This paper proposes a simple method to enlarge the estimation range of conventional carrier frequency offset (CFO) estimation methods based on correlations among the identical parts of the preamble. A novel preamble i...This paper proposes a simple method to enlarge the estimation range of conventional carrier frequency offset (CFO) estimation methods based on correlations among the identical parts of the preamble. A novel preamble is designed, which is composed of one regular OFDM training block with even numbers of identical parts and one irregular OFDM training block with odd numbers of identical parts. The initial estimates obtained over the two training blocks are next exploited to jointly estimate the CFO. By elaborately selecting the numbers of identical parts for the two training blocks, the proposed CFO estimator can estimate frequency offset over tens of the subcarrier spacing. Simulation results showed that the proposed CFO estimator satisfies the estimate range requirement for the practical OFDM systems, while achieving a very good estimate performance.展开更多
AIM To analyze the homogeneity of pathologic response to preoperative chemotherapy(PRPC) after chemotherapy in patients with multiple liver metastases(LM).METHODS From September 2011 to August 2014,patients with at le...AIM To analyze the homogeneity of pathologic response to preoperative chemotherapy(PRPC) after chemotherapy in patients with multiple liver metastases(LM).METHODS From September 2011 to August 2014,patients with at least two LM undergoing preoperative chemotherapy prior to resection were included in this retrospective,single-center study. The endpoints were PRPC homogeneity(according to both the Rubbia-Brandt and MD Anderson classifications),the impact of PRPC on the MDT decision,factors associated with homogeneous PRPC and overall survival of patients with vs. without homogeneous PRPC.RESULTS seventy-three patients with a total of 88 liver resections(including 15 two-stage procedures) were included in the study. The homogeneous PRPC rate was 55% according to the Rubbia-Brandt classification and 53% according to the MD Anderson classification. The MDT decision was modified by the PRPC in only 2.7% of patients(n = 2). CONCLUSION The PRPC was homogeneous in only one half of patients and had very little influence on the MDT decision.展开更多
The inception of radioisotope and its application in China are introduced. The research,development, production, application progress and the future development prospect of radioisotope and its products are described.
[Objective] This research aimed to study the pre-treatment conditions of head space so as to establish a HS-GC determination method, which is suitable for China's conditions, for trace volatile organic compounds i...[Objective] This research aimed to study the pre-treatment conditions of head space so as to establish a HS-GC determination method, which is suitable for China's conditions, for trace volatile organic compounds in drinking water. [Method]The preparation method of head space was adopted for the volatile organic compounds in drinking water. [Result] The 20 kinds of volatile organic compounds in drinking water all could be detected simultaneously by using HS-GC-FID method,and they all could be separated well. The HS-GC-FID method could analyze the detected substances qualitatively and quantitatively. In addition, this detection method was characterized by larger linear range of concentration, higher precision, higher detection limit and higher recovery rate. [Conclusion] Under certain conditions, HSGC can reduce the loss of volatile organic compound in drinking water and improve the sensitivity of detection. Moreover, the detection results meet the requirements by quality control.展开更多
Data assimilation is the process by which measurements and model predictions are combined to obtain an accurate representation of the state of the modeled system. We implemented a data assimilation scheme called LETKF...Data assimilation is the process by which measurements and model predictions are combined to obtain an accurate representation of the state of the modeled system. We implemented a data assimilation scheme called LETKF （local ensemble transform Kalman filter） with FSUGSM （Florida State University Global Spectral Model） and made an experiment to evaluate the initial condition generated to numerical weather prediction to FSUGSM model. The LETKF analysis carries out independently at each grid point with the use of ＂local＂ observations. An ensemble of estimates in state space represents uncertainty. The FSUGSM is a multilevel （27 vertical levels） spectral primitive equation model, where the variables are expanded horizontally in a truncated series of spherical harmonic functions （at resolution T63） and a transform technique is applied to calculate the physical processes in real space The assimilation cycle runs on the period 01/01/2001 to 31/01/2001 at （00, 06, 12 and 18 GMT） for each day. We examined the atmospheric fields during the period and the OMF （observation-minus-forecast） and the OMA （observation-minus-analysis） statistics to verify the analysis quality comparing with forecasts and observations. The analyses present stability and show suitable to initiate the weather predictions.展开更多
In this paper, after discussing some properties of quotient contexts of a Morira context, well show that if DR is a perfect Gopriel topology, the quotient context of (P, Q), where (P, Q) as all MC between rings R and...In this paper, after discussing some properties of quotient contexts of a Morira context, well show that if DR is a perfect Gopriel topology, the quotient context of (P, Q), where (P, Q) as all MC between rings R and S is the quotient context of (P, Q), is isomorphic to a quotient context of (P, Q).展开更多
