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Ultrasound computed tomography (USCT) has been developed as a promising tool for breast cancer diagnosis and screening. One of the USCT reflection image reconstruction methods is synthetic aperture (SA), which can achieve isotropic high-resolution images. However, to reconstruct high-quality images, data acquisition strategies commonly involve full-matrix capture (FMC). FMC can lead to a time-consuming scanning process and heavy data-process demands, thus resulting in low clinical throughput. This paper proposes a framework for image restoration from sparse transmissions (TX) based on a deep convolutional neural network and demonstrates its performance with breast imaging in vivo. The expected image quality can be restored from the trained network with images reconstructed from only 8 TXs. To generate high-resolution reference images from the FMC data for training, a modified SA method was developed, which considered the sound speed difference between the coupling medium and the object. The corresponding network input images were reconstructed using sub-sampled data from 8 TXs distributed uniformly. The U-Net deep learning network was trained to remove the artifacts in reflection images reconstructed from sparse TX. The performance of the proposed framework was evaluated in terms of the structural similarity index measurement (SSIM) and the peak signal-to-noise ratio (PSNR). The results demonstrated that the trained network was capable of enhancing the image quality. The proposed framework provides an efficient approach for the reconstruction of high-quality reflection images from sparse data acquisition scheme, which can also benefit other ultrasound imaging applications by accelerating data acquisition and image reconstruction process.

Increasing attention has been attracted to the research of ultrasound computed tomography (USCT). This paper reports the design considerations and implementation details of a novel USCT research system named UltraLucid, which aims to provide a user-friendly platform for researchers to develop new algorithms and conduct clinical trials. The modular design strategy is adopted to make the system highly scalable. A prototype has been assembled in our laboratory, which is equipped with a 2048-element ring transducer, 1024 transmit (TX) channels, 1024 receive (RX) channels, two servers, and a control unit. The prototype can acquire raw data from 1024 channels simultaneously using a modular data acquisition and transfer system, consisting of sixteen excitation and data acquisition (EDAQ) boards. Each EDAQ board has 64 independent TX and RX channels and 4 Gigabit Ethernet interfaces for raw data transmission. The raw data can be transferred to two servers at a theoretical rate of 64 Gbps. Both servers are equipped with a 10.9 TB solid-state drive (SSD) array that can store raw data for offline processing. Alternatively, after processing by onboard field-programmable gate arrays (FPGAs), the raw data can be processed online using multi-core central processing units (CPUs) and graphics processing units (GPUs) in each server. Through a control software running on the host computer, the researchers can configure parameters for transmission, reception, and data acquisition. Novel transmit-receive scheme and coded imaging can be implemented. The modular hardware structure and the software-based processing strategy make the system highly scalable and flexible. The system performance is evaluated with phantoms and in vivo experiments.

In order to optimize the response characteristics of PIN photodetectors to incident light signals, according to the carrier rate equation and considering the parasitic parameters of the chip and the parasitic parameters of the package, the equivalent circuit model of the photodetector was derived. In addition, the effects of reverse bias voltage, I-zone width, photosensitive surface, chip parasitic resistance and capacitance, package parasitic resistance, capacitance and inductance on the pulse response characteristics and frequency response characteristics of photodetectors were simulated. The results show that by increasing the reverse bias voltage, reducing the photosensitive surface and parasitic parameters (chip parasitic capacitance and resistance, package parasitic capacitance and resistance), selecting the appropriate I-zone width, , using the resonance effect of the lead inductance, it can suppress the waveform response to generate waveform distortion as well as improve the frequency response bandwidth.

The ultrasound computed tomography system based on the ring probe adopts sequential single-slice scanning mode. The ring probe keeps stationary when the scan is in process; after the signals of one slice are captured, the ring probe steps along the elevation axis to scan the next slice. The scanning process needs to step and stop repeatedly, and the scanning time is relatively long. Also, the lack of signals between tomographic image slices may result in missed diagnosis. This paper proposes a new spiral synthetic aperture method for ultrasound tomographic volume imaging. The ring probe moves along the elevation axis at a certain speed, while the transmitting and receiving array elements are switched electronically. Therefore, “spiral” transmitting aperture and receiving aperture are formed, and continuous three-dimensional spatial spiral data are collected to directly reconstruct the three-dimensional volume image. Preliminary experimental result shows that this method can shorten the scanning time and improve image quality in the elevation direction.

