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In the process of improving coalbed permeability through pulse hydraulic fracturing, the cyclic loading effect influences the characteristics of micropores in coal matrix, thus affecting the process of gas migration. Therefore, it is essential to investigate the effect of cyclic loading on the pore structure of coal. Seven groups of loading tests at different frequencies and amplitudes were conducted on anthracite coal obtained from Shanxi Province, China, using a fatigue-testing machine. Subsequently, using a PoreMaster GT-60 Mercury-intrusion apparatus, the influence of the frequency and amplitude on the structural characteristics (including mercury-injection and mercury-ejection curves, pore size distribution, porosity, and specific surface area) of pores in coal samples was analyzed. Finally, the law and mechanism of action of the loading frequency and amplitude on pores in coal samples were comprehensively analyzed. The test results showed that, in the case of maintaining the sine-wave amplitude unchanged during loading while altering the loading frequency, the overall porosity and pore volume rise at different degrees. The growth of the loading frequency presents a more significant promotive effect on the initiation and development of pores and fractures. Moreover, it drives the transformation of micropores and transition pores into mesopores and macropores, thus increasing the proportion of seepage pores. Under the condition of large sine-wave amplitude during loading, macropores and mesopores are subjected to the repeated action of the external force, thereby reducing the overall porosity. In addition, the volume of the seepage pores declines, and the number of the coalesced pores decreases. Finally, in light of these results, the implications of frequency and amplitude selection in the process of pulse hydraulic fracturing are discussed. Therefore, the results of this research will provide an important theoretical basis for the field application of pulse hydraulic fracturing technology in coal mines.

The development of thermoelectric measurement technology at nanoscale is a challenging task. Here, a novel MEMS-based dual temperature control (DTC) measurement method for thermoelectric properties of individual nanowires was proposed. Different from conventional thermal bridge testing devices, this DTC thermoelectric testing device can obtain the thermoelectric properties by independently control ambient temperature and temperature difference between two ends of the nanowires through two separate resistance thermometers without auxiliary heating devices. The reliability of the model and the testing accuracy were verified by accurately measuring the thermal conductivity, electrical conductivity, and the absolute value of the Seebeck coefficient of VO2 nanowires.

Our previous investigation suggested that faster seventh cervical nerve (C7) regeneration occurs in patients with cerebral injury undergoing contralateral C7 transfer. This finding needed further verification, and the mechanism remained largely unknown. Here, Tinel's test revealed faster C7 regeneration in patients with cerebral injury, which was further confirmed in mice by electrophysiological recordings and histological analysis. Furthermore, we identified an altered systemic inflammatory response that led to the transformation of macrophage polarization as a mechanism underlying the increased nerve regeneration in patients with cerebral injury. In mice, we showed that, as a contributing factor, serum amyloid protein A1 (SAA1) promoted C7 regeneration and interfered with macrophage polarization in vivo. Our results indicate that altered inflammation promotes the regenerative capacity of the C7 nerve by altering macrophage behavior. SAA1 may be a therapeutic target to improve the recovery of injured peripheral nerves.

Background and purpose: Digital subtraction angiography (DSA), a minimally invasive procedure for an exceptional visualization of cerebrovascular angioarchitecture, has become an important imaging technique for inclusive evaluation and therapeutic embolization. Our purpose is to share the importance of DSA for evaluation of cerebral aneurysms. Material and method: A total of 148 patients with suspected intracranial aneurysm underwent digital subtraction angiography during January 2005 to December 2009. Preliminarily aortogram was considered in old age group (>50yrs) before supra-aortic angiography. Patient’s selection criterion included both ruptured and unruptured aneurysms. 3D rotational effect was applied for all complex cerebral aneurysms with unfavorable dome neck ratio. DSA was accomplished into 2- 6 standard projections for every vascular territory for optimal visualization and accurate evaluation of cerebral aneurysms. Result: 21 were males and 48 were females. Age difference was ranged between 26-78 years with an average of 51.5years. Among 288 patients, total detected aneurysms were 480. 32 presented with SAH, 21 presented with headache and 14 patients came with cranial nerve dysfunction during admission. 3 had negative angiography irrespective to spontaneous subarachnoid hemorrhage. Delineation of aneurysmal neck improved with rotation effect of 3D DSA in 80% of patients. Parent vessel and its relationship to adjacent vessels was better demonstrated with rotational angiography in >50% of cases. Endovascular embolization was done in 80 patients in same setting. Conclusion: DSA with 3D rotational technique is an essential radio-imaging tool for accurate characterization of cerebrovascular diseases and subsequently beneficial to elaborate on their potential treatment protocols.

