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波动方程all-at-once系统的快速α循环绝对值预处理
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作者 徐果 张建华 《江西科学》 2024年第2期239-243,共5页
为了加快预处理MINRES方法求解波动方程all-at-once系统的收敛速度,基于绝对值预处理子和块状三对角Toeplitz预处理子,提出一种新的α循环绝对值预处理子。理论上证明了预处理矩阵可近似分裂成正交矩阵与低秩矩阵的和,且其特征值聚集在&... 为了加快预处理MINRES方法求解波动方程all-at-once系统的收敛速度,基于绝对值预处理子和块状三对角Toeplitz预处理子,提出一种新的α循环绝对值预处理子。理论上证明了预处理矩阵可近似分裂成正交矩阵与低秩矩阵的和,且其特征值聚集在±1附近,保证了预处理MINRES方法的快速收敛性质。数值实验结果进一步表明了新预处理子的有效性。 展开更多
关键词 波动方程 all-at-once系统 预处理MINRES α循环绝对值预处理子
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关于一些李型单群的ONC-刻画 被引量:2
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作者 何立官 《重庆师范大学学报(自然科学版)》 CAS CSCD 北大核心 2017年第5期49-53,共5页
【目的】为了弱化有限单群数量刻画的数量条件。【方法】用第一ONC-度量ONC_1(G)刻画了李型单群L_2(q)(q=11,13,16,19,23,25,29)。【结果】证明了L_2(q)(q=11,13,19,23,29)可以由ONC_1(G)唯一确定,并给出了在条件ONC_1(G)=ONC_1(L2(q))(... 【目的】为了弱化有限单群数量刻画的数量条件。【方法】用第一ONC-度量ONC_1(G)刻画了李型单群L_2(q)(q=11,13,16,19,23,25,29)。【结果】证明了L_2(q)(q=11,13,19,23,29)可以由ONC_1(G)唯一确定,并给出了在条件ONC_1(G)=ONC_1(L2(q))(q=16,25)下,G的分类。【结论】结果说明不是所有李型单群L_2(q)都可以ONC-刻画。 展开更多
关键词 李型单群 onc-度量 onc-刻画
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关于一些交错单群的ONC-刻画
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作者 何立官 童殷 《重庆师范大学学报(自然科学版)》 CAS CSCD 北大核心 2018年第3期90-95,共6页
【目的】为了弱化有限群数量刻画的数量条件。【方法】用第一ONC-度量ONC1(G)刻画了交错单群An(5≤n≤13)。【结果】证明了An(n=5,6,7,10,11,13)可以由ONC1(G)唯一确定,而A8,A9,A12可由ONC1(G)和lp(G)唯一确定。【结论】结果说明交错单... 【目的】为了弱化有限群数量刻画的数量条件。【方法】用第一ONC-度量ONC1(G)刻画了交错单群An(5≤n≤13)。【结果】证明了An(n=5,6,7,10,11,13)可以由ONC1(G)唯一确定,而A8,A9,A12可由ONC1(G)和lp(G)唯一确定。【结论】结果说明交错单群An(5≤n≤13)最多需要4个数量就可以唯一刻画。 展开更多
关键词 交错单群 onc-度量 onc-刻画
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Study on the Optimum Moisture Amount Added to Brown Rice once during the Wet Conditioning 被引量:8
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作者 BAI Shi-gang JIA Fu-guo NAN Jing-fu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第2期137-140,共4页
In the experiment, the brown rice whose moisture content was 12.5% was used as raw material. The brown rice was grouped, then moisturized differently and milled. While milling, the energy consumption, the rate of brok... In the experiment, the brown rice whose moisture content was 12.5% was used as raw material. The brown rice was grouped, then moisturized differently and milled. While milling, the energy consumption, the rate of broken rice and the crack rate were tested. It is confirmed that the stress crack owing to the moisture added to the brown rice can be avoided when the moisture amount added once is limited to no more than 1.5%. It is also proved that the energy consumption can be reduced, the yielding rate of rice can be increased and that the quality of rice can be improved. 展开更多
关键词 brown rice rice milling moisture conditioning the optimum moisture amount added once
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基于MMC2107 OnCE的Flash编程技术
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作者 俞芳 王宜怀 《电子器件》 EI CAS 2005年第4期902-905,共4页
阐述了如何通过Motorola32位MCUMMC2107的OnCE接口,实现对MMC2107的片外Flash存储器的编程。详细介绍了OnCE模块的实现原理、内部工作机制、硬件系统设计、软件编程方法及程序接口。并且提出了OnCE简易硬件接口的原理设计、编程模型、... 阐述了如何通过Motorola32位MCUMMC2107的OnCE接口,实现对MMC2107的片外Flash存储器的编程。详细介绍了OnCE模块的实现原理、内部工作机制、硬件系统设计、软件编程方法及程序接口。并且提出了OnCE简易硬件接口的原理设计、编程模型、软件接口划分、操作流程,以及提高Flash编程速度的改进方案,探讨其中一些关键技术和实现细节。 展开更多
关键词 M*CORE MMC2107 oncE FLASH
