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A Two-Stage Method for an Approximate Calculation of Statically Indeterminate Trusses 被引量:2
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作者 Janusz Rebielak 《Journal of Civil Engineering and Architecture》 2014年第5期567-572,共6页
The paper presents the principles of a method, which in two simple stages makes possible to carry out the statically calculation of values of forces acting in the fiat static indeterminate trusses. In each stage, it i... The paper presents the principles of a method, which in two simple stages makes possible to carry out the statically calculation of values of forces acting in the fiat static indeterminate trusses. In each stage, it is considered the static determinate truss, scheme of which is obtained after remove the suitable number of members from the basic static indeterminate truss. The both intermediate statically determinate trusses are of the same clear span and they are loaded by forces of half values applied to the corresponding truss nodes. The method applies one of the typical procedures of calculation of the statically determinate trusses and then it is applied in an appropriate way the rule of superposition for obtaining the final values of forces acting in particular members of the basic truss. The values of forces calculated in this way are of a very close approximation to the force values determined in the special and complex ways being considered as the exact calculation methods. The proposed method can be useful mostly but not only for the initial structural design of such systems. The simplicity of the two-stage method justifies an assumption that it can be relatively easy and worthy to adjust to the requirements of the computer aided technology of statically calculation of the complex forms of trusses. 展开更多
关键词 Method of static calculation truss structure static indeterminate truss static determinate truss rule of superposition.
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Homeostatic Determinate Systems and Thermodynamics of Selforganization and Evolution of Material World 被引量:1
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作者 Lev E. Panin 《Journal of Modern Physics》 2011年第5期354-369,共16页
The paper considers new approaches to system analysis of natural phenomena in physics, chemistry and bi- ology. It lays the foundation of the homeostatic determinate systems theory that allows revealing the mecha- nis... The paper considers new approaches to system analysis of natural phenomena in physics, chemistry and bi- ology. It lays the foundation of the homeostatic determinate systems theory that allows revealing the mecha- nism by which the basic principle of natural science, determinism, is being realized. Evolution of the mate- rial world is represented as inevitable and continuous growth of orderliness (negentropy) based on transition from one type of determinate systems to another. Increasing negentropy is shown to be closely associated with continuous accumulation of information, which determines the natural diversity in physics, chemistry and biology. 展开更多
关键词 Homeostatic determinate System THERMODYNAMICS EVOLUTION
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Statically Determinate Equations of Equilibrium in Particulate Mechanics
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作者 Wu Bingkun Center of Rock and Soil Mechanics, Southwest Jiaotong University, Chengdu 610031, China 《Journal of Modern Transportation》 1996年第1期2-15,共14页
Based on a model of two stress tensors possessing high fluidity, a statically determinate system of partial difference equations of equilibrium has been derived for use to particulate media... Based on a model of two stress tensors possessing high fluidity, a statically determinate system of partial difference equations of equilibrium has been derived for use to particulate media of such nature. Through non dimensionalization of independent and dependent variables, the system passes into that of partial differential equations. Although the statically determinate system of partial differential equations is non linear, yet the two dimensional one falls apart into three separate groups which can be solved easily one after another. 展开更多
关键词 particulate mechanics statically determinate system stress tensor
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Influence of the Interaction of the Mutant Inl Gene and the Type of Fruiting Branches ss on the Anatomical Features of the Stem in the Indeterminate and Determinant Forms of <i>G. hirsutum</i>L.
