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WTO体制的利益平衡体系与机制 认领
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作者 朱淑娣 《河南财经政法大学学报》 2020年第2期117-124,共8页
WTO体制的利益体系是由WTO的申请方与成员方,成员方之间,尤其是发达成员与发展中成员之间通过利益平衡机制博弈形成的,以权利、义务平衡为内容的利益平衡性体系,而WTO协议就是该利益平衡体系的法律确定形式与利益平衡博弈的游戏规则,因... WTO体制的利益体系是由WTO的申请方与成员方,成员方之间,尤其是发达成员与发展中成员之间通过利益平衡机制博弈形成的,以权利、义务平衡为内容的利益平衡性体系,而WTO协议就是该利益平衡体系的法律确定形式与利益平衡博弈的游戏规则,因为WTO协议及其生成、演变与实施过程,无不昭示WTO体制的运行规律是生成利益平衡、利益平衡演变与维持利益平衡。此观点对于WTO体制内的各类谈判,以及国际贸易争端解决应有顶级的价值导向意义。 展开更多
关键词 WTO体制 利益体系 平衡性 利益平衡性体系
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Effects of virtual reality balance games combined with muscle strength training on balance function and motor ability of Parkinson's patients 认领
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作者 Li-Chun Sun Rong Chen 《海南医科大学学报:英文版》 2020年第9期15-18,共4页
Objective To investigate the effects of virtual reality balance games combined with strengthening muscle training on balance function and exercise capacity in patients with Parkinson's disease.Methods Sixty patien... Objective To investigate the effects of virtual reality balance games combined with strengthening muscle training on balance function and exercise capacity in patients with Parkinson's disease.Methods Sixty patients with Parkinson's disease were selected from January 2018 to October 2019.The random number table method was divided into the control group(n=30)and the observation group(n=30).Both groups were given conventional drugs and For rehabilitation training,the observation group was given a virtual reality balance game combined with strengthening muscle training.The upper limbs,lower limbs,balance function,comprehensive rehabilitation effect and daily living ability were compared before and after training.Results After training,the Brunnstrom score,FMA-UE,FMA-LE score,and cadence score of the two groups of patients increased.The common contraction rate(CR)of the biceps brachii in elbow flexion and the three heads of the brachii in elbow extension Muscle CR,standing walking test,10m walking test,reduced left and right step difference,and the observation group was better than the control group,which was significant(P<0.05).Conclusion Patients with Parkinson's disease have improved their upper and lower extremity motor capacity and balance function through virtual reality balance games combined with strengthening muscle training,which can improve the overall rehabilitation effect and ability of daily living. 展开更多
关键词 Parkinson's disease Balance movement Virtual reality balance games Strengthen muscle strength trainin
Reducing Sharp Fluctuations in Body Temperature and Optimizing Production Index of Broilers Using Dietary Electrolytes 认领
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作者 Ibukun Olukorede Popoola Oluwabukola Rashidat Popoola +2 位作者 Oluwaseyi Olamide Olajide Akinyemi Alaba Adeyemi Queenesther Tolu Alegbejo 《动物科学期刊(英文)》 2020年第2期266-277,共12页
A degree centigrade fall or rise in body temperature of broiler chickens is sufficient to reduce performance, alter sound physiological state and divert nutritional metabolism in quest for ensuring thermal balance. Th... A degree centigrade fall or rise in body temperature of broiler chickens is sufficient to reduce performance, alter sound physiological state and divert nutritional metabolism in quest for ensuring thermal balance. Thermoregulatory mechanisms of newly hatched chicks are poorly developed, and fluctuations in brooding temperature coupled with severe environmental temperatures in the tropics could threaten the survivability, production and economic integrity of fast-growing strains of broilers. However, information on the effect of sharp fluctuations in body temperature on nutrient intake and European production index (EPI) of broilers fed dietary electrolytes is scanty and thus investigated. Using a total of 300, one-day-old unsexed broiler chicks (Arbor Acre) that were randomly allotted to six dietary treatments (T1-210, T2-240, T3270, T4-300, T5-330 and T6-360 mEq/kg electrolyte balance), data on performance characteristics and their correlations with body temperature and EPI at prestarter, starter and finisher phases were determined using standard procedures. Data were analysed using descriptive statistics and ANOVA at α = 0.05. At prestarter phase, feed intake (FI) had a strong and positive relationship with protein intake (r = 1.00;p < 0.01), EPI (r = 0.96;p < 0.01) and potassium (K) intake (r = 0.66;p < 0.01), but was negatively correlated with temperature change (r = ?0.39;p < 0.05). However, FI was not significantly correlated with body weight (BW), body weight gain (BWG), sodium (Na) and water intake. At starter phase, EPI was positively correlated to K intake (r = 0.38;p < 0.05), but not Na and chloride (Cl) intake. European production index of starter chicks could be enhanced by increasing the level of K intake through dietary supplementation up to 1.02%. Weight gain was adversely affected by sharp changes in temperature at finisher phase. Increase in water intake may not be a remedial tool in lowering sharp fluctuations in body temperature. However, sharp fluctuation in body temperature of broilers was 展开更多