Oxy‐fuel combustion is one of the most promising technologies for large‐scale CO2 capture and storage in power plants. This flexible technology can be used in new power plants and in existing plant retrofits, with no technological barriers to its implementation. In this paper, economic research was conducted into a 200 MW power plant using oxy‐fuel combustion. The paper has important implications for the large‐scale application of oxy‐fuel combustion. Different combustion modes (conventional combustion, and oxy‐fuel combustion including dry and wet recycling) were considered. Several factors were taken into account, including the operation parameters of equipment and the parameters of the flue gas. The dynamic investment cost, the annual cost, the non‐taxable electricity price, energy consumption, and other data were obtained. It was concluded that, with a CO2 capture efficiency of 90%, the CO2 emission reduction cost of 200 MW under an oxy‐fuel combustion system is about 413 yuan/t. This research can provide accurate cost information for specific projects, and provide economic and cost references for other oxy‐fuel combustion projects. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd.

Based on mathematic simulations, the impact of spectral filtering on pulse breaking up and noise-like pulse generation in all-normal-dispersion fiber lasers are investigated. Three types of spectrum filters are employed in the simulations, which have a Gaussian-shaped profile, super-Gaussian-shaped profile, and sinusoidal-shaped profile, respectively. With the Gaussian-shaped filter, the pulse breaking-up process is discussed. The super-Gaussian-shaped filter and the sinusoidal-shaped filter have two different formation mechanisms for noise-like pulses and are revealed. In addition, with the sinusoidal-shaped filter, dissipative solitons of different central wavelengths are achieved.

The mechanism of occurrence of sigmoid sinus dehiscence/diverticulum (SSDD) in pulsatile tinnitus (PT) patients remains under debate. Its association with idiopathic intracranial hypertension (IIH) lacks evidence, which is important for therapeutic planning and improving the clinical outcome. This study aimed to evaluate the association between SSDD and IIH by comparing the prevalence of several established imaging features of IIH between PT patients with SSDD and healthy volunteers. Thirty-three unilateral PT patients with SSDD identified on CT images and 33 age- and sex-matched healthy volunteers underwent T1-weighted volumetric magnetic resonance imaging (MRI). The optic nerve, pituitary gland, transverse sinus, and ventricles were assessed. The prevalence of established IIH imaging features was compared between the two groups. Furthermore, the PT patients were divided into two subgroups: PT patients with dehiscence only and PT patients with diverticulum. The same statistical analysis was performed on each pathophysiologic entity respectively. The PT patients with SSDD showed a significantly higher prevalence of empty sella (P

UAV aerial has been used more and more widely in transmission line inspection. However, the automatic recognition of the visible image still can't meet the actual requirements, fault diagnosis is still largely done by hand, and infrared images contain fewer environmental factors in comparison and can basically reflect a variety of insulator faults, so it is more practical than visible image in the identification and fault diagnosis of insulator. In this paper, a method of insulator identification based on infrared image is proposed; in turn extracting surf feature points of image, K nearest neighbor matching, adaptive spatial clustering and segmentation correction are performed, then the axis and axis temperature of the insulator is extracted. The method gives full play to the advantages of infrared image and can accurately identify the insulator; it lays the foundation for insulator fault diagnosis based on infrared image.

Recently, people pay more and more attention to the healthy lifestyles. And there is an increasing demand for the green agricultural products in real life. With the rapid development of the computer network technology and the electronic commerce, the emergence of e-business provides a new idea to promote the service of agricultural products. A huge supply chain network is established by the new idea and the technology. More and more agricultural products firms establish the electronic sale channel and get great profits. Firstly, we analyze the status of the agricultural products logistics distribution in both traditional sale channel and electronic sale channel in this paper. Then, we summarize the problems appeared in e- commerce channel. To solve these problems, we build an optimization model of the agricultural products distribution in e- commerce channel.

