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ChatGPT可否充当情感专家?——调查其在情感与隐喻分析的潜力
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作者 张亚洲 王梦遥 +3 位作者 戎璐 俞洋 赵东明 秦璟 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期43-52,共10页
为了探索ChatGPT情感分析能力以及对主观性和隐喻性理解的潜力,将ChatGPT在5个情感、幽默与隐喻基准数据集上展开评估,通过与领域内最前沿的模型对比,讨论其在不同任务上的优势与局限。此外,还通过对比ChatGPT与人类在情感分析中的性能... 为了探索ChatGPT情感分析能力以及对主观性和隐喻性理解的潜力,将ChatGPT在5个情感、幽默与隐喻基准数据集上展开评估,通过与领域内最前沿的模型对比,讨论其在不同任务上的优势与局限。此外,还通过对比ChatGPT与人类在情感分析中的性能差别,发现ChatGPT在情感、幽默与隐喻任务上与人类结果分别相差9.52%,16.64%和6.69%。实验结果表明,尽管ChatGPT在对话生成方面获得最佳表现,但是其在情感理解方面仍具有改进的潜力。最后,通过改善提示模板,调查ChatGPT在情感理解场景下对提示模板的敏感性。 展开更多
关键词 ChatGPT 情感分析 幽默检测 隐喻识别
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PhaseⅠ/Ⅱtrial evaluating concurrent carbon-ion radiotherapy plus chemotherapy for salvage treatment of locally recurrent nasopharyngeal carcinoma 被引量:8
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作者 Lin Kong Jing Gao +4 位作者 Jiyi Hu Weixu Hu Xiyin Guan rong lu Jiade J.lu 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第12期743-753,共11页
Background: After deinitive chemoradiotherapy for non-metastatic nasopharyngeal carcinoma(NPC), more than 10% of patients will experience a local recurrence. Salvage treatments present signiicant challenges for locall... Background: After deinitive chemoradiotherapy for non-metastatic nasopharyngeal carcinoma(NPC), more than 10% of patients will experience a local recurrence. Salvage treatments present signiicant challenges for locally recurrent NPC. Surgery, stereotactic ablative body radiotherapy, and brachytherapy have been used to treat locally recurrent NPC. However, only patients with small-volume tumors can beneit from these treatments. Re-irradiation with X-ray—based intensity-modulated radiotherapy(IMXT) has been more widely used for salvage treatment of locally recurrent NPC with a large tumor burden, but over-irradiation to the surrounding normal tissues has been shown to cause frequent and severe toxicities. Furthermore, locally recurrent NPC represents a clinical entity that is more radioresistant than its primary counterpart. Due to the inherent physical advantages of heavy-particle therapy, precise dose delivery to the target volume(s), without exposing the surrounding organs at risk to extra doses, is highly feasible with carbon-ion radiotherapy(CIRT). In addition, CIRT is a high linear energy transfer(LET) radiation and provides an increased relative biological efectiveness compared with photon and proton radiotherapy. Our prior work showed that CIRT alone to 57.5 Gy E(gray equivalent), at 2.5 Gy E per daily fraction, was well tolerated in patients who were previously treated for NPC with a deinitive dose of IMXT. The short-term response rates at 3–6 months were also acceptable. However, no patients were treated with concurrent chemotherapy. Whether the addition of concurrent chemotherapy to CIRT can beneit locally recurrent NPC patients over CIRT alone has never been addressed. It is possible that the beneits of high-LET CIRT may make radiosensitizing chemotherapy unnecessary. We therefore implemented a phase I/II clinical trial to address these questions and present our methodology and results.Methods and