关键词 Temperature Change BROILERS European PRODUCTION INDEX DIETARY Electrolyte Balance Heat Stress
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Design and Analysis of a Metallic Uranium Reactor Type-Pump Using the Magnesiothermy Process 认领
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作者 Munir Dides José Hernández Luis Olivares 《核科学与技术国际期刊(英文)》 2020年第1期9-22,共14页
This paper shows a methodology to obtain metallic uranium through a magnesiothermy process. Chile has two experimental reactors operated by the “Chilean Nuclear Energy Commission” (CCHEN). One is 5 MW and the other ... This paper shows a methodology to obtain metallic uranium through a magnesiothermy process. Chile has two experimental reactors operated by the “Chilean Nuclear Energy Commission” (CCHEN). One is 5 MW and the other is 10 MW. In order to fulfill international agreements about nuclear energy for testing purposes of these reactors, CChEN purchased 19.9% enriched uranium hexafluoride, also known as the limit of Low Enriched Uranium (LEU). Due to the capacity of these reactors, they need high-density uranium compounds for their fuel, in order to work with LEU. For this reason, the uranium needs a previous conversion into metallic uranium. The conversion laboratory carried out experiences for reduction of UF4 with Mg. The main purpose of this study was to analyze the operating conditions under which the reduction reaction takes place, the designed method and the equipment and materials used. The raw material used was dehydrated UF4, prepared by electrolytic reduction and commercial purity Magnesium. The reaction took place in a cylindrical reactor made of low alloy steel, with a conic section in the lower part. The internal zone was coated with a 2.5 cm thick layer of CaF2. The process started by applying external heating, according to a heating program, developed specially for this purpose. The reduction reaction took place starting at 650°C. The result was a cylinder of uranium metal and MgF2 slag. The crossed cut uranium cylinder showed a smooth and homogeneous surface without inclusions of slag, pores or blisters. The yield of the reaction was of the order of 75% with respect to the expected theoretical value. The uranium cone obtained fulfilled the required conditions for source material for nuclear fuel fabrication, with a uranium content of 97.5%. 展开更多
关键词 Magnesiothermy METALLIC URANIUM Heat BALANCE
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Climate and Water Balance Changes in the Kinneret Watershed: A Review 认领
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作者 Moshe Gophen 《现代水文学期刊(英文)》 2020年第2期21-29,共9页
Regional Climate Change studied during 1950-2019 aimed at enhancement of aridity was indicated recently in the Lake Kinneret (Israel) watershed. Climate change was indicated by: Higher periodical frequency of negative... Regional Climate Change studied during 1950-2019 aimed at enhancement of aridity was indicated recently in the Lake Kinneret (Israel) watershed. Climate change was indicated by: Higher periodical frequency of negative SPI Values (Standard Precipitation Index), decline of Precipitation regime and River flow inputs that was followed by decline of Lake Kinneret WL and Elevation of ET regime. Nevertheless aridity enhanced the opposite, decline of ET capacities. Underground flows indicated outputs enhancement. The temporal decline of air temperature during 1940-1980 probably due to the change of ALBEDO Factor was twisted later into regional temperature elevation. During the 1950s, old lake Hula and surrounding wetlands were drained and water cover surface was converted to plant cover, which enhanced sunlight energy reflection. Followed eventual climate change, management legislations were a reduction of water allocation for agricultural irrigation. A recent public dispute has indicated contradicted conclusions as causation for WL decline in Lake Kinneret: 1) Enhancement of Agricultural water consumption in the Upper Jordan Watershed and 2) Climate change-aridity enhancement. This paper confirms the second conclusion. 展开更多
