An automatic surface quality inspection system installed on a finishing lineof cold rolled strips is introduced. The system is able to detect surface defects on cold rolledstrips, such as scratches, coil breaks, rusts...An automatic surface quality inspection system installed on a finishing lineof cold rolled strips is introduced. The system is able to detect surface defects on cold rolledstrips, such as scratches, coil breaks, rusts, roll imprints, and so on. Multiple CCD area scancameras were equipped to capture images of strip surface simultaneously. Defects were detectedthrough 'Dark-field illumination' which is generated by LED illuminators. Parallel computationtechnique and fast processing algorithms were developed for real-time data processing. Theapplication to the production line shows that the system is able to detect defects effectively.展开更多
In China＇s unremitting efforts to fight against desertification, Elion Resources Group, a private enterprise in north China＇s Inner Mongolia Autonomous Region, is playing an exemplary role. Wang Wenbiao, Chairman of...In China＇s unremitting efforts to fight against desertification, Elion Resources Group, a private enterprise in north China＇s Inner Mongolia Autonomous Region, is playing an exemplary role. Wang Wenbiao, Chairman of the company, received the Champions of the Earth Award from the United Nations Environment Program （UNEP） in 2017 for his contributions over the past few decades. The following is an edited excerpt of a profile of Wang by Xinhua News Agency.展开更多
Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists re...Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists regarding which of these finishing lines will leave the most amount of residual dentine coronally on maxillary lateral incisors and mandibular incisors. Objective: To assess the coronal residual dentine thickness after different cervical finishing lines for anterior crown preparations. Materials and Methods: A prospective comparative study was conducted including mandibular incisors and maxillary laterals that were taken from subjects from 18 to 30 years old. Teeth in each of the three groups were randomly separated into three cervical margin preparation groups: knife edge, chamfer and shoulder. The teeth were then prepared for single crown coverage using these finishing lines. The teeth were sectioned halfway through the crown preparation, and a digital caliper was used to determine the residual dentine thickness at the buccal, lingual, mesial and distal areas. The Tukey test was used for mean comparison, and ANOVA analysis was used to evaluate the variation in mean residual dentine thickness. Results: For upper lateral incisors, knife edge finishing lines showed the highest amount of remaining dentine thickness—1.5 mm. lingually, while the upper lateral incisors mesially had the least amount of 0.53 mm for shoulder finishing lines. The least residual dentine (0.53 mm for the shoulder and 0.70 mm for the chamfer finishing line) was found in the interproximal portions of all the teeth that were selected. Lower central incisors had the least amount of residual dentine 0.61 mm for shoulder preparations mesially whiles lower lateral incisors had the least amount of residual dentine for shoulder preparations 0.58 mm distally. There was a statistically significant difference of 0.001 across the groups. Conclusion: The thickness of residual dentine seen coronally after the three finishing line preparations showed a statistically significant difference and the knife edge finishing line provided enough coronal protection within the scope of this study.展开更多
目的:研究不同粘结剂和不同边缘设计对冠边缘微渗漏的影响,以指导临床设计、操作,为临床减少微渗漏提供依据。方法:选取45颗离体牙,按不同肩台形式随机分为凹形肩台组、直角肩台组和斜面形肩台组。制作金属冠。每种肩台分别用3种粘结剂...目的:研究不同粘结剂和不同边缘设计对冠边缘微渗漏的影响,以指导临床设计、操作,为临床减少微渗漏提供依据。方法:选取45颗离体牙,按不同肩台形式随机分为凹形肩台组、直角肩台组和斜面形肩台组。制作金属冠。每种肩台分别用3种粘结剂粘固,分别为Rely X Unicem树脂组、3M树脂改良型玻璃离子组和聚羧酸组。经冷热循环实验后氨化硝酸银染色,显影。沿牙体长轴切开,光学显微镜下观察冠修复体剖面染料渗透情况,并进行分级评估,对各组微渗漏程度进行统计分析。结果:相同肩台组中,树脂组微渗漏最少,聚羧酸组微渗漏最大(P<0.05);相同粘结剂组中,凹形肩台组与斜面形肩台组微渗漏无明显差别(P>0.05),均少于直角肩台组(P<0.05)。结论:树脂类粘结剂抗微渗漏性能优于玻璃离子类及聚羧酸类粘结剂,是全冠粘结的首选材料;凹形和斜面形肩台是减少微渗漏的理想肩台形式。展开更多
基金This work was financed by the National Natural Science Foundation of China (No.50074010) "863 Program" of China (No. 2001AA339030).]