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Evaluation of the long-term safety and effectiveness of tadalafil once daily in Chinese men with erectile dysfunction: interim results of a multicenter, randomized, open-label trial 被引量:3
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作者 Hui Jiang Lian-Ming Zhao +8 位作者 Hao-Cheng Lin Su Yan Ji-Hong Liu Zhao-Hui Zhu Jin-Dan Luo Yu-Tian Dai Fu-Biao Li Ying Lou Zhi-Chao Zhang 《Asian Journal of Andrology》 SCIE CAS CSCD 2018年第6期587-592,共6页
Once-daily tadalafil administration has been well established; however, studies about tadalafil once-daily treatment in the Chinese population are lacking. In this phase 4, postmarketing study, we ascertained the long... Once-daily tadalafil administration has been well established; however, studies about tadalafil once-daily treatment in the Chinese population are lacking. In this phase 4, postmarketing study, we ascertained the long-term safety and effectiveness of tadalafil 2.5 mg and 5.0 mg once daily in Chinese men with erectile dysfunction (n = 635). The primary endpoint of the study was safety at 12 months as assessed by the proportion of patients experiencing at least one treatment-emergent adverse event (serious or nonserious). The secondary endpoints included safety and effectiveness, measured by the International Index of Erectile Function-Erectile Function (IIEF-EF) domain scores. Similar adverse events to the known safety profile of tadalafil, such as nasopharyngitis, upper respiratory tract infection, headache, and dizziness, were detected. No new cardiovascular safety concerns were observed. After 3 months of treatment, significant increases in IIEF-EF domain scores were detected for both 2.5-mg (least squares [LS] mean change: 6.3; 95% confidence interval [CI]: 5.4-7.1; P 〈 0.001) and 5.0-mg (LS mean change: 7.4; 95% CI: 6.8-7.9; P 〈 0.001) tadalafil doses, and significance was maintained up to 12 months. In addition, approximately 40% of patients regained normal erectile function (IIEF-EF 〉26) following 1 year of tadalafil once-daily treatment. The findings in this study provide evidence for the extended effectiveness and tolerability of tadalafil, demonstrating no new safety concerns, in a Chinese population and make once-daily tadalafil administration a viable option for improving sexual performance and satisfaction in Chinese men with erectile dysfunction. 展开更多
关键词 erectile dysfunction long-term safety once-daily dosing TADALAFIL
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基于You Only Look Once v2优化算法的车辆实时检测 被引量:4
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作者 王楷元 韩晓红 《济南大学学报(自然科学版)》 CAS 北大核心 2020年第5期443-449,共7页
针对基于You Only Look Once v2算法的目标检测存在精度低及稳健性差的问题,提出一种车辆目标实时检测的You Only Look Once v2优化算法;该算法以You Only Look Once v2算法为基础,通过增加网络深度,增强特征提取能力,同时,通过添加残... 针对基于You Only Look Once v2算法的目标检测存在精度低及稳健性差的问题,提出一种车辆目标实时检测的You Only Look Once v2优化算法;该算法以You Only Look Once v2算法为基础,通过增加网络深度,增强特征提取能力,同时,通过添加残差模块,解决网络深度增加带来的梯度消失或弥散问题;该方法将网络结构中低层特征与高层特征进行融合,提升对小目标车辆的检测精度。结果表明,通过在KITTI数据集上进行测试,优化后的算法在检测速度不变的情况下,提高了车辆目标检测精度,平均精度达到0.94,同时提升了小目标检测的准确性。 展开更多
关键词 深度学习 车辆检测 You Only Look once v2算法 残差模块 特征融合
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A dynamic model of once-daily 5-aminosalicylic acid predicts clinical efficacy 被引量:1
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作者 Deepak Parakkal Eli D Ehrenpreis +2 位作者 Matthew P Thorpe Karson S Putt Bruce Hannon 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第1期136-137,共2页
