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Giant vesical diverticulum:A rare cause of defecation disturbance

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World Journal of Gastroenterology 2009年第31期15卷 3957-3959页

作者： Sami Akbulut Bahri Cakabay Arsenal Sezgin kenan Isen Ayhan Senol Department of Surgery Diyarbakir Education and Research Hospital Department of Pathology Diyarbakir Education and Research Hospital Department of Urology Diyarbakir Education and Research Hospital Department of Radiology Diyarbakir Education and Research Hospital

Vesical diverticula frequently result from bladder outlet obstructions. However, giant vesical diverticula which cause acute abdomen or intestinal obstruction are very rare. Our review of the English medical literature found 3 cases of bladder diverticula which caused gastrointestinal symptoms. Here, we present a 57-year-old man with a giant diverticulum of the urinary bladder who complained of abdominal pain, nausea and vomiting, constipation, no passage of gas or feces, and abdominal distension for 3 d. A 20 cm×15 cm diverticulum was observed upon laparotomy. The colonic obstruction was secondary to external compression of the rectum against the sacrum by a distended vesical diverticulum. We performed a diverticulectomy and primary closure. Twelve months postoperatively, the patient had no difficulty with voiding or defecation.

关键词：膀胱排便扰民医学文献肠梗阻胃肠道腹部腹痛

Steganalysis of Low Embedding Rate CNV-QIM in Speech

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Computer Modeling in Engineering & Sciences 2021年第8期128卷 623-637页

作者： Wanxia Yang Miaoqi Li Beibei Zhou Yan Liu kenan Liu Zhiyu Hu Mechanical and Electrical Engineering College Gansu Agricultural UniversityLanzhou730070China

To address the difficulty of detecting low embedding rate and high-concealment CNV-QIM(complementary neighbor vertices-quantization index modulation)steganography in low bit-rate speech codec,the code-word correlation model based on a BiLSTM(bi-directional long short-term memory)neural network is built to obtain the correlation features of the LPC codewords in speech codec in this ***,softmax is used to classify and effectively detect low embedding rate CNV-QIM steganography in VoIP *** experimental results show that for speech steganography of short samples with low embedding rate,the BiLSTM method in this paper has a superior detection accuracy than state-of-the-art methods of the RNN-SM(recurrent neural network-steganalysis model)and SS-QCCN(simplest strong quantization codeword correlation network).At an embedding rate of 20%and a duration of 3 s,the detection accuracy of BiLSTM method reaches 75.7%,which is higher than that of RNNSM by 11.7%.Furthermore,the average testing time of samples(100%embedding)is 0.3 s,which shows that the method can realize real-time steganography detection of VoIP streams.

关键词： CNV-QIM steganography BiLSTM steganalysis VoIP speech

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怪娃娃凯特·麦克金农

环球银幕 2023年第9期 118-121页

作者： kenan 不详

《芭比》里哪个芭比最让人印象深刻?肯定是“怪芭比”啊!她是一个生理和心理状态都很不正常的芭比。你小时候玩坏过娃娃吗?你会把娃娃的腿劈叉到头顶吗?你会在她脸上乱抹瞎画吗?于是怪芭比就这样诞生了。她虽然很怪,却像《黑客帝国》里... 详细信息

《芭比》里哪个芭比最让人印象深刻?肯定是“怪芭比”啊!她是一个生理和心理状态都很不正常的芭比。你小时候玩坏过娃娃吗?你会把娃娃的腿劈叉到头顶吗?你会在她脸上乱抹瞎画吗?于是怪芭比就这样诞生了。她虽然很怪,却像《黑客帝国》里的墨菲斯一样,引导着主角走向觉醒,可谓是整个故事中至关重要的一环。谢天谢地,导演格蕾塔·葛韦格在童年回忆的基础上灵光一现,创造了这个角色。哈利路亚,这个角色交给了凯特·麦克金农。

关键词：哈利路亚《黑客帝国》童年回忆金农生理和心理印象深刻芭比娃娃

基于改进RRT^(*)算法的无人机往返航迹规划

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中国科学:技术科学 2023年第11期53卷 1911-1921页

作者：俞宬陈谋雍可南南京航空航天大学自动化学院南京211106

针对无人机(unmanned aerial vehicle,UAV)在低空复杂未知环境下的航迹规划问题,充分考虑去程与返程过程中信息的不对称特性,本文提出一种UAV往返航迹规划算法.去程规划通过UAV机载设备实时探测不断更新环境信息,并利用改进的B-RRT*(bid... 详细信息