design: The maximal tolerated dose(MTD) of re-treatment using raster-scanning CIRT plus concurrent cisplatin will be determined in the phase I, dose-escalating stage of this study. CIRT dose escalation from 52.5 to 65 Gy E(2.5 Gy E × 21–26 fractions) will be delivered, with the primary endpoints being acute and subacute toxicities. Eicacy in terms of overall survival(OS) and local progression-free survival of patients after concurrent chemotherapy plus CIRT at the determined MTD will then be studied in the phase II stage of the trial. We hypothesize that CIRT plus chemotherapy can improve the 2-year OS rate from the historical 50% to at least 70%.Conclusions: Re-treatment of locally recurrent NPC using photon radiation techniques, including IMXT, provides moderate eicacy but causes potentially severe toxicities. Improved outcomes in terms of eicacy and toxicity proile are expected with CIRT plus chemotherapy. However, the MTD of CIRT used concurrently with cisplatin-based chemotherapy for locally recurrent NPC remains to be determined. In addition, whether the addition of chemotherapy to CIRT is needed remains unknown. These questions will be evaluated in the dose-escalating phase I and randomized phase II trials. 展开更多
关键词 Recurrent nasopharyngeal cancer Carbon ion radiotherapy RE-IRRADIATION Salvage therapy CHEMOTHERAPY
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The inflammation influence on corneal surface after frontalis suspension surgery 被引量:2
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作者 Kang Li Xin-Chun Zhang +2 位作者 Xian-Xian Cai Ya-Dan Quan rong lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第9期1489-1495,共7页
AIM: To study the influence of frontalis muscle flap suspension on ocular surface by analyzing the clinical features and inflammatory cytokines.METHODS: A prospective, observational case series. Thirty-one eyes of 25 ... AIM: To study the influence of frontalis muscle flap suspension on ocular surface by analyzing the clinical features and inflammatory cytokines.METHODS: A prospective, observational case series. Thirty-one eyes of 25 patients with severe congenital blepharoptosis who underwent frontalis muscle flap suspension surgery with at least 6 mo of follow-up were included in the study. The main outcome measures were margin reflex distance 1(MRD_1), degree of lagophthalmos, ocular surface disease index(OSDI), fluorescein staining(Fl), tear break-up time(BUT), Schirmer I test, and inflammatory cytokine assay.RESULTS: The degrees of lagophthalmos significantly increased after surgery. The OSDI scores significantly increased 1wk postoperatively and then decreased 4wk after operation. The Fl scores reflected corneal epithelial defects in sixteen patients at early stage postoperatively. The BUT and Schirmer I test values remained stable and did not show change compared to those before surgery. The inflammatory cytokines in conjunctival epithelial cells(including IL-1β, IL-6, IL-8, TNF-α, and IL-17A) significantly increased 1wk after the surgery(P<0.001), then returned to the normal level at 24wk postoperatively. The levels of inflammatory cytokine IL-1β, IL-6, IL-8, TNF-α, and IL-17A elevated significantly and were positively correlated with OSDI and Fl scores.CONCLUSION: Frontalis muscle flap suspension surgery results in lagophthalmos in early period of post-operation and relieved after months. The elevation of inflammatory cytokines level may participate in the occurrence of corneal epithelial defects at the early postoperative stage. 展开更多
