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循环STAiR18在多发性骨髓瘤患者微小残留监测中的临床应用研究
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作者 罗澜 罗吉 +2 位作者 吴应淼 姜涛 钟凌 《实用医院临床杂志》 2024年第6期59-65,共7页
目的探讨STAiR18作为无创监测新型标志物动态监测多发性骨髓瘤(MM)治疗缓解后体内微小残留病(MRD)的可能性和早诊复发的临床价值。方法收集初诊和治疗后随访患者的骨髓、血浆。采用ELISA测定血浆IL-6水平;提取骨髓浆细胞RNA和循环血浆R... 目的探讨STAiR18作为无创监测新型标志物动态监测多发性骨髓瘤(MM)治疗缓解后体内微小残留病(MRD)的可能性和早诊复发的临床价值。方法收集初诊和治疗后随访患者的骨髓、血浆。采用ELISA测定血浆IL-6水平;提取骨髓浆细胞RNA和循环血浆RNA,通过qRT-PCR分析STAiR18表达水平。化疗后定期随访评估无进展生存率(PFS)和生存期,监测STAiR18表达量。结果共收集46例MM患者,其骨髓浆细胞的STAiR18表达量是对照组的(4.97±1.24)倍(t=2.223,P=0.022),R-ISS分期越差,STAiR18表达量越高(Ⅰ、Ⅱ、Ⅲ期的相对表达量分别为2.49±1.43、5.47±1.14、6.93±1.23)。各期中,STAiR18表达量高于组内均值的患者的PFS均较低于组内均值患者的PFS差(χ^(2)=5.49,P=0.019;χ^(2)=15.96,P<0.05;χ^(2)=0.021,P=0.88)。初诊时,循环STAiR18表达量与骨髓浆细胞STAiR18的表达量显著相关(r=0.99,P<0.0001),也与相同时间点血浆IL-6浓度呈正相关(r=0.88,P<0.0001)。化疗后,11例患者达完全缓解,其中7例患者微小残留监测持续阴性,其STAiR18持续处于较低水平。而另4例患者循环STAiR18表达量逐渐增高,且在多参数流式细胞术MRD报阳前发生显著升高,平均提前4~8周。结论循环STAiR18有望成为MM患者MRD监测的新型无创标志物。 展开更多
关键词 LncRNA stair18 多发性骨髓瘤 微小残留监测 无创
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基于Stair−YOLOv7−tiny的煤矿井下输送带异物检测
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作者 梅晓虎 吕小强 雷萌 《工矿自动化》 CSCD 北大核心 2024年第8期99-104,111,共7页
针对现有煤矿井下输送带异物检测方法应对复杂场景适应性差、无法满足实时性和轻量化要求、处理尺寸差异较大异物时表现不佳的问题,基于轻量化YOLOv7−tiny模型进行改进,提出了一种Stair−YOLOv7−tiny模型,并将其用于煤矿井下输送带异物... 针对现有煤矿井下输送带异物检测方法应对复杂场景适应性差、无法满足实时性和轻量化要求、处理尺寸差异较大异物时表现不佳的问题,基于轻量化YOLOv7−tiny模型进行改进,提出了一种Stair−YOLOv7−tiny模型,并将其用于煤矿井下输送带异物检测。该模型在高效层聚合网络(ELAN)模块中添加特征拼接单元,形成阶梯ELAN(Stair−ELAN)模块,将不同层级的低维特征与高维特征进行融合,加强了特征层级间的直接联系,提升了信息捕获能力,增强了模型对不同尺度目标和复杂场景的适应性;针对检测头引入阶梯特征融合(Stair−fusion),形成阶梯检测头(Stair−head)模块,通过逐层融合不同分辨率的检测头特征,增强了中低分辨率检测头的特征表达能力,实现了特征信息的互补。实验结果表明:Stair−YOLOv7−tiny模型在输送带异物开源数据集CUMT−BelT上的检测效果优于CBAM−YOLOv5,YOLOv7−tiny及其轻量化模型,准确率、平均精度均值、召回率和精确率分别达98.5%,81.0%,82.2%和88.4%,检测速度为192.3帧/s;在某矿井下输送带监控视频分析中,Stair−YOLOv7−tiny模型未出现漏检或误检,实现了输送带异物的准确检测。 展开更多
关键词 输送带异物检测 YOLOv7−tiny 多尺度目标检测 stair−fusion 高效层聚合网络 检测头
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Stair climbing,genetic predisposition,and the risk of incident type 2 diabetes:A large population-based prospective cohort study
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作者 Yuanjue Wu Mengyun Luo +1 位作者 Xiao Tan Liangkai Chen 《Journal of Sport and Health Science》 SCIE CSCD 2023年第2期158-166,共9页
Background:Cross-sectional evidence and small-scale trials suggest positive effects of stair climbing on cardiometabolic disease and glucose regulation.However,few studies have examined the long-term association betwe... Background:Cross-sectional evidence and small-scale trials suggest positive effects of stair climbing on cardiometabolic disease and glucose regulation.However,few studies have examined the long-term association between stair climbing and the incidence of type 2 diabetes(T2D).We aimed to prospectively evaluate the association of stair climbing with T2D and assess modifications by genetic predisposition to T2D.Methods:We included 451,699 adults(mean age=56.3±8.1 years,mean±SD;55.2%females)without T2D at baseline