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Characteristics of Infertile Clientele Attending a Public in Vitro Fertilization Clinic: Appraising Priorities in a Low-Income Country
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作者 Gbolahan O. Obajimi Olugbenga O. Saanu +2 位作者 Ayodeji S. Adeyanju Ademola S. Olutoye Mofiyinfoluwa M. Adeyeye 《Open Journal of Epidemiology》 2024年第2期343-352,共10页
Introduction: Infertilityaffects one in six couples, and it is an important public health issue largely due to thepervasive effects on the emotional and psychological wellbeing of affected couples. In many developing ... Introduction: Infertilityaffects one in six couples, and it is an important public health issue largely due to thepervasive effects on the emotional and psychological wellbeing of affected couples. In many developing nations emphasis is placed on childbirth and inability to fulfill this role can be very distressing. There is an unmet need for assisted reproductive technology (ART) in many developing countries and where facilities exist, they are mostly privately owned, expensive and concentrated in urban areas. To bridge this gap, public fertility clinics have been established to provide subsidized care. Evaluating the characteristics and peculiarities of clientele presenting at these public facilities will aid planning and prioritization of care. Methodology: A descriptive retrospective study of 116 infertile patients presenting to the fertility clinic of the University College Hospital, Ibadan, Nigeria from inception on the 14<sup>th</sup> of February 2019 and 31<sup>st</sup> of December 2022.Data was analyzed using the Statical Package for Social Sciences (IBM, SPSS, New York) version 23. Descriptive statistics were used to summarize the results which were presented with the aid of bar charts and frequency tables. Result: The mean age of the patients was 40.70 ± 6.62 years. Post-menopausal patients accounted for about one-fifth of the study population while 80.2% (93 women) were older than 35 years. The mean duration of infertility was 9.39 ± 6.11years and nine patients (7.8%) had a duration greater than 2 decades. Secondary infertility occurred in 67.2% of the women. Twenty-nine women (25%) had undergone myomectomy prior to presentation. Hypertension (11.2%) was the most prevalent comorbidity. Nineteen patients (16.4%) had used contraceptives in the past with the male condom (36.8%)being the most preponderant. Sixty-seven patients had experienced pregnancy losses before 28 weeks of gestation while just 16 patients (13.8%) had undergone ART, and none was successful. Conclusion: Secondary infertility was the prevalent type of infertility and may not be unconnected with the low contraceptive usage and high risk of sexually transmitted infection. Late presentation coupled with a large proportion of post-menopausal clientele suggests delayed health-seeking behavior most probably due to the prohibitive cost of ART. The need to streamline services offered in public fertility clinics is paramount in low-income countries grappling with scarce resources. A pragmatic approach will involve the provision of low-cost ART, while enhancing gamete donation programs through the implementation of gamete sharing policies. This will invariably bridge the unmet need and skewed access to ART in developing countries. 展开更多
关键词 INFERTILITY Assisted Reproductive Technology LOW-INCOME priorities.
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COMRADES FOREVER--To Lam’s visit demonstrates that China remains Vietnam’s top foreign policy priority
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作者 Yang Danzhi 《China Report ASEAN》 2024年第8期30-31,共2页
On August 20,2024,General Secretary of the Communist Party of Vietnam(CPV)Central Committee and Vietnamese President To Lam concluded his state visit to China.China was the destination for Lam's first overseas vis... On August 20,2024,General Secretary of the Communist Party of Vietnam(CPV)Central Committee and Vietnamese President To Lam concluded his state visit to China.China was the destination for Lam's first overseas visit after taking office as general secretary of the CPV Central Committee,which clearly demonstrates that the heads of both countries attach importance to developing the bilateral relations and that Vietnam regards China as the strategic choice and top priority for its foreign policy. 展开更多