文摘An automatic surface quality inspection system installed on a finishing lineof cold rolled strips is introduced. The system is able to detect surface defects on cold rolledstrips, such as scratches, coil breaks, rusts, roll imprints, and so on. Multiple CCD area scancameras were equipped to capture images of strip surface simultaneously. Defects were detectedthrough 'Dark-field illumination' which is generated by LED illuminators. Parallel computationtechnique and fast processing algorithms were developed for real-time data processing. Theapplication to the production line shows that the system is able to detect defects effectively.
文摘In China＇s unremitting efforts to fight against desertification, Elion Resources Group, a private enterprise in north China＇s Inner Mongolia Autonomous Region, is playing an exemplary role. Wang Wenbiao, Chairman of the company, received the Champions of the Earth Award from the United Nations Environment Program （UNEP） in 2017 for his contributions over the past few decades. The following is an edited excerpt of a profile of Wang by Xinhua News Agency.
文摘Background: Knife edge, chamfer, and shoulder are the three distinct finishing lines utilized in crown preparations. Each finishing line has relative benefits and drawbacks. However, not much scientific data exists regarding which of these finishing lines will leave the most amount of residual dentine coronally on maxillary lateral incisors and mandibular incisors. Objective: To assess the coronal residual dentine thickness after different cervical finishing lines for anterior crown preparations. Materials and Methods: A prospective comparative study was conducted including mandibular incisors and maxillary laterals that were taken from subjects from 18 to 30 years old. Teeth in each of the three groups were randomly separated into three cervical margin preparation groups: knife edge, chamfer and shoulder. The teeth were then prepared for single crown coverage using these finishing lines. The teeth were sectioned halfway through the crown preparation, and a digital caliper was used to determine the residual dentine thickness at the buccal, lingual, mesial and distal areas. The Tukey test was used for mean comparison, and ANOVA analysis was used to evaluate the variation in mean residual dentine thickness. Results: For upper lateral incisors, knife edge finishing lines showed the highest amount of remaining dentine thickness—1.5 mm. lingually, while the upper lateral incisors mesially had the least amount of 0.53 mm for shoulder finishing lines. The least residual dentine (0.53 mm for the shoulder and 0.70 mm for the chamfer finishing line) was found in the interproximal portions of all the teeth that were selected. Lower central incisors had the least amount of residual dentine 0.61 mm for shoulder preparations mesially whiles lower lateral incisors had the least amount of residual dentine for shoulder preparations 0.58 mm distally. There was a statistically significant difference of 0.001 across the groups. Conclusion: The thickness of residual dentine seen coronally after the three finishing line preparations showed a statistically significant difference and the knife edge finishing line provided enough coronal protection within the scope of this study.
文摘目的:研究不同粘结剂和不同边缘设计对冠边缘微渗漏的影响,以指导临床设计、操作,为临床减少微渗漏提供依据。方法:选取45颗离体牙,按不同肩台形式随机分为凹形肩台组、直角肩台组和斜面形肩台组。制作金属冠。每种肩台分别用3种粘结剂粘固,分别为Rely X Unicem树脂组、3M树脂改良型玻璃离子组和聚羧酸组。经冷热循环实验后氨化硝酸银染色,显影。沿牙体长轴切开,光学显微镜下观察冠修复体剖面染料渗透情况,并进行分级评估,对各组微渗漏程度进行统计分析。结果:相同肩台组中,树脂组微渗漏最少,聚羧酸组微渗漏最大(P<0.05);相同粘结剂组中,凹形肩台组与斜面形肩台组微渗漏无明显差别(P>0.05),均少于直角肩台组(P<0.05)。结论:树脂类粘结剂抗微渗漏性能优于玻璃离子类及聚羧酸类粘结剂,是全冠粘结的首选材料;凹形和斜面形肩台是减少微渗漏的理想肩台形式。
