Surgical treatment of severe anterior capsular organized hard core cataract: A case report

BACKGROUND Complicated cataract surgery is challenging,especially in cases of hard nuclear cataract with severe anterior capsule organization.It is important to avoid the risk of surgery and improve the surgical skills of surgeons.CASE SUMMARY A 60-year-old man presented with severe cataract and visual impairment.The anterior capsule of the lens was irregularly organized and pulled to the surrounding capsule,and white porcelain organized cord and brown-black lens nucleus were clearly visible.In phacoemulsification,maintaining the anterior capsule round and intact plays a key role in a successful surgery.In this case,if the conventional capsule treatment method was used,the anterior capsule would be torn.Therefore,we adopted a segmented anterior capsule treatment method,and a blasting method to release energy when dealing with the lens nucleus,and achieved good surgical results.CONCLUSION Complicated cataract surgery is challenging and requires precise skills.Operation plans should be made reasonably to predict the risk of surgery,and improve the visual quality of the patients.

Design and Performance Analysis of Permanent Magnet Claw Pole Machine with Hybrid Cores

Permanent magnet claw pole machine(PMCPM) is a special kind of transverse flux permanent magnet machine. Compared with other electrical machines, it has the advantages of high torque density and high efficiency for high speed operation. However, because of its complex irregular structure, the manufacturing process using silicon sheets is complicated. Soft magnetic composite material(SMC) is manufactured by powder metallurgy technology, which can produce various shapes of stator core structures, so it is easier to produce various irregular shapes of the stator core. However, the raw SMC material is relatively expensive, and the mechanical strength of SMC is weak. In this paper, a PMCPM with hybrid cores is proposed. With the adoption of hybrid silicon sheet-SMC cores and amorphous alloy-SMC cores, the torque ability of PMCPM can be improved greatly and it can have higher efficiency for more wide operation frequency. Meanwhile, its mechanical strength has been improved and it can be designed for high torque direct drive applications as it is a modular machine. Furthermore, three methods are proposed to reduce the additional eddy current loss which resulted from the employment of hybrid cores in PMCPM.

FRACTAL STRUCTURE OF THE CORE LOSS SPECTURM OF Fe-B-Si AMORPHOUS SOFT MAGNETIC ALLOY

The core loss spectrum P(f) of Fe-B-Si amorphous soft magnetic alloy has been studied.It is found that P(f) has the fractal structure.The effect of heat treatment on the fractal dimension Df is discussed.

Behavior of Medium-frequency Core Loss in Fe-based Nanocrystalline Soft Magnetic Alloys

The dependences of the power loss per cycle on frequency have been investigated in the ranges of 100 Hz<= f<=25000 Hz and 0.1 T< =Bm <=1.0 T for three main original magnetic states in five sorts of Fe-based nanocrystalline soft magnetic alloys. The measured and calculated results showed that the total power loss per cycle clearly exhibited a nonlinear behavior in the range below 3 kHz～5 kHz depending on both the magnetic state and the value of Dm, whereas it showed a quasi-linear behavior above this range. The total loss was decomposed into hysteresis loss, classical eddy current loss and excess loss, the obvious nonlinear behavior has been confirmed to be completely determined by the dependence of the excess loss on frequency. It has been indicated that the change rate of the excess loss per cycle with respect to frequency sharp decreases with increasing frequency in the range below about 3 kHz～5 kHz, wherease the rate of change slowly varies above this range, thus leading to the quasilinear behavior of the total loss per cycle. In this paper, some linear expressions of the total loss per cycle has been given in a wider medium-frequency segment, which can be used for roughly estimating the total loss.

A k-Coverage Scheduling Scheme in Wireless Sensor Network Based on Hard-Core Process in Rayleigh Fading Channel

Sensing coverage is a fundamental design issue in wireless sensor networks(WSNs),while sensor scheduling ensures coverage degree to the monitored event and extends the network lifetime.In this paper,we address k-coverage scheduling problem in dense WSNs,we maintain a connected k-coverage energy efficiently through a novel Hard-Core based Coordinated Scheduling(HCCS),in which hardcore is a thinning process in stochastic geometry that inhibits more than one active sensor covering any area redundantly in a minimum distance. As compared with existing coordinated scheduling,HCCS allows coordination between sensors with little communication overhead.Moreover,due to the traditional sensing models in k-coverage analysis is unsuitable to describe the characteristic of transmit channel in dense WSNs,we propose a novel sensing model integrating Rayleigh Fading and Distribution of Active sensors(RFDA),and derive the coverage measure and k-coverage probability for the monitored event under RFDA. In addition,we analyze the influence factors,i.e. the transmit condition and monitoring degree to the k-coverage probability. Finally,through Monte Carlo simulations,it is shown that the k-coverage probability of HCCS outperforms that of its random scheduling counterpart.