New once daily mesalamine formulations may improve adherence to medication usage.Response to Asacol and other forms of 5-aminosalicyclic acid(5-ASA)is better correlated with tissue concentrations and best predicted by... New once daily mesalamine formulations may improve adherence to medication usage.Response to Asacol and other forms of 5-aminosalicyclic acid(5-ASA)is better correlated with tissue concentrations and best predicted by concentrations of the drug within the lumen of the colon.Our group used computer simulation to predict colonic 5-ASA levels after Asacol administration.In our study,the model simulated Asacol distribution in the healthy colon,and during quiescent and active ulcerative colitis.An Asacol dosage of 800 mg,threetimes a day,was compared to 2400 mg given once a day.Under ideal conditions,the predicted maximum drug in the total colon and individual colonic segments over 100 d differed by less than 3%between single and multiple doses.Despite changes in motility and defection rates,the predicted maximum and average 5-ASA concentrations in the total colon and individual colonic segments differed by less than 10%between dosing regimens.Asymmetric distribution of 5-ASA in the colon was influenced by frequency of bowel movements and colonic transit rate.In active colitis,sigmoid 5-ASA concentration becomes negligible.Our model supports once daily administration of Asacol as standard treatment for ulcerative colitis. 展开更多
关键词 Ulcerative colitis 5-aminosalicylate MESALAZINE Asacol oncE-DAILY
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Comparison of the efficacy and safety of once-daily dosing and on-demand use of udenafil for type 2 diabetic patients with erectile dysfunction 被引量:2
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作者 Soon Hyun Park Sung Woo Park +6 位作者 Bong Yun Cha Ie Byung Park Kyung Wan Min Yeon Ah Sung Tae Hwa Kim Jae Min Lee Kang Seo Park 《Asian Journal of Andrology》 SCIE CAS CSCD 2015年第1期143-148,I0011,I0012,共8页
We compared the efficacy and safety between once-daily dosing and on-demand use of udenafil for type 2 diabetic patients with erectile dysfunction (ED). A multi-center, randomized, open-label, parallel-group, 12-wee... We compared the efficacy and safety between once-daily dosing and on-demand use of udenafil for type 2 diabetic patients with erectile dysfunction (ED). A multi-center, randomized, open-label, parallel-group, 12-week study was conducted. 161 patients who improved with on-demand 200 mg of udenafil according to Sexual Encounter Profile (SEP) diary Question 2 and 3 (Q2 and Q3) were randomized into 200 mg on-demand (n = 80) or 50 mg once-daily (n = 81) dosing groups for 8 weeks. The dosing period was followed by a 4-week treatment-free period. The primary efficacy endpoint was the change of the International Index of Erectile Function (IIEF) erectile function domain (EFD) score. The secondary efficacy endpoints included changes to the SEP diary Q2, Q3, IIEF Q3, Q4, other domains of IIEF, Global Assessment Question, and shift to the normal rate (EFD 〉 26). Vascular endothelial markers were also assessed. The IIEF-EFD score of both groups improved after 8 weeks of treatment (P 〈 0.0001). There was no statistically significant difference between two groups. Improvement was not maintained after the treatment-free follow-up period. Similar results were observed in the secondary efficacy endpoints. There was also no significant difference in vascular endothelial markers. Daily udenafil was well-tolerated, and there was no significant difference in the adverse drug reactions and adverse events between the two groups. Flushing and headache were the most frequent adverse events. Both regimens improved ED in diabetic patients and were well-tolerated. Further studies are needed to assess the effect of daily udenafil treatment in diabetic patients. 展开更多