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作者 Akmal A.Yuldashev Guljan M.Duschanova +1 位作者 Miradkham F.Abzalov Gayrat N.Jurakulov 《American Journal of Plant Sciences》 2020年第4期538-548,共11页
For the first time, a comparative analysis of the structure of the apical meristem and the node of the main shoot of two forms of the indeterminate kind Namangan-77 and the determinant line of Determinant-2 and Determ... For the first time, a comparative analysis of the structure of the apical meristem and the node of the main shoot of two forms of the indeterminate kind Namangan-77 and the determinant line of Determinant-2 and Determinant-3 of G. hirsutum in the kidney ding phase was carried out. In the apical meristem of the indeterminate form Namangan-77 is characterized by the recessive homozygous state of the mutant gene (inlinl) and the dominant homozygous, heterozygous state of the fruiting branch gene S-s: inlinlSS, inlinlSs, inlinlss—more pronounced vegetative, vegetative, with this, this form is predominated by the continuation of first-order shoots and the monopodial branching type with unlimited apical growth, accompanied by a uniform elongation of the internodes. In the apical meristem, in the forms of the determinant lines, Determinant-2 and Determinant-3 are characterized by the dominant homozygous state of the mutant gene (InlInl) and the recessive homozygous state of the allelic gene (ss)—InlInlss—there is a generative collateral kidney in the axillary leaf axial sinus, which is why these forms of the vegetative apex of the shoot when they transit to the reproductive state turn into a floral apical meristem and a sympodial branching type what happens through the development of inflorescences. Obviously, this is a consequence of a change in the phytohormonal status in the apical part of the stem as a result of the interaction of the mutant gene Inl and gene S. The node of the main stem in all forms was also studied, and a three-beam-three-lacuna type of structure was revealed, which is a fairly persistent characterizing feature of large taxa and can be used in their taxonomy. 展开更多
关键词 MUTANT GENE Allele Anatomy STEM INdeterminate DETERMINANT Monopodial Sympodial
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Determinates of Childhood Pneumonia and Diarrhea with Special Emphasis to Exclusive Breastfeeding in North Achefer District, Northwest Ethiopia: A Case Control Study
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作者 Molla Gedefaw Resom Berhe 《Open Journal of Epidemiology》 2015年第2期107-112,共6页
Studies showed that exclusive breast feeding reduced infant morbidity and mortality. In low income countries such as Ethiopia where under-five mortality is very high, the role of exclusively breastfeeding could be eve... Studies showed that exclusive breast feeding reduced infant morbidity and mortality. In low income countries such as Ethiopia where under-five mortality is very high, the role of exclusively breastfeeding could be even more critical. However, studies assessing the place of exclusive breast freeing in the prevention of childhood illnesses in our area are scarce. The aim of the study was to identify determinant factors of childhood pneumonia and diarrhoea. An institution based case control study was conducted in Achefer District in July, 2012. The cases were 122 children of 7 - 24 months old who had repeated attack of diarrhoea or pneumonia over three months prior to the survey while controls were 122 children who visited well baby clinic for vaccination. Data were collected by using pre-tested and structured questionnaire, and analysed using SPSS version 16 for windows. Logistic regression was performed, and strength of associations was estimated using odds ratio and 95% confidence interval. About 83% of the controls and only 12.3% of the cases were exclusively breast fed. Children who were exclusively breast fed were 83 times less likely to develop pneumonia or diarrhea than those who were not exclusively fed. Marital status, monthly income, prelacteal feeding, and late initiation of breast feeding were found to have statistically significant association with childhood diarrhea and pneumonia. This study brought local evidence that exclusive breast feeding had a protective effect against common childhood infectious diseases—pneumonia and diarrhoea—in the study area. Therefore, culture sensitive and plausible health education is recommended to strengthen exclusive breast feeding practices in order to decrease mortality and morbidity of infants and children from pneumonia and diarrhoea. 展开更多
关键词 EXCLUSIVE Breast Feeding DETERMINANT Factors CHILDHOOD Pneumonia DIARRHEA Ethiopia