Warranty is an important means for the Chinese army to introduce maintenance resources from private contractors. In order to optimize the ship warranty system of the Chinese Navy, this paper analyzes the problems and defects of the current ship warranty system of the Chinese Navy, and then explores the optimization path of the ship warranty system of the Chinese Navy combined with the ship warranty practice of the armed forces in Taiwan and abroad. The research shows that there are many hidden dangers in the short warranty period for ships. Prolonging the warranty period of ships can bring important military benefits and promote the generation and maintenance of the combat effectiveness of the fleet. The relevant academic departments of the Chinese Navy should carry out the demonstration and Optimization Research on the warranty period of ships as soon as possible.

BackgroundIn spite of the important role of Apolipoprotein-M (ApoM) and Sphingosine-1-Phosphate (S1P) played in atherosclerosis (AS), there was few related research reporting ApoM and S1P complex (ApoM-S1P) on biological activities of human umbilical vein endothelial cells (HUVECs). In this study, we explored the effect and mechanism of ApoM-S1P on TNF-α-induced inflammation in HUVECs.MethodsTNF-α was utilized to induce HUVEC injury and inflammation. After HUVECs were treated with antagonists of ApoM, S1P, ApoM + S1P, and ApoM + S1P + S1PR, calcein-acetoxymethyl ester was employed for the assessment of the adhesion of HUVECs to THP-1, immunofluorescence for the observation of caspase-1expression in HUVECs, reactive oxygen species (ROS) kit for the detection of ROS level in HUVECs. The impact of TNF-α, ApoM, S1P and S1PR antagonists on inflammatory response, pyroptosis and adhesion of THP-1 monocytes to HUVECs were determined by detecting expressions of pyroptosis related proteins (IL-1β, IL-18, ASC, NLRP3 and caspase-1), inflammatory cytokines (IL-6 and IL-10), adhesion molecules (E-selectin, ICAM-1, and VCAM-1) and p-PI3K/p-AKT by qRT-PCR and Western blot, as well as by ELISA.ResultsTNF-α could increase adhesion of THP-1 monocytes to HUVECs and induce inflammatory response and pyroptosis in HUVECs, indicated by up-regulated expressions of E-selectin, ICAM-1, VCAM-1, IL-1β, IL-18, caspase-1, ASC, NLRP3, and IL-6, and down-regulated expression of IL-10. Co-treatment of ApoM-S1P on TNF-α treated HUVECs could protect HUVECs from injury and inflammation, evidenced by the attenuation of expressions of pyroptosis related proteins, inflammatory cytokines, and adhesion molecules, as well as the augment of PI3K and AKT phosphorylation. JTE-013, an antagonist of S1PR2, could reverse the amelioration of ApoM-S1P on pyroptosis and inflammation of HUVECs, indicating that ApoM-S1P could bind to S1PR2 to protect HUVECs from injury and inflammation through activating PI3K/AKT pathway.ConclusionApoM-S1P could attenuate TNF-α induced injury and inflammatory response in HUVECs by binding to S1PR2 to activate PI3K/AKT pathway.

With large scale renewable power integrating, hybrid power system needs joint optimization dispatching. Considering complementary characteristics of different power types, this paper first constructs a day ahead time scale optimized dispatching model. The objectives are minimizing the system operation cost and maximizing the renewable energy consumption. The startup-stop status of thermal units and power output of different type power stations are selected as optimization variables. The problem then is modeled as a multistep Markov decision process which is a sequential decision process problem. A reinforcement learning method, Deep Deterministic Policy Gradient algorithm, is introduced to solve the decision problem. Finally, simulations have been carried out to validate the effectiveness of the proposed method. Numerical results show that the proposed method obtains a satisfied result which can meet the power load demanded, ensure the consumption of renewable energy and minimize the system cost meanwhile.

Background Spastic limb paralysis due to injury to a cerebral hemisphere can cause long-term disability. We investigated the effect of grafting the contralateral C7 nerve from the nonparalyzed side to the paralyzed side in patients with spastic arm paralysis due to chronic cerebral injury. Methods We randomly assigned 36 patients who had had unilateral arm paralysis for more than 5 years to undergo C7 nerve transfer plus rehabilitation (18 patients) or to undergo rehabilitation alone (18 patients). The primary outcome was the change from baseline to month 12 in the total score on the Fugl–Meyer upper-extremity scale (scores range from 0 to 66, with higher scores indicating better function). Results The mean increase in Fugl–Meyer score in the paralyzed arm was 17.7 in the surgery group and 2.6 in the control group (difference, 15.1; 95% confidence interval, 12.2 to 17.9; P

