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As a core component of the bucking coil helicopter transient electromagnetic (TEM) system, the current pulse inverter should agree two crucial aspects, high power and fast turn- OFF . In this article, based on the design and modeling of transmitting coil and bucking coil, a novel current inverter topology based on the double constant voltage clamping technology, which differs from the traditional single clamping technology is firstly proposed and analyzed. By using double clamping technology, both the current pulse's rising edge and falling edge are improved effectively. What's more, the turn-OFF time of the current inverter is adjustable, which is of great difference from the conventional clamping technology with nonadjustable turn-OFF time. The ground and field experiments are implemented to test the performance of the current inverter. The results of the ground test of the performance comparison with worldwide VTEM transmitter verify that it successfully converts the standard 28 V dc source from helicopter power to bipolar approximately trapezoid pulses with a peak current of 300 A and a much faster turn-OFF time than the VTEM transmitter. The results of field exploration further demonstrate that it achieves a high quality of primary field compensation and effectively improve the detection capability of the helicopter TEM surveying system.

In this paper, we propose a terahertz (THz) spiral spatial filtering (SSF) imaging method that can enable image contrast enhancement. The related theory includes three main steps: (1) the THz image of the target is Fourier transformed to the spatial spectrum distribution, (2) the spatial spectrum is modulated by a spiral phase at the Fourier plane, (3) the filtered spatial spectrum is inverse Fourier transformed to the desired THz image. Meanwhile, analytic expression of the final THz image is derived. Due to the unique nature of the spiral phase, THz image contrast enhancement can be achieved and verified by various simulated target images with different contrasts. In our designed THz SSF imaging system, Fourier transform is carried out by the lens, and the spiral phase is acquired by the spiral phase plate (SPP). Proof-of-principle experiments with three different types of targets (carved metal letters, a high-density polyethylene (HDPE) piece with a scratch, and a leaf) were carried out, and the effectiveness of contrast enhancement and edge extraction on the THz reconstruction images was validated.

BACKGROUND: We conducted a phase I clinical trial that infused CCR5 gene–edited CD4(+) T cells to determine how these T cells can better enable HIV cure strategies. METHODS: The aim of trial was to develop RNA-based approaches to deliver zinc finger nuclease (ZFN), evaluate the effect of CCR5 gene–edited CD4(+) T cells on the HIV-specific T cell response, test the ability of infused CCR5 gene–edited T cells to delay viral rebound during analytical treatment interruption, and determine whether individuals heterozygous for CCR5 Δ32 preferentially benefit. We enrolled 14 individuals living with HIV whose viral load was well controlled by antiretroviral therapy (ART). We measured the time to viral rebound after ART withdrawal, the persistence of CCR5-edited CD4(+) T cells, and whether infusion of 10 billion CCR5-edited CD4(+) T cells augmented the HIV-specific immune response. RESULTS: Infusion of the CD4(+) T cells was well tolerated, with no serious adverse events. We observed a modest delay in the time to viral rebound relative to historical controls; however, 3 of the 14 individuals, 2 of whom were heterozygous for CCR5 Δ32, showed post-viral rebound control of viremia, before ultimately losing control of viral replication. Interestingly, only these individuals had substantial restoration of HIV-specific CD8(+) T cell responses. We observed immune escape for 1 of these reinvigorated responses at viral recrudescence, illustrating a direct link between viral control and enhanced CD8(+) T cell responses. CONCLUSION: These findings demonstrate how CCR5 gene–edited CD4(+) T cell infusion could aid HIV cure strategies by augmenting preexisting HIV-specific immune responses. REGISTRATION: ClinicalTrials.gov NCT02388594. FUNDING: NIH funding (R01AI104400, UM1AI126620, U19AI149680, T32AI007632) was provided by the National Institute of Allergy and Infectious Diseases (NIAID), the National Institute on Drug Abuse (NIDA), the National Institute of Mental Health (NIMH), and the National Institute of Neurological Disorders and Stroke (NINDS). Sangamo Therapeutics also provided funding for these studies.