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An Improved Test Method and Numerical Analysis for Crack Opening Resistance of FRC Round Determinate Panels 被引量:2
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作者 GU Qian XU Hanfeng MINDESS Sidney 《Wuhan University Journal of Natural Sciences》 CAS 2009年第1期47-52,共6页
This paper presents a numerical analysis of a material test program investigating the crack opening properties of fibre reinforced concrete (FRC) round determinate panels (RDP). The objective of this research is t... This paper presents a numerical analysis of a material test program investigating the crack opening properties of fibre reinforced concrete (FRC) round determinate panels (RDP). The objective of this research is to set up a modified RDP test method to improve the current ASTM C1550 test method for FRC and fibre reinforced shotcrete (FRS) composite. By this test method, light small-diameter panels are applied and more crack information can be obtained by a new rotation angle measuring technique. It is shown that this modified test method can be used to effectively evaluate the crack opening resistance of FRC. The finite element analysis was then performed to clarify the crack propaga- tions and failure mode of FRC RDP panels. It helps establish a reasonable theoretical method to predict the structural response of RDP. combining with this modified testing technioue. 展开更多
关键词 fibre reinforced concrete test method round determinate panel finite element analysis crack opening
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LoRa Sense:Sensing and Optimization of LoRa Link Behavior Using Path-Loss Models in Open-Cast Mines
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作者 Bhanu Pratap Reddy Bhavanam Prashanth Ragam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期425-466,共42页
The Internet of Things(IoT)has orchestrated various domains in numerous applications,contributing significantly to the growth of the smart world,even in regions with low literacy rates,boosting socio-economic developm... The Internet of Things(IoT)has orchestrated various domains in numerous applications,contributing significantly to the growth of the smart world,even in regions with low literacy rates,boosting socio-economic development.This study provides valuable insights into optimizing wireless communication,paving the way for a more connected and productive future in the mining industry.The IoT revolution is advancing across industries,but harsh geometric environments,including open-pit mines,pose unique challenges for reliable communication.The advent of IoT in the mining industry has significantly improved communication for critical operations through the use of Radio Frequency(RF)protocols such as Bluetooth,Wi-Fi,GSM/GPRS,Narrow Band(NB)-IoT,SigFox,ZigBee,and Long Range Wireless Area Network(LoRaWAN).This study addresses the optimization of network implementations by comparing two leading free-spreading IoT-based RF protocols such as ZigBee and LoRaWAN.Intensive field tests are conducted in various opencast mines to investigate coverage potential and signal attenuation.ZigBee is tested in the Tadicherla open-cast coal mine in India.Similarly,LoRaWAN field tests are conducted at one of the associated cement companies(ACC)in the limestone mine in Bargarh,India,covering both Indoor-toOutdoor(I2O)and Outdoor-to-Outdoor(O2O)environments.A robust framework of path-loss models,referred to as Free space,Egli,Okumura-Hata,Cost231-Hata and Ericsson models,combined with key performance metrics,is employed to evaluate the patterns of signal attenuation.Extensive field testing and careful data analysis revealed that the Egli model is the most consistent path-loss model for the ZigBee protocol in an I2O environment,with a coefficient of determination(R^(2))of 0.907,balanced error metrics such as Normalized Root Mean Square Error(NRMSE)of 0.030,Mean Square Error(MSE)of 4.950,Mean Absolute Percentage Error(MAPE)of 0.249 and Scatter Index(SI)of 2.723.In the O2O scenario,the Ericsson model showed superior performance,with the highest R^(2)value of 0.959,supported by strong correlation metrics:NRMSE of 0.026,MSE of 8.685,MAPE of 0.685,Mean Absolute Deviation(MAD)of 20.839 and SI of 2.194.For the LoRaWAN protocol,the Cost-231 model achieved the highest R^(2)value of 0.921 in the I2O scenario,complemented by the lowest metrics:NRMSE of 0.018,MSE of 1.324,MAPE of 0.217,MAD of 9.218 and SI of 1.238.In the O2O environment,the Okumura-Hata model achieved the highest R^(2)value of 0.978,indicating a strong fit with metrics NRMSE of 0.047,MSE of 27.807,MAPE of 27.494,MAD of 37.287 and SI of 3.927.This advancement in reliable communication networks promises to transform the opencast landscape into networked signal attenuation.These results support decision-making for mining needs and ensure reliable communications even in the face of formidable obstacles. 展开更多
