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The Cumulative Method for Multiplication and Division
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作者 Muna Mohammed Hammuda 《Applied Mathematics》 2024年第5期349-354,共6页
This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularl... This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularly multiplication and division. The operations of multiplication and division are represented by algebraic formulas. An advantage of the method is that the cumulative process can be performed on decimal numbers. The present paper aims to establish a basic and useful formula valid for the two fundamental arithmetic operations of multiplication and division. The new cumulative method proved to be more flexible and made it possible to extend the multiplication and division based on repeated addition/subtraction to decimal numbers. 展开更多
关键词 Multiplication and division Cumulative Method Repeated Process Decimal Numbers
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Machine learning solution for regional landslide susceptibility based on fault zone division strategy
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作者 WANG Yunhao WANG Luqi +5 位作者 LIU Songlin SUN Weixin LIU Pengfei ZHU Lin YANG Wenyu GUO Tong 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1745-1760,共16页
Landslide susceptibility assessment is an essential tool for disaster prevention and management. In areas with multiple fault zones, the impact of fault zone on slope stability cannot be disregarded. This study perfor... Landslide susceptibility assessment is an essential tool for disaster prevention and management. In areas with multiple fault zones, the impact of fault zone on slope stability cannot be disregarded. This study performed qualitative analysis of fault zones and proposed a zoning method to assess the landslide susceptibility in Chengkou County, Chongqing Municipality, China. The region within a distance of 1 km from the faults was designated as sub-zone A, while the remaining area was labeled as sub-zone B. To accomplish the assessment, a dataset comprising 388 historical landslides and 388 non-landslide points was used to train the random forest model. 10-fold cross-validation was utilized to select the training and testing datasets for the model. The results of the models were analyzed and discussed, with a focus on model performance and prediction uncertainty. By implementing the proposed division strategy based on fault zone, the accuracy, precision, recall, F-score, and AUC of both two sub-zones surpassed those of the whole region. In comparison to the results obtained for the whole region, sub-zone B exhibited an increase in AUC by 6.15%, while sub-zone A demonstrated a corresponding increase of 1.66%. Moreover, the results of 100 random realizations indicated that the division strategy has little effect on the prediction uncertainty. This study introduces a novel approach to enhance the prediction accuracy of the landslide susceptibility mapping model in areas with multiple fault zones. 展开更多
关键词 Landslide susceptibility mapping Fault division strategy Random forest GIS
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Does community-based health insurance affect lifestyle and timing of treatment seeking behavior?Evidence from Ethiopia
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作者 Zecharias Fetene Anteneh Anagaw D.Mebratie +2 位作者 Zemzem Shigute Getnet Alemu Arjun S.Bedi 《Global Health Journal》 2024年第2期83-90,共8页
Objectives This paper aims to investigate the effects of enrollment in the Ethiopian community-based health insurance(CBHI)scheme on household preventive care activities and the timing of treatment-seeking behavior fo... Objectives This paper aims to investigate the effects of enrollment in the Ethiopian community-based health insurance(CBHI)scheme on household preventive care activities and the timing of treatment-seeking behavior for illness symptoms.There is growing concern about the financial sustainability of CBHI schemes in developing countries.However,few empirical studies have identified potential contributors,including ex-ante and ex-post moral hazards.Methods We implement a household fixed-effect panel data regression model,drawing on three rounds of household survey data collected face to face in districts where CBHI scheme is operational and in districts where it is not operational in Ethiopia.Results The findings show that enrolment in CBHI does not significantly influence household behaviour regarding preventive care activities such as water treatment before drinking and handwashing before meals.However,CBHI significantly increases delay in treatment-seeking behaviour for diseases symptoms.Particularly,on average,we estimate about 4-6 h delay for malaria symptoms,a little above 4 h for tetanus,and 10-11 h for tuberculosis among the insured households.Conclusions While there is evidence that CBHI improve the utilization of outpatient or primary care services,our study suggests that insured members may wait longer before visiting health facilities.This delay could be partly due to moral hazard problems,as insured households,particularly those from rural areas,may consider the opportunity costs associated with visiting health facilities for minor symptoms.Overall,it is essential to identify the primary causes of delays in seeking medical services and implement appropriate interventions to encourage insured individuals to seek early medical attention. 展开更多
