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成人乙型肝炎患者不同转归状态的生命质量效用权重评估 被引量:3
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作者 余倩 范小玲 +1 位作者 张曦 金承刚 《中国卫生经济》 北大核心 2016年第6期68-70,共3页
目的:测量乙型肝炎不同疾病状态下患者的生命质量效用权重。方法:随机选取北京市地坛医院4种疾病状态下的乙肝患者各60例,采用EQ5D问卷对患者进行问卷调查,并收集患者的性别和年龄。基于日本的人群偏好积分体系,利用多元广义线性模型评... 目的:测量乙型肝炎不同疾病状态下患者的生命质量效用权重。方法:随机选取北京市地坛医院4种疾病状态下的乙肝患者各60例,采用EQ5D问卷对患者进行问卷调查,并收集患者的性别和年龄。基于日本的人群偏好积分体系,利用多元广义线性模型评估各状态下患者的生命质量效用权重。结果:在校正了年龄和性别因素后,乙肝4个状态下患者的生命质量效用权重值为:慢性乙肝患者的生命质量效用权重值为0.818±0.038,代偿期肝硬化患者的生命质量效用权重值为0.802±0.033,失代偿期肝硬化患者的生命质量效用权重值为0.632±0.053,肝细胞癌患者的生命质量效用权重值为0.406±0.066。结论:患者患病程度越严重,患者的生命质量越差,生命质量效用权重越低。 展开更多
关键词 乙型肝炎 EQ5D 生命质量效用权重 广义线性模型
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多用户MIMO-OFDM系统基于QoE效用函数的跨层资源分配 被引量:7
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作者 王大鸣 陈松 +1 位作者 崔维嘉 王强 《通信学报》 EI CSCD 北大核心 2014年第9期175-183,共9页
对多用户MIMO-OFDM系统下行链路的资源分配问题进行了研究。依据实时(RT,real-time)和非实时(NRT,non real-time)业务的不同特点分别设计了QoE效用函数,并提出一种基于RT&NRT QoE效用函数的跨层资源分配算法。该算法利用所设计的效... 对多用户MIMO-OFDM系统下行链路的资源分配问题进行了研究。依据实时(RT,real-time)和非实时(NRT,non real-time)业务的不同特点分别设计了QoE效用函数,并提出一种基于RT&NRT QoE效用函数的跨层资源分配算法。该算法利用所设计的效用函数计算用户分得资源所贡献的QoE增量,并根据由QoE增量确定的用户优先级完成时频资源块的分配,进而通过"拟注水"方式对功率分配进行优化。仿真结果表明,该算法相比已有算法在用户平均QoE、实时业务平均分组时延、非实时业务平均分组丢失率以及系统和吞吐量方面的性能均得到了明显改善。 展开更多
关键词 多用户 多入多出正交频分复用 资源分配 跨层 用户感受质量效用函数
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配置效率视角下的数据质量水平分析
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作者 姜昊 梁林 张轶 《科技管理研究》 CSSCI 北大核心 2013年第15期251-255,265,共6页
目前信息系统已经被广泛应用到各种组织和产业当中,数据的获取来源和运行方式愈来愈多样化,由此产生的决策失误和经济损失造成的影响日益加剧,数据质量的高低已经成为日益突出的问题。然而单纯追求数据质量效用的最大化,也必然会增大管... 目前信息系统已经被广泛应用到各种组织和产业当中,数据的获取来源和运行方式愈来愈多样化,由此产生的决策失误和经济损失造成的影响日益加剧,数据质量的高低已经成为日益突出的问题。然而单纯追求数据质量效用的最大化,也必然会增大管理成本。从数据供应商和最终用户长期利益最大化的角度,构建数据质量管理成本和效用配置效率模型,并以轻型汽车产业为应用案例,利用模型分析其数据质量水平。 展开更多
关键词 数据质量管理 质量效用 管理成本 配置效率
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Effects of Potassium Fertilizing Rates on Yield, Fiber Quality and Potassium Use Efficiency of Three Hybrid Cotton Cultivars 被引量:1
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作者 冯正锐 刘爱玉 +3 位作者 易九红 李瑞莲 王欣悦 邹茜 《Agricultural Science & Technology》 CAS 2014年第2期200-204,共5页
The effects of potassium (K) application rates on the yield, fiber quality and K fertilizer use efficiency of three hybrid cotton varieties (Jin102, Xiangzamian8, Siyang328) were studied in field experiment. Ferti... The effects of potassium (K) application rates on the yield, fiber quality and K fertilizer use efficiency of three hybrid cotton varieties (Jin102, Xiangzamian8, Siyang328) were studied in field experiment. Fertilizer rates of K2O 135 and 270 kg/hm2, representing 1x and 2x recommended K rates, were applied, no application of k fertilizer as the CK. The results show that the lint yield increased 39.13%-57.48%with potassium application, highly significantly. Al yield components of the three hy-brid cotton varieties increased with the increase of K application amounts. The bol number per plant, single bol weight and lint percentage were increased by 14.24%-40.29%, 3.59%-15.51% and 0.16%-4.89%, respectively, and the fiber length and specific strength also increased with the increasing K application amounts, showing no significant influence on Micronaire. When the K application amounts increased from 135 to 270 kg/hm2, the partial factor productivity (PFPk) reduced by 45.93%-48.01%, and the agronomic efficiency (AEk) reduced by 37.1%-42.9%. The PFPk and KE (K efficiency coefficients) of S328 were the highest among the three varieties, which also showed the strongest resistance to low potassium stress, and with no potassi-um fertilizer application (K0), the lint yield of S328 was 5.54% and 11.19% higher than that of X8 and J102. The AEk of J102 was the highest, and its reward of K fertilizer was the greatest among the three varieties. 展开更多
关键词 Hybrid cotton Amount of Potassium Fertilizer Application YIELD Quality K use efficiency
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市场主体经济运行最佳方案选择的数学依据
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作者 张干英 何雁军 《新疆石油学院学报》 2000年第4期75-80,共6页
本文从管理学的基本原理出发 ,论述了在市场经济中 ,市场主体采用国际标准ISO90 0 0族《质量管理与质量保证体系》作为自己的管理模式 ,从而在对内对外贸易中获得最佳社会效益和经济效益 ,同时 ,对其管理模式抽象化、数学化 ,并证明了... 本文从管理学的基本原理出发 ,论述了在市场经济中 ,市场主体采用国际标准ISO90 0 0族《质量管理与质量保证体系》作为自己的管理模式 ,从而在对内对外贸易中获得最佳社会效益和经济效益 ,同时 ,对其管理模式抽象化、数学化 ,并证明了市场主体选择最优化的经济运行方案的存在性、有效性及其应用的现实性。 展开更多
关键词 ISO9000 质量效用 质量空间 质量度量 管理模式
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Power Control Algorithm of Cognitive Radio Based on Non-Cooperative Game Theory 被引量:4