Cloud computing, Internet of things, social networks and other new services make human society's data type and size increase at unprecedented rates. In order to analyze and make use of the huge data resources, the effective data analysis technique needed to be used. Thus, an optimized fuzzy clustering method GAPSO-FCM is proposed in this paper. The GA and PSO algorithm is adopted in order to overcome FCM be sensitive to initial value and noise problems and easy to fall into local minimum value. The combination of PSO and GA algorithm can partly solve the problem that is easy to appear premature phenomenon to PSO algorithm. It improves the global search ability by combining GAPSO algorithm and FCM algorithm. At last, the algorithm is used to analyze the comprehensive economic strength of cities in the Yangtze River Delta.

As the industrial environment becomes more competitive, supply chain management has become essential. The objective of this research is to develop a multi-echelon inventory model for a deteriorating item and to derive an optimal joint total cost. Inventory models for the manufacturer and the retailer were developed when deteriorating rates were constant, and demand rate of customer decreased linearly with time and depended on retailers’ current inventory level. The objective was to develop an optimal ordering strategy for retailers to minimize the average total cost of this inventory system. This paper establishes an inventory model of manufacturers and retailers, and gives the optimal production time algorithm. Then, we will carry out simulation test for example. We calculate the system of minimum average total cost that respectively from producers, retailers and integration. Thus, it confirms that the average total cost which from the supply chain integration is lower than from the manufacturer or retailer alone.

with the development and popularization of online games, virtual network world becomes an inseparable part of people's life, and the network virtual property also forms immediately. Our country's online game industry develops rapidly, and it involves a great amount of virtual property. Our country's tax law today has not established a sound tax collection system aiming at virtual property; academic circle does not pay enough attention to it, either; judicial practice calls for filling the gap in tax law field as soon as possible and taking virtual property into tax collection scope. This article mainly explores how to make tax collection on online games’ virtual property more rational, legitimate and feasible; how to determine tax collection on virtual property: subject of tax payment, tax category, choosing of tax item, calculation on tax payable, and so on whereby this article proposes advice on perfecting processing problem of tax collection on virtual property.

With the development of economy and society, the management mode and business of taxpayers have been updated; the complexity of tax administration significantly increased; the asymmetry of levying for both information have become increasingly prominent; therefore, the traditional way of managing households according to their apanage by tax administrator has been difficult to adapt to new needs of tax source management. We should base on information technology to build a new tax management mechanism (system) under the government leadership where national tax system and local system cooperate, and relevant department must give info-technical support, to form the comprehensive taxation atmosphere with definite power and duty, standard management, effective collaboration and powerful supervisory control in order to improve the work of information management tax.

Confocal laser scanning microscopy(CLSM) is an invaluable tool for a wide range of investigations in the biological and medical sciences.A type construction of laser con-focal scanning and fluorescent detection system was provided.A polygon mirror and a galvanometer scanner were used to implement x-y scan.The relay optical system was designed based on commercial lens with optimized consideration to achieve small scan spot size,large Field-of-View and high efficiency.Fluorescence was detected by a photomultiplier tube with excellent signal-to-noise ratio.The scan system control and image acquisition were designed with an optimized scan velocity and sample clock.All these measures could reduce the blurring effect in the whole imaging process and improve the resolution.The analysis results show that the design of the CLSM is reasonable and all components achieve an optimized consideration for in-vivo scanning imaging;this type of CLSM are easily accessible and can be upgraded according to optical requirements;the performance is comparable to available commercial products,but is superior in many aspects of cost,flexibility and versatility.