关键词 community-based health insurance Financial sustainability Preventive care Treatment-seeking behavior Household fixed effect Ethiopia
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Cell division cyclin 25C knockdown inhibits hepatocellular carcinoma development by inducing endoplasmic reticulum stress
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作者 Yan-Fei Li Fang-Yuan Zheng +4 位作者 Xin-Yu Miao Hai-Long Liu Yao-Yao Zhang Nai-Xia Chao Fa-Rong Mo 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2564-2574,共11页
BACKGROUND Cell division cyclin 25C(CDC25C)is a protein that plays a critical role in the cell cycle,specifically in the transition from the G2 phase to the M phase.Recent research has shown that CDC25C could be a pot... BACKGROUND Cell division cyclin 25C(CDC25C)is a protein that plays a critical role in the cell cycle,specifically in the transition from the G2 phase to the M phase.Recent research has shown that CDC25C could be a potential therapeutic target for cancers,particularly for hepatocellular carcinoma(HCC).However,the specific regulatory mechanisms underlying the role of CDC25C in HCC tumorigenesis and development remain incompletely understood.AIM To explore the impact of CDC25C on cell proliferation and apoptosis,as well as its regulatory mechanisms in HCC development.METHODS Hepa1-6 and B16 cells were transduced with a lentiviral vector containing shRNA interference sequences(LV-CDC25C shRNA)to knock down CDC25C.Subsequently,a xenograft mouse model was established by subcutaneously injecting transduced Hepa1-6 cells into C57BL/6 mice to assess the effects of CDC25C knockdown on HCC development in vivo.Cell proliferation and migration were evaluated using a Cell Counting Kit-8 cell proliferation assays and wound healing assays,respectively.The expression of endoplasmic reticulum(ER)stress-related molecules(glucose-regulated protein 78,X-box binding protein-1,and C/EBP homologous protein)was measured in both cells and subcutaneous xenografts using quantitative real-time PCR(qRT-PCR)and western blotting.Additionally,apoptosis was investigated using flow cytometry,qRT-PCR,and western blotting.RESULTS CDC25C was stably suppressed in Hepa1-6 and B16 cells through LV-CDC25C shRNA transduction.A xenograft model with CDC25C knockdown was successfully established and that downregulation of CDC25C expression significantly inhibited HCC growth in mice.CDC25C knockdown not only inhibited cell proliferation and migration but also significantly increased the ER stress response,ultimately promoting ER stress-induced apoptosis in HCC cells.CONCLUSION The regulatory mechanism of CDC25C in HCC development may involve the activation of ER stress and the ER stress-induced apoptosis signaling pathway. 展开更多
关键词 Cell division cyclin 25C Hepatocellular carcinoma Endoplasmic reticulum stress PROLIFERATION Apoptosis
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Rural labor migration and farmers’arrangements of rice production systems in Central China:Insight from the intergenerational division of labor
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作者 Xue Shen Quanyu Yang +1 位作者 Rongjun Ao Shengsheng Gong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3200-3214,共15页
Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a di... Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied extensively.Labor migration in rural China has taken new forms in recent years.There has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm work.The phenomenon has notably shaped the intergenerational division of labor(IDL)within households.However,it remains to be seen how farmers adjust their rice production systems in response to the IDL.The age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the IDL.Based on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service availability.Further analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational transfer.Monetary transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL households.This study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security. 展开更多
关键词 labor migration intergenerational division of labor rice production systems fuzzy regression discontinuity Central China
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Structural characteristics and tectonic division of the Zambezi Delta basin in the offshore East Africa:evidences from gravity and seismic data
