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Changes in Cooking and Nutrition Qualities of Grains at Different Positions in a Rice Panicle under Different Nitrogen Levels 被引量:15
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作者 DONG Ming-hui SANG Da-zhi WANG Peng WANG Xue-ming YANG Jian-chang 《Rice science》 SCIE 2007年第2期141-148,共8页
Cooking and nutrition qualities of grain are two of the most important aspects of rice quality. To understand the difference in cooking and nutrition qualities among the grains at different positions within a rice pan... Cooking and nutrition qualities of grain are two of the most important aspects of rice quality. To understand the difference in cooking and nutrition qualities among the grains at different positions within a rice panicle, the distributions of gel consistency (GC), amylose content (AC) and crude protein content (CPC) of grains in a panicle in association with different nitrogen levels (0, 120 and 240 k c/ha) were investigated by using two rice varieties, Yangdao 6 (indica) and Wuyujing 3 (japonica). In general, the grains at the basal part of a panicle had lower GC and higher AC than those at the upper or middle part of a panicle. The 1^st grain on the secondary branch with earlier flowering exhibited the highest GC, whereas the 2nd grain on the primary branch with later flowering showed the highest AC. For Yangdao 6, CPC in the grains on the primary branches was lower at the middle part of a panicle than at the upper or basal part of a panicle. For Wuyujing 3, there were no significant differences in CPCs in the grains among the upper, middle and basal parts of a panicle. GC in the grains was increased, whereas AC was reduced from zero nitrogen application (ON) to low amount of nitrogen application (LN), and the result was reversed from LN to medium amount of nitrogen application (MN). CPC was increased with the increase in the amount of nitrogen application. 展开更多
关键词 RICE grain position cooking quality nutrition quality NITROGEN
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Signal quality analysis and quality check of BDS3 Precise Point Positioning in the Arctic Ocean 被引量:1
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作者 Xiaoguo Guan Hongzhou Chai +3 位作者 Guorui Xiao Zhenqiang Du Wenlong Qi Xueping Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第2期166-179,共14页
This study analyzes the signal quality and the accuracy of BeiDou 3 rd generation Satellite Navigation System(BDS3) Precise Point Positioning(PPP) in the Arctic Ocean. Assessment of signal quality of BDS3 includes sig... This study analyzes the signal quality and the accuracy of BeiDou 3 rd generation Satellite Navigation System(BDS3) Precise Point Positioning(PPP) in the Arctic Ocean. Assessment of signal quality of BDS3 includes signal to noise ratio(SNR), multipath(MP), dilution of precision(DOP), and code-minus-carrier combination(CC). The results show that, 5 to 13 satellites are visible at any time in the Arctic Ocean area as of September 2018, which are sufficient for positioning. In the mid-latitude oceanic region and in the Arctic Ocean, the SNR is 25–52 dB Hz and the MP ranges from-2 m to 2 m. As the latitude increases, the DOP values show large variation, which may be related to the distribution of BDS satellites. The CC values of signals B1 I and BIC range from-5 m to 5 m in the mid-latitude sea area and the Arctic Ocean, which means the effect of pseudorange noise is small. Moreover, as to obtain the external precise reference value for GNSS positioning in the Arctic Ocean region is difficult, it is hard to evaluate the accuracy of positioning results. An improved isotropy-based protection level method based on Receiver Autonomous Integrity Monitoring is proposed in the paper, which adopts median filter to smooth the gross errors to assess the precision and reliability of PPP in the Arctic Ocean. At first, the improved algorithm is verified with the data from the International GNSS Service Station Tixi. Then the accuracy of BDS3 PPP in the Arctic Ocean is calculated based on the improved algorithm. Which shows that the kinematic accuracy of PPP can reach the decimeter level in both the horizontal and vertical directions, and it meets the precision requirements of maritime navigation. 展开更多
关键词 BDS3 Arctic Ocean signal quality analysis protection level quality check Precise Point positioning satellite navigation
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Effects of planting dates and shading on carbohydrate content,yield,and fiber quality in cotton with respect to fruiting positions 被引量:2
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作者 ZHAO Wen-qing WU You +5 位作者 Zahoor Rizwan WANG You-hua MA Yi-na CHEN Bing-lin MENG Ya-li ZHOU Zhi-guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第5期1106-1119,共14页