The 3D Simulation of Liquid Core Change of Cylinder Steel Rolling Forming on Soft-reduction Continuous Casting Process

Using ABAQUS FEM software,the Elastic-plastic with isotropic hardening model is applied to simulate 3D cylinder slab rolling forming in continuous casting (CC),the change of liquid core before slab solidification completely on soft re- duction process is studied,the analyse result shows the soft reduction technique can change the liquid core size,which is useful to cylinder slab forming in CC.

A Hydraulic Hammer Corer Utilizing Hydrostatic Energy for Hard Seafloor Sediment Coring

The paper presents the design and preliminary test results of a corer used for hard seafloor sediments sampling. Generally the sediment cores are provided by either gravity-type coting or deep-ocean drilling for a range of studies. However, in consideration of the operability and available sample length in collecting hard sediments, these methods exhibit no advantages. In this paper, a new corer which can exploit both hydrostatic energy and gravity energy for hard sediments coting is presented. The hydrostatic energy is provided by pressure differential between ambient seawater pressure and air pressure in an empty cavity. During sampling process, the corer penetrates into the sediment like a gravity corer and then automatically shifts to the percussion mode. The experiments in the laboratory indicate that the corer can complete 40 cycles in the sea with a cycle time of 2.8 seconds in percussion mode and impact the sample tube with the velocity of 0.2 m/s during each cycle. Besides, its adjustable falling velocity can make the corer achieve the maximum efficiency in coring different sediments.

Fractal Structure of the Core Loss Spectrum of Co-based Amorphous Soft Magnetic Alloy with Constant Permeability

In order to check the traditional core loss formula, the core loss spectrum P(f) of Co-based amorphous soft magnetic alloy with constant permeability has been studied. It is found that within a high frequency range from 10 kHz to 200 kHz and at Bm = 0. 1 T,the P(f) has the fractal structure P (f) = Po, and with the increasing of induced anisotropy energy Ku, the fractal dimension Dfrises, thus the total power loss at high frequency increases and the frequency characteristic of P(f) becomes worse.

Soft Information,Core Competitive Edge and Private Relationship Lending——A Case of Village Banks

In view of the development problems of village banks,through introducing the concept of private relationship lending,the functions of soft information,the channels of village banks for collecting soft information,and the private relationship lending of village banks under Chinese rural human environment of highlighting relationship while despising rationality are proved.According to the recognition standard of core competitive edge,it can be concluded that the core competitive edge of village banks is private relationship lending.In the first place,these kinds of small and medium-sized quarter banks have competitive advantages in launching private relationship lending;in the second place,the lending businesses of village banks based on soft information attracts small and medium clients;in the third place,the private relationship lending has realized the scale economy.Furthermore,the reasons why village banks can not display the core competitive edge have been analyzed:firstly,village banks have not found that private relationship lending is their core competitive edge;secondly,the internal motivation on establishing private relationship lending of village banks is insufficient;thirdly,village banks have not prepared well in developing private relationship lending;The relevant policies and countermeasures are put forward,including transforming idea and vigorously developing private relationship lending;intensifying training and improving the quality of personnel involved;strengthening supervision and avoiding the violation behaviors of personnel involved;emulating experiences and perfecting the private relationship lending mechanism of village banks.

Hard IP Core Nondestructive Testing Technology

Based on the analysis of the existing hard IP core testing technology, the hard IP core nondestructive testing technology was studied, according to the verification requirements of a large number of hard IP core precise and fast testing. Combined with the external automatic test equipment (ATE) and the on-chip evaluation circuit, a general evaluation system of simulating user system on chip (SOC) with signal timing calibration and compensation by software and hardware compensation structures were introduced to realize the function, performance and reliability verification of the hard IP core. The design and verification of a random access memory (SRAM) hard IP core based on an on-chip evaluation circuit was actually completed, and the key timing parameters of the hard IP core were tested. The address setup time parameter was taken as an example to analyze the specific testing method and the test results were obtained. With this testing technology, the accuracy of testing the timing parameters of hard IP core can reach pS level, compared with the hard IP core packaged test, the accuracy of the result data is fully reflected.

