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Assessment of Wet Season Precipitation in the Central United States by the Regional Climate Simulation of the WRFG Member in NARCCAP and Its Relationship with Large-Scale Circulation Biases 被引量:1
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作者 Yating ZHAO Ming XUE +2 位作者 Jing JIANG Xiao-Ming HU Anning HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期619-638,共20页
Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss pos... Assessment of past-climate simulations of regional climate models(RCMs)is important for understanding the reliability of RCMs when used to project future regional climate.Here,we assess the performance and discuss possible causes of biases in a WRF-based RCM with a grid spacing of 50 km,named WRFG,from the North American Regional Climate Change Assessment Program(NARCCAP)in simulating wet season precipitation over the Central United States for a period when observational data are available.The RCM reproduces key features of the precipitation distribution characteristics during late spring to early summer,although it tends to underestimate the magnitude of precipitation.This dry bias is partially due to the model’s lack of skill in simulating nocturnal precipitation related to the lack of eastward propagating convective systems in the simulation.Inaccuracy in reproducing large-scale circulation and environmental conditions is another contributing factor.The too weak simulated pressure gradient between the Rocky Mountains and the Gulf of Mexico results in weaker southerly winds in between,leading to a reduction of warm moist air transport from the Gulf to the Central Great Plains.The simulated low-level horizontal convergence fields are less favorable for upward motion than in the NARR and hence,for the development of moist convection as well.Therefore,a careful examination of an RCM’s deficiencies and the identification of the source of errors are important when using the RCM to project precipitation changes in future climate scenarios. 展开更多
关键词 NARCCAP Central United states PRECIPITATION low-level jet large-scale environment diurnal variation
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Pixelated non-volatile programmable photonic integrated circuits with 20-level intermediate states 被引量:1
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作者 Wenyu Chen Shiyuan Liu Jinlong Zhu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期477-487,共11页
Multi-level programmable photonic integrated circuits(PICs)and optical metasurfaces have gained widespread attention in many fields,such as neuromorphic photonics,opticalcommunications,and quantum information.In this ... Multi-level programmable photonic integrated circuits(PICs)and optical metasurfaces have gained widespread attention in many fields,such as neuromorphic photonics,opticalcommunications,and quantum information.In this paper,we propose pixelated programmable Si_(3)N_(4)PICs with record-high 20-level intermediate states at 785 nm wavelength.Such flexibility in phase or amplitude modulation is achieved by a programmable Sb_(2)S_(3)matrix,the footprint of whose elements can be as small as 1.2μm,limited only by the optical diffraction limit of anin-house developed pulsed laser writing system.We believe our work lays the foundation for laser-writing ultra-high-level(20 levels and even more)programmable photonic systems and metasurfaces based on phase change materials,which could catalyze diverse applications such as programmable neuromorphic photonics,biosensing,optical computing,photonic quantum computing,and reconfigurable metasurfaces. 展开更多
关键词 programmable photonic integrated circuits phase change materials multi-level intermediate states metasurfaces
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Modeling time-dependent mechanical behavior of hard rock considering excavation-induced damage and complex 3D stress states 被引量:1
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作者 Peiyang Yu Xiuli Ding +3 位作者 Peng-Zhi Pan Shuting Miao Zhaofeng Wang Shuling Huang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4046-4065,共20页
To investigate the long-term stability of deep rocks,a three-dimensional(3D)time-dependent model that accounts for excavation-induced damage and complex stress state is developed.This model comprises three main compon... To investigate the long-term stability of deep rocks,a three-dimensional(3D)time-dependent model that accounts for excavation-induced damage and complex stress state is developed.This model comprises three main components:a 3D viscoplastic isotropic constitutive relation that considers excavation damage and complex stress state,a quantitative relationship between critical irreversible deformation and complex stress state,and evolution characteristics of strength parameters.The proposed model is implemented in a self-developed numerical code,i.e.CASRock.The reliability of the model is validated through experiments.It is indicated that the time-dependent fracturing potential index(xTFPI)at a given time during the attenuation creep stage shows a negative correlation with the extent of excavationinduced damage.The time-dependent fracturing process of rock demonstrates a distinct interval effect of the intermediate principal stress,thereby highlighting the 3D stress-dependent characteristic of the model.Finally,the influence of excavation-induced damage and intermediate principal stress on the time-dependent fracturing characteristics of the surrounding rocks around the tunnel is discussed. 展开更多
关键词 Hard rock Excavation damage Complex stress state Three-dimensional(3D)time-dependent model
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Travel-Limiting Disabilities in the United States: Why Accessibility Matters?