Two cotton(Gossypium hirsutum L.) cultivars, Kemian 1(cool temperature-tolerant) and Sumian 15(cool temperaturesensitive) were used to study the effects of cool temperature on carbohydrates, yield, and fiber qua... Two cotton(Gossypium hirsutum L.) cultivars, Kemian 1(cool temperature-tolerant) and Sumian 15(cool temperaturesensitive) were used to study the effects of cool temperature on carbohydrates, yield, and fiber quality in cotton bolls located at different fruiting positions(FP). Cool temperatures were created using late planting and low light. The experiment was conducted in 2010 and 2011 using two planting dates(OPD, the optimized planting date, 25 April; LPD, the late planting date, 10 June) and two shading levels of crop relative light rate(CRLR, 100 and 60%). Compared with fruiting position 1(FP1), cotton yield and yield components(fiber quality, leaf sucrose and starch content, and fiber cellulose) were all decreased on FP3 under all treatments. Compared with OPD-CRLR 100%, other treatments(OPD-CRLR 60%, LPD-CRLR 100%, and LPD-CRLR 60%) had significantly decreased lint yield at both FPs of both cultivars, but especially at FP3 and in Sumian 15; this decrease was mainly caused by a large decline in boll number. All fiber quality indices decreased under late planting and shading except fiber length at FP1 with OPD-CRLR 60%, and a greater reduction was observed at FP3 and in Sumian 15. Sucrose content of the subtending leaf and fiber increased under LPD compared to OPD, whereas it decreased under CRLR 60% compared to CRLR 100%, which led to decreased fiber cellulose content. Therefore, shading primarily decreased the "source" sucrose content in the subtending leaf whereas late planting diminished translocation of sucrose towards cotton fiber. Notably, as planting date was delayed and light was decreased, more carbohydrates were distributed to leaf and bolls at FP1 than those at FP3, resulting in higher yield and better fiber quality at FP1, and a higher proportion of bolls and carbohydrates allocated at FP3 of Kemian 1 compared to that of Sumian 15. In conclusion, cotton yield and fiber quality were reduced less at FP1 compared to those at FP3 under low temperature and low light conditions. Thus, reduced cotton yield and fiber quality loss can be minimized by selecting low temperature tolerant cultivars under both low temperature and light conditions. 展开更多
关键词 cotton planting date and shading fruiting position yield fiber quality
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Impact of web-based positive psychological intervention on emotions,psychological capital,and quality of life in gastric cancer patients on chemotherapy
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作者 Yu-Yu Xin Dan Zhao 《World Journal of Clinical Cases》 SCIE 2024年第26期5877-5884,共8页
BACKGROUND Gastric cancer is a malignant digestive tract tumor that originates from the epithelium of the gastric mucosa and occurs in the gastric antrum,particularly in the lower curvature of the stomach.AIM To evalu... BACKGROUND Gastric cancer is a malignant digestive tract tumor that originates from the epithelium of the gastric mucosa and occurs in the gastric antrum,particularly in the lower curvature of the stomach.AIM To evaluate the impact of a positive web-based psychological intervention on emotions,psychological capital,and quality of survival in gastric cancer patients on chemotherapy.METHODS From January 2020 to October 2023,121 cases of gastric cancer patients on chemotherapy admitted to our hospital were collected and divided into a control group(n=60)and an observation group(n=61)according to the admission order.They were given either conventional nursing care alone and conventional nursing care combined with web-based positive psychological interventions,respectively.The two groups were compared in terms of negative emotions,psychological capital,degree of cancer-caused fatigue,and quality of survival.RESULTS After intervention,the number of patients in the observation group who had negative feelings toward chemotherapy treatment was significantly lower than that of the control group(P<0.05);the Positive Psychological Capital Questionnaire score was considerably higher than that of the control group(P<0.05);the degree of cancer-caused fatigue was significantly lower than that of the control group(P<0.05);and the Quality of Life Scale for Cancer Patients(QLQ-30)score was significantly higher than that of the control group(P<0.05).CONCLUSION Implementing a web-based positive psychological intervention for gastric cancer chemotherapy patients can effectively improve negative emotions,enhance psychological capital,and improve the quality of survival. 展开更多
关键词 Internet positive psychology Gastric cancer chemotherapy Negative emotions Psychological capital quality of survival
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Effect of psychological nursing interventions on effectiveness and quality of life in schizophrenia patients receiving modified electroconvulsive therapy
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作者 Jing Lu 《World Journal of Clinical Cases》 SCIE 2024年第16期2751-2757,共7页
