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Low-Carbon Dispatch of an Integrated Energy System Considering Confidence Intervals for Renewable Energy Generation
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作者 Yan Shi Wenjie Li +2 位作者 Gongbo Fan Luxi Zhang Fengjiu Yang 《Energy Engineering》 EI 2024年第2期461-482,共22页
Addressing the insufficiency in down-regulation leeway within integrated energy systems stemming from the erratic and volatile nature of wind and solar renewable energy generation,this study focuses on formulating a c... Addressing the insufficiency in down-regulation leeway within integrated energy systems stemming from the erratic and volatile nature of wind and solar renewable energy generation,this study focuses on formulating a coordinated strategy involving the carbon capture unit of the integrated energy system and the resources on the load storage side.A scheduling model is devised that takes into account the confidence interval associated with renewable energy generation,with the overarching goal of optimizing the system for low-carbon operation.To begin with,an in-depth analysis is conducted on the temporal energy-shifting attributes and the low-carbon modulation mechanisms exhibited by the source-side carbon capture power plant within the context of integrated and adaptable operational paradigms.Drawing from this analysis,a model is devised to represent the adjustable resources on the charge-storage side,predicated on the principles of electro-thermal coupling within the energy system.Subsequently,the dissimilarities in the confidence intervals of renewable energy generation are considered,leading to the proposition of a flexible upper threshold for the confidence interval.Building on this,a low-carbon dispatch model is established for the integrated energy system,factoring in the margin allowed by the adjustable resources.In the final phase,a simulation is performed on a regional electric heating integrated energy system.This simulation seeks to assess the impact of source-load-storage coordination on the system’s low-carbon operation across various scenarios of reduction margin reserves.The findings underscore that the proactive scheduling model incorporating confidence interval considerations for reduction margin reserves effectively mitigates the uncertainties tied to renewable energy generation.Through harmonized orchestration of source,load,and storage elements,it expands the utilization scope for renewable energy,safeguards the economic efficiency of system operations under low-carbon emission conditions,and empirically validates the soundness and efficacy of the proposed approach. 展开更多
关键词 Integrated energy system carbon capture power plant confidence interval optimized scheduling
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Serum Vitamin E Reference Intervals in a Black Congolese Population of Kinshasa
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作者 Monzango Sibo Mboloko Esimo +16 位作者 Mputu Lobota Mbemba Fundu Nganga Mireille Itewa Monka Mayoka Mamoi Ntanga Kabuya Amba Naomie Lezaka Ensemeya Bola Jonita Maxime Fastrez Lebwaze Bienvenu Balthazar Phoba Destin Mbongi Tshilolo Léon Kahindo P. Muyalalo Mbanzulu Pita Emile Darai 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第4期737-744,共8页
Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aime... Context: Vitamin E is a powerful antioxidant and plays an important role in human reproduction. However, micronutrient deficiency is a major public health problem, particularly in developing countries. This study aimed to establish reference intervals (RIs) for vitamin E in black Congolese people of childbearing age using an ELISA method to provide a reference for clinically assessing vitamin E status. Methods: A total of 127 healthy people between the ages of 20 and 42 who underwent check-ups were randomly selected for the study. ELISA method measured the level of vitamin E. The effect of gender on vitamin E level was assessed, and RI was established using a parametric approach. Results: Women showed significantly higher levels of vitamin E than men (p = 0.01). The RI of vitamin E in people of childbearing age was 3.71 to 13.72, 4.52 to 14.64, and 4.17 to 13.52 mg/L, respectively, for the whole population, women and men. Conclusion: Using an ELISA method, this study established RI for vitamin E in the black Congolese population of childbearing age. We also found that women had significantly higher vitamin E levels than men. The results could provide a scientific basis for interpreting vitamin status in people of childbearing age in our setting. 展开更多
关键词 ELISA Reference interval People of Childbearing Age Vitamin E
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Effect of the interval between two shocks on ejecta formation from the grooved aluminum surface
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作者 Mingyang Xu Jianli Shao +1 位作者 Weidong Song Enling Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期147-159,共13页
