介绍了非接触式旋转高频链变压器(Contactless Rotary high Frequency Link Transformer,简称CRFT)在旋转机构电源上的应用,CRFT的使用代替了传统的电能传递方式,即电刷电能传递方式,大大延长了旋转机构电源系统的使用寿命和使用可靠性...介绍了非接触式旋转高频链变压器(Contactless Rotary high Frequency Link Transformer,简称CRFT)在旋转机构电源上的应用,CRFT的使用代替了传统的电能传递方式,即电刷电能传递方式,大大延长了旋转机构电源系统的使用寿命和使用可靠性。采用软开关技术,减少了电能在磁场中传递而进行变换产生的电磁干扰,解决了与静止供电完全没有物理接触的旋转电路的供电问题。实验证明,CRFT完全可以在旋转机构供电场合代替电刷及滑环。展开更多
To eliminate rotation deviation of sequential images mosaic when measuring linear dimensions of large scale parts with computer vision, a novel algorithm based on the chain code searching method is proposed. After ima...To eliminate rotation deviation of sequential images mosaic when measuring linear dimensions of large scale parts with computer vision, a novel algorithm based on the chain code searching method is proposed. After image preprocessing, including image filtering, image segmentation, and edge detection, the chain code length of the contour line can be searched out by the proposed method. Then, the angle from the contour line to the coordinate axis is computed with the length of the contour line. After that, the sequence is rotated in the opposite direction and the rotation deviation is eliminated. It is prepared for the next mosaic of sequences in eliminating shifting deviation. Experiments are carried out on parts with a linear profile rotating angle from 0° to 9°. The results show that compared with the commonly used Hough transform, the new method has higher precision and faster speed, which is important in realizing online high precision measurements of large scale parts with a linear profile.展开更多
As a demonstration of the spectrum-parity matching condition （SPMC） for quantum state transfer, we investigate the propagation of single-magnon state in the Heisenberg chain in the confined external tangent magnetic...As a demonstration of the spectrum-parity matching condition （SPMC） for quantum state transfer, we investigate the propagation of single-magnon state in the Heisenberg chain in the confined external tangent magnetic field analytically and numerically. It shows that the initial Gaussian wave packet can be retrieved at the counterpart location near-perfectly over a longer distance if the dispersion relation of the system meets the SPMC approximately.展开更多
The links of Motoman HP6 arc welding robot are considered as an open kinematic chain which consists of a series of rotational joints through concatenation. One end of the open chain is fixed to the base or the earth, ...The links of Motoman HP6 arc welding robot are considered as an open kinematic chain which consists of a series of rotational joints through concatenation. One end of the open chain is fixed to the base or the earth, and the other end which is free fastens the end executor to complete various duties. Each link of this arc welding robot has four kinds of Denavit-Hartenberg parameters: common normal length between two adjacent links, angle of two adjacent joints, distance between the crossing of common normal length and two joints axes, and angle of two adjacent links. The displacement relation between each link of the Motoman HP6 arc welding robot is introduced, and the kinematic positive-going solution and the kinematic passive-going solution are calculated.展开更多
AIM:To compare ghrelin levels in plasma and gastric mucosa before and after Helicobacter pylori(H.pylori) treatment in children with H.pylori-associated functional dyspepsia.METHODS:Children with H.pylori-associated f...AIM:To compare ghrelin levels in plasma and gastric mucosa before and after Helicobacter pylori(H.pylori) treatment in children with H.pylori-associated functional dyspepsia.METHODS:Children with H.pylori-associated functional dyspepsia were enrolled in this study.H.pylori infection was confirmed by positive bacterial culture results.All of the children received triple H.pylori eradication therapy(a 2 wk course of omeprazole,amoxicillin,and clarithromycin).The children were divided into two groups based on the success of the H.pylori treatment:group 1(eradicated)-patients who had a negative 13C-urea breath test 2 mo after the end of therapy;and group 2(non-eradicated)-patients who had a positive 13C-urea breath test.Plasma ghrelin,gastric ghrelin mRNA,and the body mass index were evaluated in both groups before and after the H.pylori treatment.The plasma ghrelin levels were measured by a radioimmunoassay.The expression of gastric ghrelin mRNA was determined by real-time reverse transcription polymerase chain reaction.RESULTS:A total of 50 children with H.pylori-associated functional dyspepsia were treated with triple H.pylori eradication therapy.The mean age of the children was 5.52 ± 0.83 years,and there were 28 males and 22 females.Among the 50 H.pylori-positive children,30 successfully achieved eradication,and 20 did not.The mean plasma ghrelin levels of group 1 were 22.17 ± 1.73 ng/L and 26.59 ± 2.05 ng/L before and after the treatment,respectively,which was a significant increase(P = 0.001).However,the mean plasma ghrelin level of group 2 before and after the H.pylori treatment was 21.34 ± 2.40 ng/L and 22.24 ± 2.10 ng/L(P = 0.785).The plasma ghrelin levels increased substantially after treatment in group 1 but showed only minor changes in group 2.Similarly,the gastric ghrelin mRNA expression in group 1 before treatment was 2.84 ± 0.08.After treatment,the level was 3.11 ± 0.65,which was significantly different(P = 0.023).The gastric ghrelin mRNA expression in group 2 did not change significantly during the treatment(2.82 ± 0.44 vs 2.79 ± 0.31,P = 0.875).The plasma ghrelin and gastric ghrelin mRNA levels in group 1 increased substantially after the treatment but did not do so in group 2.In addition,the body mass index the two groups did not differ significantly 2 mo before and after the H.pylori treatment.CONCLUSION:H.pylori eradication increases the plasma and tissue ghrelin levels in children with H.pylori-associated functional dyspepsia.展开更多
