In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave th...In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave threat to the power grid security.The cause of the accident and the accident process were studied for the sake of further understanding of the impact of lightning on power grid.As an example,110 kV double circuit transmission line(Xilong-line) was analyzed.At first,the system topology was given.Through the analysis on relay protection actions and the fault recorder data,over voltage on the insulator strings was calculated.Based on the analysis and the calculation,accident cause and the process were presented respectively.Secondly,it comes to the conclusion that the lightning failure was caused by counterattack.The wave of the lightning over voltage would spread to the not grounded neutral point of the transformers,and make the neutral protective gap breakdown,then cause freewheeling with the frequency of 50 Hz.As results of the relay protection,the double circuit transmission line all tripped out.Finally,the causes of the accident were proposed that included terrain features,large corner towers,strong thunderstorm weather and poor grounded contact of the tower.展开更多
AIM:To evaluate the efficacy of same-day bowel preparation with Senna alkaloids combined with bisacodyl tablets in routine colonoscopy procedures.METHODS:Between March and June 2013,a sameday bowel preparation was imp...AIM:To evaluate the efficacy of same-day bowel preparation with Senna alkaloids combined with bisacodyl tablets in routine colonoscopy procedures.METHODS:Between March and June 2013,a sameday bowel preparation was implemented in our endoscopy unit.The preparation consisted of a semi-liquid,fiber-free diet one day prior to the procedure,with two bisacodyl tablets after lunch and dinner,and 250 mL of Senna alkaloid with 1.5 L of drinking water at 6 am the day of the procedure.The quality control parameters of colonoscopy were evaluated and implemented according to the guidelines of the American Society for Gastrointestinal Endoscopy.The pre-procedure,duringprocedure and post-procedure patient data were collected and analyzed:(1) pre-procedure(age,gender,comorbid diseases,colonoscopy indications,complete lack of compliance with the bowel preparation protocol);(2) during-procedure(sedation dose,duration of colonoscopy,withdrawal time,cecal intubation rate,polyp detection rate,Boston Bowel Preparation Scores and presence of foam and clear liquid); and(3) postprocedure(visual analogue scale score,pain during the procedure,patient satisfaction and premature withdrawal due to the insufficient bowel preparation).RESULTS:A total of 75 patients were included in this study with a mean age of 54.64 ± 13.29 years; 53.3%(40/75) were female and 46.7%(35/75) were male.A complete lack of compliance with the bowel preparation protocol was seen in 6.7% of patients(5/75).The mean total duration of colonoscopy was 16.12 ± 6.51 min,and the mean withdrawal time was 8.89 ± 4.07 min.The cecal intubation rate was 93.8%(61/64) and the polyp detection rate was 40%(30/75).The mean Boston Bowel Preparation Score was 7.38 ± 1.81,with the following distribution:right colon,2.34 ± 0.89; transverse colon,2.52 ± 0.67; left colon,2.52 ± 0.63.The mean visual analogue scale score was 4.59 ± 1.57.Due to insufficient bowel preparation,seven patients(7/75; 9.3%) were asked to repeat the procedure.Of these,five patients had poor or modest compliance with the protocol,and two patients reported constipation.Premature withdrawal due to insufficient bowel preparation was 2.7%(2/75).The overall satisfaction with the protocol was 86.7%(65/75),with patients reporting they would prefer the same protocol in a repeat procedure.CONCLUSION:The same-day administration of Senna alkaloids appears to be a safe and effective bowel cleansing protocol for colonoscopy procedures.展开更多
AIM: To assess the tolerability and safety of same-day tandem procedures, endoscopic ultrasound (EUS) followed by endoscopic retrograde cholangiopancreatography (ERCP) under conscious sedation. METHODS: A retrospectiv...AIM: To assess the tolerability and safety of same-day tandem procedures, endoscopic ultrasound (EUS) followed by endoscopic retrograde cholangiopancreatography (ERCP) under conscious sedation. METHODS: A retrospective review was conducted at Loma Linda University Medical Center, a tertiary-care center. All 54 patients who underwent EUS followed by ERCP (group A) from 2004 to 2006 were included in the study. A second group of 56 patients who underwent EUS only (group B), and a third group of 53 patients who underwent ERCP only (group C) during the same time period were selected consecutively as control groups for comparison. RESULTS: Conscious sedation was used in 96% of patients in group A. Mean dosages of meperidine and midazolam used in group A were signifi cantly higher than in group B or C. Mean recovery time in group A was not statistically longer than in group B or C. Therewas no signifi cant difference in the incidence of sedation-related and procedural-related complications. CONCLUSION: Tandem EUS/ERCP procedure can be safely performed under conscious sedation with minimal adverse events. Combined procedures, however, are associated with higher dosages of sedatives, and slightly longer recovery time.展开更多
