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地震前后断层测点群体活动的量化指标 被引量:2
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作者 张四新 王双绪 +1 位作者 刘文义 郑申宝 《大地测量与地球动力学》 CSCD 北大核心 2006年第2期53-57,共5页
地震前后,随着构造应力场的增强或减弱,断层测点群体偏离稳态变化的程度随之增大或减小;同时,由于震源体内外介质物性的差异,断层测点之间偏离稳态变化的差异性也随之增大或减小。基于这一事实,采用随机变量的数字指标,提出了一种反映... 地震前后,随着构造应力场的增强或减弱,断层测点群体偏离稳态变化的程度随之增大或减小;同时,由于震源体内外介质物性的差异,断层测点之间偏离稳态变化的差异性也随之增大或减小。基于这一事实,采用随机变量的数字指标,提出了一种反映断层群体活动的量化指标——断层活动强度及非均匀度。结合具体震例对青藏块体东北部、川滇地区的断层水准资料进行了计算,结果表明量化指标在地震前后一般会出现一个明显的增大或减小过程。 展开更多
关键词 地震 断层 群体活动 断层形变 量化指标
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含春矿F1及F2断层落点初探
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作者 黄庆建 《中国高新技术企业》 2015年第17期160-161,共2页
文章根据铅坑井田、含春井田内-20线、20线、-19线、19线之间目前实际揭露情况,对照周边层位、构造特征,进行认真分析、对比、论证,从而判定含F1、含F2断层的具体落点位置,对分析掌握这一块段的构造特征、合理布置地巷探提供了重大的依据。
关键词 含春矿井 井田 断层 地质找煤 含煤规律
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基于张量投票的自动拆分断层方法
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作者 刘旭明 《石油地球物理勘探》 EI CSCD 北大核心 2021年第4期826-832,I0012,I0013,共9页
地质建模时手工拆分断层工作繁琐且十分耗时,而且断层拆分精度受主观因素制约,特别是在复杂断块区域,可能会造成错误的拆分结果。此外,由于不同工区的地质问题不同,解释精度要求也不一致,致使自动拆分断层难度极大。为此,提出了一种基... 地质建模时手工拆分断层工作繁琐且十分耗时,而且断层拆分精度受主观因素制约,特别是在复杂断块区域,可能会造成错误的拆分结果。此外,由于不同工区的地质问题不同,解释精度要求也不一致,致使自动拆分断层难度极大。为此,提出了一种基于张量投票的自动拆分断层方法。该方法的核心是利用张量投票算法计算原始断层点集的方向信息,然后结合断层文件中的空间位置和断棱编号信息,融合现有地质认识,实现断层的自动拆分。具体流程为:(1)将所有散点编码,并以球张量的形式表现;(2)根据尺度参数计算所有散点的球张量场并进行张量投票;(3)对投票后的张量场进行特征值分解,得到所有散点的法向量,进而计算所有散点的瞬时倾角和瞬时倾向;(4)根据断层点集的方向信息和空间位置信息初步拆分断层;(5)在初步拆分基础上融合地质认识精细拆分断层。模拟数据和实际数据应用表明,基于张量投票的自动拆分断层方法可极大提高断层拆分命名的工作效率和拆分精度。 展开更多
关键词 张量投票 断层点 自动拆分断层 断棱 产状
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单子电发射断层成像/CT同机图像融合显像对乳腺癌骨病灶的鉴别诊断价值
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作者 张伟 《中国医药指南》 2016年第30期122-122,共1页
目的研究分析在乳腺癌骨病灶的鉴别诊断中使用单子电发射断层成像/CT同机图像融合显像的效果与价值。方法选取我院2014年3月至2015年3月收治的68例乳腺癌患者(共136个病灶),对其进行局部单子电发射断层成像/CT同机图像融合显像,观察其... 目的研究分析在乳腺癌骨病灶的鉴别诊断中使用单子电发射断层成像/CT同机图像融合显像的效果与价值。方法选取我院2014年3月至2015年3月收治的68例乳腺癌患者(共136个病灶),对其进行局部单子电发射断层成像/CT同机图像融合显像,观察其诊断价值。结果根据最终临床诊断标准,良性病灶89个,占65.4%;恶性病灶47个,占34.6%。通过SPECT/CT同机图像融合显像检查,良性病灶81个,占59.6%;恶性病灶55个,占40.4%。另外,SPECT/CT同机图像融合显像诊断的准确率为90.8%,诊断灵敏度为92.4%,特异度为91.3%。结论单子电发射断层成像(SPECT)/CT同机图像融合显像在乳腺癌骨病灶的诊断应用中,具有较高的准确率,尤其是针对单独全身骨显像难以确诊的乳腺癌患者,其确诊率较高,其具有较高的临床应用价值。 展开更多
关键词 单子发射断层成像 CT同机图像融合显像 乳腺癌骨病灶 鉴别诊断价值
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数学学习管理的润物“细”无声
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作者 武婷婷 《试题与研究(教学论坛)》 2020年第29期188-188,共1页
面对新生越来越薄弱的数学基础,教师在新课教 学之前要先摸查每一位学生的知识断层点,再制定方法进行补 偿,同时要培养学生良好的自我学习管理能力,只有夯实基础 才能高屋建瓴。
关键词 数学学习管理 断层点
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Idiopathic sclerosing encapsulating peritonitis:Abdominal cocoon 被引量:17
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作者 Jenny N Tannoury Bassam N Abboud 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第17期1999-2004,共6页
Abdominal cocoon,the idiopathic form of sclerosing encapsulating peritonitis,is a rare condition of unknown etiology that results in an intestinal obstruction due to total or partial encapsulation of the small bowel b... Abdominal cocoon,the idiopathic form of sclerosing encapsulating peritonitis,is a rare condition of unknown etiology that results in an intestinal obstruction due to total or partial encapsulation of the small bowel by a f ibrocollagenous membrane.Preoperative diagnosis requires a high index of clinical suspicion.The early clinical features are nonspecif ic,are often not recognized and it is diff icult to make a def inite pre-operative diagnosis.Clinical suspicion may be generated by the recurrent episodes of small intestinal obstruction combined with relevant imaging f indings and lack of other plausible etiologies.The radiological diagnosis of abdominal cocoon may now be conf idently made on computed tomography scan.Surgery is important in the management of this disease.Careful dissection and excision of the thick sac with the release of the small intestine leads to complete recovery in the vast majority of cases. 展开更多
