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CTA联合增强现实技术在股前外侧皮瓣术中的应用
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作者 李雪栋 田惠玲 +5 位作者 冯小辉 曹能力 胡晓宇 陈亚伟 窦邦现 刘建惠 《中国矫形外科杂志》 北大核心 2026年第6期558-562,共5页
[目的]介绍CTA联合增强现实技术在股前外侧皮瓣(anterolateral thigh flap,ALTF)术中应用的手术技术和初步临床结果。[方法]患者术前进行CTA检查,将数据以DICOM的数据格式导入计算机Mimics中,重建ALTF穿支和周围肌肉的三维图像模型,将... [目的]介绍CTA联合增强现实技术在股前外侧皮瓣(anterolateral thigh flap,ALTF)术中应用的手术技术和初步临床结果。[方法]患者术前进行CTA检查,将数据以DICOM的数据格式导入计算机Mimics中,重建ALTF穿支和周围肌肉的三维图像模型,将重建的图像模型导入手机Sina软件中。术中利用Sina软件,将重建出的虚拟的穿支三维信息投射到皮瓣供区,通过布样设计的方式进行皮瓣设计。手术屏幕实时显示影像学穿支信息和患者皮瓣供区,术中采用会师法沿大腿前外侧阔筋膜层游离皮瓣,分离穿支血管。最后,将皮瓣转移至受区,吻合附近的主干动脉伴行静脉,供区直接拉拢缝合或植皮。[结果]7例患者均顺利完成手术,术中均探查证实定位准确,术后移植皮瓣全部成活,无血管危象发生。皮瓣供区均I期愈合。术后随访6~15个月,皮瓣均成活。3例手部软组织缺损患者手功能按中华医学会手外科学会上肢部分功能评分均为良;4例足部软组织缺损患者AOFAS评分平均(56.5±5.1)分。[结论]CTA联合AR技术在ALTF术中定位准确,可简化手术操作,临床效果良好。 展开更多
关键词 股前外侧皮瓣 计算机断层血管成像 增强现实 术前定位
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基于深度学习的肝脏局灶性病变检测方法综述
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作者 董文益 杨伟东 +2 位作者 唐冰慧 王琦 肖宏宇 《图学学报》 北大核心 2026年第1期1-16,共16页
肝脏局灶性病变(FLLs)检测对疾病诊断和治疗至关重要。传统检测方法面临诸多挑战,深度学习技术的应用为其带来新契机。鉴于此,系统综述了基于深度学习的FLLs检测方法,通过深入分析相关技术的优势与不足,为FLLs检测技术的发展提供了具体... 肝脏局灶性病变(FLLs)检测对疾病诊断和治疗至关重要。传统检测方法面临诸多挑战,深度学习技术的应用为其带来新契机。鉴于此,系统综述了基于深度学习的FLLs检测方法,通过深入分析相关技术的优势与不足,为FLLs检测技术的发展提供了具体的研究方向。首先对肝脏放射影像的公开数据集进行了整理归纳,阐述数据预处理对提升模型性能的关键作用。其次,对比分析了基于卷积神经网络、Transformer以及知识蒸馏等技术的2D与3D检测算法,揭示了从局部特征建模到全局时空关联的技术演进路径。此外,深入探讨了针对多期相影像的时序特征融合方法,为动态病变表征提供了新思路。研究表明,现有方法在检测精度与效率上取得突破,但仍面临小病灶敏感性不足、跨设备泛化性弱及临床验证缺乏等挑战。未来研究需通过多中心数据协同、轻量化算法设计及可解释性增强等途径,加速深度学习在肝脏病变辅助诊断中的临床转化与应用。 展开更多
关键词 深度学习 肝脏局灶性病变 目标检测 计算机断层扫描 多期相
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针织纬编纵向凸条编织技术研究
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作者 刘鸣欢 高锡光 卢雪婷 《针织工业》 北大核心 2026年第1期11-14,共4页
文章研究纬编针织纵向凸条编织技术,包括以首针位、尾针位和至少两个且位于首针位和尾针位之间的中间针位作为纵向凸条编织位进行编织,通过多次分步的翻针、编织浮线和移圈的操作,确保凸起的效果和编织生产稳定性。该方法充分利用电脑... 文章研究纬编针织纵向凸条编织技术,包括以首针位、尾针位和至少两个且位于首针位和尾针位之间的中间针位作为纵向凸条编织位进行编织,通过多次分步的翻针、编织浮线和移圈的操作,确保凸起的效果和编织生产稳定性。该方法充分利用电脑横机双系统优势,编织时为降低编织难度,凸显凹凸效果,在一个完整花型中结合浮线编织,既补偿需要左右移圈的线圈长度,又使凸起部分两侧有一定的对比高度,可以有效代替手工缝合形成凸起的效果,机械化生产,不仅提高生产效率,产品一致性好,还解决人工缝合困难的问题。 展开更多
关键词 纬编 纵向凸条 编织技术 电脑横机 人工缝合
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PMPU-CAT Platform:面向青少年的问题性手机使用计算机自适应平台的研发
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作者 齐运晓 马苑秋 +1 位作者 高垚杰 刘拓 《心理与行为研究》 北大核心 2026年第1期103-112,共10页
本研究旨在开发一个基于JAVA语言的问题性手机使用的计算机化自适应测验平台。在平台开发过程中,采用贝叶斯期望后验估计作为能力估计的算法、最大信息量选题算法进行项目选择、标准误阈限值作为终止规则。通过模拟实验,将PMPU-CAT平台... 本研究旨在开发一个基于JAVA语言的问题性手机使用的计算机化自适应测验平台。在平台开发过程中,采用贝叶斯期望后验估计作为能力估计的算法、最大信息量选题算法进行项目选择、标准误阈限值作为终止规则。通过模拟实验,将PMPU-CAT平台与R平台和问题性手机使用传统纸笔测验的题目使用数量、测量误差以及测验信度进行对比,结果表明,PMPU-CAT平台具有良好的测验精度,并且其测验效率较高。该平台可以为教育与心理测评领域提供良好的技术支持。 展开更多
关键词 问题性手机使用 计算机化自适应测验 心理测评 PMPU-CAT
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给排水工程手算与电算对比分析
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作者 徐圣楠 《四川建材》 2026年第2期221-224,共4页
BIM技术以其三维可视化、虚拟化和数据化方面的优势而被用来推进未来建筑行业的工业化、信息化和智能化。为了研究数字化时代手算是否应被淘汰,通过将生产车间污水系统手算与电算过程做对比,研究了给排水工程算量计价的学习与应用方法... BIM技术以其三维可视化、虚拟化和数据化方面的优势而被用来推进未来建筑行业的工业化、信息化和智能化。为了研究数字化时代手算是否应被淘汰,通过将生产车间污水系统手算与电算过程做对比,研究了给排水工程算量计价的学习与应用方法。结果表明,手算是基础,软件是技术。工程造价人员不仅需要具备扎实的建筑材料、建筑结构、施工工艺等理论基础,而且要熟练掌握各种工程算量软件,只有掌握扎实的专业功底,不断学习、更新技能,才能赶上时代的高速发展。 展开更多
关键词 BIM技术 理论基础 手算 电算
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黄色肉芽肿性胆囊炎的CT、MRI征象及诊断分析
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作者 张英 曹亚娟 李剑 《中国CT和MRI杂志》 2026年第1期111-113,共3页
