A Trove of Masterpieces

The special exhibition“The Greats of Six Centuries:Masterpieces from the Museo Nacional Thyssen-Bornemisza,”held in Shanghai provides profound insight into the evolution of Western culture,lifestyle,and social landscapes over the 600 years.

Experimental Study on Entropy Features in Machining Vibrations of A Thin-Walled Tubular Workpiece

In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and efficiency.Accurate and timely monitoring of chatter is helpful to maintain stable machining operations.At present,most chatter monitoring methods are based on the energy level at specified chatter frequencies or frequency bands.However,the spectral features of chatter could change during machining operations due to complexity and time-varying dynamics of the physical machining process.The purpose of this paper is to investigate the time-varying chatter features in turning of thin-walled tubular workpieces from the perspective of entropy.The airborne acoustics was selected as the source of information for machining condition monitoring.First,corresponding to the distinguishing surface topographies relevant to machining conditions,the features of the sound signal emitted during turning of the thin-walled cylindrical workpieces were extracted using the spectral analysis and wavelet packet transform,respectively.It was shown that the dominant vibration frequency as well as the energy distribution could shift with the transition of the machining status.After that,two relative entropy indicators based on the spectrum and the wavelet packet energy were constructed to identify chattering events in turning of the thin-walled tubes.The experimental results demonstrate that the proposed indicators could accurately reflect the transition of machining conditions with high sensitivity and robustness in comparison with the traditional FFT-based methods.The achievement of this study lays the foundations of the online chatter monitoring and control technique for turning of the thin-walled tubular workpieces.

Study on Problems and Countermeasures in the Management of Spot Check of Chinese Herbal Pieces

Objective To provide suggestions for optimizing the sampling management of Chinese herbal pieces and improving the quality Chinese herbal pieces.Methods Logical reasoning method was used to analyze the problems in the drug spot check of Chinese herbal pieces based on the data of drug quality published by the National Medical Products Administration from 2013 to 2021,combined with the current provisions and implementation of drug spot check management in China.Results and Conclusion At present,there are some problems in the drug spot check of Chinese herbal pieces,such as fewer varieties of Chinese herbal pieces in the national drug spot check,the unreasonable sampling links,the insufficient territorial management in some areas,and error-prone sample extraction.It is suggested that the actual quantity and overall quality of Chinese herbal pieces should be fully considered in the formulation of sampling plan.Besides,the variety coverage of drug spot check of traditional Chinese medicine should be strengthened.In the planning,the sampling links shall be made as a whole,and the credit rating and distribution of drug production,operation and use units within the jurisdiction shall be fully combined.While strengthening the sampling management at the production end in areas with concentrated industries,regional special drug spot check should be carried out or the administrative forces at the provincial,municipal and county levels should be fully mobilized to avoid local protection.In the assigned tasks,the name of Chinese herbal pieces should be accurately expressed to avoid the sampling errors of Chinese herbal pieces with the same original medicinal materials and different processing methods.

基于语料分析的文化负载词英译描述性研究——以Thousand Pieces of Gold为例

母语为英语的华裔作家多以海外华人生活或华人历史为背景进行文学创作,他们的文学创作呈现出一种用英语表达中国社会文化的‘翻译性',是一种涉及到英语母语和目的语汉语两种语言的转换的文学创作。鉴于这种特殊性,本研究以Ruthanne Lum McCunn的英文原版小说Thousand Pleces of Gold(《千金》)作为研究文本,结合语料对作品中汉语文化负载词的英语表达规律进行描述分析来探讨汉语文化负载词的英译策略。

针对BitTorrent协议中Piece消息的隐写分析方法

网络隐写是当前网络攻击中常见的一种隐蔽通信方式,给网络安全造成了极大隐患。BitTorrent网络作为一种使用极为广泛的协议,拥有巨大流量,是隐藏信息的极佳载体。近来,有研究者提出了一种基于Piece消息的网络隐写方法,公开文献中尚无有效的检测算法。针对此,提出一种基于多特征分类的检测方法。提取正常和含密Piece消息数据流;提取网络数据流时间序列的均值、方差与信息熵特征;使用SVM分类器给出检测结果。实验结果显示,在观测窗口为1000个数据包时,该方法对基于Piece消息隐写的检测率可达94.7%。

