Rate-distortion optimized frame dropping and scheduling for multi-user conversational and streaming video

We propose a Rate-Distortion (RD) optimized strategy for frame-dropping and scheduling of multi-user conversa- tional and streaming videos. We consider a scenario where conversational and streaming videos share the forwarding resources at a network node. Two buffers are setup on the node to temporarily store the packets for these two types of video applications. For streaming video, a big buffer is used as the associated delay constraint of the application is moderate and a very small buffer is used for conversational video to ensure that the forwarding delay of every packet is limited. A scheduler is located behind these two buffers that dynamically assigns transmission slots on the outgoing link to the two buffers. Rate-distortion side information is used to perform RD-optimized frame dropping in case of node overload. Sharing the data rate on the outgoing link between the con- versational and the streaming videos is done either based on the fullness of the two associated buffers or on the mean incoming rates of the respective videos. Simulation results showed that our proposed RD-optimized frame dropping and scheduling ap- proach provides significant improvements in performance over the popular priority-based random dropping (PRD) technique.

A Novel Algorithm of Solving the Optimal Slope on Rate-distortion Curve for the Given Rate Budget

Rate-distortion optimization greatly improves the performance of compression coding system so that it pervades all of the source coding from an informationtheoretic standpoint and for the design of practical coding systems. For the case of rate-distortion optimization, Lagrange multiplier method provides the efficient and nearly optimal solution. In this paper, a fast and efficient algorithm is proposed to solve the optimal slope λ＊ of the rate-distortion curve at the given bit budget. Based on Lagrange multiplier method, the presented algorithm find λ＊ using the golden-ratio search. Compared with the Bisection method that only adapts to the system with the dense operational points on the rate-distortion curve, the proposed algorithm can be adapted to the system whether the operational points are populated densely or not. Thus it can be applied to both the wavelet coding system and the video coding standards such as H. 264, where Bisection method can not work well. In particular, the algorithm has been verified on the platform of the quadtree classified and trellis coded quantized （QTCQ） wavelet image compression system and the newest video coding standard H. 264. The experimental results are provided to demonstrate the efficiency of the algorithm. The proposed algorithm can improve the performance. A gain abour 0.6 - 0.7 dB can be achieved with the same rate in H. 264. In addition, it converges as fast as Bisection method, with almost the same ctinplexity.

Rate-distortion optimized bitstream switching for peer-to-peer live streaming

Peer-to-peer (P2P) technology provides a cost-effective and scalable way to distribute video data. However, high heterogeneity of the P2P network, which rises not only from heterogeneous link capacity between peers but also from dynamic variation of available bandwidth, brings forward great challenge to video streaming. To attack this problem, an adaptive scheme based on rate-distortion optimization (RDO) is proposed in this paper. While low complexity RDO based frame dropping is exploited to shape bitrate into available bandwidth in peers, the streamed bitstream is dynamically switched among multiple available versions in an RDO way by the streaming server. Simulation results show that the proposed scheme based on RDO achieves great gain in overall perceived quality over simple heuristic schemes.

A rate-distortion optimized rate shaping scheme for H.264 data partitioned video bitstream

To enable quality sealability and further improve the reconstructed video quallty m rate shaping, a rate-distortion optimized packet dropping scheme for H. 264 data partitioned video bitstream is proposed in this paper. Some side information is generated for each video bitstream in advance, while streaming such side information is exploited by a greedy algorithm to optimally drop partitions in a rate-distortion optimized way. Quality sealability is supported by adopting data partition instead of whole frame as the dropping unit. Simulation resuhs show that the proposed scheme achieves a great gain in the reconstructed video quality over two typical frame dropping schemes, with the help of the fine granularity in dropping unit as well as rate-distortion optimization.

