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Raising the pressure rank of axial piston pumps is an effective way to enhance the power density. However, when hydraulic fluid switches between the suction and discharge areas in the valve plate at a high level of pressure, the effective delivery flow rates of pumps decrease and may cause vibrations, noise and gaseous cavitation. Increasing the inlet pressure is a common method used to reduce gaseous cavitation; however, this requires additional equipment to pressurize the inlet line, which reduces the power density of the pump. This study proposed a new approach to reduce gaseous cavitation by modifying the shape of the unloading holes for pumps. A computational fluid dynamics (CFD) model was established to examine the influences of the unloading holes of the valve plate on gaseous cavitation. The simulation results revealed that a crescent-shaped unloading hole in the valve plate can effectively decrease the gaseous cavitation by redistributing the damage power of cavitation. Moreover, the crescent-shaped design of the unloading hole can increase the unloading rate by 64.39% at an inlet pressure of 1.1 MPa and rotational speed of 1600 r/min compared to that of traditional unloading holes. As a result, cavitation in the pump can be reduced effectively by an improved unloading rate, which has great practical significance for suppressing the cavitation phenomenon and decreasing vibration and noise in the pump.

It is a research hotspot to restore decoded videos with existing bitstreams by applying deep neural network to improve compression efficiency at decoder-end. Existing research has verified that the utilization of redundancy at decoder-end, which is underused by the encoder, can bring an increase of compression efficiency. However, most existing research neglects the abundant multi-scale information among video frames as a typical type of such redundancy. It remains an interesting yet challenging topic how to build an effective, interpretable and fast deep neural network for the purpose of using the multi-scale similarity at decoder-end and further enhancing compression efficiency. To this end, this paper considers the use of underused inter multi-scale information and proposes the Fast Multi-Scale Deep Decoder (Fast MSDD) for the state-of-the-art video coding standard HEVC. The advantages of Fast MSDD are three-fold. First, it achieves a higher coding efficiency without modifying any encoding algorithm. Second, Fast MSDD is interpretable based on the framework of using the underused redundancy. Third, it guarantees the model's inference speed while fully using the multi-scale similarity among video frames. Extensive experimental results verify Fast MSDD's effectiveness, interpretability, and computational efficiency. Fast MSDD obtains averagely 14.3%, 10.8%, 8.5% and 7.6% BD gains for AI, LP, LB and RA respectively. Compared with our previous work MSDD, Fast MSDD achieves increases of 59.3%, 49.1%, 61.0% and 29.3%. Meanwhile, 16.9%, 11.2%, 9.2% and 8.3% BD gains are observed on videos with scale changes, which validate the interpretability of the proposed method. Furthermore, Fast MSDD can save at most 56.3% time compared to MSDD.

YTaO4 and the relevant modification are considered to be a promising new thermal barrier coating. In this article, phase stability and mechanical properties of the monoclinic (M), monoclinic-prime (M′), and tetragonal (T) REMO4 (M = Ta, Nb) are systematically investigated from first-principles calculations method based on density functional theory (DFT). Our calculations show that M′-RETaO4 is the thermodynamically stable phase at low temperatures, but the stable phase is a monoclinic structure for RENbO4. Moreover, the calculated relative energies between M (or M′) and T phases are inversely proportional to the ionic radius of rare earth elements. It means that the phase transformation temperature of M′→T or M→T could decrease along with the increasing ionic radius of RE3+, which is consistent with the experimental results. Besides, our calculations exhibit that adding Nb into the M′-RETaO4 phase could induce phase transformation temperature of M′→M. Elastic coefficient is attained by means of the strain-energy method. According to the Voigt–Reuss–Hill approximation method, bulk modulus, shear modulus, Young’s modulus, and Poisson’s ratio of T, M, and M’ phases are obtained. The B/G criterion proposed by Pugh theory exhibits that T, M, and M’ phases are all ductile. The hardness of REMO4 (M = Ta, Nb) phases are predicted based on semi-empirical equations, which is consistent with the experimental data. Finally, the anisotropic mechanical properties of the REMO4 materials have been analyzed. The emerging understanding provides theoretical guidance for the related materials development.