关键词 congenital blepharoptosis frontalis muscle flap suspension corneal epithelial defects INFLAMMATION
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Value of gastroscopy combined with serum pepsinogen in the diagnosis of high risk Hp related gastric cancer 被引量:1
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作者 Lin Liu rong lu +1 位作者 Ying Chen Wen-Tao Guo 《Journal of Hainan Medical University》 2018年第2期44-46,共3页
Objective:To explore the value of Helicobacter pylori antibody (Hp-IgG) and serum pepsinogen (PG) combined with gastroscopy for screening early gastric cancer and precancerous lesions in high-risk groups, so as to pro... Objective:To explore the value of Helicobacter pylori antibody (Hp-IgG) and serum pepsinogen (PG) combined with gastroscopy for screening early gastric cancer and precancerous lesions in high-risk groups, so as to provide references for early clinical prevention and diagnosis.Methods: A retrospective analysis of our hospital from December 2014 to December 2017 were elderly patients with gastric cancer 304 cases, selected admitted 122 cases of elderly patients with gastric precancerous lesion (divided into superficial gastritis group, 70 cases of chronic atrophic gastritis group 52 cases) and 156 cases to the hospital in healthy volunteers as the control group. The status and the positive rate of Helicobacter pylori 13C urea breath test and compared two groups of patients with infection;using enzyme-linked immunosorbent assay of serum pepsinogen I (PG I), II (PG II) and pepsin Hp-IgG quantitative and qualitative diagnosis of individual and combined diagnostic efficiency and the comparison of three kinds of index.Results: The four groups were compared, the serum PG level of I from high to low were superficial gastritis group, normal control group, atrophic gastritis group and gastric cancer group, the differences were statistically significant;serum PG II levels from high to low in gastric cancer group and superficial gastritis group. Atrophic gastritis group, normal control group, the differences were statistically significant. Compared with the three groups, the positive rate of Hp-IgG was 90.7% in the gastric cancer group, 45.6% in the superficial gastritis group, 52.5% in the atrophic gastritis group, and the gastric cancer group was higher than that in the precancerous lesion group, but there was no difference between the precancerous lesions group. In terms of diagnostic efficacy, the specificity and sensitivity of Helicobacter pylori combined with pepsinogen were higher than those of the single diagnosis. Conclusion: Hp-IgG and PG combined with gastroscopy in screening high-risk gastric cancer and its precancerous lesions are of high specificity, high sensitivity and can be popularized in clinic. 展开更多
关键词 HELICOBACTER pylori PEPSINOGEN High risk HP RELATED gastric cancer GASTROSCOPE