Background. Although air cells within temporal bone may play an important role in the transmission of pulsatile tinnitus (PT) noise, it has not been studied systematically.Purpose. To evaluate the difference in temporal bone pneumatization between PT patients with sigmoid sinus diverticulum and/or dehiscence (SSDD) and healthy people.Material and Methods. A total of 199 unilateral persistent PT patients with SSDD and 302 control subjects underwent dual-phase contrast-enhanced CT (DP-CECT), to assess the grade of temporal bone pneumatization in each ear.Results. In the bilateral temporal bone of 302 controls, 16 ears were grade I, 53 were grade II, 141 were grade III, and 394 were grade IV. Among the affected ears of 199 PT cases, 1 ear was grade I, 18 were grade II, 53 were grade III, and 127 were grade IV. There was no significant difference in the pneumatization grade between the affected PT ear and either ear in the healthy subjects(p>0.05). Conclusion. Although air cells within the temporal bone are an important factor in the occurrence of PT, its severity does not differ significantly from the pneumatization of healthy people.

Blood management is critical in total knee arthroplasty (TKA). In bilateral, single stage TKA, blood loss seems more prominent. We believe it is important to control all potential bleeding within the wound tissue. The purpose of the study was to evaluate a series of topical procedures used to reduce blood loss and transfusion in single-stage bilateral cemented total knee arthroplasty: antifibrinolysis with tranexamic acid, vasoconstriction with epinephrine, sealing of the bone section intraoperatively, and closure of the drainage tube within the first 4 h postoperatively. Patients with osteoarthritis of the knees were randomly divided into two groups. In group A, 5 ml (25 mg/ml) tranexamic acid (TXA) and 5 ml analgesic containing epinephrine (3 μg/ml) solution were injected at several points into the posterior capsule before installation of the prosthesis. The femoral medullar canal was closed with autograft bone and then sealed compressively with cement. Before the tourniquet was released, 10 ml TXA solution and 10 ml analgesic containing epinephrine were injected at several points into the periosteum, synovium, joint capsule, tendons, and deep fascia tissue (injection of analgesic containing epinephrine into subcutaneous fat and dermis was avoided). The residual nail holes in the bone and the uncovered bone section were covered with bone wax. The tourniquet was then removed, and active bleeding points were stanched. TXA solution (20 ml) was injected into the articular cavity after wound closure. The drainage tube was clamped for 4 h, then opened. In group B, injection of analgesic containing epinephrine into soft tissue, control of active bleeding, and clamping of the drainage tube for 4-h, only, were performed. Ninety patients were enrolled in the study. Compared with those in group B, intraoperative blood loss, drainage volume, total postoperative blood loss, and number of patients requiring allogenic blood transfusion were significantly reduced in group A. There was no significant difference between the incidence of complications in the groups. Our topical procedures enable effective and safe reduction of blood loss and the number of patients requiring transfusion in single-stage bilateral osteoarthritic TKA.

With China's higher education from “elite” to “popular” and the change of education investment system, China's colleges and universities are faced with fierce competition. China's higher education must carry on the transformation from “quantity” to“quality”. Practice shows that, the level of management's quality of higher education directly determines the historical process and the pace of construction of powerful nation in higher education. This paper examines the management's quality of higher education in China from the establishment of higher education power perspective, analyzes the existing problems, and puts forward the strategies.

Nitrogen fertilizer has played a major role in the global food production over the past 60 years. And about 50 percent of total N comes from fertilizer supply. However, fertilizer N has a low efficiency of use in agriculture (10-50 percent for crops grown in the fields). One of the main causes of low efficiency is the large of N by leaching, runoff, ammonia volatilization or denitrification with resulting in pollution of groundwater and atmosphere. With the limitation on arable land area and the demand for more and more food production, the only way is to increase the efficiency of use of fertilizer N. Thus, it is important to know the forms and pathways of N loss and the factors controlling them so that procedures can be developed to minimize the loss and increase N use efficiency (NUE). A conceptual scheme indicates the nitrogen cycle in crop production systems. Annual N input was about 170 Tg, and about half of added N is removed from the field as harvested crop (85 Tg). The remainder of the N, defined as surplus N, either is lost to the environment or accumulates in the soil (Fig.1). Food demand of the public is the major promotion for rapid development on intensive agriculture, which is becoming a dynamic industry in China. However, with an excess amount of nitrogen from animal manures and commercial fertilizers, many pollutant incidents have been found and reported on nitrate contamination in intensive agriculture especially in greenhouse vegetable production systems (Zhang, 1996; Ju, 2007; Li, 2002; Song, 2009). Environmental and economic concerns have prompted agriculture researchers and producers to seek for more and more efficient strategies for nutrient managements. The present public concerns on nitrate management are focusing on N, which exceeds crop demand and might migrate from agro-ecosystem to groundwater and surface water (Daniel, 1994). Economic considerations in nitrate managements mainly focus on efforts to improve N utilization and reduce costs of N inputs. Based on its necessity for mobility in the soil and risk to environment systems, popular N management thus aims to balance N inputs with