Sarcopenia is age-related, pathophysiological muscle atrophy. Research regarding nutrition treatment of sarcopenia has developed rapidly, particularly as populations age. We evaluated the development of trends in this field using a bibliometric analysis. Articles up to July 2022 were searched in the Scopus database. Bibliographic information from the selected publications, such as countries, citations, world maps, institutions, authors, journals, and keywords, were converted and analyzed automatically using the “bibliometrix” package in R environment (version 4.2.0). We identified 368 Scopus articles from 1998–2021. According to citation analyses, 27 documents received more than 100 citations. Bibliometric analysis based on the literature included in this study revealed that South Korea (61 publications), United States (50), Japan (35), China (30), and Italy (20) contributed the most publications. Tehran University of Medical Science (19 records, 2.55% of articles) contributed the most publications. The most productive author was Landi, with eight articles (2.17% of articles). The publications were located in 196 journals, with Nutrients having the most publications (30, 8.15% of articles). The curves representing keywords “sarcopenia” and “aged” were the most apparent. Our analysis suggested that global nutrition and sarcopenia-related research increased rapidly from 2001 to 2021, demonstrating that this was a promising area of future research that could benefit from continued advances. Future research may focus on the effects of age and sex as well as intervention effectiveness, particularly exercise and nutrition supplementation.

Introduction: China continues to rank among one of the countries with the highest number of tuberculosis (TB) cases globally. Migrants are a particularly at-risk subgroup for TB and pose a challenge for case management in contemporary China. The early diagnosis and treatment of patients with TB are pivotal for effective TB control. This study investigates the delay in the TB diagnosis of migrants as compared with residents, to provide an evidence base for improved case detection and the better management of migrant patients with TB.Materials and Methods: The data was collected from the Tuberculosis Information Management System (TBIMS) (2015–2019) in an eastern county of China. The total diagnostic delay, consisting of patient delay and health system delay, is defined as the interval between the onset of TB symptoms and the confirmation of TB diagnosis in the designated TB hospital. The comparison of the delay in the TB diagnosis between migrants and residents was conducted using a Mann-Whitney U-test and chi-square test. The difference in the delay curves between these two groups was examined using a log-rank test.Results: Of 2,487 patients with TB, 539 (22%) were migrants. The migrants tended to be younger, presented with less severe conditions, received an initial diagnosis at prefectural and above-level hospitals. Compared with the local patients with TB, the migrant patients with TB had a longer median total diagnostic delay (30 vs. 9, P = 0.000) and a higher proportion of patients with this delay >28 days (52 vs. 13%, P = 0.000). Similarly, the migrant patients with TB also had a longer median patient delay (13 vs. 9, P = 0.000) and a higher proportion of patients with this delay >14 days (47 vs. 30%, P = 0.000), longer median health system delay (9 vs. 0, P = 0.000), and a higher proportion of patients with this delay >14 days (42 vs. 0.5%, P = 0.000) than the local patients with TB. The survival curves of delay showed that the longer the time interval was, the more likely the migrant patients with TB were to be diagnosed (P < 0.05).Conclusions: Diagnosis is significantly delayed among migrant patients with TB. Our study highlights the importance of early screening and diagnosis for TB especially among migrants, to improve access and ensure better management for all patients with TB.

