (CT) images have been widely used and played a critically role in medical diagnosis. In low-dose CT images, reducing the radiation dose can reduce damage to patients, but at the same time, the projected image is contaminated with noise, resulting in a lot of noise in the reconstructed medical CT image, which can affect the clinical diagnosis. Based on the network structure of GoogleNet and Inception series, and combined with deep residual learning and convolutional neural networks, a novel denoising method with multi-feature extraction is proposed in this paper for medical CT images. The extraction of shallow multi-features in medical CT images is achieved by combining convolution filters of different sizes. This is useful for obtaining more detailed feature information in the image. Through the fusion of image features, the noise learning in medical CT images is realized. The developed neural network is more targeted to the removal of noise in the medical CT image. Experimental results show the denoised medical CT images can better retain edge and texture area details with the proposed method. Compared with the existing methods, the method proposed in this paper improves the denoising effect of medical CT images.

In this letter, an on-chip miniaturized bandpass filter (BPF) is presented, which is based on a grounded center-tapped ring resonator (CTRR) with shunt capacitive loading. To analyze the principle of this design, a simple but effective equivalent circuit model is provided. Using this model, it is easy to show that the CTRR-based approach has a potential to generate two transmission poles within the passband. Compared with the conventional single-pole-based approach, this dual-pole design not only possesses a flexibility of controlling the passband width, but also has better flatness of insertion loss in the passband. In addition, this approach is able to significantly improve the stopband performance. To further demonstrate the feasibility of this approach in practice, the structure is implemented and fabricated in a commercial 0.13- $\mu \text{m}$ (Bi)-CMOS SiGe technology. The measured results show that the BPF has a center frequency at 33 GHz with a bandwidth of 42.4%. The minimum insertion loss is 2.6 dB, while the stopband rejection is maintained to be better than 20 dB beyond 58 GHz. The chip, excluding the pads, is very compact at only 0.03 mm2 ( $0.11\times0.28$ mm $^{{2}}{)}$ .

This paper presents a multiple-input and multiple-output antenna using a wideband decoupling structure for enhancing isolation. The decoupling structure is formed by a split ring, which consists of an inductive line and a capacitive gap to realize magnetic and electric coupling, respectively. By introducing the electric coupling in addition to the magnetic coupling, more degrees of freedom are obtained and the original coupling between antennas can be canceled out within a wide frequency band. Meanwhile, the performance of each antenna element is maintained, such as impedance bandwidth and radiation characteristics. Theoretical analysis and experimental verification are carried out. When the decoupling structure is placed between these two monopole antennas with edge-to-edge space of only 5 mm ( $0.04\lambda _{0}$ at 2.5 GHz), more than 20 dB isolation is realized over the bandwidth of 2.3–2.9 GHz (24%) with $S_{11}$ and $S_{22}$ less than −10 dB. Moreover, the isolation levels reach more than 30 dB over the frequency band of 2.3–2.8 GHz. Compared with the previous related works using decoupling networks and neutralization line techniques, the proposed decoupling structure can provide higher isolation of over 30 dB in a wider bandwidth.

Smart cooking based on Amazon Echo uses the internet of things and cloud computing to assist in cooking food. People may speak to Amazon Echo during the cooking in order to get the information and situation of the cooking. Amazon Echo recognizes what people say, then transfers the information to the cloud services, and speaks to people the results that cloud services make by querying the embedded cooking knowledge and achieving the information of intelligent kitchen devices online. An intelligent food thermometer and its mobile application are well-designed and implemented to monitor the temperature of cooking food., 9 pages, 3 figures, 2 tables

Speckle noise is a granular artifact in medical ultrasound images. It causes serious problems and hinders the development of automatic diagnosis technology. In this paper, a novel and integrated approach is proposed to address the de-noising problem by using wavelet transformation and trilateral filter. Firstly, a dynamic additive model is developed to account for the medical ultrasound signal with speckle noise. Secondly, in accordance with the statistical property of the additive model, an adaptive wavelet shrinkage algorithm is applied to the noisy medical signal. Particularly, the algorithm is significant to the high-frequency component of the speckle noise in the wavelet domain. Thirdly, but most importantly, the low-frequency component of the speckle noise is suppressed by a trilateral filter. It simultaneously reduces the speckle and impulse noise in real set data. Finally, a lot of experiments are conducted on both synthetic images and real clinical ultrasound images for authenticity. Compared with other existing methods, experimental results show that the proposed algorithm demonstrates an excellent de-noising performance, offers great flexibility and substantially sharpens the desirable edge.