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作者 Guozhang Fan Wen Li +8 位作者 Liangbo Ding Wanyin Wang Hongping Wang Dingding Wang Lin Li Hao Wang Chaofeng Wang Qingluan Wang Ying Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第4期105-118,共14页
The Zambezi Delta basin is a passive marginal basin located on the East African coast that has good oil and gas exploration potential.Due to the special geological evolutionary background of the Beira High in the Zamb... The Zambezi Delta basin is a passive marginal basin located on the East African coast that has good oil and gas exploration potential.Due to the special geological evolutionary background of the Beira High in the Zambezi Delta basin,it has a low gravity anomaly,and the existing seismic survey lines do not cover the whole basin;therefore,it is difficult to interpret the structural characteristics of the whole basin based solely on gravity or seismic data.Based on satellite altimetry gravity anomaly data,this study infers the distribution characteristics of faults in the Zambezi Delta basin by using the normalized vertical derivative of the total horizontal derivative(NVDR-THDR)technique.Then,constrained by seismic data,the gravity anomaly at the Moho interface is extracted by using the fast forward method of the double-interface model of the gravity anomaly,and this anomaly is then removed from the Bouguer gravity anomaly to obtain the sedimentary layer gravity anomaly.The thickness of the sedimentary strata is obtained by inversing the sedimentary basement depth of the whole basin.Then,uplifts and depressions are divided based on a sedimentary layer thickness of 3 km.This research demonstrates that the Zambezi Delta basin mainly features nearly SN-trending and NE-trending faults and that these faults exhibit east-west partitioning.The nearly SN-trending strike-slip faults controlled the sedimentary development of the basin,and the NE-trending tensile faults may have acted as migration channels for oil,gas and magma.The“overcompensation”effect of the Moho interface gravity anomaly on the gravity anomaly of the sedimentary layer is caused by the depression of the Moho interface beneath the Beira High,which results in a low gravity anomaly value for the Beira High.The pattern of uplifts and depressions trends NE and has the structural characteristics of east-west blocks. 展开更多
关键词 Zambezi Delta basin satellite altimetry gravity anomaly Beira High fault division uplift and depression pattern
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Adjustment of Administrative Divisions and Upgrading of Industrial Structure in Hefei Metropolitan Area:Taking"Partitions of Chaohu"as a Quasi-natural Experiment
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作者 Yumin DING 《Asian Agricultural Research》 2024年第7期19-23,27,共6页
Administrative regions are an important environment for the operation of China's market economy.The relevant economic subjects cannot predict the policy of adjustment of administrative divisions and carry out cons... Administrative regions are an important environment for the operation of China's market economy.The relevant economic subjects cannot predict the policy of adjustment of administrative divisions and carry out conscious migration behavior,adjustment of administrative divisions can be regarded as a quasi-natural experiment.The three cities of Hefei,Wuhu,and Ma'anshan,which are directly related to the adjustment of the administrative division of Chaohu,are taken as the treatment group,and the seven adjacent cities of Lu'an,Huainan,Chuzhou,Bengbu,Anqing,Chizhou,and Tongling are taken as the control group.Differences-in-Differences method and relevant control variables affecting the upgrading of industrial structure are used to test.The test results show that"Partitions of Chaohu"has a significant industrial structure upgrading effect by promoting the optimization of spatial layout,the cross-regional flow of production factors and the effective management of Chaohu Lake Basin.At the same time,the increase of total retail sales of consumer goods,urban fixed assets investment,public utility expenses in science,education,culture and health,and population plays a significant positive role in promoting the upgrading of industrial structure,while foreign direct investment plays a certain inhibition role in the upgrading of industrial structure.In order to meet the ever-developing space demands and enhance the impact on surrounding areas,the Hefei metropolitan area should be driven by technological innovation,strengthen the integration of industrial chains,improve the business environment and transportation network,and continuously promote the upgrading of industrial structure and the formation and development of new productive forces. 展开更多
关键词 Adjustment of administrative divisions Upgrading of industrial structure Hefei metropolitan area Quasi-natural experiment
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Community-Based Hepatitis B Campaign in Asian Americans
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作者 Chul S. Hyun Soonsik Kim +1 位作者 Sarah Hyun Joseph McMenamin 《International Journal of Clinical Medicine》 CAS 2024年第9期389-412,共24页
