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Enhancing force sensing in a squeezed optomechanical system with quantum nondemolition measurement

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Communications in Theoretical Physics 2024年第1期76卷 49-60页

作者： shi-Lei Chao Zi-Hao Li Xin-you Lü School of Physics Huazhong University of Science and Technology430074 WuhanChina

A theoretical scheme is proposed to enhance the sensitivity of force sensors with quantum nondemolition measurement(QND)in an optomechanical setup assisted by four-tone optical driving and an optical parametric amplifier(OPA).With the help of special drive,the system can be simplified as the typical type of QND for force sensing,so that the backaction noise can be evaded to surpass the standard quantum limit.Besides,the added noise can be suppressed owing to the modified optical susceptibility resulting from the OPA.By introducing two oscillators coupling with two charged bodies respectively,the signal can be enhanced with the nonlinearity caused by Coulomb interaction,while the noise presents an exponential decrease.Moreover,considering the homodyne detection effect,the range of system parameters and frequency bands will be broadened.The present investigation may provide a route toward simultaneously evading backaction noise,reducing the mechanical thermal noise,and enhancing the external signal,which can be an alternative design for sensitive devices.

关键词： force sensing optical parametric amplifier quantum non-demolition measurement optomechanical system

Surface demineralized freeze-dried bone allograft followed by reimplantation in a failed mandibular dental implant

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Regenerative Biomaterials 2024年第1期3卷 82-93页

作者： Jing Zhang jie Wang Jiayi you Xuan Qin Huimin Chen Xiantong Hu Yantao Zhao Yang Xia Jiangsu Key Laboratory of Oral Diseases Nanjing Medical UniversityNanjingJiangsu 210029PR China Jiangsu Province Engineering Research Center of Stomatological Translational Medicine Nanjing Medical UniversityNanjingJiangsu 210029PR China Department of Restorative Dental Sciences Faculty of DentistryThe University of Hong KongHong Kong SARPR China Senior Department of Orthopedics The Fourth Medical Center of PLA General HospitalBeijing100048PR China Beijing Engineering Research Center of Orthopedics Implants Beijing 100048PR China State Key Laboratory of Military Stomatology Xi'an 710032PR China

The removal of a failed implant with high torque causes significant damage to the surrounding tissue,compromising bone regeneration and subsequent osseointegration in the defect area.Here,we report a case of carrier screw fracture followed by immediate implant removal,bone grafting and delayed reimplantation.A dental implant with a fractured central carrier screw was removed using the bur-forceps technique.The resulting three-wall bone defect was filled with granular surface demineralized freeze-dried bone allograft(SD-FDBA).Cone-beam computerized tomography was performed at 1week,6months and 15months postoperatively and standardized for quantitative evaluation.The alveolar bone width and height at 15months post-surgery were about 91%of the original values,with a slightly lower bone density,calculated using the gray value ratio.The graft site was reopened and was found to be completely healed with dense and vascularized bone along with some residual bone graft.Reimplantation followed by restoration was performed 8months later.The quality of regenerated bone following SD-FDBA grafting was adequate for osseointegration and longterm implant success.The excellent osteogenic properties of SD-FDBA are attributed to its human origin,cortical bone-like structure,partly demineralized surfaces and bone morphogenetic protein-2-containing nature.Further investigation with more cases and longer follow-up was required to confirm the final clinical effect.

关键词： dental implant implant failure allogeneic bone bone regeneration reimplantation

The Adjustment Analysis Method of the Active Surface Antenna Based on Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第6期24卷 296-308页

作者： you Ban Shang shi Na Wang Qian Xu Shufei Feng School of Mechanical Engineering Xinjiang University Xinjiang Astronomical Observatory Chinese Academy of Sciences School of Mechanical Engineering Dongguan University of Technology

Active surface technique is one of the key technologies to ensure the reflector accuracy of the millimeter/submillimeter wave large reflector antenna. The antenna is complex, large-scale, and high-precision equipment,and its active surfaces are affected by various factors that are difficult to comprehensively deal with. In this paper,based on the advantage of the deep learning method that can be improved through data learning, we propose the active adjustment value analysis method of large reflector antenna based on deep learning. This method constructs a neural network model for antenna active adjustment analysis in view of the fact that a large reflector antenna consists of multiple panels spliced together. Based on the constraint that a single actuator has to support multiple panels(usually 4), an autonomously learned neural network emphasis layer module is designed to enhance the adaptability of the active adjustment neural network model. The classical 8-meter antenna is used as a case study,the actuators have a mean adjustment error of 0.00252 mm, and the corresponding antenna surface error is0.00523 mm. This active adjustment result shows the effectiveness of the method in this paper.