Speckle noise is an inherent yet ineffectual residual artifact in medical ultrasound images, which significantly degrades quality and restricts accuracy in automatic diagnostic techniques. Speckle reduction is therefore an important step prior to the analysis and processing of the ultrasound images. A new de-noising method based on an improved wavelet filter and guided filter is proposed in this paper. According to the characteristics of medical ultrasound images in the wavelet domain, an improved threshold function based on the universal wavelet threshold function is developed. The wavelet coefficients of speckle noise and noise-free signal are modeled as Rayleigh distribution and generalized Gaussian distribution respectively. The Bayesian maximum a posteriori estimation is applied to obtain a new wavelet shrinkage algorithm. The coefficients of the low frequency sub-band in the wavelet domain are filtered by guided filter. The filtered image is then obtained by using the inverse wavelet transformation. Experiments with the comparison of the other seven de-speckling filters are conducted. The results show that the proposed method not only has a strong de-speckling ability, but also keeps the image details, such as the edge of a lesion.

A study of lumped transformer-based directional couplers is proposed by converting a conventional two-port transformer into a four-port directional coupler. The directional coupler of this kind is a backward coupler that consists of a ferrite-core transformer and four or five associated lumped reactive elements. Four different topologies of the coupler are proposed with four different reactive element arrangements, namely, ring topology, cross topology, H-shaped topology, and twisted topology. Analysis and design equations are presented. Four different circuits with different frequency responses are derived. Four 13.56-MHz couplers with these four different topologies are designed, fabricated, and measured. Wideband, compact, and backward wave coupling features are theoretically and experimentally confirmed.

Various mobile medical APPs appear designed for mobile smart phones in China recent years, providing more approaches between patients and doctors. It offers more convenient and prompt medical information and service exchange. Though there still exist some unfavorable factors, mobile medical application improves patient medical experience, the relationship between doctors and patients, the doctor's self-price value and contain the huge commercial value. In the future, as the improvement of the laws and regulations, the increasing of the market competition and advancement of technology, it will change the medical pattern completely, especially for out-patients.

Speckle noise is an undesirable part of the ultrasound imaging process, since it can degrade the quality of ultrasound images and restrict the development of automatic diagnostic techniques for ultrasound images. Aiming at the problem of speckle noise, an improved de-speckling method for medical ultrasound images is proposed, which is based on the wavelet transformation and fast bilateral filter. According to the statistical properties of medical ultrasound image in the wavelet domain, an improved wavelet threshold function based on the universal wavelet threshold function is considered. The wavelet coefficients of noise-free signal and speckle noise are modeled as generalized Laplace distribution and Gaussian distribution, respectively. The Bayesian maximum a posteriori estimation is applied to obtain a new wavelet shrinkage algorithm. High-pass component speckle noise in the wavelet domain of ultrasound images is suppressed by the new shrinkage algorithm. Additionally, the coefficients of the low frequency signal in the wavelet domain are filtered by the fast bilateral filter, since the low-pass component of ultrasound images also contains some speckle noise. Compared with other de-speckling methods, experiments show that the proposed method has improved de-speckling performance for medical ultrasound images. It not only has better reduction performance than other methods but also can preserve image details such as the edge of lesions.

© 2017 IEEE. A 320 GHz on-chip 2 × 2 antenna array employing a compact feeding network is presented in this paper. The feeding network is designed based on the conducted-back coplanar waveguide (CBCPW) transmission line with a compact size, which has the full shielding performance providing good isolation from circuits around or below the CBCPW transmission lines. The proposed on-chip feeding network and antenna array are fabricated using standard 0.13-μm SiGe process. The antenna array is measured using a specially designed backside radiation measurement system. The simulated and measured results show that the backside radiation on-chip antenna array has a measured peak gain of 7.9 dBi at 320 GHz.