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作者 赵军辉 杨涛 +2 位作者 贡毅 王娇 付雷 《China Communications》 SCIE CSCD 2013年第11期143-154,共12页
This paper addresses the power con- trol problems of Cognitive Radio (CR) trader transmission power and interference tempera- ture constraints. First, we propose the interfer- ence constraint which ensures that the ... This paper addresses the power con- trol problems of Cognitive Radio (CR) trader transmission power and interference tempera- ture constraints. First, we propose the interfer- ence constraint which ensures that the Quality of Service (QoS) standards for primary users is considered and a non-cooperative game power control model. Based on the proposed model, we developed a logical utility function based on the Signal-to-Interference-Noise Ratio (S/NR) and a novel algorithm network power control. that is suitable for CR Then, the existence and uniqueness of the Nash Equilibrium (NE) in our utility function are proved by the principle of game theory and the corresponding optimi- zations. Compared to traditional algorithms, the proposed one could converge to an NE in 3-5 iterative operations by setting an appropriate pricing factor. Finally, simulation results ver- ified the stability and superiority of the novel algorithm in flat-fading channel environments. 展开更多
关键词 cognitive radio non-cooperativepower control game theory utility function Na-sh equilibrium target power
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Three Critical Issues in Sustainable Development Studies and the Transition Development of China
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作者 Zhu Dajian 《Chinese Journal of Population,Resources and Environment》 2012年第2期24-30,共7页
The core issue for China transition development in the next 30 years is to shift from the quantity growth model to the quality improvement model. The paper introduces the research progress in three key areas of sustai... The core issue for China transition development in the next 30 years is to shift from the quantity growth model to the quality improvement model. The paper introduces the research progress in three key areas of sustainable development studies since the 1990s. It is pointed out that there is a well-being thresh-old at which the margin utility of economic growth for human well-being will decline, that there is an ecological limit beyond which more economic growth in terms of physical scale will be impossible, and that the creation of human well-being is related not only to the amount but also to the structure and efficiency of public expenditure from government. After an in-depth discussion on facts, origins and policy implications of each issue, some theory and policy thinking with long-lasting significance are raised for the transition development of China. 展开更多
关键词 transition development well-being threshold ecologi-cal limit public expenditure
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Performance of dual-source CT with high pitch spiral mode for coronary stent patency compared with invasive coronary angiography 被引量:10
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作者 Xia YANG Qiang YU +4 位作者 Wei DONG Zhen-Hong FU Jun-Jue YANG Jun GUO Yun-Dai CHEN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第10期817-823,共7页
Objective To investigate the performance of dual-source computed tomography (DSCT) using high-pitch spiral fliPS) mode for coronary stents patency. Methods We conducted a prospective study on 120 patients with 260 ... Objective To investigate the performance of dual-source computed tomography (DSCT) using high-pitch spiral fliPS) mode for coronary stents patency. Methods We conducted a prospective study on 120 patients with 260 previous stents implanted due to recurred suspicious symptoms of angina scheduled for invasive coronary angiography (ICA), while DSCT were conducted using HPS mode. Results There was no significant impact of age, body mass index or heat rate (HR) on image quality (P 〉 0.05), while HR variability had a slight impact on that (P 〈 0.05). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of DSCT in detection of in-stent restenosis (ISR) based per-patient were 92.3%, 96.7%, 88.9%, and 97.8%, respectively. And those based per-stent were 87%, 96.8%, 83.3%, and 97.7% with un-assessment stents, 97.4%, 99.5%, 97.4%, and 99.5% without un-assessment stents. There was significant differ- ence on sensitivity, specificity, PPV and NPV between diameter 〉 3.0 mm group (93.3%, 97.9%, 87.5%, and 98.9%) and diameter 〈 3.0 mm group (80%, 93.3%, 80.0%, and 93.3%) (P 〈 0.05), and that between stent number 〉 3 group (82.3%, 77.8%, 66.7%, and 60%) with 〈 3 group (97.3%, 80%, 96.5%, and 75%). The effective dose of DSCT (1.4 ± 0.5 mSv) is significantly less than that by invasive coronary angiography [4.0 ± 0.8 mSv (P 〈 0.01)]. Conclusion DSCT using HPS mode provides good diagnostic performance on stent patency with lower effective dose in patients with HR 〈 65 beats/rain. 展开更多