BACKGROUND Schizophrenia is a common and severe mental disorder characterized by severe thought disturbances,hallucinations,delusions,and emotional instability.For some patients,conventional treatment methods may not ... BACKGROUND Schizophrenia is a common and severe mental disorder characterized by severe thought disturbances,hallucinations,delusions,and emotional instability.For some patients,conventional treatment methods may not effectively alleviate symptoms,necessitating the use of alternative therapeutic approaches.Modified electroconvulsive therapy(MECT)is an effective treatment modality for schizophrenia,inducing anti-depressive and antipsychotic effects through the stimulation of brain electrical activity.AIM To explore the impact of psychological nursing intervention(PNI)before and after MECT on the efficacy and quality of life of patients with schizophrenia.METHODS Eighty patients with schizophrenia who received MECT treatment from 2021 to 2023 were randomly divided into two groups:The intervention group(n=40)and the control group(n=40).The intervention group received PNI before and after MECT,while the control group received routine nursing care.The efficacy of MECT was evaluated by the Positive and Negative Syndrome Scale(PANSS)and the Clinical Global Impression Scale(CGI)before and after the treatment.The quality of life was assessed by the Short Form 36 Health Survey(SF-36)after the treatment.RESUITS The intervention group had significantly lower scores of PANSS and CGI than the control group after the treatment(P<0.05).The intervention group also had significantly higher scores of SF-36 than the control group in all domains except physical functioning(P<0.05).CONCLUSION PNI before and after MECT can improve the efficacy and quality of life of patients with schizophrenia.It is suggested that nurses should provide individualized and comprehensive psychological care for patients undergoing MECT to enhance their recovery and well-being. 展开更多
关键词 Psychological nursing interventions Modified electroconvulsive therapy SCHIZOPHRENIA EFFICACY quality of life positive and negative syndrome scale
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An Application of Genetic Algorithm in Positioning Bricks
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作者 LUO Lin-kai, PENG Hong (Department of Automation, University of Xiamen, Xiamen 361005, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期268-,共1页
This note deals with how to position bricks so that m aximizing the numbers of whole brick in a given area. A method by genetic algori thm is given to solve this problem. By this method, the numbers of whole brick a n... This note deals with how to position bricks so that m aximizing the numbers of whole brick in a given area. A method by genetic algori thm is given to solve this problem. By this method, the numbers of whole brick a nd their position are gained when given areas are convex polygon and brick is re ctangular, and you can easily design a CAD soft to optimize the scheme of positi oning bricks. It is huge advantage by this method when given areas are nonregula r. Some rules of parameter’s influence to algorithm are pointed out by computer simulation. The first section states the problem and the math model of problem is given out. The second section gives out the solution by genetic algorithm, in cluding description of genetic algorithm and steps of algorithm about proble m of positioning bricks. The third section gives a computer simulation example. The last section is some discussions about this algorithm, including the influen ce of parameter to algorithm and optimizing parameter. Some rule is gained. 展开更多
关键词 genetic algorithm optimizing parameter position ing bricks
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Influence of Anthesis Date and Boll Branch Position on Qualities and Super-molecular Structure of Cotton Fiber
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作者 SHAN Shi-hua, SHI Pei, SUN Xue-zhen, ZHOU Zhi-guo and BIAN Dong-cai(Agronomy Department of Shandong Agricultural University, Taian 271018 , P. R . China Tianjin Institute of Textile , Tianjin 300160 , P.R. China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第6期636-641,共6页
The influences of the anthesis date and the fruiting branch positions on parameters of cotton fiber quality and super-molecular structure were studied. Fiber quality parameters, such as cotton fiber length, micronair,... The influences of the anthesis date and the fruiting branch positions on parameters of cotton fiber quality and super-molecular structure were studied. Fiber quality parameters, such as cotton fiber length, micronair, maturity and fiber strength deteriorated with postponing the anthesis date and decreasing temperature. When anthesis happened on the same date, the fruiting branch positions affected the fiber quality parameters, and the fiber quality parameters of the lower portion turned out to be higher than that of the upper portion, although the difference was insignificant. The super-molecular structure of the lower portion turned out to be superior to that of the upper portion at the early anthesis date and high temperature, which is in accordance with what was mentioned above, but the fruiting branch positions did not affect the impact of the anthesis date on the super-molecular structure. 展开更多
关键词 COTTON Anthesis date Fruiting branch positions Fiber qualities Super-molecular structure
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Effects of positive thinking intervention on negative emotions and quality of life in stroke patients:a scoping review
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作者 Xin Fan Mei Wang Xiang-Shu Cui 《Nursing Communications》 2023年第9期1-6,共6页
