期刊文献+
共找到16篇文章
< 1 >
每页显示 20 50 100
Quantization of Action for Elementary Particles and the Principle of Least Action
1
作者 Shuming Wen 《Journal of Modern Physics》 2024年第9期1430-1447,共18页
The uncertainty principle is a fundamental principle of quantum mechanics, but its exact mathematical expression cannot obtain correct results when used to solve theoretical problems such as the energy levels of hydro... The uncertainty principle is a fundamental principle of quantum mechanics, but its exact mathematical expression cannot obtain correct results when used to solve theoretical problems such as the energy levels of hydrogen atoms, one-dimensional deep potential wells, one-dimensional harmonic oscillators, and double-slit experiments. Even after approximate treatment, the results obtained are not completely consistent with those obtained by solving Schrödinger’s equation. This indicates that further research on the uncertainty principle is necessary. Therefore, using the de Broglie matter wave hypothesis, we quantize the action of an elementary particle in natural coordinates and obtain the quantization condition and a new deterministic relation. Using this quantization condition, we obtain the energy level formulas of an elementary particle in different conditions in a classical way that is completely consistent with the results obtained by solving Schrödinger’s equation. A new physical interpretation is given for the particle eigenfunction independence of probability for an elementary particle: an elementary particle is in a particle state at the space-time point where the action is quantized, and in a wave state in the rest of the space-time region. The space-time points of particle nature and the wave regions of particle motion constitute the continuous trajectory of particle motion. When an elementary particle is in a particle state, it is localized, whereas in the wave state region, it is nonlocalized. 展开更多
关键词 Elementary Particle Quantization of Action Deterministic Relation Inherent State Nonprobabilistic Interpretation localization region Nonlocalization region
下载PDF
Combining local regional therapy and systemic therapy:Expected changes in the treatment landscape of recurrent hepatocellular carcinoma
2
作者 Jing Liang Yi Bai +3 位作者 Fu-Shuang Ha Ying Luo Hui-Ting Deng Ying-Tang Gao 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第1期1-18,共18页
Improvements in early screening,new diagnostic techniques,and surgical treatment have led to continuous downward trends in hepatocellular carcinoma(HCC)morbidity and mortality rates.However,high recurrence and refract... Improvements in early screening,new diagnostic techniques,and surgical treatment have led to continuous downward trends in hepatocellular carcinoma(HCC)morbidity and mortality rates.However,high recurrence and refractory cancer after hepatectomy remain important factors affecting the long-term prognosis of HCC.The clinical characteristics and prognosis of recurrent HCC are heterogeneous,and guidelines on treatment strategies for recurrent HCC are lacking.Therapies such as surgical resection,radiofrequency ablation,and transhepatic arterial chemoembolization are effective for tumors confined to the liver,and targeted therapy is a very important treatment for unresectable recurrent HCC with systemic metastasis.With the deepening of the understanding of the immune microenvironment of HCC,blocking immune checkpoints to enhance the antitumor immune response has become a new direction for the treatment of HCC.In addition,improvements in the tumor immune microenvironment caused by local treatment may provide an opportunity to improve the therapeutic effect of HCC treatment.Ongoing and future clinical trial data of combined therapy may develop the new treatment scheme for recurrent HCC.This paper reviews the pattern of recurrent HCC and the characteristics of the immune microenvironment,demonstrates the basis for combining local treatment and systemic treatment,and reports current evidence to better understand current progress and future approaches in the treatment of recurrent HCC. 展开更多
关键词 Recurrent hepatocellular carcinoma Local regional therapy Systemic therapy Tumor microenvironment Recurrence type Immune checkpoint inhibitors
下载PDF
Distributed Localization Algorithm for Wireless Sensor Network Based on Multidimensional Scaling and the Shortest Path Distance Correction 被引量:2
3
作者 丁英强 杜留锋 +1 位作者 杨挺 孙雨耕 《Transactions of Tianjin University》 EI CAS 2009年第4期237-244,共8页