in the UK Biobank and followed up to March 31,2021.Stair climbing information was collected through the touchscreen questionnaire.Genetic risk score for T2D consisted of 424 single nucleotide polymorphisms.Results:During a median follow up of 12.1 years,14,896 T2D cases were documented.Compared with participants who reported no stair climbing,those who climbed stairs regularly had a lower risk of incident T2D(10-50 steps/day:hazard ratio(HR)=0.95,95%confidence interval(95%CI):0.89-1.00;60-100 steps/day:HR=0.92,95%CI:0.87-0.98;110-150 steps/day:HR=0.86,95%CI:0.80-0.91;>150 steps/day:HR=0.93,95%CI:0.87-0.99,p for trend=0.0007).We observed a significant interaction between stair climbing and genetic risk score on the subsequent T2D risk(p for interaction=0.0004),where the risk of T2D showed a downward trend in subjects with low genetic risk and those who reported stair climbing activity of 110-150 steps/day appeared to have the lowest overall T2D risk among those with intermediate to high genetic risk.Conclusion:A higher number of stairs climbed at home was associated with lower T2D incidence risk,especially among individuals with a low genetic predisposition to T2D.These findings highlight that stair climbing,as incidental physical activity,offers a simple and low-cost complement to public health interventions for T2D prevention. 展开更多
关键词 COHORT Genetic risk score stair climbing Type 2 diabetes UK Biobank
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User Preference Survey on Staircase Rotation
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作者 Ping An Biao Wang 《Journal of Civil Engineering and Architecture》 2015年第7期836-844,共9页
Staircase is an important means of vertical transportation. Staircase design exerts a great influence on the aesthetics, transportation efficiency, user comfort and experience level. In this paper, a survey on the sta... Staircase is an important means of vertical transportation. Staircase design exerts a great influence on the aesthetics, transportation efficiency, user comfort and experience level. In this paper, a survey on the staircase rotation preference was conducted, based on the environment behavior studies. Different user frequencies of a pair of scissors stairs in the 2nd teaching building of North China University of Technology were analyzed. The psychological effect was evaluated and quantified, and the user preference on the two staircase rotations was then withdrawn. The survey found that the type of staircase with clockwise upstairs was much more preferred (78%) than the other staircase rotation anti-clock upstairs. Considering different genders, the female shows a 66% higher preference inclination of this type of staircase rotation than the male. To improve the transportation efficiency of the staircase in case of fire, the result of this paper can be very constructive for the evacuation staircase rotation choice for the high-rise buildings. 展开更多
关键词 Evacuation stairs staircase rotation user preference environmental behavior.