Objective:To analyze domestic and international studies on the effects of positive thought intervention therapy on negative emotions and the quality of life of stroke patients to provide a reference for future related... Objective:To analyze domestic and international studies on the effects of positive thought intervention therapy on negative emotions and the quality of life of stroke patients to provide a reference for future related studies.Methods:Using the scoping review method as a guide,computer searches of PubMed,Web of Science,Embase,Cochrane Library,China National Knowledge Infrastructure,Wanfang Database,China Vipers Full Text Database and China Biomedical Literature Database were conducted to collect relevant studies on the application of positive thinking interventions in stroke patients from the establishment to January 2023,and the literature was screened according to the inclusion and exclusion criteria,and the data were extracted and analyzed by two investigators independently.Results:The search yielded 964 publications,and a total of 19 were included.The time of publication,study site,study population,study design,study length,and type of results of the included studies was summarized and analyzed.Conclusions:Positive thinking-based interventions have shown significant changes in negative emotions such as anxiety and depression in stroke patients and can reduce somatic pain,enhance their social integration,and improve their quality of life.However,interventions in the areas of self-compassion,artificial intelligence and the adoption of tailoring need to be further explored. 展开更多
关键词 positive thinking intervention STROKE negative emotions quality of life scoping revie
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Using quality improvement methods to increase use of pain prevention strategies for childhood vaccination 被引量:3
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作者 Jennifer Verrill Schurman Amanda D Deacy +6 位作者 Rebecca J Johnson Jolynn Parker Kristi Williams Dustin Wallace Mark Connelly Lynn Anson Kevin Mroczka 《World Journal of Clinical Pediatrics》 2017年第1期81-88,共8页
AIM To increase evidence-based pain prevention strategy use during routine vaccinations in a pediatric primary care clinic using quality improvement methodology.METHODS Specific intervention strategies(i.e.,comfort po... AIM To increase evidence-based pain prevention strategy use during routine vaccinations in a pediatric primary care clinic using quality improvement methodology.METHODS Specific intervention strategies(i.e.,comfort positioning,nonnutritive sucking and sucrose analgesia,distraction) were identified,selected and introduced in three waves,using a Plan-Do-Study-Act framework.System-wide change was measured from baseline to post-intervention by:(1) percent of vaccination visits during which an evidence-based pain prevention strategy was reported as being used; and(2) caregiver satisfaction ratings following the visit.Additionally,self-reported staff and caregiver attitudes and beliefs about pain prevention were measured at baseline and 1-year post-intervention to assess for possible long-term cultural shifts.RESULTS Significant improvements were noted post-intervention.Use of at least one pain prevention strategy was documented at 99% of patient visits and 94% of caregivers were satisfied or very satisfied with the pain prevention care received.Parents/caregivers reported greater satisfaction with the specific pain prevention strategy used [t(143) = 2.50,P ≤ 0.05],as well as greater agreement that the pain prevention strategies used helped their children's pain [t(180) = 2.17,P ≤ 0.05] and that they would be willing to use the same strategy again in the future [t(179) = 3.26,P ≤ 0.001] as compared to baseline.Staff and caregivers also demonstrated a shift in attitudes from baseline to 1-year post-intervention.Specifically,staff reported greater agreement that the pain felt from vaccinations can result in harmful effects [2.47 vs 3.10; t(70) =-2.11,P ≤ 0.05],less agreement that pain from vaccinations is "just part of the process" [3.94 vs 3.23; t(70) = 2.61,P ≤ 0.05],and less agreement that parents expect their children to experience pain during vaccinations [4.81 vs 4.38; t(69) = 2.24,P ≤ 0.05].Parents/caregivers reported more favorable attitudes about pain prevention strategies for vaccinations across a variety of areas,including safety,cost,time,and effectiveness,as well as less concern about the pain their children experience with vaccination [4.08 vs 3.26; t(557) = 6.38,P ≤ 0.001],less need for additional pain prevention strategies [3.33 vs 2.81; t(476) = 4.51,P ≤ 0.001],and greater agreement that their doctors' office currently offers pain prevention for vaccinations [3.40 vs 3.75; t(433) =-2.39,P ≤ 0.05].CONCLUSION Quality improvement methodology can be used to help close the gap in implementing pain prevention strategies during routine vaccination procedures for children. 展开更多
关键词 PEDIATRICS quality improvement DISTRACTION PAIN management IMMUNIZATION VACCINATION Sucrose analgesia PAIN prevention Non-nutritive SUCKing Comfort positioning Primary care
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Does Positive Airway Pressure Therapy Result in Improved Sleep Quality?