关联规则分析中兴趣度量Lift与Conviction的关系探讨及教育数据验证

关联规则分析是数据挖掘中最常用的研究方法之一。在关联关系的发现过程中兴趣度量是关联规则发现的理论基础,它可以度量规则的重要程度,其中Lift和Conviction这两个度量在数据分析中被广泛应用于筛选关联规则。本文对这两种兴趣度量进行了研究。首先,提出并证明了当后项集固定时,Conviction取值随Lift取值单调增加,且Conviction (Lift)是一个凸函数。然后,证明了当Confidence固定时,Conviction取值随Lift取值单调增加,且Conviction (Lift)是一个凹函数。最后,综合以上两个方面,得到一个重要结论:当后项集保持不变或当Confidence固定时,根据Conviction和Lift筛选出来的规则都是相同的。最后,利用某高校数学类专业三个年级的成绩数据进行了定理及相应结论的验证。

Study of the Lift Force Induced by An Interceptor on A High-Speed Mono-Hull:The Affecting Factors and Estimation Formula

To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different conditions.Different lift forces are obtained by numerical calculations and validated by a model test in a towing tank.The factors that influence the force are the interceptor height,velocity,draft,and deadrise angle.The relationship between each factor and the induced lift force is investigated and obtained.We found that the induced lift mainly depends on the interceptor height and advancing velocity,and is proportional to the square of the interceptor height and velocity.The results also showed that the effects of the draft and deadrise angle are relatively less important,and the relationship between the induced lift and these two factors is generally linear.Based on the results,a formula including the combined effect of all factors used to estimate the lift force induced by the interceptor is developed based on systematic analysis.The proposed formula could be used to estimate the lift force induced by interceptors,especially under high-speed condition.

A comparative study on kinetics and dynamics of two dump truck lifting mechanisms using MATLAB simscape

In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding stages.The simulation findings are compared to the analytical calculation results in the steady state,and both methods show good agreement.In the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model 2.Meanwhile,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting stage.The established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system operation.It is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems.

改良LIFT手术联合自体富血小板PRP凝胶技术治疗肛瘘的临床研究

目的:探讨改良括约肌间瘘管结扎术(LIFT)手术联合自体富血小板PRP凝胶技术治疗肛瘘的临床疗效。方法:随机将2021年5月至2023年5月在我院接受治疗的62例肛瘘患者分为对照组和观察组,31例一组。对照组采用改良LIFT手术治疗,观察组予以改良LIFT手术联合自体富血小板PRP凝胶技术治疗。随访两个月,比较两组住院时间,创面愈合时间,创面瘢痕面积,临床疗效,术后疼痛评分,肛门功能评分,并发症发生率。结果:观察组的住院时间和创面愈合时间均短于对照组,创面瘢痕面积少于对照组(P<0.05)。观察组治疗有效率为96.77%,高于对照组的80.65%(P<0.05)。观察组术后1天、7天VAS评分及术后1、2个月Wexner评分均低于对照组(P<0.05)。观察组术后并发症发生为6.45%,低于对照组的25.81%(P<0.05)。结论:肛瘘采用改良LIFT手术联合自体富血小板PRP凝胶技术治疗效果突出,可以缓解术后疼痛,改善肛门功能,减少并发症,促进预后恢复,值得临床推广应用。

Analysis of Maximum Liquid Carrying Capacity Based on Conventional Tubing Plunger Gas Lift

China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable productionof these gas wells, plunger-lift technology plays an important role. In order to fully understand and accurately graspthe drainage and gas production mechanisms of plunger-lift, a mechanical model of plunger-liquid column uplift inthe plunger-lift process was established, focusing on conventional plunger-lift systems and representative wellboreconfigurations in the Linxing region. The operating casing pressure of the plunger-lift process and the calculationmethod for the maximum daily fluid production rate based on the work regime with the highest fluid recovery ratewere determined. For the first time, the critical flow rate method was proposed as a constraint for the maximumliquid-carrying capacity of the plunger-lift, and liquid-carrying capacity charts for conventional plunger-lift withdifferent casing sizes were developed. The results showed that for 23/8 casing plunger-lift, with a well depth ofshallower than 808 m, the maximum drainage rate was 33 m3/d;for 27/8 casing plunger-lift, with a well depth ofshallower than 742 m, the maximum drainage rate was 50.15 m3/d;for 31/2 casing plunger-lift, with a well depthof shallower than 560 m, the maximum drainage rate was 75.14 m3/d. This research provides a foundation for thescientific selection of plunger-lift technology and serves as a decision-making reference for developing reasonableplunger-lift work regimes.

