Loose phrase extraction method is proposed and applied for phrase-based statistical ma- chine translation. The method extracts phrase pairs that are not strictly consistent with word align- ments. Two types of constra...Loose phrase extraction method is proposed and applied for phrase-based statistical ma- chine translation. The method extracts phrase pairs that are not strictly consistent with word align- ments. Two types of constraints on word positions are investigated for this method. Furthermore, n-best alignments are introduced for phrase extraction instead of the one-best. Experimental results show that the proposed approach outperforms the baseline system, Pharaoh system, for both one-best and n-best alignments.展开更多
Aim:To survey existing ophthalmic follow up protocols in the United Kingdom for very low birth weight(VLBW)children.In addition,relative risk analysis was performed using data from a cohort study to assess which facto...Aim:To survey existing ophthalmic follow up protocols in the United Kingdom for very low birth weight(VLBW)children.In addition,relative risk analysis was performed using data from a cohort study to assess which factors(birth weight,gestational age,retinopathy of prematurity(ROP)status)led to a high risk of developing amblyogenic factors.Methods:Questionnaires were sent to every orthoptic department in the United Kingdom(n=288)for information on their policy on the follow up of VLBW children.Results:Responses were received from 125 departments(43%).There was a large variation in criteria used for follow up;21% of respondents using birth weight(BW)and gestational age(GA),22% using stage 3 or treated ROP,the remainder using a combination of these factors.There was no consensus regarding when follow up should commence(from 3 months to 3 years)or cease(1-8 years).Relative risk analysis revealed that birth weight under 1500 g,GA under 33 weeks,and the presence of severe ROP were significant risk factors for developing one or more amblyogenic factors.Conclusion:There is no consensus on whether VLBW children need to be reviewed.There is a greatly increased risk of ophthalmic deficits in those with severe ROP or severe neurological disorders,and also in those with mild or no ROP.Children in the latter group who are not routinely followed up,have a high risk of developing treatable refractive errors and strabismus.This raises the question of whether an additional screening examination is merited.展开更多
This paper considers the Geom/G/1 queueing model with feedback according to a late arrival system with delayed access （LASDA）. Using recursive method, this paper studies the transient property of the queue size from...This paper considers the Geom/G/1 queueing model with feedback according to a late arrival system with delayed access （LASDA）. Using recursive method, this paper studies the transient property of the queue size from the initial state N（0＋） = i. Some new results about the recursive expression of the transient queue size distribution at any epoch n＋ and the recursive formulae of the equilibrium distribution are obtained. Furthermore, the recursive formulae of the equilibrium queue size distribution at epoch n-, and n are obtained, too. The important relations between stationary queue size distributions at different epochs are discovered （being different from the relations given in M/G/I queueing system）. The model discussed in this paper can be widely applied in all kinds of communications and computer network.展开更多
基金the High Technology Research and Develop-ment Program of China (No.2004AA117010-08).
文摘Loose phrase extraction method is proposed and applied for phrase-based statistical ma- chine translation. The method extracts phrase pairs that are not strictly consistent with word align- ments. Two types of constraints on word positions are investigated for this method. Furthermore, n-best alignments are introduced for phrase extraction instead of the one-best. Experimental results show that the proposed approach outperforms the baseline system, Pharaoh system, for both one-best and n-best alignments.
文摘Aim:To survey existing ophthalmic follow up protocols in the United Kingdom for very low birth weight(VLBW)children.In addition,relative risk analysis was performed using data from a cohort study to assess which factors(birth weight,gestational age,retinopathy of prematurity(ROP)status)led to a high risk of developing amblyogenic factors.Methods:Questionnaires were sent to every orthoptic department in the United Kingdom(n=288)for information on their policy on the follow up of VLBW children.Results:Responses were received from 125 departments(43%).There was a large variation in criteria used for follow up;21% of respondents using birth weight(BW)and gestational age(GA),22% using stage 3 or treated ROP,the remainder using a combination of these factors.There was no consensus regarding when follow up should commence(from 3 months to 3 years)or cease(1-8 years).Relative risk analysis revealed that birth weight under 1500 g,GA under 33 weeks,and the presence of severe ROP were significant risk factors for developing one or more amblyogenic factors.Conclusion:There is no consensus on whether VLBW children need to be reviewed.There is a greatly increased risk of ophthalmic deficits in those with severe ROP or severe neurological disorders,and also in those with mild or no ROP.Children in the latter group who are not routinely followed up,have a high risk of developing treatable refractive errors and strabismus.This raises the question of whether an additional screening examination is merited.
基金supported by the National Natural Science Foundation of China under Grant No. 70871084the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No 200806360001the Scientific Research Fund of Southwestern University of Finance and Economics
文摘This paper considers the Geom/G/1 queueing model with feedback according to a late arrival system with delayed access （LASDA）. Using recursive method, this paper studies the transient property of the queue size from the initial state N（0＋） = i. Some new results about the recursive expression of the transient queue size distribution at any epoch n＋ and the recursive formulae of the equilibrium distribution are obtained. Furthermore, the recursive formulae of the equilibrium queue size distribution at epoch n-, and n are obtained, too. The important relations between stationary queue size distributions at different epochs are discovered （being different from the relations given in M/G/I queueing system）. The model discussed in this paper can be widely applied in all kinds of communications and computer network.