关键词 erectile dysfunction International Index of Erectile Function once-daily dosing ptiosphodiesterase type 5 inhibitor type 2 diabetes mellitus UDENAFIL
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The Antifreeze Critical Strength of Low-temperature Concrete Effected by Index 被引量:2
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作者 刘军 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第2期355-360,共6页
The antifreeze critical strength and the pre-curing time of low-temperature concrete were studied by means of guaranteed rate of compressive strength and antifreeze performance for the structural safety requirement of... The antifreeze critical strength and the pre-curing time of low-temperature concrete were studied by means of guaranteed rate of compressive strength and antifreeze performance for the structural safety requirement of concrete engineering,suffering once freeze damage under air environment.It is shown that the antifreeze critical strength is 3.7-4.4MPa,pre-curing time is 18-32 h by guaranteed rate of compressive strength,and the antifreeze critical strength is 3.7-4.4MPa,pre-curing time is 18-32 h by guaranteed rate of antifreeze performance.It can be found that the method of guaranteed rate of compressive strength is sensitive to the defect which generated by freeze damage in the concrete interior.The method is fit to evaluate the antifreeze critical strength of low-temperature concrete. 展开更多
关键词 guaranteed rate of compressive strength guaranteed rate of antifreeze performance antifreeze critical strength once freeze under air environment
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A Three-layered Contrasting Analysis of the Theme in Once more to the lake
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作者 杨晶 《海外英语》 2017年第13期163-165,共3页
Once more to the lake is a representative work of the American Writer, Elwyn Brooks White, and has been acclaimed by people in the world. The paper offers a three-layered contrasting analysis of the essay. By detailed... Once more to the lake is a representative work of the American Writer, Elwyn Brooks White, and has been acclaimed by people in the world. The paper offers a three-layered contrasting analysis of the essay. By detailed analysis of the contrasts running through the whole essay, the author finds that those contrasts are symbol of White's internal struggle and reflection for life.On the foundation of the three-layered contrasts, the paper presents the theme analysis and clarifies the content of the essay. 展开更多
关键词 three-layered contrasting analysis White once more to the lake
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An Only-Once-Sorting Algorithm
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作者 Xu Xusong Zhou Jianqin Guo Feng (School of Management,Wuhan University, Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第1期38-41,共4页