关键词 policy VIETNAM priority
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Applying an Ordinal Priority Approach Based Neutrosophic Fuzzy Axiomatic Design Approach to Develop Sustainable Geothermal Energy Source
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作者 Chia-Nan Wang Thuy-Duong Thi Pham Nhat-Luong Nhieu 《Energy Engineering》 EI 2024年第8期2039-2064,共26页
Geothermal energy is considered a renewable,environmentally friendly,especially carbon-free,sustainable energy source that can solve the problem of climate change.In general,countries with geothermal energy resources ... Geothermal energy is considered a renewable,environmentally friendly,especially carbon-free,sustainable energy source that can solve the problem of climate change.In general,countries with geothermal energy resources are the ones going through the ring of fire.Therefore,not every country is lucky enough to own this resource.As a country with 117 active volcanoes and within the world’s ring of fire,it is a country whose geothermal resources are estimated to be about 40%of the world’s geothermal energy potential.However,the percentage used compared to the geothermal potential is too small.Therefore,this is the main energy source that Indonesia is aiming to exploit and use.However,the deployment and development of this energy source are still facing many obstacles due to many aspects from budget sources due to high capital costs,factory construction location,quality of resources,and conflicts of the local community.In this context,determining the optimal locations for geothermal energy sites(GES)is one of the most important and necessary issues.To strengthen the selection methods,this study applies a two-layer fuzzy multi-criteria decision-making method.Through the layers,the Ordinal Priority Approach(OPA)is proposed to weight the sub-criteria,the main criterion,and the sustainability factors.In layer 2,the Neutrosophic Fuzzy Axiomatic Design(NFAD)is applied to rank and evaluate potential locations for geothermal plant construction.Choosing the right geothermal energy site can bring low-cost efficiency,no greenhouse gas emissions,and quickly become the main energy source providing electricity for Indonesia.The final ranking shows Papua,Kawah Cibuni,and Moluccas as the three most suitable cities to build geothermal energy systems.Kawah Cibuni was identified as the most potential GES in Indonesia,with a score of 0.46.Papua is the second most promising GES with a score of 0.45.Next is the Moluccas,with a score of 0.39.However,the three least potential sites among the 15 studied sites are Lumut Balai,Moluccas and Patuha,with scores of 0.08,0.11 and 0.17,respectively.The conclusion of this study also classifies positions into groups to aid in decision-making. 展开更多
关键词 Ordinal priority approach neutrosophic fuzzy axiomatic design renewable energy multiple criteria decision making geothermal energy
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Shape Analysis of Agricultural Parcels for Land Consolidation Priorities in Tekirdag Province,Turkey
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作者 Bahadir ALTURK 《Chinese Geographical Science》 SCIE CSCD 2024年第1期93-105,共13页
Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significan... Shape irregularity,a sub-factor of parcel fragmentation is a problem that hinders sustainable agriculture and is solved using land consolidation projects.Determination of the parcel shape degree contributes significantly to spatial prioritization where there is also a high probability of achieving positive effects of consolidation projects.This study aims to determine the shape degree of the agricultural parcels both at singular and rural county scales in Tekirdag Province,Turkey in 2020 by combining the parcel shape index(PSI) with the minimum bounding geometry index(MBG) to improve parcel scores.Hot-spot zones of the highly irregular and near optimum parcels were also determined using Getis-Ord G_(i)^(*) statistic.The parcel degrees were classified into four categories,namely highly irregular,irregular,regular and near optimum.The obtained unweighted scores of the parameters exhibit deviations from the expected values.After weighting by pairwise comparison,the values approached ideal scores.Among 346 740 parcels,53% were highly irregular and irregular and 47% were regular and near optimum shapes after weighting whereas these were 70% and 30%,respectively before weighting.The average parcel degree of 63 rural counties was regular while the average parcel degree of the remaining 264 rural counties was irregular.The combined use of PSI and MBG index improved the correctness of the parcel shape score.It could be suggested to use as a tool in land consolidation prioritization. 展开更多