目的探讨黄色肉芽肿性胆囊炎(XGC)的CT、MRI征象及诊断分析。方法回顾性分析本院2020年1月至2024年1月40例XGC患者临床资料,纳入XGC组;另选取同期40例胆囊癌患者作为对照患者纳入胆囊癌组,所有患者均通过CT和(或)MRI检测,分析XGC影像学... 目的探讨黄色肉芽肿性胆囊炎(XGC)的CT、MRI征象及诊断分析。方法回顾性分析本院2020年1月至2024年1月40例XGC患者临床资料,纳入XGC组;另选取同期40例胆囊癌患者作为对照患者纳入胆囊癌组,所有患者均通过CT和(或)MRI检测,分析XGC影像学特征,对比XGC与胆囊癌影像学特征差异。结果XGC组40例患者均接受了CT检测,结果显示37例(92.50%)患者出现胆囊壁增厚(局限性7例,弥漫性30例),31例(77.50%)发现胆囊结石;28例(70.00%)增强扫描动脉期胆囊黏膜线连续;16例(40.00%)患者可见“夹心饼干征”。在20例接受了MRI检查的XGC患者中,20例(100.00%)患者出现胆囊壁增厚(局限性3例,弥漫性17例);18例(90.00%)出现胆囊结石;增强扫描显示,15例(75.00%)在动脉期胆囊黏膜连续;12例(60.00%)患者肝胆界面清晰可见。XGC组胆囊壁增厚且增厚类型为弥漫性增厚、胆囊壁“夹心饼干征”、胆囊壁内结节、胆囊壁黏膜线完整比例高于胆囊癌组,胆道梗阻、周围淋巴结肿大比例低于胆囊癌组(P<0.05)。结论XGC与胆囊癌在临床和CT、MRI影像学特征上重叠较多,综合分析患者临床表现及影像学特征对提升XGC术前诊断水平具有较高价值。 展开更多
关键词 黄色肉芽肿性胆囊炎 磁共振成像 电子计算机体层扫描 影像学特征
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精密选针压脚高效生产工艺的优化研究
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作者 何奇 潘锡源 丁建荣 《模具制造》 2026年第4期264-266,共3页
精密选针压脚是电脑横机核心件,其“细、长、薄”特性导致传统加工存在应力变形、精度不稳等瓶颈。构建了“材料适配-流程重构-精修矫正”三位一体冲压工艺体系。通过优化毛坯选材、分级热处理及精密矫正等九道工序,实现工艺革新。经正... 精密选针压脚是电脑横机核心件,其“细、长、薄”特性导致传统加工存在应力变形、精度不稳等瓶颈。构建了“材料适配-流程重构-精修矫正”三位一体冲压工艺体系。通过优化毛坯选材、分级热处理及精密矫正等九道工序,实现工艺革新。经正交试验与试产验证:产品尺寸公差控制在±0.02mm内,生产效率提升超过15%,不良率降至0.3%以下,力学性能与一致性显著提高。该方案已申请发明专利,为规模化高精度生产提供了可靠技术路径,具有重要工程推广价值。 展开更多
关键词 精密选针压脚 电脑横机 高效生产 工艺优化 尺寸精度
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COMPUTERIZED SIMULATION AND EXPERIMENTAL RESEARCH ON SOFT-SWITCHING ARC WELDING INVERTER POWER SOURCE 被引量:24
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作者 S. J. Chen S. Y. Yin L. Feng and L. Y. Li( 1) School of Materials Science and Engineering, Beijing Polytechnic University, Beijing 100022, China 2)National Key Laboratory of Advanced Welding Production Technology, HIT, Harbin 150001, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期128-132,共5页
Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic ... Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic capacitance. Using this model, computerized simulation is conducted for the FB - ZVZCS - PWM soft - ewitching converter,the switching and energy-transferring characteristics of the components are analyzed.The simulation results are testified by experiments.It is proved that by abopting appropriate models,computerized simulation becomes an effective tool for investigation of arc welding inverter power source. 展开更多
关键词 arc welding inverter computerized simulation.IGBT soft switching
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Adult reference values of the computerized diplopia test 被引量:8
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作者 Ling-Yun Zhou Tie-Juan Liu Xue-Mei Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第11期1646-1650,共5页
AIM: To estimate the adult reference values for measured deviations by a computerized diplopia test and testify the validity.METHODS: Totally 391 participants were recruited and taken the computerized diplopia test.... AIM: To estimate the adult reference values for measured deviations by a computerized diplopia test and testify the validity.METHODS: Totally 391 participants were recruited and taken the computerized diplopia test. The plots and amplitude of deviations were recorded. The differences in different gender, age and visual acuity groups were analyzed respectively. Of 30 subjects were enrolled to testify the interobserver reliability. Another 46 subjects(including 26 normal subjects and 20 patients) were taken the test and theirs deviations were recorded to testify the validity of the reference value.RESULTS: The max horizontal and vertical deviations were 2.55° and 0.76° with normal corrected visual acuity while 3.88° and 1.46° for subjects with poor corrected vision. The differences between age groups was insignificant(Z =3.615, 4.758; P =0.461, 0.313 for horizontal and vertical respectively). The max horizontal deviation of female was smaller than male(Z =-2.177; P =0.029),but the difference in max vertical deviation was insignificant(Z =-1.296; P =0.195). The mean difference between observers were both-0.1°, with 95% confidence limits(CI) of-1.4° and 1.6° in max horizontal deviations while-2.1° and 1.8° in max vertical deviation. The mean deviation of 26 normal subjects was 1.02° ±0.84° for horizontal and 0.47° ±0.30° for vertical which both within the range of reference values. The mean deviation of 20 patients was 13.51°±11.69° for horizontal and 8.34°±8.58°for vertical which both beyond the reference range.CONCLUSION: The max amplitude of horizontal and vertical deviation is pointed as the numerical parameters of computerized diplopia test. The reference values are different between normal corrected visual acuity and poor corrected vision. These values may useful for evaluating patients with diplopia in veriety conditions during clinical practice. 展开更多
关键词 computerized diplopia test referencevalues amplitude of deviations
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Identification of Porphyra lines using computerized DNA fingerprinting 被引量:7
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作者 WangBin, Jia Jianhang, Shi Jinfeng, Chen Yihua, JinDemin, Xu Pu, Mei Junxue, Weng Manli 1. Institute of Genetics, Chinese Academy of Sciences, Beijing 100101 (E-mail: mlweng@genetics. ac. cn), China 2. Jiangsu Marine Fishery Institute, Nan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第3期401-407,共7页
RAPD (Randomly Amplified Polymorphic DNA) analysis was performed with filaments of 15 Porphyra lines representing four important groups (P. yezoensis, P. haitanensis, P. katadai var. Hemiphylla and P. digospermatangia... RAPD (Randomly Amplified Polymorphic DNA) analysis was performed with filaments of 15 Porphyra lines representing four important groups (P. yezoensis, P. haitanensis, P. katadai var. Hemiphylla and P. digospermatangia). Eight stable and repeatable RAPD bands amplified with two primers, OPN-02 and OPJ-18, were selected for the construction of DNA fingerprinting. The RAPD results were scored based on the presence or absence of each of the 8 bands and then converted to computer language expressed with two digitals, 1 and 0, which represented the presence (numbered as 1) or absence (numbered as 0) of each band, respectively. Based on these results, a model DNA fingerprint and a computerized DNA fingerprint were constructed. In the constructed DNA fingerprint, each Porphyra line has its unique fingerprinting pattern and can be easily distinguished from each other. Later, a software, named as PhGI, was designed based on this DNA fingerprinting. It can be used in practical Porphyra line identification. 展开更多
关键词 computerized DNA fingerprinting RAPD Porphyra germplasm identification
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Peripancreatic collections in acute pancreatitis: Correlation between computerized tomography and operative fi ndings 被引量:5
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作者 Santhi Swaroop Vege Joel G Fletcher +1 位作者 Rupjyoti Talukdar Michael G Sarr 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第34期4291-4296,共6页
