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Learning to represent 2D human face with mathematical model
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作者 Liping Zhang Weijun Li +3 位作者 Linjun Sun Lina Yu Xin Ning Xiaoli Dong 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第1期54-68,共15页
How to represent a human face pattern?While it is presented in a continuous way in human visual system,computers often store and process it in a discrete manner with 2D arrays of pixels.The authors attempt to learn a ... How to represent a human face pattern?While it is presented in a continuous way in human visual system,computers often store and process it in a discrete manner with 2D arrays of pixels.The authors attempt to learn a continuous surface representation for face image with explicit function.First,an explicit model(EmFace)for human face representation is pro-posed in the form of a finite sum of mathematical terms,where each term is an analytic function element.Further,to estimate the unknown parameters of EmFace,a novel neural network,EmNet,is designed with an encoder-decoder structure and trained from massive face images,where the encoder is defined by a deep convolutional neural network and the decoder is an explicit mathematical expression of EmFace.The authors demonstrate that our EmFace represents face image more accurate than the comparison method,with an average mean square error of 0.000888,0.000936,0.000953 on LFW,IARPA Janus Benchmark-B,and IJB-C datasets.Visualisation results show that,EmFace has a higher representation performance on faces with various expressions,postures,and other factors.Furthermore,EmFace achieves reasonable performance on several face image processing tasks,including face image restoration,denoising,and transformation. 展开更多
关键词 artificial neural networks face analysis image processing mathematics computing
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Editorial's note: The Opportunity and Challenge Faced by Molecular Medicine
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《Journal of Reproduction and Contraception》 CAS 2002年第2期116-116,共1页
Since 1980’s,life science has been holding a prominent place in the development ofscience and it is expected to become one of the leading disciplines in the 21 century.Currently the development of life science presen... Since 1980’s,life science has been holding a prominent place in the development ofscience and it is expected to become one of the leading disciplines in the 21 century.Currently the development of life science presents the following characteristics:1.The understanding of life was deepened to the molecule level. 展开更多
关键词 the Opportunity and Challenge faced by Molecular Medicine Editorial’s note
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The Even-Odd and the Isoelectronicity Rules Applied to Single Covalent Bonds in Ionic, Double-Face-Centered Cubic and Diamond-Like Crystals 被引量:6
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作者 Geoffroy Auvert Marine Auvert 《Open Journal of Physical Chemistry》 2016年第2期21-33,共13页
Although atom configuration in crystals is precisely known thanks to imaging techniques, there is no experimental way to know the exact location of bonds or charges. Many different representations have been proposed, ... Although atom configuration in crystals is precisely known thanks to imaging techniques, there is no experimental way to know the exact location of bonds or charges. Many different representations have been proposed, yet no theory to unify conceptions. The present paper describes methods to derive bonds and charge location in double-face-centered cubic crystals with 4 and 6 atoms per unit cell using two novel rules introduced in earlier works: the even-odd and the isoelectronicity rules. Both of these rules were previously applied to ions, molecules and some solids, and the even-odd rule was also tested on two covalent crystal structures: centered-cubic and single-face-centered cubic crystals. In the present study, the diamond-like structure was subjected to the isoelectronicity rule in order to derive Zinc-blende structures. Rock-salt-like crystals were derived from each other using both rules. These structures represent together more than 230 different crystals. Findings for these structures are threefold: both rules describe a very sure method to obtain valid single covalent-bonded structures;single covalent structures can be used in every case instead of the classical ionic model;covalent bonds and charges positions do not have any relation with the valence number given in the periodic table. 展开更多
关键词 Covalent Bond Even-Odd RULE Single Bond Chemical Structure CRYSTAL Solid Ionic Crystal face-Centered Crystal DIAMOND-LIKE
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An analytical solution for evaluating the safety of an exposed face in a paste backfill stope incorporating the arching phenomenon 被引量:11
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作者 Xu Zhao Andy Fourie Chong-chong Qi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第10期1206-1216,共11页
In current underground mining, the stability of the exposed backfill face is a basic issue associated with mining design and has been the subject of considerable research in mining safety and efficiency. In this study... In current underground mining, the stability of the exposed backfill face is a basic issue associated with mining design and has been the subject of considerable research in mining safety and efficiency. In this study, an improved analytical solution for evaluating the safety of vertically exposed faces in backfilling was proposed. Based on a differential slice method, the proposed solution emphasizes the arching effect as having the advantages of more rigor and wider scalability. Feasibility of the proposed solution was validated with classic centrifuge results. Good agreement between compared results indicated that the proposed solution skillfully predicts the behavior of the paste centrifuge model. Additionally, calculation of exposed face safety in sequential filling was presented. The proposed solution has practical significance in mine backfill design. 展开更多