Dynamically changing machining conditions and uncertain manufacturing resource availability are forcing manufacturing enterprises to search advanced process planning in order to increase productivity and ensure product quality. As growing quantities of the three-dimensional process models are gradually applied, reusing the embedded manufacturing information in process models with less time and lower cost attracts a lot of attention. In this paper, a new flexible method is presented to reuse the existing process information based on retrieval of the similar machining feature. First, the three-level organization model is introduced to represent the process information; the machining feature which is seen as the parent layer carries the corresponding manufacturing information. To ensure accurately that the process information are obtained, the associated mechanism between the machining feature and process information is created. Second, an eight-node representation scheme is designed to represent the similar machining feature having same variations in topology and geometry. For accelerating similar feature retrieval, the extension-attributed adjacency graph and the topological relationship of the machining feature faces are built. Finally, some aircraft structural parts are utilized in the developed prototype module to verify the effectiveness of the proposed method. This method can be used as the basis for accumulation of the process information; it can promote the development and application of the intelligent process planning.

A new type of pulmonary sequestration ventilator was used to compare the relationship between controlled lung collapse and early lung injury in thoracic surgery for dogs. Eighteen experimental dogs were randomly divided into three groups (G1-G3 groups). After general anesthesia, the shunt balance in lung was controlled and the pulmonary sequestration tube was placed in the femoral artery and vein, and the Swan-Ganz tube was placed into the right internal jugular vein as well. Two-lung ventilation (TLV) was first performed for 20 min, followed by one-lung ventilation (OLV). The degree of collapse was 100% (G1), 90% (G2), and 50% (G3). Blood samples were extracted from femoral artery and jugular vein prior to collapse (T0), and at 30 (T1), 60 (T2), and 120 (T3) min after collapse for blood gas analysis to determine the shunt ratio (Qs/Qt). Blood samples were also subjected to enzyme linked immunosorbent assay (ELISA) to determine serum tumor necrosis factor-α (TNF-α), intercellular immune adhesion molecule-1 (ICAM-1) and interleukin-6 (IL-6) levels. Arterial blood pressure, heart rate, pulmonary artery pressure and other physiological indicators were monitored during the experiment. Lung tissues were collected at T3 to calculate the wet/dry weight ratio (W/D). Histopathological changes were observed and compared by microscopic observation and blind scoring of pathological section after hematoxylin and eosin (H&E) staining. There were no significant differences in the physiological indexes between the two groups during TLV (P>0.05). Mean pulmonary arterial pressure (MPAP) in G2 and G3 groups was significantly more stable than that in G1 group after OLV (P0.05). Compared with complete lung collapse (collapse degree: 100%), controlled lung collapse (collapse degree: 90% and 50%) can better reduce the intraoperative lung injury, but there was no significant difference between the collapse degrees of 90 and 50%.

Presented in the paper is the design, the simulation, the fabrication and the experiment of a new z-axis resonant accelerometer based on the electrostatic stiffness. The new z-axis resonant micro-accelerometer, which consists of a torsional accelerometer and two plane resonators, decouples the sensing movement of the accelerometer from the oscillation of the plane resonators by electrostatic stiffness, which will improve the performance. The new structure and the sensitive theory of the acceleration are illuminated, and the equation of the scale factor is deduced under ideal conditions firstly. The Ansys simulation is implemented to verify the basic principle of the torsional accelerometer and the plane resonator individually. The structure simulation results prove that the effective frequency of the torsional accelerometer and the plane resonator are 0.66 kHz and 13.3 kHz, respectively. Then, the new structure is fabricated by the standard three-mask deep dry silicon on glass (DDSOG) process and encapsulated by parallel seam welding. Finally, the detecting and control circuits are designed to achieve the closed-loop self-oscillation, to trace the natural frequency of resonator and to measure the system frequency. Experimental results show that the new z-axis resonant accelerometer has a scale factor of 31.65 Hz/g, a bias stability of 727 µg and a dynamic range of over 10 g, which proves that the new z-axis resonant micro-accelerometer is practicable.