关键词 Peritonitis Sclerosis Encapsulate Intestinal obstruction Computed tomography scan Surgery
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Pneumatosis cystoides intestinalis:A single center experience 被引量:14
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作者 Zulfu Arikanoglu Erhan Aygen +5 位作者 Cemalettin Camci Sami Akbulut Murat Basbug Osman Dogru Ziya Cetinkaya Cuneyt Kirkil 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第5期453-457,共5页
AIM: To share our experience of the management and outcomes of patients with pneumatosis cystoides in- testinalis (PCI). METHODS: The charts of seven patients who under- went surgery for PCI between 2001 and 2009 ... AIM: To share our experience of the management and outcomes of patients with pneumatosis cystoides in- testinalis (PCI). METHODS: The charts of seven patients who under- went surgery for PCI between 2001 and 2009 were re- viewed retrospectively. Clinical features, diagnoses and surgical interventions of patients with PCI are discussed. RESULTS: Seven patients with PCI (3 males, 4 fe- males; mean age, 50 ~ 16.1 years; range, 29-74 years) were analyzed. In three of the patients, abdominal pain was the only complaint, whereas additional vomiting and/or constipation occurred in four. Leukocytosis was detected in four patients, whereas it was within normal limits in three. Subdiaphragmatic free air was observed radiologically in four patients but not in three. Six of the patients underwent an applied lapa- rotomy, whereas one underwent an applied explorative laparoscopy. PCI localized to the small intestine only was detected in four patients, whereas it was localized to the small intestine and the colon in three. Three patients underwent a partial small intestine resection and four did not after PCI was diagnosed. Five patients were diagnosed with secondary PCI and two with pri- mary PCI when the surgical findings and medical his- tory were assessed together. Gastric atony developed in one case only, as a complication during a postopera- tive follow-up of 5-14 d. CONCLUSION: Although rare, PCl should be consid- ered in the differential diagnosis of acute abdomen. Diagnostic laparoscopy and preoperative radiological tests, including computed tomography, play an impor- tant role in confirming the diagnosis. 展开更多
关键词 Pneumatosis cystoides intestinalis Perito-neal free air Radiological tools DIAGNOSIS
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Research on Characteristics of Focal Rupture of the Zhangbei-Shangyi Earthquake by Means of Deformation Field Obtained by Spaceborne D-INSAR 被引量:3
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作者 ShanXinjian MaJin +3 位作者 SongXiaoyu WangChao LiuJiahang ZhangGuifang 《Earthquake Research in China》 2003年第2期113-121,共9页