关键词 mine SAFETY cemented PASTE BACKFILL EXPOSED face ARCHING sequential filling
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Comparison of perceived pain and patients’ satisfaction with traditional local anesthesia and single tooth anesthesia: A randomized clinical trial 被引量:8
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作者 Mohammad I Al-Obaida Mehdiya Haider +4 位作者 Rawan Hashim Wafa AlGheriri Sree Lalita Celur Samar A Al-Saleh Ebtissam M Al-Madi 《World Journal of Clinical Cases》 SCIE 2019年第19期2986-2994,共9页
BACKGROUND Contemporary innovations in the area of local anesthesia have attempted to provide an absolutely pain free experience for patients.Since the introduction of Computer-Controlled Local Anesthetic Delivery Sys... BACKGROUND Contemporary innovations in the area of local anesthesia have attempted to provide an absolutely pain free experience for patients.Since the introduction of Computer-Controlled Local Anesthetic Delivery Systems to dentistry,many studies have compared its efficacy and safety to conventional anesthesia.However,very few studies have compared single tooth anesthesia(STA)and traditional local anesthesia.AIM To compare pain rating,changes in blood pressure,and heart rate during the local anesthetic injection.The secondary objectives were to measure the patients’level of satisfaction and the differences in anesthetic efficiency between the STA system and traditional local infiltration.METHODS A randomized controlled trial was conducted and a total of 80 patients with dental restorative needs were enrolled for the study.The patients were evaluated for their general physical status and oral clinical findings before enrollment.Information regarding perceived pain,changes in heart rate and blood pressure,and patients’satisfaction was collected using an electronic data form and was analyzed using paired and unpaired t-tests.RESULTS No significant difference was noted in perceived pain(P=0.59)and systolic blood pressure(P=0.09)during anesthetic injection using both traditional and STA techniques.STA patients had a significantly higher heart rate during anesthesia,although a statistically significant difference was noted among the traditional anesthesia and the STA groups even before anesthesia.During the restorative procedure,less pain was perceived by STA patients on the Wong-Baker FACES pain scale,which was statistically significant(P<0.001).Analyses of post-procedure patient responses showed that STA patients had a significantly better treatment experience and preferred to have the same method of injection in the future(P=0.04).CONCLUSION STA system can provide less painful and more comfortable restorative treatment procedures in comparison to the traditional infiltration technique. 展开更多
关键词 Local ANEStheSIA Single tooth ANEStheSIA PAIN experience Patient SATISFACTION Pulse rate Heart BEAT Wong-Baker faceS PAIN scale
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Generating animatable 3D cartoon faces from single portraits
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作者 Chuanyu PAN Guowei YANG +1 位作者 Taijiang MU Yu-Kun LAI 《虚拟现实与智能硬件(中英文)》 EI 2024年第4期292-307,共16页
Background With the development of virtual reality(VR)technology,there is a growing need for customized 3D avatars.However,traditional methods for 3D avatar modeling are either time-consuming or fail to retain the sim... Background With the development of virtual reality(VR)technology,there is a growing need for customized 3D avatars.However,traditional methods for 3D avatar modeling are either time-consuming or fail to retain the similarity to the person being modeled.This study presents a novel framework for generating animatable 3D cartoon faces from a single portrait image.Methods First,we transferred an input real-world portrait to a stylized cartoon image using StyleGAN.We then proposed a two-stage reconstruction method to recover a 3D cartoon face with detailed texture.Our two-stage strategy initially performs coarse estimation based on template models and subsequently refines the model by nonrigid deformation under landmark supervision.Finally,we proposed a semantic-preserving face-rigging method based on manually created templates and deformation transfer.Conclusions Compared with prior arts,the qualitative and quantitative results show that our method achieves better accuracy,aesthetics,and similarity criteria.Furthermore,we demonstrated the capability of the proposed 3D model for real-time facial animation. 展开更多
关键词 3D reconstruction Cartoon face reconstruction face rigging Stylized reconstruction Virtual reality
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Facial aesthetics is shaped not only by genetic predispositions but also by the cultural norms and values
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作者 Takahiko Nagamine 《World Journal of Clinical Cases》 SCIE 2024年第34期6684-6686,共3页
