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At present, China’s energy structure is mainly based on fossil fuels, which has brought serious problems such as environmental pollution, low energy efficiency and poor development quality. In the automotive industry, in order to save energy and protect the environment, many countries are actively promoting the production of new energy vehicles, optimizing the use of resources and benefits, and achieving green development. Based on the idea of sharing economy, this paper constructs a two-stage model. Considering the different quality of new energy vehicles in the two stages, optimization theory, game theory and other methods are used to study the influence of sharing behavior on enterprise operation decisions, and the following conclusions are drawn. First, in the presence of product sharing, product quality is negatively correlated with the optimal profit of the enterprise. Second, there is a negative correlation between the charging rate of the third-party platform and the optimal profit of the enterprise, and with the increase of the charging rate of the platform, the decline of the optimal profit of the enterprise is less and less. Third, when product sharing exists, the ratio of product quality in the two stages is positively correlated with the optimal profit of the enterprise.

The polarized energy dispersive X-ray fluorescence analysis method can effectively reduce detection limits by improving the signal-to-noise ratio. However, the lack of high-power density and small analysis area of the polarized X-ray beam has hindered more accurate analysis of samples in conventional laboratory. A polycapillary X-ray lens can be applied to micro-area analysis. Therefore, a micro-area polarized energy dispersive X-ray fluorescence spectrometer based on a bent highly oriented pyrolytic graphite and a polycapillary X-ray lens is proposed. The polarization degree of the polarized X-ray beam is 99.76% and its focal spot size is 338.8 μm × 404.5 μm. The new spectrometer feasibility was proved by effective production of high-resolution element distribution maps of a holly (Ilex chinensis Sims) leaf sample.

A simulation model is established to simulate the X-ray transmission performance through a polycapillary focusing X-ray lens whose configuration curve was described by a piecewise function. The shape of the lens is segmented, and each segment uses different function curve. The ray tracing principle is used to simulate the transmission performance of X-rays through the polycapillary focusing X-ray lens. And the simulation results were compared with the experimental results.

The different crack initiation modes from different internal defects of a high carbon chromium bearing steel are investigated in the present paper. The relative granular bright facet (GBF) size is approximately proportional to . The critical applied stress intensity factor range at the periphery of inclusion ΔKinc,th, above which the GBF will no longer be formed, was obtained. For the present SUJ2 steel, ΔKinc,th = 8 MPa m1/2. The crack growth process in GBF is further investigated by the low–high two-step variable amplitude loading tests. The crack growth process in GBF can be described by . The exponent m0 is a material constant independent of the applied stress amplitude and the inclusion size and increases with increasing of HV.

A tangential CO2 laser collective scattering system has been first installed on the Experimental Advanced Superconducting Tokamak (EAST) to measure short-scale turbulent fluctuations in EAST plasmas. The system can measure fluctuations with up to four distinct wavenumbers simultaneously ranging from 10 cm−1 to 26 cm−1, and correspondingly k ⊥ ρ s ∼ 1.5 − 4.3 . The system is designed based on the oblique propagation of the probe beam with respect to the magnetic field, and thus the enhanced spatial localization can be achieved by taking full advantage of turbulence anisotropy and magnetic field inhomogeneity. The simultaneous measurements of turbulent fluctuations in different regions can be taken by special optical setup. Initial measurements indicate rich short-scale turbulent dynamics in both core and outer regions of EAST plasmas. The system will be a powerful tool for investigating the features of short-scale turbulent fluctuations in EAST plasmas.

The crack growth process in GBF of high strength bearing steel JIS SUJ2 is qualitatively investigated by low–high two-step variable amplitude loading (TSAL) tests. It is demonstrated that the GBF size reduces with the increase in applied stress amplitude, and that the GBF size at a given stress amplitude is a constant which is independent of inclusion size at the crack origin. The fatigue life at a given stress amplitude, which is proportional to −8 power of the inclusion size, reduces with increasing inclusion size. It was shown by TSAL tests that GBF was formed at the earlier stage (approximate 105 cycles corresponding to less than 1% total fatigue life in the regime Nf≧107 cycles) and propagated hardly until near to the final life (more than 90% total fatigue life). After that the GBF crack will propagate rapidly to the ultimate size in a short time.