关键词 land consolidation priority parcel shape index(PSI) minimum bounding geometry(MBG) sustainable rural development hot-spot analysis Tekirdag Province TURKEY
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A priority-based electric vehicle-assisted grid frequency regulation system
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作者 LI Xuancheng QIN Jin +1 位作者 QIN Huibin HUA Yongzhu 《High Technology Letters》 EI CAS 2024年第4期397-404,共8页
During electric vehicle(EV)-assisted grid frequency modulation,inconsistent state of charge(SOC)among EVs can result in overcharging and discharging of the batteries,affecting the stability of the electrical system.As... During electric vehicle(EV)-assisted grid frequency modulation,inconsistent state of charge(SOC)among EVs can result in overcharging and discharging of the batteries,affecting the stability of the electrical system.As a solution,this paper proposes a priority-based frequency regulation strategy for EVs.Firstly,models for the primary and secondary frequency regulation of EV-assisted power grids are established.Secondly,a consensus algorithm is used to construct a distributed com-munication system for EVs.Target SOC values are used to obtain a local frequency regulation priori-ty list.The list is used in an optimal control plan allowing individual EVs to participate in frequency regulation.Finally,a simulation of this strategy under several scenarios is conducted.The results indicate that the strategy ensures uniform SOC among the participating group of EVs,thereby avoi-ding overcharging and discharging of their batteries.It also reduces frequency fluctuations in the electrical system,making the system more robust compared with the frequency regulation strategy that is not priority-based. 展开更多
关键词 grid frequency regulation electric vehicle(EV) state of charge(SOC)consisten-cy priority distributed energy storage system
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一种融合Priority-Flood算法与D8算法特点的河网提取方法 被引量:8
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作者 卢庆辉 熊礼阳 +2 位作者 蒋如乔 巫晓玲 段家朕 《地理与地理信息科学》 CSCD 北大核心 2017年第4期40-46,共7页
基于数字高程模型(Digital Elevation Models)进行河网提取是数字地形分析的重要研究内容和水文分析的关键步骤,而流向算法是其中最重要的部分。然而,传统的流向算法在平坦地形区域容易形成平行河网。为解决平行河网问题,该文提出了一... 基于数字高程模型(Digital Elevation Models)进行河网提取是数字地形分析的重要研究内容和水文分析的关键步骤,而流向算法是其中最重要的部分。然而,传统的流向算法在平坦地形区域容易形成平行河网。为解决平行河网问题,该文提出了一种结合Priority-Flood算法漫水思想和改进D8算法的流向算法。借助Priority-Flood算法的漫水思想,可以保证流向符合宏观地形特征;同时将地形划分为上坡、平地和下坡3种类型,辅以PriorityFlood算法可以实现在不填洼的基础上计算流向,而且针对不同地形,采用相应的改进D8流向算法,从而保证流向符合微观地形特征。通过这两种算法的结合,可以直接使用原始DEM提取河网,消除了填洼过程,提高了流向计算效率,同时消除了填洼造成的大量平地,有效地解决了平地区域平行河网问题。最后,选取全球不同区域SRTM数据对J&D算法与新算法进行对比实验,结果表明,新算法能够有效地改善平行河网问题。 展开更多
关键词 河网提取 priority2Flood算法 D8算法 平行河网 流向算法
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Priority approach based on quadratic programming model to fuzzy preference relation 被引量:1
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作者 徐泽水 达庆利 陈琦 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期108-110,共3页
We investigate the decision-making problem with a finite set of alternatives,in which the decision information takes the form of a fuzzy preference relation. We develop asimple and practical approach to obtaining the ... We investigate the decision-making problem with a finite set of alternatives,in which the decision information takes the form of a fuzzy preference relation. We develop asimple and practical approach to obtaining the priority vector of a fuzzy preference relation. Theprominent characteristic of the developed approach is that the priority vector can generally beobtained by a simple formula, which is derived from a quadratic programming model. We utilize theconsistency ratio to check the consistency of fuzzy preference relation. If the fuzzy preferencerelation is of unacceptable consistency, then we can return it to the decision maker to reconsiderstructuring a new fuzzy preference relation until the fuzzy preference relation with acceptableconsistency is obtained. We finally illustrate the priority approach by two numerical examples. Thenumerical results show that the developed approach is straightforward, effective, and can easily beperformed on a computer. 展开更多