关键词 Internet of things long range wireless area network ZigBee mining environments path-loss models coefficient of determination mean square error
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Prevalence and Determinants of Erectile Dysfunction in Adult Diabetic Patients in the Southwest Region of Cameroon
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作者 Divine Enoru Eyongeta Cyril Kamadjou +3 位作者 Boris Amougou Oteh Njockawoh Mpey Glennis T. Ayuk Fru F. Angwafo III 《Journal of Biosciences and Medicines》 2025年第2期413-426,共14页
Background: Erectile dysfunction (ED) is a common, bothersome and relatively under diagnosed complication of diabetes mellitus. This study was aimed to determine the prevalence of erectile dysfunction and its determin... Background: Erectile dysfunction (ED) is a common, bothersome and relatively under diagnosed complication of diabetes mellitus. This study was aimed to determine the prevalence of erectile dysfunction and its determinants. Methods: A cross-sectional hospital-based study was carried out in the Diabetology Units of the Buea and Limbe Regional Hospitals involving 332 male patients with diabetes and aged over 21 years. Data was analyzed using Stata and R version 3.5.3. Results: The mean age of the participants was 55years. Most participants (64.46%) were married. About half (50.60%) of the participants actively consumed alcohol, 11.45% were smokers and 57.83% were sedentary. 18 participants (5.42%) recorded high risk sexual behaviour. 54.32% of participants had a comorbidity and 43.90% were overweight. The prevalence of diabetic ED was 78.92%. Age, Fasting Blood Sugar and Glycated hemoglobin were found to be positive determinants of diabetic ED (odds ratio (OR) = 0.77, 95% CI −0.1 - 0.07). Conclusion: The prevalence of diabetic ED in this hospital population study is high, and both physician and patient—initiated measures are needed to reduce this prevalence and improve awareness, recognition and care of this condition. 展开更多
关键词 Erectile Dysfunction Diabetes Mellitus PREVALENCE Determinants
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Determinants of generalized anxiety and construction of a predictive model in patients with chronic obstructive pulmonary disease
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作者 Yi-Pu Zhao Wei-Hua Liu Qun-Cheng Zhang 《World Journal of Psychiatry》 2025年第2期48-58,共11页
BACKGROUND Patients with chronic obstructive pulmonary disease(COPD)frequently experience exacerbations requiring multiple hospitalizations over prolonged disease courses,which predispose them to generalized anxiety d... BACKGROUND Patients with chronic obstructive pulmonary disease(COPD)frequently experience exacerbations requiring multiple hospitalizations over prolonged disease courses,which predispose them to generalized anxiety disorder(GAD).This comorbidity exacerbates breathing difficulties,activity limitations,and social isolation.While previous studies predominantly employed the GAD 7-item scale for screening,this approach is somewhat subjective.The current literature on predictive models for GAD risk in patients with COPD is limited.AIM To construct and validate a GAD risk prediction model to aid healthcare professionals in preventing the onset of GAD.METHODS This retrospective analysis encompassed patients with COPD treated at our institution from July 2021 to February 2024.The patients were categorized into a modeling(MO)group and a validation(VA)group in a 7:3 ratio on the basis of the occurrence of GAD.Univariate and multivariate logistic regression analyses were utilized to construct the risk prediction model,which was visualized using forest plots.The model’s performance was evaluated using Hosmer-Lemeshow(H-L)goodness-of-fit test and receiver operating characteristic(ROC)curve analysis.RESULTS A total of 271 subjects were included,with 190 in the MO group and 81 in the VA group.GAD was identified in 67 patients with COPD,resulting in a prevalence rate of 24.72%(67/271),with 49 cases(18.08%)in the MO group and 18 cases(22.22%)in the VA group.Significant differences were observed between patients with and without GAD in terms of educational level,average household income,smoking history,smoking index,number of exacerbations in the past year,cardiovascular comorbidities,disease knowledge,and personality traits(P<0.05).Multivariate