BACKGROUND Sensorineural hearing loss is caused by defects in the inner ear. In the present study, associations between chronic rhinosinusitis, outer hair cell injury, and sensorineural hearing loss were investigated. MATERIAL AND METHODS A total of 103 patients who met the inclusion criteria were recruited and allocated into a chronic rhinosinusitis group (n=82) and a simple deviated nasal septum group (n=21). Degree and type of hearing loss, including distortion product otoacoustic emissions, were used to assess the status of cochlear outer hair cells. RESULTS The rate of hearing loss in the simple deviated nasal septum group was significantly lower than in the chronic rhinosinusitis group (4.76%, 1/21 vs. 24.39%, 20/82, P

In the high-power dissipation devices, the demand for thermal solutions has been increased over the period. Over time, heat sinks have been the most preferable thermal solution to many applications but are still limited to provide better thermal conductivity in high power applications. Instead vapor chambers provide even better thermal conductivity than copper. The thermal conductivity of copper is 231 Btu/hr-ft-F or 385 Watts/mk which is higher than all other metals except silver and diamond. In this paper, the latest vapor chamber design has been introduced using aluminum casing. The design structure uses a stack of 1mm fin plates connected to the vapor chamber in order to offer much better thermal conductivity. The thermal conductivity of aluminum is 235 Watts/mk which is less than copper but it is economical. The results of the thermally tested vapor chamber are added in this paper to provide a better understanding of the vapor chamber.

Background: External auditory canal (EAC) cholesteatoma (EACC) is rare and its treatment for different lesions has not yet been standardized.Objective: This study aimed to explore the clinical feat...

This paper will demonstrate the design technique for LED lighting control using the Power Line Communication (PLC) technology based on the research. LEDs today are the most preferred lighting source due to their low power, high-efficiency and smaller size. Power lines used universally and are a generally accessible communication medium for PLC technology. In this paper, a master and slave architecture are presented which makes use of the half duplex communication where the master unit generates the data pulses and slave receives these pulses at a rate of 1 Kb/s to control the LEDs connected through the driver unit. This device is having ability to control more than one slave using the single master controller. The results have been added to show the successful communication established between the master and slave units. The proposed method is less expensive due to least circuitry and a simple design using half duplex communication. No complex protocols like ethernet employed in this design method.

In order to explore the corrosion and protection methods of casing used in CO2-riching block deep oil and gas wells, CO2 development wells, CO2 storage wells, we used high-temperature and high-pressure corrosion instrument and SEM to detect the form of corrosion product film and corrosion rate. We analyzed the basic principle of CO2 corrosion on casing steel and the influence of temperature and CO2 partial pressure on corrosion rate. We also established mathematical model for calculation and analysis of corrosion rate. The result shows that the corrosion product layer consists of three layers of films with different microstructures; the temperature and CO2 partial pressure affect the casing corrosion rate by affecting the chemical reaction process and the corrosion product film formation mechanism; the composition of the casing material, temperature, CO2 partial pressure conditions are different, the degree of change in the corrosion rate of the steel is different; when the temperature increases, the corrosion rate of N80 and J55 casings decreases, while the corrosion rate of P110 casing increases; the partial pressure of CO2 increases, and the corrosion rate of steels generally increases; the corrosion resistance of J55 steel in three casing grades is relatively strong, increasing the Cr content in the steel can effectively improve the corrosion resistance of the steel. The above research system reveals the law and mechanism of CO2 corrosion in down-hole casing under high-temperature and high-pressure conditions and establishes a corrosion rate calculation model suitable for higher temperature and pressure conditions, which provides a basis for reasonable determination of corrosion protection measures.

As we all know, there is strong multi-scale similarity among video frames. However, almost none of the current video coding standards takes this similarity into consideration. There exist two major problems when utilizing the multi-scale information at encoder-end: one is the extra motion models and the overheads brought by new motion parameters; the other is the extreme increment of the encoding algorithms’ complexity. Is it possible to employ the multi-scale similarity only at the decoder-end to improve the decoded videos’ quality, i.e., to further boost the coding efficiency? This paper mainly studies how to answer this question by proposing a novel Multi-Scale Deep Decoder (MSDD) for HEVC. Benefiting from the efficiency of deep learning technology (Convolutional Neural Network and Long Short-Term Memory network), MSDD achieves a higher coding efficiency only at the decoder-end without changing any encoding algorithms. Extensive experiments validate the feasibility and effectiveness of MSDD. MSDD leads to on averagely 6.5%, 8.0%, 6.4%, and 6.7% BD-rate reduction compared to HEVC anchor, for AI, LP, LB and RA coding configurations respectively. Especially for the videos with multi-scale similarity, the proposed approach obviously improves the coding efficiency indeed.