Background Orthokeratinized odontogenic cysts (OOCs) are uncommon intraosseous cystic lesions and are distinguished as an individual entity of odontogenic cysts in the new World Health Organization classification. Objective To analyze the clinicopathologic features of OOC in a Chinese population. Methods All cases reported as OOCs and odontogenic keratocysts (OKCs) were reviewed from the files of the Department of Oral Pathology, Peking University School and Hospital of Stomatology, from 2000 to 2018. We identified 144 OOC cases and analyzed clinical and pathological information. Results In the present study, we report the largest series of OOC cases, to our knowledge. There were 98 male and 46 female patients with a peak incidence in the third to fourth decades of life. One hundred thirty-six cases (94.4%) were solitary, and 8 cases (5.6%) were multiple. The most common sites were in the mandibular molar and ramus region. Radiographically, 12 lesions showed multilocular radiolucency with bone destruction, whereas others were unilocular. All the cases were primary. In follow-up of 116 patients, 114 were treated by simple enucleation, which revealed no recurrence over a period of 0.5-17 years after surgery. Compared with OKCs, OOCs revealed different histologic and immunohistochemical features. Conclusions OOC is clinicopathologically distinct from OKC and should constitute its own clinical entity according to histologic features and biologic behavior. Further study is needed to investigate the pathogenesis and mechanism of OOCs.

Background: Primary dysmenorrhea (PD) is a functional disease of the female reproductive system, which has adverse effects on patients’ physical and mental health and quality of life. At present, acupoint application of traditional Chinese medicine (TCM) as adjuvant therapy is undergoing clinical trials in different medical centers. However, there is no systematic review or meta-analysis to evaluate the efficacy of acupoint application of TCM in the treatment of PD. There is also a lack of systematic evaluation and analysis of acupoints and herbs. Methods: All randomized controlled trials related to acupoint catgut embedding therapy on PD will be searched in the following electronic databases: Cochrane Central Registry of controlled trials, PubMed, Wed of Science, EMBASE, Science Net, China Biomedical Literature Database, China Science Journal Database, China National Knowledge Infrastructure and Wan-Fang Database, from inception to May, 2021 were searched without language restrictions. The primary outcomes contain visual analog score, The Cox Menstrual Symptom Scale, while the secondary outcomes consist of adverse events and the recurrence rate. Two reviewers will independently perform data selection, data synthesis, and quality assessment. Data meeting the inclusion criteria will be extracted and analyzed by Revman v.5.3 software. Two reviewers will evaluate the study using the Cochrane collaborative bias risk tool. We will use the scoring method to assess the overall quality of the evidence supporting the main results. We will also use Spass software (version 19.0) for complex network analysis to explore the potential core prescription of acupoint application of traditional Chinese medicine in the treatment of PD. Results: This study will analyze the clinical effective rate, functional outcomes, quality of life, improvement of clinical symptoms of PD, and effective prescriptions of acupoint application for patients with PD. Conclusion: Our findings will provide evidence for the effectiveness and potential treatment prescriptions of acupoint application for patients with PD. PROSPERO registration number: CRD 42021244357

For high-proportional wind power access to power grids, how to coordinate the energy storage switching strategies with other various power generation energy sources is the key to the effective utilization of energy storage and the improvement of wind power consumption. This paper proposed a safety barrier that power grid established through energy storage for eliminating wind power, studied evaluation and identification methods of energy storage input, and established the model of energy storage operation and the relationship between energy storage capacity and wind power consumption demand energy storage capacity and clean energy consumption demand. It also constructed a method for analyzing the correlation between electric heating thermal storage load and abandonment wind during heating period, and explored the qualitative relationship between abandoned wind power, abandoned wind hours and abandoned wind power. However, the energy storage capacity is configured according to the maximum abandonment power, and the energy storage efficiency is not high, and the wind power that is consumed by the electric heating thermal storage load is the abandoned wind power during the heating period.

Large-scale clean energy is merged into the power grid. For different grid-connected methods, the reasons for wind abandonment are different. In this paper, it studied peak-regulated wind abandonment and grid frame abandoned wind, and proposed the calculation model and discrimination method of the peak-regulated wind abandonment and grid frame abandonedwind; it also proposed the correlation analysis method of power grid wind abandonment, peak-regulated wind abandonment and grid frame abandoned wind. Combined with the example, the paper analyzedthe relationship between power grid wind abandonment, peak-regulated wind abandonment and grid frame abandoned wind. For the northern heating season, the peak-regulated wind power abandonment is larger. In the non-heating season, the grid frame abandoned wind power is larger, and when the peak-regulated wind power abandonment is larger, the grid frame abandoned wind power is smaller, and the duration of the peak-regulated wind abandonment is smaller than the duration of the grid frame abandoned wind. Because a large number of measures to consumption wind are mainly aimed at peak-regulated wind abandonment, the proportion of grid frame abandoned wind has exceeded 1/3 of the total abandoned wind. It can be seen that the research on abandoning wind should be carried out from the two dimensions of peak-regulated wind abandonment and grid frame abandoned wind.