A simple control strategy with acceptable control performance can be a good choice for the mass production of ultrasonic motor control system. In this paper, through the theoretic and experimental analyses of typical control process, a simpler intelligent PID speed control strategy of TWUM is proposed, involving only two expert rules to adjust the PID control parameters based on the current status. Compared with the traditional PID controller, this design requires less calculation and more cheap chips which can be easily involved in online performance. Experiments with different load torques and voltage amplitudes show that the proposed controller can deal with the nonlinearity and load disturbance to maintain good control performance of TWUM.

It is well known that the quality of ultrasound image is significantly degraded by the speckle noise, which has restricted the development of automatic diagnostic techniques for ultrasound images, especially for the breast ultrasound images. This necessitates the need to choose an optimal speckle filtering algorithm for the specific clinical application with different required criteria. In this paper, the study focuses on the comparison of despeckle filters for the breast ultrasound images. Firstly, the models of speckle noise for medical ultrasound images are discussed. After that, eleven despeckle filters which are classified into five categories (local adaptive filter, anisotropic diffusion filter, multi-scale filter, nonlocal means filter, and hybrid filter) are described. Then, the comparative experiments of eleven despeckle filters for the two types of simulated images and clinical ultrasound breast images are presented. Finally, to objectively and systematically compare the performance of eleven despeckle filters, several comparison methods are used, such as the full-reference image quality metrics, the nonreference/blind image quality metrics, observing the removed noise images, as well as the visual evaluation of experts.

Ultrasonic motor (USM) has heavy nonlinearity, and its nonlinearity is easily changed along with the change of driving condition. Therefore, it is hard to acquire an accurate model of USM. At present, in the design of USM’s control strategy, an identification method is usually used to establish the model of USM. But the established models are always linear. Because the nonlinearity of USM system is obvious and proper nonlinear model is the foundation of excellent servo control. So in this paper, a kind of modelling method to obtain the nonlinear Hammerstein model of USM’s drive system is proposed. The structure of Hammerstein model consists of a nonlinear static element and a linear dynamic element, which can describe the nonlinearity of USM in a relatively simple form. The modelling method is on the basis of the complexity of USM itself. The parameters of the tested data are identified by using the particle swarm optimization (PSO) method which has good searching ability under complex cases. The proposed model can accurately represent USM model. That is, this PSO method makes it easier and more accurate to produce the model. Simulation results show that the data obtained from the model are close to the actual data; it indicates that the modelling method is reasonable and the established model is valid.

A multilayer technology is applied to design a dual-band branch-line coupler for the dual-band balanced amplifier. The proposed coupler is designed based on a three-layer printed circuit board. The dual-band operation is achieved by four additional shunt stubs at the middle layer, while the upper layer is the core and active circuits layer and the bottom is ground layer. The proposed coupler with equal power division is designed at two frequencies of 1.1 and 1.9 GHz. Besides, a balanced amplifier is also designed which achieves gain of 11.6 and 10.1 dB at 1.1 and 1.9 GHz, respectively. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1680–1683, 2014

A novel small-size harmonics-suppression six-port circuit based on a compact coupled-line power divider and three compact couplers with harmonic suppression is proposed and fabricated. This proposed circuit area is reduced 65% compared to the conventional one. Within the operating frequency band (f0=840 MHz), the measured return loss (|S11| to |S66|) are larger than 20 dB, the insertion loss (|S32| to |S62|) are between 6 dB and 7.5 dB, and the phase imbalances are less than 6 degree. The measured harmonics suppression of 2f0 and 3f0 are larger than 30 dB and 6O dB, respectively.

Speckle noise causes a sequence of serious problems in medical ultrasound imaging system and limits the development of automatic diagnosis technology. In the paper, a novel approach, based on wavelet transformation and trilateral filter, was proposed. The clinical images are optimized by the integrated filter. Firstly, a dynamically varying additive model is developed to account for medical ultrasound signal with speckle noise. Secondly, an adaptive wavelet shrinkage algorithm, in accordance with the statistical property of the additive model, is developed to apply to the noisy medical signal, especially with the component of high frequency in wavelet domain. Thirdly and most importantly, the low frequency component of speckle noise is suppressed by a trilateral filter that simultaneously reduces the speckle and extreme impulse noise in real set data. Finally, plenty of experiments are taken on synthetic images. And what's more, for real clinical ultrasound images, a lot of experimental studies of the proposed method are conducted. Compared with other existing method, experimental results show that the proposed approach demonstrates an admirably de-noising performance and offers great flexibility while substantially sharpening the desirable edge.