This paper provides a new sorting algorithm called 'Only-Once-Sorting' algorithm a mathemati cal formula,this algorithm can put elements in the positions they should be stored only once,then compacts them.The ... This paper provides a new sorting algorithm called 'Only-Once-Sorting' algorithm a mathemati cal formula,this algorithm can put elements in the positions they should be stored only once,then compacts them.The algorithm completes sorting a sequence of n elements in a calculation time of O(n ). 展开更多
关键词 mathematical formula onlv-once-sorting sorting algorithm
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ONC206抑制浆液性乳头状子宫内膜癌增殖和转移的体外研究
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作者 黄裕 王冬 +2 位作者 顾荣花 邹冬玲 周琦 《肿瘤学杂志》 CAS 2020年第9期796-802,共7页
[目的]探讨ONC206对子宫浆液性乳头状腺癌(UPSC)细胞系增殖、粘附和侵袭的作用,评估其抗肿瘤效能,并分析其机制。[方法]用ONC201或ONC206治疗UPSC细胞系ARK1和SPEC2,MTT法和半胱天冬酶-3、9(Caspase-3,9)测定检测细胞增殖和凋亡,并进行... [目的]探讨ONC206对子宫浆液性乳头状腺癌(UPSC)细胞系增殖、粘附和侵袭的作用,评估其抗肿瘤效能,并分析其机制。[方法]用ONC201或ONC206治疗UPSC细胞系ARK1和SPEC2,MTT法和半胱天冬酶-3、9(Caspase-3,9)测定检测细胞增殖和凋亡,并进行粘附实验、伤口愈合实验量化其降低转移和侵袭的能力,进行活性氧(ROS)和JC-1检测,分析整合应激反应(ISR)。使用整合应激抑制剂N-乙酰半胱氨酸预处理后,重复进行ONC206的增殖,侵袭和应激测定,蛋白质印迹法检测相应蛋白表达水平。[结果]在UPSC细胞系ARK1和SPEC2中,ONC206以浓度依赖方式抑制其增殖,平均IC50值分别为330nM和240n M,均低于ONC201。Caspase-3、9表达水平升高,ROS与基线相比增加83%~105%,线粒体膜电位降低16%~38%,ISR特异性蛋白表达增加,上皮-间质转化蛋白表达下调。使用NAC后,ONC206对肿瘤细胞黏附、增殖和侵袭的抑制功效降低。[结论]亚吡哌酮家族药物ONC206通过肿瘤坏死因子相关凋亡诱导配体(TRAIL)介导的凋亡途径,同时激活ISR传播下游效应,降低UPSC肿瘤细胞的增殖、粘附和侵袭能力。 展开更多
关键词 onc206 子宫内膜癌 侵袭转移 凋亡 整合应激反应
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Stage Predictions of Landslide and Subsidence from an Once-Through Cycle
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作者 Yan TongzhenDepartment of Hydrogeology and Engineering Geology, China University of Geosciences, Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1990年第1期77-86,共10页
In this paper both processes of landslide and subsidence are considered to be limited systems. Each of these systems in nature might be regarded as an organism. Generally their lifespan must develop with common ecolog... In this paper both processes of landslide and subsidence are considered to be limited systems. Each of these systems in nature might be regarded as an organism. Generally their lifespan must develop with common ecological characteristics, including several evolutional stages, such as initiation, growth, maturation, decline and death. Among these stages, maturation is emphasized so as to find the occurring or thriving date of both systems. An once-through cycle of both landslide and subsidence is established and is accurately predicted by a developed, mathematic model of the Poisson cycle. The Weibull distribution is cited for a landslide example. Both fundamentals are discussed. Stage predictions of landslide and subsidence are performed for several examples. Back analysis of landslides that have already happened are studied with the same model. And when compared with results from the biological mathematic model and with practical results, it is found that they correspond. Stage prediction of subsidences is also researched by the principle of the Poisson cycle. 展开更多
关键词 limited system LANDSLIDE SUBSIDENCE stage predictions of an once-through cycle the Poisson cycle the Weibull distribution back analysis/future analysis.
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Safety and Efficacy of Once-Daily Administration of Mycophenolate Mofetil in Kidney Transplant Patients—A New Treatment Option for Non-Adherence
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作者 Naotsugu Ichimaru Kazuaki Yamanaka +6 位作者 Taigo Kato Yoichi Kakuta Toyofumi Abe Jun-ya Kaimori Ryoichi Imamura Norio Nonomura Shiro Takahara 《Journal of Biomedical Science and Engineering》 2014年第10期788-791,共4页