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作者 Oluwaseun Ibukun Bhuiyan Alam 《Journal of Transportation Technologies》 2024年第3期336-357,共22页
This study evaluates the distribution of travel-limiting disabilities across genders and geographic locations in the United States. This study aims to describe and compare the socioeconomic and demographic variables o... This study evaluates the distribution of travel-limiting disabilities across genders and geographic locations in the United States. This study aims to describe and compare the socioeconomic and demographic variables of the people with and without travel-limiting disabilities across geographic locations and gender. The study further evaluates the trip purpose and impact of Covid-19 fourth wave pandemic on the use of public transit and travel to physical workplace for the people with and without travel-limiting disabilities across gender and geographic locations. The study uses the 2022 weighted National Household Travel Survey dataset and employs descriptive statistics. Results reaffirm the findings from previous literature that there are more people with travel-limiting disabilities in urban areas and among women. Over 50 percent of people aged 65 and above have a form of travel-limiting disabilities. The most trip for people with travel-limiting disabilities is made for shopping and medical purposes. Across all categories, rural areas, urban areas, male and female for the people without travel-limiting disabilities, COVID-19 fourth wave did not change the pattern of trips made to physical workplace as pre-COVID-19 era. This pattern is also observable for the people with travel-limiting disabilities in rural and urban areas. Females with travel-limiting disabilities reported making less trips to physical workplaces while male reported doing the same as before COVID-19 era. The study concludes that the quantification of travel-limiting disabilities across geographic location and gender is vital in disability study and could drive policy implementation for improved accessibility for the vulnerable population. 展开更多
关键词 national Household Travel Survey United states Travel-Limiting Disabilities Descriptive Statistics Covid-19 Disability Study
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Preparation of entangledW states based on the cavity QED system
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作者 Ke Li Jun-Long Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期290-296,共7页
We present a qubit-loss-free(QLF)fusion scheme for generating large-scale atom W states in cavity quantum electrodynamics(QED)system.Compared to the most current fusion schemes which are conditioned on the case where ... We present a qubit-loss-free(QLF)fusion scheme for generating large-scale atom W states in cavity quantum electrodynamics(QED)system.Compared to the most current fusion schemes which are conditioned on the case where one particle can be extracted from each initial W state to the fusion process,our scheme will access one or two particles from each W state.Based on the atom–cavity-field detuned interaction,three jWin+m+t states can be generated from the jWin,jWim,and jWit states with the help of two auxiliary atoms,and three jWin+m+t+q states can be generated from jWin,jWim,jWit,and a jWiq state with the help of three auxiliary atoms.Comparing the numerical simulations of the resource cost of fusing three small-size W states based on the previous schemes,our fusion scheme seems to be more efficient.This QLF fusion scheme can be generalized to the case of fusing k different or identical particle W states.Furthermore,with no qubit loss,it greatly reduces the number of fusion steps and prepares W states with larger particle numbers. 展开更多
关键词 W state detuned interaction state fusion cavity quantum electrodynamics
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Entropy variances of pure coherent states in the diffusion channel
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作者 Wei-Feng Wu Yong Fang Peng Fu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期384-388,共5页
Using the operator correspondence of the real and fictious modes in the thermo entangled state representation, wesolve the quantum master equation describing the diffusion channel and obtain the Kraus operator-sum rep... Using the operator correspondence of the real and fictious modes in the thermo entangled state representation, wesolve the quantum master equation describing the diffusion channel and obtain the Kraus operator-sum representation ofits analytical solution. we find that the pure coherent states evolve into the new mixed thermal superposed states in thediffusion channel. Also, we investigate the statistical properties of the initial coherent states and their entropy evolutions inthe diffusion channel, and find that the entropy evolutions are only related to the decay time and without the amplitudes ofthe initial coherent states. 展开更多