AIM: To evaluate the ability of contrast-enhanced computerized tomography (CECT) to characterize the nature of peripancreatic collections.METHODS: Twenty five patients with peripancreatic collections on CECT and who u... AIM: To evaluate the ability of contrast-enhanced computerized tomography (CECT) to characterize the nature of peripancreatic collections.METHODS: Twenty five patients with peripancreatic collections on CECT and who underwent operative intervention for severe acute pancreatitis were retrospectively studied. The collections were classified into (1) necrosis without frank pus; (2) necrosis with pus; and (3) fluid without necrosis. A blinded radiologist assessed the preoperative CTs of each patient for necrosis and peripancreatic fluid collections. Peripancreatic collections were described in terms of volume, location, number, heterogeneity, fluid attenuation, wall perceptibility, wall enhancement, presence of extraluminal gas, and vascular compromise.RESULTS: Fifty-four collections were identif ied at operation, of which 45 (83%) were identif ied on CECT. Of these, 25/26 (96%) had necrosis without pus, 16/19 (84%) had necrosis with pus, and 4/9 (44%) had fluid without necrosis. Among the study characteristics, fluid heterogeneity was seen in a greater proportion of collections in the group with necrosis and pus, compared to the other two groups (94% vs 48% and 25%, P = 0.002 and 0.003, respectively). Among the wall characteristics, irregularity was seen in a greater proportion of collections in the groups with necrosis with and without pus, when compared to the group with fluid without necrosis (88% and 71% vs 25%, P = 0.06 and P < 0.01, respectively). The combination of heterogeneity and presence of extraluminal gas had a specif icity and positive likelihood ratio of 92% and 5.9, respectively, in detecting pus. CONCLUSION: Most of the peripancreatic collections seen on CECT in patients with severe acute pancreatitis who require operative intervention contain necrotic tissue. CECT has a somewhat limited role in differentiating the different types of collections. 展开更多
关键词 Contrastenhanced computerized tomogra-phy CORRELATION Pancreatic necrosis PANCREATITIS Peripancreatic fluid collection Surgery
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Positron emission tomography/computerized tomography in the evaluation of primary non-Hodgkin's lymphoma of prostate 被引量:4
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作者 Bo Pan Jian-Kui Han +1 位作者 Shi-Cun Wang Ao Xu 《World Journal of Gastroenterology》 SCIE CAS 2013年第39期6699-6702,共4页
Primary malignant lymphoma of the prostate is exceedingly rare.Here we report a case of a 65-year-old man who presented with increased urinary frequency,urinary urgency,and urinary incontinence for two years.Benign pr... Primary malignant lymphoma of the prostate is exceedingly rare.Here we report a case of a 65-year-old man who presented with increased urinary frequency,urinary urgency,and urinary incontinence for two years.Benign prostatic hypertrophy was suspected at primary impression.Ultrasound revealed a hypoechoic lesion of the prostate.The total serum prostate-specific antigen was within normal range.Positron emission tomography/computerized tomography(PET/CT)showed a hypermetabolic prostatic lesion.Prostate biopsy was consistent with a non-germinal center diffuse large B cell lymphoma.There was complete remission of the prostatic lesion following six cycles of chemotherapy as shown on the second PET/CT imaging.18F-fluoro-deoxy glucose PET/CT is not only a complement to conventional imaging,but also plays a significant role in the diagnosis and evaluation of treatment response of prostatic lymphoma. 展开更多