Non-adherence to immunosuppressive therapy is associated with reduced graft survival. Fifteen long-term follow up kidney transplant patients with stable post-transplant clinical courses were enrolled in the study. All... Non-adherence to immunosuppressive therapy is associated with reduced graft survival. Fifteen long-term follow up kidney transplant patients with stable post-transplant clinical courses were enrolled in the study. All patients were prescribed to tacrolimus prolonged release, mycophenolate mofetil (MMF) and corticosteroid at the time of enrolment. Twice-daily administration of MMF was then converted to a single daily dose. As a result, all immunosuppressive agents were administered simultaneously at one time in the morning. The daily total doses of the three immunosuppressants were identical during the study period. No acute rejection or adverse event was observed during the study period. Blood urea nitrogen and estimated glomerular filtration rate did not change significantly after conversion to once-daily administration. The blood tacrolimus trough level and the Mycophenolic acid (MPA) trough level also did not change significantly after conversion to once-daily administration. Interestingly, the meanmedian MPA trough level remained >3 μg/ml even after conversion to once-daily administration. A sufficient plasma MPA level was maintained after conversion to once-daily administration, and no acute rejection was observed during the study period. To our knowledge, this study is the first to report that the plasma MPA concentration can be maintained after once-daily administration of MMF in long-term kidney transplant patients. Once-daily administration of immunosuppressive agents may improve long-term graft survival because of better treatment adherence due to the reduced dosing frequency. The safety or efficacy of conversion to once-daily administration of MMF should be evaluated in a future randomized controlled large-scale clinical study. 展开更多
关键词 oncE-DAILY ADMINISTRATION MYCOPHENOLATE Mofetil TREATMENT ADHERENCE
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Osteonecrosis of the jaw in a patient taking once-yearly infusion of zoledronic acid for osteopenia
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作者 Takako Imai Tanaka Charles Donald Taylor 《Case Reports in Clinical Medicine》 2013年第9期535-537,共3页
Osteonecrosis of the jaw (ONJ) is an adverse effect of nitrogen-containing bisphosphonates. Advancing age, intravenous administration of zoledronic acid (ZOL), history of dento-alveolar surgery, and concomitant system... Osteonecrosis of the jaw (ONJ) is an adverse effect of nitrogen-containing bisphosphonates. Advancing age, intravenous administration of zoledronic acid (ZOL), history of dento-alveolar surgery, and concomitant systemic diseases such as diabetes are known as risk factors for developing ONJ. However, despite numerous studies, the exact pathophysiology remains unclear and management strategies are largely anecdotal. Once-yearly intravenously administered 5 mg ZOL was approved by the US Food and Drug Administration in 2007 for the treatment of osteoporosis and its efficacy with 3 year-regimen had been recently proven in preventing new clinical fracture. Although occurrences of ONJ have been reported to be rare with this drug administration, available data is very limited and long-term outcomes are lacking. We present a case of ONJ identified in an osteopenic patient with an intermittent but long standing sore mouth related to exposed mandibular bone. Once-yearly infusion of zoledronic acid used in the treatment of osteopenia may contribute to the spontaneous development of ONJ, especially in those presenting with multiple comorbidity factors. This report suggests the importance of health care professionals keeping abreast of new developments in this area and providing appropriate information to their patients. 展开更多