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基于Stair模式的大学生创新创业教育实践探索 被引量:3
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作者 周燕 黎鸿雁 +3 位作者 贾柠宁 李静 张佳景 马波 《高教学刊》 2019年第3期43-45,共3页
萨提亚模式作为一种积极向上、自信统一、内外和谐的心理学模式,非常适合融入大学生创新创教育及训练指导,帮助大学生迈向身心统一、充满信心地创新实践锻炼,激发学生的创新创业热情,促进了大学生创新创业意识、创新创业能力的提高,帮... 萨提亚模式作为一种积极向上、自信统一、内外和谐的心理学模式,非常适合融入大学生创新创教育及训练指导,帮助大学生迈向身心统一、充满信心地创新实践锻炼,激发学生的创新创业热情,促进了大学生创新创业意识、创新创业能力的提高,帮助学生在创新创业实践活动中寻找到属于自己内心的力量、勇气、喜悦,建立更和谐的团队关系,为大学生职业规划及未来职业发展奠定了基础。 展开更多
关键词 萨提亚(stair)模式 创新创业教育 创新实践 职业发展
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Stair evacuation simulation based on cellular automata considering evacuees' walk preferences 被引量:5
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作者 丁宁 张辉 +1 位作者 陈涛 Peter B.Luh 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期687-693,共7页
As a physical model, the cellular automata (CA) model is widely used in many areas, such as stair evacuation. However, existing CA models do not consider evacuees' walk preferences nor psychological status, and the... As a physical model, the cellular automata (CA) model is widely used in many areas, such as stair evacuation. However, existing CA models do not consider evacuees' walk preferences nor psychological status, and the structure of the basic model is unapplicable for the stair structure. This paper is to improve the stair evacuation simulation by addressing these issues, and a new cellular automata model is established. Several evacuees' walk preference and how evacuee's psychology influences their behaviors are introduced into this model. Evacuees' speeds will be influenced by these features. To validate this simulation, two fire drills held in two high-rise buildings are video-recorded. It is found that the simulation results are similar to the fire drill results. The structure of this model is simple, and it is easy to further develop and utilize in different buildings with various kinds of occupants. 展开更多
关键词 building evacuation stair simulation cellular automata walk preferences
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Analyzing floor-stair merging flow based on experiments and simulation 被引量:2
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作者 Yu Zhu Tao Chen +1 位作者 Ning Ding Wei-Cheng Fan 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期168-174,共7页
In most situations,staircase is the only egress to evacuate from high-rise buildings.The merging flow on the stair landing has a great influence on the evacuation efficiency.In this paper,we develop an improved cellul... In most situations,staircase is the only egress to evacuate from high-rise buildings.The merging flow on the stair landing has a great influence on the evacuation efficiency.In this paper,we develop an improved cellular automaton model to describe the merging behavior,and the model is validated by a series of real experiments.It is found that the flow rate of simulation results is similar to the drills,which means that the improved model is reasonable and can be used to describe the merging behavior on stairs.Furthermore,some scenarios with different door locations and building floor numbers are simulated by the model.The results show that(i)the best door location is next to the upward staircase;(ii)the total evacuation time and the building floor number are linearly related to each other;(iii)the pedestrians on upper floors have a negative influence on the evacuation flow rate. 展开更多
关键词 evacuation dynamics merging flow stair simulation cellular automaton high-rise buildings
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Comparison of gait properties during level walking and stair ascent and descent with varying loads 被引量:1
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作者 Tomohiro Demura Shin-ich Demura Sohee Shin 《Health》 2010年第12期1372-1376,共5页