FPSO船体结构建造Piece Mark进度报表开发与应用

本文针对国外业主对Piece Mark表的提交需求,结合海洋石油工程股份有限公司的PCMS系统,采用VSTO编程技术,对该进度报表进行了研究和开发,并在某国外FPSO船体建造项目中进行了应用。

Identification of Kinematic Errors of Five-axis Machine Tool Trunnion Axis from Finished Test Piece

Compared with the traditional non-cutting measurement,machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users.However,measurement and calculation of the machining tests in the literature are quite difficult and time-consuming.A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed.Firstly,a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics.Then,the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool.By adopting the error-sensitive vectors in the matrix calculation,the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors.According to our previous work,the kinematic errors of C-axis can be treated as the known quantities,and the kinematic errors of A-axis can be obtained from the equations.This method was tested in Mikron UCP600 vertical machining center.The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis.Experimental results demonstrated that the proposed method can reduce the complexity,cost,and the time consumed substantially,and has a wider applicability.This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.

Surface Magnet Gears with a New Magnet Arrangement and Optimal Shape of Stationary Pole Pieces

In mechanical gear systems, dust, noise, vibration, and tooth wear are generated by frictions among gear teeth, and suppressing friction requires lubrication. Magnetic gears transmit torque by magnetic forces without contact and so avoid contact-related problems. The present paper discusses magnet arrangements and the shape of stationary gear teeth to improve transmission torque in surface magnet type magnetic gear transmission mechanisms.

A Dual-Platform Laser Scanner for 3D Reconstruction of Dental Pieces

This paper presents a dual-platform scanner for dental reconstruction based on a three-dimensional(3D)laser-scanning method.The scanner combines translation and rotation platforms to perform a holistic scanning.A hybrid calibration method for laser scanning is proposed to improve convenience and precision.This method includes an integrative method for data collection and a hybrid algorithm for data processing.The integrative method conveniently collects a substantial number of calibrating points with a stepped gauge and a pattern for both the translation and rotation scans.The hybrid algorithm,which consists of a basic model and a compensation network,achieves strong stability with a small degree of errors.The experiments verified the hybrid calibration method and the scanner application for the measurement of dental pieces.Two typical dental pieces were measured,and the experimental results demonstrated the validity of the measurement that was performed using the dual-platform scanner.This method is effective for the 3D reconstruction of dental pieces,as well as that of objects with irregular shapes in engineering fields.

Torsional vibration analysis of lathe spindle system with unbalanced workpiece

For the purpose of analyzing the torsional vibration caused by the gravitational unbalance torque arisen in a spindle system when it is machining heavy work piece,a 10-DOF lumped parameter model was made for the machine tool spindle system with geared transmission.By using the elementary method and Runge-Kutta method in Matlab,the eigenvalue problem was solved and the pure torsional vibration responses were obtained and examined.The results show that the spindle system cannot operate in the desired constant rotating speed as far as the gravitational unbalance torque is engaged,so it may cause bad effect on machining accuracy.And the torsional vibration increases infinitely near the resonant frequencies,so the spindle system cannot operate normally during these spindle speed ranges.

“a piece of+名词”与其修饰语

在“a piece of+名词”结构中,作修饰语的形容词出现在piece 之前与出现在名词之前这两种情况都有。例如: a piece of good luck;a piece of bad news 与 a finepiece of work;a delicate piece of mechanism 等等。还可以举出许多例子。那么,这是否就等于说该结构中的形容词可以任意放在上述两个位置中的一个上呢?也不尽然。笔者查阅了若干词典。

Finite element analysis of multi-piece post-crown restoration using different types of adhesives