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作者 Carl Stepnowsky Tania Zamora Christine Edwards 《Health》 2014年第18期2416-2424,共9页
Introduction: Positive airway pressure (PAP) therapy is the gold-standard for obstructive sleep apnea (OSA) management. While it is known that PAP is efficacious for controlling breathing events during sleep when it i... Introduction: Positive airway pressure (PAP) therapy is the gold-standard for obstructive sleep apnea (OSA) management. While it is known that PAP is efficacious for controlling breathing events during sleep when it is worn at the right pressure for the amount of time prescribed, there is less clear data on how well it improves sleep quality. There are few studies that have examined the effectiveness of PAP therapy on sleep quality. Methods: OSA participants (n = 241) from a larger trial examining a PAP adherence were included. Participants were provided with PAP instruction and followed at 2 months and 4 months. PAP adherence was measured as the number of hours per night at prescribed pressure, an objective measure of treatment adherence. The Pittsburgh Sleep Quality Index (PSQI) was used as the primary measure of sleep quality. Results: The PSQI was significantly correlated with PAP adherence at both the 2-month and 4-month time points, such that lower sleep quality was associated with lower PAP use. This finding held for the sleep disturbance subscale of the PSQI. Over 55% of those using PAP therapy at the 4-month time point continued to report significantly disturbed sleep. Discussion: This study shows that PAP therapy does not appear to improve sleep quality to a degree that would be expected. Over half of those patients using PAP therapy still experienced disturbed sleep. Whether the disturbed sleep is directly attributable to the PAP device itself or to disturbed sleep secondary to uncontrolled OSA when PAP is not worn is worthy of further investigation. 展开更多
关键词 Measurement Continuous positive AIRWAY Pressure SLEEP APNEA SYNDROMES SLEEP quality Treatment ADHERENCE
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Cultivation of Positive Psychological Quality for Primary School Students: Connotation and Approaches
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《南京晓庄学院学报》 2014年第2期123-124,共2页
关键词 positive PSYCHOLOGICAL quality primary SCHOOL STUDENTS
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To Vitalize the Northeast and Win by Quality Address at the Forum on the Strategy for Implement ing the Vitalization of the Northeast Old Industry Base Held by AQSIQ(selection)
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作者 Li Changjiang 《China Standardization》 2005年第5期28-34,共7页
The forum on the strategy for implementing the vitalization of the northeastold industry base was held on June 13^(th), 2005 in Shengyang by the General Adminitration ofQuality supervision, Inspection and Quarantine o... The forum on the strategy for implementing the vitalization of the northeastold industry base was held on June 13^(th), 2005 in Shengyang by the General Adminitration ofQuality supervision, Inspection and Quarantine of P.R. China (AQSIQ). The leaders in charge of theState Council Office of Northeast Vitalization and the Provincial Office of Vitalization ofLiaoning, Jilin and Heilongjiang were invited to attend the forum. At the forum, Director of AQSIQLi Changjiang made active response to the issues surrounding 'how the central government policy ofvitalizing Northeast can be fulfilled' and 'how the departments of quality inspection can fulfilltheir duty and play an active role'. 展开更多
关键词 In SELECTION To Vitalize the Northeast and Win by quality Address at the Forum on the Strategy for Implement ing the Vitalization of the Northeast Old Industry Base Held by AQSIQ
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MOCVD生长InGaAs/InGaAsP多量子阱光泵微碟激光器 被引量:2
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作者 吴根柱 张子莹 +1 位作者 任大翠 张兴德 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第8期1057-1062,共6页
用 MOCVD方法生长了 In Ga As/ In Ga As P多量子阱微碟激光器外延片 ,用光刻、干法刻蚀和湿法刻蚀等现代化的微加工技术制备出直径 9.5μm的 In Ga As/ In Ga As P微碟激光器 ,并详细介绍了整个制备工艺过程 .在液氮温度下用氩离子激... 用 MOCVD方法生长了 In Ga As/ In Ga As P多量子阱微碟激光器外延片 ,用光刻、干法刻蚀和湿法刻蚀等现代化的微加工技术制备出直径 9.5μm的 In Ga As/ In Ga As P微碟激光器 ,并详细介绍了整个制备工艺过程 .在液氮温度下用氩离子激光器泵浦方式实现了低阈值光泵激射 ,测出单个微碟激光器的阈值光功率为 15 0μW,激射波长约为 1.6μm,品质因数 Q=80 0 ,激射光谱线宽为 2 nm,同时指出微碟激光器激射线宽比 F- 展开更多
关键词 微碟激光器 多量子阱光泵 MOCVD生长 ingAAS/ingAASP
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Effects of plant density on cotton yield components and quality 被引量:5
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作者 ZHI Xiao-yu HAN Ying-chun +5 位作者 LI Ya-bing WANG Guo-ping DU Wen-li LI Xiao-xin MAO Shu-chun FENG Lu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第7期1469-1479,共11页