关键词 OSTEOPENIA Osteoporosis BISPHOSPHONATES OSTEONECROSIS LETROZOLE once-Yearly Zoledronic Acid ONJ ARONJ BRONJ
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关于单K_3-群的ONC-刻画(英文) 被引量:3
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作者 何立官 陈贵云 《数学进展》 CSCD 北大核心 2018年第6期821-832,共12页
设G为有限群,o_1(G)表示G中最高阶元素的阶,n_1(G)表示G中最高阶元素的个数.设G—共有r个o_1 (G)阶元,其中心化子的阶两两不同,并依次设这些中心化子的阶为c_1(G), c_2(G),…,c_r(G).令ON_1(G)={o_1(G);n_1(G)},ONC_1(G)={o_1(G);n_1(G)... 设G为有限群,o_1(G)表示G中最高阶元素的阶,n_1(G)表示G中最高阶元素的个数.设G—共有r个o_1 (G)阶元,其中心化子的阶两两不同,并依次设这些中心化子的阶为c_1(G), c_2(G),…,c_r(G).令ON_1(G)={o_1(G);n_1(G)},ONC_1(G)={o_1(G);n_1(G);c_1(G),c_2(G),…,c_r(G)}.我们分别称ON_1(G),ONC_1(G)为G的第1 ON-度量和第1 ONC-度量.本文用群的第1 ON-度量和第1 ONC-度量刻画了单K3-群,其中K3-群指的是阶刚好含3个不同素因子的群. 展开更多
关键词 单K3-群 第1 ON-度量 第1 0NC-度量 0NC-刻画
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基于改进YOLOv8n的轻量化精子检测算法研究与嵌入式实现
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作者 张鼎逆 庄天豪 李传江 《上海师范大学学报(自然科学版中英文)》 2025年第2期160-165,共6页
针对少精、弱精患者的家用精子检测仪嵌入式部署需求,提出一种基于改进you only look once(YOLO)v8n的轻量化精子检测算法.通过对YOLOv8n模型进行结构优化,在Neck层引入高效多分支尺度特征金字塔网络(EMBSFPN),在提高精度的同时保证了... 针对少精、弱精患者的家用精子检测仪嵌入式部署需求,提出一种基于改进you only look once(YOLO)v8n的轻量化精子检测算法.通过对YOLOv8n模型进行结构优化,在Neck层引入高效多分支尺度特征金字塔网络(EMBSFPN),在提高精度的同时保证了模型的轻量化.在检测头部分采用轻量级共享可变形卷积检测(LSDECD)头替换原来的检测头,大大减少了模型的参数量和运算量.实验结果表明,改进后的算法在精子检测任务上实现了良好的性能,平均精度提高了2.3%,模型运算量减少了26.8%,为嵌入式系统上的精子检测应用提供了一种有效的解决方案. 展开更多
关键词 改进you only look once(YOLO)v8 精子检测 轻量化
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超临界直流锅炉机组干湿转态柔性协调控制
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作者 邓拓宇 田亮 +2 位作者 贾梦颖 刘鑫屏 刘吉臻 《中国电机工程学报》 北大核心 2025年第8期3056-3066,I0017,共12页
直流锅炉机组在超低负荷灵活运行时面临干态和湿态间转换的控制难题。干态和湿态运行时的汽水流程差异导致控制对象结构不同,因此需要建立适用于干、湿态的机组动态模型;干态和湿态运行时的控制目标不同,导致干态和湿态的基本控制结构... 直流锅炉机组在超低负荷灵活运行时面临干态和湿态间转换的控制难题。干态和湿态运行时的汽水流程差异导致控制对象结构不同,因此需要建立适用于干、湿态的机组动态模型;干态和湿态运行时的控制目标不同,导致干态和湿态的基本控制结构不同。因此,针对干、湿态转换时对象结构、控制结构和控制目标均发生变化的特性,提出一种2层柔性协调控制系统。柔性控制底层沿用干、湿态运行的基本控制方式,顶层采用优化算法实时计算柔性因子,实现基本方式间的柔性切换。顶层算法的关键是给出转态不同阶段的响应矩阵和控制目标,并根据柔性因子分段优化。仿真实验表明,柔性协调控制方法能够实现系统干态、湿态间的自动转换,被控参数满足控制需求。 展开更多
关键词 直流锅炉 干湿态转换 柔性协调控制 柔性因子 优化算法
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秉持三重务实理念助力全球气候治理——海洋负排放国际大科学计划的科学认知与实践路径
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作者 焦念志 张传伦 +1 位作者 骆庭伟 刘纪化 《中国科学院院刊》 北大核心 2025年第10期1736-1744,共9页
应对气候变化是一项紧迫而长期的任务,仅靠减少温室气体排放无法实现《巴黎协定》温控目标,负排放是必然选择。海洋是地球上最大的活跃碳库、负排放潜力巨大,但尚无国际公认的实现路径。海洋负排放(Ocean Negative Carbon Emissions,ON... 应对气候变化是一项紧迫而长期的任务,仅靠减少温室气体排放无法实现《巴黎协定》温控目标,负排放是必然选择。海洋是地球上最大的活跃碳库、负排放潜力巨大,但尚无国际公认的实现路径。海洋负排放(Ocean Negative Carbon Emissions,ONCE)国际大科学计划立足微型生物碳泵(MCP)原创理论,综合已知海洋储碳机制(BCMS),提出合情、合理、合法的技术方案,构建可行、可靠、可期的实施路径,形成“理论—方法—标准—应用”链条。在此基础上,提出“三重务实”(Triple REAL)理念,涵盖技术方案(3R:技术合理、方案可行-ISO认证,推广可期)、实施原则(3E:生态友好、符合伦理、回报公平)、预期目标(3A:志向宏大、脚踏实地、目标可及)和治理框架(3L:合法合规、保护环境、权责明晰),搭建了具有系统性和可操作性的治理框架、构建了超越“三可”(可测量、可报告、可核查)的碳信用底层逻辑,为海洋碳汇纳入全球碳交易市场奠定基础、为全球气候治理提供科技支撑。 展开更多
关键词 海洋负排放 “三重务实”原则 全球气候治理
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