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煤层取芯过程中煤芯温度的时变特征

过程工程学报 2023年第6期23卷 925-935页

作者：程括蔺海晓岳高伟梁为民河南理工大学土木工程学院河南焦作454000

井下取芯时煤芯温度直接影响取芯过程中的瓦斯损失量。为了减小瓦斯损失量预测的误差,利用试验与数值模拟相结合的方法,研究了取芯过程煤芯温度场的演化规律。进行取芯深度为40和60 m的现场取芯测温试验,建立取芯钻头-取芯管-煤体的3阶... 详细信息

井下取芯时煤芯温度直接影响取芯过程中的瓦斯损失量。为了减小瓦斯损失量预测的误差,利用试验与数值模拟相结合的方法,研究了取芯过程煤芯温度场的演化规律。进行取芯深度为40和60 m的现场取芯测温试验,建立取芯钻头-取芯管-煤体的3阶段热力学模型并与试验对比,验证该热力学模型具有一定可靠性。建立煤层取芯过程中取芯钻头-取芯管-煤体-煤芯的热力学模型,数值分析不同取芯深度煤层取芯过程煤芯温度的演化规律。研究结果表明,煤层取芯推进阶段取芯管与煤壁摩擦生热;钻进阶段钻头切削煤层生热且与煤壁摩擦生热;退钻阶段取芯管与孔内气体发生热交换散热。不同取芯深度现场测试的取芯管监测点温度与模拟结果的温度变化规律一致,误差为±10%,表明取芯热力学模型可靠。模拟取芯时,热量从钻头处同时向煤芯内部及底部传导,温度沿轴向和径向随时间升高,由于与钻孔内气体换热,峰值温度随时间降低。不同取芯深度的煤层取芯,煤芯中心所达到的最终温度随深度呈指数上升。

关键词：煤层取芯测温取芯深度温度场

碳排放约束下中国省域基础设施投资效率测度及影响因素分析

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资源开发与市场 2022年第5期38卷 554-560页

作者：曹琳剑周詹杭李栋梁赵阔阔天津城建大学经济与管理学院天津300384 天津城镇化与新农村建设研究中心天津300384 广州大学管理学院广东广州510006

从碳排放约束视角出发,利用Super-SBM模型和Malmquist指数对2005—2019年我国30个省份基础设施投资效率分别进行了静态和动态评价,分析了影响投资效率变化的外部因素。结果表明:①静态特征上,我国基础设施投资效率呈波动上升趋势,各省... 详细信息

从碳排放约束视角出发,利用Super-SBM模型和Malmquist指数对2005—2019年我国30个省份基础设施投资效率分别进行了静态和动态评价,分析了影响投资效率变化的外部因素。结果表明:①静态特征上,我国基础设施投资效率呈波动上升趋势,各省份效率逐渐形成“低低集聚、高高集聚”的近“双峰”式演变格局。②动态特征上,我国基础设施全要素生产率呈倒“U”型发展态势,区域层面呈现出“东部>中部>东北>西部”的发展特征。③影响因素上,能源强度对东北和中西部地区效率产生消极影响;技术创新促进了东北和西部地区效率提升;政府支出和金融效率对中西部影响显著为正。结合研究结论,提出促进我国基础设施可持续发展建议。

关键词：基础设施投资效率碳排放非期望Super-SBM模型 Malmquist指数 Tobit模型

Corrigendum to‘New therapy targeting differential androgen receptor signaling in prostate cancer stem/progenitor ***-stem/progenitor cells’

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Journal of Molecular Cell Biology 2020年第12期12卷 991-992页

作者： Soo Ok Lee Zhifang Ma Chiuan-Ren Yeh Jie Luo Tzu-Hua Lin kuo-Pao Lai Shinichi Yam ashita liang liang Jing Tian Lei Li Qi Jiang Chiung-Kuei Huang Yuanjie Niu Shuyuan Yeh and Chawnshang Chang George Whipple Lab for Cancer Research Department of PathologyUniversity of Rochester Medical CenterRochesterNY 14642USA George Whipple Lab for Cancer Research Department of UrologyUniversity of Rochester Medical CenterRochesterNY 14642USA George W hipple Lab for Cancer Research Department of Radiation OncologyUniversity of Rochester Medical CenterRochesterNY 14642USA George Whipple Lab for Cancer Research The Wilmot Cancer CenterUniversity of Rochester Medical CenterRochesterNY 14642USA Department of Urology First Hospital of Shanxi Medical UniversityTaiyuan 030001China Sex Hormone Research Center Department of UrologyThe First Affiliated HospitalXi an Jiaotong UniversityXi an 710061China Chawnshang Chang Sex Hormone Research Center Tianjin Institute of UrologyTianjin Medical UniversityTianjin 300211China Sex Hormone Research Center China Medical University and HospitalTaichung A04

In this article,there were errors in the images presented in Figure 3Ab(bottom left)and Figure 5D(2nd and 4th columns).These were caused by miss-insertion of the images during preparation of the manuscript for *** raw data of the images in Figure 5D were lost,the authors re-performed the whole experiment and provided new similar results(both images and quantitation graphs)for an *** corrected Figure 3Ab left panel and updated Figure 5D are shown as *** details have been corrected only in this corrigendum to preserve the published version of *** authors assure that the original results or conclusions are not altered and they apologize for the mistake.