This study aimed to compare gait properties during level walking and during stair ascent and descent with varying loads. Fifteen healthy young men (mean age: 22.1 ± 1.6 years) walked while holding four different ... This study aimed to compare gait properties during level walking and during stair ascent and descent with varying loads. Fifteen healthy young men (mean age: 22.1 ± 1.6 years) walked while holding four different loads relative to each subject’s body mass (0, 20, 40 and 60% of body mass: BM) on their backs. Stance time, swing time, and double support times were selected as gait parameters. All parameters showed a maximal value during stair ascent and a minimum value during level walking. Stance and double support times increased significan- tly with each load during level walking and during stair ascent and descent. In conclusion, st- air ascent and descent creates more unstable movement than level walking regardless of the weight of the load. The effect of loads on gait increases with the weight of the load and becomes obvious once the load exceeds 60% of BM. 展开更多
关键词 GAIT stair ASCENT stair DESCENT LOAD
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A Comparison of Pound's Poetic Ideas and Some Chinese Poetic Principles-Using the Translation of "The Jewel Stairs' Grievance" as a Case in Point
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作者 成婷 《海外英语》 2011年第9X期268-268,270,共2页
The prominent features of Li Bai's "The Jewel Stairs'Grievance" are precise diction;implicit meaning;an absent narrator;and a seamless unity of images and feelings.Pound's translation of it in Ca... The prominent features of Li Bai's "The Jewel Stairs'Grievance" are precise diction;implicit meaning;an absent narrator;and a seamless unity of images and feelings.Pound's translation of it in Cathay reveals some kind of connections between some Chinese poetic principals and Pound's individual poetics. 展开更多
关键词 POETIC PRINCIPALS POUND The Jewel stairs’Grievance
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The Jewel Stair’s Grievance(《玉阶之怨》)视觉意象的美学解读 被引量:1
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作者 张丽 《成都教育学院学报》 2006年第12期123-123,129,共2页
视觉意象是诗歌中最常见的一种意象,是诗人对所见之景象的语言描述,是外在之象与内在之意的一种有机联系,逼真地反映诗人的内心世界和作品的主题。文章从视觉意象出发,对英诗TheJewelStair’sGrievance(《玉阶之怨》)进行美学解读,以帮... 视觉意象是诗歌中最常见的一种意象,是诗人对所见之景象的语言描述,是外在之象与内在之意的一种有机联系,逼真地反映诗人的内心世界和作品的主题。文章从视觉意象出发,对英诗TheJewelStair’sGrievance(《玉阶之怨》)进行美学解读,以帮助学习者更好地欣赏诗歌,领会作品主题,增强诗歌的审美情趣。 展开更多
关键词 视觉意缸 美学解读 《玉阶之怨》 《玉阶怨》
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APPLICATIONS OF STAIR MATRICES AND THEIR GENERALIZATIONS TO ITERATIVE METHODS
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作者 邵新慧 沈海龙 李长军 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第8期1115-1121,共7页
Stair matrices and their generalizations are introduced. The definitions and some properties of the matrices were first given by Lu Hao. This class of matrices provide bases of matrix splittings for iterative methods.... Stair matrices and their generalizations are introduced. The definitions and some properties of the matrices were first given by Lu Hao. This class of matrices provide bases of matrix splittings for iterative methods. The remarkable feature of iterative methods based on the new class of matrices is that the methods are easily implemented for parallel computation. In particular, a generalization of the accelerated overrelaxation method (GAOR) is introduced. Some theories of the AOR method are extended to the generalized method to include a wide class of matrices. The convergence of the new method is derived for Hermitian positive definite matrices. Finally, some examples are given in order to show the superiority of the new method. 展开更多
关键词 stair matrices iterative method parallel computation generalization of the AOR method
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A New Copper(Ⅰ) Iodide Coordination Polymer Incorporating Cu_2I_2 Double-stranded Stair: Synthesis, Crystal Structure and Luminescent Property
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作者 高兰 吴建炎 +6 位作者 李梦雅 章凌 张萍 吴强芳 蔡晓庆 陈锋涛 章世深 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第6期885-889,共5页