This letter proposes a compact and low-loss on-chip bandpass filter (BPF) design in (Bi)-CMOS technology. The proposed BPF consists of a self-coupled folded-line resonator and a pair of metal–insulator–metal capacitors. The proposed resonator has a property of flexible self-resonant frequency to form a transmission zero, which is analyzed in detail by a simplified LC equivalent circuit. Moreover, the parametric studies of the feeding capacitance for the proposed BPF design have been performed to demonstrate the tenability of the resonant frequency. For verification, the proposed BPF is fabricated in a standard 0.13- $\mu \text{m}$ (Bi)-CMOS technology. The measured results show that the proposed BPF has a notch with 25.4-dB suppression at 65 GHz and an insertion loss of 1.66 dB in the passband. The chip size of the device, excluding the test pads, is only 0.009 mm2 ( $0.11\times 0.086$ mm2).

Electricity production site operation and maintenance work and need to collect operation data, records information about a job, the widespread use of manual recording mode, even if the use of handheld terminal and the function is single. Based on electricity production site information collection method, and hand-held terminal application discussion, formed out of the production and operation and maintenance management needs, the networking technology and mobile Internet technology, combining with the electricity production business, into the diversification of information entry, scanning, photographs, RFID, GPS, wireless temperature measurement technology, making mobile terminal with electricity production professional, suitable for use in power production and field work, complete record of the site and the equipment, security field operation accuracy and safety. Solve the electric power production site portable mobile application, and enhance the power production terminal support.

A lumped quadrature coupler based on a ferromagnetic core is proposed for high-frequency (HF) application. The four terminals of the transformer are connected to the four ports, whereas two inductors and two capacitors are connected between two adjacent ports. The bandwidth is only limited by magnitude imbalance. A 13.56 MHz prototype is designed and tested. A 69% bandwidth is achieved with ±3 dB magnitude imbalance. Within the frequency band, the measured return loss is greater than 31.57 dB, port-to-port isolation is greater than 33.21 dB and the phase imbalance is

Wireless sensor network nodes deployment optimization problem is studied and wireless sensor nodes deployment determines its capability and lifetime. A heterogeneous wireless sensor network nodes deployment algorithm based on the perceived probability model aiming at the heterogeneous wireless sensor network nodes which are random deployed is designed in this article. The perceived probability model is used to calculate the perceived probability in the area around the heterogeneous wireless sensor nodes and transform virtual force algorithm. The algorithm moves the heterogeneous wireless sensor nodes to the low perceived probability area and achieves the maximum coverage of the monitoring area. The simulation result shows this deployment algorithm achieves the goal of the nodes reasonable distribution with improving the network coverage effect and reducing the nodes movement distance thus extends the lifetime of heterogeneous wireless sensor network.

For the existence of interference in network control system, by considering both error and error difference, a fuzzy self-adjusting PID controller based network control system is presented in this paper. In order to correspond with the practical requirements, according to the system error and error difference, the algorithm uses the principle of fuzzy to adjust PID parameters. Finally, True Time Toolbox is used to model the NCS which contains a fuzzy PID controller. we compared it with conventional PID controller. Simulation results show that, in comparison to the conventional PID controller, the proposed fuzzy PID controller provides better robustness and anti-jamming capability in the same bandwidth occupied network.

The paper presents two ways to solve the problem that S-Function could not call control algorithm function written in the m language to realize xPC target Simulation, then m function could be called in hardware-in-the-loop (HIL) simulation. The use of the proposed HIL method will accelerate the pace of the conversion of algorithm from theoretical research to practical application and shorten the product development cycle obviously. Two examples, achieving xPC target Simulation by using PID controller and Explicit Model Predictive Controller (EMPC) written in m language, verify the feasibility of the methods at the end of the article.