Sensor localization is crucial for the configuration and applications of wireless sensor network (WSN). A novel distributed localization algorithm, MDS-DC was proposed for wireless sensor network based on multidimensi... Sensor localization is crucial for the configuration and applications of wireless sensor network (WSN). A novel distributed localization algorithm, MDS-DC was proposed for wireless sensor network based on multidimensional scaling (MDS) and the shortest path distance correction. In MDS-DC, several local positioning regions with reasonable distribution were firstly constructed by an adaptive search algorithm, which ensures the mergence between the local relative maps of the adjacent local position regions and can reduce the number of common nodes in the network. Then, based on the relationships between the estimated distances and actual distances of anchors, the distance estimation vectors of sensors around anchors were corrected in each local positioning region. During the computations of the local relative coordinates, an iterative process, which is the combination of classical MDS algorithm and SMACOF algorithm, was applied. Finally, the global relative positions or absolute positions of sensors were obtained through merging the relative maps of all local positioning regions. Simulation results show that MDS-DC has better performances in positioning precision, energy efficiency and robustness to range error, which can meet the requirements of applications for sensor localization in WSN. 展开更多
关键词 wireless sensor network (WSN) multidimensional scaling local positioning region relative coordinates
下载PDF
A Local Region Molecular Dynamics Simulation Method for Nanoscale Sliding Contacts 被引量:1
4
作者 Rui-Ting Tong Geng Liu Tian-Xiang Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第5期119-126,共8页
Computational e ciency and accuracy always conflict with each other in molecular dynamics(MD) simulations. How to enhance the computational e ciency and keep accuracy at the same time is concerned by each correspondin... Computational e ciency and accuracy always conflict with each other in molecular dynamics(MD) simulations. How to enhance the computational e ciency and keep accuracy at the same time is concerned by each corresponding researcher. However, most of the current studies focus on MD algorithms, and if the scale of MD model could be reduced, the algorithms would be more meaningful. A local region molecular dynamics(LRMD) simulation method which can meet these two factors concurrently in nanoscale sliding contacts is developed in this paper. Full MD simulation is used to simulate indentation process before sliding. A criterion called contribution of displacement is presented, which is used to determine the e ective local region in the MD model after indentation. By using the local region, nanoscale sliding contact between a rigid cylindrical tip and an elastic substrate is investigated. Two two?dimensional MD models are presented, and the friction forces from LRMD simulations agree well with that from full MD simulations, which testifies the e ectiveness of the LRMD simulation method for two?dimensional cases. A three?dimensional MD model for sliding contacts is developed then to show the validity of the LRMD simulation method further. Finally, a discussion is carried out by the principles of tribology. In the discussion, two two?dimensional full MD models are used to simulate the nanoscale sliding contact problems. The results indicate that original smaller model will induce higher equivalent scratching depth, and then results in higher friction forces, which will help to explain the mechanism how the LRMD simulation method works. This method can be used to reduce the scale of MD model in large scale simulations, and it will enhance the computational e ciency without losing accuracy during the simula?tion of nanoscale sliding contacts. 展开更多
关键词 Local region molecular dynamics simulation NANOSCALE Sliding contacts Contribution of displacement
下载PDF
On the regional characteristics of cuisine in China 被引量:2
5
作者 Zhang ShulinDepartment of Geography, Chongqing Teachers College, Chongqing 630047, CHINA 《Journal of Geographical Sciences》 SCIE CSCD 1998年第1期95-100,共6页
This paper attempts to study regional differentiation of cuisine in China and set up a rudimentary framework for regional characteristic of cuisine This framework is mainly concerned with regional school of cuisine (o... This paper attempts to study regional differentiation of cuisine in China and set up a rudimentary framework for regional characteristic of cuisine This framework is mainly concerned with regional school of cuisine (or cuisine systems) and regional dishes It also gives them some explanations of the process of the formation 展开更多