In the last ten years, the D_InSAR (Differential Interferometric Synthetic Aperture Radar) technique has proved very useful; it has been a new space observation technique with great potential. Investigating seismic fo... In the last ten years, the D_InSAR (Differential Interferometric Synthetic Aperture Radar) technique has proved very useful; it has been a new space observation technique with great potential. Investigating seismic focus rupture information using D_InSAR is a scientific issue to which more attention is being paid. In this paper, the basic theory of seismic focus dislocation models is discussed briefly. Based on a map of the interferometric deformation field of the Zhangbei_Shangyi earthquake from Jan.10, 1998, and applying the seismic focus dislocation model within elastic half_space medium; some geometrical and kinematical characteristics of the main seismic fault are deduced. Results were as follows: the seismic break surface of the Zhangbei_Shangyi earthquake is left_slip and thrust fault, striking in SEE_NWW 272°with dip angle 46°; rupture direction is unilateral faulting from SEE to NWW; length of rupture zone is 9km, width is 8km, and depth is 8km, the displacement vector of three directions are 290mm, 560mm and 0mm. 展开更多
关键词 D-INSAR INTERFEROGRAM Focal dislocation Focal characteristics Zhangbei-Shangyi earthquake
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Research on focal nodular hyperplasia with MSCT and postprocessing 被引量:2
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作者 Yuan-Jian Liu Wei-Jun Fan +6 位作者 Zhi-Dong Yuan Peng-Cheng Liu Chun-Rong Wang Wei-Qiang Yan Su-Mei Wang Jun-Hui Chen Zheng Liu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第38期4838-4843,共6页
AIM: To investigate and evaluate the pathological features and diagnostic value of focal nodular hyperplasia (FNH) with multiection spiral computed tomography (MSCT) and postprocessing. METHODS: A total of 25 pa... AIM: To investigate and evaluate the pathological features and diagnostic value of focal nodular hyperplasia (FNH) with multiection spiral computed tomography (MSCT) and postprocessing. METHODS: A total of 25 patients with FNH who had undergone MSCT and postprocessing were included in the investigation. All patients had been pathologically or clinically confirmed with FNH. A number of 75 cases of hepatic carcinomas, hemangiomas and adenomas were randomly selected at a same period for a comparative study. RESULTS: There was a single focus in 22 cases and multiple foci in 3 cases. On the plain scan, 17 lesions showed hypodensity, 7 isodensity and 4 hyperdensity (the case with fatty liver). With contrast, 28 lesions were enhanced evenly or in the nodules in the arterial phase; 13 lesions still showed hyperdensity, 11 lesions isodensity and 4 lesions hypodensity in the parenchymatous phase; in the delayed phase only 5 lesions showed hyperdensity but 9 lesions showed isodensity or slight hypodensity and 14 lesions showed hypodensity. Twelve lesions of 28 had central asteroid scars. Thickened feeding arteries in postprocessing were seen in 24 lesions, and were integrated into the parenchymatous lesions with a gradual and smooth course. On the contrary, there were no artery penetrated into the lesion found in any of comparative hepatic tumors. CONCLUSION: Doctors could make a correct diagnosis and differentiation of FNH on evaluation of the characteristic appearance on MSCT with postprocessing, 展开更多
关键词 ANGIOGRAPHY Computer-assisted imageprocessing Focal nodular hyperplasia Liver diseases X-ray Computed tomography
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Fracture Characters and Seismogenic Fault of the Yajiang Earthquake Sequence with M_S6.0 in Sichuan in 2001
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作者 LongSisheng 《Earthquake Research in China》 2004年第3期212-224,共13页