This work focuses on the effect of the interval between two shocks on the ejecta formation from the grooved aluminum(Al_(1100))surface by using smoothed particle hydrodynamics numerical simulation.Two unsupported shoc... This work focuses on the effect of the interval between two shocks on the ejecta formation from the grooved aluminum(Al_(1100))surface by using smoothed particle hydrodynamics numerical simulation.Two unsupported shocks are obtained by the plate-impact between sample and two flyers at interval,with a peak pressure of approximately 30 GPa for each shock.When the shock interval varies from 2.11 to 7.67 times the groove depth,the bubble velocity reduces to a constant,and the micro jetting factor R_(J) from spike to bubble exhibits a non-monotonic change that decreases initially and then increases.At a shock interval of 3.6 times the groove depth,micro jetting factor R_(J) from spike to bubble reaches its minimum value of approximately 0.6.While,the micro jetting factor R_(F) from spike to free surface decreases linearly at first,and stabilizes around 0.25 once the shock interval surpasses 4.18 times the groove depth.When the shock interval is less than 4.18 times the groove depth,the unloading wave generated by the breakout of the first shock wave is superimpose with the unloading part of the second shock wave to form a large tensile area. 展开更多
关键词 EJECTA MICROJET Two shocks intervAL Smoothed particle hydrodynamics
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Optimizing profile line interval for enhanced accuracy in rock joint morphology and shear strength assessments
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作者 Leibo Song Quan Jiang +5 位作者 Shigui Du Jiamin Song Gang Wang Yanting Gu Xingkai Wang Jinzhong Wu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第5期587-608,共22页
2D profile lines play a critical role in cost-effectively evaluating rock joint properties and shear strength.However,the interval(DIL)between these lines significantly impacts roughness and shear strength assessments... 2D profile lines play a critical role in cost-effectively evaluating rock joint properties and shear strength.However,the interval(DIL)between these lines significantly impacts roughness and shear strength assessments.A detailed study of 45 joint samples using four statistical measures across 500 different DIL values identified a clear line interval effect with two stages:stable and fluctuation-discrete.Further statistical analysis showed a linear relationship between the error bounds of four parameters,shear strength evaluation,and their corresponding maximum DIL values,where the gradient k of this linear relationship was influenced by the basic friction angle and normal stress.Accounting for these factors,lower-limit linear models were employed to determine the optimal DIL values that met error tolerances(1%–10%)for all metrics and shear strength.The study also explored the consistent size effect on joints regardless of DIL changes,revealing three types of size effects based on morphological heterogeneity.Notably,larger joints required generally higher DIL to maintain the predefined error limits,suggesting an increased interval for large joint analyses.Consequently,this research provides a basis for determining the optimal DIL,improving accuracy in 2D profile line assessments of joint characteristics. 展开更多
关键词 Rock joint ROUGHNESS Shear strength Size effect Profile line interval effect
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An improved interval model updating method via adaptive Kriging models
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作者 Sha WEI Yifeng CHEN +1 位作者 Hu DING Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期497-514,共18页
Interval model updating(IMU)methods have been widely used in uncertain model updating due to their low requirements for sample data.However,the surrogate model in IMU methods mostly adopts the one-time construction me... Interval model updating(IMU)methods have been widely used in uncertain model updating due to their low requirements for sample data.However,the surrogate model in IMU methods mostly adopts the one-time construction method.This makes the accuracy of the surrogate model highly dependent on the experience of users and affects the accuracy of IMU methods.Therefore,an improved IMU method via the adaptive Kriging models is proposed.This method transforms the objective function of the IMU problem into two deterministic global optimization problems about the upper bound and the interval diameter through universal grey numbers.These optimization problems are addressed through the adaptive Kriging models and the particle swarm optimization(PSO)method to quantify the uncertain parameters,and the IMU is accomplished.During the construction of these adaptive Kriging models,the sample space is gridded according to sensitivity information.Local sampling is then performed in key subspaces based on the maximum mean square error(MMSE)criterion.The interval division coefficient and random sampling coefficient are adaptively adjusted without human interference until the model meets accuracy requirements.The effectiveness of the proposed method is demonstrated by a numerical example of a three-degree-of-freedom mass-spring system and an experimental example of a butted cylindrical shell.The results show that the updated results of the interval model are in good agreement with the experimental results. 展开更多