关键词 entangled state representation diffusion channel coherent state entropy evolution
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Machine-learning-assisted efficient reconstruction of the quantum states generated from the Sagnac polarization-entangled photon source
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作者 毛梦辉 周唯 +3 位作者 李新慧 杨然 龚彦晓 祝世宁 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期50-54,共5页
Neural networks are becoming ubiquitous in various areas of physics as a successful machine learning(ML)technique for addressing different tasks.Based on ML technique,we propose and experimentally demonstrate an effic... Neural networks are becoming ubiquitous in various areas of physics as a successful machine learning(ML)technique for addressing different tasks.Based on ML technique,we propose and experimentally demonstrate an efficient method for state reconstruction of the widely used Sagnac polarization-entangled photon source.By properly modeling the target states,a multi-output fully connected neural network is well trained using only six of the sixteen measurement bases in standard tomography technique,and hence our method reduces the resource consumption without loss of accuracy.We demonstrate the ability of the neural network to predict state parameters with a high precision by using both simulated and experimental data.Explicitly,the mean absolute error for all the parameters is below 0.05 for the simulated data and a mean fidelity of 0.99 is achieved for experimentally generated states.Our method could be generalized to estimate other kinds of states,as well as other quantum information tasks. 展开更多
关键词 machine learning state estimation quantum state tomography polarization-entangled photon source
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Profile of Anemia in Cirrhotic Patients at the National Hospital of Niamey
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作者 Fanta Ousseini Badé Malam Abdou +7 位作者 Amadou Djibrilla Almoustapha Rekiatou Ali Cheik Illa Hamidine Lawagoulé Joseph Emile Ky Ben Moctar Abdou Djibo Nafissatou Abdou Boubé Abdou Gloria Vidinhessi-Tona 《Open Journal of Gastroenterology》 CAS 2024年第10期340-347,共8页
Objective: To study the profile of anemia in cirrhotic patients diagnosed in the Hepato-Gastroenterology (HGE) department of the National Hospital of Niamey. Patients and Method: This was a prospective and descriptive... Objective: To study the profile of anemia in cirrhotic patients diagnosed in the Hepato-Gastroenterology (HGE) department of the National Hospital of Niamey. Patients and Method: This was a prospective and descriptive study carried out from August 1, 2023 to February 29, 2024, including cirrhotic patients, with anemia on the blood count, outside of any recent blood transfusion and/or treatment. History of anemia. Results: The diagnosis of anemia was made in 91 patients out of the 100 cirrhotics recorded, 91%. Men were more common, with a sex ratio of 2.79. The average age was 50 ± 14.22 years old. Anemia was moderate in 52.75% of cases (n = 48). It was non-microcytic in 50.55% (n = 46) and iron deficient in 55.56% of cases (n = 20). There was a statistically significant correlation between the severity of anemia and upper gastrointestinal bleeding with a p-value = 0.000. Conclusion: Cirrhotic anemia is multifactorial, which makes its etiological diagnosis complex. 展开更多
关键词 ANEMIA CIRRHOSIS national Hospital of Niamey NIGER
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Liver Transplantation Outcomes of HBV-,HCV-,and Alcohol-induced Hepatocellular Carcinoma in the United States:Analysis of National Inpatient Samples
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作者 Si-si ZHANG Jin-feng ZHANG +4 位作者 Jing-qiong WANG Jing TANG Zi-long WU Jing HUANG Jun XUE 《Current Medical Science》 SCIE CAS 2023年第3期520-525,共6页