The Yajiang earthquake sequence in 2001, with the major events of M S 5.1 on Feb. 14 and of M S 6.0 on Feb.23, are significant events in the Sichuan region during the last 13 years. Eighty-eight earthquakes in the seq... The Yajiang earthquake sequence in 2001, with the major events of M S 5.1 on Feb. 14 and of M S 6.0 on Feb.23, are significant events in the Sichuan region during the last 13 years. Eighty-eight earthquakes in the sequence with at least 5 distinct onset parameters for each recorded by the Sichuan Seismic Network in the period of Jan. 1 through June 30, 2001 were chosen for this study. The events are relocated and the focal mechanism is derived from P-wave onsets for 13 events with relatively larger magnitudes. The focal depth of all earthquakes fall between a range of 2km to 16km, with dominant distribution between 9km to 11km. The foreshocks, the M S5.1 earthquake and the M S6.0 earthquake and their aftershocks are all located close to the Zihe fault and the dominant epicentral distribution is in NW direction, identical to that of the fault. The fracture surface of the focal mechanism is determined in accordance to the mass transfer orientation in the recent earth deformation field in the Yajiang region. The P axes of the principal compressive stress in focal mechanism solutions of the 13 events show bigger vertical components, and the horizontal projection trending SE. The earthquakes are of left-lateral, strike-slip normal, and normal strike-slip types. The rupture surface of most earthquakes strike NW-SE, dipping SW. Based on the above information, we conclude that the Zihe fault that crosses the earthquake area, striking NW and dipping SW, is the seismogenic fault for the Yajiang earthquake sequence. 展开更多
关键词 Yajiang earthquake sequence Zihe fault Fracture characters Focal stress field Seismogenic fault
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Improvements in seismic event locations in a deep western U.S. coal mine using tomographic velocity models and an evolutionary search algorithm 被引量:7
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作者 LURKA Adam SWANSON Peter 《Mining Science and Technology》 EI CAS 2009年第5期599-603,共5页
Methods of improving seismic event locations were investigated as part of a research study aimed at reducing ground control safety hazards. Seismic event waveforms collected with a 23-station three-dimensional sensor ... Methods of improving seismic event locations were investigated as part of a research study aimed at reducing ground control safety hazards. Seismic event waveforms collected with a 23-station three-dimensional sensor array during longwall coal mining provide the data set used in the analyses. A spatially variable seismic velocity model is constructed using seismic event sources in a passive tomographic method. The resulting three-dimensional velocity model is used to relocate seismic event positions. An evolutionary optimization algorithm is implemented and used in both the velocity model development and in seeking improved event location solutions. Results obtained using the different velocity models are compared. The combination of the tomographic velocity model development and evolutionary search algorithm provides improvement to the event locations. 展开更多
关键词 seismic event location tomographic velocity model an evolutionary search algorithm
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EDGE non-invasive radiosurgery for gastric neuroendocrine hepatic portal lymph node metastases:a case report
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作者 Qianqian Yu Yang Tang +1 位作者 Liang Zhuang Xianglin Yuan 《Oncology and Translational Medicine》 2018年第5期215-218,共4页