关键词 interval model updating(IMU) non-probabilistic uncertainty adaptive Kriging model surrogate model grey number
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Upper and Lower Bounds of the α-Universal Triple I Method for Unified Interval Implications
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作者 Yiming Tang Jianwei Gao Yifan Huang 《Computers, Materials & Continua》 SCIE EI 2024年第4期1063-1088,共26页
Theα-universal triple I(α-UTI)method is a recognized scheme in the field of fuzzy reasoning,whichwas proposed by our research group previously.The robustness of fuzzy reasoning determines the quality of reasoning al... Theα-universal triple I(α-UTI)method is a recognized scheme in the field of fuzzy reasoning,whichwas proposed by our research group previously.The robustness of fuzzy reasoning determines the quality of reasoning algorithms to a large extent,which is quantified by calculating the disparity between the output of fuzzy reasoning with interference and the output without interference.Therefore,in this study,the interval robustness(embodied as the interval stability)of theα-UTI method is explored in the interval-valued fuzzy environment.To begin with,the stability of theα-UTI method is explored for the case of an individual rule,and the upper and lower bounds of its results are estimated,using four kinds of unified interval implications(including the R-interval implication,the S-interval implication,the QL-interval implication and the interval t-norm implication).Through analysis,it is found that theα-UTI method exhibits good interval stability for an individual rule.Moreover,the stability of theα-UTI method is revealed in the case of multiple rules,and the upper and lower bounds of its outcomes are estimated.The results show that theα-UTI method is stable for multiple rules when four kinds of unified interval implications are used,respectively.Lastly,theα-UTI reasoning chain method is presented,which contains a chain structure with multiple layers.The corresponding solutions and their interval perturbations are investigated.It is found that theα-UTI reasoning chain method is stable in the case of chain reasoning.Two application examples in affective computing are given to verify the stability of theα-UTImethod.In summary,through theoretical proof and example verification,it is found that theα-UTImethod has good interval robustness with four kinds of unified interval implications aiming at the situations of an individual rule,multi-rule and reasoning chain. 展开更多
关键词 Fuzzy reasoning the CRI method the triple I method fuzzy implication interval robustness
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The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study
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作者 Jieying Wu Shan Ye +2 位作者 Xiangyi Liu Yingsheng Xu Dongsheng Fan 《Neural Regeneration Research》 SCIE CAS 2025年第5期1505-1512,共8页
Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives ... Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis. 展开更多
关键词 amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread
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Left ventricular hypertrophy amplifies the QT,and Tp-e intervals and the Tp-e/QT ratio of left chest ECG 被引量:6
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作者 Zhao Zhao Zuyi Yuan Yuqiang Ji Yue Wu Yinzhi Qi 《The Journal of Biomedical Research》 CAS 2010年第1期69-72,共4页
Objective: To evaluate the changes in Tp-e interval (an interval from the peak to the end of the T wave), QT interval and Tp-e/QT ratio of the body surface ECG in patients with left ventricular hypertrophy (LVH).... Objective: To evaluate the changes in Tp-e interval (an interval from the peak to the end of the T wave), QT interval and Tp-e/QT ratio of the body surface ECG in patients with left ventricular hypertrophy (LVH). Methods: The Tp-e interval and QT interval were measured on body surface ECGs in 42 patients without either hypertension or LVH (control group), 41 patients having hypertension but not LVH (non-LVH group), and 38 patients with both hypertension and LVH (LVH group). Results: The mean corrected QT (QTc) interval, and mean corrected Tp-e[T(p-e)c] interval were significantly longer in the LVH group (0.430±0.021s vs. 0.409±0.019s, p 〈 0.01; 0.098±0.013s vs. 0.088±0.011s, respectively) than those in the control group. The Tp-e/QT ratio was also amplified in LVH group (0.232± 0.028 vs.0.218± 0.027) (p 〈 0.05). Conclusion: LVH increased the QT interval, Tp-e interval and Tp-e/QT ratio of the body surface ECG. 展开更多
关键词 HYPERTENSION left ventricular hypertrophy QT interval Tp-e interval ARRHYTHMIA
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Average recurrence intervals of strong earthquakes and potential risky segments along the Taiyuan-Linfen portion of the Shanxi graben system 被引量:6
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作者 易桂喜 闻学泽 徐锡伟 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第4期426-437,共12页