The positioning of teeth is of significant importance,both in terms of function and aesthetics.Aesthetics is a subjective matter,and there is often a discrepancy between the perceptions of patients and those of medica... The positioning of teeth is of significant importance,both in terms of function and aesthetics.Aesthetics is a subjective matter,and there is often a discrepancy between the perceptions of patients and those of medical professionals.The act of wearing a mask has been demonstrated to impair the ability to evaluate facial attractiveness,thereby reaffirming the visual importance of the oral cavity in the context of facial aesthetics.The notion that a face perceived as beautiful is inherently exceptional is a fallacy.An average face is defined as one that exhibits characteristics that are common to the group.However,cultural mutations occur at a faster rate than genetic mutations.With regard to changes in facial aesthetics,cultural differences have a more immediate effect than genetic mutations.The advent of the internet meme may herald the advent of an era in which the average face that defines a beautiful face is determined by the internet. 展开更多
关键词 ORTHOdoNTICS Mask GENETICS Culture Average face
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The Relation between Mental Workload and Face Temperature in Flight Simulation
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作者 Amin Bonyad Hamdi Ben Abdessalem Claude Frasson 《Journal of Behavioral and Brain Science》 2024年第2期64-92,共29页
In this research, we study the relationship between mental workload and facial temperature of aircraft participants during a simulated takeoff flight. We conducted experiments to comprehend the correlation between wor... In this research, we study the relationship between mental workload and facial temperature of aircraft participants during a simulated takeoff flight. We conducted experiments to comprehend the correlation between work and facial temperature within the flight simulator. The experiment involved a group of 10 participants who played the role of pilots in a simulated A-320 flight. Six different flying scenarios were designed to simulate normal and emergency situations on airplane takeoff that would occur in different levels of mental workload for the participants. The measurements were workload assessment, face temperatures, and heart rate monitoring. Throughout the experiments, we collected a total of 120 instances of takeoffs, together with over 10 hours of time-series data including heart rate, workload, and face thermal images and temperatures. Comparative analysis of EEG data and thermal image types, revealed intriguing findings. The results indicate a notable inverse relationship between workload and facial muscle temperatures, as well as facial landmark points. The results of this study contribute to a deeper understanding of the physiological effects of workload, as well as practical implications for aviation safety and performance. 展开更多
关键词 Mental Workload EEG thermal Images Flight Simulation AVIATION face Temperature
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Investigation on the stress field characteristic of top coal at FMTC faces under the influence of caving thickness 被引量:5
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作者 谢广祥 常聚才 杨科 《Journal of Coal Science & Engineering(China)》 2007年第2期123-125,共3页
In the background of the technology condition and the geological condition of the 1151(3) fully mechanized top-coal caving face (FMTC face), and by means of taking nonlinear 3D numerical simulation, the stress red... In the background of the technology condition and the geological condition of the 1151(3) fully mechanized top-coal caving face (FMTC face), and by means of taking nonlinear 3D numerical simulation, the stress redistribution rules of top coal with different thick coal seam were obtained by investigation on the numerical simulation of the redistributions of the stress with different coal seam's thickness. The research showes that there exists a certain difference on the stress distributions of the top coal at face, the maximum principal stress is located near to the tailentry's corner. The vertical stress's peak of the top coal decreases and the distance ahead of face position increases as the once mining thickness of the coal seam increases. At the same coal seam, the vertical stresses' peak of top coal gradually decreases from the top to the bottom, the peak's position is basically the same and its changes are gradually obvious with the thickness of coal seam increas- ing. The vertical stress of top coal places in a low stress state at a certain range ahead of face and over the face, which reveals the essence that the support loads are generally low under the condition of FMTC. The study supplies the theoretical foundation for the support design and selection, the theory of top coal's fragmentation, the movement rules of top coal and improving the recovery of top coal. 展开更多
关键词 fully mechanized top-coal caving face thickness of coal seam top coal stress field
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Advancing Wound Filling Extraction on 3D Faces:An Auto-Segmentation and Wound Face Regeneration Approach
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作者 Duong Q.Nguyen Thinh D.Le +2 位作者 Phuong D.Nguyen Nga T.K.Le H.Nguyen-Xuan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2197-2214,共18页
Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications.In this paper,we propose an efficient approach for automating 3D facial wound seg... Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications.In this paper,we propose an efficient approach for automating 3D facial wound segmentation using a two-stream graph convolutional network.Our method leverages the Cir3D-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss functions.To achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the trainedmodels.The selectedmodel demonstrates exceptional segmentation performance for complex 3D facial wounds.Furthermore,based on the segmentation model,we propose an improved approach for extracting 3D facial wound fillers and compare it to the results of the previous study.Our method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous method.From this result,we use 3D printing technology to illustrate the shape of the wound filling.The outcomes of this study have significant implications for physicians involved in preoperative planning and intervention design.By automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient outcomes.Additionally,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3D bioprinting for printing skin tissue implants.Our source code is available at https://github.com/SIMOGroup/WoundFilling3D. 展开更多
关键词 3D printing technology face reconstruction 3D segmentation 3D printed model
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Three-dimensional pseudo-dynamic reliability analysis of seismic shield tunnel faces combined with sparse polynomial chaos expansion
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作者 GUO Feng-qi LI Shi-wei ZOU Jin-Feng 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2087-2101,共15页
To address the seismic face stability challenges encountered in urban and subsea tunnel construction,an efficient probabilistic analysis framework for shield tunnel faces under seismic conditions is proposed.Based on ... To address the seismic face stability challenges encountered in urban and subsea tunnel construction,an efficient probabilistic analysis framework for shield tunnel faces under seismic conditions is proposed.Based on the upper-bound theory of limit analysis,an improved three-dimensional discrete deterministic mechanism,accounting for the heterogeneous nature of soil media,is formulated to evaluate seismic face stability.The metamodel of failure probabilistic assessments for seismic tunnel faces is constructed by integrating the sparse polynomial chaos expansion method(SPCE)with the modified pseudo-dynamic approach(MPD).The improved deterministic model is validated by comparing with published literature and numerical simulations results,and the SPCE-MPD metamodel is examined with the traditional MCS method.Based on the SPCE-MPD metamodels,the seismic effects on face failure probability and reliability index are presented and the global sensitivity analysis(GSA)is involved to reflect the influence order of seismic action parameters.Finally,the proposed approach is tested to be effective by a engineering case of the Chengdu outer ring tunnel.The results show that higher uncertainty of seismic response on face stability should be noticed in areas with intense earthquakes and variation of seismic wave velocity has the most profound influence on tunnel face stability. 展开更多
关键词 reliability analysis shield tunnel face sparse polynomial chaos expansion modified pseudo-dynamic approach seismic stability assessment
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Novel Solution Based on Face Recognition to Address Identity Theft and Cheating in Online Examination Systems 被引量:1
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作者 Ayham Fayyoumi Anis Zarrad 《Advances in Internet of Things》 2014年第2期5-12,共8页
The main objective of this research is to provide a solution for online exam systems by using face recognition to authenticate learners for attending an online exam. More importantly, the system continuously (with sho... The main objective of this research is to provide a solution for online exam systems by using face recognition to authenticate learners for attending an online exam. More importantly, the system continuously (with short time intervals), checks for learner identity during the whole exam period to ensure that the learner who started the exam is the same one who continued until the end and prevent the possibility of cheating by looking at adjacent PC or reading from an external paper. The system will issue an early warning to the learners if suspicious behavior has been noticed by the system. The proposed system has been presented to eight e-learning instructors and experts in addition to 32 students to gather feedback and to study the impact and the benefit of such system in e-learning environment. 展开更多
关键词 Online EXAM face Recognition AUtheNTICATION EXAM CHEATING
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Development of a DFN-based probabilistic block theory approach for bench face angle design in open pit mining
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作者 Jianhua Yan Xiansen Xing +4 位作者 Zhihai Li Weida Ni Liuyuan Zhao Chun Zhu Yuanyuan He 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3047-3062,共16页
In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face ... In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable mining.This study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks testing.The proposed approach was applied to a granite mine in China.First,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit slopes.Then,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each sector.Finally,a bench face angle was determined commensurate with an acceptable risk level of stability.The simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities. 展开更多
关键词 Open pit mine Bench face angle Block theory Probabilistic approach Discrete fracture network modeling Fractured rock slope
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High-Speed Time-Domain En Face Optical Coherence Tomography System Using KTN Optical Beam Deflector 被引量:1