关键词 Fluoro-Deoxy-Glucose Positron emission tomography/computerized tomography Non-Hodgkin’s LYMPHOMA PROSTATIC LYMPHOMA EVALUATION
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Application of Proton Magnetic Resonance Spectroscopy and Computerized Tomography in the Diagnosis and Treatment of Nonalcoholic Fatty Liver Disease 被引量:4
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作者 王南 董慧 +1 位作者 魏世超 陆付耳 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第3期295-298,共4页
In order to investigate the application of proton magnetic resonance spectroscopy (ill-MRS) and computerized tomography (CT) in the quantitative diagnosis of nonalcoholic fatty liver disease (NAFLD) and evaluati... In order to investigate the application of proton magnetic resonance spectroscopy (ill-MRS) and computerized tomography (CT) in the quantitative diagnosis of nonalcoholic fatty liver disease (NAFLD) and evaluation of therapeutic effects, 22 patients with NAFLD were selected according to the Chinese Medical Association's (CMA) standard of the NAFLD in comparison with 20 healthy volunteers (as control group). Blood samples for biochemistry were collected. The severity of hepatosteatosis was evaluated by ^1H-MRS scan and CT scan of liver. The intrahepatic content of lipid (IHCL) and CT value ratio of liver to spleen were calculated. The patients in NAFLD group were treated with Ganzhixiao Capsule for 8 weeks. The changes in IHCL and CT value ratio of liver to spleen were observed before and after treatment. In NAFLD group serum ALT, TG, IHCL calculated by ^1HMRS were increased and CT value ratio of liver to spleen decreased significantly as compared with control group. After treatment for 8 weeks serum ALT, TG, IHCL were decreased significantly, while CT value ratio of liver to spleen increased significantly in NAFLD group. It was suggested that IHCL could be measured precisely by ^1HMRS. NAFLD was treated effectively by Ganzhixiao capsule. 展开更多
关键词 proton magnetic resonance spectroscopy computerized tomography nonalcoholic fatty liver disease
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COMPUTERIZED SIMULATION OF MOLTEN SALT SOLUTION OF Li,KF,Cl SYSTEM BY MOLECULAR DYNAMIC METHOD 被引量:2
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作者 SHAO Jun Shanghai University of Science and Technology,Shanghai,ChinaXU Hua CHEN Nianyi Shanghai Institute of Metallurgy,Academia Sinica,Shanghai,China SHAO Jun Associate Professor,Dept.of Chemistry,Shanghai University of Science and Technology,Shanghai 201800,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1990年第10期221-225,共5页
The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusio... The structure and properties of molten salt solution o J Li,K|F,Cl system have been investiged by computerized simulation of molecular dynamic method.The partial RDF,the partial molar energy of mixing and the diffusion coeffients of Li^+,K^+,F^- and Cl^- have been calculated. The results are in agreement with the experimental values.The regularities of the distribution of ions and mieroscopic holes are discussed based on the results of computerized simulation. 展开更多