Since the great 1303 Hongtong, Shanxi, earthquake of magnitude 8, 700 years have elapsed. To analyze the long-term seismic potential, this paper divides the Taiyuan-Linfen portion of the Shanxi graben system into 5 se... Since the great 1303 Hongtong, Shanxi, earthquake of magnitude 8, 700 years have elapsed. To analyze the long-term seismic potential, this paper divides the Taiyuan-Linfen portion of the Shanxi graben system into 5 seismogenic segments. Based on data of historical earthquakes and GPS observation, the authors estimate mean seismic-moment rates and average recurrence intervals of strong earthquakes for the individual segments, and fur-ther analyze relative levels of current stress cumulation on the segments based on mapping b-values along the gra-ben system by using the network seismic data for the recent over 30 years. The main result shows that the Linfen basin segment has an estimated mean seismic-moment rate of 2.211016 Nm/a to 3.031016 Nm/a, and its average recurrence interval for M=7.5 earthquake is estimated to be between 1 560 and 2 140 years. For the Ling-shi-Hongtong segment, the estimated average recurrence interval for M=8 earthquakes is between 4 300 and 5 100 years, equivalent to having a mean moment-rate of 2.581016 Nm/a to 3.101016 Nm/a. The contour map of b-values shows that the two segments of Lingshi-Hongtong and Linfen basin have been being at low or relatively low stress levels, reflecting that since the 1303 M=8 and the 1695 M=7.5 earthquake ruptures, the fault-planes strengths of the both segments have not been resumed yet. And the other two segments, the Houma and the Jiexiu-Fenyang, have relatively high stress levels, and have been already identified as potential risky segments for the coming earthquakes from the analysis combining with the estimated average recurrence intervals of earth-quakes on the both segments. 展开更多
关键词 historical earthquakes seismogenic segment moment rate average recurrence interval poten-
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Assessment of Impacts of Public Health Interventions on the SARS Epidemic in Beijing in Terms of the Intervals Between Its Symptom Onset, Hospital Admission, and Notification 被引量:3
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作者 WAN-NIANLIANG MINLIU +3 位作者 ZE-JUNLIU XIONGHE YUEPAN XUE-QINXIE 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第3期153-158,共6页
关键词 SARS intervals interventions IMPACTS
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Analysis of petrophysical cutoffs of reservoir intervals with production capacity and with accumulation capacity in clastic reservoirs 被引量:4
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作者 Wang Yanzhong Cao Yingchang +3 位作者 Song Guoqi Song Ling Yang Tian Zhang Shaomin 《Petroleum Science》 SCIE CAS CSCD 2014年第2期211-219,共9页
Methodologies have been developed for calculating cutoffs of reservoir intervals with production capacity (RIPC) and reservoir intervals with accumulation capacity (RIAC) according to the types of pore throat stru... Methodologies have been developed for calculating cutoffs of reservoir intervals with production capacity (RIPC) and reservoir intervals with accumulation capacity (RIAC) according to the types of pore throat structures and dynamic force by using data from petrophysical analysis, production tests and mercury injection. The data are from clastic reservoirs in the third member (Es3) and the fourth member (Es4) of the Shahejie Formation in the Shengtuo area on the North Slope of the Dongying Sag, Jiyang Depression, China. The method of calculating cutoffs of RIPC is summarized as follows: 1) determination of permeability cutoffs of RIPC; 2) classification of types of pore-throat structures according to mercury injection data and then relating porosity to permeability and determining the relationship between porosity and permeability according to each type of pore-throat structure; and 3) calculating porosity cutoffs of RIPC using established correlation between porosity and permeability according to the type of pore throat structure. The method of calculating cutoffs of RIAC includes: 1) establishing a functional relationship between oil-water interracial tension and formation temperature; 2) calculating limiting values of maximum connected pore-throat radii according to formation temperature and dynamic forces of each reservoir interval; 3) correlating permeability with maximum connected pore-throat radius and then obtaining permeability cutoffs of RIAC; and 4) calculating porosity cutoffs on the basis of permeability cutoffs according to specific correlations, suitable for the type of porethroat structure. The results of this study show that porosity and permeability cutoffs of clastic reservoirs decrease with depth. For a fixed permeability cutoff, the porosity cutoff of R1PC varies because the type of pore throat is different. At a fixed temperature, porosity and permeability cutoffs of RIAC decrease as dynamic force increases. For a fixed permeability cutoff of effective hydrocarbon accumulation, the porosity cutoff also varies with different types of pore throat. 展开更多