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作者 Masato Ohmi Yusuke Shinya +2 位作者 Jun Miyazu Seiji Toyoda Tadashi Sakamoto 《Optics and Photonics Journal》 2019年第5期53-59,共7页
We developed high-speed time-domain (TD) en face optical coherence tomography (OCT) system using KTN optical beam deflector. The KTN optical beam deflector operates at a high repetition rate of 200 kHz with a fairly l... We developed high-speed time-domain (TD) en face optical coherence tomography (OCT) system using KTN optical beam deflector. The KTN optical beam deflector operates at a high repetition rate of 200 kHz with a fairly large beam deflection angle. We proposed a high-speed en face OCT system that used a KTN optical deflector as the sample beam scanning. In the experiment, we obtained en face OCT images of human fingerprint with a frame rate of 800 fps, which is the fastest speed obtained by a TD-OCT imaging. Furthermore, a 3D-OCT image was also obtained at 0.2 s (=5 volumes/s) by our imaging system. 展开更多
关键词 OPTICAL Coherence tomography EN face OCT KTN OPTICAL Beam DEFLECtoR
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Measurement of the surface morphology of plasma facing components on the EAST tokamak by a laser speckle interferometry approach 被引量:1
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作者 Hongbei WANG Xiaoqian CUI +4 位作者 Yuanbo LI Mengge ZHAO Shuhua LI Guangnan LUO Hongbin DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第3期172-178,共7页
The laser speckle interferometry approach provides the possibility of an in situ optical noncontacted measurement for the surface morphology of plasma facing components(PFCs),and the reconstruction image of the PFC su... The laser speckle interferometry approach provides the possibility of an in situ optical noncontacted measurement for the surface morphology of plasma facing components(PFCs),and the reconstruction image of the PFC surface morphology is computed by a numerical model based on a phase unwrapping algorithm.A remote speckle interferometry measurement at a distance of three meters for real divertor tiles retired from EAST was carried out in the laboratory to simulate a real detection condition on EAST.The preliminary surface morphology of the divertor tiles was well reproduced by the reconstructed geometric image.The feasibility and reliability of this approach for the real-time measurement of PFCs have been demonstrated. 展开更多
关键词 plasma facing components laser speckle interferometry morphology measurement
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Influence of mining thickness to the mechanical characteristics of gateways at FMTC faces 被引量:1
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作者 谢广祥 王磊 《Journal of Coal Science & Engineering(China)》 2008年第1期1-5,共5页
To make a better understanding of the mechanical characteristics of the surrounding rocks in the tailentry and headentry with different coal seam thickness at fully mechanized top-coal caving face (FMTC face), the s... To make a better understanding of the mechanical characteristics of the surrounding rocks in the tailentry and headentry with different coal seam thickness at fully mechanized top-coal caving face (FMTC face), the stress transition and displacement around the periphery of the gateways with different coal thicknesses were investigated in details by means of in situ measurement and 3-D numerical simulation. The research shows that the stresses decrease in the two spallings of the headentry and floor at goal with the increase in mining thickness. The roof pressure in the gates does not change obviously with the coal thickness, but the thicker the coal seam is, the farther the maximum stress will apply to the coal rib at the working face. The vertical stress is higher than the horizontal stress at two spallings of the gate, while its horizontal stress is higher than the vertical stress at the roof. The relative displacement between the roof and floor and the two spallings in the gateways increases gradually with the increase in coal seam thickness in a definite range in front of the face. Near the mining face, the stress decreases in the surrounding rock of the gates, while the deformation appears the most intensive. It is proposed that the support concept to the tailentry and headentry should be changed from loading control to deformation control. 展开更多
关键词 FMTC face coal seam thickness GATEWAYS STRESS DISPLACEMENT
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A Comparative Study on the Processing of Emojis and Faces in Human Communication
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作者 TANG Meng-meng SUN Yan-rui 《Journal of Literature and Art Studies》 2024年第8期703-710,共8页
In the digital era,emojis have enriched the way people communicate and research on emojis explosively increased in recent years.However,few noticed their functions from the neurocognitive perspective,especially their ... In the digital era,emojis have enriched the way people communicate and research on emojis explosively increased in recent years.However,few noticed their functions from the neurocognitive perspective,especially their similarities and differences with facial expressions in traditional face-to-face communication.To fill this gap,we conducted a Meta-analysis with 25 independent effect sizes from previous experimental studies.The present study shows that emojis have slight advantages in processing efficiency,which might be attributed to their simplicity in design,namely the omission of complex facial features,but the difference between emoji and face processing is not significant.In addition,emotional valence and experimental methods do not have significant influences,which suggests that emojis are equally effective as human faces in emotional expression.The current research contributes to the knowledge in digital communication and the crucial role played by emojis therein. 展开更多