logistic regression analysis revealed that lower education levels,household income<3000 China yuan,smoking history,smoking index≥400 cigarettes/year,≥two exacerbations in the past year,cardiovascular comorbidities,complete lack of disease information,and introverted personality were significant risk factors for GAD in the MO group(P<0.05).ROC analysis indicated that the area under the curve for predicting GAD in the MO and VA groups was 0.978 and 0.960.The H-L test yieldedχ^(2) values of 6.511 and 5.179,with P=0.275 and 0.274.Calibration curves demonstrated good agreement between predicted and actual GAD occurrence risks.CONCLUSION The developed predictive model includes eight independent risk factors:Educational level,household income,smoking history,smoking index,number of exacerbations in the past year,presence of cardiovascular comorbidities,level of disease knowledge,and personality traits.This model effectively predicts the onset of GAD in patients with COPD,enabling early identification of high-risk individuals and providing a basis for early preventive interventions by nursing staff. 展开更多
关键词 Chronic obstructive pulmonary disease Generalized anxiety disorder Predictive model Determinants analysis Forest plot
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Impact of Social Determinants on Vector-Borne Parasitic Diseases in Chad: A Case Study of Grand-Sido and Kouh-Est
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作者 Mahamat Alhadj Moussa Ibrahim Abdelsalam Hassan Gogo +5 位作者 Hassane Mahamat Hassane Petra Berger Djoukzoumka Signaboubo Aly Savadogo Abdelsalam Tidjani Soerge Kelm 《Open Journal of Applied Sciences》 2025年第1期110-126,共17页
Background: Social determinants of health (SDOH) significantly influence diseases with environmental components, like vector-borne parasitic diseases. This study aims to examine how these factors influence vector-born... Background: Social determinants of health (SDOH) significantly influence diseases with environmental components, like vector-borne parasitic diseases. This study aims to examine how these factors influence vector-borne parasitic diseases (VBPDs) transmission in Chad and provide recommendations for policy improvements. Methods: The study adopts the WHO Conceptual Framework of SDOH to compare two regions in Southern Chad: Kouh-Est, which has an ongoing vector control program, and Grand-Sido, which lacks such a program. The study includes both nomadic and sedentary populations to provide a comprehensive understanding of the SDOH influencing VBPDs. Households were randomly selected. Data on sociodemographic characteristics, literacy, knowledge of VBPDs and protective measures, and access to education and health facilities were collected. Results: A total of 202 households from 17 villages, including 820 participants, were surveyed. Agriculture, livestock, and fishing were the main occupations, involving 84.1% of participants. Literacy was low, with 36.7% non-educated, 47.7% completing primary school, 14.5% secondary school, and only 0.3% reaching tertiary education. Most villages lacked schools beyond the primary level, and nomadic populations were significantly less educated than sedentary ones (p Conclusion: Educational deficiencies, lack of protective measures against vectors, inadequate healthcare resources, and lifestyle conditions aggravated by poor road infrastructure, limited transportation, and economic constraints contribute to worsened VBPDs outcomes in these rural populations. Addressing these systemic issues in the surveyed communities is essential for improving health equity and VBPDs outcomes in these regions specifically and in similar populations settings more broadly. 展开更多
关键词 Social Determinants of Health Vector-Borne Parasitic Diseases CHAD
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Asymptotic Behaviors of Hankel Determinants Whose Entries Involve Regularly- or Rapidly-Varying Functions. Part II*
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作者 Antonio Granata 《Advances in Pure Mathematics》 2025年第2期119-144,共26页
Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the la... Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the last results in the paper highlight analogies between algebraic identities for Hankelians with special entries and asymptotic relations valid for large classes of entries. 展开更多
关键词 Asymptotic Behaviors of Hankel Determinants Asymptotic Expansions in the Real Domain Regularly- Rapidly- and Exponentially-Varying Functions of Higher Order Algebraic Identities for Hankelians
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Effects of water and nitrogen rate on grain-filling characteristics under high-low seedbed cultivation in winter wheat