关键词 Kinneret Hula WATERSHED CLIMATE CHANGE Water BALANCE AGRICULTURE
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Comprehensive Analytical Study of the Greenhouse Effect of the Atmosphere 认领
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作者 Peter Stallinga 《大气和气候科学(英文)》 2020年第1期40-80,共41页
Climate change is an important societal issue. Large effort in society is spent on addressing it. For adequate measures, it is important that the phenomenon of climate change is well understood, especially the effect ... Climate change is an important societal issue. Large effort in society is spent on addressing it. For adequate measures, it is important that the phenomenon of climate change is well understood, especially the effect of adding carbon dioxide to the atmosphere. In this work, a theoretical fully analytical study is presented of the so-called greenhouse effect of carbon dioxide. The effect of this gas in the atmosphere itself was already determined as being of little importance based on empirical analysis. In the current work, the effect is studied both phenomenologically and analytically. In a first attempt of energy transfer by radiation only, it is solved by ideal-gas-law equations and the atmosphere is divided into an infinite number of layers each absorbing and reemitting infrared radiation (surpassing the classical Beer-Lambert analysis of absorption). The result is that the exact structure of the atmosphere is irrelevant for the analysis;we might as well keep the two-box model for any analytical approach. However, the results are unsatisfactory in that they cannot explain the profile of the atmosphere. In a new approach, the atmosphere is solved by taking both radiative as well as thermodynamic processes into account. The model fully fits the empirical data and an analytical equation is given for the atmospheric behavior. Upper limits are found for the greenhouse effect ranging from zero to a couple of mK per ppm CO2. It is shown that it cannot explain the observed correlation of carbon dioxide and surface temperature. This correlation, however, is readily explained by Henry’s Law (outgassing of oceans), with other phenomena insignificant. Finally, while the greenhouse effect can thus, in a rudimentary way, explain the behavior of the atmosphere of Earth, it fails describing other atmospheres such as that of Mars. Moreover, looking at three cities in Spain, it is found that radiation balances only cannot explain the temperature of these cities. Finally, three data sets with different time scales (60 years, 展开更多
关键词 GREENHOUSE Effect THERMODYNAMICS Radiation BALANCE Correlation FEEDBACK Water Carbon Dioxide MARS VENUS Earth
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虚拟现实平衡游戏联合强化肌力训练对帕金森病患者平衡功能及运动能力的影响 认领
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作者 孙丽春 陈蓉 《海南医学院学报》 CAS 2020年第9期655-658,663共5页
目的:探究虚拟现实平衡游戏联合强化肌力训练对帕金森病患者平衡功能及运动能力的影响。方法:选取60例帕金森病患者为研究对象,随机分为对照组(n=30)与观察组(n=30),两组均给予常规药物与康复训练,观察组同时给予虚拟现实平衡游戏联合... 目的:探究虚拟现实平衡游戏联合强化肌力训练对帕金森病患者平衡功能及运动能力的影响。方法:选取60例帕金森病患者为研究对象,随机分为对照组(n=30)与观察组(n=30),两组均给予常规药物与康复训练,观察组同时给予虚拟现实平衡游戏联合强化肌力训练。比较训练前、后的上肢、下肢、平衡功能、综合康复效果和日常生活活动能力。结果:训练后两组Brunnstrom评分、FMA-UE、FMA-LE评分、步频评分升高,患肘屈曲时肱二头肌共同收缩率(common contraction rate,CR)、患肘伸展时肱三头肌CR、起立行走测试、10 m步行测试、左右步长差降低,且观察组优于对照组,差异有统计学意义(P<0.05)。结论:帕金森病患者经虚拟现实平衡游戏联合强化肌力训练上肢及下肢运动能力、平衡功能均改善,可提高综合康复效果和日常生活活动能力。 展开更多
关键词 帕金森病 平衡 运动 虚拟现实平衡游戏 强化肌力训练
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Probe chiral magnetic effect with signed balance function 认领
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作者 A.H.Tang 《中国物理C:英文版》 SCIE CAS CSCD 2020年第5期43-55,共13页
In this paper a pair of observables are proposed as alternative ways,by examining the fluctuation of net momentum-ordering of charged pairs,to study the charge separation induced by the Chiral Magnetic Effect(CME)in r... In this paper a pair of observables are proposed as alternative ways,by examining the fluctuation of net momentum-ordering of charged pairs,to study the charge separation induced by the Chiral Magnetic Effect(CME)in relativistic heavy ion collisions.They are,the out-of-plane to in-plane ratio of fluctuation of the difference between signed balance functions measured in pair’s rest frame,and the ratio of it to similar measurement made in the laboratory frame.Both observables have been studied with simulations including flow-related backgrounds,and for the first time,backgrounds that are related to resonance's global spin alignment.The two observables have similar positive responses to signal,and opposite,limited responses to identifiable backgrounds arising from resonance flow and spin alignment.Both observables have also been tested with two realistic models,namely,a multi-phase transport(AMPT)model and the anomalous-viscous fluid dynamics(AVFD)model.These two observables,when cross examined,will provide useful insights in the study of CME-induced charge separation. 展开更多