关键词 CUISINE regional feature of cuisine regional school of cuisine regional dishes of local distinctive flavor and taste
下载PDF
Women's Cooperatives Contributions to Local Region Economy: Seferihisar Agricultural Cooperative Development Model-Turkey 被引量:1
6
作者 Yasin Barut 《Management Studies》 2017年第2期120-127,共8页
The cooperative movement has played a very important role in the social and economic development of all countries since 19th eentury's second half. Cooperatives provide health, housing, and banking services; they pro... The cooperative movement has played a very important role in the social and economic development of all countries since 19th eentury's second half. Cooperatives provide health, housing, and banking services; they promote education and gender equality; they protect the environment and workers' rights. According to 2014's data, the total number of cooperatives is 79,486 in Turkey, while the total number of partners of cooperatives is approximately 7.8 million. The research's sample group "Hidirlik Agricultural Development Cooperative" was founded by the wife of the Seferihisar's mayor and six women. It has been a subject of curiousity that the contributions of the cooperative have developed the economy of the region since 2010. Therefore, various questions asked to the president and members of the cooperative, and significant results were obtained. In this research "Interview technique" was used. The fact that within the boundaries of local governments, the establishment of "women's cooperatives" and their active management can be supported with 10 basic criteria for the regional and national development can be predicted. These dimensions: ecological balance and sensitivity, the revival of the tourism sector, the mobility of logistics activities, new investments and increase of land value, the increase of women employment, the increase of healthy living standards, increase of competitiveness and trade earnings, the creation of new brands, widespread of the agricultural sector, and the increase of social and educational level of women. The similiar implementation of "Seferihisar Women's Cooperatives Model" in the research is considered form an important enterprenurship model not only in Turkey but also for all countries. 展开更多
关键词 women's cooperative local region economics women's enterprenurship enterprenurship model
下载PDF
Analysis of the Difference of the Basic Pension by Regions
7
作者 Ye Hanxiong, Wu Xiangling School of Political Science and Public Management, Wuhan University, Wuhan Hubei 430072, China 《Chinese Journal of Population,Resources and Environment》 北大核心 2007年第2期84-87,共4页
Nowadays, the disparity of the basic pension in local regions of China can be described as follows: the low level of the unification of the basic pension systems, the large disparity of the level of the basic pension,... Nowadays, the disparity of the basic pension in local regions of China can be described as follows: the low level of the unification of the basic pension systems, the large disparity of the level of the basic pension, and unfairness of the enterprises’ payment for the basic pension in different local regions in China. These have already brought many negative influences, which have greatly held back the development of the society and national economy. We should build the basic pension system in all local regions of China as a whole, which can cover all people and decrease the disparity in different local regions in China. 展开更多
关键词 the basic pension the disparity in the local regions harmonious development
下载PDF
An Image Segmentation Algorithm Based on a Local Region Conditional Random Field Model
8
作者 Xiao Jiang Haibin Yu Shuaishuai Lv 《International Journal of Communications, Network and System Sciences》 2020年第9期139-159,共21页
To reduce the computation cost of a combined probabilistic graphical model and a deep neural network in semantic segmentation, the local region condition random field (LRCRF) model is investigated which selectively ap... To reduce the computation cost of a combined probabilistic graphical model and a deep neural network in semantic segmentation, the local region condition random field (LRCRF) model is investigated which selectively applies the condition random field (CRF) to the most active region in the image. The full convolutional network structure is optimized with the ResNet-18 structure and dilated convolution to expand the receptive field. The tracking networks are also improved based on SiameseFC by considering the frame relations in consecutive-frame traffic scene maps. Moreover, the segmentation results of the greyscale input data sets are more stable and effective than using the RGB images for deep neural network feature extraction. The experimental results show that the proposed method takes advantage of the image features directly and achieves good real-time performance and high segmentation accuracy. 展开更多