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Successful treatment of Morbihan disease with total glucosides of paeony:A case report
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作者 Li-Feng Zhou rong lu 《World Journal of Clinical Cases》 SCIE 2022年第19期6688-6694,共7页
BACKGROUND Morbihan disease is a rare cutaneous disorder characterized by non-pitting edema and erythema of the upper two-thirds of the face.In severe cases,orbital and facial contour changes may affect the visual fie... BACKGROUND Morbihan disease is a rare cutaneous disorder characterized by non-pitting edema and erythema of the upper two-thirds of the face.In severe cases,orbital and facial contour changes may affect the visual field,and there is no guideline for the standard treatment of this disease.Existing treatment methods have been reported to be associated with long medication cycle,easy recurrence after drug withdrawal,and multiple adverse reactions.CASE SUMMARY A 55-year-old Chinese woman presented to our hospital with non-pitting edema and erythema of the upper two thirds of her face for 5 mo.Physical examination showed obvious edema and erythema on the upper face.The boundary was unclear,the lesions were hard and non-pitting,and infiltration was obvious by touch.Pathological examination revealed mild hyperkeratosis of the epidermis,nodular inflammatory lesions in the dermis,epithelioid granuloma,and inflammatory cell infiltration with lymphocytes and histiocytes around skin appendages and blood vessels.Alcian blue staining,acid fast staining,silver staining and periodic acid-Schiff staining were negative.The patient was diagnosed with Morbihan disease.She was treated with prednisone acetate and tripterygium wilfordii polyglycoside tablets for 4 mo,and the edema was slightly reduced,but transaminase levels were significantly increased.Compound glycyrrhizin capsules were administered for liver protection for 1 mo;however,facial edema did not significantly improve and transaminase levels continued to increase.Total glucosides of paeony capsules were then administered for 4 mo,and transaminase level returned to normal and the patient’s facial edema disappeared completely.CONCLUSION Total glucosides of paeony has a remarkable effect in Morbihan disease,without adverse reactions. 展开更多
关键词 Morbihan disease Morbihan syndrome Total glucosides of paeony Prednisone acetate Tripterygium wilfordii Case report
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Effects of nutritional support and intervention on intestinal flora, Th cellular immune response and inflammatory response in patients with severe ulcerative colitis
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作者 Hong-Fen Fan rong lu 《Journal of Hainan Medical University》 2017年第23期37-40,共4页