Aiming at the randomness and volatility of the abandoned wind with high proportion wind power connected to the large power grid, this paper proposed a the entire processes accurate evaluation analysis method with multi-dimensional, multi-period and multi-type, constructed a multi-dimensional analysis system such as electricity, hours, abandonment rate and abandonment ratio, and constructed a multi-period analysis system such as the annual, heating season, monthly and hourly electricity distribution and the corresponding low valley period, it also constructed a multi-type analysis system such as peak shaving abandoned wind and grid structure abandoned wind, which provides a theoretical basis for implementing large-scale abandoned wind consumption. Combined with the actual examples, the abandoned wind analysis system established in this paper has practical significance for mastering the law of abandoning wind and selecting appropriate measures for abandoning wind consumption.

We proposed contralateral cervical seventh nerve transfer for spastic arm paralysis after central neurological injury in the New England Journal of Medicine (NEJM) in 2018. In this surgery, we applied a new surgical route for nerve transfer, the Huashan prespinal route. The objective of this study was to elaborate our new surgical technique, clarify its relationship to the vertebral artery, and provide anatomical data on this novel method. The effectiveness and safety of the Huashan prespinal route in contralateral C7 nerve transfer were evaluated anatomically. Nine cadavers (4 males, 5 females) were available for this study. Among these, anatomical parameters of the vertebral artery were obtained from 6 cadavers, and the anastomosis of the bilateral cervical seventh nerve was observed on 3 cadavers undergoing contralateral C7 nerve transfer via the Huashan prespinal route. Tension-free anastomosis of the bilateral cervical seventh nerve was achieved through the Huashan prespinal route. The tilt angle of the vertebral artery to the sagittal plane (with thyroid cartilage as the origin) was 25.5 ± 4.5°, at 22.5 ± 1.6° and 28.7 ± 4.3° on the left and right side, respectively. The safe drilling angle to penetrate through the longus colli muscles for the creation of a longus colli muscle tunnel to avoid injury to the vertebral artery in our surgical technique was above 33.2°. The cadaveric study confirms that the presented technique allowed simple, effective, and safe contralateral C7 nerve transfer. This technique can be used in the treatment of hemiplegia and brachial plexus injury. There is a safe scope of drilling angle for creating the longus colli muscle tunnel required for this surgical route. The anatomical parameters obtained in this study will be helpful for the performance of this operation.

A common method for the treatment of sports injuries for a long time to provide localized cooling in ice or snow is fomentation. This system will support a feature extraction cloud computing platform application of localized cooling which is applied to the shape of ice snow for treatment of sports injuries. It is a common method of treatment of sports injuries. Athletes usually utilizes the application of therapeutic hypothermia to return to athletic activities.. Two review authors have independently assessed the relevance and impact calculations involved in the trial, and the cloud worker permits the highlights removed legitimately from the scrambled picture. Awareness of disability sport, in particular para snowboard, may not be common or easily available, so it is important that these potential athletes know that the sport exists and where they can try the sport for the first time Some examination and test results show that, for protection trademark picture extraction, proposed technique is successful, safe, and it might be applied to the cloud picture secure figuring applications.

In the economic dispatch and optimal operation of power system, it is necessary and effective to consider the correlation among heat load, power load and wind power output to formulate a reasonable dispatch plan or to evaluate the reliability of the system. Therefore, based on the theory of Copula correlation analysis, a multivariate Copula analysis toolbox (MvCAT) is proposed to infer Copula parameters and estimate potential uncertainties. Firstly, the mixed evolution Markov Chain Monte Carlo (MCMC) method in Bayes framework calculates the posterior distribution of Copula parameters, evaluate their uncertainties relative to fitting, and then select the appropriate Copula function by goodness-of-fit test. Finally, a the typical daily data of a province as samples for analysis, proposed method solves the limitation that the local optimization method often falls into the local minimum, and quantitative evaluation of the correlation between the response variables and the uncertainty associated with the length of the recorded data is essential for multivariate frequency analysis.

On 1st December 2017, the world's largest 100MW/129MWh lithium battery storage power station from Tesla was put into operation in South Australia. Then on 14th December 2017 and 18th January 2018, Tesla storage battery participated in grid frequency recovery after Victorian Loy Yang power station unit tripping accident. Tesla was triggered 140ms after the accident, before injecting active power to the grid. As a result, grid frequency was back to 50Hz with the help of Tesla and other contracted coal-fired generators within 6 minutes. Up to now, Tesla power station has provided auxiliary services such as regular adjustment and output, energy output and emergency output to the power grid. This paper first analyzes the physical and economic reasons why Tesla storage battery is integrated into Australia power grid. Then the structure and control strategy of battery is introduced. The operation of energy storage is introduced from both physical and economic dimensions. Later on, energy storage grid related technical standards and evaluation hierarchy are suggested to be made. New type of ancillary service is developed and storage’ s profit making mode is explored. All above proposals are lessons that China should learn to develop its storage technologies and storage-grid integration technologies.