Trajectory compensation for multi-robot coordinated lifting system considering elastic catenary of the rope

The multi-robot coordinated lifting system is an unconstrained system with a rigid and flexible coupling.The deformation of the flexible rope causes errors in the movement trajectory of the lifting system.Based on the kinematic and dynamic analysis of the lifting system,the elastic catenary mod-el considering the elasticity and mass of the flexible rope is established,and the effect of the deform-ation of the flexible rope on the position and posture of the suspended object is analyzed.According to the deformation of flexible rope,a real-time trajectory compensation method is proposed based on the compensation principle of position and posture.Under the lifting task of the low-speed move-ment,this is compared with that of the system which neglects the deformation of the flexible rope.The trajectoy of the lifting system considering the deformation of flexible rope.The results show that the mass and elasticity of the flexible rope can not be neglected.Meanwhile,the proposed trajectory compensation method can improve the movement accuracy of the lifting system,which verifies the ef-fectiveness of this compensation method.The research results provide the basis for trajectory plan-ning and coordinated control of the lifting system。

Research on the Lifting Path of Data Literacy Ability of Applied University Teachers under the Perspective of Organizational Learning

With the arrival of the big data era, the modern higher education model has undergone radical changes, and higher requirements have been put forward for the data literacy of college teachers. The paper first analyzes the connotation of teacher data literacy, and then combs through the status quo and dilemmas of teachers’ data literacy ability in applied universities. The paper proposes to enhance the data literacy ability of teachers from the perspective of organizational learning. Through building a digital culture, building a data-driven teaching environment, and constructing an interdisciplinary learning community to further promote the application of the theory and practice of datafication inside and outside the organization, and ultimately improve the quality of teaching.

消肿生肌汤辅助LIFT对高位单纯性肛瘘术后疼痛与康复进程的影响

目的:研究消肿生肌汤辅助经括约肌间瘘管结扎术(Ligation of intersphincteric fistula tract,LIFT)对高位单纯性肛瘘术后疼痛(Visual analogue scale,VAS)评分、康复进程的影响.方法:选取2020年8月至2022年8月于我院确诊的94例肛瘘患者作为研究对象,依随机对照法分为研究组和对照组,各47例.对照组采用LIFT术治疗,研究组在对照组基础上联合消肿生肌汤治疗.比较两组临床疗效、治疗后恢复情况及住院时间、治疗前后视觉模拟评分(VAS)、大便失禁严重性指数(Fecal incontinence severity index,FISI)、Wexner肛门失禁评分(Wexner)、肛肠动力学、相关血清指标水平.结果:研究组总有效率高于对照组(P<0.05);治疗后,研究组VAS、FISI、Wexner评分均低于对照组(P<0.05);研究组直肠静息压(Rectal resting pressure,RRP)、肛管最大收缩压(Analmaximal contraction pressure,AMCP)、肛管静息压(Anal tube resting pressure,ARP)、肛管最长收缩时间(Anal longest contraction,ALCT)水平高于对照组(P<0.05);研究组血清转化生长因子-β1(Transforming growth factor-β1,TGF-β1)、纤维连接蛋白(Fibronectin,FN)高于对照组,淀粉样蛋白A(Serum amyloid A,SAA)、趋化因子5(Chemokine ligand 5,CCL5)低于对照组(P>0.05);研究组恢复情况及住院时间短于对照组(P<0.05).结论:消肿生肌汤辅助LIFT对高位单纯性肛瘘患者术后效果显著,可有效促进患者创口愈合,减少炎症反应,降低肛肠疼痛度,缩短临床康复进程.