Chronic hepatitis B (CHB) disproportionately affects minority groups in the US, particularly Asian Americans, with numerous factors contributing to this disparity. Of the 2.4 million people living with chronic HBV in ... Chronic hepatitis B (CHB) disproportionately affects minority groups in the US, particularly Asian Americans, with numerous factors contributing to this disparity. Of the 2.4 million people living with chronic HBV in the US, 60% are Asian American. Many are unaware of their status and lack access to proper clinical care, with less than ten percent receiving necessary antiviral treatment. Barriers to screening and care include lack of disease awareness, language and cultural barriers, and financial constraints. Additionally, healthcare providers and systems in the US often overlook the importance of CHB, leading to inadequate care. In response, the Center for Viral Hepatitis (CVH) has implemented a community-based outreach program over the past sixteen years, employing a multifaceted approach involving all sectors of society and various organizations to combat health disparities in CHB. This grassroots campaign has proven highly effective, leveraging CVH’s leadership in spearheading numerous collaborative activities with community members, healthcare professionals, and policymakers. We have summarized the key points of CVH's efforts and their significance in combating CHB-related health disparities. The CHB Screening and Awareness Campaign, tailored to the Asian American community, serves as a successful model for increasing CHB screening, linkage-to-care, and addressing socio-cultural barriers and health literacy. Insights from these outreach programs have guided the development of culturally relevant resources and education initiatives. These findings suggest that such community-driven approaches are essential for addressing health disparities. The strategies and outcomes of CVH’s efforts can inform future health initiatives for other minority communities in the US and globally. 展开更多
关键词 Chronic Hepatitis B (CHB) Hepatitis B Virus (HBV) Health Disparity Health Inequity Asian Americans Cultural Competence in Healthcare community-based Screening Linkage-to-Care (LTC)
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Community-Based Approach in the Prevention and Management of Flood Disasters in Babessi Sub-Division (Ndop Plain, North West Cameroon) 被引量:2
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作者 Pamela Aka Tangan Primus Azinwi Tamfuh +4 位作者 Alice Magha Mufur Evine Laure Tanko Njiosseu Jules Nfor Aminatou Fagny Mefire Dieudonné Bitom 《Journal of Geoscience and Environment Protection》 2018年第4期211-228,共18页
Flood is a recurrent natural disaster that has caused enormous human and material damage in many places and continues to hit local committees at an alarming rate. The need to setup permanent committees to prevent and ... Flood is a recurrent natural disaster that has caused enormous human and material damage in many places and continues to hit local committees at an alarming rate. The need to setup permanent committees to prevent and manage flood disasters by local communities is therefore indispensable. In rural areas, the creation of such a structure is always a welcome relief to flood victims but it is often marred by numerous management problems. This study aimed to analyze the community-based approach in the prevention and management of flood disasters in Babessi Subdivision (North West Cameroon), to identify the causes of flood disasters and the preventive strategies used by this local community. A total number of 300 questionnaires as well as structured interviews were used to collect data in the field and the data were analyzed by simple descriptive statistics. The main results revealed that the main cause of flood disasters is heavy and consistent rainfall. Also, poor refuse disposal and drainage system management contribute to floods. The identification of areas likely to be affected by floods and preventing the riparian population from constructing houses along these areas especially beside the main rivers are the flood preventive measures adopted by the local flood management committee. The flood victims are reluctant to relocate to the settlement site earmarked by the Government, meanwhile, the local flood committee do not have the legal tools to forcefully relocate them. The population of Babessi needs to be sensitized on the impending dangers of flood hazard and be encouraged to participate in implementing the adopted strategies to prevent and manage subsequent flood disasters. 展开更多
关键词 DISASTER Management Flood community-based APPROACH Ndop PLAIN NORTH West Cameroon
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Time-sequential color code division multiplexing holographic display with metasurface 被引量:9
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作者 Xin Li Qinmiao Chen +4 位作者 Xue Zhang Ruizhe Zhao Shumin Xiao Yongtian Wang Lingling Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第8期8-16,共9页
Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface ho... Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface holography can only realize static manipulation.In this study,we propose and demonstrate a multiplexing metasurface technique combined with multiwavelength code-division multiplexing(CDM)to realize dynamic manipulation.Multicolor code references are utilized to record information within a single metasurface and increase the information capacity and security for anticracks.A total of 48 monochrome images consisting of pure color characters and multilevel color video frames were reconstructed in dual polarization channels of the birefringent metasurface to exhibit high information density,and a video was displayed via sequential illumination of the corresponding code patterns to verify the ability of dynamic manipulation.Our approach demonstrates significant application potential in optical data storage,optical encryption,multiwavelengthversatile diffractive optical elements,and stimulated emission depletion microscopy. 展开更多
关键词 metasurface color holography dynamic display code division multiplexing
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Performance of phase-matching quantum key distribution based on wavelength division multiplexing technology 被引量:1
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作者 马海强 韩雁鑫 +1 位作者 窦天琦 李鹏云 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期103-107,共5页
Quantum key distribution(QKD) generates information-theoretical secure keys between two parties based on the physical laws of quantum mechanics. The phase-matching(PM) QKD protocol allows the key rate to break the qua... Quantum key distribution(QKD) generates information-theoretical secure keys between two parties based on the physical laws of quantum mechanics. The phase-matching(PM) QKD protocol allows the key rate to break the quantum channel secret key capacity limit without quantum repeaters, and the security of the protocol is demonstrated by using equivalent entanglement. In this paper, the wavelength division multiplexing(WDM) technique is applied to the PM-QKD protocol considering the effect of crosstalk noise on the secret key rate. The performance of PM-QKD protocol based on WDM with the influence of adjacent classical channels and Raman scattering is analyzed by numerical simulations to maximize the total secret key rate of the QKD, providing a reference for future implementations of QKD based on WDM techniques. 展开更多
关键词 quantum key distribution wavelength division multiplexing secret key rate
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Impact of community-based rehabilitation on quality of life and self-esteem of persons with physical disabilities and their family members
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作者 Joseph Umunnah Babatunde Adegoke +2 位作者 Chigozie Uchenwoke Chinonso Igwesi-Chidobe Grace Alom 《Global Health Journal》 2023年第2期87-93,共7页
Objective:Community-based rehabilitation(CBR)is a strategy by which persons living with disability(PWDs)access comprehensive rehabilitation services with limited evidence regarding its impact on the quality of life(QO... Objective:Community-based rehabilitation(CBR)is a strategy by which persons living with disability(PWDs)access comprehensive rehabilitation services with limited evidence regarding its impact on the quality of life(QOL)and self-esteem(SE)of PWDs and their family members.This study compared the QOL and SE of Nigerian PWDs in communities with and without a CBR programme(CBR and non-CBR respectively),and the family quality of life(FQOL)of their family members.Methods:Cross-sectional study involving 2604 PWDs(1302 in CBR and 1302 in non-CBR);5208 family members of PWDs(2604 in CBR and 2604 non-CBR),recruited from four randomly selected geo-political zones in Nigeria,purposive/consecutive selection of eight CBR programmes,PWDs and their family members(CBR and non-CBR).Outcomes assessed using Rosenberg Self-Esteem Scale(RSES),World Health Organization Quality of Life Instrument-short form(WHOQOL-BREF)and Beach Centre Family Quality of Life Instrument(BCFQOL).Mann-Whitney U test and Spearman's rank order correlation were used to analyse data at P<0.05.Results:PWDs in CBR scored higher in all domains of WHOQOL-BREF(P<0.0001 in all cases)and RSES than non-CBR group(P<0.0001).The CBR families scored significantly higher than non-CBR families in all domains(P<0.05)except Emotional Well-Being of the BCFQOL.The CBR group scores on Psychological and Social Health domains of the WHOQOL-BREF showed significant positive correlation with CBR families'Family Interaction(P=0.06)and Parenting(P=0.07)domains and total FQOL(P=0.07).Conclusion:Community-based rehabilitation positively impacted on SE and QOL of PWDs and their family members. 展开更多
关键词 community-based rehabilitation Persons living with disability Quality of life SELF-ESTEEM
