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| 1 | Deep learning based classification of rock structure of tunnel face显示文摘The automated interpretation of rock structure can improve the efficiency,accuracy,and consistency of the geological risk assessment of tunnel face.Because of the high uncertainties in the geological images as a result of different regional rock types,as well as in-situ conditions(e.g.,temperature,humidity,and construction procedure),previous automated methods have limited performance in classification of rock structure of tunnel face during construction.This paper presents a framework for classifying multiple rock structures based on the geological images of tunnel face using convolutional neural networks(CNN),namely Inception-ResNet-V2(IRV2).A prototype recognition system is implemented to classify 5 types of rock structures including mosaic,granular,layered,block,and fragmentation structures.The proposed IRV2 network is trained by over 35,000 out of 42,400 images extracted from over 150 sections of tunnel faces and tested by the remaining 7400 images.Furthermore,different hyperparameters of the CNN model are introduced to optimize the most efficient algorithm parameter.Among all the discussed models,i.e.,ResNet-50,ResNet-101,and Inception-v4,Inception-ResNet-V2 exhibits the best performance in terms of various indicators,such as precision,recall,F-score,and testing time per image.Meanwhile,the model trained by a large database can obtain the object features more comprehensively,leading to higher accuracy.Compared with the original image classification method,the sub-image method is closer to the reality considering both the accuracy and the perspective of error divergence.The experimental results reveal that the proposed method is optimal and efficient for automated classification of rock structure using the geological images of the tunnel face. | Jiayao Chen Tongjun Yang Dongming Zhang Hongwei Huang Yu Tian | 2021 | Geoscience Frontiers2021，12，1： | 13 |
| 2 | Active velocity tomography for assessing rock burst hazards in a kilometer deep mine显示文摘Active velocity tomography was used to determine the stress state and rock burst hazards in a deep coal mine. The deepest longwall face, number 3207 in the Xingcun colliery, was the location of the field trials. The positive correlation between stress and seismic velocity was used to link the velocity data with stratum stresses. A GeoPen SE2404NT data acquisition system was used to collect seismic data from 300 g explosive charges fired by instantaneous electric detonator and located in the tail entry. The geophones were installed on the rock bolts in the head entry of LW3207. Velocity inversion shows an inhomogeneous distribution of stress in the longwall face that could not be obtained from theory or numerical simulations. Three abnormally high P-wave velocity regions were identified that were located on the corners of the two roadways and at the face end near the rail entry side. The maximum velocity gradient is located at the open cut off near the rail entry and is the area most dangerous for rock burst. Mining-induced tremors recorded by a micro-seismic monitoring system demonstrated that the position of energy release during mining coincides with the high velocity gradient area. This technology aids tech- nicians in the coal mine as they design measures to weaken or eliminate potential danger during subse- quent mining. | He Hu Dou Linming Li Xuwei Qiao Qiuqiu Chen Tongjun Gong Siyuan | 2011 | Mining Science and Technology2011，21，5： | 9 |
| 3 | Comparison between several seismic inversion methods and their application in mountainous coal fields of western China显示文摘With the objective of establishing the necessary conditions for 3D seismic data from mountainous areas in western China, we compared the application results of wave impedance technology in the lithology and exploration of coal fields. First, we introduce principles and features of three kinds of inversion methods. i.e., Model-Based Inversion, Constrained Sparse Spike Inversion (CSSI) and Geology-Seismic Feature Inversion. Secondly, these inversion methods are contrasted in their application to 3D seismic data from some coalfields in western China. The main information provided by the research includes: improving the vertical resolution of coal deposit strata, inferring lateral variation of the lithology and predicting coal seams and their roof lithology. Finally, the comparison between the three methods shows that the model-based inversion has the higher resolution, while CSSI inversion has better waveform continuity. The geology-seismic feature inversion requires information from a large number of wells and many types of logging curves of good quality. All three methods can meet the requirements of seismic exploration for lithological exploration in coal fields. | XU Yongzhong CHEN Tongjun CHEN Shizhong HUANG Weichuan WU Gang | 2010 | Mining Science and Technology2010，20，4： | 9 |