Objective: To explore the effects of nutritional support and intervention on intestinal flora, Th cellular immune response and inflammatory response in patients with severe ulcerative colitis. Methods: A total of 90 U... Objective: To explore the effects of nutritional support and intervention on intestinal flora, Th cellular immune response and inflammatory response in patients with severe ulcerative colitis. Methods: A total of 90 UC patients who were diagnosed and treated in the hospital between August 2014 and January 2017 were divided into the control group (n=45) and the nutritional intervention group (n=45) by random number table. Control group received clinical routine therapy for UC, and nutritional intervention group received routine therapy as well as nutritional support and intervention. The differences in the intestinal flora distribution, Th1/Th2 cytokine contents and inflammatory mediator contents were compared between the two groups. Results: Before intervention, there was no statistically significant difference in the intestinal flora distribution, Th1/Th2 cytokine contents and inflammatory mediator contents between the two groups. After intervention, the number of enterobacter and enterococcus in nutritional intervention group were lower than those in control group whereas the number of lactobacilli, Bifidobacterium and clostridium butyricum were higher than those in control group;serum IL-2 and IFN-γ contents were lower than those of control group whereas IL-4 and IL-10 contents were higher than those of control group;serum MCP-1, MIP-1a and HMGB-1 contents were lower than those of control group. Conclusion: Nutritional support and intervention can further balance the intestinal flora distribution and Th1/Th2 immune response and suppress the systemic inflammatory response in patients with severe ulcerative colitis. 展开更多
关键词 SEVERE ULCERATIVE colitis NUTRITIONAL support Intestinal FLORA TH cellular immune RESPONSE Inflammatory RESPONSE
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超声造影参数联合血清FGF23和FGFR1水平检测对乳腺癌的临床诊断价值研究
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作者 荣鹿 周敏 +2 位作者 于鲁欣 吕娟 万静 《现代检验医学杂志》 CAS 2023年第5期185-189,共5页
目的 探讨超声造影参数联合血清成纤维细胞生长因子-23(fibroblast growth factor-23,FGF23)和成纤维细胞生长因子受体1(fibroblast growth factor receptor 1,FGFR1)在诊断乳腺癌的临床应用价值。方法 选择2020年8月~2022年6月在新疆... 目的 探讨超声造影参数联合血清成纤维细胞生长因子-23(fibroblast growth factor-23,FGF23)和成纤维细胞生长因子受体1(fibroblast growth factor receptor 1,FGFR1)在诊断乳腺癌的临床应用价值。方法 选择2020年8月~2022年6月在新疆维吾尔自治区人民医院就诊的87例乳腺癌患者作为观察对象(恶性组),选取同期90例乳腺良性病变患者作为良性组,分析两组观察对象超声造影参数,酶联免疫吸附法(enzyme-linked immunosorbent assay,ELISA)检测血清FGF23和FGFR1表达水平,Pearson法分析乳腺癌患者血清FGF23和FGFR1水平与超声造影参数的相关性,ROC曲线分析超声造影参数、血清FGF23和FGFR1对乳腺癌的诊断价值。结果 与良性组比较,恶性组的超声造影峰值强度(peak intensity,PI)(15.36±3.47 dB vs 12.54±2.83 dB)、曲线下面积(area under curve,AUC)(382.69±90.51 dB/s vs 262.95±75.34 dB/s)及血清FGF23(119.28±26.41 pg/ml vs 86.41±20.35 pg/ml),FGFR1(11.36±3.42 ng/mL vs 7.24±2.26 ng/mL)水平升高,达峰时间(time to peak,TTP)(18.46±4.31 s vs 24.23±5.25 s)降低,差异均有统计学意义(t=5.934~9.579,均P=0.000)。相关性分析显示,乳腺癌患者血清FGF23水平与PI,AUC呈正相关(r=0.493,0.561,均P=0.000),与TTP呈负相关(r=-0.572,P=0.000);血清FGFR1水平与PI,AUC呈正相关(r=0.603,0.491,均P=0.000),与TTP呈负相关(r=-0.545,P=0.000)。超声造影参数联合血清FGF23和FGFR1诊断乳腺癌的曲线下面积为0.971,联合诊断效能明显高于单独诊断,差异均有统计学意义(Z=6.478,5.558,4.839,4.780,4.943,均P <0.05)。结论 超声造影参数联合血清FGF23和FGFR1对乳腺癌具有较高诊断价值,可为乳腺癌的临床诊治提供参考。 展开更多
关键词 超声造影 成纤维细胞生长因子-23 成纤维细胞生长因子受体1 乳腺癌
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丁羟推进剂药浆流平性能实验与模拟
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作者 周君 李卓 +2 位作者 鲁荣 魏凌云 张芙宁 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2023年第4期85-92,共8页