关键词： Figure corrected details

Development of “Hot Forging Non-quenched and Tempered Steel”

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Development of “Hot Forging Non-quenched and Tempered Steel...

“第十届中国钢铁年会”暨“第六届宝钢学术年会”

作者： Yu Shihchuan liang Shengleo kuo Chunyi Metallurgical Department China Steel Corporation

This article describes development and improvement of forging steels which are free of quenching and *** adding V,Ti and other alloy and controlling rolling technology,the strength and toughness have been ***,by means of controlled cooling after forging,the mechanical properties could be equivalent to conventional quenched and tempered carbon *** is not only energy saving and reduction of carbon emissions but also reducing process cost by 10%to 15%.

关键词： hot forging non-quenched and tempered environment friendly steels

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基于数据挖掘和本体的入侵警报关联模型

吉林大学学报（工学版） 2015年第3期45卷 899-906页

作者：任维武胡亮赵阔吉林大学计算机科学与技术学院长春130022

为了突破入侵检测领域的原有瓶颈,提出了一种新的基于数据挖掘和本体的入侵警报关联模型。该模型通过对底层警报的聚类和分类,发现并且筛选攻击,然后根据已建立的基于本体的攻击知识模型,对这些攻击进行关联,以达到识别、跟踪和预测多... 详细信息

为了突破入侵检测领域的原有瓶颈,提出了一种新的基于数据挖掘和本体的入侵警报关联模型。该模型通过对底层警报的聚类和分类,发现并且筛选攻击,然后根据已建立的基于本体的攻击知识模型,对这些攻击进行关联,以达到识别、跟踪和预测多步攻击的目的。通过对KDD Cup1999和DARPA 2000数据集的模拟实验,验证了模型的有效性。

关键词：计算机工程入侵检测入侵警报关联数据挖掘本体

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植物残体对青藏高原高寒草甸土壤、微生物和胞外酶C∶N∶P化学计量特征的影响

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应用生态学报 2023年第1期34卷 58-66页

作者：肖向前张海阔冯娅斯王吉鹏梁辰飞陈有超朱高荻蔡延江浙江农林大学省部共建亚热带森林培育国家重点实验室/浙江农林大学环境与资源学院杭州311300 成都理工大学生态环境学院成都610059

植物残体是引起土壤、微生物和胞外酶C∶N∶P改变的关键因素,但是其作用机理尚不明确。本研究以青藏高原东缘高寒草甸为对象,通过测定土壤、微生物生物量和胞外酶活性等指标,探究移除地上植物或根系及植物残体添加对土壤、微生物和胞外... 详细信息

植物残体是引起土壤、微生物和胞外酶C∶N∶P改变的关键因素,但是其作用机理尚不明确。本研究以青藏高原东缘高寒草甸为对象,通过测定土壤、微生物生物量和胞外酶活性等指标,探究移除地上植物或根系及植物残体添加对土壤、微生物和胞外酶C∶N∶P的影响。结果表明:与无人为扰动草甸相比,移除地上植物显著降低了土壤C∶N(变幅为-23.7%,下同)、C∶P(-14.7%)、微生物生物生物量C∶P、N∶P,显著提高了微生物生物量C∶N、胞外酶C∶N∶P。与移除地上植物相比,移除地上植物和根系显著降低了土壤C∶N(-11.6%)、C∶P(-24.0%)、N∶P(-23.3%)和微生物生物量C∶N,显著提高了微生物生物量N∶P和胞外酶N∶P;移除地上植物后添加植物残体显著提高了微生物生物量C∶N、C∶P和胞外酶C∶N,显著降低了胞外酶N∶P。与移除地上植物和根系相比,移除地上植物和根系后添加植物残体显著降低了土壤C∶N(-16.4%)、微生物生物量C∶P、N∶P和胞外酶N∶P,显著提高了胞外酶C∶N。综上可知,去除植物显著影响土壤、微生物和胞外酶的C∶N∶P,微生物生物量和胞外酶C∶N∶P对植物残体的响应更为敏感。有无根系是添加植物残体时土壤、微生物和胞外酶的生态化学计量稳定性强弱的关键所在。添加植物残体的措施适用于植物根系尚且完好的草甸,有利于高寒草甸土壤碳固存,对没有根系的草甸土壤可能不适用,会增加土壤CO_(2)排放。

关键词：凋落物高寒草地微生物生物量土壤胞外酶化学计量比

The heritage and cultural values of ancient Chinese maps

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Journal of Geographical Sciences 2017年第12期27卷 1521-1540页

