3D MERGE与3D SPACE STIR序列在腰椎间盘突出症检查中的应用比较

目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,所有患者均接受常规MRI扫描及3D MERGE、3D SPACE STIR序列扫描,对比3D MERGE、3D SPACE STIR序列测量神经根直径的一致性,评价两种序列的图像质量参数[信噪比(SNR)、对比噪声比(CNR)]、图像清晰度评分。结果:3D MERGE和3D SPACE STIR序列测量的L3~S1神经根直径比较差异无统计学意义(P>0.05),且两组序列测量的L3、L4、L5和S1直径均显示出较高相关性(r=0.957,0.986,0.975,0.972,P<0.05);3D MERGE序列的SNR及CNR均高于3D SPACE STIR序列,神经根显示分级、图像清晰度评分优于3D SPACE STIR序列,差异有统计学意义(P<0.05)。结论:3D MERGE、3D SPACE STIR序列在LDH神经根直径测量中具有极高一致性,3D MERGE序列较3D SPACE STIR序列能够更清晰显示神经跟的解剖形态,图像质量更好。

中医药多元证据整合方法学MERGE框架

在循证医学时代下,依托规范的技术方法和标准化的操作规程发掘中医药独特优势,是实现中医药现代化、国际化发展并惠泽人类的必由之路。中医理论、人用经验和研究证据三结合证据体系的提出标志着中医药特色评价体系思维方法取得了重要进步,经过恰当方法整合后的多元证据体是中医药临床指南推荐意见和循证卫生决策的有力支撑。本文基于当前国际证据合成与分级方法学前沿进展,初步提出中医药多元证据整合的方法学框架——MERGE(Merge Evidence-based Research and artificial intelliGence to support smart dEcision)框架,以期为中医药循证医学方法学体系的完善和发展提供借鉴和参考。

Validation of the multi-satellite merged sea surface salinity in the South China Sea

Sea surface salinity(SSS)is an essential variable of ocean dynamics and climate research.The Soil Moisture and Ocean Salinity(SMOS),Aquarius,and Soil Moisture Active Passive(SMAP)satellite missions all provide SSS measurements.The European Space Agency(ESA)Climate Change Initiative Sea Surface Salinity(CCI-SSS)project merged these three satellite SSS data to produce CCI L4SSS products.We validated the accuracy of the four satellite products(CCI,SMOS,Aquarius,and SMAP)using in-situ gridded data and Argo floats in the South China Sea(SCS).Compared with in-situ gridded data,it shows that the CCI achieved the best performance(RMSD:0.365)on monthly time scales.The RMSD of SMOS,Aquarius,and SMAP(SMOS:0.389;Aquarius:0.409;SMAP:0.391)are close,and the SMOS takes a slight advantage in contrast with Aquarius and SMAP.Large discrepancies can be found near the coastline and in the shelf seas.Meanwhile,CCI with lower RMSD(0.295)perform better than single satellite data(SMOS:0.517;SMAP:0.297)on weekly time scales compared with Argo floats.Overall,the merged CCI have the smallest RMSD among the four satellite products in the SCS on both weekly time scales and monthly time scales,which illustrates the improved accuracy of merged CCI compared with the individual satellite data.

Novel layout design of 4H-SiC merged PiN Schottky diodes leading to improved surge robustness

A method to improve the surge current capability of silicon carbide(SiC)merged PiN Schottky(MPS)diodes is presented and investigated via three-dimensional electro-thermal simulations.When compared with a conventional MPS diode,the proposed structure has a more uniform current distribution during bipolar conduction due to the help of the continuous P+surface,which can avoid the formation of local hotspots during the surge process.The Silvaco simulation results show that the proposed structure has a 20.29%higher surge capability and a 15.06%higher surge energy compared with a conventional MPS diode.The bipolar on-state voltage of the proposed structure is 4.69 V,which is 56.29%lower than that of a conventional MPS diode,enabling the device to enter the bipolar mode earlier during the surge process.Furthermore,the proposed structure can suppress the occurrence of‘snapback'phenomena when switching from the unipolar to the bipolar operation mode.In addition,an analysis of the surge process of MPS diodes is carried out in detail.

xStripeMerge:基于纠删码存储的高效宽条带生成方法

为了解决纠删码存储系统的已有宽条带生成方法中扩容方案将产生大量宽条带生成带宽,合并方案受限于双条带的问题,提出了一种针对多条带合并下的宽条带生成问题的高效宽条带生成方法。定义了多条带合并过程的2个关键算子,并将宽条带生成问题建模为组合优化问题,提出了优先寻找具有小的奇偶校验块传输成本的窄条带组合方案的高效宽条带生成方法xStripeMerge。实验结果表明,与目前最优的存储扩容方法相比,xStripeMerge可以减少75%宽条带生成带宽。xStripeMerge的时间和空间复杂度远优于扩展的双条带合并方法,xStripeMerge可以在更短的时间内获得与其性能相近的宽条带生成方案,并且xStripeMerge可以适用于大规模存储系统。