关键词 alkali halide molten salt molecular dynamic method computerized simulation
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The Clinical Application of Computerized Three-Dimensional Mimic Operation for Maxillofacial Bone Tumor 被引量:2
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作者 陶学金 殷孝蓉 +1 位作者 朱芳 陈卫民 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1999年第4期328-330,共3页
Facial bone, as the frame to support maxillofacial region and with several sinuses and cavities, is structurally complicated and the maxillofacial tumors,benign or malignant, in this region usually grows into the deep... Facial bone, as the frame to support maxillofacial region and with several sinuses and cavities, is structurally complicated and the maxillofacial tumors,benign or malignant, in this region usually grows into the deep tissues, sinus-cav-ities and orbit and destroys the bone. In this study, the maxillofacial tumors were subjected to a mimic operation on a computer following CT scanning and 3-dimen-sional reconstruction. The data similar to those of real operation were obtained,which could be used for developing operative plans. As compared with data on the basis of conditions in the real operation, computerized mimic operation reflected the real conditions during operation. Computerized mimic operation is valuable for the preoperative planning and the prediction of probable intraoperative events. 展开更多
关键词 maxillofacia tumor computerized mimic operation computed tomography
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Applied Strain Field on Microstructure Optimization of Ti-Al-Nb Alloy Computer Simulated by Phase Field Approach 被引量:3
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作者 Wei GUO Yaping ZONG +1 位作者 Gang WANG Liang ZUO Department of Materials Science and Engineeing,Northeastern University,Shenyang 110004, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第3期245-248,共4页
The effects of applied tensile strain on the coherent α_2→O-phase transformation in Ti-Al-Nb alloys are explored bycomputer simulation using a phase-field method. The focus is on the influence of the applied strain ... The effects of applied tensile strain on the coherent α_2→O-phase transformation in Ti-Al-Nb alloys are explored bycomputer simulation using a phase-field method. The focus is on the influence of the applied strain direction onthe microstructure and volume fraction of the O-phase precipitates. It is found that altering applied strain directioncan modify microstructure of Ti-25Al-10~12Nb (at. pct) alloy during α_2→O-phase transformation effectively andfull laminate microstructure in the Ti-25Al-10Nb (at. pct) alloy can be realized by an applied strain only along thedirection 30°away from the α_2 phase <1010> in magnitude equivalent to the stress-free transformation strain. Thesimulation also shows that not only the magnitude of applied strain but also the applied strain direction influencesthe O-phase volume fraction and the effect of strain direction on the volume fraction is up to 25%. 展开更多
关键词 Phase field simulation Strain induced phase transformation Ti-Al-Nb alloy computerization materials Microstructure evoutionv Precipitates geometry Microstructure design
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Effects of Irregular Respiratory Motion on the Positioning Accuracy of Moving Target with Free Breathing Cone-Beam Computerized Tomography 被引量:1