lift⁃off制程PEB温度对负性光阻显影后截面Profile的影响

本文研究了lift⁃off(揭开-剥离)制程曝光后烘烤温度(post exposure bake,PEB)对负性光阻显影截面Profile(光刻胶结构)的影响。结果表明:在保留原有PEB盘面加热的方式前提下通过增加PEB盘盖加热功能进行烘烤,通过控制PEB盘面温度可调整光阻关键尺寸(critical dimension,CD)及截面Profile形貌,通过控制PEB盘盖加热可调整截面Profile光阻顶端形貌及强度,可显著改善负性光阻显影后截面Profile难以调整的问题。另外,不同的盘面温度、不同盘盖温度以及不同的显影时间相互配合,可以实现一种负性光阻产生不同截面光刻胶结构效果,可以实现同种光阻lift⁃off制程多样化。

Abdominoplasty, Liposuction and Brazilian Butt Lift (BBL) in Kinshasa in the Democratic Republic of Congo. My Experience in This Aesthetic Plastic Surgery with Black African Women in a Low-Income Country

Background: In low-income African countries, the demand and use of plastic surgery operations including abdominoplasty, liposuction and Brazilian butt lift (BBL) are increasing. The goal of this work is to present my experience and the challenges of this aesthetic plastic surgery among black African women. Material and Methods: A retrospective study was conducted about the abdominoplasties, liposuctions and Brazilian butt lift (BBL) which I operated in public and private hospitals at Kinshasa (Democratic Republic of Congo) in black African women. It covers a period of 13 years, going from December 1, 2010 to December 1, 2023. For this study, I had at least 6 months period (to Juin 1, 2024) to assess the occurrence of early and late postoperative complications. Results: I performed 84 abdominoplasties, 144 liposuctions and 23 Brazilian butt lifts (BBL). The average age at the time of abdominoplasty was 44 years with extremes ranging from 26 to 55 years and a concentration of cases (60.7%) in the age group of 40 to 49 years. The age group of 20 to 29 years old represented the lowest rate of requests for abdominoplasty (4.7%). Patients with a BMI of 30 to 2 were the majority (61.9%), followed by those between 25 to 2 (29.7%). 67.8% of patients were obese (BMI ≥ 30 kg/m2). The average age at the time of liposuction was 41 years with extremes ranging from 21 years to 69 years;and more than half of cases (68%) in the age group between 30 and 49 years. As for Brazilian butt lift (BBL), the average age was 33 years with extremes ranging from 24 to 42 years and a concentration of patients (91.3%) between 20 and 39 years. The immediate postoperative complications of abdominoplasties observed were: seroma in 7% of cases, hematoma and partial infection of the surgical site in 5% of cases. Pathological scars (hypertrophic, keloid) after abdominoplasties were observed in 9% of cases. The most common complication of liposuction was contour deformity. I observed 16 patients (11.1%) with soft-tissue depressions or elevations, skin panniculus or folds. For Brazalian Butt Lift (BBL), complications like asymmetry for 2 patients (8.9%), contour irregularities for 2 patients (8.9%), and excessive fat removal for 6 patients (26%), had observed. I have not recorded any cases of death or pulmonary embolism. Conclusion: I perform aesthetic plastic surgery procedures in black African women with a high socioeconomic standard of living compared to the average of the general population. The renunciation of planned surgery is motivated by the impossibility of paying the cost of the operation as well as by popular and religious perceptions regarding cosmetic surgery. The results of these aesthetic plastic surgery procedures carried out are very satisfactory for them. The challenges to overcome are mainly threefold: the unforeseeable complications of these cosmetic plastic surgery procedures, popular and religious perceptions of cosmetic surgery as well as the poverty of the population.