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Production evolution patterns and development stage division of waterflooding oilfields
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作者 JI Bingyu XU Ting +2 位作者 GAO Xingjun YU Hongmin LIU He 《Petroleum Exploration and Development》 SCIE 2023年第2期433-441,共9页
The continuous growth of recoverable reserves in a waterflooding oilfield has a significant impact on the patterns of production evolution. A new production evolution model is established by improving the Weng Cycle m... The continuous growth of recoverable reserves in a waterflooding oilfield has a significant impact on the patterns of production evolution. A new production evolution model is established by improving the Weng Cycle model. With the new model, the statistical correspondence between the production decline stage and the reserve-production imbalance is clarified,and the correlation of water cut with the recovery percent of recoverable reserves is discussed, providing quantitative basis of reservoir engineering for dividing development stages of oilfield and defining mature oilfields. According to the statistics of oilfields in eastern China, the time point corresponding to the reserve-production balance coefficient dropping to less than 1dramatically is well correlated the beginning point of production decline, thus the time when the reserve-production balance coefficient drops dramatically can be taken as the initiation point of production decline stage. The research results show that the water cut and the recovery percent of recoverable reserves have a good statistical match in the high water cut stage, and it is more rational to take both the start point of production decline stage and the water cut of 90%(or the recovery percent of recoverable reserves of 80%) as the critical criteria for defining a mature oilfield. Five production evolution patterns can be summarized as follows: growth–peak plateau–stepped decline, growth–stepped stabilizing–stepped decline, growth–stepped stabilizing–rapid decline, growth–peak plateau–rapid decline, and growth–continuous decline. 展开更多
关键词 waterflooding oilfield production evolution development stage division recoverable reserves mature oilfield
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Improved PBFT Consensus Algorithm Based on Node Role Division
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作者 Xiyu Ren Xiangrong Tong Wei Zhang 《Journal of Computer and Communications》 2023年第2期20-38,共19页
The PBFT (Practical Byzantine Fault Tolerance, PBFT) consensus algorithm, which addressed the issue of malicious nodes sending error messages to disrupt the system operation in distributed systems, was challenging to ... The PBFT (Practical Byzantine Fault Tolerance, PBFT) consensus algorithm, which addressed the issue of malicious nodes sending error messages to disrupt the system operation in distributed systems, was challenging to support massive network nodes, the common participation over all nodes in the consensus mechanism would lead to increased communication complexity, and the arbitrary selection of master nodes would also lead to inefficient consensus. This paper offered a PBFT consensus method (Role Division-based Practical Byzantine Fault Tolerance, RD-PBFT) to address the above problems based on node role division. First, the nodes in the system voted with each other to divide the high reputation group and low reputation group, and determined the starting reputation value of the nodes. Then, the mobile node in the group was divided into roles according to the high reputation value, and a total of three roles were divided into consensus node, backup node, and supervisory node to reduce the number of nodes involved in the consensus process and reduced the complexity of communication. In addition, an adaptive method was used to select the master nodes in the consensus process, and an integer value was introduced to ensure the unpredictability and equality of the master node selection. Experimentally, it was verified that the algorithm has lower communication complexity and better decentralization characteristics compared with the PBFT consensus algorithm, which improved the efficiency of consensus. 展开更多
关键词 Blockchain Consensus Algorithm Practical Byzantine Fault Tolerance Node Role division
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The Epigenetic“Dance”of Cell Divisions
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作者 YAN Fusheng 《Bulletin of the Chinese Academy of Sciences》 2023年第3期164-165,共2页
The tango of life begins with the very first cell division.New research reveals that to dance their way through development,dividing cells must pass along not just DNA but molecular“memories”that guide their destini... The tango of life begins with the very first cell division.New research reveals that to dance their way through development,dividing cells must pass along not just DNA but molecular“memories”that guide their destinies.When this handoff gets fumbled,the dance falls apart. 展开更多
关键词 dividing DANCE division.