Intrusion target detection and recognition are of great significance to security protection of oil and gas fields. An intrusion detection system is built with the integration of infrared image acquisition module, infrared image processing module, moving target detection module and recognition module. Traditional target recognition algorithm highly relies on manual design feature extraction algorithm, which requires designer to have adequate prior knowledge, and cannot avoid the influence of subjective factors of people. Intrusion detection and target recognition system are proposed based on deep learning, which uses neural network algorithm. Deep learning model is built through feature extraction and training of acquired images of intrusion objects, and thus subsequent invasion objects are detected and recognized. Intrusion detection is achieved through simulation of human brain, which boasts of more intelligent recognition process and more accurate recognition results compared with traditional recognition method. According to applications in real scenario, the system proposed has better detection and recognition results and great practical value.

In this paper, computational fluid dynamics software to simulate three-dimensional flow of marine propeller applications was introduced and described the 3D-CAD model building process, complex moving mesh division methods of the region, three-dimensional rotating turbulence model selection and analysis of the results. Visual image obtained the pressure distribution, flow velocity distribution of the marine propellers, and focused on analyzing the reasons for producing results.

In the traditional discriminative object tracking methods, similar to the target, background is often taken mistakenly as a single negative class to train two-class classifiers despite including various objects with different distributions. A novel method based on one-class classifier is proposed for object tracking. It takes background as a collection of all other classes except the target. Object tracking is viewed as a one-class classification problem correspondingly. Firstly, the tracking results in the recent few frames are collected as the target training samples. Secondly, a k-nearest-graph is built based on these training samples and the most representative samples are selected on the basis of their own local average degrees to construct a minimum spanning tree. Then an one-class classifier based on the minimum spanning tree is trained to model the target. Lastly the similarity scores of candidates drawn from a particle filter are evaluated by the trained one-class classifier and the one with highest score is taken as the tracking result in current frame and used to update the training sample set and the one-class classifier. Empirical results on challenging video sequences demonstrate the superior performance of our method in robustness and accuracy to state-of-the-art methods.

With the installed capacity of Liaoning's wind power reaching 8 million kW, wind turbines' daily maximum load and generating capacity repeatedly set new records now and then, which have some impacts on Liaoning's power grid in terms of peak regulation, voltage stability and frequency control. This paper starts from the characteristics of wind power and wind resource in Liaoning province. It brings forward some concrete measures in light of the operating conditions of Liaoning Power grid, which guarantee operational security and stability of the power grid while improving the grid's wind power accommodation capacity as much as possible.

This paper introduces the occurrence, the development and the recovery process of 11.7 Liaoning Power Grid blackout accidents. Since it bears many resemblances to 3.4 accident of Liaoning Power Gird in 2007 in terms of cause, location, treatment and influence, this paper analyses this two accidents from the aspects of region, meteorology, devices, grip structure and social impacts. Thus, some characteristics of power girds' frozen accidents of South Liaoning are summarized and suggestions on the operation of power girds are bring forward.

Statistically, power grid accidents are inevitable. The larger the scale of a power grid, the more probably a power grid accident will occur. Preventing a power grid accident as soon as possible from occurring and handling the accident in a most efficient and quick way are two important topics to power grid dispatchers. This paper analyses in detail the causes of grid accidents such as tripping of above 220 kV lines of Liaoning Power Grid using big data statistics method, and finds some objective laws, which would help Liaoning Power Grid and other power grids in safe operation and scientific management.

The detection and identification of the kinds of ships, i.e., warship or merchant ship, is of great interest for military use. Ships are usually detected and recognized based on ship physical fields, and the commonly used ship physical fields include sound field, magnetic field, hydraulic pressure field, electric field, gravity field, etc, which all contain plenty of discriminative information. However, the existing ship identification methods are usually based on single ship physical field, which will limit the model performance. In this work, we proposed a ship recognition method based on combination of multi-physical fields, i.e., sound field and magnetic field. To the best of the authors' knowledge, this is the first work to recognize ships based on multi-physical fields. We fuse features extracted from multi-physical fields by Principal Component Analysis (PCA), which is then fed to Support Vector Machine (SVM) to realize the recognition of ship. Plenty of experiments demonstrate the effectiveness of the proposed method.

Gd2-xEux(MoO4)3 red phosphors are synthesized by using co-precipitation method.X-ray diffraction(XRD),scanning electron microscopy(SEM) and fluorescence spectrum are used to characterize the structure and luminescent property of the samples.The luminescent properties of Gd2-xEux(MoO4)3 with various concentration of Eu3+ are investigated in detail.The results show that three dominant bands locate at 394,465,534 nm.The emission spectra exhibit the most intense emission at 589 nm and 613 nm,especially the later which is corresponding to the 5D0→7F2 transition of the Eu3+.With the increase of the concentration of Eu3+,the luminescent intensity of the phosphors is gradually increased.When x=0.6(i.e.Gd1.4Eu0.6-(MoO4)3),the luminescent intensity of the red phosphor is the strongest.