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作者 Xiang Li Tianfang Li +9 位作者 Ellen Yorke Gig Mageras Xiaoli Tang Maria Chan Weijun Xiong Marsha Reyngold Richard Gewanter Abraham Wu John Cuaron Margie Hunt 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第2期173-183,共11页
For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT ... For positioning a moving target, a maximum intensity projection (MIP) or average intensity projection (AIP) image derived from 4DCT is often used as the reference image which is matched to free breathing cone-beam CT (FBCBCT) before treatment. This method can be highly accurate if the respiratory motion of the patient is stable. However, a patient’s breathing pattern is often irregular. The purpose of this study is to investigate the effects of irregular respiration on positioning accuracy for a moving target aligned with FBCBCT. Nine patients’ respiratory motion curves were selected to drive a Quasar motion phantom with one embedded cubic and two spherical targets. A 4DCT of the phantom was acquired on a CT scanner (Philips Brilliance 16) equipped with a Varian RPM system. The phase binned 4DCT images and the corresponding MIP and AIP images were transferred into Eclipse for analysis. FBCBCTs of the phantom driven by the same respiratory curves were also acquired on a Varian TrueBeam and fused such that both CBCT and MIP/AIP images share the same target zero positions. The sphere and cube volumes and centroid differences (alignment error) determined by MIP, AIP and FBCBCT images were calculated, respectively. Compared to the volume determined by MIP, the volumes of the cube, large sphere, and small sphere in AIP and FBCBCT images were smaller. The alignment errors for the cube, large sphere and small sphere with center to center matches between MIP and FBCBCT were 2.5 ± 1.8 mm, 2.4 ± 2.1 mm, and 3.8 ± 2.8 mm, and the alignment errors between AIP and FBCBCT were 0.5 ± 1.1 mm, 0.3 ± 0.8 mm, and 1.8 ± 2.0 mm, respectively. AIP images appear to be superior reference images to MIP images. However, irregular respiratory pattern could compromise the positioning accuracy, especially for smaller targets. 展开更多
关键词 CONE Beam computerIZED TOMOGRAPHY RESPIRATORY Motion Effect
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Recent Progress in Computerization of TCM 被引量:1
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作者 Zhi Liu Jingqi Yan +1 位作者 Qunlin Tang Qingli Li 《通讯和计算机(中英文版)》 2006年第7期78-81,共4页
关键词 终端设备至计算机多路转接器 生物工程 计算机化 计算机技术
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AN ANALYSIS OF ACOUSTIC CHARACTERISTICS OFCLEFT PALATE SPEECH WITH COMPUTERIZED SPEECH SIGNAL PROCESSING SYSTEM 被引量:1
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作者 李锦峰 刘建华 《Journal of Pharmaceutical Analysis》 CAS 1996年第2期162-165,共4页
The acoustic characteristics or the chinese vowels of 24 children with cleft palate and 10 normal control children were analyzed by computerized speech signal processing system (CSSPS),and the speech articulation was ... The acoustic characteristics or the chinese vowels of 24 children with cleft palate and 10 normal control children were analyzed by computerized speech signal processing system (CSSPS),and the speech articulation was judged with Glossary of clert palate speech(GCPS).The listening judgement showed that the speech articulation was significantly different between the two groups(P<0.01).The