Treating metastatic gastric neuroendocrine neoplasms (gNENs) is challenging, especially for those with progressive disease during somatostatin analog processing. In this report, we present a case of a welldifferenti... Treating metastatic gastric neuroendocrine neoplasms (gNENs) is challenging, especially for those with progressive disease during somatostatin analog processing. In this report, we present a case of a welldifferentiated grade 2, type 3 gNEN with metastatic hepatic portal lymph nodes. EDGE non-invasive radiosurgery (800 cGy x 5 F) was performed to radiate the metastatic hepatic portal lymph nodes. Three months after the hyperfractionated radiotherapy, no signs of metastatic hepatic portal lymph nodes were observed using 8Ga-dotatate positron emission tomography-computed tomography or magnetic resonance imaging. Therefore, EDGE non-invasive radiosurgery could be a potential option for treating local metastatic nodes. 展开更多
关键词 gastric neuroendocrine neoplasm (gNEN) hepatic portal lymph node metastases EDGEnon-invasive radiosurgery
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A complicated case of lung cancer and pulmonary tuberculosis initially presented with painful scapular metastasis in other side 被引量:1
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作者 Hassan-Ali Mohebbi Amin Saburi +1 位作者 Mohammad-Hasan Bagheri Ehsan Saburi 《The Chinese-German Journal of Clinical Oncology》 CAS 2012年第5期294-296,共3页
We report a 43-year-old man who presented with a right painful shoulder mass and bilateral lung masses in computed tomography(CT).Scapular mass was excised and pathology report demonstrated high-grade metastatic tumor... We report a 43-year-old man who presented with a right painful shoulder mass and bilateral lung masses in computed tomography(CT).Scapular mass was excised and pathology report demonstrated high-grade metastatic tumor.Same side lung biopsy and histopathological study characterized tuberculosis but biopsy of the left lung lesion identified adenocarcinoma of the lung.The final diagnosis was right scapular metastatic lesion from left lung adenocarcinoma.Musculoskeletal symptoms are commonly encountered in lung malignancies due to paraneoplastic syndrome or hematogenous metastasis but scapular metastasis on the other side as the presentation of lung cancer is extremely rare. 展开更多
关键词 lung cancer (LC) SCAPULA tuberculosis METASTASIS ADENOCARCINOMA
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Clinical Features and Prognosis in 21 Patients with Extrinsic Allergic Alveolitis 被引量:5
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作者 Ping Wang Zuo-jun Xu +4 位作者 Wen-bing Xu Ju-hong Shi Xin-lun Tian Rui-e Feng Yuan-jue Zhu 《Chinese Medical Sciences Journal》 CAS CSCD 2009年第4期202-207,共6页
Objective To assess the spectrum of causes, clinical features, differences between disease phases, and prognosis of extrinsic allergic alveolitis (EAA). Methods Patients with EAA diagnosed at Peking Union Medical C... Objective To assess the spectrum of causes, clinical features, differences between disease phases, and prognosis of extrinsic allergic alveolitis (EAA). Methods Patients with EAA diagnosed at Peking Union Medical College Hospital from August 1983 to May 2007 were analyzed retrospectively. Their medical records were examined to gather clinical, laboratorial, radiological, and histopathological data. Patients were divided to three phases (acute, subacute, and chronic) according to clinical presentations. Follow-up data regarding treatment response, subsequent radio- logical and pulmonary function studies, and clinical outcomes were collected. Results A total of 21 cases were enrolled. Among them, 11 were subacute, 10 were chronic. The most common exposure was pet birds (6 cases, 28.6%). The primary abnormality of pulmonary function was restriction and/or reduction in diffusing capacity (12 cases, 63.2%). The most common findings on high-resolution