Objective Liver transplantation is a current treatment option for hepatocellular carcinoma(HCC).The United States National Inpatient Sample database was utilized to identify risk factors that influence the outcome of ... Objective Liver transplantation is a current treatment option for hepatocellular carcinoma(HCC).The United States National Inpatient Sample database was utilized to identify risk factors that influence the outcome of liver transplantation,including locoregional recurrence,distant metastasis,and in-hospital mortality,in HCC patients with concurrent hepatitis B infection,hepatitis C infection,or alcoholic cirrhosis.Methods This retrospective cohort study included HCC patients(n=2391)from the National Inpatient Sample database who underwent liver transplantation and were diagnosed with hepatitis B or C virus infection,co-infection with hepatitis B and C,or alcoholic cirrhosis of the liver between 2005 and 2014.Associations between HCC etiology and post-transplant outcomes were examined with multivariate analysis models.Results Liver cirrhosis was due to alcohol in 10.5%of patients,hepatitis B in 6.6%,hepatitis C in 10.8%,and combined hepatitis B and C infection in 24.3%.Distant metastasis was found in 16.7%of patients infected with hepatitis B and 9%of hepatitis C patients.Local recurrence of HCC was significantly more likely to occur in patients with hepatitis B than in those with alcohol-induced disease.Conclusion After liver transplantation,patients with hepatitis B infection have a higher risk of local recurrence and distant metastasis.Postoperative care and patient tracking are essential for liver transplant patients with hepatitis B infection. 展开更多
关键词 alcoholic hepatitis hepatocellular carcinoma liver cirrhosis national Inpatient Sample(NIS)transplantation viral hepatitis
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Topological edge and corner states of valley photonic crystals with zipper-like boundary conditions
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作者 沈云峰 许孝芳 +2 位作者 孙铭 周文佶 常雅箐 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期480-491,共12页
We present a stable valley photonic crystal(VPC)unit cell with C_(3v)symmetric quasi-ring-shaped dielectric columns and realize its topological phase transition by breaking mirror symmetry.Based on this unit cell stru... We present a stable valley photonic crystal(VPC)unit cell with C_(3v)symmetric quasi-ring-shaped dielectric columns and realize its topological phase transition by breaking mirror symmetry.Based on this unit cell structure,topological edge states(TESs)and topological corner states(TCSs)are realized.We obtain a new type of wave transmission mode based on photonic crystal zipper-like boundaries and apply it to a beam splitter assembled from rectangular photonic crystals(PCs).The constructed beam splitter structure is compact and possesses frequency separation functions.In addition,we construct a box-shaped triangular PC structures with zipper-like boundaries and discover phenomena of TCSs in the corners,comparing its corner states with those formed by other boundaries.Based on this,we explore the regularities of the electric field patterns of TESs and TCSs,explain the connection between the characteristic frequencies and locality of TCSs,which helps better control photons and ensures low power consumption of the system. 展开更多
关键词 valley photonic crystal topological edge states topological corner states higher-order topological insulators topological phase transition
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Empowering neuromorphic computing with topological states
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作者 Faisal Ahmed Zhipei Sun 《Journal of Semiconductors》 EI CAS CSCD 2024年第11期8-9,共2页
In 1980,scientist Klaus von Klitzing discovered the quantum Hall effect[1],a groundbreaking achievement that earned him the Nobel Prize in Physics in 1985.This discovery was a significant milestone in condensed matter... In 1980,scientist Klaus von Klitzing discovered the quantum Hall effect[1],a groundbreaking achievement that earned him the Nobel Prize in Physics in 1985.This discovery was a significant milestone in condensed matter physics,representing the first identification of topological quantum states. 展开更多
关键词 states. TOPOLOGICAL QUANTUM
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Comparative Study of the Socioeconomic Characteristics and Digital Literacy Level of Agricultural Extension Personnel in Imo and Ebonyi States, South-East, Nigeria
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作者 Ogbonnaya Okoro Aja Cyril Chigozie Asiabaka +1 位作者 Anthony Okorie Ani Edna Chioma Matthews-Njoku 《Agricultural Sciences》 2024年第2期230-245,共16页