Based on the considerations of an additional angle on the swashplate, the inertia of moving slippers and pistons, the offset between cylinder barrel axis and swashplate rotating axis, the offset between piston ball center and swashplate reference plane, the driving torque model by all slippers on swashplate of the aeronautical hydraulic axial piston pump is created. The numerical calculation for a certain pump is taken as an example. From the result, ignoring inertial force can cause obvious calculation error for the torque. If the offsets are rationally designed, the slippers driving toque can rotating the swashplate to larger angle positon. If the swashplate is rotating, the rotating speed can affect the average value of the slippers driving torque.

In order to determine the method of protecting the cement sheath structural integrity in oil and gas wells, the finite element mechanics models of the Casing-Cement sheath-Stratum Combination Body (CCSCB) were established based on different stratum action mechanism. The effect of stratum type, well depth, crustal stress and stratum elastic modulus on the interface stress and structural integrity of cement sheath were researched. The results show that, in the creep stratum, the interface contact pressure of cement sheath increase and the circumferential stresses reduce with the increase of crustal stress. There is no effect of the crustal stress on the interface stress in the elastic and rigid stratum. In elastic stratum and low crustal stress creep stratum, circumferential tensile stress would be generated at cement sheath when loading. The cement sheath is easy to crack by this tensile stress and the structural integrity is destroyed when the load was higher. The effect of stratum elastic modulus on the interface stress is related to the stratum and stress type. There is no influence of the elastic modulus on the interface stresses in the rigid stratum. The influence of the elastic modulus on the interface contact pressure is obvious in the elastic stratum, and the effect on the circumferential stress is obvious in the creep stratum.

Objectives To describe a clear and simplified classification system for juvenile nasopharyngeal angiofibroma (JNA), and to describe suitable management options. Study design Retrospective medical record review. Methods The clinical and imaging materials of 51 cases of JNA diagnosed at our hospital between 1981 and 2011 were collected and studied. Based on our experiences, we prefer to divide JNAs into three types. Type I includes JNAs fundamentally localized to the nasal cavity, paranasal sinus, nasopharynx, or pterygopalatine fossa. Type II is a JNA extending into the infratemporal fossa, cheek region, or orbital cavity, with anterior and/or minimal middle cranial fossa extension but intact dura mater. Type III is a calabash-like massive tumor lobe in the middle cranial fossa. The management and prognosis for the three types of JNA were compared and evaluated. Results Among cases of type I JNA (n = 16), the entire mass was removed by the initial operation in 15 cases and by a repeat operation in 1 case. Among cases of type II JNA (n = 29), the entire mass was removed by the first operation in 24 cases and by repeat operation in 5 cases. In cases of type III JNA (n = 6), the huge calabash-like lobe in the middle cranial fossa could not be completely excised; 4 cases underwent radiotherapy and 2 cases were lost to follow-up. Conclusions 1) The transnasal cavity approach with endoscopic guidance is suitable for type I JNA resection. 2) The transantral–infratemporal fossa–nasal cavity combined approach is reliable for resection of a type II JNA, which extends into the deep anterior cranial fossa and/or minimally into the middle cranial fossa, with intact dura mater. 3) The complete removal of a type III JNA is difficult, even through a combined extracranial and intracranial approach. Radiotherapy is useful for treating the residual intracranial tumor. The successful or failed experiences of 6 typical cases prove that this revised classification system is reasonable and reliable.