关键词 Coronary angiography High-pitch spiral mode Percutaneous coronary intervention STENT
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Power Consumption Optimization of Downlink Macro-Femto Heterogeneous Networks Based on Cross-Layer Design
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作者 张秀宁 谈振辉 +2 位作者 徐少毅 张金宝 陶成 《China Communications》 SCIE CSCD 2013年第2期42-55,共14页
Based on the cross-layer design, the power-optimization problem of Macro-Femto Heterogeneous Networks (HetNets) has been formulated. The constraints of power and re-source block allocation in the physical layer, del... Based on the cross-layer design, the power-optimization problem of Macro-Femto Heterogeneous Networks (HetNets) has been formulated. The constraints of power and re-source block allocation in the physical layer, delay and target data rate in the medium ac-cess control layer, urgent queue length in the network layer, and packet error rate in the transport layer, have been considered. The original problem is non-deterministic polyno-mial time hard, which cannot be solved practi-cally. After the restrictions of upper layers are translated into constraints with physical layer parameters, and the integer restrictions are relaxed, the original problem can be decom- posed into convex optimization subproblems. The optimal solutions of resource block allo-cation and power allocation can be obtained by using the Lagrangian optimization. Simula-tion results show that the proposed scheme is better than both the round robin algorithm and the max-rain one in terms of energy efficiency, throughput and service fairness. The round robin algorithm and the max-min one only focus on the user fairness rather than quality of service fairness. Compared to the round robin scheme (the max-min one), the proposed scheme improves the energy efficiency 58.85% (62.41%), the throughput 19.09% (25.25%), the service fairness 57.69% (35.48%). 展开更多
关键词 cross-layer design Macro-FemtoHetNets MIMO-OFDM energy efficiency
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高填方地基填筑相对密度影响因素及控制方法
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作者 谢伟 《市政设施管理》 2023年第2期15-18,共4页
针对大型山地水厂项目在高填方地基施工过程中存在的填筑相对密度不足的质量问题,进行关键因素分析、质量过程控制,提出解决问题的具体方法和关键技术方法,同时阐明工程质量控制课题步骤流程、实施要点,为该类工程的建设提供参考。
关键词 市政工程 高填方地基 质量控制效用流程
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Wireless Sensor Networks for Optimisation of District Heating
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作者 Anatolijs Zabasta Viesturs Selmanovs-Pless +1 位作者 Nadezda Kunicina Leonids Ribickis 《Journal of Energy and Power Engineering》 2013年第7期1362-1369,共8页
The upgrading of the DH (district heating) system through installing WSN (wireless sensor networks)--a technology by which to monitor and control quality operation of the DH system will lead to more effective use ... The upgrading of the DH (district heating) system through installing WSN (wireless sensor networks)--a technology by which to monitor and control quality operation of the DH system will lead to more effective use of thermal energy, enabling also the provision of quality customer services, as the data concerning the status of the existing networks is available in a timely manner, and in the stated amounts. Over the last decades, the use of WSN systems in enabling quality monitoring of heat production and supply process has been widely discussed among various researchers and industry experts, but has been little deployed in practice. These researchers and industry experts have analysed the advantages and constraints related to the use of the WSN in district heating. A pilot project conducted by Riga Heat (the main heating supplier in Riga, Latvia) has allowed to gain a real life experience as to the use of the WSN system in district in-house heating substations, and is deemed to be a major step towards future development of WSN technologies. 展开更多
关键词 District heating GPRS heating substation wireless sensor networks XML.
