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1.
冷连轧机过程控制在线负荷分配方法   总被引:3,自引:0,他引:3  
介绍了一种在线使用的冷连轧机负荷分配方法:通过查询数据库得到初始的负荷分配模式和负荷分配比,利用该负荷分配模式建立单目标负荷目标函数;采用简化的Newton Raphson法迭代求解非线性方程组,得到负荷分配的初始结果;根据第5机架轧制带钢长度对负荷分配结果进行修正,以克服轧制过程中带钢打滑现象;对负荷分配结果进行极限值的检查修正并最终确定负荷分配结果。该负荷分配方法用于在线,有较好的使用效果。  相似文献   

2.
杜涛  蔡九菊 《中国冶金》2006,16(12):38-38
借鉴和应用产品生命周期评价方法分析钢铁生产流程的环境负荷,建立了关于钢铁生产流程环境负荷的基本概念、评价指标和指标体系,通过对两类典型钢铁生产流程环境负荷的对比分析,研究不同生产流程对环境负荷产生的影响,指出降低环境负荷的方向和途径,为钢铁企业优化生产流程、降低环境负荷提供指导和参考。  相似文献   

3.
祝孔林  单旭沂 《钢铁》2007,42(1):45-49
运用KDD技术对热轧带钢生产中过程机大量历史数据和积累了多年的轧制信息(包括轧制负荷相关的信息)进行预处理和数据挖掘,并结合相应的理论知识,开发了适合现场生产的负荷分配模型.该模型能实施多种功能,并在实践中取得成功应用,实现了负荷分配的自动设定,形成了规范的负荷分配制度.同时给出了负荷分配模型的优化方法.  相似文献   

4.
对N100-535/8.83型汽轮机负荷波动的现象进行了研究分析,找到了负荷波动的原因,并提出了相应的解决措施,显著地减少了汽轮机负荷波动情况。  相似文献   

5.
钢铁工业能源节约对环境负荷的影响   总被引:3,自引:0,他引:3  
提出了吨钢环境负荷的源头指标和末端指标,建立了两者之间的关联式,以及吨钢环境负荷v-p分析法和w-p分析法.应用这些方法,分析了1980~1998年近20年间我国钢铁工业吨钢综合能耗和吨钢环境负荷的变化,找出了与国外主要产钢国吨钢环境负荷的差距,指出了进一步降低我国钢铁工业吨钢环境负荷的主要途径和措施.  相似文献   

6.
寇广孝 《工业炉》2004,26(1):44-47
对钢瓶热载体烤漆炉热负荷的影响因素进行了分析探讨,初步提出了其热负荷计算公式。通过计算实例,说明了影响烤漆炉热负荷的主要因素。  相似文献   

7.
赵新民 《山西冶金》2010,33(6):21-23
介绍了太钢5号高炉近期的炉体热负荷分布状况,合理的炉体热负荷分布对高炉生产的重要性。并分析影响热负荷的因素关系,提出高炉热负荷的合理范围和控制方法。  相似文献   

8.
提出了一种根据钢铁企业典型工序综合负荷特性,在充分考虑外部影响因素的情况下,合理选择不同工序负荷的预测模型及方法,从而实现对工序分量的负荷预测;并采用组合预测的方法将工序分量加权累加后,生成企业关口负荷预测结果。该预测方法综合考虑了企业各个工序的负荷特性和负荷变化趋势,有效提高企业关口负荷预测的精度,与企业用电负荷管理与电力需量控制系统相结合,可有效降低企业生产的供电成本。  相似文献   

9.
本文叙述了计算机负荷测试的目的及方法,对热轧轧线过程机的负荷进行了剖析,提出了降低负荷率的软件上的方法,对于生产过程控制机的负荷分析及降低负荷有一定的益处,  相似文献   

10.
在对电力系统电长期、中期、短期(超短期)负荷预测基本方法的特点和适用条件范围进行分析后。详细介绍了负荷密度法在城市电网中短期负荷预测中的优势。最后结合一中型城市城市电网2008—2010年的电力负荷实际特征数据。对该城市电网2011—2017年7年内的近期电力负荷数据进行了预测,并与该地区国民经济发展所需电力增长速率相比,证明了负荷密度法所预测的电力负荷数据的准确性,再次验证了负荷密度法在电力负荷预测中的可行性、可靠性和精确性。  相似文献   