Educational development is inseparable from excellent teachers and cultivating outstanding vocational education teachers is the precondition for vocational education development. At present, the vocational education teachers’ status, whether seen from quality or from quantity, can not adapt to requirements of modern vocational education development, so intensifying and speeding up the efforts for cultivating vocational education teachers so as to guarantee the quantity and quality of vocational education teachers is the first question to be solved. Conducting research on early admission in colleges for cultivating vocational education teachers is to explore feasibility of early admission for vocational education teachers, making sure that better students are selected for cultivation through entrance examination so as to guarantee the quality of vocational education teachers as well as the healthy and orderly development of vocational education.

In order that researches the influence of driver factors on driving reliability under raining environment, this paper utilizes method of Principal Component Analysis to obtain representative indexes in five main driver parameters of sight, perception reaction capacity, perceptive capacity of environment, concentrating degree of attention and impatient emotion, therefore illuminates important influence of key driver factors on driving reliability. Results of case indicate that the method can effectually transform multitudinous indexes with linear correlation in influence factors set of traffic safety into representative linearly independent index variable, which provides new means for quantitative analyzing holistic reliability of driver-vehicle-environment system under complicated conditions, and provides theoretical basis for building evaluation model of driving reliability.

Collecting data of water temperature and the volume of renewable water of Xinxin board sewage treatment plant in Hohhot city Inner Mongolia Province. Obtained the rules and water temperature characteristics of renewable water and provide the basic data for the design of sewage source heat pump. Through the analysis of the capacity and taste of water, it is concluded that the renewable water of sewage treatment plant is high-quality source of sewage source heat pump.

After analyzing the highway ecosystem’s present situation and problems in current evaluation index, according to the index system’s determination principle, it establishes an evaluation index system of highway ecosystem health.

Ecological problems of highway have gradually been paid attention with highway mileage increasing rapidly. The highway ecosystem is a compound ecosystem, then it is more fragile comparing to natural ecosystem, and its healthy is stressed by both surrounding natural environment and human society. This paper describes the phenomenon of stress of highway ecosystem, analyzes the factors of stress and the influence mechanism. In addition, the development trends and stress effects are discussed.

The thesis introduces the scientific concept of highway-ecosystems, the highway -ecosystem is define as an open, dynamic, nonlinear, and complicated huge system with dissipative structures and far from equilibrium states, moreover it is a complex system of highway and ecosystem, gathering substantial cycle and ecological evolution as well as their common natural and artificial environments together. The highway ecosystem sustainable development valuation may provide the science, accurate basis and suggestion for the road ecosystem further control, and conforms to the needs of sustainable development and the building the harmonious society. Aiming at the highway eco-systems of the present sustainable development, the concept of highway-ecosystems is introduced, on the basis of detailed analyze of the concepts of multidimensional space of sustainable development system, a new multi-objective comprehensive evaluation method for sustainable development is presented and a calculation formula for multi-objective comprehensive level of sustainable development. This method was used to evaluate sustainable development of Lin-Chang Expressway. This method possessed definite theoretical value and reliability in practice.

At present, fuzzy math, grey theory which superior over other evaluation methods have been widely used in practice, but they still have some drawbacks. For a better and more comprehensive evaluation of the factors on the impact of air traffic environment, the air traffic environment impact assessment index system was established. the paper used analytic hierarchy process (AHP) and ultra-multiple method to analyze the various factors which impact the traffic atmospheric environment. It not only considered all factors in the combined effects of weight, but also highlighted the main factors in the evaluation of pollution in the main role-sharing, using arithmetic mean empowering(WZ), then based on matter-element theory, the paper proposed a new method which evaluating the traffic atmospheric environment. Through introducing the example and analyzing the results of matter-element model, fuzzy evaluation, grey evaluation, neural networks, it shows the new method is easy to use and an reasonable and accurate evaluation of the impact of air traffic environment method.