This paper presents a numerical study on the structure optimization of a full-sized floating liquefied natural gas (FLNG) membrane tank. When floating with partially filled liquid, impact pressure on boundaries plays an important role in the sloshing membrane tank. Modification of bottom structure can lead to various pressure distributions on the tank bottom and sidewalls. The optimization is studied by carrying out the numerical simulations and particularly focusing on the structure of sloped-bottom. The applied CFD package, FLOW-3D 10.1, solves the Navier-Stokes equations with the standard k-ε turbulence model and Volume-of-Fluid method to describe the free surface movement. The numerical result is validated against the experimental data and numerical result from the Smoothed Particle Hydrodynamics method. Liquid behavior is investigated in four different tanks. A modified method using average value of fluid peak depth is applied to locate the natural sloshing frequency. The greatest local pressure was approximately 65 KPa near the intersection of slope and bottom. The comparison of peak pressure indicates that tank with 15% width sloped-bottom has smaller affected area of high pressure and lowest value of peak pressures, which is the optimized sloped-bottom tank in pressure performance. The outcomes from the numerical simulation are expected to be a reference data for the design of FLNG cargo containment system.

Photoacoustic (PA) tomography (PAT) has potential for use in brain imaging due to its rich optical contrast, high acoustic resolution in deep tissue, and good biosafety. However, the skull often poses challenges for transcranial brain imaging. The skull can cause severe distortion and attenuation of the phase and amplitude of PA waves, which leads to poor resolution, low contrast, and strong noise in the images. In this study, we propose an image reconstruction method to recover the PA image insider a skull-like scattering layer. This method reduces the scattering artifacts by combining a correlation matrix filter and a time reversal operator. Both numerical simulations and PA imaging experiments demonstrate that the proposed approach effectively improves the image quality with less speckle noise and better signal-to-noise ratio. The proposed method may improve the quality of PAT in a complex acoustic scattering environment, such as transcranial brain imaging.

PKU-FEL based on superconducting (SC) accelerator facility is under construction at PekingUniversity. It will run in IR (5 - 10 μm) and THz (100 - 3000 μm) region as an ideal experimental FEL platform for universities. The SC accelerator facility is composed of a DC-SC injector and a 1.3-GHz 2 × 9-cell SC accelerator. In order to better the performance, the injector and the accelerator are bath-cooled by 2 K super fluid helium in cryostats. A 2 K cryogenic system has been designed, constructed and assembled.

For surface texture measuring instruments, the embedded analysing and evaluating software is as important as its hardware for accurate and integral performance. To evaluate the precision and correctness of the software, software measurement standards have been proposed in ISO 5436-2 (2001). As the traditional hardgauge specimens, which are used to calibrate the instrument hardware, the software measurement standards were designed for calibrating the software of the instrument. In this paper, the software measurement standards, including two types of standards Type F1—reference data, Type F2—reference software and data file formats of Type F1, are described. Their recent developments worldwide are reviewed, and differences among software measurement standards for the surface texture developed by different organizations are compared and analyzed in the light of a practical application example of the standards. (PACS, Measurement Science and Technology)

This study described an index of aspartate aminotransferase-to-platelet ratio index (APRI) to assess hepatic fibrosis with limited expense and widespread availability compared to the liver biopsy in adolescent patients with CHB.

The strategy of storage and organization can be adjusted utilizing the access and distribution law of the spatial data, which will significantly improve system performance of spatial data services. The access and distribution law of the spatial data based on Hotmap and Zipf-like are statics, and can not reflect its global information real-time. A dynamic statistical method based on collaborative cloud is proposed in this paper to resolve above-mentioned problems. The nodes service capabilities are calculated in our algorithm. The node agents with good service capabilities are chosen preferentially in the group to fuse dynamic statistical information. The experimental results show that the performance of our algorithm can be improved by about 29% compared with the algorithm of random nodes. The algorithm can meet the need of dynamic statistics in large scale cloud mode with high efficiency.