关键词： methods: analytical methods: numerical techniques: radar astronomy telescopes

Research on intelligent search-and-secure technology in accelerator hazardous areas based on machine vision

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Nuclear Science and Techniques 2024年第4期35卷 96-107页

作者： Ying-Lin Ma Yao Wang Hong-Mei shi Hui-jie Zhang School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Prompt radiation emitted during accelerator operation poses a significant health risk,necessitating a thorough search and securing of hazardous areas prior to initiation.Currently,manual sweep methods are employed.However,the limitations of manual sweeps have become increasingly evident with the implementation of large-scale accelerators.By leveraging advancements in machine vision technology,the automatic identification of stranded personnel in controlled areas through camera imagery presents a viable solution for efficient search and security.Given the criticality of personal safety for stranded individuals,search and security processes must be sufficiently reliable.To ensure comprehensive coverage,180°camera groups were strategically positioned on both sides of the accelerator tunnel to eliminate blind spots within the monitoring range.The YOLOV8 network model was modified to enable the detection of small targets,such as hands and feet,as well as larger targets formed by individuals near the cameras.Furthermore,the system incorporates a pedestrian recognition model that detects human body parts,and an information fusion strategy is used to integrate the detected head,hands,and feet with the identified pedestrians as a cohesive unit.This strategy enhanced the capability of the model to identify pedestrians obstructed by equipment,resulting in a notable improvement in the recall rate.Specifically,recall rates of 0.915 and 0.82were obtained for Datasets 1 and 2,respectively.Although there was a slight decrease in accuracy,it aligned with the intended purpose of the search-and-secure software design.Experimental tests conducted within an accelerator tunnel demonstrated the effectiveness of this approach in achieving reliable recognition outcomes.

关键词： Search and secure Machine vision Camera Human body parts recognition Particle accelerator Hazardous area

Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU Zai-ming GENG Bing-zhen WANG shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily dependent.Under some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite interval.If we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

Reduction behavior of iron ore powder by high-volatile coal in thermogravimetric-gas chromatographic and kinetic analysis

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Journal of Iron and Steel Research(International) 2024年第1期31卷 92-107页

作者： Rui-meng shi Qi-yuan Mi Bin Li Xiao shi Chong Zou Jing Guo Han-jie Guo School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina China International Engineering Consulting Corporation Beijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The reduction behavior of iron ore powder by high-volatile coal was investigated,and its kinetic mechanism was clarified.The effect of volatiles in coal on the reduction reaction of iron ore was compared by utilizing a Xinjiang lignite with a high volatile content and its pyrolysis carbon produced by high-temperature pyrolysis to remove volatiles,serving as a reductant.The mass loss and gas composition of the samples during the reduction process were detected using thermo-gravimetric analysis and gas chromatography,and the morphological changes of iron ore powder were observed through scanning electron microscopy.The kinetic parameters of the iron oxide reduction reaction were calculated by the Flynn-Ozawa-Wall method,and the kinetic mechanism of volatile participation in the iron oxide reduction reaction was determined through the Coats-Redfern method.The results indicate that the coupling effect between the high-volatile coal pyrolysis and reduction reactions occurs during the second stage of the entire coupling process,which corresponds to the late stage of coal pyrolysis with a substantial release of H_(2)and CO.The volatiles in coal actively participated in the reduction reaction,reducing the initiation temperature of the reaction by around 200℃.The reduction of iron oxides by high-volatile coal was jointly promoted by the"hydrogen cycle"and"carbon cycle",resulting in a higher reduction extent and metallization rate at the end of the reaction.When high-volatile coal was used as the reductant,the average activation energy for the entire process was 76.5 kJ/mol,a significant decrease compared to the employment of pyrolysis carbon without volatiles as the reductant(1167 kJ/mol).