Techniques and Apparatus for Measuring Rotational Core Losses of Soft Magnetic Materials

In many situations such as the cores of a rotating electrical machine and the T joints of a multiphase transformer, the local flux density varies with time in terms of both magnitude and direction, i.e. the flux density vector is rotating. Therefore, the magnetic properties of the core materials under the rotating flux density vector excitation should be properly measured, modeled and applied in the design and analysis of these electromagnetic devices. This paper presents an extensive review on the development of techniques and apparatus for measuring the rotational core losses of soft magnetic materials based on the experiences of various researchers in the last hundred years.

The Communist Party of China Has Always Been the Firm Core of Leadership for China's Human Rights Development and Progress

Under the leadership of the Communist Party of China,the human rights cause in China has developed and progressed through the period of democratic revolution,the early founding of the People’s Republic of China,the new period of reform and openingup,and the new era of socialism with Chinese characteristics.all previous national Congresses of the Communist Party of China have made illustrations and arrangements on human rights issues,and the successive Party leaders have made important expositions on human rights issues.The Party and the state have enacted a series of policies,laws,and regulations to protect human rights in various periods.China has made historic and great achievements in human rights practice and created a human rights development path suited to China’s national conditions.China’s human rights development over the past century has fully proved that the CPC has always been,and it remains,the firm core of leadership for China’s human rights development and progress.

基于IP Core的PXI Express接口DMA引擎设计

PXI Express是PCI Express在仪器领域的扩展。采用Xilinx公司的PCI Express端点硬核,详细阐述了一种通用DMA引擎的实现方法,对DMA读写操作流程和设计思想进行了详细的分析和说明,并提出了提高DMA引擎数据传输速率的优化方法。分别在硬件层和软件层进行测试,设计的DMA引擎可以达到较高的数据传输速率,为PXI Express接口提供了一种通用的解决方案,可以满足PXI Express系统中对高数据带宽的传输需求,具有很好的应用价值。

Analysis and Application of the Series Core Snubber

The transformer core snubber （CS）, as one of the most important components in the EAST （experimental advanced superconducting tokamak） NBI （neutral beam injector） system, is designed to limit grid damage and protect the ion source during periods of electrical breakdowns. A transformer core snubber is analyzed in detail in this paper. Several kinds of soft magnetic cores are presented and compared. With analysis and experiment on the basic characteristics of the cores, the most suitable materials are suggested. The circuit simulation code is established which could simulate faulty conditions with concentrated and distributed CS concepts. Based on the above work, an ion source CS is developed with series type of distributed topology. The CS has been subjected to experimental validation at 80 kV with a peak short-current of approximately 400 A in a real NBI system, which proves the accuracy of the adopted assumptions and the analysis method.

High-frequency magnetic properties and core loss of carbonyl iron composites with easy plane-like structures

To fully release the potential of wide bandgap(WBG)semiconductors and achieve high energy density and efficiency,a carbonyl iron soft magnetic composite(SMC)with an easy plane-like structure is prepared.Due to this structure,the permeability of the composite increases by 3 times(from 7.5 to 21.5)at 100 MHz compared with to the spherical carbonyl iron SMC,and the permeability changes little at frequencies below 100 MHz.In addition,the natural resonance frequency of the composite shifts to higher frequencies at 1.7 GHz.The total core losses of the composites at 10,20,and 30 m T are80.0,355.3,and 810.7 m W/cm^(3),respectively,at 500 k Hz.Compared with the spherical carbonyl iron SMC,the core loss at500 k Hz is reduced by more than 60%.Therefore,this kind of soft magnetic composite with an easy plane-like structure is a good candidate for unlocking the potential of WBG semiconductors and developing the next-generation power electronics.