The financial crisis of 2007 to the present highlights the importance of banks operating risk management, while screening mechanism is a key issue for banks risk control within an innovative supply chain finance (SCF). From the angle of commercial banks, this paper explores the interior mechanism of SCF and then uses fuzzy synthetic evaluation method, combining with meta-graphs to make a tentative investigation of screening mechanism of small and medium size enterprises.

As a newly developing mode, BT mode is not a way of project contracting but a mode of investment and financing. The adoption of BT mode facilitates the development of urban infrastructure, and brings in economic benefits for the enterprise. But the lack of legal basis arose new problems, therefore the project management and analysis of financing risk under BT mode will be the key to bringing BT mode into operation.

Standing at the whole socio-economic level where the construction projects locate, this thesis took the construction projects as a compounding system of natural-social-economic and researched the apply of project management in sustainable development. First, from the respect of management object, project attribute, management goal, management organization and so on, it has compared the project management in sustainable development and the traditional project management; Next, it has discussed the goal system of the project management in sustainable development. The project management in sustainable development must achieve not only the basic goal (cost, quality and progress) of project, but also the social responsibility goal, the environment and development goal as well as the sustainable development, thus to solve the questions of environment and development and realize sustainable development; Finally, it proposed implementation process of the project management in sustainable development, and put forward several feasible advice on the management of projects.

To multi-objective decision-making problems of Enterprise project investment, this paper analyzed the issues in project decision, considered the factors of qualitative and quantitative in the project decision, and combined with the various constraints of the project selection process, then established the objective planning model of enterprise project investment and discussed the application of the model. The paper proposes applying the 80/20 principle to choice evaluation objectives, and using simplified scoring method to dealing with those qualitative goals.

Pilling image segmentation is a key step in the objective evaluation system of fabric pilling level. The traditional methods of pilling segmentation apply to only one or more fabrics. In order to improve the properties of the evaluation system, an algorithm based on edge flow is proposed in this paper. The algorithm makes use of a prediction model to identify the image color or direction change of image texture in the given scale, and an edge flow vector is generated. The edge points of image are detected through the propagation of edge flow vector. The algorithm is proved to have strong adaptability and better effect for more fabric pilling images through the experiments.

Based on image processing technology, this paper constructs a fabric-pilling evaluation system in which the edge flow method is used to implement pilling segmentation of complex fabrics. Then the system extracts three characteristic parameters: the number of pilling, total area of pilling and optical volume of pilling and describes the relationship between grades. Finally, in the three-dimensional space, the grade evaluation of fabric pilling is implemented by use of the least distance method. Experiments on various fabric-pilling images show that the system has extensive applicability and good result.

Comprehensive tradeoff control on quality, construction duration, cost and resource equilibrium is main aspect of construction project management, and is significant for improving the benefits of construction projects. In this paper, firstly the time-cost relationship model, the quality-time relationship model and resource equilibrium-time model are set up separately, objectives of quality and resource equilibrium are introduced to traditional time-cost optimization model for comprehensive optimization. Furthermore, multiple objective model of schedule is established by synthesizing single-objective models of quality and resource equilibrium. Then, based on TOPSIS, comprehensive optimization scheme is selected according to relative approach degree. Finally a case study is presented to verify feasibility and practicability of method.

Magnetic anomaly detection (MAD) is an effective method for the detection of ferromagnetic targets against background magnetic fields. Currently, the performance of MAD systems is mainly limited by the background geomagnetic noise. Several techniques have been developed to detect target signatures, such as the synchronous reference subtraction (SRS) method. In this paper, we propose an adaptive coherent noise suppression (ACNS) method. The proposed method is capable of evaluating and detecting weak anomaly signals buried in background geomagnetic noise. Tests with real-world recorded magnetic signals show that the ACNS method can excellently remove the background geomagnetic noise by about 21 dB or more in high background geomagnetic field environments. Additionally, as a general form of the SRS method, the ACNS method offers appreciable advantages over the existing algorithms. Compared to the SRS method, the ACNS algorithm can eliminate the false target signals and represents a noise suppressing capability improvement of 6.4 dB. The positive outcomes in terms of intelligibility make this method a potential candidate for application in MAD systems.