Yield and ifber quality of cotton even varies within locules in a bol, but it is not clear how yield components and quality parameters are altered across seed positions of a locule (SPL). A ifeld experiment was arra... Yield and ifber quality of cotton even varies within locules in a bol, but it is not clear how yield components and quality parameters are altered across seed positions of a locule (SPL). A ifeld experiment was arranged in a split plot design with transgenic insect resistant Bt (Bacilus thuringiensis) cotton hybrid cultivar CRI75 and conventional cultivar SCRC28 as the main plots, and three plant densities (15000, 51000 and 87000 plants ha–1) as the subplots in 2012 and 2013 at Anyang, Henan Province, China. Cotton was hand harvested by node and fruiting position, and then seeds of the ifrst fruiting posi-tion bols from nodes 6–10 were separated by SPL. The effects of plant density on lint yield, ifber quality, especialy across SPL were determined. It was showed that plant densities of 51000 and 87000 plants ha–1 increased lint yield by 61.3 and 65.3% in 2012 and 17.8 and 15.5% in 2013 relative to low plant density (15000 plants ha–1), however, no signiifcant differ-ence was observed between 51000 and 87000 plants ha–1. The number of bols (bol density) increased while bol weight decreased as plant density raised, and no signiifcant changes occured in lint percentage in 2013 but increased with plant density in 2012. The number of bols in upper nodes and distal fruiting positions, the number of seeds per bol, seed area (SA) and seed vigor index increased with decreasing plant density. Seed area was found to be greater from the base to the middle compared to the apex of a locule. Mote frequency (MF) increased as plant density increased, and ifber quality was the best at the middle of the locule regardless of plant density. As the number of ifbers per seed area is geneticaly determined, adjusting plant density to produce more seeds and greater seed area can be a potentialy promising alternative to improve lint yield in cotton. These ifndings might be of great importantance to cotton breeding and ifled management. 展开更多
关键词 COTTON plant density YIELD quality seed position
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UAV target tracking algorithm based on task allocation consensus 被引量:3
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作者 Yani Cui Jia Ren +1 位作者 Wencai Du Jingguo Dai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第6期1207-1218,共12页
In order to adapt to the changes in the states of moving targets and meet the requirements of quality of service in communication among unmanned aerial vehicles (UAVs), the UAVs formation needs to dynamically adjust t... In order to adapt to the changes in the states of moving targets and meet the requirements of quality of service in communication among unmanned aerial vehicles (UAVs), the UAVs formation needs to dynamically adjust tracking tasks and tracking paths, when they carry out a mission of tracking multiple moving targets. A multi-targets tracking algorithm based on task allocation consensus is proposed for UAVs to track multiple moving targets under the distributed control architecture in the limited communication range. This algorithm creates a distributed dynamic task allocation model using intermittent asynchronous communication principle to realize the sharing of observation information gathered by each UAV with fewer communications. In addition, this algorithm also makes it possible that multi-UAVs can plan tracking paths for multiple moving targets. We implement the algorithm on the formation with three UAVs to track three moving targets through simulation. Simulation results show the effectiveness of the proposed algorithm. © 2016 Beijing Institute of Aerospace Information. 展开更多
关键词 Closed loop control systems Motion planning quality of service Tracking (position) Unmanned aerial vehicles (UAV) Vehicle to vehicle communications
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ASYMPTOTIC SURROGATE CONSTRAINT METHOD AND ITS CONVERGENCE FOR A CLASS OF SEMI-INFINITE PROGRAMMING 被引量:2
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作者 Wan Zhongping\ Wu Guoming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1999年第4期485-491,共7页
A class of constrained semi\|infinite minimax problem is transformed into a simple constrained problem, by means of discretization decomposition and maximum entropy method, making use of surrogate constraint. The pa... A class of constrained semi\|infinite minimax problem is transformed into a simple constrained problem, by means of discretization decomposition and maximum entropy method, making use of surrogate constraint. The paper deals with the convergence of this asymptotic approach method. 展开更多