为研究表观黏度及屈服应力对丁羟推进剂药浆流平性的影响,文中对丁羟推进剂药浆进行了流平性实验,并提出滞止角的概念来表征药浆的流平性,得出药浆屈服应力对滞止角的影响规律。同时采用Carreau黏度模型模拟了药浆流平过程并与实验结果... 为研究表观黏度及屈服应力对丁羟推进剂药浆流平性的影响,文中对丁羟推进剂药浆进行了流平性实验,并提出滞止角的概念来表征药浆的流平性,得出药浆屈服应力对滞止角的影响规律。同时采用Carreau黏度模型模拟了药浆流平过程并与实验结果进行了对比,并通过计算软件Flow3D定量表征了丁羟推进剂药浆的表观黏度、屈服应力单变量对流平性的影响。结果表明,丁羟推进剂药浆的流动角度与药浆流平时间的对数满足线性关系;不同时刻药浆流动角度的数值模拟与实验结果误差在5%以内,内侧流到终点的时间相差小于10%,验证了Carreau黏度模型求解药浆流平过程的可行性。丁羟推进剂药浆的表观黏度是影响流平速度的主要参数,当表观黏度由400 Pa·s增大到1000 Pa·s时,药浆流平所需时间由277s延长到871s;屈服应力决定了药浆流平结束时滞止角的大小,当屈服应力由60Pa增大到120Pa时,滞止角由8.69°增大到14.98°,相应增加了72.4%。 展开更多
关键词 固体推进剂 药浆 表观黏度 屈服应力 流平性
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基于TPX透镜的连续太赫兹波像面数字全息成像研究 被引量:2
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作者 王云新 朱江磊 +3 位作者 赵洁 王大勇 戎路 林述锋 《光子学报》 EI CAS CSCD 北大核心 2022年第4期108-115,共8页
太赫兹波对非极性材料具有良好的穿透性,与太赫兹波强度成像相比,相衬成像能够更好的反映物体的内部结构。本文提出了基于TPX透镜的连续太赫兹波像面数字全息相衬成像方法,研究了全息记录和再现过程,利用曲面拟合畸变校正去除TPX透镜引... 太赫兹波对非极性材料具有良好的穿透性,与太赫兹波强度成像相比,相衬成像能够更好的反映物体的内部结构。本文提出了基于TPX透镜的连续太赫兹波像面数字全息相衬成像方法,研究了全息记录和再现过程,利用曲面拟合畸变校正去除TPX透镜引入的二次相位畸变。实验搭建了太赫兹像面数字全息成像系统,利用振幅型西门子星样品对系统的成像分辨率进行了定量分析,同时对有机材料和生物样品两种相位型样品进行成像,实验验证了该相衬成像方法的有效性。在太赫兹波段引入像面成像,有利于提高太赫兹成像分辨率及成像质量,在生物医学成像、无损检测等领域具有广泛的应用前景。 展开更多
关键词 太赫兹成像 数字全息 离轴数字全息 像面数字全息 畸变校正
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连续太赫兹波双物距叠层定量相衬成像 被引量:1
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作者 王大勇 李兵 +3 位作者 戎路 赵洁 王云新 翟长超 《物理学报》 SCIE EI CAS CSCD 北大核心 2020年第2期292-301,共10页
针对连续太赫兹波叠层成像重建算法收敛较为迟滞的问题,提出一种连续太赫兹波双物距叠层成像方法及相关重建算法,使用不同记录距离形成的差异化衍射图幅值作为重建算法记录平面的约束条件,增加了记录平面数据多样性和衍射信息冗余度.仿... 针对连续太赫兹波叠层成像重建算法收敛较为迟滞的问题,提出一种连续太赫兹波双物距叠层成像方法及相关重建算法,使用不同记录距离形成的差异化衍射图幅值作为重建算法记录平面的约束条件,增加了记录平面数据多样性和衍射信息冗余度.仿真结果表明,本方法可以加快算法收敛速率,有效减少迭代次数,提高连续太赫兹波定量相衬成像计算效率.随后构建了基于2.52 THz光泵连续太赫兹激光器的双物距叠层成像实验装置,应用双物距记录方法及改进算法重建获得了聚丙烯基字母图案样品的幅值和相位分布,结果表明改进方法可以减少算法迭代次数,提升计算效率,同时改善相位像重建结果保真度. 展开更多
关键词 太赫兹成像 叠层成像 相位复原 双物距
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基于微波频差转换的光学拍频研究 被引量:1
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作者 王云新 王大勇 +3 位作者 杨登才 李平雪 戎路 赵洁 《大学物理》 2021年第3期43-47,共5页
光学拍频是大学物理和光学实验教学中的重要内容.由于激光器存在中心波长漂移问题,实验中不易产生可观测的拍频信号.受到微波光子技术中微波波段和光波波段相互作用机理的启发,提出了基于微波频差转换的光学拍频方法.借助强度调制和相... 光学拍频是大学物理和光学实验教学中的重要内容.由于激光器存在中心波长漂移问题,实验中不易产生可观测的拍频信号.受到微波光子技术中微波波段和光波波段相互作用机理的启发,提出了基于微波频差转换的光学拍频方法.借助强度调制和相位调制将两个频差较小的微波信号调制到同一光载波上,结合光学滤波器获得了两个频差极小的稳定光信号,利用光电探测器实现光学拍频,从仿真和实验两个层面分别获得了可视化的低频拍频信号.该研究为大学物理和光学实验提供了与科学前沿相结合的实验方案,可拓展教学内容和教学深度,有利于培养学生的科学素养. 展开更多
关键词 光学拍频 频率变换 实验教学
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3D打印衍射元件的高分辨太赫兹计算机辅助层析成像研究(特邀)
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作者 王大勇 宁冉 +4 位作者 金晓宇 戎路 赵洁 王云新 林述锋 《光子学报》 EI CAS CSCD 北大核心 2022年第7期107-118,共12页
提出了一种由三维打印技术制作的用于0.3 THz波束调控的二元相位型衍射透镜,可产生轴向焦深为25 mm、腰斑直径为1 mm的太赫兹聚焦波束。将该聚焦波束应用于连续太赫兹波计算机辅助层析成像,不仅将成像分辨率提高到1.5 mm,而且由于扩大... 提出了一种由三维打印技术制作的用于0.3 THz波束调控的二元相位型衍射透镜,可产生轴向焦深为25 mm、腰斑直径为1 mm的太赫兹聚焦波束。将该聚焦波束应用于连续太赫兹波计算机辅助层析成像,不仅将成像分辨率提高到1.5 mm,而且由于扩大了系统景深,提高了成像保真度。这类利用三维打印技术制作的二元衍射元件可有效应用于低频太赫兹波段的光束调控,为太赫兹成像系统的性能优化以及聚焦元件的设计制备提供一种有效途径。 展开更多
关键词 信息光学 太赫兹计算机辅助层析 光束调控 二元衍射透镜 三维打印技术
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角谱法数值再现离轴菲涅耳数字全息成像的物理机制探讨
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作者 赵洁 王大勇 +2 位作者 王云新 戎路 李平雪 《物理与工程》 2021年第4期75-81,共7页