| 4 | Acupuncture at Waiguan (TE5) influences activation/deactivation of functional brain areas in ischemic stroke patients and healthy people A functional MRI study显示文摘In the present study, 10 patients with ischemic stroke in the left hemisphere and six healthy controls were subjected to acupuncture at right Waiguan (TE5). In ischemic stroke subjects, functional MRI showed enhanced activation in Broadmann areas 5, 6, 7, 18, 19, 24, 32, the hypothalamic inferior lobe, the mamillary body, and the ventral posterolateral nucleus of the left hemisphere, and Broadmann areas 4, 6, 7, 18, 19 and 32 of the right hemisphere, but attenuated activation of Broadmann area 13, the hypothalamic inferior lobe, the posterior lobe of the tonsil of cerebellum, and the culmen of the anterior lobe of hypophysis, in the left hemisphere and Broadmann area 13 in the right hemisphere. In ischemic stroke subjects, a number of deactivated brain areas were enhanced, including Broadmann areas 6, 11, 20, 22, 37, and 47, the culmen of the anterior lobe of hypophysis, alae lingulae cerebella, and the posterior lobe of the tonsil of cerebellum of the left hemisphere, and Broadmann areas 8, 37, 45 and 47, the culmen of the anterior lobe of hypophysis, pars tuberalis adenohypophyseos, inferior border of lentiform nucleus, lateral globus pallidus, inferior temporal gyrus, and the parahippocampal gyrus of the right hemisphere. These subjects also exhibited attenuation of a number of deactivated brain areas, including Broadmann area 7. These data suggest that acupuncture at Waiguan specifically alters brain function in regions associated with sensation, vision, and motion in ischemic stroke patients. By contrast, in normal individuals, acupuncture at Waiguan generally activates brain areas associated with insomnia and other functions. | Junqi Chen Yong Huang Xinsheng Lai Chunzhi Tang Junjun Yang Hua Chen Tongjun Zeng Junxian Wu Shanshan Qu | 2013 | Neural Regeneration Research2013，8，3： | 8 |
| 5 | GaN-based substrates and optoelectronic materials and devices显示文摘In order to solve the problems of GaN heteroepitaxy on sapphire substrate,some techniques were explored.Freestanding GaN substrates have been made by hydride vapor phase epitaxy(HVPE),laser lift-off(LLO),and chemical mechanical polishing techniques.Wafer bending and cracking in the HVPE growth were partly settled by pulsed flow modulation method.High-crystal quality was established for 1.2 mm thick GaN substrate by X-ray diffraction measurement,in which the full width of half maximum values were 72,110 arcsec for(102),(002)peaks.A novel micro-size patterned sapphire substrate(PSS)and a nano PSS were also fabricated.High-power vertical structure light emitting diodes(VSLEDs)have been developed by Au–Sn eutectic wafer bonding,homemade micro-area LLO,and light extraction structure preparation.The high-injection-level active region with low temperature GaN sandwiched layers was used for lowefficiency droop.The light output power of VSLED was achieved as 400 mW driven at 350 mA,and the dominant wavelength is about 460 nm.The structures and properties of strain modulated superlattices(SLs)and quantum wells as well as advanced simulation of carriers transport across the electron blocking layer were investigated in laser diodes.The hole concentration was achieved as high as1.6 9 1018cm-3in AlGaN/GaN SLs:Mg by inserting an AlN layer.High-quality AlGaN epilayers and structures were grown by MOCVD.Some device structures of UV LEDs and detectors were demonstrated.The emission wavelength of 262 nm UV LED has been successfully fabricated.At last,high-quality InN and InGaN materials for solar cell were grown by boundary-temperature-controlled epitaxy and growth-temperature-controlled epitaxy.Hall-effect measurement showed a recorded electron mobility of 3,280 cm2/(V s)and a residual electron concentration of 1.47 9 1017cm-3at 300 K. | Guoyi Zhang Bo Shen Zhizhong Chen Xiaodong Hu Zhixin Qin Xinqiang Wang Jiejun Wu Tongjun Yu Xiangning Kang Xingxing Fu Wei Yang Zhijian Yang Zhizhao Gan | 2014 | Chinese Science Bulletin2014，59，12： | 4 |
| 6 | Activated and deactivated functional brain areas in the Deqi state: A functional MRI study显示文摘We compared the activities of functional regions of the brain in the Deqi versus non-Deqi state, as reported by physicians and subjects during acupuncture. Twelve healthy volunteers received sham and true needling at the Waiguan (TE5) acupoint. Real-time cerebral functional MRI showed that compared with non-sensation after sham needling, true needling activated Brodmann areas 3, 6, 8, 9, 10, 11, 13, 20, 21, 37, 39, 40, 43, and 47, the head of the caudate nucleus, the parahippocampal gyrus, thalamus and red nucleus. True needling also deactivated Brodmann areas 1, 2, 3, 4, 5, 6, 7, 9, 10, 18, 24, 31, 40 and 46. | Yong Huang Tongjun Zeng Guifeng Zhang Ganlong Li Na Lu Xinsheng Lai Yangjia Lu Jiarong Chen | 2012 | Neural Regeneration Research2012，7，30： | 4 |