computed tomography (HRCT) were ground-glass opacities (13 cases, 68.4%) and centri- lobular nodules (8 cases, 42.1%). Airway obstruction in pulmonary function test, emphysema, hmg cysts, and fibrosis on HRCT were more frequently seen in chronic than in subacute patients, though the differences were not statistically significant. Bronchoalveolar lavage fluid (BALF) showed lymphocytosis. The total'cell count and the percentage of neutrophils were significantly higher in subacute than in chronic patients (P〈0.05). Nonnecrotizing granulomas were seen in 8 (47.1%) cases. Improvement or normalization in symptoms, radiography, and pulmonary function test after treatment were seen in all 18 patients with avail- able follow-up data. Five patients recurred. Conclusions The characteristic abnormalities of pulmonary function, findings on HRCT, and pa- thology are essential for all phases of EAA, and the atypical manifestations such as obstruction and fibrosis can also be present frequently, particularly in chronic cases. Differential cell counts of BALF are related to the phase of the disease. The treatment response and prognosis of EAA are good. 展开更多
关键词 extrinsic allergic alveolitis bronchoalveolar lavage fluid RADIOGRAPHY HISTOPATHOLOGY PROGNOSIS
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Pulmonary lymphoma: computed tomography features with pathologic correlation
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作者 Miaoyu Zeng Zhenjun Zhao +2 位作者 Jine Zhang Jinlei Li Yanhui Liu 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第11期632-635,共4页
Objective: The aim of this study was to analyze the CT and pathology features of pulmonary lymphoma and to improve the understanding of this disease. Methods: The CT findings of 23 cases with pulmonary lymphoma were r... Objective: The aim of this study was to analyze the CT and pathology features of pulmonary lymphoma and to improve the understanding of this disease. Methods: The CT findings of 23 cases with pulmonary lymphoma were retrospectively analyzed and correlated with histopathology. Results: Of the 23 cases with pulmonary lymphoma, there were Hodgkin lymphoma (5 cases) and non-Hodgkin lymphoma (18 cases). Multiple lesions were assessed in 16 cases and single lesion in 7 cases. The imaging findings were classified into 3 types: lobar and segmental involvement type (9/23 cases, 39.13%), nodular or mass-like involvement type (8/23 cases, 34.78%) and mixed type (6/23 cases, 26.09%). Air bronchogram sign (14/23 cases, 60.8%), CT angiogram sign (12/23 cases, 52.17%), ground glass opacity nodules (3/23 cases, 13.04%) and lesion across pulmonary lobes (4/23,17.39%) were the characteristic features of pulmonary lymphoma. Conclusion: Relative characteristic CT features of pulmonary lymphoma could be revealed, which shows clinical significance in the diagnosis of the disease. 展开更多
关键词 lung neoplasms LYMPHOMA TOMOGRAPHY X-ray computed PATHOLOGY
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群聚分析法:原理、争议及应用前景 被引量:13
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作者 张航 范子英 《数量经济技术经济研究》 CSSCI CSCD 北大核心 2019年第9期152-168,共17页
系统性地介绍群聚分析法(Bunching Approach)这一新兴实证方法。研究方法:通过文献整理,解析群聚分析法的原理和估计方法,梳理该方法在文献中的应用方向和尚存的争议,并展望其应用前景。研究发现:群聚分析法的应用对象为非连续型制度中... 系统性地介绍群聚分析法(Bunching Approach)这一新兴实证方法。研究方法:通过文献整理,解析群聚分析法的原理和估计方法,梳理该方法在文献中的应用方向和尚存的争议,并展望其应用前景。研究发现:群聚分析法的应用对象为非连续型制度中的制度弯折点(Kinkpoints)和制度断层点(Notchpoints),通过对群聚式分布进行高阶回归以获得反事实分布,群聚分析法得以准确测度个体行为弹性、制度规避程度和最优化摩擦等重要经济参数。研究创新:首次在国内介绍群聚分析法,并提出有潜力的应用领域。研究价值:群聚分析法已在国外研究中得到了广泛使用,但在国内的应用还处于萌芽阶段,本文旨在为该方法在国内经济研究中的应用打下基础。 展开更多
关键词 群聚分析法 制度弯折 制度断层点 弹性
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