关键词 CHIRAL magnetic effect BALANCE FUNCTION SIGNED BALANCE FUNCTION heavy ion COLLISIONS momentum ORDERING
Climate Change, Regional Water Balance and Land Use Policy, in the Watershed of Lake Kinneret (Israel) 认领
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作者 Moshe Gophen Moshe Meron +2 位作者 Valerie Levin-Orlov Yosef Tsipris Mordechay Peres 《生态学期刊(英文)》 2020年第4期200-224,共25页
Long term data record (1944-2018) of climatological conditions in the Lake Kinneret and its watershed ecosystems was statistically evaluated and the impact of Anthropogenic operations was included as well. Precipitati... Long term data record (1944-2018) of climatological conditions in the Lake Kinneret and its watershed ecosystems was statistically evaluated and the impact of Anthropogenic operations was included as well. Precipitation input source is obviously uncontrolled natural component whilst the other three regional water outflows pathways are under anthropogenic control: Evapo-transpiration (ET), Runoff and underground flows. Indications for climate change expressed as air warming with consequences on regional (watershed and the lake) water resources and consumption capacities policy in the drainage basin and in the Lake are discussed. The decline of air temperature from 1940 to 1970s is probably due to a change in the Albedo effect. After the decline air temperature was twisted towards elevation. Climate change caused a decline in rainfall, followed by a reduction of Jordan and other river discharges and underground flows, accompanied by a decline of WL. With respect to climate change, water allocation for agricultural consumption was shrunk. 展开更多
关键词 WATERSHED CLIMATE Change REGIONAL WATER BALANCE Kinneret WATER Level
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Optimization Analysis of Correction Tape Box Compounding Cavity Runner Balance Based on Moldflow 认领
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作者 Hongbing Wang Chunhua Sun 《世界工程和技术(英文)》 2020年第1期42-49,共8页
Aiming at the problem of runner unbalance in the compounding cavity of the upper and lower cover of the correction tape box, the plastic injection analysis software Moldflow was used to optimize runner balance. First,... Aiming at the problem of runner unbalance in the compounding cavity of the upper and lower cover of the correction tape box, the plastic injection analysis software Moldflow was used to optimize runner balance. First, the 3D modeling software Proe was used to establish the geometric model of the upper and lower cover of the correction tape box, and introduced into the plastic injection analysis software Moldflow. Secondly, the upper and the lower cover of the correction tape box were meshed and the initial gating system was designed in Moldflow. Filling analysis of the initial scheme of the correction tape box combined cavity showed that the runner of the melt was not balanced in the mold cavity. Finally, the runner balance optimization analysis of the cavities was carried out. Through optimization, the time unbalance rate of the melt in the mold cavity decreased from 28.6% to 0.7%, the pressure unbalance rate decreased from 42.0% to 4.2%, and the pressure distribution in the cavity was more uniform in the whole injection process. 展开更多
关键词 COMPOUNDING CAVITY RUNNER BALANCE Optimization
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Influence of Copper Deficit on Structural and Metabolic Features of Myocardium of Rats in Conditions of ThyroidHypofunction 认领
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作者 Tetyana Guranych Nataliya Voronych-Semchenko Mykola Bagriy 《药剂与药理学:英文版》 2020年第1期1-6,共6页