作者： JIANG Lili liang Qizhang QI Qingwen YE Yanjun liang Xun State Key Laboratory of Resources and Environmental Information System CAS Beijing 100101 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China School of Earth Science and Engineering Hebei University of Engineering Handan 056038 Hebei China

Ancient Chinese cartography dates back to the Western Jin Dynasty in the third century. Cartography was initiated during this period by Pei Xiu, a minister and cartographic expert, who suggested six principles of cartography. Pei Xiu, who is known as the father of Chinese cartography, oversaw the completion of the ＂Yu Gong Regional Maps＂, along with 18 articles and the ＂Terrain Fangzhang Map＂（AD 224-271）. This led to a number of subsequent cartographic initiatives including the ＂Wooden Fangzhang Map＂（an administrative map） which was completed by Xie Zhuang, a minister during the Southern Dynasties （AD 502-557）＂Haineihuayi Tu＂（Map of China and its neighbouring countries）（AD 730-805）, drawn by Jia Dan, a cartographer of the Tang Dynasty, and ＂Shouling Tu＂（an administrative map, AD 1031-1095）, drawn by Shen kuo, a scientist during the Northern Song Dynasty. Throughout the 16th century, ancient Chinese cartography developed continuously and cumulatively, and formed the specific characteristics of China ancient cartography. Although Western lati- tude-based and longitude-based mapping techniques introduced to China in AD 1460, the theories and methods of Chinese and Western mapping systems co-existed for over 400 years. The cultural heritage of Chinese cartography can be seen in many famous ancient Chinese maps, including astronomical figures and atlases （world, Chinese, regional, military, water conservancy, historical, and educational maps）, charts, and maps of scenic spots. These have hitherto been kept in well-known archives and institutions across the world. They form an important part of the global cultural heritage of ancient maps and cartography. Given their high cultural value, these maps remain an important point of study. This paper provides a preliminary discussion on the rarity, application, and the historical, scientific, and artistic value of ancient Chinese maps.

关键词： ancient map historical cartography map heritage ancient cultural maps

A new classification of nevus of Ota

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Chinese Medical Journal 2013年第20期126卷 3910-3914页

作者： Huang Wen-hui Wang Hong-wei Sun Qiu-ning Jin Hong-zhong Liu Yue-hua Ma Dong-lai Zuo Ya-gang Zheng He-yi Wan kuo Jing Quan Zhao Yong-liang Chinese Acad Med Sci Peking Union Med Coll Hosp Dept Dermatol Beijing 100730 Peoples R China Chinese Acad Med Sci Peking Union Med Coll Hosp Dept Stomatol Beijing 100730 Peoples R China

Background The nevus of Ota, is a common benign pigmentary dermatosis, mainly involve innervation area of first and second branch of trigeminal nerve. The classification of nevus of Ota was proposed by Tanino, based on 26 cases of nevus of Ota from 1937 to 1940. Studies about its classification are rarely seen in last 70 years, while it is still practical today.

关键词： nevus of Ota classification, trigeminal nerve

A generic approach to the dynamical interpretation of ocean-atmosphere processes

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Acta Oceanologica Sinica 2008年第Z1期27卷 74-92页

作者： X. San liang Courant Institute of Mathematical Sciences New York New York 10012 USA

This paper summarizes the recent development of a portable self-contained system to unravel the intricate multiscale dynamical processes from real oceanic flows, which are in nature highly nonlinear and intermittent in space and time. Of particular focus are the interactions among largescale, mesoscale, and submesoscale *** firsu introduce the concept of scale window, and an orthogonal subspace decomposition technigue called multiscale window transform (MWT). Established on MWT is a rigorous formalism of multiscale transport, perfect transfer, and multiscale conversion, which makes a new methodology, multiscale energy and vorticity analysis (MS-EVA). A direct application of the MS-EVA is the development of a novel localized instability analysis, generalizing the classical notion of hydrodynamic instability to finite amplitude processes on irregularly variable domains. The theory is consistent with the analytical solutions of Eady's model and kuo's model, the benchmark models of baroclinic instability and barotropic instability; it is further validated with a vortex shedding control problem. We have put it to application with a variety of complicated real ocean problems, which would be otherwise very difficult, if not impossible, to tackle. Briefly shown in this paper include the dynamical studies of a highly variable open ocean front, and a complex coastal ocean circulation. In the former, it is found that underlying the frontal meandering is a convective instability followed by an absolute instability, and correspondingly a rapid spatially amplifying mode locked into a temporally growing mode; in the latter, we see a real ocean example of how upwelling can be driven by winds through nonlinear instability, and how winds may excite the ocean via an avenue which is distinctly different from the classical paradigms. This system is mathematically rigorous, physically robust, and practically straightforward.

关键词： Multiscale energy and vorticity analysis multiscale window transform multiscale transport perfect transfer finite-amplitude hydrodynamic instability analysis mean-eddy-turbulence interaction