11.
Predictions from perceptual load theory (Lavie, 1995, 2005) regarding object recognition across the same or different viewpoints were tested. Results showed that high perceptual load reduces distracter recognition levels despite always presenting distracter objects from the same view. They also showed that the levels of distracter recognition were unaffected by a change in the distracter object view under conditions of low perceptual load. These results were found both with repetition priming measures of distracter recognition and with performance on a surprise recognition memory test. The results support load theory proposals that distracter recognition critically depends on the level of perceptual load. The implications for the role of attention in object recognition theories are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
This study investigates the impact of working memory (WM) load on response conflicts arising from spatial (non) correspondence between irrelevant stimulus location and response location (Simon effect). The dominant view attributes the Simon effect to automatic processes of location-based response priming. The automaticity view predicts insensitivity of the Simon effect to manipulations of processing load. Four experiments investigated the role of spatial and verbal WM in horizontal and vertical Simon tasks by using a dual-task approach. Participants maintained different amounts of spatial or verbal information in WM while performing a horizontal or vertical Simon task. Results showed that high load generally decreased, and sometimes eliminated, the Simon effect. It is interesting to note that spatial load had a larger impact than verbal load on the horizontal Simon effect, whereas verbal load had a larger impact than spatial load on the vertical Simon effect. The results highlight the role of WM as the perception-action interface in choice-response tasks. Moreover, the results suggest spatial coding of horizontal stimulus-response (S-R) tasks, and verbal coding of vertical S-R tasks. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

13.
OBJECTIVES: To study the role of HIV-1 biological phenotype, viral load and neutralizing antibodies in male-to-female heterosexual transmission of HIV-1. METHODS: Seven transmitting and seven non-transmitting HIV-1-seropositive heterosexual male index cases were included in the present study. All couples had engaged in unprotected sex for a period of over 1 year. Transmission was defined by the seroconversion of the female sexual partner. Virus isolates were tested in MT-2 cells for replication and syncytia induction. HIV-1 RNA plasma load was measured by the branched DNA technique. Serum neutralizing activity to primary HIV-1 isolates was tested by using peripheral blood mononuclear cells (PBMC) as target cells. RESULTS: Non-transmitting index cases had a lower HIV-1 RNA concentration in plasma than transmitting index cases. Non-transmitting index cases also tended to have serum neutralizing activity with broad specificity and to have viruses with low replicative capacity, as characterized by 50% infectious dose titres in PBMC and by the lack of MT-2 tropism. CONCLUSIONS: The results indicate that plasma viral-RNA load is a marker for transmission. Moreover, an interplay between the host immune response and viral replication may modulate the level of viral load and thereby influence HIV-1 transmission.  相似文献   

14.
The conventional analysis and design of highway bridges ignore the contribution of sidewalks and∕or railings in a bridge deck when calculating the flexural strength of superstructures. The presence of sidewalks and railings or parapets acting integrally with the bridge deck have the effect of stiffening the outside girders and attracting more load while reducing the load effects in the interior girders. This paper presents the results of a parametric study showing the influence of typical sidewalks and railings on wheel load distribution as well as on the load-carrying capacity of highway bridges. A typical one-span, two-lane, simply supported, composite steel girder bridge was selected in order to investigate the influence of various parameters such as: span length, girder spacing, sidewalks, and railings. A total of 120 bridges were analyzed using three-dimensional finite-element analysis. American Association of State Highway and Transportation Officials (AASHTO) HS20 design trucks were positioned in both lanes to produce the maximum moments. The finite-element analysis results were also compared with AASHTO wheel load distribution factors. The AASHTO load and resistance factor design (LRFD) wheel load distribution formula correlated conservatively with the finite-element results and all were less than the typical empirical formula (S∕5.5). The presence of sidewalks and railings were shown to increase the load-carrying capacity by as much as 30% if they were included in the strength evaluation of highway bridges.  相似文献   

15.
Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target motion discrimination was significantly impaired, a result attributed to the carry-over of distractor inhibition. Increasing the difficulty of cue detection increased the motion target impairment, as distractor inhibition is thought to increase under demanding (high load) conditions in order to maximize selection efficiency. The apparent conflict with studies reporting reduced distractor inhibition under high load conditions was resolved by distinguishing between the effects of "cognitive" and "perceptual" load. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

16.
分析并计算了集卷站升降机构传动链轮的动载荷 ,找出轮齿断裂的主要原因是动载荷太大。与动载荷有关的三个因素是转速、节距和齿数 ,改变转速和节距需要较多的资金 ,而增加齿数则是简单有效的方法 ,即增加一组传动链轮就可以将链条所承受的冲击载荷分配到较多的轮齿上 ,从而很好地解决了链轮承受冲击载荷能力不足的问题。  相似文献   