The multi-piece post-crown technique is more effective in restoring residual root than other restoration techniques.Various types of adhesives have different material properties that affect restoration.Therefore,the choice of adhesive is particularly important for patients.However,the effect of different kinds of adhesives was not too precise by experimental methods when concerning about individual differences of teeth.One tooth root can only be restored with one type of adhesive in experiment.After the mechanical test,this tooth root cannot be restored with other adhesives.With the help of medical imaging technology,reverse engineering and finite element analysis,a molar model can be reconstructed precisely and restored using different types of adhesives.The same occlusal and chewing loads were exerted on the same restored residual root models with different types of adhesives separately.Results of von Mises stress analysis showed that the adhesives with low Young’s modulus can protect the root canal effectively.However,a root canal concentration is apparently produced around the root canal orifice when chewing.Adhesives with large Young’s modulus can buffer the stress concentration of the root canal orifice.However,the root canal tissue may be destroyed because the adhesive is too hard to buffer the load.

Considerations in the management of single-piece intraocular lenses outside the capsular bag

AIM: To investigate the outcomes of off label singlepiece acrylic intraocular lenses(SPA-IOL) ciliary sulcus placement compared to three-piece IOL(3P-IOL). METHODS: The charts of eight consecutive eyes of patients who received sulcus-placed SPA-IOLs between 2006 and 2009 were reviewed. None of the patients underwent IOL exchange. Charts of six age-matched patients who received sulcus placed 3P-IOLs were reviewed as a control group. RESULTS: Mean follow up was 16 mo for SPA-IOL and 23 mo for 3P-IOL. Five of 8 patients in the SPA-IOL group required chronic use of IOP lowering medications at final follow up. Of these, one patient needed glaucoma implant surgery for uncontrolled IOP. One patient in the 3P-IOL group used chronic aqueous suppression pre- and postoperatively. Four of eight eyes with SPAIOL were treated with chronic topical steroids and or non-steroidal anti-inflammatory drugs for cystoid macu-la edema, chronic uveitis, pigment dispersion syndrome or a combination of the above, compared to none in the control group. Mean best-corrected visual acuity was 20/35 in the SPA-IOL group and 20/47 in the 3PIOL group.CONCLUSION: Sulcus placed SPA-IOLs are associated with increased ocular morbidity. In select cases good visual acuity may be achieved. Due to postoperative rotation of sulcus placed toric SPA-IOLs stable astigmatism correction cannot be achieved. Alternative intraocular lenses should be considered when in-the-bag placement of SPA-IOL is not possible.

低水平PSV和T-piece自主呼吸试验在预撤机COPD患者中的应用价值

目的研究低水平压力支持通气(PSV)和T管(T-piece)自主呼吸试验(SBT)在预撤机慢性阻塞性肺疾病(COPD)患者中的应用价值。方法纳入2016年9月至2019年9月于联勤保障部队第904医院收治的88例行有创呼吸机通气的COPD患者为研究对象,按照随机数表法分为2组,各44例,其中观察组采用低水平PSV试验,对照组采用T-piece试验。比较两组SBT结局及SBT成功患者撤机结局,分析两组SBT过程中呼吸力学参数变化,包括呼吸频率(RR)、潮气量(VT)、气道闭合压(P0.1)、最大吸气压(Pimax)、氧饱和度(SaO2)、氧合指数(OI)及浅快呼吸指数(RSBI),并观察两组气道保护能力及两组患者临床结局。结果观察组SBT成功率为88.64%,显著高于对照组的70.45%(P<0.05);观察组撤机成功率为87.18%,显著高于对照组的77.42%(P<0.05)。观察组SBT30min时RSBI、Pimax、RR显著低于对照组(P<0.05),SaO2、VT显著高于对照组(P<0.05),OI、P0.1与对照组比较差异无统计学意义(P>0.05)。观察组气道内分泌物量、气道内吸痰频率显著低于对照组(P<0.05),咳嗽力量较对照组比较差异无统计学意义(P>0.05)。观察组总机械通气时间、ICU住院时间、总住院时间及呼吸机相关肺炎发生率、ICU病死率,较对照组比较差异无统计学意义(P>0.05)。结论预撤机COPD患者采用低水平PSV自主呼吸试验优于T管试验。

Single Piece Dental Implant: A Remedy for Atrophic Ridges: Review

Implant placement in severely atrophic jaws is especially challenging because of the poor quality and quantity of the future implant bed. Although various bone augmentation procedure like ridge augmentation, sinus lift these procedures are possible today but it may lead to surgical morbidity they increase the risks and costs of dental implant treatment as well as the number of necessary operations. Also sometimes the patient is not agreeing for such extensive surgical procedures, according to the well-known implantological rules for dental restorations, crestal implants are indicated in situations when an adequate vertical bone supply is given but single piece dental implant (basal implants) is a viable treatment option derives support from the basal bone area which usually remains free from the infection and less prone to resorption.