The research was carried on 60 rats,which were divided into two experimental groups animals with thyroid hypofunction against iodine deficiency and on the background of combined iodine and copper deficit.The control g... The research was carried on 60 rats,which were divided into two experimental groups animals with thyroid hypofunction against iodine deficiency and on the background of combined iodine and copper deficit.The control group included 30 intact rats.For evaluation of copper balance its content was determined in erythrocyte mass and myocardium.Prooxidant-antioxidant system was examined by the level of peroxide oxidation of proteins and lipids and due to the activity of antioxidant enzymes.Structural features of the myocardium were examined by light-optical microscopy with subsequent morphometry.In the result of the experiment in rats with thyroid hypofunction on the background of combined iodine and copper deficit the redistribution of copper content in the studied tissues was established(accumulation in blood).The results of the study confirm the activation of oxygen-dependent processes in the myocardium of experimental animals,primarily due to peroxide oxidation of proteins,which is especially manifested in the context of combined iodine and copper deficiency.Metabolic changes in the myocardium were confirmed by histology.So,the development of thyroid hypofunction on the background of combined iodine and copper deficiency increases the probability of cardiovascular pathology due to disorders of prooxidant-antioxidant balance and structural changes in the myocardium. 展开更多
关键词 THYROID HYPOFUNCTION COPPER DEFICIT prooxidant-antioxidant balance structure of MYOCARDIUM
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双重任务训练对养老院老年人步态与平衡功能的影响 认领
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作者 张慧鑫 张瑞丽 +4 位作者 李玉芝 于虹 陈健新 李慧娟 吴景梅 《护理学杂志》 CSCD 北大核心 2020年第2期94-98,共5页
目的探讨双重任务训练对养老院老年人步态与平衡改善的效果。方法将养老院30例老年人按照随机数字表法分为观察组与对照组各15人。对照组按常规进行回春医疗保健操训练,观察组在常规训练基础上开展双重任务训练。于干预前和干预6周后进... 目的探讨双重任务训练对养老院老年人步态与平衡改善的效果。方法将养老院30例老年人按照随机数字表法分为观察组与对照组各15人。对照组按常规进行回春医疗保健操训练,观察组在常规训练基础上开展双重任务训练。于干预前和干预6周后进行步态参数测试及平衡测试。结果干预后,观察组步速、步长、双重任务步长、起立行走试验用时和双重任务起立行走试验用时、平衡功能评分显著优于对照组(P<0.05,P<0.01),两组双重任务步速及ABC平衡信心评分差异无统计学意义(均P>0.05)。结论双重任务训练可改善养老院老年人的步态及综合平衡能力,但对其害怕跌倒心理的改善作用不显著。 展开更多
关键词 老年人 双重任务 步态 平衡 害怕跌倒 运动 平衡能力
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文章速递下肢步行机器辅助训练装置训练对脑卒中患者躯干控制和平衡功能的影响 认领
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作者 宋梅思 吴丹丽 +5 位作者 李奎 马晓丹 陈培荣 沈鲁希 范萌 黄鹏 《按摩与康复医学》 2020年第21期41-43,共3页
目的:探讨下肢步行机器辅助训练装置训练对改善脑卒中患者躯干控制和平衡功能的影响。方法:选取2018年10月~2019年11月在中山大学附属第三医院康复科进行康复治疗的脑卒中偏瘫患者48例,并按随机数字表法分为试验组和对照组各24例。对照... 目的:探讨下肢步行机器辅助训练装置训练对改善脑卒中患者躯干控制和平衡功能的影响。方法:选取2018年10月~2019年11月在中山大学附属第三医院康复科进行康复治疗的脑卒中偏瘫患者48例,并按随机数字表法分为试验组和对照组各24例。对照组接受常规躯干功能训练,每次20min,每周5次,共4周;试验组接受下肢步行机器辅助训练装置训练,每次20min,每周5次,共4周。治疗前后,采用躯干障碍量表(TIS)和Fugl-Meyer平衡评分(FMA-B)分别对2组患者的躯干控制和平衡功能进行评估。结果:治疗后,两组患者的TIS、FMA-B分均较治疗前升高(P<0.01),且试验组治疗后的TIS、FMA-B分均高于对照组(P<0.01)。结论:下肢步行机器辅助训练装置是提高脑卒中偏瘫患者的躯干控制和平衡功能的一个有效的方法。 展开更多
关键词 脑卒中 下肢步行机器 躯干 平衡 躯干障碍量表 Fugl-Meyer平衡评分
文章速递Exergetic Analysis of a Refrigeration System with Mechanical Vapors Compression 认领
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作者 Louis Okotaka Ebale Aristide H. W. Nakavoua Landry Jean Pierre Gomat 《能源与动力工程(英文)》 2020年第8期490-498,共9页
The main purpose of this study is to improve the energy efficiency of a refrigerated facility by means of exergetic analysis. In order to achieve this goal, we have evaluated the input exergy flows of the whole system... The main purpose of this study is to improve the energy efficiency of a refrigerated facility by means of exergetic analysis. In order to achieve this goal, we have evaluated the input exergy flows of the whole system to deduce the exergetic yields, which are compared to the degree of irreversibility in order to have a qualitative measurement of energy losses. The concept of exergy is the part of energy that is virtually converted into work. The exergetic analysis </span><span style="font-size:12px;font-family:Verdana;">was performed on a refrigeration unit ZR22K3E Copeland Scroll. The results of this analysis are consistent with the condition, that the exergetic performance, which is: 36.57% and it is approximately equal to the degree of irreversibility which is 37.50%. This approach provides a comprehensive, standard and rigorous framework for the analysis of energy systems, and thus for </span><span style="font-size:12px;font-family:Verdana;">the understanding and systemic management of the energy challenge. 展开更多
关键词 Exergy Exergetic Balance Exergetic Performance
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文章速递The Experiments Detecting of Real Magnetic Charges in Structures of Atoms and Substance 认领
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作者 Robert A. Sizov 《现代物理(英文)》 2020年第8期1245-1261,共17页