针对无人机(unmanned aerial vehicle,UAV)在低空复杂未知环境下的航迹规划问题,充分考虑去程与返程过程中信息的不对称特性,本文提出一种UAV往返航迹规划算法.去程规划通过UAV机载设备实时探测不断更新环境信息,并利用改进的B-RRT*(bidirectional rapidly-exploring random tree*)算法结合滚动规划生成去程航迹.返程规划根据去程航迹与全局环境信息,限制在由航迹起始点和目标点确定的椭圆子集中进行集中采样,并采用三次B样条插值算法对规划航迹进行平滑处理生成返程航迹.仿真结果表明所研究的改进算法能有效实现去程与返程的航迹规划.最后,搭建四旋翼UAV平台进行UAV避障飞行实验,验证了本文所提算法的有效性.

关键词：无人机 B-RRT*算法滚动规划航迹规划航迹平滑

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基于迁移学习的铣削机器人定位误差补偿方法

机械工程学报 2022年第14期58卷 170-180页

作者：邓柯楠高栋马守东路勇哈尔滨工业大学机电工程学院哈尔滨150000

空间网格补偿法是提高机器人定位误差的有效方法之一,然而由于所需采样位姿多导致误差测量环节非常耗时,为提高机器人定位误差补偿效率,提出了一种机理分析与数据驱动的铣削机器人定位误差补偿方法,基于迁移学习来预测机器人工作空间内... 详细信息

空间网格补偿法是提高机器人定位误差的有效方法之一,然而由于所需采样位姿多导致误差测量环节非常耗时,为提高机器人定位误差补偿效率,提出了一种机理分析与数据驱动的铣削机器人定位误差补偿方法,基于迁移学习来预测机器人工作空间内不同区域的定位误差。首先建立机器人刚柔耦合误差模型,研究立方体与柱体工作空间内不同区域的误差分布特性;之后,考虑误差区域相似性将机器人工作空间分为源域空间与目标域空间,在源域空间基于分级采样策略将完备的机器人采样位姿及误差测量数据作为源域数据,对于目标域空间只需要将少量的采样位姿及误差数据作为目标域数据,源域数据与目标域数据均用于训练高斯过程回归模型,通过基于加权拟合误差的子空间对齐和自适应权重迭代方法提升迁移学习模型预测精度,根据指定机器人位姿参数预测并补偿机器人定位误差;最后,使用KR160铣削机器人系统进行了误差补偿试验以验证该方法的可行性和有效性,试验结果表明,经过补偿后机器人定位误差1.499 mm降低到0.182 mm,所需机器人采样位姿数目减少了70%,使用铣削机器人加工法兰孔,其轮廓误差和位置误差达到0.269 mm和0.331 mm,该方法可以提高补偿效率和机器人定位精度。

关键词：定位误差迁移学习铣削机器人补偿效率耦合误差模型

Measuring County Resilience After the 2008 Wenchuan Earthquake

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International Journal of Disaster Risk Science 2016年第4期7卷 393-412页

作者： Xiaolu Li Nina Lam Yi Qiang kenan Li Lirong Yin Shan Liu Wenfeng Zheng School of Automation University of Electronic Science and Technology of China Department of Environmental Sciences Louisiana State University The Earth Lab University of Colorado Boulder Geographical & Sustainability Sciences Department University of Iowa

The catastrophic earthquake that struck Sichuan Province,China,in 2008 caused serious damage to Wenchuan County and surrounding areas in southwestern *** recent years,great attention has been paid to the resilience of the affected *** study applied the resilience inference measurement(RIM) model to quantify and validate the community resilience of 105 counties in the impacted *** RIM model uses cluster analysis to classify counties into four resilience levels according to the exposure,damage,and recovery *** model then applies discriminant analysis to quantify the influence of socioeconomic characteristics on the county's *** results show that counties located at the epicenter had the lowest resilience,but counties immediately adjacent to the epicenter had the highest resilience *** that were farther away from the epicenter returned to normal resiliency *** variables—including sex ratio,per capita GDP,percent of ethnic minority,and medical facilities—were identified as the most influential characteristics influencing *** study provides useful information to improve county resilience to earthquakes and support decision making for sustainable development.