The real time acquisition of the optical radiation information of multi points in free space is a difficult problem for the optical fluid fields testing. Traditional data acquisition systems are based on multichannel charge coupled device (CCD), with which the optical radiation information from multi directions can be obtained. However these systems are hard to fit the requirement of parallel beam imaging, and hence bring great errors of inverse computations. A multichannel real time data acquisition system based on a digital signal processor (DSP) and a number of optical fiber bundles (OFBs) is proposed in this paper for fluid field reconstructions. Each OFB unit can acquire the optical radiation information that transmits into its entrance aperture via a sensor unit consisting of an optical fiber coupler and a phototransistor. The DSP acts as a main controller that switches on the exposure of all phototransistors synchronously based on the mechanism of electronic shutter. The synchronous sensed signals are locked by a peak hold circuit and then outputted to analog-to-digital converters (ADCs), and therefore the real time acquisition of the optical radiation information of multi points in free space can be realized, which offers the original parallel beam imaging data for the fluid field reconstructions.

The paper designs a parallel filter based on wavelets theory, a design algorithm of parallel wavelet filter is given and proved. The filter is composed of sampler, prefilter, analyser, frequency subsection processor and synthesizer, the principle of the filter is discussed in detail. The design can be applied in the field which need time-frequency localization.

Combining with the Volterra series model, this paper proposes a novel performance improvement method of nonlinear sensor. Volterra series model, which is considered as a nonlinear filter that can reduce the noise of sensor, presents an effective way for modeling and compensation of nonlinear sensor. The simulation in this paper shows that this scheme can improve the sensor performance effectually. Moreover, the scheme provides nonlinear sensor greater accuracy and environmental suitability.

To evaluate the treatment of advanced squamous cell carcinoma of the tonsil.Eight patients with advanced tonsillar carcinoma underwent resections combining mandibular ramus and oral cavity approaches, neck dissection and one-stage repair of the defect with pectoralis major myocutaneous flap (PM). The managements were supplemented with preoperative chemotherapy and postoperative radiotherapy.Following up 3 to 9 years, 6 of 8 cases(75%) survived for more than 3 years. Two of 8 cases (25%) died of different causes postoperatively. One case died of serious hemorrhage resulted from radio-mandibulomyelitis 3 months after operation, and the other case died of esophageal carcinoma 2 years after operation. Two cases complicated radio-mandibulomyelitis. Two cases suffered from temporary regurgitation of food to the nasal chamber.Through this combined approach, the advanced tonsillar carcinoma could be resected en bloc under direct visual field and keeping 1-1.5 cm safe margin to the tumor. Neck dissection, preoperative chemotherapy and postoperative radiotherapy were supplemental measures. Combined therapy was of great significance in reducing recurrence of the tumor. PM was usually survived and easily obtained, hence, suitable for repairing the pharyngeal defect.

In the case of optical computed tomography (OpCT) reconstructions for the field comprising obstacle objects, parts of the projection data are lost; hence, the image reconstruction would be always imprecise with conventional OpCT algorithms if no other preprocessing or interpolation approaches are adopted. To solve the problem of the reconstruction with incomplete data, a Lagrange interpolation reprojection-revising (LIRR) algorithm is proposed. First a Lagrange interpolation polynomial is adopted to preestimate the lost projection data. By comparing to the reprojection of the rough reconstructed image in the iteration, the unbiased Lagrange interpolation estimations are retained; otherwise, the biased estimations are revised, ray by ray, with the weighed superposition of the interpolation and the reprojection data. These steps are repeated until all estimations for lost data are acceptable. Reconstruction results of some known algorithms and the LIRR algorithm for two typical tested images, including a circle round opaque object, were compared. Additionally, an emission spectral tomography experiment was also designed to evaluate the LIRR. The simulation and experiment results show the LIRR makes a great improvement in reconstruction precision over the traditional OpCT algorithms and hence has potential application of OpCT reconstructions with incomplete data.