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作者 Junming Liu Zhuanyun Si +6 位作者 Shuang Li Lifeng Wu Yingying Zhang Xiaolei Wu Hui Cao Yang Gao Aiwang Duan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第12期4018-4031,共14页
A high-efficiency mode of high-low seedbed cultivation(HLSC)has been listed as the main agricultural technology to increase land utilization ratio and grain yield in Shandong Province,China.However,limited information... A high-efficiency mode of high-low seedbed cultivation(HLSC)has been listed as the main agricultural technology to increase land utilization ratio and grain yield in Shandong Province,China.However,limited information is available on the optimized water and nitrogen management for yield formation,especially the grain-filling process,under HLSC mode.A three-year field experiment with four nitrogen rates and three irrigation rates of HLSC was conducted to reveal the response of grain-filling parameters,grain weight percentage of spike weight(GPS),spike moisture content(SMC),and winter wheat yield to water and nitrogen rates.The four nitrogen rates were N1(360 kg ha^(-1) pure N),N2(300 kg ha^(-1) pure N),N3(240 kg ha^(-1) pure N),and N4(180 kg ha^(-1) pure N),respectively,and the three irrigation quotas were W1(120 mm),W2(90 mm),and W3(60 mm),respectively.Results showed that the determinate growth function generally performed well in simulating the temporal dynamics of grain weight(0.989<R^(2)<0.999,where R2 is the determination coefficient).The occurrence time of maximum filling rate(T_(max))and active grain-filling period(AGP)increased with the increase in the water or nitrogen rate,whereas the average grain-filling rate(G_(mean))had a decreasing trend.The final 1,000-grain weight(FTGW)increased and then decreased with the increase in the nitrogen rates and increased with the increase in the irrigation rates.The GPS and SMC had a highly significant quadratic polynomial relationship with grain weight and days after anthesis.Nitrogen,irrigation,and year significantly affected the T_(max),AGP,G_(mean),and FTGW.Particularly,the AGP and FTGW were insignificantly different between high seedbed(HLSC-H)and low seedbed(HLSC-L)across the water and nitrogen levels.Moreover,the moderate water and nitrogen supply was more beneficial for grain yield,as well as for spike number and grain number per hectare.The principal component analysis indicated that combining 240-300 kg N ha^(-1) and 90^(-1)20 mm irrigation quota could improve grain-filling efficiency and yield for the HLSC-cultivated winter wheat. 展开更多
关键词 high-low seedbed cultivation water and nitrogen grain filling determinate growth equation wheat yield
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Two-Stage Planning of Distributed Power Supply and Energy Storage Capacity Considering Hierarchical Partition Control of Distribution Network with Source-Load-Storage 被引量:1
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作者 Junhui Li Yuqing Zhang +4 位作者 Can Chen Xiaoxiao Wang Yinchi Shao Xingxu Zhu Cuiping Li 《Energy Engineering》 EI 2024年第9期2389-2408,共20页
Aiming at the consumption problems caused by the high proportion of renewable energy being connected to the distribution network,it also aims to improve the power supply reliability of the power system and reduce the ... Aiming at the consumption problems caused by the high proportion of renewable energy being connected to the distribution network,it also aims to improve the power supply reliability of the power system and reduce the operating costs of the power system.This paper proposes a two-stage planning method for distributed generation and energy storage systems that considers the hierarchical partitioning of source-storage-load.Firstly,an electrical distance structural index that comprehensively considers active power output and reactive power output is proposed to divide the distributed generation voltage regulation domain and determine the access location and number of distributed power sources.Secondly,a two-stage planning is carried out based on the zoning results.In the phase 1 distribution network-zoning optimization layer,the network loss is minimized so that the node voltage in the area does not exceed the limit,and the distributed generation configuration results are initially determined;in phase 2,the partition-node optimization layer is planned with the goal of economic optimization,and the distance-based improved ant lion algorithm is used to solve the problem to obtain the optimal distributed generation and energy storage systemconfiguration.Finally,the IEEE33 node systemwas used for simulation.The results showed that the voltage quality was significantly improved after optimization,and the overall revenue increased by about 20.6%,verifying the effectiveness of the two-stage planning. 展开更多