关键词 Effective reservoir petrophysical cutoff of reservoir intervals with production capacity(RIPC) petrophysical cutoff of reservoir intervals with accumulation capacity (RIAC) clastic rocks
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Multiple-target tracking with adaptive sampling intervals for phased-array radar 被引量:10
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作者 Zhenkai Zhang Jianjiang Zhou +2 位作者 Fei Wang Weiqiang Liu Hongbing Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第5期760-766,共7页
A novel adaptive sampling interval algorithm for multitarget tracking is presented. This algorithm which is based on interacting multiple models incorporates the grey relational grade (GRG) into the particle swarm o... A novel adaptive sampling interval algorithm for multitarget tracking is presented. This algorithm which is based on interacting multiple models incorporates the grey relational grade (GRG) into the particle swarm optimization (PSO). Firstly, the desired tracking accuracy is set for each target. Secondly, sampling intervals are selected as particles, and then the advantage of the GRG is taken as the measurement function for resource management. Meanwhile, the fitness value of the PSO is used to measure the difference between desired tracking accuracy and estimated tracking accuracy. Finally, it is suggested that the radar should track the target whose prediction value of the next sampling interval is the smallest. Simulations show that the proposed method improves both the tracking accuracy and tracking efficiency of the phased-array radar. 展开更多
关键词 target tracking adaptive sampling interval (ASI) particle swarm optimization (PSO) grey relational grade (GRG) phased-array radar.
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Determination of reference intervals for metabolic profile of Hanwoo cows at early, middle and late gestation periods 被引量:1
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作者 Da Chuan Piao Tao Wang +4 位作者 Jae Sung Lee Renato SA Vega Sang Ki Kang Yun Jaie Choi Hong Gu Lee 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2015年第2期252-256,共5页
Background: Metabolic profile was initially designed as a presymptomatic diagnostic aid based on statistical analyses of blood metabolites to provide an early warning of certain types of metabolic disorder. However, ... Background: Metabolic profile was initially designed as a presymptomatic diagnostic aid based on statistical analyses of blood metabolites to provide an early warning of certain types of metabolic disorder. However, there is little metabolic profile data available about Korean Hanwoo cows. Therefore, this study aimed to determine the reference intervals of metabolic profile for Korean Hanwoo cows. Methods: Healthy animals (2,205) were selected and divided into early (day 1 to 95), middle (day 96 to 190) and late (day 191 to 285) period according to their gestating period. Metabolic profile including total protein (TP), albumin (AIb), urea (UREA), glucose (Glu), total cholesterol (T-Cho), long-chain fatty acid (LCFA), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), creatinine (Crea), calcium (Ca), inorganic phosphorous (iP) and magnesium (Mg) were analyzed using a TBA-4OFR automatic biochemical analyzer. The data of Korean Hanwoo cows were then compared to those of the Japanese Wagyu cows. Results: Most of the data of the Korean Hanwoo cows were relatively higher than those of Japanese Wagyu cows, with the exception of Glu and GGT. This may indicate that the nutritional level of feed for the Korean Hanwoo cows was higher than that of the Japanese Wagyu cows because of the different feeding system. In particular, relatively higher levels of UREA and LCFA were observed in the Korean Hanwoo cows, and this may also contribute to the low reproduction efficiency. Conclusions: These findings may provide some theoretical basis for understanding the reproductive and feeding situation of Korean Hanwoo cows. 展开更多
关键词 Hanwoo cows Metabolic profile Reference intervals Wagyu cows
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Effect of Saline Water Application through Different Irrigation Intervals on Tomato Yield and Soil Properties 被引量:2
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作者 Mahmoud Rahil Hajaj Hajjeh Alia Qanadillo 《Open Journal of Soil Science》 2013年第3期143-147,共5页
A field study was conducted on the experimental farm of ministry of agriculture, located at Palestine Technical University-Kadoorie, to investigate the effects of saline water irrigation through three irrigation inter... A field study was conducted on the experimental farm of ministry of agriculture, located at Palestine Technical University-Kadoorie, to investigate the effects of saline water irrigation through three irrigation intervals on yield of tomato crop and soil properties. The land was prepared and divided into 12 treatments, each of 48 square meters on the first of April. Tomato seedlings were planted on 25 April 2010;the seedlings were irrigated with fresh water for a period of 10 days after planting. Three levels of saline water irrigation (3, 5, 7 dS/m) plus fresh water as control were applied during the growing season. The four irrigation water