关键词 Image Segmentation Local region Condition Random Field Model Deep Neural Network Consecutive Shooting Traffic Scene
下载PDF
Standization Trends in Local Regions Ningxia Hui Autonomous Region Utilizes Standardization to Promote Economic Development
9
《China Standardization》 2008年第1期26-27,共2页
In China, 10 ethnic minorities with a combined population of over 20 million people are followers of Islam. In Ningxia Hui Autonomous Region, the population is nearly 6 million, a-mong which the Islamic population is ... In China, 10 ethnic minorities with a combined population of over 20 million people are followers of Islam. In Ningxia Hui Autonomous Region, the population is nearly 6 million, a-mong which the Islamic population is about 2 million. In China as a whole, more than 20 million people enjoy eating food prepared according to Islamic guidelines, known as hal'al food. 展开更多
关键词 than more Standization Trends in Local regions Ningxia Hui Autonomous region Utilizes Standardization to Promote Economic Development over high
下载PDF
Regional Companies of PetroChina Expand Local Oil Products Market Rapidly
10
《China Oil & Gas》 CAS 2001年第4期46-47,共2页
关键词 regional Companies of PetroChina Expand Local Oil Products Market Rapidly
下载PDF
Source Mechanisms of Recent Earthquakes in Southern Saudi Arabia: Detecting of New Seismic Sources
11
作者 Ahmed Hosny Abdullah Mousa +2 位作者 Khaled Yousef Lotfy Samy Hamada Sadallah 《International Journal of Geosciences》 2023年第10期913-934,共22页
Recently in 2020, in southern Saudi Arabia three felt earthquakes occurred in Asir region, in the Khamis Mushait, Ahad Rafidah, and AL-Shuqiq area, of magnitude 3.45, 3.1, and 3.5, respectively. The most interesting e... Recently in 2020, in southern Saudi Arabia three felt earthquakes occurred in Asir region, in the Khamis Mushait, Ahad Rafidah, and AL-Shuqiq area, of magnitude 3.45, 3.1, and 3.5, respectively. The most interesting event was the earthquake that occurred in Khamis Mushait area, along a lake formed behind the Tadhah Dam (~7 km), fearing any damage to the dam’s body and the consequent destruction. Moment tensors for each event were computed for determining fault plane solutions, seismic moment, moment magnitude (Mw) and the CLVD ratio. In addition, the frequency contents in the waveforms of each event were identified. The obtained focal mechanisms represent different styles of faulting, normal movement with strike slip and strike slip with reverse. These tectonic movements on faults parallel to the Red Sea refer to the tensional forces due to the Red Sea rift system. These events occurred due to a natural tectonic movement, with considering the Khamis Mushait event as an induced event because of the lake behind the Dam. Many previous seismic hazard assessment studies have been conducted in southern Saudi Arabia without considering these recent seismic sources. Thus, our study provides new information related to detecting of new active seismic sources, which contributes to updating studies of seismic risk assessment in this region. In addition, our study pushes us to establish other additional seismic stations around these new seismic sources. This in turn will play a pivotal role in controlling seismic sources and then reassessing the seismic hazard in southern Saudi Arabia. 展开更多
关键词 New Seismic Sources Local and regional Stresses Updating Seismic Hazard
下载PDF
Engineering oxygen vacancies and localized amorphous regions in CuO-ZnO separately boost catalytic reactivity and selectivity
12
作者 Yongjun Ji Xiaoli Chen +9 位作者 Shaomian Liu Liwen Xing Xingyu Jiang Bin Zhang Huifang Li Wenxing Chen Ziyi Zhong Ligen Wang Guangwen Xu Fabing Su 《Nano Research》 SCIE EI CSCD 2023年第2期2126-2132,共7页