关键词 Sem i-infinite m inim ax program m ing discretization decom position m ethod m axim um en-tropy m ethod surrogate constraint CONVERGENCE
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Quality monitoring of real-time GNSS precise positioning service system 被引量:1
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作者 Run Ji Xinyuan Jiang +3 位作者 Xinghan Chen Huizhong Zhu Maorong Ge Frank Neitzel 《Geo-Spatial Information Science》 SCIE EI CSCD 2023年第1期1-15,共15页
The Real-Time Global Navigation Satellite System(GNSS)Precise Positioning Service(RTPPS)is recognized as the most promising system by providing precise satellite orbit and clock correc-tions for users to achieve centi... The Real-Time Global Navigation Satellite System(GNSS)Precise Positioning Service(RTPPS)is recognized as the most promising system by providing precise satellite orbit and clock correc-tions for users to achieve centimeter-level positioning with a stand-alone receiver in real-time.Although the products are available with high accuracy almost all the time,they may occasionally suffer from unexpected significant biases,which consequently degrades the positioning perfor-mance.Therefore,quality monitoring at the system-level has become more and more crucial for providing a reliable GNSS service.In this paper,we propose a method for the monitoring of realtime satellite orbit and clock products using a monitoring station network based on the Quality Control(QC)theory.The satellites with possible biases are first detected based on the outliers identified by Precise Point Positioning(PPP)in the monitoring station network.Then,the corresponding orbit and clock parameters with temporal constraints are introduced and esti-mated through the sequential Least Square(LS)estimator and the corresponding Instantaneous User Range Errors(IUREs)can be determined.A quality indicator is calculated based on the IUREs in the monitoring network and compared with a pre-defined threshold.The quality monitoring method is experimentally evaluated by monitoring the real-time orbit and clock products generated by GeoForschungsZentrum(GFZ),Potsdam.The results confirm that the problematic satellites can be detected accurately and effectively with missed detection rate 4×10^(-6) and false alarm rate 1:2×10^(-5).Considering the quality alarms,the PPP results in terms of RMS of positioning differences with respect to the International GNSS Service(IGS)weekly solution in the north,east and up directions can be improved by 12%,10%and 27%,respectively. 展开更多
关键词 Global Navigation Satellite System(GNSS) real-time precise positioning quality monitoring precise point positioning satellite product bias
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Pose Planning for the End-effector of Robot in the Welding of Intersecting Pipes 被引量:9
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作者 LIU Yu ZHAO Jing LU Zhenyang CHEN Shujun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第2期264-270,共7页
All-position robots are widely applied in the welding of complicated parts.Welding of intersecting pipes is one of the most typical tasks.The welding seam is a complicated saddle-like space curve,which puts a great ch... All-position robots are widely applied in the welding of complicated parts.Welding of intersecting pipes is one of the most typical tasks.The welding seam is a complicated saddle-like space curve,which puts a great challenge to the pose planning of end-effector.The special robots designed specifically for this kind of tasks are rare in China and lack sufficient theoretical research.In this paper,a systematic research on the pose planning for the end-effectors of robot in the welding of intersecting pipes is conducted. First,the intersecting curve of pipes is mathematically analyzed.The mathematical model of the most general intersecting curve of pipes is derived,and several special forms of this model in degraded situations are also discussed.A new pose planning approach of bisecting angle in main normal plane(BAMNP) for the welding-gun is proposed by using differential geometry and the comparison with the traditional bisecting angle in axial rotation plane(BAARP) method is also analytically conducted.The optimal pose of the welding-gun is to make the orientation posed at the center of the small space formed by the two cylinders and the intersecting curve to help the welding-pool run smoothly.The BAMNP method can make sure the pose vertical to the curve and center between the two cylinders at the same time,therefore its performance in welding-technique is superior to the BAARP method.By using the traditional BAARP method,the robot structure can become simpler and easier to be controlled,because one degree of freedom(DOF) of the robot can be reduced.For the special case of perpendicular intersecting,an index is constructed to evaluate the quality of welding technique in the process of welding.The effect of different combination of pipe size on this index is also discussed.On the basis of practical consideration,selection principle for BAARP and BAMNP is described.The simulations of those two methods for a serial joint-type robot are made in MATLAB,and the simulation results are consistent to the analysis.The mathematical model and the proposed new pose-planning method will lay a solid foundation for future researches on the control and design of all-position welding robots. 展开更多