treatments were applied through three irrigation intervals (every day, every second day and every three days). Gravimetric soil moisture content and soil electrical conductivity were monitored every two weeks during the growing period. Yield measurements were taken for total fruit yield, marketable yield as a percent of total yield, and average fruit weight of each treatment. Results of this study indicated that, plant treatments irrigated with saline water gave the highest yield for treatments irrigated every day compared to the treatments irrigated every second day and every three days. Statistical analysis showed significant differences in yield reduction between every second day and every three days irrigation intervals under 5 and 7 dS/m saline irrigation levels, while there was no significant difference between irrigation intervals under 3 dS/m salinity level. 展开更多
关键词 SALINE Water IRRIGATION intervAL Soil TOMATO Electrical CONDUCTIVITY
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Two-agent single machine scheduling with forbidden intervals 被引量:1
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作者 FENG Qi LI Shi-sheng SHANG Wei-ping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第1期93-101,共9页
We consider the resumable version of the two-agent single machine scheduling prob- lems with forbidden intervals in which the jobs cannot be processed. The goal is to minimize the sum of the objective functions of the... We consider the resumable version of the two-agent single machine scheduling prob- lems with forbidden intervals in which the jobs cannot be processed. The goal is to minimize the sum of the objective functions of the two agents. Polynomial and pseudo-polynomial time algorithms are presented for various combinations of regular scheduling objective functions. 展开更多
关键词 two-agent scheduling dynamic programming forbidden interval.
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The AMSAA-BISE Model with Gap Intervals 被引量:1
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作者 Zhou Yuanquan and Weng Zhaoxi(Beijing Institute of Structure and Environment) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1990年第1期77-83,共7页
In this paper, the AMSAA-BISE model with missing data is discussed. The ML estimates of model parameters and current MTBF are given, and the chi-squared test and a plot for cumulative number of failures versus cumulat... In this paper, the AMSAA-BISE model with missing data is discussed. The ML estimates of model parameters and current MTBF are given, and the chi-squared test and a plot for cumulative number of failures versus cumulative testing time are used to test the goodness of fit for the model. This paper concludes with a numerical example to verify the model. 展开更多
关键词 Reliability growth Gap interval Missing data AMSAA-BISE model.
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Moved Score Confidence Intervals for Means of Discrete Distributions 被引量:1
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作者 Yu Guan 《Open Journal of Statistics》 2011年第2期81-86,共6页
Let X denote a discrete distribution as Poisson, binomial or negative binomial variable. The score confidence interval for the mean of X is obtained based on inverting the hypothesis test and the central limit theorem... Let X denote a discrete distribution as Poisson, binomial or negative binomial variable. The score confidence interval for the mean of X is obtained based on inverting the hypothesis test and the central limit theorem is discussed and recommended widely. But it has sharp downward spikes for small means. This paper proposes to move the score interval left a little (about 0.04 unit), called by moved score confidence interval. Numerical computation and Edgeworth expansion show that the moved score interval is analogous to the score interval completely and behaves better for moderate means;for small means the moved interval raises the infimum of the coverage probability and improves the sharp spikes significantly. Especially, it has unified explicit formulations to compute easily. 展开更多
关键词 CONFIDENCE intervAL CONFIDENCE Level COVERAGE PROBABILITY DISCRETE Distribution Moved SCORE CONFIDENCE intervAL
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Establishment of Reference Intervals and Transfusion Criterion for Sonoclot Analysis 被引量:2
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作者 张真路 陈佑平 +3 位作者 陶翠华 刘晓辉 李梦雅 周新 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2016年第4期614-617,共4页