关键词 decision making fuzzy preference relation quadratic programming priority
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On Application of Nida’s Priorities in Translation 被引量:1
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作者 杨丹宇 《内蒙古师范大学学报(哲学社会科学版)》 2001年第S1期47-49,共3页
This paper analyzes Nida’s theory of translation, also his system of priorities. The paper uses examples to illustrate the application of Nida’s four priorities in the practice of English Chinese and Chinese English... This paper analyzes Nida’s theory of translation, also his system of priorities. The paper uses examples to illustrate the application of Nida’s four priorities in the practice of English Chinese and Chinese English translation and concludes that we can apply the system to help the receptors of second language and source language to have the closest response. 展开更多
关键词 priorities TRANSLATION PRACTICE
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Multi-phase bus signal priority strategy at isolated intersections
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作者 王琳虹 别一鸣 +1 位作者 王殿海 宋现敏 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期430-435,共6页
To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought fo... To satisfy the multiple priority requests from buses that arrive at different phases within a small time window, a multi-phase bus signal priority (MPBSP) strategy is developed. The proximity principle is brought forward to settle the conflicts among multiple priority requests and arrange the optimal priority sequence. To avoid over saturation of the intersection, a conditional MPBSP algorithm that adopts early green and green extension strategies is developed to give priority to the bus with the highest priority level when green time that each phase runs makes its saturation degree not larger than 0. 95. Finally, the algorithm is tested in the VISSIM environment and compared with the normal signal timing algorithm. Sensitive analysis of the number of priority phases, bus demand, and volume to capacity ratios are conducted to quantify their impacts on the benefits of the MPBSP. Results show that the MPBSP strategy can effectively reduce bus delays, and with the increase in the number of priority phases, the reduction range of bus delays also increases. 展开更多
关键词 bus signal priority multiple phases early green green extension isolated intersection
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基于多PRI脉压回波的单通道雷达干扰分离方法 被引量:1
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作者 刘梅 杨威 +1 位作者 高勋章 刘永祥 《信息对抗技术》 2024年第1期70-80,共11页
研究了一种基于盲源分离的单通道雷达有源相干干扰抑制方法。针对伴随式干扰场景,在间歇采样转发干扰、部分脉冲密集转发干扰等有源相干干扰并存的条件下,建立了基于脉冲压缩的多脉冲重复间隔采样抗主瓣有源相干干扰模型并对其可行性进... 研究了一种基于盲源分离的单通道雷达有源相干干扰抑制方法。针对伴随式干扰场景,在间歇采样转发干扰、部分脉冲密集转发干扰等有源相干干扰并存的条件下,建立了基于脉冲压缩的多脉冲重复间隔采样抗主瓣有源相干干扰模型并对其可行性进行了证明。针对现有单通道盲源分离方法在时域进行分离效果有限的问题,提出对脉压后的距离维数据进行盲源分离的思想,可在一定程度上抑制噪声对盲源分离的影响。同时,由于目标信号和干扰信号在脉冲压缩后重合度较低,可获得更好的分离效果。仿真和实测结果表明,在多个干扰源存在的条件下,本方法可有效分离真实目标回波和干扰回波。当信噪比大于5 dB时,目标脉压回波相似系数接近100%;选取虚拟通道数越多,分离效果越好。 展开更多
关键词 单通道盲分离 pri采样 抗主瓣有源干扰 最小描述长度准则
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基于时频域特征挖掘与自注意力机制融合的雷达PRI变化类型识别
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作者 王军 薛磊 +2 位作者 屠俑霖 遇浩宁 姜建华 《信息对抗技术》 2024年第5期74-83,共10页
针对存在异常值时雷达辐射源脉冲重复间隔(pulse repetition interval,PRI)变化类型识别困难的问题,提出一种基于时频域特征挖掘与自注意力机制融合的雷达PRI变化类型识别方法。首先对PRI序列进行时序变化特征和小波特征分析,从时域和频... 针对存在异常值时雷达辐射源脉冲重复间隔(pulse repetition interval,PRI)变化类型识别困难的问题,提出一种基于时频域特征挖掘与自注意力机制融合的雷达PRI变化类型识别方法。首先对PRI序列进行时序变化特征和小波特征分析,从时域和频域2个角度构建特征集;然后基于自注意力机制以数据驱动的方式学习时频特征之间的互补性,有效把握不同维度特征对识别效果的贡献,实现对不同维度特征的深度融合;最后基于全连接神经网络对融合后的特征进行模式分类,从而实现对PRI变化类型的识别。仿真结果表明,在不同异常值水平下,所提方法能够显著提高对6种典型PRI变化类型的识别准确率,而且识别效果要显著优于仅使用单一维度特征的方法。 展开更多
关键词 时频域特征挖掘 小波变换 自注意力机制 神经网络 pri变化类型识别
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On Priority of “Meaning” in Translation
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作者 贾青萍 《科技信息》 2010年第35期J0284-J0284,J0434,共2页
In this paper the author expounded the term "meaning" from the perspectives of semantics,semiotics and pragmatics and talked about the importance and priority of "meaning" in translation.