关键词 Zoning control two-stage planning site selection and capacity determination optimized scheduling improved ant lion algorithm
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Optimization of Extraction Process for Total Flavonoids from Penthorum chinense Pursh and Comparison of Their Contents from Different Parts 被引量:1
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作者 Hongsheng LIU Jiqiang YAO +2 位作者 Xue BAI Jianying KANG Yefei YUAN 《Medicinal Plant》 2024年第2期10-14,共5页
[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experimen... [Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh. 展开更多
关键词 Penthorum chinense Pursh Total flavonoids Orthogonal experiments Extraction process Content determination
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DETERMINE评分与急性心肌梗死PCI术预后关系的分析
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作者 李加乐 刘泽岩 程景林 《中文科技期刊数据库(引文版)医药卫生》 2024年第5期0051-0054,共4页
探讨DETERMINE评分(病理性Q波导联数*2+碎裂QRS波导联数+T波倒置导联数)与急性心肌梗死患者经皮冠状动脉介入(PCI)术后预后的关系。方法 选择2021.1-2022.12在我院住院接受PCI治疗的急性心肌梗死患者206例,根据预后情况分为预后良好组(... 探讨DETERMINE评分(病理性Q波导联数*2+碎裂QRS波导联数+T波倒置导联数)与急性心肌梗死患者经皮冠状动脉介入(PCI)术后预后的关系。方法 选择2021.1-2022.12在我院住院接受PCI治疗的急性心肌梗死患者206例,根据预后情况分为预后良好组(165例)和预后不良组(41例)。比较两组患者的临床资料及DETERMINE评分,采用多因素Logistic回归法分析影响急性心肌梗死PCI术后预后的相关因素;创建受试者工作特征曲线(ROC),分析DETERMINE评分对急性心肌梗死PCI术后预后的预测价值。分析急性心肌梗死PCI术预后不良的影响因素。结果 与预后良好组比较,预后不良组糖尿病史、心律失常史比例及DETERMINE评分、年龄、体重指数、左室射血分数、糖化血红蛋白、低密度脂蛋白胆固醇、总胆固醇水平均显著升高,差异具有统计学意义;二元Logistic回归分析显示DETERMINE评分、心律失常史、体重指数、糖化血红蛋白、低密度脂蛋白胆固醇是冠心病患者PCI手术预后不良的独立危险因素(OR=1.443~15.658,P<0.05)。结论 DETERMINE评分与冠心病PCI术预后相关,需引起临床关注。 展开更多
关键词 DETERMINE评分 急性心肌梗死 PCI术后 预后
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A Coordinate-Free Approach to the Design of Generalized Griffis-Duffy Platforms
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作者 Chengwei Shen Xu Pei +1 位作者 Lubin Hang Jingjun Yu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期95-103,共9页
Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes uncontrollable.PMs remaining permanently in a singularity are beneficial... Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes uncontrollable.PMs remaining permanently in a singularity are beneficial for linearto-rotary motion conversion.Griffis-Duffy(GD)platform is a mobile structure admitting a Bricard motion.In this paper,we present a coordinate-free approach to the design of generalized GD platforms,which consists in determining the shape and attachment of both the moving platform and the fixed base.The generalized GD platform is treated as a combination of six coaxial single-loop mechanisms under the same constraints.Owing to the inversion,hidden in the geometric structure of these single-loop mechanisms,the mapping from a line to a circle establishes the geometric transformation between the fixed base and the moving platform based on the center of inversion,and describes the shape and attachment of the generalized GD platform.Moreover,the center of inversion not only identifies the location of rotation axis,but also affects the shape of the platform mechanism.A graphical construction of generalized GD platforms using inversion,proposed in the paper,provides geometrically feasible solutions of the manipulator design for the requirement of the location of rotation axis. 展开更多
关键词 Generalized Griffis-Duffy platforms SELF-MOTION INVERSION Coordinate-free determination Manipulator design
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Silencing transformer and transformer-2 in Zeugodacus cucurbitae causes defective sex determination with inviability of most pseudomales
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作者 Qin Ma Zizhen Fan +5 位作者 Ping Wang Siya Ma Jian Wen Fengqin Cao Xianwu Lin Rihui Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期938-947,共10页
transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbi... transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked Maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control. 展开更多
关键词 Zeugodacus cucurbitae TRANSFORMER transformer-2 sex determination RNA interference biological control
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Review of the Low-Lying Excited Baryons ∑^(*)(1/2^(-))
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作者 En Wang Li-Sheng Geng +2 位作者 Jia-Jun Wu Ju-Jun Xie Bing-Song Zou 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第10期31-37,共7页