As an important sensor in the navigation systems,star sensors and the gyro play important roles in spacecraft attitude determination system.Complex environmental factors are the main sources of error in attitude deter...As an important sensor in the navigation systems,star sensors and the gyro play important roles in spacecraft attitude determination system.Complex environmental factors are the main sources of error in attitude determination.The error influence of different benchmarks and the disintegration mode between the star sensor and the gyro is analyzed in theory.The integrated design of the star sensor and the gyro on the same benchmark can effectively avoid the error influence and improves the spacecraft attitude determination accuracy.Simulation results indicate that when the stars sensor optical axis vectors overlap the reference coordinate axis of the gyro in the same benchmark,the attitude determination accuracy improves.展开更多
This paper suggests a scheme of electromagnetic chirality-induced negative refraction utilizing magneto-lectric cross coupling in a four-level atomic system. The negative refraction can be achieved with the two chiral...This paper suggests a scheme of electromagnetic chirality-induced negative refraction utilizing magneto-lectric cross coupling in a four-level atomic system. The negative refraction can be achieved with the two chirality coefficients having the same amplitude but the opposite phase, without requiring the simultaneous presence of an electric-dipole and a magnetic-dipole transition near the same transition frequency.展开更多
In order to improve the reliability of fault identification of the double-circuit transmission lines on the same tower, a new algorithm for fast protection of double-circuit transmission lines on the same tower based ...In order to improve the reliability of fault identification of the double-circuit transmission lines on the same tower, a new algorithm for fast protection of double-circuit transmission lines on the same tower based on the reactive powers of traveling wave is proposed. With the implementation of S-transform, the initial traveling wave reactive powers are calculated and the change characteristics of reactive power under different fault conditions are studied. The protection criterion is constructed by analyzing the ratio of the reactive powers of the same end on double-circuit transmission lines and the ratio of the reactive powers at both ends on the same line. According to the ratio of reactive power on the same side of the line and both ends of the same line, it is possible to identify whether the faults of the double-circuit line of the same tower occurred in or out of the protection zone. A large number of simulation results show that the protection performance is sensitive and reliable, and quick to respond. The criterion is simple and is basically not affected by fault initial angles, fault types, and transitional resistances.展开更多
The theme of this article is mainly to explore the application of the"Sameness Relation"into the Chinese-English trans-lation practice.In view of the theoretical guidance of sameness relation into the practi...The theme of this article is mainly to explore the application of the"Sameness Relation"into the Chinese-English trans-lation practice.In view of the theoretical guidance of sameness relation into the practice of the Chinese-English translation,this pa-per first points out a liable mistake in Chinese-English translation due to an inadequate knowledge of the"Sense Relations",andthen defines the linguistic term"sense relations","Sameness relation""and relevant "Semantics".Next this text continues to ana-lyze how the sameness relations are applied into the translation from the five main aspects.The reference and help of the samenessrelations finally demonstrate the realistic importance of the semantics to the Chinese-English translation,attracting much wider at-tention to other linguistic theories which is great of value to Chinese-English translation.展开更多
Chinese and English are two very different languages; the former belongs to the Sino-Tibetan Language Family and the latter the Indo-European Language Family. In terms of textual organization, they show substantial di...Chinese and English are two very different languages; the former belongs to the Sino-Tibetan Language Family and the latter the Indo-European Language Family. In terms of textual organization, they show substantial differences. Chinese is mainly a pragmatic, paratactic and topic-prominent language, while English a grammatical, hypotactic and subject-prominent language. This thesis gives a contrastive study of two problems in English and Chinese. They are repeated references to the same thing and parallel structure. In this way, the translation work will be more succinct and smooth.展开更多
文摘In recent years,several failures of double circuit transmission line on the same tower due to lightning were happened in Beijing power grid.Although it can be reclosed successful,the lightning strike caused a grave threat to the power grid security.The cause of the accident and the accident process were studied for the sake of further understanding of the impact of lightning on power grid.As an example,110 kV double circuit transmission line(Xilong-line) was analyzed.At first,the system topology was given.Through the analysis on relay protection actions and the fault recorder data,over voltage on the insulator strings was calculated.Based on the analysis and the calculation,accident cause and the process were presented respectively.Secondly,it comes to the conclusion that the lightning failure was caused by counterattack.The wave of the lightning over voltage would spread to the not grounded neutral point of the transformers,and make the neutral protective gap breakdown,then cause freewheeling with the frequency of 50 Hz.As results of the relay protection,the double circuit transmission line all tripped out.Finally,the causes of the accident were proposed that included terrain features,large corner towers,strong thunderstorm weather and poor grounded contact of the tower.