17.
Cyclic creep and stress rupture results are reported and discussed as a function of the lower applied load for INCONEL MA6000, which is a mechanically alloyed oxide dispersion strengthened (ODS) and γ’ precipitation strengthened nickel-base superalloy. In prior work, very large decreases in the effective minimum cyclic creep rate, based on time at maximum load, were found to occur for cyclic creep testing using a lower load near zero. The present results show that this decrease in creep rate depends on the value of the lower load. As the lower load increases, the cyclic creep rate increases proportionally, but remains less than the corresponding static creep rate. The values of the cyclic creep rates are shown to be related to the magnitude of the anelastic strain recovery occurring during the lower load portion of the cyclic creep test. The results are also used to improve on the anelastic relaxation model for cyclic creep of materials with strong pinning points.  相似文献   

18.
The discrepancy between traditional (force scaling models) and the more recently conceived dynamic explanations of load compensation (lambda model) was the departure point for the present study. By using the complex "open" motor skill of catching a ball--rather than the traditional "closed" skills--under "normal" (baseline) conditions and under conditions where a spring load was applied to the catching hand (thereby changing the dynamics of the skeletomuscular system) it was hoped to provide further clarification of this issue. Traditional force scaling models, in this respect, would predict that maximal closing velocity of the grasp action, and movement time would not be significantly different between a control and a spring-load condition. In contrast, a dynamic system perspective would maintain that spring loading would be compensated for by a change in the rate of shift of the reciprocal command (R-command). The obtained results showed a significant difference for conditions with regard to the maximal closing velocity of the grasp action, the baseline condition being higher than the two spring-load conditions. Furthermore, a significant difference was found for the aperture at moment of catch, the aperture at moment of catch being smaller in the baseline condition than that under the two spring-load conditions. With regard to the temporal variables, no significant differences were obtained. A comprehensive overall explanation of the obtained data in terms of the force scaling models was not realisable. It may be that findings supporting such theories are task specific and that for constrained tasks--such as catching a ball--different underlying organisational principles apply. The lambda model, however, could explain adequately the obtained results. It was concluded that, except for the preparatory phase associated with load compensation before the onset of the movement of the ball, the spatiotemporal structure of the control pattern underlying catching remains the same (invariant) in both baseline and load conditions. Thereby, the spatiotemporal structure of the resulting movement changes under the influence of the load and thus is not the same for load and baseline condition.  相似文献   

19.
Cyclic creep and stress rupture results are reported and discussed as a function of the lower applied load for INCONEL MA6000, which is a mechanically alloyed oxide dispersion strengthened (ODS) and γ’ precipitation strengthened nickel-base superalloy. In prior work, very large decreases in the effective minimum cyclic creep rate, based on time at maximum load, were found to occur for cyclic creep testing using a lower load near zero. The present results show that this decrease in creep rate depends on the value of the lower load. As the lower load increases, the cyclic creep rate increases proportionally, but remains less than the corresponding static creep rate. The values of the cyclic creep rates are shown to be related to the magnitude of the anelastic strain recovery occurring during the lower load portion of the cyclic creep test. The results are also used to improve on the anelastic relaxation model for cyclic creep of materials with strong pinning points. INCONEL is a trademark of the INCO family of companies formerly Associate Research Scientist with Columbia University  相似文献   

20.
The purpose of this study was to determine whether a patellar ligament-bearing cast reduces the load applied to a foot in a cast. In a study of ten people who had no history of gait abnormalities, disease involving the motor system, or deformities of the lower extremities, we compared the load applied to the plantar aspect of a foot in a cast (as detected with F-Scan computer-monitored pedobarographic sensors) with the total load that an extremity in a cast receives relative to the ground (as detected with force-plates). Six trials were completed three times by each person. The trials consisted of walking (1) while wearing regular shoes; (2) with a patellar ligament-bearing cast on one leg; (3) with a patellar ligament-bearing cast and an overlying soft knee brace, locked in full extension, on the leg; (4) with only a below-the-knee cast on the leg; (5) with a below-the-knee cast and an overlying knee brace, locked in full extension, on the leg; and (6) with only a knee brace, locked in full extension, on the leg. The loads at peak heel-strike for all three trials were averaged and normalized to body weight. The load on the plantar aspect of the foot, as compared with the total load, was reduced a mean of 11 percent when the patellar ligament-bearing cast was worn alone, and it was reduced a mean of 26 percent when the patellar ligament-bearing cast was used with an overlying knee brace locked in full extension. This difference was significant (p = 0.007). With the numbers available, we could not detect a significant difference between the reduction in load when a patellar ligament-bearing cast was worn alone compared with that when a below-the-knee cast was worn alone or between the reduction when a below-the-knee cast was worn alone compared with that when a below-the-knee cast was used with a knee brace (p = 0.3). In conclusion, we could not demonstrate a significant reduction in the load on the foot when a patellar ligament-bearing cast was used in a traditional fashion; however, a significant (p = 0.007) reduction in load was found when a knee brace locked in full extension was worn in addition to the patellar ligament-bearing cast.  相似文献   

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