Magnetic neutron scattering in Y-type hexagonal ferrite crystals, studied by the author in 1968-1971 and presented in the article showed that the entire density of the so-called magnetic moments of Fe<span style=&q... Magnetic neutron scattering in Y-type hexagonal ferrite crystals, studied by the author in 1968-1971 and presented in the article showed that the entire density of the so-called magnetic moments of Fe<span style="white-space:nowrap;"><sup>3+</sup></span> ions can significantly shift from the position of their nuclei. As result of these shift the structure in form of the chain magnetic spiral is realized in ferrite lattice. The noted shifts of the “magnetic moments” served as the basis for the author’s assumption that these “moments” are “fig sheets” behind which the magnetic poles (magnetic charges) real existing in the shells of atoms are hidden. In this case, the scattering of neutrons is carried out by magnetic charges, and not theoretical surrogates in the form of magnetic moments. In addition to participating in atomic structures, magnetic charges populate potential conduction zones in conductors, where they are exist in compositions of magnetic dipoles. Under the influence of an external magnetic field, a polarization of magnetic dipoles is realized in the conductor, the field strengths of which are directed against the external magnetic field. It is these dipole magnetic fields that are responsible for such a well-known physical phenomenon as diamagnetism. Under the conditions of noted polarization of magnetic dipoles the author managed to perform mechanical separation of magnetic charges in pairs ±g and to charge experienced bodies (metal plates) by the magnetic charges of one sign. The fact of such a charging was detected through magnetostatic interaction between magnetic charges on the plates using highly sensitive torsion balances. This experiment is presented in detail in this article. The results of these experiments, as well as subsequent experimental and theoretical studies of the author, which, in general composition, were carried out from 1968 to the present, showed that magnetic charges are real structural components of the atoms and substance. So, for example, the atomic shells are not electronic but electromagnetic. The main reason that real magnetic charges were <span style="font-family:Verdana;">“</span><span style="font-family:Verdana;">buried alive” in the existing physical theories is the physics of their confinement in substance forces of which, in its rigidity, is many times greater than the electron confinement forces.</span> 展开更多
关键词 Magnetic Charges Magnetons Antimagnetons True Antielectrons Magnetization Magnetic Structures Torsion Balance The Magnetostatic Interaction
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文章速递Northwest Atlantic Ocean’s SSTs 认领
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作者 Kern E. Kenyon 《自然科学期刊(英文)》 2020年第6期317-319,共3页
<p class="MsoNormal"> <span lang="EN-US" style="" color:black;"=""><span style="font-family:Verdana;">In the southwestern </span>North Atl... <p class="MsoNormal"> <span lang="EN-US" style="" color:black;"=""><span style="font-family:Verdana;">In the southwestern </span>North Atlantic Ocean</span><span style="font-variant-ligatures:normal;font-variant-caps:normal;orphans:2;text-align:start;widows:2;-webkit-text-stroke-width:0px;text-decoration-style:initial;text-decoration-color:initial;word-spacing:0px;">,</span><span style="font-variant-ligatures:normal;font-variant-caps:normal;orphans:2;text-align:start;widows:2;-webkit-text-stroke-width:0px;text-decoration-style:initial;text-decoration-color:initial;word-spacing:0px;"> the area between the 80F isotherm and the </span><span style="font-variant-ligatures:normal;font-variant-caps:normal;orphans:2;text-align:start;widows:2;-webkit-text-stroke-width:0px;text-decoration-style:initial;text-decoration-color:initial;word-spacing:0px;">equator, and between 30W longitude and the western most land boundary, is compiled for each month from a world atlas of sea surface temperatures. Between February and March</span><span style="font-variant-ligatures:normal;font-variant-caps:normal;orphans:2;text-align:start;widows:2;-webkit-text-stroke-width:0px;text-decoration-style:initial;text-decoration-color:initial;word-spacing:0px;">,</span><span style="font-variant-ligatures:normal;font-variant-caps:normal;orphans:2;text-align:start;widows:2;-webkit-text-stroke-width:0px;text-decoration-style:initial;text-decoration-color:initial;word-spacing:0px;"> the area starts to increase from 100 units until a maximum of over 1000 units is reached in August, after which the area decreases. One unit equals one latitude/longitude square. While increasing by swelling to the north, the temperature inside the area essentially does not increase, in spite of the self-evident fact that absorption of solar heat increases the whole time in the top 100 m of the water column. It is proposed that sea level rises by thermal expansion, starting at the equator, producing a northward slope in sea level which in turn drives warm water in the surface layer northward. This proposition is consistent with the heat balance required of the North Atlantic.</span> </p> <span><span><span style="line-height:102%;"></span></span></span> 展开更多