Sonoclot analyzer has been widely used in many countries. But the reference intervals provided by the manufacturer were derived from only 45 participants, and there was no cut-off value for transfusion for Sonoclot an... Sonoclot analyzer has been widely used in many countries. But the reference intervals provided by the manufacturer were derived from only 45 participants, and there was no cut-off value for transfusion for Sonoclot analysis. This study aimed to establish reference intervals and transfusion criterion for Sonoclot analysis. Volunteers were recruited from healthy Chinese adults and patients undergoing cardiac surgery. Blood samples were withdrawn from forearm vein and measured for activated clotting time(ACT), clot rate(CR), platelet function(PF), activated partial thromboplastin time(APTT), fibrinogen concentration(FIB), and platelet count(PLT). The reference intervals were determined by the nonparametric method. Cut-off values were determined by the receiver operating characteristics curve. A total of 135 healthy volunteers and 281 patients were enrolled. The 95% reference intervals were 96–195 s, 22–51 signal U/min, 〉1.6 for ACT, CR, PF respectively. In the 281 patients, the results of APTT, FIB, PLT, ACT, CR, and PF ranged from 20.5–300.0 s, 0.28–4.11 g/L,(19.0–387.3)×109/L, 80–514 s, 2.9–74 signal U/min, and 0.1–5.1 respectively. The cut-off values for transfusion were 〉208, ≤14, and ≤1.3 for ACT, CR, PF respectively. The cut-off values of Sonoclot analysis were within the manufacturer's reference intervals, while they were outside the reference intervals established in this study. The results suggested that the manufacturer's reference intervals were not suitable for Chinese. The reference intervals and cut-off values established in this study will be helpful to Chinese patients. 展开更多
关键词 Sonoclot analyzer reference interval transfusion criterion
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Bootstrap Confidence Intervals for Proportions of Unequal Sized Groups Adjusted for Overdispersion 被引量:1
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作者 Olivia Wanjeri Mwangi Ali Islam Orawo Luke 《Open Journal of Statistics》 2015年第6期502-510,共9页
Group testing is a method of pooling a number of units together and performing a single test on the resulting group. It is an appealing option when few individual units are thought to be infected leading to reduced co... Group testing is a method of pooling a number of units together and performing a single test on the resulting group. It is an appealing option when few individual units are thought to be infected leading to reduced costs of testing as compared to individually testing the units. Group testing aims to identify the positive groups in all the groups tested or to estimate the proportion of positives (p) in a population. Interval estimation methods of the proportions in group testing for unequal group sizes adjusted for overdispersion have been examined. Lately improvement in statistical methods allows the construction of highly accurate confidence intervals (CIs). The aim here is to apply group testing for estimation and generate highly accurate Bootstrap confidence intervals (CIs) for the proportion of defective or positive units in particular. This study provided a comparison of several proven methods of constructing CIs for a binomial proportion after adjusting for overdispersion in group testing with groups of unequal sizes. Bootstrap resampling was applied on data simulated from binomial distribution, and confidence intervals with high coverage probabilities were produced. This data was assumed to be overdispersed and independent between groups but correlated within these groups. Interval estimation methods based on the Wald, the Logit and Complementary log-log (CLL) functions were considered. The criterion used in the comparisons is mainly the coverage probabilities attained by nominal 95% CIs, though interval width is also regarded. Bootstrapping produced CIs with high coverage probabilities for each of the three interval methods. 展开更多
关键词 Group Testing Overdispersion QUASI-LIKELIHOOD CONFIDENCE interval BOOTSTRAPPING COVERAGE Probability
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Rules for confidence intervals of permeability coefficients for water flow in over-broken rock mass 被引量:7
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作者 Liu Weiqun Fei Xiaodong Fang Jingnian 《International Journal of Mining Science and Technology》 2012年第1期29-33,共5页
Based on the steady-state seepage method, we used the Mechanical Testing and Simulation 815.02 System and a self-designed seepage instrument for over-broken stone to measure seepage properties of water flows in three ... Based on the steady-state seepage method, we used the Mechanical Testing and Simulation 815.02 System and a self-designed seepage instrument for over-broken stone to measure seepage properties of water flows in three types of crushed rock samples. Three methods of confidence interval in describing permeability coefficients are presented: the secure interval, the calculated interval and the systemic interval. The lower bound of the secure interval can be applied to water-inrush and the upper bound can solve the problem of connectivity. For the calculated interval, as the axial pressure increases, the length of confidence interval is shortened and the upper and lower bounds are reduced. For the systemic interval, the length of its confidence interval, as well as the upper and lower bounds, clearly vary under low axial pressure but are fairly similar under high axial pressure. These three methods provide useful information and references for analyzing the permeability coefficient of over-broken rock. 展开更多
关键词 置信区间 渗透系数 破碎岩体 水流 力学性能测试 时间间隔 轴向压力 安全间隔
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