A new coordination compound, [(CuI)(Btd)]n (1, Btd = 2,1,3-benzothiadiazole), was obtained at room temperature by the reaction of 2,1,3-benzothiadiazole with CuI and KI saturated aqueous solution. It was charact... A new coordination compound, [(CuI)(Btd)]n (1, Btd = 2,1,3-benzothiadiazole), was obtained at room temperature by the reaction of 2,1,3-benzothiadiazole with CuI and KI saturated aqueous solution. It was characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction analysis and photoluminescence. The complex crystallizes in the triclinic Pi space group, with a = 4.1620(6), b = 10.4590(15), c = 10.5052(15) A, a = 69.310(2), β = 83.608(2), γ = 78.873(2)°, V = 419.30(10) A3, Z = 2, C6H4N2SCuI, Mr = 326.61, Dc = 2.587 g/cm^3, F(000) = 304 and/^(MoKa) = 6.464 mm-1. The final R = 0.0418 and wR = 0.0936 for 1451 observed reflections with 1 〉 2σ(I) and R = 0.0422 and wR = 0.0939 for all data. In the complex, the Cu atoms are coordinated by one nitrogen atom and three iodine atoms to form a double-stranded stair, and such stairs are further linked to build a 2D framework via C-H…I interactions. 展开更多
关键词 copper(I) iodide double-stranded stair luminescent
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Practical Use of Stairs to Assess Fitness, Prescribe and Perform Physical Activity Training
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作者 Jasem Ramadan Al Kandari Salman Mohammad +2 位作者 Ruqayyah Al-Hashem Girma Telahoun Mario Barac-Nieto 《Health》 CAS 2016年第13期1402-1410,共9页
Aim: Evaluating climbing stairs for prescription and implementation of physical activity regimes. Methods: Healthy females (F, n = 14), and males (M, n = 15) participated. By climbing 100 steps of stairs with 0.173 m ... Aim: Evaluating climbing stairs for prescription and implementation of physical activity regimes. Methods: Healthy females (F, n = 14), and males (M, n = 15) participated. By climbing 100 steps of stairs with 0.173 m height, Heart rate (HR) and oxygen uptake were measured throughout the floors;Blood pressure (BP) was measured at ground and the 5th floors only. Results: Energy increased from 2 to 7.6 was metabolic equivalents (METs = 3.5 ml O<sub>2</sub>/min.kg) at 17.3 m elevation in 2 min. at the 5th floor, and percent Heart Rate Reserve (%HRR) was 66.17% in F and 48.7% in M, proportional to their aerobic efforts. Average climbing efficiency was 15.8 ± 2.3% (n = 29). Aerobic capacity estimated dividing the highest work rate (17.3 Kg.m/2min.Kg × 0.00239 = 0.0207 Kcal/min.Kg), by fractional effort (F = 0.6617, M = 0.487) and fractional efficiency (0.158), at 5 Kcal/L O2 was 0.040 in F and 0.054 L O2/Kg.min in M. Minimum training intensity reached at the 3rd floor by F. In M the highest %HRR reached was 48.7% at the 5th floor, insufficient for training. Conclusions: Stairs used for submaximal evaluation of aerobic capacity and for target intensity prescription. Training, levels climbed, repetitions per day (if 5, 100 Kcal per day, ascending) and number of days/week are adjusted. Full regime requires up to 7.6 METs, a total of 532 and 140 MET.min/week ascending and descending, respectively. Intensities >7.6 MET, climbing rate should be >8.65 m/min. Limiting ascent to 1 (3.5 METs) or 2 (5.5 METs) floors or only descents (2 - 3 METs) may be used for unfit subjects. This method is useful for those with no access to sophisticated facilities. 展开更多
关键词 stair Climbing DESCENT Heart Rate Reserve Aerobic Effort Oxygen Cost Work Output Efficiency Aerobic Capacity Exercise Prescription TRAINING
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Form Art and Function Analysis of Outdoor Stairs
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作者 MENG Lingshuai 《Journal of Landscape Research》 2021年第2期83-88,共6页