Zhu YM, Li YD, Colbach N, Ma KP, Wei W & Mi XC (2012). Seed losses at harvest and seed persistence of oilseed rape (Brassica napus) in different cultural conditions in Chinese farming systems. Weed Research52, 317–326. Summary This article reports experiments that explore the critical factors for gene flow in oilseed rape (Brassica napus) via the soil seedbank under Chinese farming systems. Research was carried out on 16 farmer’s fields to estimate harvest seed losses after different planting methods and harvest timings, during the four components of the harvest operations. An additional field experiment was set up to estimate the potential germination proportion of seeds in flood-irrigated and un-irrigated fields, as a function of seed burial depth over time. Seed losses were largest during the sun-drying of harvested plants in the field, accounting for about three quarters of the total seed losses. The number of intact seeds declined quickly after they entered the soil, particularly in un-irrigated fields, and no volunteers germinated in the irrigated field after 3 months. Burial depth did not affect the potential for germination and emergence of volunteers in the flood-irrigated field. However, the potential germination declined with increasing burial depth in the un-irrigated field. No viable seeds remained in the soil after 16 months. Seed losses during harvest could be limited to 0.7–1.1% by weight of total seed production by placing a plastic membrane under the cut plants during drying and no rape seeds could germinate after 3 months in water-logged condition. Thus, the risk of gene flow via the soil seedbank is probably small in Chinese oilseed rape farming systems.

Objective: We prospectively investigated the diagnostic accuracy of contrast-free 3-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) with volume rendering (VR) at 3.0 T to detect intracranial aneurysms in a large cohort of patients. Methods: We conducted a prospective clinical study including 411 patients with suspected aneurysms and other cerebral vascular diseases who were referred for contrast-free 3D-TOF-MRA at 3.0 T prior to digital subtraction angiography (DSA). 2D-DSA and VR-DSA were regarded as the gold standard. Forty-two patients were excluded. Accuracy, sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) as measures to detect or rule out intracranial aneurysms were determined by patient-, aneurysm-, vessel-, and aneurysm size–based evaluations. Results: In all 369 patients investigated, VR-DSA revealed 307 aneurysms in 246 patients (66.7%) and no aneurysm in 123 patients. The patient-based evaluation by VR 3D-TOF-MRA at 3.0 T yielded an accuracy of 97.6%, a sensitivity of 99.2%, specificity of 94.4%, PPV of 97.2%, and NPV of 98.3% in the detection of intracranial aneurysms. The aneurysm-based evaluation yielded an accuracy of 98.3%, sensitivity of 99.3%, specificity of 96.9%, PPV of 97.8%, and NPV of 99.1%. The vessel-based evaluation yielded accuracy of 98.8%, sensitivity of 99.2%, specificity of 98.5%, PPV of 97.5%, and NPV of 99.6%. The evaluation based on aneurysm sizes yielded similar results. Conclusions: VR 3D-TOF-MRA at 3.0 T accurately identified the presence of intracranial aneurysms. High PPV and NPV indicated that VR 3D-TOF-MRA at 3.0 T may replace DSA as a contrast-free, noninvasive, and non-radiation-based modality for the diagnosis and screening of intracranial aneurysms.

We describe the output performances of the 1030 nm transition in Yb:YAG under in-band pumping with diode laser at the 968 nm wavelength. An end-pumped Yb:YAG crystal yielded 1.93 W of continuous-wave (CW) output power for 9.1 W of absorbed pump power. The slope efficiency with respect to the absorbed pump power was 23.6%. Furthermore, 205 mW 515 nm green light was acquired by frequency doubling, resulting in an optical-to-optical efficiency with respect to the absorbed pump power of 2.7%. Comparative results obtained for the pump with diode laser at 940 nm are given in order to prove the advantages of the in-band pumping.