As a kind of clean energy, wind power has gained rapid development in recent years. Liaoning Province has abundant wind resources and the total installed capacity of wind power is in the forefront. With the large-scale wind power grid-connected operation, the contradiction between wind power utilization and peak load regulation of power grid has been more prominent. To this point, starting with the power structure and power grid installation situation of Liaoning power grid, the distribution and the space-time output characteristics of wind farm, the prediction accuracy, the curtailment and the off-grid situation of wind power are analyzed. Based on the deep analysis of the seasonal characteristics of power network load, the composition and distribution of main load are presented. Aiming at the problem between the acceptance of wind power and power grid adjustment, the scheduling strategies are given, including unit maintenance scheduling, spinning reserve, energy storage equipment settings by the analysis of the operation characteristics and the response time of thermal power units and hydroelectric units, which can meet the demand of wind power acceptance and provide a solution to improve the level of power grid dispatching.

Large-scale access of distributed power can improve the current environmental pressure, at the same time, increasing the complexity and uncertainty of overall distribution system. Rational planning of distributed power can effectively improve the system voltage level. To this point, the specific impact on distribution network power quality caused by the access of typical distributed power was analyzed and from the point of improving the learning factor and the inertia weight, an improved particle swarm optimization algorithm (IPSO) was proposed which could solve distributed generation planning for distribution network to improve the local and global search performance of the algorithm. Results show that the proposed method can well reduce the system network loss and improve the economic performance of system operation with distributed generation.

Ship target detection and recognition have great application value for military use. However, developing such a system is always challenging, and one main reason is the lack of data. Ship's physical fields, e.g., Sound filed, magnetic field and hydraulic pressure field, contain discriminative information, and we need lots of data of ship physical field signals to learn an effective classifier. In this paper, we are going to develop models and simulations for three kinds of ship physical fields such as sound filed, magnetic field and hydraulic pressure field. The proposed system can not only simulate independently, but also accomplish the physical fields of ships at the time and point. The system could also display real time simulation graphics automatically.

Online discriminative learning methods have been shown to give promising results in visual tracking. However, the shortage of positive examples representing the object can degrade the classifier. To handle this problem, we propose a l 1 -graph based semi-supervised object tracking algorithm, which make full uses of the intrinsic manifold structure of the dataset including both labeled and unlabeled instances to obtain a better classifier. We first extract positive and negative examples as labeled templates from the previous few frames and draw candidates with a particle filter. Then the l 1 -graph is constructed based on all templates and candidates. The similarities between the templates and candidates are evaluated over l 1 -graph. Lastly, the tracking result is employed to update the l 1 -graph. Empirical results on challenging video sequences demonstrate the superior performance of our method in robustness and accuracy to state-of-the-art methods in the literatures.

An optical wavelength demultiplexer with the etched diffraction grating (EDG) on the silicon-on-insulator (SOI) material is demonstrated. Fabricated by the wet-anisotropic-etching method, 90° turning mirrors are used to bend waveguides, and the size of the EDG-based demultiplexer is minimized to only 16×2.5 mm2. The crosstalk is below −16 dB. The on-chip loss is about 9.97 dB, which is composed of about 8.72 dB excess loss and 1.25 dB diffraction loss. The polarization-dependent central wavelength shift is below 0.13 nm, and the polarization-dependent loss is about 0.35 dB. The sources of the crosstalk and loss are discussed in details, and the related measures to improve the performance are also presented.

Nanoscale vacuum electronics has been receiving much attention recently with the design and fabrication of vacuum field emission transistors and other devices. The performance and lifetime of these devices depend on the material choice for the emitters. Silicon carbide is a robust material with appealing work function and established fabrication processes. Field emission properties of SiC nanoemitters under different cathode–anode gaps are studied in this work with the aid of focused ion beam etching to control the gap precisely. When the electrode gap is as small as 20 nm, a considerable decrease in voltage and increase in field emission current are seen. When the electrode gap is decreased progressively, the emission current increases exponentially at a fixed collector voltage, and the absence of current saturation is ideal for device scaling. Simulations and Fowler–Nordheim equation are used to analyze the field emission characteristics. The emission is enhanced for both extremely short gaps and sharp ...