Stairs are an important structural component in the architectural space design.It not only serves as a link between landscapes,but also a highlight of the space.Interpretation of stairs can be carried out from the for... Stairs are an important structural component in the architectural space design.It not only serves as a link between landscapes,but also a highlight of the space.Interpretation of stairs can be carried out from the form and function of stairs.This paper mainly takes the outdoor stairs as the research object,which is a building component to solve the vertical traffic function of the building,and selects some stairs designs worldwide for the analysis.Focusing on architectural design,the study investigates the expression form of each component of the outdoor stairs,and explores the diversified designs of the stairs.The paper urges designers to pay close attention to the problems of stair design in essence,to deeply understand the forms and methods of stair expression,to expand the breadth of architectural design thinking,to pursue in-depth understanding of the inherent laws of building generation,and to improve the quality of architecture. 展开更多
关键词 Outdoor stairs Form art Form and structure
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A Star-Wheel Stair-Climbing Wheelchair
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作者 ZHANG Li WU Bo +3 位作者 JIN Ai-min JIANG Shi-hong ZHENG Yu-fei ZHANG Shuai 《Computer Aided Drafting,Design and Manufacturing》 2014年第3期53-56,共4页
In order to achieve a wheelchair climb stairs function, this paper designs a star-wheel stair-climbing mechanism. Through the effect of the lock coupling, the star-wheel stair-climbing mechanism is formed to be fixed ... In order to achieve a wheelchair climb stairs function, this paper designs a star-wheel stair-climbing mechanism. Through the effect of the lock coupling, the star-wheel stair-climbing mechanism is formed to be fixed axis gear train or planetary gear train achieving flat-walking and stair-climbing functions. Crossing obstacle analysis obtains the maximum height and minimum width of obstacle which the wheelchair can cross. Stress-strain analysis in Solidworks simulation is performed to verify material strength. 展开更多
关键词 stair-climbing wheelchair star-wheel mechanism crossing obstacle analysis Solidworks simulation analysis
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Oxygen uptake response to switching stairs exercise by non-parametric modeling
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作者 Hairong Yu Chenyu Zhang +2 位作者 Kai Cao Hamzah M.Alqudah Steven Weidong Su 《Control Theory and Technology》 EI CSCD 2024年第2期315-325,共11页
Oxygen uptake plays a crucial role in the evaluation of endurance performance during exercise and is extensively utilized for metabolic assessment. This study records the oxygen uptake during the exercise phase (i.e.,... Oxygen uptake plays a crucial role in the evaluation of endurance performance during exercise and is extensively utilized for metabolic assessment. This study records the oxygen uptake during the exercise phase (i.e., ascending or descending) of the stair exercise, utilizing an experimental dataset that includes ten participants and covers various exercise periods. Based on the designed experiment protocol, a non-parametric modeling method with kernel-based regularization is generally applied to estimate the oxygen uptake changes during the switching stairs exercise, which closely resembles daily life activities. The modeling results indicate the effectiveness of the non-parametric modeling approach when compared to fixed-order models in terms of accuracy, stability, and compatibility. The influence of exercise duration on estimated fitness reveals that the model of the phase-oxygen uptake system is not time-invariant related to respiratory metabolism regulation and muscle fatigue. Consequently, it allows us to study the humans’ conversion mechanism at different metabolic rates and facilitates the standardization and development of exercise prescriptions. 展开更多
关键词 Non-parametric modeling Interval stair training exercise Kernel method.Cardiorespiratory response Oxygen uptake
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Obstacle detection and autonomous stair climbing of a miniature jumping robot