BACKGROUND AND PURPOSE: The management of intracranial pseudoaneurysms is controversial. The purpose of this study was to provide a preliminary evaluation of the clinical efficacy of a Willis covered stent specially designed for the intracranial vasculature in the management of a pseudoaneurysm of the cranial internal carotid artery (CICA). MATERIALS AND METHODS: Eight patients with pseudoaneurysms of the CICA were treated with use of the Willis covered stent. The flexibility of the entire stent system was gauged from the resistance met when reaching the target lesion and was categorized as no resistance, no apparent resistance, or resistance that could be overcome. The apposition of the Willis stent after deployment was scored as excellent with no endoleak, good with a small endoleak, or bad with an apparent endoleak. Follow-up angiography was performed 3 to 12 months after placement of the stent, and angiographic assessments were categorized as endoleak, stenosis of the covered segment of vessel, or occlusion of parent arteries. Follow-up clinical evaluations were also performed, and outcomes were graded as full recovery, improvement, unchanged, and aggravation. RESULTS: Endovascular treatment was technically successful in all aneurysms without procedural-related complications, and all of the stents were easily navigated to the targeted lesions in the CICA. Complete resolution of the pseudoaneurysm was observed in 6 patients immediately after the procedure, and a minimal endoleak into the aneurysm persisted in 2 patients. No morbidity or mortality and no technical adverse event occurred. A follow-up angiogram confirmed complete reconstruction of the internal carotid artery, with no recurrent aneurysmal filling and no occurrence of stenosis in the area of the stent. By the final follow-up visit, 4 patients had fully recovered, 3 had improved, and 1 patient9s condition was unchanged. CONCLUSION: On the basis of our preliminary experience, the Willis covered stent specially designed for the intracranial vasculature can manage a CICA pseudoaneurysm safely and effectively, but longer follow-up and expanded clinical trials are needed.

This paper presents a load impedance estimation and iterative-learning control for a three-phase four-wire inverter. The topology of a three-phase four wire inverter is adopted to uninterruptible power supply (UPS) applications, which can supply unbalanced load, linear load and rectified load. The proposed load impedance estimation scheme employs an RLC equivalent circuit concept to determine the load parameters. The inverter can track the sinusoidal reference voltage precisely and it is allowed to have wide inductance variation, reducing core size significantly. With the proposed iterative learning control, the steady-state error can be reduced significantly cycle by cycle. In the design and implementation, the inverter inductances corresponding to various inductor currents are measured off-line and tabulated into a single-chip microcontroller for tuning loop gain every switching cycle, while the RLC load parameters are estimated on-line to determine control (duty ratio), ensuring system stability. Experimental results measured from A 10 kVA system have verified the analysis and discussion.

This paper presents an iterative learning control with filter-capacitor current compensation for a three-phase four-wire inverter, which is adopted to uninterruptible power supply (UPS) applications. It can supply unbalanced, linear and rectified loads. With the proposed iterative learning control, the steady-state error can be reduced significantly cycle by cycle, and it is allowed to have wide inductance variation, reducing core size significantly. Additionally, the compensation for the filter-capacitor current is also considered in the control, which can help to shape output voltage waveform more accurately. In the design and implementation, the inverter inductances corresponding to various inductor currents are measured off-line and tabulated into a single-chip microcontroller for tuning loop gain every switching cycle, ensuring system stability. Experimental results measured from a 10 kVA inverter have verified the analysis and discussion.

SUMMARY The present study compares the efficacy of a self-expanding metallic stent (SEMS, diameter of 30 mm) and pneumatic dilation for the long-term clinical treatment of achalasia. A total of 155 patients diagnosed with achalasia were allocated for pneumatic dilation (n= 80, group A) or a temporary, 30-mm diameter SEMS (n= 75, group B). The SEMSs were placed under fluoroscopic guidance and removed by gastroscopy 4–5 days after placement. Data on clinical symptoms, complications, and long-term clinical outcomes were collected, and follow-up observations were performed at 6 months and at 1, 3–5, 5–8, 8–10, and >10 years, postoperatively. Pneumatic dilation and stent placement were technically successful in all of the patients. There were no significant differences in technique success, 30-day mortality, or complications between the two groups. The clinical remission rate in group A was significantly lower than that in group B at 1, 1–3, 3–5, 5–8 and, >10 years (P < 0.05), while the cumulative clinical failure rate in group A (66%, 53/80) was higher than that in group B (92%, 6/75). The mean primary patency in group B was significantly longer than that in group A (4.2 vs 2.1 years, respectively; P < 0.001). A temporary, 30-mm diameter SEMS was associated with a better long-term clinical efficacy in the treatment of patients with achalasia as compared with treatment with pneumatic dilation.