The aim of the study was to explore the effect of birdpecking and revolving moxibustion on twelve back shenshu points on the bone metabolism and bone histomorphometry of osteoporosis rats. The 50 female rats of 8 months old that did not pregnant were collected and randomly divided into sham-operation group, model group, moxibustion group, moxibustion and estrogen group, and estrogen group. All the rats, except for the rats in the sham-operation group, received ovarian surgery to establish the models. After 10 days postoperatively (healing), the rats received moxibustion and estrogen therapy. According to the different groups, the rats received rat femur in vivo bone mineral density assessment at 90 days after surgery. After that, the rats were sacrificed, and then the left femoral bones were collected for bone histomorphometry test; blood was taken for bone alkaline phosphatase (BALP) testing, and urine was collected for hydroxyproline testing. The urine hydroxyproline was tested once at 24 h after ovarian surgery. At 24 h after ovarian surgery, the urine hydroxyproline in the ovariectomy group was significantly higher than that in the sham-operation group (P < 0.05), indicating that after ovarian surgery, the collagen broke down which accelerated the process of osteoporosis. After the intervention therapy with moxibustion and estrogen, the BALP, urinary hydroxyproline and femoral bone histomorphometry were comparatively analyzed, and the results showed that the intervention groups were higher than the model group (P < 0.05). But when compared with the sham-operation group, the indexes in the intervention groups were decreased, and the differences were significant (P < 0.05), indicating that intervention could only delay the incidence of osteoporosis. The Chinese traditional measure of "birdpecking and revolving moxibustion on twelve back-shu points" can effectively prevent the recession of bone metabolism of osteoporosis rats, and slow down the degeneration of bone morphology, which can be used to delay the incidence of osteoporosis.

Reconstruction of liquid free slosh modes by curved quiet free surface was investigated in the case of small Bond number by means of modal part analysis method in this paper. It is shown that the curved liquid quiet free surface would couple the modes to form new eigen-modes while the orthogonality of the modes which participate the liquid slosh are given only by their Bessel modal parts and it would change their eigen-frequencies respectively while the orthogonality are given by their triangle function modal parts. By studying the laterally forced slosh of the liquid in a cylindrical container based on the new eigen-modes, a characteristic of modeschoosing was found.

A compact optical demultiplexer with etched diffraction grating (EDG) is designed and fabricated on a silicon-on-insulator (SOI) material. Several 90? turning mirrors are used to bend the waveguides, and the size of the EDG-based demultiplexer is minimized to only 16?1.7?mm2. The crosstalk is about -18?dB. The on-chip loss is about 18.2?dB, which is composed of about 16.9?dB excess loss and 1.3?dB diffraction loss. Measures to improve the performance are discussed.

In this paper, multi-disciplinary theory and the "discarded, and innovation" speculative view on the history of Traditional Ethnic Minority Sports Development, present and future development of the plight of the three dimensions of the problems. Put forward the guidance of scientific outlook on development to meet the needs of modern self-development and social development as the goal, attention to the content transmission mechanism and the coordinating role of culture, and gradually build diversified development modes for, designed to Traditional Sports " globalization "the development of the context of operational results, so that the save" nationality ", based on active participation in the world sports culture of dialogue and exchange, and fitness with Chinese characteristics, system and building a harmonious society to play a more for the active and important role.

Soft starters is necessary for dc motors for its big starting current. This paper presents a novel neuro fuzzy based dc voltage controller which modulate the pulses width of the IGBT when the motor is starting. An ANFIS (Adaptive Neuro Fuzzy Inference System) model has been designed to achieve the proposed algorithm. MATLAB/SIMULINK package has been used to simulate the proposed method. Simulation results presented in this paper explain the advantages of proposed soft starting method over conventional method. The advantages of proposed method are its simplicity, stability, and accuracy and fast response.

In this paper, a Code-Orthogonalized Transmitted- Reference impulse-based UWB system is proposed based on the time-delay and frequency-shifted transmitted-reference impulse- based UWB system. Mathematic derivation and simulation results show that this system has better performance and needs no analog delay element compared with time-delay Transmitted- Reference system, and thus lends itself to miniaturization system design. Compared with Frequency-Shifted Transmitted- Reference system, the performance of this system does not worsen obviously along with the increase of multi-path delay and data rate, which makes it suitable for higher data rate and longer transmission distance.

In this paper, we present a novel technology to realize a doubly clamped nanobeam, which is preferred to cantilever because of its higher natural frequency with a same dimension, as a piezoresistive mass sensor. Ar selective bombardment was applied on a 200 nm thick doubly clamped nanobeam to form a piezoresistor in a Wheaston bridge along with other ordinary resistors. The device was electrostatically actuated and readout piezoresistively. The achieved merit product of Q-factor and f0 in air is as high as 3.5 times 108 , which hints a better mass detection resolution compared with its counterpart of micro cantilever, while our approach is simple and easily controlled.