关键词 pose planning ROBOT all-position welding intersecting pipes bisecting angle welding quality
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AMTS:Adaptive Multi-Objective Task Scheduling Strategy in Cloud Computing
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作者 HE Hua XU Guangquan +1 位作者 PANG Shanchen ZHAO Zenghua 《China Communications》 SCIE CSCD 2016年第4期162-171,共10页
Task scheduling in cloud computing environments is a multi-objective optimization problem, which is NP hard. It is also a challenging problem to find an appropriate trade-off among resource utilization, energy consump... Task scheduling in cloud computing environments is a multi-objective optimization problem, which is NP hard. It is also a challenging problem to find an appropriate trade-off among resource utilization, energy consumption and Quality of Service(QoS) requirements under the changing environment and diverse tasks. Considering both processing time and transmission time, a PSO-based Adaptive Multi-objective Task Scheduling(AMTS) Strategy is proposed in this paper. First, the task scheduling problem is formulated. Then, a task scheduling policy is advanced to get the optimal resource utilization, task completion time, average cost and average energy consumption. In order to maintain the particle diversity, the adaptive acceleration coefficient is adopted. Experimental results show that the improved PSO algorithm can obtain quasi-optimal solutions for the cloud task scheduling problem. 展开更多
关键词 quality of service cloud computing multi-objective task scheduling particle swarm optimization(PSO) small position value(SPV)
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Study on the Diagnostic Value of Combined Detection of Sperm Quality, Sex Hormone and Ovulation in Infertility
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作者 Jianhong Nong Dinggan Mo +2 位作者 Yisi Ou Jing Wen Mengying Lu 《Natural Science》 CAS 2022年第12期532-537,共6页
Objective: To analyze the application value of combined detection of sperm quality, sex hormone and ovulation in the diagnosis of infertility. Methods: The study was conducted from June 2021 to June 2022. Sixty infert... Objective: To analyze the application value of combined detection of sperm quality, sex hormone and ovulation in the diagnosis of infertility. Methods: The study was conducted from June 2021 to June 2022. Sixty infertile couples who received IVF cycle treatment in our hospital during this period were selected as the observation group, and 60 couples with good sperm quality and follicle number ≥ 5 who conceived naturally after gynecological disease treatment were selected as the control group during the same period. The sperm quality, sex hormones and ovulation of the two groups were observed, and the change of positive rate was detected by the combined detection method. Results: Compared with the control group, the observation group had less semen (2.82 ± 0.12) ml, lower concentration (69.17 ± 1.28) × 106/ml, normal sperm morphology rate (2.92% ± 0.11%), lower survival rate (70.25% ± 1.16%), higher deformed sperm index (1.39 ± 0.11), and significant differences between groups (P < 0.05);The levels of FSH (7.15 ± 1.33) U/L, LH (5.13 ± 0.53) mU/ml, E2 (72.34 ± 5.11) ng/L, AMH (3.87 ± 0.67) ng/ml and AFC (7.15 ± 0.76) in the control group were significantly better than those in the observation group (P < 0.05). Compared with the single detection method of the three groups, the positive detection rate of the combined diagnosis method was higher, and the difference between the groups was significant (P < 0.05). Conclusion: For the diagnosis of infertility, the combined detection method of sperm quality, sex hormone and ovulation can effectively clarify the problems existing in the couple, significantly improve the detection rate of the cause of the patient, and is more conducive to guiding clinical symptomatic treatment, which is worthy of promotion and reference. 展开更多
关键词 INFERTILITY Sperm quality Sex Hormones OVULATION Combined Test positive Rate
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