This paper provides an improved understanding of the movement mechanisms of both bed-rock gully and sandy soil gully when underground mining occurs underneath,followed by systematic analysis of the contributing factor...This paper provides an improved understanding of the movement mechanisms of both bed-rock gully and sandy soil gully when underground mining occurs underneath,followed by systematic analysis of the contributing factors such as mining advance direction,gully slope angle,gully erosion coefficient and mining height.This paper presents the results from monitoring,theoretical analyses and up to date modeling based on the geological features in the gully affected area,and the implications of these results to the success of roof support trial.It was observed that when mining occurred towards the gully,sliding of slope block along the fracture surface occurred,which resulted in unstable roof condition;when mining progressed away from the gully,polygon blocks developed in the gully slope and rotated in reversed direction forming hinged structure;within the bed-rock slope,the hinged structure was unstable due to shear failure of the polygon block;however,within the sandy soil slope,the structure was relatively stable due to the gradual rotating and subsiding of the polygon block.The increase of the value of slope angle and mining height lead to a faster and more intensive fracture development within the gully slope,which had a pronounced effect on gully slope stability and underground pressure.Various remediation approaches are hence proposed in this paper including introducing more powerful support and reasonable mining height,setting up working face along or away from gullies,using room and pillar,strip mining and backfill instead of longwall mining.展开更多
The recent thermodynamical interpretation of the field equations of gravity is revisited and extended to the killing horizons linked to the rotation （Kerr black holes）. An entropic force can be defined also for thes...The recent thermodynamical interpretation of the field equations of gravity is revisited and extended to the killing horizons linked to the rotation （Kerr black holes）. An entropic force can be defined also for these horizons which are not event horizons but show thermodynamical features that in previous works were used to explain the rotational properties of Kerr solutions. Such entropic force is needed to describe the energetic processes, which do not change the usual thermal entropy of the rotating black hole （reversible transformations, superradiance）.展开更多
文摘介绍了非接触式旋转高频链变压器(Contactless Rotary high Frequency Link Transformer,简称CRFT)在旋转机构电源上的应用,CRFT的使用代替了传统的电能传递方式,即电刷电能传递方式,大大延长了旋转机构电源系统的使用寿命和使用可靠性。采用软开关技术,减少了电能在磁场中传递而进行变换产生的电磁干扰,解决了与静止供电完全没有物理接触的旋转电路的供电问题。实验证明,CRFT完全可以在旋转机构供电场合代替电刷及滑环。
基金The National Natural Science Foundation of China(No.50805023)the Program for Special Talent in Six Fields of Jiangsu Province(No.2008144)Jiangsu Provincial Science and Technology Achievement Transformation Project(No.BA2010093)
文摘To eliminate rotation deviation of sequential images mosaic when measuring linear dimensions of large scale parts with computer vision, a novel algorithm based on the chain code searching method is proposed. After image preprocessing, including image filtering, image segmentation, and edge detection, the chain code length of the contour line can be searched out by the proposed method. Then, the angle from the contour line to the coordinate axis is computed with the length of the contour line. After that, the sequence is rotated in the opposite direction and the rotation deviation is eliminated. It is prepared for the next mosaic of sequences in eliminating shifting deviation. Experiments are carried out on parts with a linear profile rotating angle from 0° to 9°. The results show that compared with the commonly used Hough transform, the new method has higher precision and faster speed, which is important in realizing online high precision measurements of large scale parts with a linear profile.
基金The project supported by National Natural Science Foundation of China under Grant No. 10474104 and the National Fundamental Research Program of China under Grant No. 2001CB309310
文摘As a demonstration of the spectrum-parity matching condition （SPMC） for quantum state transfer, we investigate the propagation of single-magnon state in the Heisenberg chain in the confined external tangent magnetic field analytically and numerically. It shows that the initial Gaussian wave packet can be retrieved at the counterpart location near-perfectly over a longer distance if the dispersion relation of the system meets the SPMC approximately.