A wave energy resource assessment in the China's seas based on multi-satellite merged radar altimeter data

Wave energy resources are abundant in both offshore and nearshore areas of the China＇s seas. A reliable assessment of the wave energy resources must be performed before they can be exploited. First, for a water depth in offshore waters of China, a parameterized wave power density model that considers the effects of the water depth is introduced to improve the calculating accuracy of the wave power density. Second, wave heights and wind speeds on the surface of the China＇s seas are retrieved from an AVISO multi-satellite altim-eter data set for the period from 2009 to 2013. Three mean wave period inversion models are developed and used to calculate the wave energy period. Third, a practical application value for developing the wave energy is analyzed based on buoy data. Finally, the wave power density is then calculated using the wave field data. Using the distribution of wave power density, the energy level frequency, the time variability indexes, the to-tal wave energy and the distribution of total wave energy density according to a wave state, the offshore wave energy in the China＇s seas is assessed. The results show that the areas of abundant and stable wave energy are primarily located in the north-central part of the South China Sea, the Luzon Strait, southeast of Taiwan in the China＇s seas; the wave power density values in these areas are approximately 14.0–18.5 kW/m. The wave energy in the China’s seas presents obvious seasonal variations and optimal seasons for a wave energy utilization are in winter and autumn. Except for very coastal waters, in other sea areas in the China＇s seas, the energy is primarily from the wave state with 0.5 m≤Hs≤4 m, 4 s≤Te≤10 s whereHs is a significant wave height andTe is an energy period; within this wave state, the wave energy accounts for 80% above of the total wave energy. This characteristic is advantageous to designing wave energy convertors （WECs）. The practical application value of the wave energy is higher which can be as an effective supplement for an energy con-sumption in some areas. The above results are consistent with the wave model which indicates fully that this new microwave remote sensing method altimeter is effective and feasible for the wave energy assessment.

A new merged dataset of global ocean chlorophyll a concentration with higher spatial and temporal coverage

Understanding the ocean＇s role in the global carbon cycle and its response to environmental change requires a high spatio-temporal resolution of observation.Merging ocean color data from multiple sources is an effective way to alleviate the limitation of individual ocean color sensors（e.g.,swath width and gaps,cloudy or rainy weather,and sun glint） and to improve the temporal and spatial coverage.Since the missions of Sea-Viewing Wide Field-of-View Sensor（Sea Wi FS） and Medium-spectral Resolution Imaging Spectrometer（MERIS） ended on December 11,2010 and May 9,2012,respectively,the number of available ocean color sensors has declined,reducing the benefits of the merged ocean color data with respect to the spatial and temporal coverage.In present work,Medium Resolution Spectral Imager（MERSI）/FY-3 of China is added in merged processing and a new dataset of global ocean chlorophyll a（Chl a） concentration（2000–2015） is generated from the remote sensing reflectance（Rrs（λ）） observations of MERIS,Moderate-resolution imaging spectra-radiometer（MODIS）-AQUA,Visible infrared Imaging Radiometer（VIIRS） and MERSI.These data resources are first merged into unified remote sensing reflectance data,and then Chl a concentration data are inversed using the combined Chl a algorithm of color index-based algorithm（CIA） and OC3.The merged data products show major improvements in spatial and temporal coverage from the addition of MERSI.The average daily coverage of merged products is approximately 24% of the global ocean and increases by approximately 9% when MERSI data are added in the merging process.Sampling frequency（temporal coverage） is greatly improved by combining MERSI data,with the median sampling frequency increasing from 15.6%（57 d/a） to 29.9%（109 d/a）.The merged Chl a products herein were validated by in situ measurements and comparing them with the merged products using the same approach except for omitting MERSI and Glob Colour and MEa SUREs merged data.Correlation and relative error between the new merged Chl a products and in situ observation are stable relative to the results of the merged products without the addition of MERSI.Time series of the Chl a concentration anomalies are similar to the merged products without adding MERSI and single sensors.The new merged products agree within approximately 10% of the merged Chl a product from Glob Colour and MEa SUREs.