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Construction of Industrialization Development Model for"1+4+X"Community-Based Elderly Care in Gannan Old Revolutionary Base Area in the Context of Population Aging
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作者 Chenxin YANG Jun XIAO +2 位作者 Liyuan WANG Jiaxin LIU Yangkai LU 《Asian Agricultural Research》 2023年第5期8-10,16,共4页
In the context of controlling population development in a planned way,China entered an aging society in the early 21 st century.In this context,how to meet the needs of the elderly care and form an effective elderly c... In the context of controlling population development in a planned way,China entered an aging society in the early 21 st century.In this context,how to meet the needs of the elderly care and form an effective elderly care model has become a key problem to be solved urgently by local government departments.With the continuous advancement of the elderly care policy,the community-based elderly care has gradually become the mainstream and is in the stage of vigorous promotion.Taking the Gannan old revolutionary base area in Jiangxi Province as an example,this study puts forward"1+4+X"community-based elderly care model based on the policy system of community-based elderly care,the physical and mental health of the elderly,the material space and the construction of evaluation system,and explores how to promote the application of this community model efficiently in the form of industrialization,so as to drive the economic growth of the Gannan old revolutionary base area,promote the employment development and improve the community-based elderly care service. 展开更多
关键词 community-based elderly care New elderly care model Gannan old revolutionary base area
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Soil Organic Carbon and Nitrogen Dynamics in Arabica Coffee Agroforestry Systems in the Noun Division, West Cameroon
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作者 Abdel Malik Atoupka Emile Temgoua +2 位作者 Lucie Félicité Temgoua Jean Baurel Atchombou Steve Tassiamba 《Open Journal of Forestry》 2023年第3期262-277,共16页
Agroforestry systems (AFSs) offer viable solutions to climate change because of the below-ground biomass (BGB) that is maintained by the soil. Therefore, spatially explicit estimation of their BGB is crucial to accoun... Agroforestry systems (AFSs) offer viable solutions to climate change because of the below-ground biomass (BGB) that is maintained by the soil. Therefore, spatially explicit estimation of their BGB is crucial to account for emission reduction efforts. A study to assess soil organic carbon (SOC) and nitrogen dynamics in Arabica coffee agroforests was conducted in two subdivisions (Foumbot and Kouoptamo) of the Noun Division in western Cameroon. The methodological approach involved the collection of 150 soil samples taken at different depths: 0 - 10, 10 - 20 and 20 - 30 cm. Depending on the depth, the SOC stock is 27.93 ± 1.13 tC/ha at 10 cm depth, 22.37 ± 1.47 tC/ha at 20 cm and 20.79 ± 0.31 tC/ha at 30 cm. According to the age classes of the Arabica coffee systems (ACA), the C/N ratio in our study area averaged 26.94 ± 13.60 for the (5 - 20) year old systems in Foumbot and 60.64 ± 48.80 for the (20 - 35) year old systems in Kouoptamo. Depending on the depth, at 10 cm this ratio is higher in Kouoptamo than in Foumbot with a maximum value of 57 and 38 respectively for the two subdivisions. In view of the results obtained, it would be important to analyse the types of microorganisms responsible for the decomposition of organic matter which is linked to soil organic carbon. 展开更多
关键词 Agroforestry Systems Coffee Trees Soil Organic Carbon Noun division West Cameroon
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A High Spectral Efficient Frequency-Domain Channel-Estimation Method for the Polarization-Division-Multiplexed CO-OFDM-OQAM System
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作者 Hangyu Zhao Shuo Zhang +2 位作者 Daobin Wang Xiaoxiao Li Lihua Yuan 《Optics and Photonics Journal》 2023年第6期119-132,共14页