Generating different types of defects in heterogeneous catalysts for synergetic promotion of the reactivity and selectivity in catalytic reactions is highly challenging due to the lack of effective theoretical guidanc... Generating different types of defects in heterogeneous catalysts for synergetic promotion of the reactivity and selectivity in catalytic reactions is highly challenging due to the lack of effective theoretical guidance.Herein,we demonstrate a facile strategy to introduce two types of defects into the CuO-ZnO model catalyst,namely oxygen vacancies(OVs)induced by H2 partial reduction and localized amorphous regions(LARs)generated via the ball milling process.Using industrially important Rochow–Müller reaction as a representative,we found OVs predominantly improved the target product selectivity of dimethyldichlorosilane,while LARs significantly increased the conversion of reactant Si.The CuO-ZnO catalyst with optimized OVs and LARs contents achieved the best catalytic property.Theoretical calculation further revealed that LARs promote the generation of the Cu3Si active phase,and OVs impact the electronic structure of the Cu3Si active phase.This work provides a new understanding of the roles of different catalyst defects and a feasible way of engineering the catalyst structure for better catalytic performances. 展开更多
关键词 oxygen vacancy localized amorphous region CuO-ZnO catalyst REACTIVITY SELECTIVITY
原文传递
Developing chemical signatures of particulate air pollution in the Pearl River Delta region, China 被引量:3
13
作者 Mei Zheng Yuan Cheng +1 位作者 Limin Zeng Yuanhang Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第7期1143-1149,共7页
PM 2.5 samples were collected in a regional sampling network with three sites in Hong Kong and four sites in the adjacent inland Pearl River Delta (PRD) or Guangdong Province during four months/seasons from 2002–20... PM 2.5 samples were collected in a regional sampling network with three sites in Hong Kong and four sites in the adjacent inland Pearl River Delta (PRD) or Guangdong Province during four months/seasons from 2002–2003. Trans-boundary transport between Hong Kong and the inland PRD is inevitable under the influence of Asian monsoon. In summer, Hong Kong serves as the upwind site of the inland PRD while during other seasons it is under the influence of continental emissions. Previous studies have recognized the importance of using chemical signatures to differentiate local vs. regional contributions to air pollutants in Hong Kong such as the CO/NOx ratio, ratios of different VOC species. In this study, detailed chemical speciation by gas chromatography-mass spectrometry was performed with PM 2.5 samples to identify new chemical signatures to distinguish aerosols in Hong Kong from those from the inland PRD. Since Hong Kong is not influenced by the continental emissions from the inland PRD during summer, comparison focused on chemical data obtained from this season for chemical signatures. The new ratios developed from the current study include LCPI/HCPI ratio of alkanes (0.39 ± 0.02 in Hong Kong vs. 0.78 ± 0.08 in the inland PRD), pyrene to benzo[ghi]perylene ratio (0.97 ± 0.21 in Hong Kong compared to 0.20 ± 0.06 in the inland PRD), and the ratio of 1,2-benzenedioic acid to 1,4-benzenedioic acid (1.8 ± 0.1 in Hong Kong vs. 0.6 ± 0.05 in the inland PRD). Results from this study also revealed that Hong Kong was impacted by ship emissions as reflected by substantially high V/Ni ratio (9 ± 2) while this ratio was about 1–2 at all sites in the inland PRD, which is very close to typical ratios from residual oil combustion. 展开更多
关键词 PM 2.5 chemical signature local and regional air pollution Hong Kong Pearl River Delta
原文传递
Modulation of hot regions in waveguide-based evanescent-field-coupled localized surface plasmons for plasmon-enhanced spectroscopy 被引量:2
14
作者 HAILONG WANG YUYANG WANG +2 位作者 YI WANG WEIQING XU SHUPING XU 《Photonics Research》 SCIE EI 2017年第5期518-526,共9页
Coupling efficiency between the localized surface plasmons(LSPs) of metal nanoparticles(NPs) and incident light dominates the sensitivities of plasmon-based sensing spectroscopies and imaging techniques, e.g., surface... Coupling efficiency between the localized surface plasmons(LSPs) of metal nanoparticles(NPs) and incident light dominates the sensitivities of plasmon-based sensing spectroscopies and imaging techniques, e.g., surfaceenhanced Raman scattering(SERS) spectroscopy. Many endogenous features of metal NPs(e.g., size, shape,aggregation form, etc.) that have strong impacts on their LSPs have been discussed in detail in previous studies.Here, the polarization-tuned electromagnetic(EM) field that facilitates the LSP coupling is fully discussed.Numerical analyses on waveguide-based evanescent fields(WEFs) coupled with the LSPs of dispersed silver nanospheres and silver nano-hemispheres are presented and the applicability of the WEF-LSPs to