关键词 North Atlantic Heat Balance
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文章速递Simulation and Techno-Economic Performance of a Novel Charge Calculation and Melt Optimization Planning Model for Steel Making 认领
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作者 Onigbajumo Adetunji Saliu Ojo Seidu 《矿物质和材料特性和工程(英文)》 2020年第4期277-300,共24页
Process algorithm, numerical model and techno-economic assessment of charge calculation and furnace bath optimization for target alloy for induction furnace-based steelmaking is presented in this study. The developed ... Process algorithm, numerical model and techno-economic assessment of charge calculation and furnace bath optimization for target alloy for induction furnace-based steelmaking is presented in this study. The developed algorithm combines the make-to-order (MTO) and charge optimization planning (COP) of the steel melting shop in the production of target steel composition. Using a system-level approach, the unit operations involved in the melting process were analyzed with the purpose of initial charge calculation, prevailing alloy charge prediction and optimizing the sequence of melt chemistry modification. The model performance was established using real-time production data from a cast iron-based foundry with a 1- and 2-ton induction furnace capacity and a medium carbon-based foundry with a 10- and 15-ton induction furnace capacity. A simulation engine (CastMELT) was developed in Java IDE with a MySQL database for continuous interaction with changing process parameters to run the model for validation. The comparison between the model prediction and production results was analyzed for charge prediction, melt modification and ferroalloy optimization and possible cost savings. The model performance for elemental charge prediction and calculation purpose with respect to the charge input (at overall scrap meltdown) gave R-squared, Standard Error, Pearson correlation and Significance value of (0.934, 0.06, 0.97, 0.0003) for Carbon prediction, (0.962, 0.06, 0.98, 0.00009) for Silicon prediction, (0.999, 0.048, 0.999, 9E -11) for Manganese Prediction, and (0.997, 0.076, 0.999, 6E -7) for Chromium prediction respectively. Correlation analysis for melt modification (after charging of ferroalloy) using the model for after-alloying spark analysis compared with the target chemistry is at 99.82%. The results validate the suitability of the developed model as a functional system of induction furnace melting for combined charge calculation and melt optimization Techno-economic evaluation results showed that 0.98% - 0.25% ferroalloy saving per ton of melt is possible using the model. This brings about an annual production cost savings of 100,000 $/y in foundry A (medium carbon steel) and 20,000 $/y in foundry B (cast iron) on the use of different ferroalloy materials. 展开更多
关键词 Charge Calculation Process Simulation Modelling Induction Furnace Steel Making Techno-Economics Mass and Energy Balance
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虚拟现实技术对老年人平衡功能康复效果的Meta分析 认领
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作者 梁明 魏珍 +5 位作者 谢荣 徐奕鹏 侯甜 陶静 王宝霞 方瑞 《中国康复理论与实践》 CSCD 北大核心 2020年第3期278-284,共7页
目的系统评价虚拟现实技术对老年人平衡功能康复的有效性。方法从中国知网、万方数据、中国生物医学文献数据库、维普、Web of Science、PubMed、Clinical Science、EMBASE、Science Direct、Medline、Cohrane Library对照实验中心注册... 目的系统评价虚拟现实技术对老年人平衡功能康复的有效性。方法从中国知网、万方数据、中国生物医学文献数据库、维普、Web of Science、PubMed、Clinical Science、EMBASE、Science Direct、Medline、Cohrane Library对照实验中心注册数据库和谷歌学术,检索2009年至2019年虚拟现实平衡康复训练与常规康复训练对照治疗老年人平衡功能障碍的临床随机对照试验,筛选文献、提取资料并评价纳入研究的偏倚风险,运用RevMan软件进行Meta分析。结果最终纳入20项临床随机对照试验。对所有年龄段老年人,Berg平衡量表(BBS)评分有显著性差异(WMD=2.33,95%CI0.88~3.78);对<75岁老年人,BBS评分有显著性差异(WMD=2.59,95%CI0.22~4.97);对>75岁老年人,BBS评分有显著性差异(WMD=2.69,95%CI1.82~3.57)。对所有年龄段老年人,计时起立-行走试验(TUGT)时间有显著性差异(WMD=-0.96,95%CI-1.65~-0.28);对<75岁老年人,TUGT时间有显著性差异(WMD=-1.06,95%CI-1.98~-0.15);对>75岁老年人,TUGT时间无显著性差异(WMD=-0.81,95%CI-1.98~0.37)。结论虚拟现实平衡功能训练能有效促进老年人平衡及步行功能康复。 展开更多
关键词 老年人 平衡 虚拟现实 康复 META分析