关键词 emoji processing face processing COMPARISON
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Discourse Analysis Based on Face-Threatening Theory-A Case Study of TucaodahuiⅢ
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作者 ZHOU Qin 《Sino-US English Teaching》 2024年第4期188-193,共6页
Face and politeness are very important parts in people’s daily communication.But people will violate the principle of politeness for protecting their own face.Therefore,they usually choose to use more humorous words ... Face and politeness are very important parts in people’s daily communication.But people will violate the principle of politeness for protecting their own face.Therefore,they usually choose to use more humorous words or jocular words to communicate in order to avoid direct contradictions.Starting from the face-threatening acts in the face theory and politeness principle,this paper briefly analyzes the face-threatening acts and its humorous usage in the TucaodahuiⅢ. 展开更多
关键词 face theory face-threatening acts TucaodahuiⅢ
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Theoretical analysis on the deformation characteristics of coal wall in a longwall top coal caving face 被引量:5
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作者 Bai Qingsheng Tu Shihao +1 位作者 Li Zhaoxin Tu Hongsheng 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第2期199-204,共6页
Against the background of analyzing coal wall stability in 14101 fully mechanized longwall top coal caving face in Majialiang coal mine,based on the torque equilibrium of the coal wall,shield support and the roof stra... Against the background of analyzing coal wall stability in 14101 fully mechanized longwall top coal caving face in Majialiang coal mine,based on the torque equilibrium of the coal wall,shield support and the roof strata,an elastic mechanics model was established to calculate the stress applied on the coal wall.The displacement method was used to obtain the stress and deformation distributions of the coal wall.This study also researched the influence of support resistance,protective pressure to the coal wall,fracture position of the main roof and mining height on the coal wall deformation.The following conclusions are drawn:(1) The shorter the distance from the longwall face,the greater the vertical compressive stress and horizontal tensile stress borne by the coal wall.The coal wall is prone to failure in the form of compressive-shear and tension;(2) With increasing support resistance,the revolution angle of the main roof decreases linearly.As the support resistance and protective force supplied by the face guard increases,the maximum deformation of the coal wall decreases linearly;(3) As the face approaches the fracture position of the main roof,coal wall horizontal deformation increases significantly,and the coal wall is prone to instability;and(4) The best mining height of 14101 longwall face is 3.0 m. 展开更多
关键词 Longwall top coal caving face Coal wall deformation torque equilibrium Displacement method Parametric analysis
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A Framework for Driver DrowsinessMonitoring Using a Convolutional Neural Network and the Internet of Things
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作者 Muhamad Irsan Rosilah Hassan +3 位作者 Anwar Hassan Ibrahim Mohamad Khatim Hasan Meng Chun Lam Wan Mohd Hirwani Wan Hussain 《Intelligent Automation & Soft Computing》 2024年第2期157-174,共18页
One of the major causes of road accidents is sleepy drivers.Such accidents typically result in fatalities and financial losses and disadvantage other road users.Numerous studies have been conducted to identify the dri... One of the major causes of road accidents is sleepy drivers.Such accidents typically result in fatalities and financial losses and disadvantage other road users.Numerous studies have been conducted to identify the driver’s sleepiness and integrate it into a warning system.Most studies have examined how the mouth and eyelids move.However,this limits the system’s ability to identify drowsiness traits.Therefore,this study designed an Accident Detection Framework(RPK)that could be used to reduce road accidents due to sleepiness and detect the location of accidents.The drowsiness detectionmodel used three facial parameters:Yawning,closed eyes(blinking),and an upright head position.This model used a Convolutional Neural Network(CNN)consisting of two phases.The initial phase involves video processing and facial landmark coordinate detection.The second phase involves developing the extraction of frame-based features using normalization methods.All these phases used OpenCV and TensorFlow.The dataset contained 5017 images with 874 open eyes images,850 closed eyes images,723 open-mouth images,725 closed-mouth images,761 sleepy-head images,and 1084 non-sleepy head images.The dataset of 5017 images was divided into the training set with 4505 images and the testing set with 512 images,with a ratio of 90:10.The results showed that the RPK design could detect sleepiness by using deep learning techniques with high accuracy on all three parameters;namely 98%for eye blinking,96%for mouth yawning,and 97%for head movement.Overall,the test results have provided an overview of how the developed RPK prototype can accurately identify drowsy drivers.These findings will have a significant impact on the improvement of road users’safety and mobility. 展开更多
关键词 Drowsy drivers convolutional neural network OPENCV MICROPROCESSOR face detection
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