关键词： Direct reduction High-volatile coal Volatile Kinetics Reduction mechanism

Surgical treatment of an old avulsion fracture of the ischial tuberosity and ischial ramus: A case report

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World Journal of Orthopedics 2024年第1期15卷 94-100页

作者： Zi-Ru Chen shi-jie Liao Fu-Chun Yang Department of Orthopedic Trauma and Hand Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND Avulsion fracture of the ischial tuberosity is a relatively clinically rare type of trauma that is mainly incurred by adolescents during competitive sports activities.According to previous literature,the most commonly involved sports are soccer,sprinting,and gymnastics,in descending order.Dance-induced avulsion fracture of the ischial tuberosity and ischial ramus is extremely clinically rare.CASE SUMMARY A case of a neglected avulsion fracture of the ischial tuberosity and ischial ramus was diagnosed in a young female dancer who complained of pain and restricted movement of her right hip.She stated that she had suffered the injury while performing a split leap during a dance performance 9 mo prior.Eventually,she underwent surgery and obtained satisfactory treatment results.CONCLUSION Early diagnosis of these fractures is important to ensuring early proper treatment towards a quicker recovery.For old fractures with nonunion and chronic buttock pain,surgery is a preferred therapeutic choice with good treatment outcomes.

关键词： Ischial tuberosity Ischial ramus Avulsion fracture Delayed diagnosis Splitleap injury Case report

Migration and transformation of Pb,Cu,and Zn during co-combustion of high-chlorine-alkaline coal and Si/Al dominated coal

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Journal of Environmental Sciences 2024年第7期141卷 26-39页

作者： Jiangze Luo Qiwei Yang Jianqiao Wang Boxiong Shen Zhuozhi Wang Qiqi shi Zhong Zhao Chao Huang jie Xu Tianjin Key Laboratory of Clean Energy and Pollution Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin 300103China School of Chemical Engineering Hebei University of TechnologyTianjin 300103China

Shaerhu(SEH)coal is abundant in Xinjiang,China.The utilization of SEH suffers from severe ash deposition,slagging,and fouling problems due to its high-chlorine-alkaline characteristics.The co-combustion of high-alkaline coal and other type coals containing high Si/Al oxides has been proven to be a simple and effective method that will alleviate ash-related problems,but the risk of heavy metals(HMs)contamination in this process is nonnegligible.Hence,the volatilization rates and chemical speciation of Pb,Cu,and Zn in co-combusting SEH and a high Si/Al oxides coal,i.e.,Yuanbaoshan(YBS)coal were investigated in this study.The results showed that the addition of SEH increased the volatilization rates of Pb,Cu,and Zn during the co-combustion at 800℃from 23.70%,23.97%,and 34.98%to 82.31%,30.01%,and 44.03%,respectively,and promoted the extractable state of Cu and Zn.In addition,the interaction between SEH and YBS inhibited the formation of the Pb residue state.SEM-EDS mapping results showed that compared to Zn and Cu,the signal intensity of Pb was extremely weak in regions where some of the Si and Al signal distributions overlap.The DFT results indicated that the O atoms of the metakaolin(Al_(2)O_(3)·2SiO_(2))(001)surface were better bound to the Zn and Cu than Pb atoms after adsorption of the chlorinated HMs.These results contribute to a better understanding of the effects of high-alkaline coal blending combustion on Pb,Cu,and Zn migration and transformation.

关键词： Heavy metals High-chlorine-alkaline coal Coal blending combustion Density functional theory

M2 macrophage-related molecular subtypes and prognostic index for prostate cancer patients through integrating single-cell and bulk RNA sequencing analysis

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Genes & Diseases 2024年第4期11卷 131-133页

作者： Dechao Feng Xu shi Dengxiong Li Ruicheng Wu jie Wang Wuran Wei Ping Han Department of Urology Institute of UrologyWest China HospitalSichuan UniversityChengduSichuan 610041China

Prostate cancer(PCa)is considered as an age-related disease and accounts for the most prevalence of urinary malignancies in men.1 We previously analyzed the cellular landscape of tumor microenvironment in PCa patients,where we found that cancer-related fibroblasts might play an important role in tumorigenesis and the development of PCa and tumor-associated macrophage(TAM)could function synergistically with them.2 Thus,we further integrated single-cell and bulk RNA sequencing with meta-analysis to specify the prognostic effect of TAM on PCa and construct molecular subgroups and predictive index to guide clinical practice.

关键词： patients macrophage cancer