关键词： China Resilience Resilience inference measurement(RIM) model Vulnerability Wenchuan earthquake

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多旋翼无人机模型预测抗扰避障制导

国防科技大学学报 2022年第4期44卷 32-42页

作者：兰庆湘陈谋雍可南南京航空航天大学自动化学院江苏南京211100

多旋翼无人机的自主避障是完成复杂任务的基础,避障的效果直接影响无人机执行任务的效能。针对存在外部扰动的无人机避障问题,提出了一种基于模型预测的抗扰避障制导律设计方法。通过设计干扰观测器对系统动态中的外部干扰进行了估计,... 详细信息

多旋翼无人机的自主避障是完成复杂任务的基础,避障的效果直接影响无人机执行任务的效能。针对存在外部扰动的无人机避障问题,提出了一种基于模型预测的抗扰避障制导律设计方法。通过设计干扰观测器对系统动态中的外部干扰进行了估计,并基于李雅普诺夫函数方法设计辅助制导律用于建立稳定性约束条件。结合前两者与模型预测控制,在模型预测控制优化求解中考虑无人机与障碍物的关系,根据所设计的制导律求解水平线速度与偏航角速度指令实现无人机的避障。对所提出的避障制导律进行数值仿真和实物飞行验证,结果表明了所提方法的有效性。

关键词：多旋翼无人机避障制导模型预测控制干扰观测器

Reaching proficiency in laparoscopic splenectomy

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World Journal of Gastroenterology 2009年第32期15卷 4005-4008页

作者： Tarik Zafer Nursal Ali Ezer Sedat Belli Alper Parlakgumus kenan Caliskan Turgut Noyan Department of General Surgery University of BaskentDadaloglu Mah.01200Serin Evler 39.Sk.No.6 Yüregir/AdanaTurkey

AIM:To investigate the proficiency level reached in laparoscopic splenectomy using the learning curve ***:All patients in need of splenectomy for benign causes in whom laparoscopic splenectomy was attempted by a single surgeon during a time period of 6 years were included in the study (n=33). Besides demographics, operation-related variables and the response to surgery were recorded. The patients were allocated to groups of five, ranked according to the date of the operation. Operation duration, complications, postoperative length of stay, conversion to laparotomy and splenic weight were then compared between these ***: There was a significant difference regarding operation times between the groups (P = 0.001). An improvement was observed after the first 5 cases. The learning curve was flat up to the 25th case. Following the 25th case the operation times decreased still further. There was no difference between the groups regarding the other ***: Unlike the widely accepted "L" shape, the learning curve for laparoscopic splenectomy is a horizontal lazy "S" with two distinct slopes. Privileges may be granted after the first 5 cases. However proficiency seems to require 25 cases.

关键词：切除术腹腔镜脾操作时间学习曲线人口统计手术并发症

Cooperative control of perpendicular magnetic anisotropy via crystal structure and orientation in freestanding SrRuO_(3)membranes

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npj Flexible Electronics 2022年第1期6卷 83-90页

作者： Zengxing Lu Yongjie Yang Lijie Wen Jiatai Feng Bin Lao Xuan Zheng Sheng Li kenan Zhao Bingshan Cao Zeliang Ren Dongsheng Song Haifeng Du Yuanyuan Guo Zhicheng Zhong Xianfeng Hao Zhiming Wang Run-Wei Li CAS Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051China Key Laboratory of Applied Chemistry College of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China University of Nottingham Ningbo 315201China Nano Science and Technology Institute University of Science and Technology of ChinaHefei 230026China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryHFIPSAnhuiChinese Academy of SciencesHefei 230031China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Flexible magnetic materials with robust and controllable perpendicular magnetic anisotropy(PMA)are highly desirable for developing flexible high-performance spintronic ***,it is still challenge to fabricate PMA films on polymers ***,we report a facile method for synthesizing single-crystal freestanding SrRuO_(3) membranes with controlled crystal structure and orientation using water-soluble Ca_(3-x)Sr_(x)Al_(2)O_(3)6 sacrificial *** cooperative effect of crystal structure and orientation,flexible membranes reveal highly tunable magnetic anisotropy from in-plane to out-of-plane with a remarkable PMA energy of 7×10^(6) erg·cm^(−3).First-principle calculations reveal that the underlying mechanism of PMA modulation is intimately correlated with structure-controlled Ru 4d-orbital occupation,as well as spin-orbital matrix element differences,dependent on the crystal *** addition,even after 10,000 bending cycles,the PMA keeps stable,indicating a robust magnetism reliability in the prepared *** work provides a feasible approach to prepare the flexible oxide films with strong and controllable PMA.

关键词： anisotropy magnetic structure