| 7 | Spectral decomposition method for predicting magmatic intrusion into a coal bed显示文摘Accurate prediction of magmatic intrusion into a coal bed is illustrated using the method of seismic spectral decomposition.The characteristics of coal seismic reflections are first analyzed and the effect of variable time windows and domain frequencies on the spectral decomposition are examined.The higher domain frequency of coal bed reflections using the narrower STFT time window,or the smaller ST scale factor,are acceptable.When magmatic rock intrudes from the bottom of the coal bed the domain frequency of the reflections is decreased slightly,the frequency bandwidth is narrowed correspondingly,and the response from spectral decomposition is significantly reduced.Intrusion by a very thin magmatic rock gives a spectral decomposition response that is just slightly less than what is seen from a normal coal bed.Results from an actual mining area were used to validate the method.Predicting the boundary of magmatic intrusions with the method discussed herein was highly accurate and has been validated by observations from underground mining. | Wang Xin Chen Tongjun Cui Ruofei Xu Yongzhong | 2012 | International Journal of Mining Science and Technology2012，22，4： | 3 |
| 8 | Specific cerebral activation following true and sham Waiguan(SJ 5) needling Functional magnetic resonance imaging evidence显示文摘Positive activation and negative activation of glucose metabolism can be detected in different brain regions under acupuncture conditions using functional magnetic resonance imaging(fMRI) which reveals acupoint function and location-acupoint specificity.This study observed the regional cerebral activation of the Waiguan(SJ 5) acupoint following true needling at the true Waiguan acupoint,sham needling at the true Waiguan acupoint and true needling at a sham point using fMRI.The fMRI results demonstrated that compared with sham needling,true needling at Waiguan activated the BA8 area and left cerebellum.Compared with needling at the sham point,needling at Waiguan activated the BA2 area,the left cerebellum and the right inferior semilunar lobule.Thus the activated brain areas caused by needling Waiguan may be the basis for treatment of certain diseases. | Yong Huang Xinsheng Lai Baoci Shan Chunzhi Tang Junjun Yang Tongjun Zeng Guifeng Zhang Jiarong Chen Yangjia Lu | 2010 | Neural Regeneration Research2010，5，22： | 3 |
| 9 | Rockburst hazard determination by using computed tomography technology in deep workface显示文摘 | Dou Linming Chen Tongjun Gong Siyuan | 2011 | Safety Science2011，50，4： | 1 |
| 10 | Rockburst hazard determination by using computed tomography technology in deep workface显示文摘 | Linming Dou Tongjun Chen Siyuan Gong Hu He Shibin Zhang | 2011 | Safety Science2011，，4： | 1 |
| 11 | Rockburst hazard determination by using computed tomography technology in deep workface显示文摘 | LINMING DOU TONGJUN CHEN SIYUAN GONG | 2012 | Safety Science2012，50，： | 1 |
| 12 | Method to locate igneous rock intrusion of coal bed using P-wave data 显示文摘 | Chen Tongjun Cui Ruofei Wang Xin | 2009 | Procedia Earth and Planetary Science2009，，1： | 1 |
| 13 | Rockburst hazard determination by using computed to- mography technology in deep workface显示文摘 | DOU Linming CHEN Tongjun GONG Siyuan | 2012 | Safety Sci- ence2012，50，4： | 1 |
| 14 | Rockburst hazard determination by using computed tomography technology in deep workface显示文摘 | Linming Dou Tongjun Chen Siyuan Gong Hu He Shibin Zhang | 2011 | Safety Science2011，，4： | 1 |
| 15 | Luminescence Degradation of In GaN/GaN Violet LEDs显示文摘 | Tongjun Yu Shuping Shang Zhizhong Chen | 2007 | Journal of Luminescence2007，，： | 1 |
| 16 | Fabrication of dodecagonal pyramid on nitrogen face GaN and its effect on the light extraction显示文摘Wet etching has been widely used in defect evaluation for Ga-face GaN and surface roughness for N-face GaN dodecagonal pyramids has been fabricated on laser-lift-off N-face GaN by hot phosphor acid etching.The dodecagonal pyramid shows twelve facets including six{20-2-3}and six{22-4-5}planes.From cross-sectional TEM image,it is shown that the pyramid corresponds to the top of the edge dislocation.Compared with hexagonal pyramid-surface light emitting diodes(LEDs)etched by commonly used photoelectrochemical(PEC)process in KOH aqueous,the dodecagonal pyramid-surface LEDs show improved light extraction efficiency because of more facets,which effectively reduces the total internal reflection. | QI ShengLi,CHEN ZhiZhong,SUN YongJian,FANG Hao,TAO YueBin,SANG LiWen,TIAN PengFei,DENG JunJing,ZHAO LuBing,YU TongJun,QIN ZhiXin&ZHANG GuoYi State Key Laboratory for Artificial Microstructure and Mesoscopic Physics,School of Physics,Peking University,Beijing 100871,China | 2010 | Science China(Technological Sciences)2010，53，3： | 0 |
