Shared Memory (SM) switches are widely used for its high throughput, low delay and efficient use of memory. This paper compares the performance of two prominent switching schemes of SM packet switches: Cell-Based Swit...Shared Memory (SM) switches are widely used for its high throughput, low delay and efficient use of memory. This paper compares the performance of two prominent switching schemes of SM packet switches: Cell-Based Switching (CBS) and Packet-Based Switching (PBS).Theoretical analysis is carried out to draw qualitative conclusion on the memory requirement,throughput and packet delay of the two schemes. Furthermore, simulations are carried out to get quantitative results of the performance comparison under various system load, traffic patterns,and memory sizes. Simulation results show that PBS has the advantage of shorter time delay while CBS has lower memory requirement and outperforms in throughput when the memory size is limited. The comparison can be used for tradeoff between performance and complexity in switch design.展开更多
A new weighted fair queueing algorithm is proposed, which uses the novel flow-based service ratio parameters to schedule flows. This solves the main drawback of traditional weighted fair queneing algorithms- the packe...A new weighted fair queueing algorithm is proposed, which uses the novel flow-based service ratio parameters to schedule flows. This solves the main drawback of traditional weighted fair queneing algorithms- the packet-based calculation of the weight parameters. In addition, this paper proposes a novel service ratio calculation method and a queue mangement technology. The former adjusts the service ratio parameters adaptively based on the dynamics of the packet lengths and thee solves the unfairness problem induced by the variable packet length. The latter improves the utilization of the server＇s queue buffer and reduces the delay jitter through restricting the buffer length for each flow.展开更多
Transitional cell carcinoma （TCC） of the ovary is a rare and recently recognized subtype of ovarian epithelial cancer. We presented the first case report from our Institute （Sheri Kashmir Instiute of Medical Scienc...Transitional cell carcinoma （TCC） of the ovary is a rare and recently recognized subtype of ovarian epithelial cancer. We presented the first case report from our Institute （Sheri Kashmir Instiute of Medical Sciences, Srinagar, India）, which was initially rnisdiagnosed as stromal cell carcinoma （granulosa cell tumour）, and on review of histopathology with immunohistochemistry, the diagnosis of TCC of the ovary was established. The aim of this article was to describe the typical case of primary TCC of the ovary and to review the literature for information on TCC management.展开更多
Multicentric gliomas are considered to be well recognized but uncommon; often scatter widely in different lobes or hemispheres; and cannot be attributed to a definite pathwayEll. A patient diagnosed as multicentric gl...Multicentric gliomas are considered to be well recognized but uncommon; often scatter widely in different lobes or hemispheres; and cannot be attributed to a definite pathwayEll. A patient diagnosed as multicentric gliomas is presented in this paper. He was firstly misdiagnosed as cerebral metastatic tumors, but later the histopathological examination revealed them to be glioblastoma （WHO grade IV）. Additionally, the aim of the paper was to describe the case history of the patient and the problems encountered in the pathogenesis, pathophysiology, diagnosis and treatment.展开更多
Anterior cruciate ligament （ACL） reconstruction is usually recommended for young patients. Several recent articles have however reported comparable outcomes of ACL reconstruction between youth and patients in fourth...Anterior cruciate ligament （ACL） reconstruction is usually recommended for young patients. Several recent articles have however reported comparable outcomes of ACL reconstruction between youth and patients in fourth or fifth age group. But in the literature there are not many reports about ACL reconstruction in patients over 70 years old. We report a case of a successful arthroscopic ACL reconstruction （using single bundle quadrupled hamstring graft） in an active 75-year-old medical practitioner. Successful outcome after ACL reconstruction can be achieved in selected older patients; chronological age is no barrier.展开更多
基金Supported by the National Natural Science Foundation of China(No.69896242).
文摘Shared Memory (SM) switches are widely used for its high throughput, low delay and efficient use of memory. This paper compares the performance of two prominent switching schemes of SM packet switches: Cell-Based Switching (CBS) and Packet-Based Switching (PBS).Theoretical analysis is carried out to draw qualitative conclusion on the memory requirement,throughput and packet delay of the two schemes. Furthermore, simulations are carried out to get quantitative results of the performance comparison under various system load, traffic patterns,and memory sizes. Simulation results show that PBS has the advantage of shorter time delay while CBS has lower memory requirement and outperforms in throughput when the memory size is limited. The comparison can be used for tradeoff between performance and complexity in switch design.
基金National Natural Science Foundation of China ( No.60572157)Sharp Corporation of Japanthe Hi-Tech Research and Development Program(863) of China (No.2003AA123310)
文摘A new weighted fair queueing algorithm is proposed, which uses the novel flow-based service ratio parameters to schedule flows. This solves the main drawback of traditional weighted fair queneing algorithms- the packet-based calculation of the weight parameters. In addition, this paper proposes a novel service ratio calculation method and a queue mangement technology. The former adjusts the service ratio parameters adaptively based on the dynamics of the packet lengths and thee solves the unfairness problem induced by the variable packet length. The latter improves the utilization of the server＇s queue buffer and reduces the delay jitter through restricting the buffer length for each flow.
文摘Transitional cell carcinoma （TCC） of the ovary is a rare and recently recognized subtype of ovarian epithelial cancer. We presented the first case report from our Institute （Sheri Kashmir Instiute of Medical Sciences, Srinagar, India）, which was initially rnisdiagnosed as stromal cell carcinoma （granulosa cell tumour）, and on review of histopathology with immunohistochemistry, the diagnosis of TCC of the ovary was established. The aim of this article was to describe the typical case of primary TCC of the ovary and to review the literature for information on TCC management.
文摘Multicentric gliomas are considered to be well recognized but uncommon; often scatter widely in different lobes or hemispheres; and cannot be attributed to a definite pathwayEll. A patient diagnosed as multicentric gliomas is presented in this paper. He was firstly misdiagnosed as cerebral metastatic tumors, but later the histopathological examination revealed them to be glioblastoma （WHO grade IV）. Additionally, the aim of the paper was to describe the case history of the patient and the problems encountered in the pathogenesis, pathophysiology, diagnosis and treatment.
文摘Anterior cruciate ligament （ACL） reconstruction is usually recommended for young patients. Several recent articles have however reported comparable outcomes of ACL reconstruction between youth and patients in fourth or fifth age group. But in the literature there are not many reports about ACL reconstruction in patients over 70 years old. We report a case of a successful arthroscopic ACL reconstruction （using single bundle quadrupled hamstring graft） in an active 75-year-old medical practitioner. Successful outcome after ACL reconstruction can be achieved in selected older patients; chronological age is no barrier.