BACKGROUND AND PURPOSE: The carotid siphon is a natural barrier to intracranial interventions. Our aim was to make a model of the human intracranial internal carotid artery (ICA) and to test the navigability of covered stents for intracranial applications. MATERIALS AND METHODS: A digital tube was made on the basis of raw MR images of the human ICA. It was transferred into 10 physical models and then coated with silicone by using a 3D rapid prototyping (RP) machine. Ten dogs then underwent surgery. Their common carotid arteries (CCAs) were exposed, cut, and passed through 1 of the tubes. Finally, the vascular models were made by reanastomosis of their CCAs. Eight expended polytetrafluoroethylene (e-PTFE) covered stents (two 3.5 × 16 mm, two 3.5 × 13 mm, two 3.5 × 10 mm, and two 3.5 × 7 mm) were implanted 1 week later. Two dogs remained as controls. The performance of the device was evaluated by angiography and histopathologic examination. RESULTS: Ten animal models were successfully constructed. There was no vascular spasm or thrombosis when assessed by angiography. Destruction of the tunica intima and media was found in the 3.5 × 16 mm stent group. Destruction of the endothelium was found in the 3.5 × 13 mm stent group, and only flattening of the endothelium was found in the 3.5 × 10 mm and 3.5 × 7 mm stent groups. CONCLUSIONS: The experimental model was thought to simulate adequately the geometry of the human ICA and, thus, would be an effective tool for the research and testing of neurovascular devices. The length of the stent is 1 factor influencing the navigability in tortuous vessels.

Aims: To investigate the early pattern of longitudinal change in forced expiratory volume in 1 second (FEV1) among new Chinese coal miners, and the relation between coal mine dust exposure and the decline of lung function. Methods: The early pattern of lung function changes in 317 newly hired Chinese underground coal miners was compared to 132 referents. This three year prospective cohort study involved a pre-employment and 15 follow up health surveys, including a questionnaire and spirometry tests. Twice a month, total and respirable dust area sampling was done. The authors used a two stage analysis and a linear mixed effects model approach to analyse the longitudinal spirometry data, and to investigate the changes in FEV1 over time, controlling for age, height, pack years of smoking, mean respirable dust concentration, the room temperature during testing, and the groupxtime interaction terms. Results: FEV1 change over time in new miners is non-linear. New miners experience initial rapid FEV1 declines, primarily during the first year of mining, little change during the second year, and partial recovery during the third year. Both linear and quadratic time trends in FEV1 change are highly significant. Smoking miners lost more FEV1 than non-smokers. Referents, all age less than 20 years, showed continued lung growth, whereas the miners who were under age 20 exhibited a decline in FEV1. Conclusion: Dust and smoking affect lung function in young, newly hired Chinese coal miners. FEV1 change over the first three years of employment is non-linear. The findings have implications for both methods and interpretation of medical screening in coal mining and other dusty work: during the first several years of employment more frequent testing may be desirable, and caution is required in interpreting early FEV1 declines.

An electromagnetic wave coherent scattering system has poor longitudinal spatial localization. However, considering the spatial variation of magnetic field lines and the perpendicularity of the short-scale turbulence to these magnetic field lines, we may be able to obtain spatially localized turbulence measurements. In this paper, we first describe the method and simulation results for localized turbulence measurements by a laser () collective scattering diagnostic on the HT-7. Second, we study the performance of electron density fluctuations between channel 1 ( ) and channel 2 ( ) during sawtooth activities. After a sawtooth crash, the signals of channel 1 change considerably and the signals of channel 2 remain nearly the same; cross-correlations between the two channels are very low (≈0.1). These experimental results verify that our laser collective scattering diagnostic does have some spatial resolution on HT-7.

Pattern recognition is demonstrated using two-dimensional nonlinear optical logic gate arrays on ZnS and ZnSe interference filters defined by fly's eye lens arrays. Fan-out is demonstrated, allowing symbol scription using these arrays.