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考虑质量水平的产品更新策略研究 被引量:2
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作者 李乃梁 何伊 +2 位作者 李玉鹏 张畅 郭少英 《中国管理科学》 CSSCI CSCD 北大核心 2021年第11期78-87,共10页
将质量水平作为关键因子引入到更新产品设计的最优决策问题。通过界定质量水平、质量效用、顾客质量偏好及产品更新率的内涵,构建了新旧产品同时存于市场的竞争模型和旧产品退出市场的非竞争模型,求解得到了质量效用、质量水平改进量和... 将质量水平作为关键因子引入到更新产品设计的最优决策问题。通过界定质量水平、质量效用、顾客质量偏好及产品更新率的内涵,构建了新旧产品同时存于市场的竞争模型和旧产品退出市场的非竞争模型,求解得到了质量效用、质量水平改进量和顾客质量偏好的关系,确定了更新产品最佳质量水平的取值。通过数值分析,验证与分析了最佳质量水平与质量效用的关系,给出了新旧产品价格与质量优势区间,为企业的产品更新决策提供了科学依据。 展开更多
关键词 产品更新 质量水平 顾客质量偏好 质量效用
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Increasing Production Efficiency through Casting Quality Improving by Electromagnetic Field Applying
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作者 Marija Mihailovic Aleksandra Pataric Zvonko GuliSija Miroslav Sokic 《Journal of Mechanics Engineering and Automation》 2012年第1期59-62,共4页
The increased production efficiency of heat treatable A1 alloys, as the result of applied electromagnetic field during continuous casting process was investigated. The applied frequency of the electromagnetic field (... The increased production efficiency of heat treatable A1 alloys, as the result of applied electromagnetic field during continuous casting process was investigated. The applied frequency of the electromagnetic field (EMF) during the AI alloys continuous casting was changing from 30 Hz to 50 Hz, while some castings were obtained without the EMF influence. The mechanical characterization of continuous casted AI alloys EN AW 2007 and En AW 2024 was done on testing machine Zwick/Roell Z 100. The microstructure of as-cast samples was examined, as well. When the frequency decreases (from 50 Hz to 30 Hz), the grain size decreases as well, what is noticeable through the finer microstructure and its uniformity throughout the cross-section. These results have shown that low frequency electromagnetic field significantly influenced the microstructure and therefore the mechanical properties of as cast ingots. Thus, through improved castings quality, operation time and energy savings, the production efficiency was increased. 展开更多
关键词 AI alloys electromagnetic field CASTING production efficiency.