本文以离轴菲涅耳数字全息实验为基础,探讨了基于角谱衍射传播方法进行数字全息图重建的成像性能,重点挖掘数值计算背后的物理机理,帮助学生更好地理解所涉及的信息光学知识点。首先,介绍了离轴菲涅耳数字全息图常用两种再现方法的原理... 本文以离轴菲涅耳数字全息实验为基础,探讨了基于角谱衍射传播方法进行数字全息图重建的成像性能,重点挖掘数值计算背后的物理机理,帮助学生更好地理解所涉及的信息光学知识点。首先,介绍了离轴菲涅耳数字全息图常用两种再现方法的原理,分别是频域滤波方法和空域直接回传方法;然后,利用模拟实验分析了这两种方法在实现成像分辨率和视场方面的特征,把全息理论与仿真现象充分地联系起来,揭示隐藏在数值计算之后的光学原理。本文通过对数字全息图前向和后向传播获取再现像的对比分析,加深对傅里叶变换、衍射传播、频谱滤波等基本物理概念的理解和掌握。 展开更多
关键词 全息成像 数字全息 离轴菲涅耳光路 角谱衍射传播 频谱滤波
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基于电光调制和线性调频去斜的微波光子测距研究
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作者 王云新 姚锦川 +5 位作者 侯雪缘 王大勇 赵洁 杨锋 戎路 林述锋 《物理与工程》 2022年第2期127-132,共6页
传统的电磁测距受到电子学瓶颈的局限,难以进一步提升工作带宽,导致系统的测距精度受限。本文提出了一种基于电光调制和线性调频去斜的微波光子测距方法,利用马赫-曾德尔调制器获取±1阶调制光边带,通过光电探测产生二倍频的宽带线... 传统的电磁测距受到电子学瓶颈的局限,难以进一步提升工作带宽,导致系统的测距精度受限。本文提出了一种基于电光调制和线性调频去斜的微波光子测距方法,利用马赫-曾德尔调制器获取±1阶调制光边带,通过光电探测产生二倍频的宽带线性调频发射信号,可有效提升系统的距离分辨率;在接收端采用线性调频去斜接收的方法,通过探测中频信号的频率反演获得目标距离信息,可极大地降低对后续模数转换器采样速率的要求。该研究将电光调制、光电探测等基础知识实际应用到微波光子测距中,与科学前沿有机结合,有助于拓展教学内容、提升教学深度,有利于培养学生的科学素养和实践能力。 展开更多
关键词 微波光子测距 电光调制 线性调频 光电探测
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基于面阵式探测器连续太赫兹波三维层析成像 被引量:6
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作者 李斌 王大勇 +6 位作者 周逊 戎路 李赜宇 李磊 黄昊翀 万敏 王云新 《太赫兹科学与电子信息学报》 2017年第1期21-25,共5页
太赫兹波层析成像技术是利用太赫兹波的穿透性对样品进行旋转投影数据采集,通过层析重建算法获得样品的二维横截面图,并实现样品的三维内部结构图的重构。本文介绍了基于面阵式探测器连续太赫兹波层析成像系统。该成像系统的优势在于利... 太赫兹波层析成像技术是利用太赫兹波的穿透性对样品进行旋转投影数据采集,通过层析重建算法获得样品的二维横截面图,并实现样品的三维内部结构图的重构。本文介绍了基于面阵式探测器连续太赫兹波层析成像系统。该成像系统的优势在于利用了面阵式探测器记录二维投影数据,相比扫描层析成像系统,提高了投影采集速率。为了获得高精确度的二维投影数据,利用角谱衍射传播算法将二维投影图传播至样品后表面,实现抑制太赫兹波在物体外部衍射效应,最终利用滤波反投影算法重建出高保真的样品三维内部结构图,并进一步探索了基于面阵式探测器的连续太赫兹波层析成像技术在无损检测和安全检测上的可行性。 展开更多
关键词 太赫兹波成像 层析成像 面阵式 三维成像
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连续太赫兹波数字全息相衬成像 被引量:2
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作者 史晓玉 王大勇 +2 位作者 戎路 赵洁 王云新 《光电工程》 CAS CSCD 北大核心 2020年第5期42-54,共13页
太赫兹波具有独特的低能性、高穿透性、惧水性等成像特性,将其应用于相衬成像能够反映物体的内部结构和更加丰富全面的生物信息,在生物医学检测等领域具有重要的应用。其中,太赫兹波数字全息成像是一种可以给出定量的振幅和相位信息的... 太赫兹波具有独特的低能性、高穿透性、惧水性等成像特性,将其应用于相衬成像能够反映物体的内部结构和更加丰富全面的生物信息,在生物医学检测等领域具有重要的应用。其中,太赫兹波数字全息成像是一种可以给出定量的振幅和相位信息的非接触、全场相衬成像方法,是太赫兹成像技术领域的重要研究方向之一。本文基于连续太赫兹源,从离轴式和同轴式数字全息成像的相衬成像原理、光路系统和再现算法多个方面,介绍了相关技术的研究现状,分析了太赫兹源、再现算法等因素对成像分辨率的影响,并对太赫兹数字全息的发展趋势进行了展望。 展开更多
关键词 太赫兹成像 数字全息 分辨率 相衬成像
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连续太赫兹波合成孔径数字全息成像方法 被引量:2
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作者 万敏 黎维华 +4 位作者 王大勇 翟长超 戎路 邓青华 黄昊翀 《太赫兹科学与电子信息学报》 2017年第3期358-363,共6页
太赫兹波数字全息成像技术结合了太赫兹成像技术和数字全息成像技术的优势,是一种新型相衬成像技术,具有光源相干性要求低、光路结构简单、实时定量获取物光波复振幅信息等特点,非常适用于太赫兹波段成像。影响数字全息成像技术分辨力... 太赫兹波数字全息成像技术结合了太赫兹成像技术和数字全息成像技术的优势,是一种新型相衬成像技术,具有光源相干性要求低、光路结构简单、实时定量获取物光波复振幅信息等特点,非常适用于太赫兹波段成像。影响数字全息成像技术分辨力的因素有多种,其中一个主要因素是探测器靶面尺寸的大小,因此,提出合成孔径方法扩大探测器靶面尺寸,提高太赫兹数字全息的成像分辨力。文中搭建了连续太赫兹波同轴数字全息成像装置,获取了样品高质量、高分辨力的振幅和相衬图像。实验结果有效说明了合成孔径方法可以提高太赫兹数字全息成像分辨力。 展开更多
关键词 太赫兹成像 数字全息成像 合成孔径 高分辨力
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多模态情感分析研究综述 被引量:24
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作者 张亚洲 戎璐 +1 位作者 宋大为 张鹏 《模式识别与人工智能》 EI CSCD 北大核心 2020年第5期426-438,共13页
多模态情感分析现已成为自然语言处理领域的核心研究课题之一.文中首先介绍多模态情感分析的研究背景,归纳该领域最新的两类子课题,即叙述式多模态情感分析与交互式多模态情感分析.再分别以这两类子课题为出发点,梳理概括相应的发展脉络... 多模态情感分析现已成为自然语言处理领域的核心研究课题之一.文中首先介绍多模态情感分析的研究背景,归纳该领域最新的两类子课题,即叙述式多模态情感分析与交互式多模态情感分析.再分别以这两类子课题为出发点,梳理概括相应的发展脉络,最后,总结目前该领域中存在的交互建模的科学问题,探讨未来发展方向. 展开更多