objective quantitative measurement suggested that the formant pattern(FP)of vowels in children with cleft palate was different from that of normal control children except vowel[a](P< 0.05).The acoustic vowelgraph or the Chinese vowels which demonstrated directly the relationship of vocal space and speech perception was stated with the first formant frequence(F1)and the second formant frequence(F2).The authors conclude that the values or F1 and F2 point out the upward and backward tongue movement to close the clert, which reflects the vocal characteristics of trausmission of clert palate speech. 展开更多
关键词 cleft palate speech the Chinese vowels the formant pattern the speech articulation computerized speech singnal processing system
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Changes in reaction time, coefficient of variance of reaction time, and autonomic nerve function in the mental fatigue state caused by long-term computerized Kraepelin test workload in healthy volunteers 被引量:1
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作者 Daisuke Kuratsune Seiki Tajima +10 位作者 Junichi Koizumi Kouzi Yamaguti Tetsuya Sasabe Kei Mizuno Masaaki Tanaka Naoko Okawa Hideki Mito Hirokazu Tsubone Yasuyoshi Watanabe Masayasu Inoue Hirohiko Kuratsune 《World Journal of Neuroscience》 2012年第2期113-118,共6页
Fatigue is a common sense caused by crushing labor, stressful social events and various illnesses. It is usually judged by their subjective symptoms, but it should be evaluated in an objective perspective. Here we sho... Fatigue is a common sense caused by crushing labor, stressful social events and various illnesses. It is usually judged by their subjective symptoms, but it should be evaluated in an objective perspective. Here we show that the decrease of working efficiency and sympathetic hyperactivity are associated with mental fatigue state caused by prolonged mental workload. Recently we made a new mental fatigue model of healthy volunteers caused by long-term computerized Kraepelin test (CKT) workload. CKT is our new software for automatically checking the calculation capability, with which it is easy to determine the reaction time (RT), coefficient of variance of reaction time (CV), and accuracy of the answers (AC) during tasks. We put 24 healthy volunteers into the fatigue state by subjecting them to 120 minutes’ CKT workload, and then studied the changes in fatigue sensation, RT, CV, and AC before and after the CKT workload. The fatigue sensation, RT, and CV were clearly increased by the fatigue-inducing task and recovered during the resting period. We also studied the changes in autonomic nerve activity by using heart rate variability analysis. The low/high frequency component ratio (LF/HF) was signifi-cantly increased by the fatigue-inducing task and decreased by resting, suggesting that mental stress causes a relatively sympathetic nerve activity-dominant state. Therefore, our new fatigue model involving a long-term CKT workload is a good mental fatigue model to provide much information about the fatigue state simultane-ously, and the increase of RT, CV, and proportion of sympathetic activity (LF/HF) are associated with mental fatigue state. These might be useful objective biomarkers or evaluating a mental fatigue state. 展开更多
关键词 Fatigue computerIZED Kraepelin Test Reaction Time Accuracy of the ANSWERS AUTONOMIC NERVE Activity
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