In order to implement the function of the large capacity Li-dynamic battery forming power, a discharge circuit was added into the main circuit of the analog battery charger based on integrated power modules. DSP was used to substitute the initial ancillary circuit. A new control algorithm using bi-loop control structure with dead zone non-linearity characteristic was presented in this paper to fulfill the constant current charge followed with constant voltage charge process. A feed-forward plus feedback control making up for the effect of the time-variable model of the discharge circuit was proposed to fulfill the constant current discharge control. Experiments showed that the system had high precision, fast response speed, no collision during response process and strong network building capability, which satisfied the requirement of the large capacity Li-dynamic battery forming power.

Superconducting quantum interference device (SQUID) amplifier is best known for its low input impedance, low noise and low power consumption. Nowadays it is widely used for detecting the weak signals. Compared with other methods, the Nb/Al-AlOx/Nb structure Josephson junction based SQUID has the advantages of high transition temperature, high voltage flux modulation index and good heat recycle ability, wide critical voltage range, so it is a very good option for making SQUID amplifier. In this work, we fabricate the overdamped Josephson junction and washer dc SQUID, and test the I-V characteristics at He3 3 K stage temperature and calculate the current resolution of SQUID. The result of SQUID modulation property is good. The magnification becomes larger after increasing the input line number of loops, and the system noise becomes smaller after the join of the LC filter. This work is very important for designing and manufacturing transition edge sensor readout circuits.

In this paper, based on the inductively coupled plasma (ICP) etching and KOH wet etching techniques, the fabrication of integrated waveguide turning mirror (IWTMs) is presented.

Planar lightwave circuits based on silicon are playing important roles in integrated optical systems. Integrated waveguide turning mirror (IWTM) is essential component for the compactness of optical devices. We design an integrated waveguide turning mirror with a 90 degree(s) directional change in SOI, which diminishes the primary loss from the displacement of waveguide and mirror and has very low mirror surface roughness. In this paper, the theory, design and fabrication of this IWTM are introduced. A beam splitter using the structure is fabricated to test the performances, and expected results are obtained.

Nanoscale refinement on a (100) oriented silicon-on-insulator (SOI) wafer was introduced by using tetra-methyl-ammonium hydroxide (TMAH, 25 wt%) anisotropic silicon etchant, with temperature kept at 50 °C to achieve precise etching of the (111) crystal plane. Specifically for a silicon nanowire (SiNW) with oxide sidewall protection, the in situ TMAH process enabled effective size reduction in both lateral (2.3 nm/min) and vertical (1.7 nm/min) dimensions. A sub-50 nm SiNW with a length of microns with uniform triangular cross-section was achieved accordingly, yielding enhanced field effect transistor (FET) characteristics in comparison with its 100 nm-wide pre-refining counterpart, which demonstrated the feasibility of this highly controllable refinement process. Detailed examination revealed that the high surface quality of the (111) plane, as well as the bulk depletion property should be the causes of this electrical enhancement, which implies the great potential of the as-made cost-effective SiNW FET device in many fields.

We develop a solar simulator composed of multiple xenon arc lamps combined with a faceted paraboloidal dish concentrator to drive a Stirling engine in our laboratory for all-weather indoor testing. Experiments and numerical analysis are performed to determine the radiation flux and temperature distributions on the solar receiver surface. Based on the theoretical results, we present a receiver design for a solar Stirling engine with involute tubes closely conforming to the imaginary hemisphere to obtain a substantially uniform temperature field and a high solar-thermal efficiency of 67.1%.

A turning mirror is a key component in compact optical waveguide devices and high-density integrated optics. An improved two-step method for fabrication of high-quality, compact turning mirrors in silicon-on-insulator materials is proposed. First, inductively coupled plasma etching is applied to produce the turning mirror, which keeps the turning mirror compact; then silicon wet anisotropic etching is applied to enhance the quality of the turning mirror by of its polishing surface, correcting its orientation, and improving the verticality. The shape of the turning mirror fabricated by the two-step method is hexagonal or octagonal, matching the optical field of the rib waveguide well. A large effective mirror size to reflect light waves and reduced shrinkage of the mirror size during etching guarantee that a mirror produced by this two-step method will be more compact than previously designed mirrors.

Background It has been widely demonstrated that the hedgehog pathway is strongly associated with basal cell carcinoma of the skin (NBCCS). To assess potential DNA alterations related to keratocystic odontogenic tumors (KCOTs), we sequenced smoothened (SMO) genes in 12 sporadic KCOTs. Methods Polymerase chain reaction (PCR), capillary electrophoresis and dideoxy chain-termination sequencing were used to examine potential DNA alterations in sporadic KCOTs. Results Five alterations in SMO genes were detected. Four of these mutations consisted of two synonymous and three missense mutations; two of which have not been reported to date (c.T776A, c.T1281G). Conclusions SMO genes may play an important role in the sonic hedgehog (SHH) pathway and could also be responsible for generating KCOTs and NBCCS. However, their influence on SHH signaling remains to be elucidated.