| 17 | A Pregnant Woman Died of Sudden Cardiac Death:Should Esophageal Foreign Body Be Considered an Inductive Factor?A Case Report and Literature Review显示文摘Here,we report a case of acute attack of coronary heart disease(CHD).A 47‑year‑old pregnant woman with gestational hypertension developed sudden‑onset chest tightness,palpitations,dyspnea,and cyanosis of the face and lips after admission.Her blood pressure was 180/110 mmHg and her blood oxygen saturation was 45%at that time.After cardiopulmonary resuscitation,a weak heartbeat was restored,but oxygen saturation did not increase significantly.Therefore,she was transferred to the intensive care unit;however,she died after 21 days of admission.Autopsy findings revealed that a foreign body was embedded in the esophagus near the right piriform,and her heart weighed 392 g;histopathological examination revealed CHD,thrombosis in the lumen of the right coronary artery,cardiomyocyte hypertrophy,vascular hyaline degeneration in arterioles,neutrophils in the bronchiole and alveolar.All the tested samples yielded negative toxicological results.Clinical status and autopsy findings were not compatible with a diagnosis of peripartum cardiomyopathy.The patient’s sudden death was attributed to CHD,and esophageal foreign‑body impaction was considered to be concomitant phenomenon.Our findings might help in increasing the awareness between esophageal foreign‑body impaction and sudden cardiac death and they can also help in clarifying that understanding the primary cause of death is the key to resolving an iatrogenic medical tangle. | Chang Cao Mingming Li Zhanzhan Liu Shiyong Fang Gang Chen Guang Chen Tongjun Ma Xuyang Zhu Xiang Xu | 2022 | Journal of Forensic Science and Medicine2022，8，4： | 0 |
| 18 | 6-26 Conceptual Design of a 3.6 T Curved Tilted Solenoid Superconducting Magnet显示文摘The type of tilted solenoid is a novel approach to be used in superconducting dipole magnet design. The dipolefield is obtained by using concentric pairs of helically-wound coils that are tilted at opposite angles; this effectivelycancels the solenoid component of the field and adds the dipole content of each layer. Fig. 1 shows a dipole magnetcomposed of a pair of coils.According to the principle of modulating the tilted solenoid, we proposed a conceptual design of curved superconductingmagnet. The magnet with 150 mm bore diameter is curved 60 ? at a radius of 833 mm. The magnetconsists of 10 layers and the thickness of each layer is 5 mm. It could be cooled by a GM refrigerator. The detailedparameters of magnet are showed in Table 1. | Liang Yu Wu Wei Yang Tongjun Chen Yuquan | 2014 | IMP & HIRFL Annual Report2014，，1： | 0 |
| 19 | Quench Analysis of CiADS Superconducting Magnet显示文摘The models of quench analysis of CiADS superconducting magnets are displayed in Fig.1.Three structures of superconducting magnet are designed and the stored energies are 6.5 kJ for sol.1. | Zheng Shijun Yang Tongjun Wu Wei Chen Yuquan Wu Beimin Mei Enming | 2019 | IMP & HIRFL Annual Report2019，，1： | 0 |
| 20 | Phase reaction of Au/Sn solder bonding for GaN-based vertical structure light emitting diodes显示文摘Au/Sn solder bonding on Si substrates was used to fabricate the GaN-based vertical structure light emitting diodes (VSLEDs). The phase reaction of Au/Sn solder under different bonding conditions was investigated by the measurement of electron back scattering diffraction (EBSD), and the characteristics of VSLED were analyzed by scanning acoustic microscope (SAM), Raman scattering, current-voltage (I-V) and light output-current (L-I) curves. After the bonding process, horizontal stripes of Au/Sn phase (δ phase) and Au5Sn phase (ζ phase) were redirected to vertical stripes, and δ phase tended to move to the solder joint. Sn interstitial diffusion led to the distribution of δ phase and voids in Au/Sn solder, which could be seen in SAM and SEM images. Vertical distribution of the δ phase and ζ phase with proper voids in the Au/Sn bonding layer showed the best bonding quality. Good bonding quality led to little shift of the E2-high mode of Raman spectra peak in GaN after laser lift off (LLO). It also caused more light extraction and forward bias reduction to 2.9 V at 20 mA. | TIAN PengFei, SUN YongJian, CHEN ZhiZhong, QI ShengLi, DENG JunJing, YU TongJun, QIN ZhiXin & ZHANG GuoYi State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China | 2010 | Science China(Technological Sciences)2010，53，2： | 0 |
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