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Continued application of Endostar combined with chemotherapy in advanced hemangioendothelioma of bone
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作者 Ningrong Yang Lin Wang Xun Chen Shukui Qin 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第11期672-675,共4页
By one case of hemangioendothelioma of bone accompanying pulmonary metastasis was treated with rh-endostatin injection (Endostar) combined with chemotherapy. The patient got partial response (PR) for 3 years after the... By one case of hemangioendothelioma of bone accompanying pulmonary metastasis was treated with rh-endostatin injection (Endostar) combined with chemotherapy. The patient got partial response (PR) for 3 years after the application of Endostar maintenance therapy and Endostar combined with taxane-based chemotherapy. During the period of using Endostar as monotherapy, the patient got long-term disease control and good quality of life. There was no drug related adverse event during the therapy of Endostar. Suggested continued using of Endostar combined with chemotherapy could achieve an convinced therapeutic effect. Then using Endostar as maintenance treatment after patient got the optimal efficacy was feasible and profitable. This treatment strategy of long-term administration of Endostar was worthy of further observation, to explore the feasibility for long-term administration of combined with chemotherapy in the treatment of hemangioendothelioma of bone accompanying pulmonary metastasis. 展开更多
关键词 hemangioendothelioma of bone rh-endostar/Endostar ANTI-ANGIOGENESIS maintenance therapy
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质量调整生命年:挑战
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作者 宗欣 吴晶 《中国药物经济学》 2009年第6期74-83,共10页
一、简介 Weinstein等人阐述了QALY的概念、方法及暗含的假设。尽管引起了许多有趣的争论,但本文仅限于对我们认为最具挑战性的四个争论点进行研究。
关键词 质量调整多属性效用(MAU) 经验效用(experience utility) 减法(subtraction method) 公平性
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Development of a novel quality standard of Indigoplant
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作者 徐珊珊 李清 +2 位作者 王新丽 李璐 毕开顺 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第5期415-419,共5页
Traditional Chinese medicine (TCM) has been widely used in China for thousands of years, and has received more and more recognition worldwide. Indigoplant (Folium Polygoni Tinctorii), a TCM, has been used in vario... Traditional Chinese medicine (TCM) has been widely used in China for thousands of years, and has received more and more recognition worldwide. Indigoplant (Folium Polygoni Tinctorii), a TCM, has been used in various diseases. In our study, we established a quality standard of Indigoplant according to the European Pharmacopoeia, and this standard has passed the early audit stages of the European Pharmacopoeia Commission. The lndigoplant samples were identified with high performance thin layer chromatography (HPTLC), qualified with RP-HPLC quantitation, and analyzed with a series of quality tests. An accurate, reliable and robust HPLC method with gradient elution for quantitation was developed and validated with a one-variable-at-a-time (OVAT) robustness approach. Several tests, including the loss on drying, total ash and ash insoluble in hydrochloric acid of Indigoplant, were performed for quality analysis. Furthermore, six batches of the Indigoplant samples were appraised with this quality standard. In conclusion, the established quality standard was more internationally normative and applicable for the quality control of Indigoplant in practical application. 展开更多
关键词 Indigoplant European Pharmacopoeia Quality standard HPTLC ROBUSTNESS
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Relationships Between Yield, Quality and Nitrogen Uptake and Utilization of Organically Grown Rice Varieties 被引量:12
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作者 HUANG Lifen YU Jun +4 位作者 YANG Jie ZHANG Rong BAI Yanchao SUN Chengming ZHUANG Hengyang 《Pedosphere》 SCIE CAS CSCD 2016年第1期85-97,共13页
Due to the relatively late start of organic rice(Oryza sativa L.) research in China,there is a still lack of systematic research on rice varieties,organic fertilizer management practices,and especially the mechanisms ... Due to the relatively late start of organic rice(Oryza sativa L.) research in China,there is a still lack of systematic research on rice varieties,organic fertilizer management practices,and especially the mechanisms of nitrogen(N) uptake and utilization.Three rice varieties,Nanjing 5055,Nanjing 9108,and Nanjing 46,were grown under organic farming(OF) at three organic fertilizer levels(103.2,160.8,and 218.4 kg N ha^(-1)) and conventional farming(CF) with regular chemical fertilizers.Rice grain yields,yield components,and quality,dry matter accumulation,and plant N were measured at different growth stages during the 2012 and 2013 growing seasons.Compared with CF,OF had a significantly reduced yield.Nanjing 9108 showed significant reductions in number of panicles per unit area and percentage of filled grains,and had the lowest yield.The effects of fertilizer type and application rate on dry matter accumulation during the main growth periods were significant for all varieties.The N content and uptake in organically grown rice were lower compared with those of rice under CF.The N recovery efficiency and N agronomic efficiency were significantly lower,whereas N physiological efficiency and N partial factor productivity were greater under OF than under CF.Under OF,the processing quality showed a slight but insignificant decline,protein content and gel consistency increased,and amylose content decreased compared with those under CF.Correlation analysis showed that under OF,grain yield was significantly correlated with N uptake.The medium organic fertilizer level(160.8 kg N ha^(-1)) was found to be the optimum fertilizer treatment,and Nanjing 46 appeared to be the best variety for organic rice cultivation.To increase rice grain yields and reduce the potential risk of non-point source pollution in organic agriculture,further research is needed to improve the N use efficiency in organic rice cultivation. 展开更多
关键词 conventional farming grain quality grain yield N use efficiency organic farming organic fertilizer
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