Strong empirical and phenomenological indications exist for large sea-quark admixtures in the low-lying excited baryons.Investigating the low-lying excited baryon ∑^(*)(1/2^(-))is important for determining the nature... Strong empirical and phenomenological indications exist for large sea-quark admixtures in the low-lying excited baryons.Investigating the low-lying excited baryon ∑^(*)(1/2^(-))is important for determining the nature of the low-lying excited baryons.We review the experimental and theoretical progress on the studies of the ∑^(*)(1/2^(-)). 展开更多
关键词 EXCITED QUARK DETERMINING
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Ionization Potential Depression Model for Warm/Hot and Dense Plasmas
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作者 Chensheng Wu Fuyang Zhou +4 位作者 Jun Yan Xiang Gao Yong Wu Chunhua Zeng Jianguo Wang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期45-57,共13页
For warm/hot and dense plasmas(WDPs),ionization potential depression(IPD)plays a crucial role in determining its ionization balance and understanding the resultant microscopic plasma properties.A sophisticated and uni... For warm/hot and dense plasmas(WDPs),ionization potential depression(IPD)plays a crucial role in determining its ionization balance and understanding the resultant microscopic plasma properties.A sophisticated and unified IPD model is necessary to resolve those existing discrepancies between theoretical and experimental results.However,the applicability of those widely used IPD models nowadays is limited,especially for the nonlocal thermodynamic equilibrium(non-LTE)dense plasma produced by short-pulse laser.In this work,we propose an IPD model that considers inelastic atomic processes,in which three-body recombination and collision ionization processes are found to play a crucial role in determining the electron distribution and IPD for a WDP.This IPD model is validated by reproducing latest experimental results of Al plasmas with a wide-range condition of 70 eV–700 eV temperature and 0.2–3 times solid density,as well as a typical non-LTE system of hollow Al ions.It is demonstrated that the present IPD model has a significant temperature dependence due to the consideration of the inelastic collision processes.With a lower computational cost and wider application range of plasma conditions,the proposed model is expected to provide a promising tool to study the ionization balance and the atomic processes,as well as the related radiation and particle transports properties of the WDP. 展开更多
关键词 properties. COLLISION DETERMINING
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foxl2l is a germ cell-intrinsic gatekeeper of oogenesis in zebrafish
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作者 Zhiqin Ren Ding Ye +5 位作者 Naike Su Chaofan Wang Lijia He Houpeng Wang Mudan He Yonghua Sun 《Zoological Research》 SCIE CSCD 2024年第5期1116-1130,共15页
Zebrafish serve as a valuable model organism for studying germ cell biology and reproductive processes.The AB strain of zebrafish is proposed to exhibit a polygenic sex determination system,where most males initially ... Zebrafish serve as a valuable model organism for studying germ cell biology and reproductive processes.The AB strain of zebrafish is proposed to exhibit a polygenic sex determination system,where most males initially develop juvenile ovaries before committing to male fate.In species with chromosomal sex determination,gonadal somatic cells are recognized as key determinants of germ cell fate.Notably,the loss of germ cells in zebrafish leads to masculinization,implying that germ cells harbor an intrinsic feminization signal.However,the specific signal triggering oogenesis in zebrafish remains unclear.In the present study,we identified foxl2l as an oocyte progenitor-specific gene essential for initiating oogenesis in germ cells.Results showed that foxl2l-knockout zebrafish bypassed the juvenile ovary stage and exclusively developed into fertile males.Further analysis revealed that loss of foxl2l hindered the initiation of oocyte-specific meiosis and prevented entry into oogenesis,leading to premature spermatogenesis during early gonadal development.Furthermore,while mutation of the pro-male gene dmrt1 led to fertile female differentiation,simultaneous disruption of foxl2l in dmrt1 mutants completely blocked oogenesis,with a large proportion of germ cells arrested as germline stem cells,highlighting the crucial role of foxl2l in oogenesis.Overall,this study highlights the unique function of foxl2l as a germ cell-intrinsic gatekeeper of oogenesis in zebrafish. 展开更多
关键词 foxl2l DMRT1 OOGENESIS Sex determination MEIOSIS
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