文摘AIM:To evaluate the efficacy of same-day bowel preparation with Senna alkaloids combined with bisacodyl tablets in routine colonoscopy procedures.METHODS:Between March and June 2013,a sameday bowel preparation was implemented in our endoscopy unit.The preparation consisted of a semi-liquid,fiber-free diet one day prior to the procedure,with two bisacodyl tablets after lunch and dinner,and 250 mL of Senna alkaloid with 1.5 L of drinking water at 6 am the day of the procedure.The quality control parameters of colonoscopy were evaluated and implemented according to the guidelines of the American Society for Gastrointestinal Endoscopy.The pre-procedure,duringprocedure and post-procedure patient data were collected and analyzed:(1) pre-procedure(age,gender,comorbid diseases,colonoscopy indications,complete lack of compliance with the bowel preparation protocol);(2) during-procedure(sedation dose,duration of colonoscopy,withdrawal time,cecal intubation rate,polyp detection rate,Boston Bowel Preparation Scores and presence of foam and clear liquid); and(3) postprocedure(visual analogue scale score,pain during the procedure,patient satisfaction and premature withdrawal due to the insufficient bowel preparation).RESULTS:A total of 75 patients were included in this study with a mean age of 54.64 ± 13.29 years; 53.3%(40/75) were female and 46.7%(35/75) were male.A complete lack of compliance with the bowel preparation protocol was seen in 6.7% of patients(5/75).The mean total duration of colonoscopy was 16.12 ± 6.51 min,and the mean withdrawal time was 8.89 ± 4.07 min.The cecal intubation rate was 93.8%(61/64) and the polyp detection rate was 40%(30/75).The mean Boston Bowel Preparation Score was 7.38 ± 1.81,with the following distribution:right colon,2.34 ± 0.89; transverse colon,2.52 ± 0.67; left colon,2.52 ± 0.63.The mean visual analogue scale score was 4.59 ± 1.57.Due to insufficient bowel preparation,seven patients(7/75; 9.3%) were asked to repeat the procedure.Of these,five patients had poor or modest compliance with the protocol,and two patients reported constipation.Premature withdrawal due to insufficient bowel preparation was 2.7%(2/75).The overall satisfaction with the protocol was 86.7%(65/75),with patients reporting they would prefer the same protocol in a repeat procedure.CONCLUSION:The same-day administration of Senna alkaloids appears to be a safe and effective bowel cleansing protocol for colonoscopy procedures.
文摘AIM: To assess the tolerability and safety of same-day tandem procedures, endoscopic ultrasound (EUS) followed by endoscopic retrograde cholangiopancreatography (ERCP) under conscious sedation. METHODS: A retrospective review was conducted at Loma Linda University Medical Center, a tertiary-care center. All 54 patients who underwent EUS followed by ERCP (group A) from 2004 to 2006 were included in the study. A second group of 56 patients who underwent EUS only (group B), and a third group of 53 patients who underwent ERCP only (group C) during the same time period were selected consecutively as control groups for comparison. RESULTS: Conscious sedation was used in 96% of patients in group A. Mean dosages of meperidine and midazolam used in group A were signifi cantly higher than in group B or C. Mean recovery time in group A was not statistically longer than in group B or C. Therewas no signifi cant difference in the incidence of sedation-related and procedural-related complications. CONCLUSION: Tandem EUS/ERCP procedure can be safely performed under conscious sedation with minimal adverse events. Combined procedures, however, are associated with higher dosages of sedatives, and slightly longer recovery time.