The study comparatively analysed the socioeconomic characteristics and digital literacy level of Agricultural Extension personnel (AEP) in Ebonyi and Imo States, South-East, Nigeria. The specific objectives were to de... The study comparatively analysed the socioeconomic characteristics and digital literacy level of Agricultural Extension personnel (AEP) in Ebonyi and Imo States, South-East, Nigeria. The specific objectives were to describe the socioeconomic characteristics of agricultural extension personnel in Ebonyi and Imo States, and to ascertain the digital literacy level of AEP in the studied states. Purposive sampling technique was used to select 312 Agricultural Extension personnel (132 from Ebonyi State Agricultural Development Program and 180 from Imo State Agricultural Development Program) for the study. Data were collected through the use of validated and structured questionnaire, and administered through the help of well-trained enumerators. Data were analysed using simple descriptive statistical tools such as percentages mean score, standard deviation and weighted mean. Findings indicated that they were more male in the both States (55.3% and 57.8%) for Ebonyi and Imo State respectively and that the average age of AEP in Ebonyi and Imo States were 44.7 years and 49.2 years respectively. It was further revealed that the majority (77.3% and 82.8%) had B.Sc./HND as their highest academic qualifications, belonged to professional organisations (62.1% and 75%), and were earning an average monthly income of N58,798 and N62,648 for Ebonyi and Imo State respectively. Also, it was revealed that their mean years of service were 12.4 years and 13.4 years for Ebonyi and Imo State respectively. Almost all of them (87.9% and 95.0%) own a smartphone, had access to the internet (80.3% and 90.0%), but do not own a laptop/ipad (82.6% and 72.8%) for Ebon-yi and Imo State respectively. Results further revealed that Agricultural extension personnel in both Ebonyi and Imo State respectively had low digital literacy level ( = 2.41 and 2.32). The study concluded that AEP in Ebonyi and Imo State respectively had similar socioeconomic characteristics and low level of digital literacy. The study recommended that the management of ADPs in both Ebonyi and Imo State should ensure the training of AEP in digital skills to enhance their digital literacy level to enable them use digital technologies in their work. 展开更多
关键词 Agricultural Extension Personnel Digital Literacy Ebonyi State Imo State Socioeconomic Characteristics
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Summary Analysis of National Surveillance on Kashin-Beck Disease from 1990 to 2023
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作者 Silu Cui Hui Liu +6 位作者 Junrui Pei Jiaxin Li Zhe Jiao Qing Deng Ning Liu Yanhong Cao Jun Yu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第9期1056-1066,共11页
Objective To analyze the epidemiological characteristics and epidemic situation of children with Kashin-Beck disease(KBD)in China,and provide the basis for formulating prevention and control measures.Methods Fixed-poi... Objective To analyze the epidemiological characteristics and epidemic situation of children with Kashin-Beck disease(KBD)in China,and provide the basis for formulating prevention and control measures.Methods Fixed-point monitoring,moving-point monitoring,and full coverage of monitoring were promoted successively from 1990 to 2023.Some children(7-12 years old)underwent clinical and right-hand X-ray examinations every year.According to the KBD diagnosis criteria,clinical and X-ray assessments were used to confirm the diagnosis.Results In 1990,the national KBD detectable rate was 21.01%.X-ray detection decreased to below 10%in 2003 and below 5%in 2007.Between 2010 and 2018,the prevalence of KBD in children was less than 0.4%,which fluctuated at a low level,and has decreased to 0%since 2019.Spatial epidemiological analysis indicated a spatial clustering of adult patients prevalence rate in the KBD areas.Conclusion The evaluation results of the elimination of KBD in China over the last 5 years showed that all villages in the monitored areas have reached the elimination standard.While the adult KBD patients still need for policy consideration and care. 展开更多
关键词 Kashin-Beck disease Geographic Information System national surveillance X-ray detective rate
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Terrain or climate factor dominates vegetation resilience?Evidence from three national parks across different climatic zones in China
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作者 Shuang Liu Lingxin Wu +3 位作者 Shiyong Zhen Qinxian Lin Xisheng Hu Jian Li 《Forest Ecosystems》 SCIE CSCD 2024年第4期526-542,共17页