Simulation study of a mixed terminal structure for 4H-SiC merged PiN/Schottky diode

In this paper, a mixed terminal structure for the 4H-SiC merged PiN/Schottky diode （MPS） is investigated, which is a combination of a field plate, a junction termination extension and floating limiting rings. Optimization is performed on the terminal structure by using the ISE-TCAD. Further analysis shows that this structure can greatly reduce the sensitivity of the breakdown voltage to the doping concentration and can effectively suppress the effect of the interface charge compared with the structure of the junction termination extension. At the same time, the 4H-SiC MPS with this termination structure can reach a high and stable breakdown voltage.

A 4H-SiC merged P–I–N Schottky with floating back-to-back diode

A novel 4 H-Si C merged P–I–N Schottky(MPS)with floating back-to-back diode(FBD),named FBD-MPS,is proposed and investigated by the Sentaurus technology computer-aided design(TCAD)and analytical model.The FBD features a trench oxide and floating P-shield,which is inserted between the P+/N-(PN)junction and Schottky junction to eliminate the shorted anode effect.The FBD is formed by the N-drift/P-shield/N-drift and it separates the PN and Schottky active region independently.The FBD reduces not only the Vturn to suppress the snapback effect but also the Von at bipolar operation.The results show that the snapback can be completely eliminated,and the maximum electric field(Emax)is shifted from the Schottky junction to the FBD in the breakdown state.

基于VVC的多方向细化Merge模式优化算法

针对多功能视频编码标准VVC帧间预测中,Merge模式未充分考虑运动存在的多种方向性从而降低了预测精度的问题,提出了一种基于VVC的多方向细化Merge模式优化算法。本算法在分析带运动矢量差的Merge技术的基础上,首先调整了步长选择范围并增加多种搜索方向,然后根据步长自适应选择色度块的运动补偿方式,并最终根据率失真代价准则选择最优的运动矢量信息。实验结果表明,本文算法与VTM-12.0参考模型相比,在低延迟P帧配置下Y、U、V三分量的BD-rate分别平均下降了0.57%、0.62%、0.25%,在随机接入配置下的BD-rate中Y分量下降了0.27%、U分量仅提高了0.11%、V分量降低了0.04%,有效地提升了Merge模式的编码性能。

Simulation research on offset field-plate used as edge termination in 4H-SiC merged PiN-Schottky diodes

A new structure of 4H-silicon carbide （SIC） merged PiN-Schottky （MPS） diodes with offset field-plate （FP） as edge termination is developed. To understand the influences of 4H-SiC MPS diodes with offset FP on the characteristics, simulations have been done by using ISE TCAD. Related factors of offset FP have been studied as well to optimise the reverse characteristics of 4H SiC MPS diodes. The simulation results show that the device using offset FP can create a higher blocking voltage under reverse bias as compared with that using field guard rings. Besides, the offset FP does not cause any extra steps in the manufacture of MPS diodes.

Analytical model for reverse characteristics of 4H-SiC merged PN Schottky (MPS) diodes

A new analytical model for reverse characteristics of 4H-SiC merged PN Sehottky diodes （MPS or 3BS） is developed. To accurately calculate the reverse characteristics of the 4H SiC MPS diode, the relationship between the electric field at the Schottky contact and the reverse bias is analytically established by solving the cylindrical Poisson equation after the channel has pinched off. The reverse current density calculated from the Wentzel-Kramers-Brillouin （WKB） theory is verified by comparing it with the experimental result, showing that they are in good agreement with each other. Moreover, the effects of P-region spacing （S） and P-junction depth （Xj） on the characteristics of 4H-SiC MPS are analysed, and are particularly useful for optimizing the design of the high voltage MPS diodes.

TWIDDLE FACTOR MERGED TIME-DECIMAL FFT ALGORITHM AND THE SOFTWARE IMPLEMENTATION FOR TWIDDLE FACTOR MERGED FFT ALGORITHM

Martens proposed a highly efficient and simply formed DFT algorithm——RCFA,whose efficien-cy is comparable with that of WFTA or that of PFA,and whose structure is similar to that of FFT.Theauthors have proved that,in the case of radix 2,the RCFA is exactly equivalent to the twiddle factor mergedfrequency-decimal FFT algorithm.The twiddle factor merged time-decimal FFT algorithm is providedin this paper.Thus,in any case,the FFT algorithm used currently can be replaced by the more efficientalgorithm——the twiddle factor merged FFT algorithm,with exactly the same external property and thesimilar internal structure.Also in this paper,the software for implementing the twiddle factor merged FFTalgorithm(TMFFT)is provided.

Influence of geometrical parameters on the behaviour of SiC merged PiN Schottky rectifiers with junction termination extension

This paper investigates the behaviours of 4H--SiC merged PiN Schottky （MPS） rectifiers with junction termination extension （JTE） by extensive numerical simulations. The simulated results show that the present model matches the experimental data very well. The influences of the JTE design parameters such as the doping concentration and length of the JTE on the breakdown characteristics are discussed in detail. Then the temperature sensitivity of the forward behaviour is studied in terms of the different designs of 4H--SiC MPS with JTE, which provides a particularly useful guideline for the optimal design of MPS rectifiers with JTE.