plasmon-enhanced spectroscopy is discussed. Compared with LSPs under direct light excitation that only provide 3–4 times enhancement of the incidence field, the WEF-LSPs can amplify the electric field intensity about 30–90 times(equaling the enhancement factor of 10~6–10~8 in SERS intensity), which is comparable to the EM amplification of the SERS"hot spot" effect. Importantly, the strongest region of EM enhancement around silver nanospheres can be modulated from the gap region to the side surface simply by switching the incident polarization from TM to TE, which widely extends its sensing applications in surface analysis of monolayer of molecule and macromolecule detections. This technique provides us a unique way to achieve remarkable signal gains in many plasmon-enhanced spectroscopic systems in which LSPs are involved. 展开更多
关键词 NP Ag Modulation of hot regions in waveguide-based evanescent-field-coupled localized surface plasmons for plasmon-enhanced spectroscopy WEF
原文传递
Improving the process forming limit considering forming defects in the transitional region in local loading forming of Ti-alloy rib-web components 被引量:2
15
作者 Pengfei GAO Xiaodi LI +2 位作者 He YANG Xiaoguang FAN Zhenni LEI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2017年第3期1270-1280,共11页
The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by... The isothermal local loading forming technology provides a feasible way to form Ti-alloy large-scale rib-web components in aerospace and aviation fields.However,the local loading process forming limit is restricted by forming defects in the transitional region.In this work,the feasibility of controlling forming defects and improving the process forming limit by adjusting die parameters is explored through finite element(FE) simulation.It is found that the common cavum and folding defects in the transitional region are significantly influenced by the fillet radii of left rib and middle rib,respectively.The cavum and folding defects can be effectively controlled by increasing the fillet radii of left rib and middle rib,respectively.The process forming limits considering forming defects in the transitional region are determined by the stepwise searching method under various die parameters.Moreover,the relationship between the process forming limit and die parameters is developed through the response surface methodology(RSM).The developed RSM models suggest that increasing the fillet radii of left and middle ribs is effective to improve the process forming limit during local loading forming of rib-web components.The results will provide technical basis for the design of die parameters and the reduction amount,which is of great importance to control forming defects and improve the process forming limit in local loading forming of Ti-alloy large-scale rib-web components. 展开更多
关键词 Defect Large-scale rib-web component Local loading forming Process forming limit Transitional region
原文传递
Peroxyacetyl nitrate observed in Beijing in August from 2005 to 2009 被引量:4
16
作者 Tianyu Gao Li Han +4 位作者 Bin Wang Guang Yang Zhenqiang Xu Limin Zeng Jianbo Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第10期2007-2017,共11页
Measurements of peroxyacetyl nitrate(PAN) were made at a Beijing urban site each August from2005 to 2009. Over this 5-year period, the average PAN concentration for August in each year increased from 3(2005) to 11... Measurements of peroxyacetyl nitrate(PAN) were made at a Beijing urban site each August from2005 to 2009. Over this 5-year period, the average PAN concentration for August in each year increased from 3(2005) to 11.7 μg/m3(2007); however, it decreased rapidly in 2008(4.1 μg/m3).Generally, the variation over the 5 years showed a rise in the first part of the study period,followed by a decline. We considered two categories of local and regional air masses in this study, which revealed that the PAN concentration in Beijing was affected mainly by southeastern air masses. The August PAN variation was influenced predominantly by local air masses in 2005,but by 2009 regional air masses had become more important. This study showed the level and variation of PAN in the month of August in 5 consecutive years for the first time, and proved that control measures are useful in decreasing photochemical pollution; hence, these measures are probably feasible for other megacities too. Furthermore, this method of analyzing regional and local impacts might be useful for other studies as well. 展开更多
关键词 PAN Beijing Transport Local regional
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部