Vegetation resilience(VR),providing an objective measure of ecosystem health,has received considerable attention,however,there is still limited understanding of whether the dominant factors differ across different cli... Vegetation resilience(VR),providing an objective measure of ecosystem health,has received considerable attention,however,there is still limited understanding of whether the dominant factors differ across different climate zones.We took the three national parks(Hainan Tropical Rainforest National Park,HTR;Wuyishan National Park,WYS;and Northeast Tiger and Leopard National Park,NTL)of China with less human interference as cases,which are distributed in different climatic zones,including tropical,subtropical and temperate monsoon climates,respectively.Then,we employed the probabilistic decay method to explore the spatio-temporal changes in the VR and their natural driving patterns using Geographically Weighted Regression(GWR)model as well.The results revealed that:(1)from 2000 to 2020,the Normalized Difference Vegetation Index(NDVI)of the three national parks fluctuated between 0.800 and 0.960,exhibiting an overall upward trend,with the mean NDVI of NTL(0.923)>HTR(0.899)>WYS(0.823);(2)the positive trend decay time of vegetation exceeded that of negative trend,indicating vegetation gradual recovery of the three national parks since 2012;(3)the VR of HTR was primarily influenced by elevation,aspect,average annual temperature change(AATC),and average annual precipitation change(AAPC);the WYS'VR was mainly affected by elevation,average annual precipitation(AAP),and AAPC;while the terrain factors(elevation and slope)were the main driving factors of VR in NTL;(4)among the main factors influencing the VR changes,the AAPC had the highest proportion in HTR(66.7%),and the AAP occupied the largest area proportion in WYS(80.4%).While in NTL,elevation served as the main driving factor for the VR,encompassing 64.2%of its area.Consequently,our findings indicated that precipitation factors were the main driving force for the VR changes in HTR and WYS national parks,while elevation was the main factors that drove the VR in NTL.Our research has promoted a deeper understanding of the driving mechanism behind the VR. 展开更多
关键词 national parks Vegetation resilience NDVI Probabilistic decay model Driving factors
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Thoroughly Study and Implement a Holistic Approach to National Security to Safeguard Chinese Modernization
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作者 《Contemporary International Relations》 2024年第5期4-25,共22页
2024 marks the tenth anniversary of a holistic approach to national security. As an important component of Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era, a holistic approach to national se... 2024 marks the tenth anniversary of a holistic approach to national security. As an important component of Xi Jinping Thought on Socialism with Chinese Characteristics for a New Era, a holistic approach to national security provides fundamental guidance for China's national security work in the new era and is, therefore, of great theoretical and practical significance. This approach has several distinct features: it ref lects the trends of our times, is deeply rooted in China's national culture, and follows a people-centered, struggle-oriented, systematic, st rategic, in novative, and practice-based approach. By upholding and developing a holistic approach to national security, the Central Committee of the Communist Party of China(CPC) has comprehensively strengthened the Party's absolute leadership over national security, reshaped the systems and mechanisms for national security across the board, and made brilliant achievements in national security work in the new era. Given the context of the momentous changes unseen in a century that shape today's world, the national security situation facing China is increasingly complex and grim, characterized by many challenges and new characteristics. On the new journey toward rejuvenating the nation and building China into a strong country, we should fully implement the spirit of the 20th CPC National Congress, firmly pursue a holistic approach to national security, and accelerate the modernization of China's national security system and capacity to ensure steady and sustained progress in Chinese modernization. 展开更多
关键词 Chinese modernization holistic approach to national security national security situation
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Spectroscopy and molecule opacity investigation on excited states of SiS