文摘As an important sensor in the navigation systems,star sensors and the gyro play important roles in spacecraft attitude determination system.Complex environmental factors are the main sources of error in attitude determination.The error influence of different benchmarks and the disintegration mode between the star sensor and the gyro is analyzed in theory.The integrated design of the star sensor and the gyro on the same benchmark can effectively avoid the error influence and improves the spacecraft attitude determination accuracy.Simulation results indicate that when the stars sensor optical axis vectors overlap the reference coordinate axis of the gyro in the same benchmark,the attitude determination accuracy improves.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60768001 and 10464002)
文摘This paper suggests a scheme of electromagnetic chirality-induced negative refraction utilizing magneto-lectric cross coupling in a four-level atomic system. The negative refraction can be achieved with the two chirality coefficients having the same amplitude but the opposite phase, without requiring the simultaneous presence of an electric-dipole and a magnetic-dipole transition near the same transition frequency.
文摘In order to improve the reliability of fault identification of the double-circuit transmission lines on the same tower, a new algorithm for fast protection of double-circuit transmission lines on the same tower based on the reactive powers of traveling wave is proposed. With the implementation of S-transform, the initial traveling wave reactive powers are calculated and the change characteristics of reactive power under different fault conditions are studied. The protection criterion is constructed by analyzing the ratio of the reactive powers of the same end on double-circuit transmission lines and the ratio of the reactive powers at both ends on the same line. According to the ratio of reactive power on the same side of the line and both ends of the same line, it is possible to identify whether the faults of the double-circuit line of the same tower occurred in or out of the protection zone. A large number of simulation results show that the protection performance is sensitive and reliable, and quick to respond. The criterion is simple and is basically not affected by fault initial angles, fault types, and transitional resistances.
文摘The theme of this article is mainly to explore the application of the"Sameness Relation"into the Chinese-English trans-lation practice.In view of the theoretical guidance of sameness relation into the practice of the Chinese-English translation,this pa-per first points out a liable mistake in Chinese-English translation due to an inadequate knowledge of the"Sense Relations",andthen defines the linguistic term"sense relations","Sameness relation""and relevant "Semantics".Next this text continues to ana-lyze how the sameness relations are applied into the translation from the five main aspects.The reference and help of the samenessrelations finally demonstrate the realistic importance of the semantics to the Chinese-English translation,attracting much wider at-tention to other linguistic theories which is great of value to Chinese-English translation.
基金The project supported by the Key Project5 of National Natural Science Foundation of China under Grant No 70431002, and National Natural Science Foundation of China under Grant Nos. 70371068 and 10247005
文摘基于我们以前建议了的所有节点的一样的度的模型，一个新算法，“在整个顶点的所谓的传播(SAV ) ”算法，从一枚常规戒指为 generatingsmall 世界性质被建议格子。在随机给连接换新电线期间， SAV 被用来保留连接的未改变的数字。把 SAV 算法与在整个边界的 Watts-Strogatzmodel 和“传播”作比较算法，三个方法能有小世界网络的一样的拓扑的性质。这些结果提供小世界网络的多样的形成。它对为在与网络联系的节点和交往的自动机内的相互的振荡器的动力学的一些应用的研究有用。
基金The project supported by the National Fundamental Research Program of China under Grant No. 001CB309308, National Natural Science Foundation of China under Grant Nos. 60433050 and 10325521, and the SRDP program of the Ministry of Education, China
基金supported by the Korea Research Foundation Grant funded by the Korean Government(MOEHRD),the MKE(The Ministry of Knowledge Economy,Korea)the ITRC(Information Technology Research Center)support program(NIPA-2009-(C1090-0902-0007))
文摘Chinese and English are two very different languages; the former belongs to the Sino-Tibetan Language Family and the latter the Indo-European Language Family. In terms of textual organization, they show substantial differences. Chinese is mainly a pragmatic, paratactic and topic-prominent language, while English a grammatical, hypotactic and subject-prominent language. This thesis gives a contrastive study of two problems in English and Chinese. They are repeated references to the same thing and parallel structure. In this way, the translation work will be more succinct and smooth.