关键词 英语学习 学习方法 阅读 翻译
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RESEARCH ON WEIGHTED PRIORITY OF EXEMPLAR-BASED IMAGE INPAINTING 被引量:28
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作者 Zhou Yatong Li Lin Xia Kewen 《Journal of Electronics(China)》 2012年第1期166-170,共5页
The priority of the filled patch play a key role in the exemplar-based image inpainting, and it should be determined firstly to optimize the process of image inpainting. A modified image inpainting algorithm is propos... The priority of the filled patch play a key role in the exemplar-based image inpainting, and it should be determined firstly to optimize the process of image inpainting. A modified image inpainting algorithm is proposed by weighted-priority based on the Criminisi algorithm. The improved algorithm demonstrates better relationship between the data term and the confidence term for the optimization of the priority than the classical Criminisi algorithm. By comparing the effect of the inpainted images with different structure, conclusion can be drawn that the optimal priority should be chosen properly for different images with different structures. 展开更多
关键词 Image inpainting Exemplar-based Data term priority Weight
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New approach to determine the priorities from interval fuzzy preference relations 被引量:7
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作者 Qi Yue Zhiping Fan Lihua Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期267-273,共7页
An approach is proposed to solve the problem how to obtain the priorities from interval fuzzy preference relations. Firstly, another expression of interval numbers is given. Then, some basic definitions on consistency... An approach is proposed to solve the problem how to obtain the priorities from interval fuzzy preference relations. Firstly, another expression of interval numbers is given. Then, some basic definitions on consistency and weak transitivity of real and interval fuzzy preference relations are described. Based on these definitions, a two-phase process for determining the priorities from interval fuzzy preference relations is presented. Finally, two exam- ples are used to illustrate the use of the proposed approach. 展开更多
关键词 interval fuzzy preference relation CONSISTENCY weaktransitivity priority.
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Dynamic channel reservation scheme based on priorities in LEO satellite systems 被引量:8
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作者 Jian Zhou Xiaoguo Ye +2 位作者 Yong Pan Fu Xiao Lijuan Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期1-9,共9页
According to low earth orbit(LEO) satellite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresholds for reserved channels i... According to low earth orbit(LEO) satellite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresholds for reserved channels is the key of this strategy. In order to obtain the optimal thresholds, the traffic is predicted based on the high-speed deterministic movement property of LEO satellites firstly. Then, a channel allocation model based on Markov is established. Finally, the solution of the model is obtained based on the genetic algorithm. Without user location, this strategy effectively reduces handover failures and improves channel utilization by adjusting dynamically the thresholds according to traffic conditions. The simulation results show that the system's overall quality of service can be improved by this strategy. 展开更多
关键词 dynamic channel reservation priority HANDOVER different level user low earth orbit(LEO)
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Determination of surgical priorities in appendicitis based on the probability of undetected appendiceal perforation 被引量:2
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作者 Sang Chul Lee Geon Park +1 位作者 Byung-Jo Choi Say-June Kim 《World Journal of Gastroenterology》 SCIE CAS 2015年第7期2131-2139,共9页
AIM:To identify risk factors of actual appendiceal perforation when computed tomography(CT)scans suggest nonperforated appendicitis and accordingly determine surgical priority.METHODS:We collected database of 1362 pat... AIM:To identify risk factors of actual appendiceal perforation when computed tomography(CT)scans suggest nonperforated appendicitis and accordingly determine surgical priority.METHODS:We collected database of 1362 patients who underwent an appendectomy for acute appendicitis between 2006 and 2013.A single radiologist selected1236 patients whose CT scans were suggestive ofnonperforated appendicitis.Patients were divided into 2 groups:actual nonperforation group and actual perforation group according to intraoperative and pathologic features.Comparison of the 2 groups were made using binary logistic regression.RESULTS:Of 1236 patients,90(7.3%)were found to have actual appendiceal perforation.Four risk factors related with actual appendiceal perforation were identified:body temperature≥37.6℃(HR=1.912,95%CI:1.161-3.149;P=0.011),out-ofhospital symptom duration≥72 h(HR=2.454,95%CI:1.292-4.662;P=0.006),age≥35 years(HR=3.358,95%CI:1.968-5.728;P<0.001),and appendiceal diameter on CT scan≥8 mm(HR=4.294,95%CI:1.034-17.832;P=0.045).Actual appendiceal perforation group showed longer operation time,later initiation of diet,longer use of parenteral narcotics,longer hospital stay,and higher incidence of postoperative complications(P<0.05).CONCLUSION:We proposed here new criteria to select patients with adverse clinical outcomes after appendectomy among the patients with radiologically nonperforated appendicitis.Surgical appendectomy outcomes could be improved by determining the surgical priority according to our criteria. 展开更多
关键词 APPENDICITIS APPENDICEAL PERFORATION OPERATIVE pri
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Strategic Priority Program on Space Science 被引量:3