Wavefront coding technique is a powerful technique which overcomes the defects of traditional way to extend depth of field. By inserting a phase mask into the traditional incoherent imaging system, wavefront coding technique does not reduce the resolution and the light gathering power of the optical system but enlarges the depth of field of incoherent imaging system. Although several kinds of phase masks have been reported, cubic phase mask is still of a classical type which has been investigated widely both in spatial and frequency domain. Since the phase profiles of phase masks adopted in classical wavefront coding systems are predefined with specific optical systems, the extension of depth of field is not tunable. Tunable wavefront coding systems are introduced by using a pair of detachable phase masks, which is possible to control the depth of field and bandwidth of system by changing the position of each component with respect to the pupil center. Ojeda-Castaeda [Ojeda-Castaeda J, Rodrguez M, Naranjo R 2010 Proceedings of Progress in Electronics Research Symposium, Cambridge, July 58, 2010 p531] proposed to use a pair of cosine phase masks to make defocus sensitivity tunable. Zhao [Zhao H, Wei J X 2014 Opt. Commun. 326 35] investigated an improved version of Ojeda- Castaneda's design in frequency domain and found that the proposed system realized tunable bandwidth. The present study, based on the work of Zhao, analyzes the tunable characteristics of a pair of simple modified detachable cubic phase masks in spatial domain and frequency domain. Firstly, the ray aberration theory is adopted to give mathematical analyses and ray aberration maps of the proposed tunable phase mask. Based on the mathematical derivations, the size of point spread function (PSF) of system can be changed not only by profile of each cubic mask but also by the each mask displacement relative to pupil center. Secondly, a mathematical PSF based on the stationary phase method is derived in spatial domain. Simulations indicate that the positions of PSF translate in the image plane with the displacements of phase mask profile and the position of each component with respect to the pupil center. By analyzing the oscillations of PSF, the effective bandwidth is obtained. Through the expression, we can conclude that the effective bandwidth can be changed by the position, mask profile of each component and defocus. Only when the addition of two mask profiles is large enough, can the effective bandwidth be simplified without adding the influence of defocus. In addition, though the approximate expression of magnitude transfer of function (MTF) has been given by adopting stationary phase method in the appendix of previous work, it cannot give an intuitive grasp of the effective bandwidth in MTF map. Unlike the MTF expression derived before, the exact optical transfer function (OTF) expression is derived by adopting Fresnel integral in frequency domain. Exact MTF and phase transfer function (PTF) can be derived from OTF. Based on the exact MTF expression, simulations give an intuitive effective bandwidth in MTF map. Simulations also show the nonlinear property of PTF. The effective bandwidth and MTF can be changed by different phase mask profiles and positions, which indicate that the effective bandwidth and defocus sensitivity can be tuned. Analyses are conducted both in spatial domain and in frequency domain to verify the tunable property of the proposed phase mask, which provides theoretical foundation for tunable wavefront coding system design.

This paper describes the digital filtering characteristics, presents the linear phase condition of a FIR filter and its implementation, and analyses the function and its application of digital filter in a homing weapon system.

This paper describes the composition, the operating principle and the properties of a direct digital synthesizer, analyses the generating reason of DDS phase noise, studies the hardware and software designing method and engineering implementation of the signal resource for homing system test equipment implemented with the key chip AD7008.

Objective To observe the clinical effect of earlobe-bleeding plus body acupuncture for common acne. Methods The earlobe-bleeding plus local and body acupuncture based on syndrome differentiation was adopted for 85 cases of common acne. Results Of the 85 cases treated, 61 were cured, 12 markedly effective, 9 improved, and 3 failed. The total effective rate was 96.47%. Conclusions The therapy can treat both the Biao-symptom and Ben-root of common acne, short in course and effective in result.