Due to errors existing in InSAR monitoring results, the filter is adopted for post processing to improve the monitoring results precision. Considering the existent insufficiency of weighted filter and median filter, we proposed a new idea of robust filter by using an equivalent weight, which not only think of regional statistical characteristic fully but also can resist the influence of outliers. Finally, the method is evaluated by a case study of InSAR monitoring results at one region of Xi'an in 2007. The result shows that contour has been improved obviously after treated with filter and the method of robust filter make the effect more obvious.

Different environmental management policies should be adopted in different stages, which can be recognized after studying the relationship between economic development and environmental damage. Economic development and environmental damage are associated, but the relationship is neither linear nor even monotonic. In the last few years, many studies have found an inverted-U relationship between per capita income and environmental degradation, which is known as the environmental Kuznets curve (EKC). This paper uses panel data in China on industrial waste gas emission, industrial waste water discharged and industrial waste solid discharged for the period 1996-2005 to test the relationship between per capita income and environmental pollution. The results are compared with the EKC hypothesis. Accordingly, some environmental management implications are given to coordinate the economic development and environmental protection in China.

Based upon the multi-parametric programming for the linear constrained optimization program, the explicit model predictive control systems for linear time-invariable and time-variable constrained system are established respectively. The dynamic model for the mechanical vibration of elevator is developed, and schemes for vibration control of elevator and the placement of the actuator are discussed. With the established explicit model predictive control system, the active vibration control of the mechanical system of elevator is studied. Simulations are made for different working conditions of the elevator, and results show that the proposed method in this paper is effective for active vibration control of mechanical system of elevator.

With the increasing concern about the environment and human health, questions are already being asked about what role the government should play in sustainable development - to what extent environmental-friendly technologies help in the process of achieving agricultural sustainable development? Can governments speed the diffusion of technology by offering complementary services? There exist a number of alternative methods that are not so harmful for the environment and human health, for example, integrated pest management (IPM). However, there are many obstacles for the diffusion of sustainable technologies so that the adoption of sustainable agricultural technologies lags far behind technology innovation. After reviewing the commonly used models in agricultural technology adoption, the following model is used in this paper: adopti = + f(Ri, Hi, Ti, Si, Oi) + ei in which, the dependent variable indicates whether the farmer I adopt the technology, while the independent variables represents the ith farmers' resource characteristics, household characteristics, technology characteristics, institution characteristics and others. After estimation of the adoption model and test of the hypothesis, some conclusions are made and some policy implications are proposed. The main conclusions are: (1) farmers use different strategies when facing environment and human health. (2) There are various factors that affect farmers' adoption of IPM, the adoption process is very complicated. (3) It is important to recognize the factors that affect farmers' awareness and mastery of IPM technologies. (4) Career of technology decision-maker significantly affects adoption of IPM technology. (5) Endowment of farmers especially production scale is significantly affecting the adoption of IPM. In addition, farmers' orientation to agriculture is another important factor. Accordingly, at least the following policy implications could be proposed: (1) farmers have willingness-to-pay for the environment and human health (especially the latter), so economic instruments (such as taxes) could be taken to encourage the adoption of sustainable agricultural technologies. (2) The government should recognize the characteristics of the early-adopters of sustainable agricultural technologies. (3) Markets should be created to increase the demand for organic products. (4) Farmers should be encouraged to do part-time jobs so that household land scale may be increased, and the increased scale will encourage the adoption of sustainable agricultural technologies.

Designing energy-efficient routing protocols to effectively increase the networks' lifetime and provide the robust network service is one of the important problems in the research of wireless sensor networks. Using the hyper-graph theory, the paper represents large-scale wireless sensor networks into a hyper-graph model, which can effectively decrease the control messages in routing process. Based on this mathematic model, the paper presents the minimum spanning hyper-tree routing algorithm in synchronous wireless sensor networks (MSHT-SN), which builds a minimum energy consumption tree for data collection from multi-nodes to Sink node. The validity of the algorithm is proved by the theatrical analysis. Finally, the simulation is proposed to prove the MSHT-SN algorithm is right and effective. It can increase the transmitting success rate and effectively save the scarce energy.