Ocular hypertension secondary to obesity: cortisol, the missing piece of the pathophysiological puzzle?

Dear Editor,Obesity has nowadays become a global public health challenge due to its rapidly growing prevalence and interconnection with a wide spectrum of comorbidities.

Ten Years Dedication Blossom on the Delicate Piece——Ordifen Cup 2014 China Lingerie Design ContestLaunches in Beijing

In the afternoon of October 29th,2014,Ordifen Cup 2014 China Lingerie Design Contest unveiled during China Fashion Week.Jointly held by China Fashion Association and Ordifen International Group,the contest presented us a grand feast with the essence of Ordifen’s ten years dedication.Tiny but delicate,the lingerie condenses the charisma of both culture and fashion in the small piece of cloth.Time goes so fast all in the blink of an eye.

A systematic review and meta-analysis to compare the effects of Chinese herbal pieces and granule in different diseaseherbal pieces

Objective:Compared to Chinese herbal piecesherbal pieces,the quality of TCM granule is stable and controllable,it is also a convenient alternative to decocting herbs.However,whether they are as clinically effective as Chinese herbal piecesherbal pieces is still controversial.In this study,a systematic review and meta-analysis were performed to assess the clinical efficacy of TCM granules and Chinese herbal piecesherbal pieces.Methods:A search of online databases for eligible articles was performed,including PubMed,Embase,Cochrane Library,Web of Science,China National Knowledge Internet,WanFang,and Chongqing VIP Information,searching from the inception of these databases to 2020.The Cochrane Handbook 5.1.0 was used to independently identify the trials,extract data,and assess the risk of bias.The meta-analysis was performed via RevMan 5.3 software.Results:A total of 98 eligible articles were included.After classification and statistical analysis of the related diseases,a meta-analysis was performed on 8 types of illnesses(cold,hypertension,migraine,osteoporosis,and diseases of the digestive system,such as gastritis,gastric ulcer,colitis,epigastric pain)included in 66 randomized controlled trials to compare the clinical efficacy and adverse events of TCM granules and Chinese herbal pieces.Meta-analysis showed that compared with Chinese herbal piecesherbal pieces,TCM granules had similar effectiveness and safety in treating cold,hypertension,and osteoporosis,but a higher response rate in migraines and a better effect in reducing migraine duration and higher response rate on diseases of the digestive system.Conclusion:Compared with the traditional decoctions,TCM formula granules had the same efficacy and safety,moreover,they had higher efficacy and safety in treating migraines and digestive system diseases.

基于SentencePiece的中医学分词模型建模研究

目的:探索构建适用于中医学领域的分词模型。方法:采用基于SentencePiece的无监督学习分词方法,提出利用出版教材、名家著作及中医临床病历这3种不同类型的文献构建中医学分词模型;选择中医临床病历、名医医案作为测试集进行模型测试。结果:中医学分词模型在测试集中的Kappa系数为0.79(一致性程度很高),准确率为0.84,宏观精确率为0.84,宏观召回率为0.83,宏观f1得分为0.83。结论:所构建的分词模型对于中医学专业术语有着较好的切分效果,表明该方法可运用于中医学领域的分词模型的构建,可为进一步地研究中医学分词提供方法学参考。

寻找日本连载动画《One Piece》成功的钥匙

《One Piece》又名《海贼王》,于1997年开始连载以来,其影响力不容小觑,被誉为日本三大国民动漫之一。这是一部连载超过十年的动画作品,本文试从创作者、叙事、文化、配乐等方面浅析《One Piece》成功的原因。