LIFT去噪方法在低信噪比资料处理中的应用

传统去噪一般都是通过各种方法将原始数据分离为有效信号和噪声,从而达到去噪目的,在去噪的过程中,忽略了信号保真的处理原则,在去掉噪声的同时有可能也损害了有效信号。这里从传统去噪方法存在的问题入手,通过对传统去噪方法的原理分析,研究了LIFT去噪技术。LIFT去噪的核心是首先建立信号模型,然后将原始地震信号和信号模型相减,求得剩余信号。通过对剩余信号进行针对性的去噪处理,去除剩余信号中存在的噪声,然后再与信号模型进行合并重构,得到新的具有高信噪比、高保真的地震信号。将该方法在低信噪比地震资料处理中进行了实例测试,取得了理想的应用效果。

内口结扎改良LIFT术治疗低位肛瘘的临床研究

目的观察内口结扎改良LIFT术治疗低位肛瘘的疗效及术后并发症。方法将120例低位肛瘘患者随机分为治疗组与对照组,各60例,治疗组行内口结扎改良LIFT术,对照组行肛瘘切除术。结果两组治愈率均为100%,差异无统计学意义(P<0.05);治疗组术后肛门功能评分为(1.02±0.17)分,低于对照组的(1.08±0.12)分,两组比较,差异有统计学意义(P<0.05)。治疗组患者愈合时间、住院费用、疤痕大小均优于对照组(P<0.05)。结论内口结扎改良LIFT术治疗低位肛瘘疗效满意,且能缩短愈合时间、缩小疤痕大小、减轻术后肛门功能损伤、节省住院费用。

一种生成双正交紧支复小波的Lifting方法

提出了一种构造双正交紧支复小波的方法 :以现有任何一种正交或双正交实小波为基础 ,可构造出消失矩阶数可任意选定的无穷多个相频特性 (包括线性相位特性 )不同的双正交紧支复小波。其特点为 :由于是双正交紧支型 ,可采用Mallat算法等快速算法 ,因此使用时实时性好 ;因为是复小波 ,所以能提取电力系统至关重要的相位信息 ;具有多种相频特性 ,便于与相频特性多变的电力系统信号匹配等 ,因此这类小波在电力系统有广泛的应用前景。

基于LIFT思想的噪声压制技术在南极海域地震资料中的应用

在中国第33次南极科学考察中,自然资源部中国地质调查局下属的广州海洋地质调查局"海洋六号"船于2016年12月到2017年2月在南极半岛南设得兰海沟海域获得了1 400多km的高分辨率多道地震资料。资料存在的主要噪声为异常高能量干扰和多次波干扰,为了高保真的压制噪声,在最大限度地保护有效信号的前提下充分地压制噪声,设计了基于LIFT(Linear Interference Filter Technique)思想的噪声压制方法。利用这套方法分别针对异常高能量干扰和多次波干扰进行了压制,压制结果显示,噪声得到了很好的压制,有效信号得到了很好的保护,达到了高保真去噪的目的。

LIFT术在肛瘘治疗中的应用

目的探讨结扎括约肌间瘘管术(LIFT)对肛瘘的临床疗效。方法对50例肛瘘管患者行LIFT术,并结合术中所见以及术后随访对LIFT术的疗效进行评价。结果经LIFT术治疗的肛瘘患者,随访3～6个月,仅3例出现复发,术后未发生肛门失禁。结论 LIFT术操作简便,疗效显著,不损伤括约肌功能,是治疗肛瘘的有效方法。

肛瘘治疗中LIFT术的临床应用与展望

肛瘘是肛管直肠疾病中的常见病，主要由肛腺感染引起。目前仍是以手术治疗为主，在过去的6年里，经括约肌间瘘管结扎术（LIFT）作为一种易操作、创伤小、费用低，并且完全保留括约肌功能的新术式，越来越受到关注。但是，由于LIFT术的临床应用较少，也出现效果差异大、不明原因失败、复发等问题。本文经检索国内外文献后对LIFT术在临床的应用及进展做一分析并综述。