文摘The links of Motoman HP6 arc welding robot are considered as an open kinematic chain which consists of a series of rotational joints through concatenation. One end of the open chain is fixed to the base or the earth, and the other end which is free fastens the end executor to complete various duties. Each link of this arc welding robot has four kinds of Denavit-Hartenberg parameters: common normal length between two adjacent links, angle of two adjacent joints, distance between the crossing of common normal length and two joints axes, and angle of two adjacent links. The displacement relation between each link of the Motoman HP6 arc welding robot is introduced, and the kinematic positive-going solution and the kinematic passive-going solution are calculated.
基金Supported by Nutrition and Development Center in Shanghai Children’s Medical Center
文摘AIM:To compare ghrelin levels in plasma and gastric mucosa before and after Helicobacter pylori(H.pylori) treatment in children with H.pylori-associated functional dyspepsia.METHODS:Children with H.pylori-associated functional dyspepsia were enrolled in this study.H.pylori infection was confirmed by positive bacterial culture results.All of the children received triple H.pylori eradication therapy(a 2 wk course of omeprazole,amoxicillin,and clarithromycin).The children were divided into two groups based on the success of the H.pylori treatment:group 1(eradicated)-patients who had a negative 13C-urea breath test 2 mo after the end of therapy;and group 2(non-eradicated)-patients who had a positive 13C-urea breath test.Plasma ghrelin,gastric ghrelin mRNA,and the body mass index were evaluated in both groups before and after the H.pylori treatment.The plasma ghrelin levels were measured by a radioimmunoassay.The expression of gastric ghrelin mRNA was determined by real-time reverse transcription polymerase chain reaction.RESULTS:A total of 50 children with H.pylori-associated functional dyspepsia were treated with triple H.pylori eradication therapy.The mean age of the children was 5.52 ± 0.83 years,and there were 28 males and 22 females.Among the 50 H.pylori-positive children,30 successfully achieved eradication,and 20 did not.The mean plasma ghrelin levels of group 1 were 22.17 ± 1.73 ng/L and 26.59 ± 2.05 ng/L before and after the treatment,respectively,which was a significant increase(P = 0.001).However,the mean plasma ghrelin level of group 2 before and after the H.pylori treatment was 21.34 ± 2.40 ng/L and 22.24 ± 2.10 ng/L(P = 0.785).The plasma ghrelin levels increased substantially after treatment in group 1 but showed only minor changes in group 2.Similarly,the gastric ghrelin mRNA expression in group 1 before treatment was 2.84 ± 0.08.After treatment,the level was 3.11 ± 0.65,which was significantly different(P = 0.023).The gastric ghrelin mRNA expression in group 2 did not change significantly during the treatment(2.82 ± 0.44 vs 2.79 ± 0.31,P = 0.875).The plasma ghrelin and gastric ghrelin mRNA levels in group 1 increased substantially after the treatment but did not do so in group 2.In addition,the body mass index the two groups did not differ significantly 2 mo before and after the H.pylori treatment.CONCLUSION:H.pylori eradication increases the plasma and tissue ghrelin levels in children with H.pylori-associated functional dyspepsia.
基金provided by the National Natural Science Foundation of China (Grant No.51004101,No.51264035)the Science Foundation for Young Scholars of China University of Mining &Technology (Grant No.2009A001)+1 种基金the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the Fundamental Research Funds for the Central Universities (2012QNA35)
文摘This paper provides an improved understanding of the movement mechanisms of both bed-rock gully and sandy soil gully when underground mining occurs underneath,followed by systematic analysis of the contributing factors such as mining advance direction,gully slope angle,gully erosion coefficient and mining height.This paper presents the results from monitoring,theoretical analyses and up to date modeling based on the geological features in the gully affected area,and the implications of these results to the success of roof support trial.It was observed that when mining occurred towards the gully,sliding of slope block along the fracture surface occurred,which resulted in unstable roof condition;when mining progressed away from the gully,polygon blocks developed in the gully slope and rotated in reversed direction forming hinged structure;within the bed-rock slope,the hinged structure was unstable due to shear failure of the polygon block;however,within the sandy soil slope,the structure was relatively stable due to the gradual rotating and subsiding of the polygon block.The increase of the value of slope angle and mining height lead to a faster and more intensive fracture development within the gully slope,which had a pronounced effect on gully slope stability and underground pressure.Various remediation approaches are hence proposed in this paper including introducing more powerful support and reasonable mining height,setting up working face along or away from gullies,using room and pillar,strip mining and backfill instead of longwall mining.
文摘The recent thermodynamical interpretation of the field equations of gravity is revisited and extended to the killing horizons linked to the rotation （Kerr black holes）. An entropic force can be defined also for these horizons which are not event horizons but show thermodynamical features that in previous works were used to explain the rotational properties of Kerr solutions. Such entropic force is needed to describe the energetic processes, which do not change the usual thermal entropy of the rotating black hole （reversible transformations, superradiance）.