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作者 Yaning Zhang Jun Zhang +2 位作者 Bohuai Chen Haoyun Chen Aiguo Song 《Biomimetic Intelligence & Robotics》 2023年第1期11-21,共11页
Miniature jumping robots(MJRs)have difficulty executing autonomous movements in unstructured environments with obstacles because of their limited perception and computing resources.This study investigates the obstacle... Miniature jumping robots(MJRs)have difficulty executing autonomous movements in unstructured environments with obstacles because of their limited perception and computing resources.This study investigates the obstacle detection and autonomous stair climbing methods for MJRs.We propose an obstacle detection method based on a combination of attitude and distance detections,as well as MJRs’motion.A MEMS inertial sensor collects the yaw angle of the robot,and a ranging sensor senses the distance between the robot and the obstacle to estimate the size of the obstacle.We also propose an autonomous stair climbing algorithm based on the obstacle detection method.The robot can detect the height and width of stairs and its position relative to the stairs and then repeatedly jump to climb them step by step.Moreover,the height,width,and position are sent to a control terminal through a wireless sensor network to update the information regarding the MJR and stairs in a control interface.Furthermore,we conduct stair detection,modeling,and stair climbing experiments on the MJR and obtain acceptable precisions for autonomous obstacle negotiation.Thus,the proposed obstacle detection and stair climbing methods can enhance the locomotion capability of the MJR in environmental monitoring,search and rescue,etc. 展开更多
关键词 Jumping robot Obstacle detection Obstacle modeling Active perception Autonomous stair climbing
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基于政府信任视角的政府绩效评估创新及STAIR模型的引介 被引量:4
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作者 陈超阳 《行政论坛》 CSSCI 北大核心 2015年第2期65-68,共4页
政府信任是公民对政府或政治体系将实现符合他们预期结果的一种信心,是政治支持的重要组成部分之一,构成了政治制度的合法性基础。政府绩效是政府在运行过程中自身效率与效能的体现,也是政府在政治、经济、社会与文化等各方面采取行动... 政府信任是公民对政府或政治体系将实现符合他们预期结果的一种信心,是政治支持的重要组成部分之一,构成了政治制度的合法性基础。政府绩效是政府在运行过程中自身效率与效能的体现,也是政府在政治、经济、社会与文化等各方面采取行动的结果。政府绩效与政府信任两者之间关系密切,前者构成了后者的利益基础和重要来源。STAIR模型即"战略—目标—指标—执行—结果"模型以战略为导向,探讨如何整合绩效评估过程的各个环节,实现政府绩效评估的战略化和系统化,改善政府绩效,提高公众信任度。 展开更多
关键词 政府信任 政府绩效 绩效评估 stair模型
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地下隧道竖向疏散现场试验研究
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作者 陈俊伟 李姚 +4 位作者 徐志胜 谢宝超 楚坤坤 赵家明 于子涵 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第9期3684-3695,共12页
近年来,隧道的疏散设计中普遍应用竖向疏散模式,但该模式的安全性缺少真实试验数据支撑和验证。为探究隧道竖向疏散模式下的人员疏散行为特征及关键参数,采用现场试验的方法,在某隧道内搭建火灾时的交通堵塞场景,组织188名参与者(109名... 近年来,隧道的疏散设计中普遍应用竖向疏散模式,但该模式的安全性缺少真实试验数据支撑和验证。为探究隧道竖向疏散模式下的人员疏散行为特征及关键参数,采用现场试验的方法,在某隧道内搭建火灾时的交通堵塞场景,组织188名参与者(109名男性,79名女性)开展大规模人群疏散研究,针对人员疏散时间、疏散行走速度、疏散楼梯人员通行能力、疏散楼梯盖板开启时间等参数进行分析。研究结果表明:1)隧道火灾时,人员疏散受到隧道熟悉度和疏散引导的显著影响,在紧急疏散过程中更容易发生拥堵,疏散引导可极大地改善人员的出口及路径选择,提高疏散效率。2)交通堵塞状态下,人员疏散行走速度因隧道熟悉度的提高和疏散引导而显著提高。行车道上,男性和女性的平均速度分别由1.38 m/s、1.39 m/s提高至1.94 m/s、1.99 m/s。但在下部安全疏散通道内,参与者出现懈怠和放松的情绪,平均疏散行走速度会略有降低。应考虑在疏散通道内设置一些警示标志以督促引导人员疏散。3)入口宽度为1.09 m的疏散楼梯的最大人员通行能力为38人/min;男性参与者开启楼梯盖板的平均时间为7.5 s,女性参与者开启楼梯盖板的平均时间为12.6 s,相比于女性,男性参与者更容易打开楼梯盖板。研究结果可为隧道疏散逃生方案设计、运营管理提供真实试验数据参考,提高隧道防灾疏散水平。 展开更多
关键词 隧道火灾 隧道逃生 疏散楼梯 现场试验 疏散能力
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阿基米德螺线变形轮的设计与研究
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作者 张恩惠 任士超 赵长荣 《机械传动》 北大核心 2024年第10期68-74,共7页
针对轮组式、轮履复合式和轮腿复合式等传统爬楼机构对楼梯适应能力不足以及体积笨重的问题,以攀爬楼梯为首要任务和设计目的,提出了一种新型楼梯越障机构——阿基米德螺线变形轮。该变形轮不仅能够较好地适应楼梯这种复杂环境,而且结... 针对轮组式、轮履复合式和轮腿复合式等传统爬楼机构对楼梯适应能力不足以及体积笨重的问题,以攀爬楼梯为首要任务和设计目的,提出了一种新型楼梯越障机构——阿基米德螺线变形轮。该变形轮不仅能够较好地适应楼梯这种复杂环境,而且结合了轮式行进机构的强机动性与螺线行进机构的优良越障性。使用SoildWorks软件对变形轮机构和总体装配方案进行设计;根据运动环境和越障过程对变形轮进行参数计算和数据分析,优化了变形轮翻越连续台阶过程;最后,应用Adams软件对变形轮越障过程进行仿真分析,并将行星轮和变形轮进行对比仿真,证明了设计与研究的有效性。仿真结果证明,所设计的变形轮具有较强的机动性与稳定性。 展开更多
关键词 阿基米德螺线 变形轮 楼梯越障机构 稳定性
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