Contrary to the other multi-carrier modulation systems, the coherent optical orthogonal frequency division multiplexing communication system with an offset quadrature amplitude modulation (CO-OFDM-OQAM) possesses inhe... Contrary to the other multi-carrier modulation systems, the coherent optical orthogonal frequency division multiplexing communication system with an offset quadrature amplitude modulation (CO-OFDM-OQAM) possesses inherent imaginary interference (IMI). This has an important impact on the channel estimation process. Currently, a variety of frequency-domain channel estimation methods have been proposed. However, there are various problems that still exist. For instance, in order to reduce the influence of IMI, it is necessary to insert more guard intervals between the training sequence and the payload, leading to the occupation of excessive spectrum resources. In order to address this problem, this work designs a high spectral efficient frequency-domain channel estimation method for the polarization-division-multiplexing CO-OFDM-OQAM systems. First, the working principle of the proposed method is described in detail. Then, its spectral efficiency, power peak-to-average ratio, and channel estimation performance are studied based on simulations. The simulation results show that the proposed method improves the spectral efficiency without worsening the power peak-to-average ratio. The channel estimation capability of this method is verified in three scenarios of long-distance transmissions, including back-to-back, 100 km, and 200 km transmissions. . 展开更多
关键词 Orthogonal Frequency division Multiplexing (OFDM-OQAM) Polarization-division-Multiplexing (PDM) Channel Estimation Optical Communication System
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Modeling Daily Average Temperatures in a Coastal Site of Central Africa: An Analysis of Seasonal Divisions
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作者 Jean-Pierre Bell Esther C. Modi-Mbog +1 位作者 Nicodeme Djiedeu Laurent Nana 《Atmospheric and Climate Sciences》 2023年第3期341-352,共12页
The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This pap... The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This paper implements a simple analytical approach in order to generate daily average temperatures which implicitly accounts for surface heating and drivers through a comprehensive representation of station-based temperature records on a universal standard calendar propagated by the earth’s dynamics features. The modeled and observed pattern of daily temperatures exhibits a close agreement with the level of strength agreement exceeding 0.56. The extreme high and low values of the observed temperature patterns are equally well captured although model underestimates the probability of temperatures around the two modal peaks (~25.6℃ and 27.5℃). Additionally, a theoretical thermal-based division led to the identification of six seasons, including two hot and cold periods along with two pairs of mixed hot-cold. The theoretical division proposed here appears to be a good approximation for the understanding of rainfall seasonality in this area. 展开更多
关键词 Daily Temperature Estimates Earth’s Dynamics Seasonal divisions
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Residual Film Pollution in the Eighth Division of the Xinjiang Production and Construction Corps
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作者 Weijun LI Xingyao ZHANG +3 位作者 Nate KA Xianglin YANG Jianjiang LU Xuyun ZHANG 《Research and Application of Materials Science》 2023年第1期11-16,共6页
This study investigated the residual film content and distribution at different soil depths in the Eighth Division of the Xinjiang Production and Construction Corps.Before spring plowing in 2019,representative fields ... This study investigated the residual film content and distribution at different soil depths in the Eighth Division of the Xinjiang Production and Construction Corps.Before spring plowing in 2019,representative fields in four areas(Anjihai,Shihezi suburbs,Mosuowan and Xiayedi)were selected for residual film collection.The average content of residual film in the Eighth Division was 104 kg/ha.The residual film content in the four areas decreased in the order Anjihai>Shihezi suburbs>Mosuowan>Xiayedi.The average amount of residual film collected from cotton fields was greater than that from corn fields.Residual film content in the cotton field at soil depths of 0~10 and 10~30 cm was higher than that in the corn field,whereas the residual film content at a 30–50 cm soil depth in the corn field was higher than that in the cotton field.The results showed that farmers do not consider the long-term benefits,the high cost and short time of recycling,and the easy recycling of surface residual film.The shallow that the higher content of residual film,the less water in the soil of cotton.The same time,the results showed that the quantity of residual film in cotton field had greater influence on cotton quality. 展开更多
关键词 Eighth division Residual film POLLUTION Present situation PROBLEMS
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