This paper focuses on the design of the master control software dedicated for the application of high-resolution polar detection ice radar. The central part of proposed software is FPGA, which plays roles of collecting radar echo data, playback of chirp signal, data transmission to upper computer, coherent integral accumulation of digitized data and system control of the whole radar system. The performances of proposed system is demonstrated through real-field experiments.

Objectives To determine the prevalence of physiological valvular regurgitation in Chinese and analyse the distribution characteristics of physiological pulmonary regurgitation (PR) in the crowd. Methods 1750 subjects without cardiac diseases from Qilu Hospital of Shandong University were chosen to be examined by echocardiography. All physiological valvular regurgitation was recorded. The characteristics of physiological PR observed from colour-Doppler echocardiography were recorded. The maximum regurgitation pressure of physiological PR was measured by continuous-wave Doppler. Results The prevalence of physiological PR was 30.86%, which was the highest in the crowd and followed by tricuspid regurgitation 14.63%, mitral regurgitation 7.37% and aortic regurgitation 2.06%. The distribution of physiological PR in the crowd was as follows. It was much higher in young subjects less than 20 years old and elders more than 60 years old ( P P > 0.05). Meanwhile, the prevalence of physiological PR in subjects with tricuspid regurgitation (TR) was 39.06%, which was higher than the overall prevalence ( P Conclusions Of all physiological valvular regurgitation physiological PR was most commonly seen. It had its own characteristics observed from Doppler echocardiography and its distribution in the crowd was special. The maximum regurgitation pressure may be used as a reference for the diagnosis of physiological PR.

Objective The inflammatory response and the long-term endothelium healing after drug-eluting stent (DES) placement has recently emerged as a major concern. We investigated the change of metabolic parameters and systematic inflammatory status of circulating mononuclear cells (MNC) in patients after coronary DES implantation. Methods 27 patients with non-ST segmental elevation acute coronary syndrome that had undergone DES implantations were consecutively recruited and administrated with standard drug therapy for 12 weeks. The systematic inflammation on MNC was measured before DES implantations and after 12 weeks’ medication. NF-κB binding activity in MNC and expression of its subunits p65 and p50, and depressed cytosolic IκB expression of MNC were detected to reveal the systematic inflammation after DES implantations. Results Metabolic parameters total cholesterol, triglycerides, HDL, LDL improved significantly after 12 weeks’ standard medication, but plasma concentrations of interleukin-6, tumour necrosis factor-α, migration inhibitor factor, and matrix metalloproteinase-9 increased compared with baseline (p=0.012, 0.035, 0.062 and 0.112, respectively). The NF-kB DNA binding activity in MNC increased significantly compared with baseline (p=0.015), concomitantly with decreased IκB-β (p=0.052) and PPAR-γ in MNC (p=0.002). Although there were strong correlations within the change of metabolic parameters and within the change of proinflammatory factors, no significant correlations between them were observed. Conclusions Standard drug therapy can improve metabolic parameters, but fail to restrain the deteriorated systemic inflammatory responses prolonged at least 3 month. These findings raise concern about the efficiency of the current standard therapy in the era of DES. However, longer term endpoint-based studies are necessary to further explore the relationship between the inflammatory factors and the clinical cardiovascular events.

This paper introduces a systematic, structure-based modeling framework for analysis and control of electric power systems for processes evolving over the mid-term and long-term time horizons. Much simpler models than the detailed dynamics specifically for control design at different hierarchical levels are obtained by applying both temporal and spatial separation. These simple models, or the aggregate models, represent the net effect of interactions among interconnected regions on specific hierarchical levels. They are exact, since no assumptions on weak interconnections among the subsystems are made. Moreover they are easily understood in terms of power flows among the regions. The approach is essential for improving present performance of the system. It is also potentially useful in a competitive utility environment in which it is critical to study the interplay between technical and economic processes., United States. Dept. of Energy (Office of Utility Technology, grant DE-FG41-92R1104447)