Construction of Domain Web Classification Ontology Based on Suggested Upper Merged Ontology

Aiming at the problem of merging heterogeneous semantic taxonomy emerged in Web information integration, a method of building Web classification ontology （WCO） has been proposed. A WCO that is logically consistent with the suggested upper merged ontology （SUMO） is defined, together with axioms needed to classify Web pages. WCO can be used as a foundation of merging heterogeneous semantic taxonomy, and could be used to support Web information integration and classification based Web information retrieval.

Analysis of the merged quasi-geoid of neighbouring areas

Employing the merged quasi-geoid, we analyses the causes of systematic errors in modelling of quasigeoid of neighbouring areas in the paper, and the efficient method is introduced to improve the accuracy of quasi-geoid. First, the systematic error is weakened with the moving window method applied to established quasi-geoids in two adjacent regions, and the accuracy of the merged quasi-geoid in the stitching region is checked using the measured GPS benchmark data; Second, the whole quasi-geoid is recomputed with data obtained from two adjacent regions if the accuracy of the quasi-geoid obtained from the first step in the stitching region is low; Finally, the quasi-geoids in two adjacent regions are recomputed respectively using GPS benchmark data of own region and adjacent region with the same solution if the accuracy of whole quasi-geoid obtained from the second step also is low. Actual data sets from Sichuan Province and Chongqing City are employed to test the moving window method. It is shown that the quasi-geoid models with high resolution and accuracy were obtained.

Merged of Three IT Companies,Results,and Recommendations

The purpose of this paper is to evaluate the result of merge three companies.The researcher has examined the merge case through the collected information from three senior managers.The financial losses and mismanagement(after the merge)are the critical problems of the merge.The best solution is proper planning.A business plan can help companies to achieve their priorities.The operations deliver high performance by managerial processes that performance in the long-term.Moreover,the company shall care of employees through defining companies’capabilities.The professional management will have a direct positive effect on the company’s performance while unprofessional management will have a negative impact on company performance—also,the unprofessional merge negative effect in leading the company to success.

Carto-Merge技术在左肺静脉共干伴阵发性房颤患者导管消融术中的应用

目的探讨Carto-Merge技术指导存在左肺静脉共干的阵发性房颤患者行导管消融术的临床效果。方法选择存在左肺静脉共干的阵发性房颤患者27例,随机分为A组13例与B组14例。B组在Carto3技术建立的电解剖标测(FAM)模型指导下进行双侧肺静脉导管消融术,A组在Carto-Merge技术建立的影像融合模型(术前CT三维图像融合Carto3系统指引下建立的FAM模型)指导下进行双侧肺静脉导管消融术。记录并比较A组FAM模型与CT三维图像、B组FAM模型的左肺静脉相关参数(上下径、前后径、开口面积)及左心房容积,比较两组消融环相关参数(消融环上下径、前后径、横截面积、上下径比值、前后径比值及消融环横截面积/左肺静脉开口面积)。两组术后随访6个月,记录消融结局相关指标(双侧肺静脉电隔离完成情况、左右肺静脉消融时间及肺动脉压增高、窦性心律维持情况)。结果A组CT三维图像的左肺静脉开口面积、左心房容积均小于FAM模型(P均<0.05),两组FAM模型的左肺静脉上下径、前后径、开口面积及左心房容积比较差异均无统计学意义(P均>0.05)。A组消融环前后径、横截面积、前后径比值、消融环横截面积/左肺静脉开口面积均大于B组(P均<0.05)。两组消融环上下径、上下径比值及左、右肺静脉消融时间比较差异均无统计学意义(P均>0.05)。两组均顺利完成双侧肺静脉电隔离,其肺动脉压增高率、窦性心律维持率比较差异均无统计学意义(P均>0.05)。结论采用Carto-Merge技术指导存在左肺静脉共干的阵发性房颤患者进行导管消融术时不会增加手术时间,其消融效果与传统Carto3技术相当且安全性较高,有助于复杂肺静脉解剖结构的识别和消融。

Two CAS Institutes in Xinjiang Merged

Apreludial step of the current drive for structural adjustment in the CAS system, the establishment of Xinjiang Institute of Ecology & Geography was announced on July 7, 1998. The new institute is to incorporate the research resources of two former CAS institutes in the region in a bid to concentrate scattered R&D expertise and promote the interdependence of different disciplines in the implementation of national program