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作者 李瑞 吕浩男 +3 位作者 桑纪群 刘晓华 梁桂颖 吴勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期381-387,共7页
The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many years.Due to complex interactions among its low-lying electronic states,precise information regarding the molec... The SiS molecule,which plays a significant role in space,has attracted a great deal of attention for many years.Due to complex interactions among its low-lying electronic states,precise information regarding the molecular structure of SiS is limited.To obtain accurate information about the structure of its excited states,the high-precision multireference configuration interaction(MRCI)method has been utilized.This method is used to calculate the potential energy curves(PECs)of the 18Λ–S states corresponding to the lowest dissociation limit of SiS.The core–valence correlation effect,Davidson’s correction and the scalar relativistic effect are also included to guarantee the precision of the MRCI calculation.Based on the calculated PECs,the spectroscopic constants of quasi-bound and bound electronic states are calculated and they are in accordance with previous experimental results.The transition dipole moments(TDMs)and dipole moments(DMs)are determined by the MRCI method.In addition,the abrupt variations of the DMs for the 1^(5)Σ^(+)and 2^(5)Σ^(+)states at the avoided crossing point are attributed to the variation of the electronic configuration.The opacity of SiS at a pressure of 100 atms is presented across a series of temperatures.With increasing temperature,the expanding population of excited states blurs the band boundaries. 展开更多
关键词 SIS OPACITY excited state spectroscopic constant configuration interaction
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Recent progress on valley polarization and valley-polarized topological states in two-dimensional materials
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作者 王斐 张亚玲 +2 位作者 杨文佳 张会生 许小红 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期16-31,共16页
Valleytronics, using valley degree of freedom to encode, process, and store information, may find practical applications in low-power-consumption devices. Recent theoretical and experimental studies have demonstrated ... Valleytronics, using valley degree of freedom to encode, process, and store information, may find practical applications in low-power-consumption devices. Recent theoretical and experimental studies have demonstrated that twodimensional(2D) honeycomb lattice systems with inversion symmetry breaking, such as transition-metal dichalcogenides(TMDs), are ideal candidates for realizing valley polarization. In addition to the optical field, lifting the valley degeneracy of TMDs by introducing magnetism is an efficient way to manipulate the valley degree of freedom. In this paper, we first review the recent progress on valley polarization in various TMD-based systems, including magnetically doped TMDs,intrinsic TMDs with both inversion and time-reversal symmetry broken, and magnetic TMD heterostructures. When topologically nontrivial bands are empowered into valley-polarized systems, valley-polarized topological states, namely valleypolarized quantum anomalous Hall effect can be realized. Therefore, we have also reviewed the theoretical proposals for realizing valley-polarized topological states in 2D honeycomb lattices. Our paper can help readers quickly grasp the latest research developments in this field. 展开更多
关键词 valley polarization valley-polarized topological states two-dimensional material
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Chiral bound states in a staggered array of coupled resonators
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作者 金伍林 李静 +2 位作者 卢竞 龚志瑞 周兰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期124-130,共7页
We study the chiral bound states in a coupled-resonator array with staggered hopping strengths,which interacts with a two-level small atom through a single coupling point or two adjacent ones.In addition to the two ty... We study the chiral bound states in a coupled-resonator array with staggered hopping strengths,which interacts with a two-level small atom through a single coupling point or two adjacent ones.In addition to the two typical bound states found above and below the energy bands,this system presents an extraordinary chiral bound state located within the energy gap.We use the chirality to quantify the breaking of the mirror symmetry.We find that the chirality value undergoes continuous changes by tuning the coupling strengths.The preferred direction of the chirality is controlled not only by the competition between the intracell and the intercell hoppings in the coupled-resonator array,but also by the coherence between the two coupling points.In the case with one coupling point,the chirality values varies monotonously with difference between the intracell hopping and the intercell hoppings.While in the case with two coupling points,due to the coherence between the two coupling points the perfect chiral states can be obtained. 展开更多