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作者 WU Ji SUN Lilin 《空间科学学报》 CAS CSCD 北大核心 2014年第5期505-515,共11页
In 1957, the launch of the first artificial satellite ushered in a new era for modern space science. The past 50 years' developments in China's space science have witnessed many major missions, and substantial... In 1957, the launch of the first artificial satellite ushered in a new era for modern space science. The past 50 years' developments in China's space science have witnessed many major missions, and substantial progress has been achieved in space science study, exploration technology as well as experiment technology. Strategic Priority Program on Space Science was officially started in 2011. Through both self-developed space science missions and those with international cooperation,it is expected that the innovative breakthroughs will be realized, leapfrog development of related high-tech will be achieved to establish the important strategic status of space science in national development. To sum up, the implementation of the Strategic Priority Program on Space Science will definitely promote the rapid development of China's space science endeavor, making contributions to China's development and the progress of human civilization. 展开更多
关键词 STRATEGIC priority PROGRAM on Space SCIENCE SCIENCE objectives PAYLOAD STATUS
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A Hybrid Model Predictive Control for Handling Infeasibility and Constraint Prioritization 被引量:4
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作者 王宇红 黄德先 金以慧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第2期211-217,共7页
A hybrid approach using MLD (mixed logical dynamical) framework to handle infeasibility and constraint prioritization issues in MPC (model predictive control) based on input-output model is introduced. By expressing c... A hybrid approach using MLD (mixed logical dynamical) framework to handle infeasibility and constraint prioritization issues in MPC (model predictive control) based on input-output model is introduced. By expressing constraint priorities as propositional logics and by transforming the propositional logics into inequalities,the infeasibility and constraint prioritization issues are solved in the MPC. Constraints with higher priorities are met first, and then these with lower priorities are satisfied as much as possible. This new approach is illustrated in the control of a heavy oil fractionator-Shell column. The overall control performance has been significantly improved through the infeasibility and control priorities handling. 展开更多
关键词 model predictive control FEASIBILITY mixed logical dynamical system priority hybrid system
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Design of task priority model and algorithm for imaging observation problem 被引量:2
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作者 WU Jian LU Fang +2 位作者 ZHANG Jiawei YANG Jinghui XING Lining 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第2期321-334,共14页
In the imaging observation system, imaging task scheduling is an important topic. Most scholars study the imaging task scheduling from the perspective of static priority, and only a few from the perspective of dynamic... In the imaging observation system, imaging task scheduling is an important topic. Most scholars study the imaging task scheduling from the perspective of static priority, and only a few from the perspective of dynamic priority. However,the priority of the imaging task is dynamic in actual engineering. To supplement the research on imaging observation, this paper proposes the task priority model, dynamic scheduling strategy and Heuristic algorithm. At first, this paper analyzes the relevant theoretical basis of imaging observation, decomposes the task priority into four parts, including target priority, imaging task priority, track, telemetry & control(TT&C)requirement priority and data transmission requirement priority, summarizes the attribute factors that affect the above four types of priority in detail, and designs the corresponding priority model. Then, this paper takes the emergency tasks scheduling problem as the background, proposes the dynamic scheduling strategy and heuristic algorithm. Finally, the task priority model,dynamic scheduling strategy and heuristic algorithm are verified by experiments. 展开更多
关键词 IMAGING OBSERVATION system IMAGING TASK priority TASK priority model dynamic SCHEDULING strategy HEURISTIC algorithm
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Priority recovery of lithium and effective leaching of nickel and cobalt from spent lithium-ion battery 被引量:5
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作者 Ning CAO Ya-li ZHANG +2 位作者 Lin-lin CHEN Yun JIA Yao-guo HUANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第5期1677-1690,共14页
The cathode materials of spent lithium-ion batteries(LIBs)were recovered via reductive roasting,Na_(2)CO_(3) leaching,and ammonia leaching.The effects of roasting parameters,Na_(2)CO_(3) leaching parameters,and ammoni... The cathode materials of spent lithium-ion batteries(LIBs)were recovered via reductive roasting,Na_(2)CO_(3) leaching,and ammonia leaching.The effects of roasting parameters,Na_(2)CO_(3) leaching parameters,and ammonia leaching parameters on the leaching efficiencies of metals were explored.The results show that the mineral phase of spent LIBs is reconstructed during reductive roasting,and more than 99%of Li can be preferentially leached via Na_(2)CO_(3) leaching.Ni(99.7%)and Co(99.9%)can be leached via one-step ammonia leaching,and Mn cannot be leached.Thus,good leaching selectivity is achieved.The kinetic study shows that the leaching of Ni and Co conforms to chemical reaction control. 展开更多
关键词 LITHIUM priority recovery reductive roasting ammonia leaching spent lithium-ion battery
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