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Groundwater net discharge rates estimated from lake level change in Badain Jaran Desert, Northwest China 认领
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作者 Xingfan WANG Hui ZHAO +3 位作者 Yongwei SHENG Jianwei GENG Keqi WANG Hongyu YANG 《中国科学:地球科学英文版》 SCIE EI CAS CSCD 2020年第5期713-725,共13页
Over a hundred sizable lakes,some even larger than~1 km2,are distributed across the lowlands between megadunes in the southeastern Badain Jaran Desert(BJD),northwest China.With rather limited precipitation and hardly ... Over a hundred sizable lakes,some even larger than~1 km2,are distributed across the lowlands between megadunes in the southeastern Badain Jaran Desert(BJD),northwest China.With rather limited precipitation and hardly any surface runoff,these lakes are fed mainly by groundwater.However,the source of the groundwater and the groundwater discharge rates to these lakes are poorly understood.Water level and temperature of four representative lakes in the southeastern BJD were monitored continuously between 2013 and 2017.Water surface evaporation and rainfall in this area were also measured.Combining these acquired data,groundwater discharge rates were estimated using water balance models.The results show that the four lakes have similar recharge and discharge patterns,but at different average net groundwater discharge rates ranging from 1.79 to 3.09 mm d?1.The lake level variation mainly depends on groundwater discharge and lake surface evaporation.We found that diurnal lake level variation may be controlled by earth tide and atmospheric pressure change,and is five times greater than the evaporation.The desert precipitation and deep confined groundwater with high temperature were found also recharging the desert lakes.An Empirical Mode Decomposition(EMD)method was used to identify the lake level trend.All lake levels increased over the last four years,except one decreased in 2015 and 2016.The lake levels’increasing trend is synchronously similar with the precipitation in north China.This study analyzes annual and seasonal lake level variations,and also finds the diurnal water cycle between the groundwater and lake water for the first time. 展开更多
关键词 GROUNDWATER DISCHARGE LAKE level Water BALANCE Badain Jaran DESERT
At what carbon price forest cutting should stop 认领
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作者 Timo Pukkala 《林业研究:英文版》 SCIE CAS CSCD 2020年第3期713-727,共15页
T he carbon sink of boreal forests can be increased by paying forest landowners for carbon sequestration and taxing carbon releases. The aim of the study was to analyze the eff ect of carbon pricing on optimal forest ... T he carbon sink of boreal forests can be increased by paying forest landowners for carbon sequestration and taxing carbon releases. The aim of the study was to analyze the eff ect of carbon pricing on optimal forest management when forests are managed for maximal discounted benefi ts from timber production and carbon payments. A0.5% random sample of all private forest stands of Finland was used in the analyses(48,842 stands). Calculations were performed for a 100-year time horizon. It was assumed that the carbon balance(diff erence between sequestrated carbon and released carbon) in the forest(trees and soil) or the carbon balance of forestry(trees, soil and wood-based products)was subsidized(positive balance) or taxed(negative balance)by 0, 50, 100 or 150 € t-1, corresponding to CO2 prices of 0,13.6, 27.3 or 40.9 € t-1, respectively. The results showed that paying forest landowners 150 € t-1 of carbon sequestrated in forests would lead to the cessation of all cuttings everywhere in Finland for at least 100 years. In the northern part of the country, a carbon price of 100 € t-1 would be enough to make the no-cutting management economically optimal.A low carbon price had the highest relative impact(value ofincreased sequestration divided by the cost of carbon payments). The benefi t/cost ratio of carbon subsidies was higher in the northern part of boreal zone than in the southern parts. Subsidizing within-forest carbon sequestration by 50 € t-1 would increase the carbon sequestration of Finnish forestry by 50%, ranging from 36%(south Finland) to 116%(north Finland). A payment of 100 € t-1 or more would increase carbon sequestration by 70%, which is nearly the maximum possible increase that can be obtained by carbon subsidies. 展开更多
关键词 BOREAL FOREST CARBON balance CARBON SEQUESTRATION CARBON SUBSIDIES Optimal FOREST management
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