Electromagnetic Performance Analysis of Flux-Switching Permanent Magnet Tubular Machine with Hybrid Cores

The performance of traditional flux switching permanent magnet tubular machine(FSPMTM)are improved by using new material and structure in this paper.The existing silicon steel sheet making for all mover cores or part of stator cores are replaced by soft magnetic composite(SMC)cores,and the lamination direction of the silicon steel sheet in stator cores have be changed.The eddy current loss of the machine with hybrid cores will be reduced greatly as the magnetic flux will not pass through the silicon steel sheet vertically.In order to reduce the influence of end effect,the unequal stator width design method is proposed.With the new design,the symmetry of the permanent magnet flux linkage has been improved greatly and the cogging force caused by the end effect has been reduced.Both 2-D and 3-D finite element methods(FEM)are applied for the quantitative analysis.

功能迭代中的国际科技创新中心:演进路径与风险应对

在全球化经济和社会面临严峻转型挑战的背景下,建设国际科技创新中心已经成为各国推动科技进步、加速产业升级和促进可持续发展的关键战略。在阐述国际科技创新中心的内涵特征、诞生背景与空间转移过程的基础上,从发展驱动力、创新机构来源与主导产业类型这三个维度,分析总结不同时代背景下代表性的国际科技创新中心的发展模式,可构建处于迭代中的五大核心组织功能:基础科研、集成创新、产业驱动、辐射引领与制度试验。在此基础上,归纳其在组织形式、组织载体、驱动力量、关联模式、引才策略方面具有典型意义的演进路径,提出功能迭代中的国际科技创新中心发展需积极识别并化解应对在硬科技、创新成本、创新资源,及其全球科研竞争与协作方面潜在的风险挑战。

国有企业推进关键核心技术突破对协同创新网络竞合关系的治理机制——基于“华龙一号”核电技术案例研究

国有企业是科技创新的主力军,在“卡脖子”关键核心技术突破中如何对创新网络多主体竞合关系进行有效治理是推进科技创新的关键。选取中核工程作为案例研究对象,基于竞合关系与利益相关者视角探究国有企业作为核心企业对创新网络竞合关系的治理机制。研究发现:①国有企业对协同创新网络主体存在行政要素驱动、技术要素驱动和利益要素驱动3类竞合关系;②针对不同类型竞合关系,分别采取行政协调、柔性治理与规范合作3种细分机制,促进创新网络主体良性合作,同时对价值创造与分配中存在的竞合关系进行有效治理。研究结论有助于丰富国有企业情境下的关键核心技术突破研究,为国有企业管理协同创新网络主体提供参考。

伽马能谱测井在罗辛铀矿勘查中的应用研究

纳米比亚罗辛铀矿床属于白岗岩铀-钍混合型矿床。在一定量矿心分析数据对比基础上,一直沿用γ测井解释结果作为铀资源储量估算的基础数据。针对该伽马测井结果,要经过各种校正,尤其是钍作为一种“干扰”的不可忽视的因素。大量(岩)矿心分析历史数据表明,罗辛铀矿床Th/U比随着矿体走向、倾向以及深度、蚀变、岩性的变化而变化;通过数理统计分析矿心Th/U比采用常数法或者函数拟合方法用于γ测井的钍修正。但利用伽马能谱测井方法可直接获取矿(化)段的铀、钍元素含量。从仪器、数据采集、误差分析、伽马能谱测井解释铀含量与钍修正后γ测井解释铀含量,以及与矿心分析元素含量对比等几方面进行论述,验证该方法的可靠性和可信度。结果表明,伽马能谱测井是一种快速、有效的测井方法,尤其适用于热液型铀矿勘查。

深井高速涡轮钻配套同径取心技术研究

分析了涡轮钻具结构特征及性能特点,在深井、特深井的高温高压、强研磨性地层中,涡轮钻具基本上成为唯一可选的用于复合钻进提速降本的井下动力钻具。针对深部资源的勘探开发需求,阐述了现有涡轮钻具同径取心技术的优势及存在的问题,利用数值模拟仿真技术分析和研究了涡轮钻具同径取心过程中钻井液的流动状态对取心效果的影响,认识到涡轮钻具可耐高温,适于深井、特深井全面钻进及取心钻进,但其高转速在取心钻进过程也容易造成岩心磨损、岩柱螺旋,而改善同径取心钻具高速单动性能、加长涡轮钻具螺旋稳定器、利用反螺旋扰流板等技术措施,有利于减小取心钻具井底的涡动、降低岩心内外管轴向速度差,从而提高涡轮钻同径取心钻进的岩心质量。