关键词 多模态情感分析 情感分类 自然语言处理
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内配格构式钢骨-钢管混凝土构件偏压性能试验研究 被引量:2
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作者 陈庆胜 李博凡 +3 位作者 孔龙 荣鹿 侯新宇 王先铁 《建筑结构》 CSCD 北大核心 2022年第13期77-85,共9页
对4组共8个不同内部构造形式的钢管混凝土试件进行了偏心受压试验。结果表明:各组试件的破坏模式均为试件整体弯曲,偏压侧钢管局部鼓曲。内配纵向加劲肋减缓了钢管的局部鼓曲。与普通钢管混凝土试件相比,内配纵向加劲肋试件的极限承载... 对4组共8个不同内部构造形式的钢管混凝土试件进行了偏心受压试验。结果表明:各组试件的破坏模式均为试件整体弯曲,偏压侧钢管局部鼓曲。内配纵向加劲肋减缓了钢管的局部鼓曲。与普通钢管混凝土试件相比,内配纵向加劲肋试件的极限承载力提高3.80%,内配格构式钢骨试件的极限承载力提高8.28%,同时配置纵向加劲肋和格构式钢骨试件的极限承载力提高14.33%。利用有限元软件对内配格构式钢骨-钢管混凝土构件进行偏心受压数值模拟,分析了构件的受力机理和各部件的应力发展过程,研究了混凝土强度、钢管强度、钢管径厚比、钢骨强度、钢骨尺寸以及荷载偏心距对其承载性能的影响。提出了内配格构式钢骨-钢管混凝土构件的偏压承载力计算公式,公式计算结果与试验结果吻合较好。 展开更多
关键词 格构式钢骨 钢管混凝土 偏心受压 试验研究 承载力计算方法
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Pterygial body epithelium domination of pterygial proliferation with TCF4 as a potential key factor 被引量:2
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作者 Cong Nie Xin-Chun Zhang +3 位作者 Si-Ying Xu Ya-Dan Quan Zhi-Xin Tang rong lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第9期1467-1474,共8页
AIM: To characterize the proliferative capacity of pterygial epithelium in different regions(head, neck and body) of pterygium and explore the function of transcription factor 4(TCF4) in pterygium proliferation.METHOD... AIM: To characterize the proliferative capacity of pterygial epithelium in different regions(head, neck and body) of pterygium and explore the function of transcription factor 4(TCF4) in pterygium proliferation.METHODS: Thirty pterygium tissues and 10 normal conjunctival tissues were obtained from Zhongshan Ophthalmic Center(ZOC) and Guangdong Eye Bank, respectively. Proliferative capacity of head, neck and body in pterygial epithelium was measured using clonal analysis, fold growth analysis and expression profile of proliferative markers revealed by immunofluorescent staining and real-time PCR. The expression of TCF4 was highlighted by double immunofluorescent staining with other proliferation related markers such as proliferating cell nuclear antigen(PCNA) and ATP-binding cassette subfamily G member 2(ABCG2).RESULTS: The proliferative potential of pterygial epithelium was higher than that of normal conjunctival epithelium. High expression levels of proliferative markers(P63α, PCNA and ABCG2) in pterygial body epithelium were observed in immunofluorescent staining and real-time PCR(P<0.05). Also, epithelial cells isolated from pterygial body demonstrated higher proliferative capacity in clonal analysis and fold growth analysis, than those isolated from the head and neck regions. The TCF4 expression in pterygial epithelium was similar to other proliferative markers(P63α, PCNA and ABCG2), as higher in pterygial body than head and neck. Moreover, TCF4 showed coexpression with other proliferation-related markers(PCNA and ABCG2) in the double immunofluorescent staining experiment.CONCLUSION: The proliferative capacity in pterygial body epithelium is prominent than the head and neck regions, and upregulated TCF4 may be associated with enhanced proliferation in the pterygium. 展开更多
关键词 PTERYGIUM EPITHELIUM PROLIFERATION transcription factor 4
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