关键词 bound states two-level small atom coupled-resonator array CHIRALITY
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Theoretical investigation of excited dipole bound states of alkali-containing diatomic anions
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作者 连艺 肖利丹 +2 位作者 边丽丽 徐海峰 闫冰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期389-393,共5页
Information about electronic excited states of molecular anions plays an important role in investigating electron attachment and detachment processes.Here we present a high-level theoretical study of the electronic st... Information about electronic excited states of molecular anions plays an important role in investigating electron attachment and detachment processes.Here we present a high-level theoretical study of the electronic structures of 12 alkali-metal-containing diatomic anions MX-(MX = LiH,LiF,LiCl,NaF,NaCl,NaBr,RbCl,KCl,KBr,RbI,KI and CsI).The equation-of-motion electron-attachment coupled-cluster singles and doubles(EOM-EA-CCSD) method is used to calculate the electron binding energies(EBEs) of 10 electronic excited states of each of the 12 molecule anions.With addition of different s-/p-/d-type diffusion functions in the basis set,we have identified possible excited dipole bound states(DBSs) of each anion.With the investigation of EBEs on the 12 MXs with dipole moment(DM) up to 12.1 D,we evaluate the dependence of the number of anionic excited DBSs on molecular DM.The results indicate that there are at least two or three DBSs of anions with a molecular DM larger than 7 D and a molecule with DM > 10 D can sustain a π-DBS of the anion.Our study has some implications for the excited DBS electronic states of alkali-metal-containing diatomic molecules. 展开更多
关键词 ANIONS dipole bound states alkali-metal-containing diatomic molecules
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Characterisation of Human-Wildlife Conflicts around the Kahuzi-Biega National Park, Eastern Democratic Republic of Congo
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作者 Basubi Muke Matthieu Vwima Stany +3 位作者 Ayagirwe Basengere Rodrigue Mushagalusa Freddy Benjamin-Fink Nicole Bobo Kadiri Serge 《Journal of Environmental Protection》 2024年第3期343-356,共14页
The history of mankind contains so many illustrations of well-classified and violent struggles against various animals over crop production in agricultural fields, attacks on human life or competition in order to have... The history of mankind contains so many illustrations of well-classified and violent struggles against various animals over crop production in agricultural fields, attacks on human life or competition in order to have access to certain natural resources. The aim of this study is to characterise the human-wildlife conflicts that occur around the KBNP, especially with regard to primates. Surveys were carried out in 260 households selected using the snowball method. The results showed that human-wildlife conflicts around the KBNP are characterised by the destruction of crops in riparian fields by monkeys, chimpanzees and gorillas, the destruction of houses, physical attacks and zoonoses. Despite the conservation and protection measures for wildlife and local populations put in place by the Park’s managers, conflicts between local populations and the Park’s wild animals are still visible. These conflicts lead to the detention of wild animals by local people roaming in the villages and to poaching on the Park’s boundaries. The weakness of the community management policy on the part of the park managers and the resentment of the indigenous peoples towards the restriction of their access to natural resources are the major constraints on the sustainable management of conflicts between the local populations and the wild animals in the KBNP. The strategies for the sustainable resolution of human-wildlife conflicts around the KBNP must be geared towards and integrated into a community conservation approach. 展开更多
关键词 Community Conservation Human-Wildlife Conflict Kahuzi-Biega national Park
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