The existing δ 13C data in the Cambrian from different regions of the world are analyzed here. There are four well-documented carbon isotope excursions with global significance. In ascending order, they are： （1） a...The existing δ 13C data in the Cambrian from different regions of the world are analyzed here. There are four well-documented carbon isotope excursions with global significance. In ascending order, they are： （1） a large negative excursion, comparable to ＂BACE＂ （BAsal Cambrian Carbon isotope Excursion） event, which occurs near the Precambrian-Cambrian boundary with a magnitude of 4‰-10‰ （PDB）; （2） the ＂ZHUCE＂ （ZHUjiaqing Carbon isotope Excursion） event, a distinct positive excursion （over 5%0） that can be recognized at the Fortunian Stage to Stage 2 transition; （3） another strong negative one, so-called ＂ROECE＂ （Redlichiid-Olenellid Extinction Carbon isotope Excursion） event, shifting at the interval between Series 2 and Series 3, peaking at -3‰--5‰ （PDB）; （4） the famous Steptoean positive carbon isotope excursion （SPICE）, which has been widely identified at the base of Furongian Series, Paibian Stage, with an amplitude about 4‰ （PDB）. The four sharp σ13C shifts correlate well with coeval paleoceanographic changes and bioevents. Besides, there are some σ13C excursions from a few sections in previous studies, and more data are required to identify whether they are global or regional ones.展开更多
To meet the urgent requirement of enterprises for three-dimensional (3D) process models, an approach based on subgraph isomorphism is proposed to solve the matching problem between precursory 3D process model and 2D w...To meet the urgent requirement of enterprises for three-dimensional (3D) process models, an approach based on subgraph isomorphism is proposed to solve the matching problem between precursory 3D process model and 2D working procedure drawings. First, the projection drawings of the precursory 3D process model are obtained, then the primitives are extracted and the attributed adjacency graph (AAG) is constructed. Finally, by taking the 2D working procedure drawing as the AAG, and the projection drawing as the whole AAG, the matching problem between precursory 3D process model and 2D working procedure drawings is translated into the problem of subgraph isomorphism. To raise the matching efficiency, the AAG is partitioned, and the vertexes of the graph are classified effectively using the vertex’s attributes. Experimental results show that this method is able to support exact match and the matching efficiency can meet the requirement of practical applications.展开更多
Background:A small percentage of incomplete optical colonoscopies(OCs)are the result of an obstructing tumor.According to current guidelines,CT colonography(CTC)is performed to prevent missing a synchronous tumor.The ...Background:A small percentage of incomplete optical colonoscopies(OCs)are the result of an obstructing tumor.According to current guidelines,CT colonography(CTC)is performed to prevent missing a synchronous tumor.The aim of this study was to evaluate how frequently a synchronous tumor was found on CTC and how often this led to a change in the surgical plan.Methods:In this retrospective study,a total of 267 patients underwent CTC after an incomplete OC as a result of an obstructing colorectal carcinoma(CRC).Among them,210 patients undergoing surgery met the inclusion criteria and were included in the analysis.The OC report,CTC report and surgical report of these patients were retrospectively evaluated for the presence of synchronous tumors using surgery and post-operative colonoscopy as the gold standard.Results:Six of the 210 patients(2.9%)showed signs of a synchronous CRC proximal to the obstructing tumor on CTC.In three of these patients,a synchronous CRC was confirmed during surgery.All these tumors caused a change in the surgical plan.Three out of the six tumors found on CTC were found to be large,non-malignant polyps.All these polyps were located in the same segment as the obstructing tumor and therefore did not alter the surgical plan.Conclusion:In patients with obstructing CRC,the frequency of synchronous CRCs proximal to this lesion is low.Performing a CTC leads to a change in surgical plan based on the presence of these synchronous tumors in 1.4%of the cases.CTC should be employed as a one-stop shop in patients with an obstructing CRC.展开更多
基金Project supported by the Hi-Tech Research and Development Pro-gram (863) of China (No. 2003AA12331007) and the National NaturalScience Foundation of China (No. 60572157)
文摘This paper proposes a simple method to enlarge the estimation range of conventional carrier frequency offset (CFO) estimation methods based on correlations among the identical parts of the preamble. A novel preamble is designed, which is composed of one regular OFDM training block with even numbers of identical parts and one irregular OFDM training block with odd numbers of identical parts. The initial estimates obtained over the two training blocks are next exploited to jointly estimate the CFO. By elaborately selecting the numbers of identical parts for the two training blocks, the proposed CFO estimator can estimate frequency offset over tens of the subcarrier spacing. Simulation results showed that the proposed CFO estimator satisfies the estimate range requirement for the practical OFDM systems, while achieving a very good estimate performance.
文摘AIM To analyze the homogeneity of pathologic response to preoperative chemotherapy(PRPC) after chemotherapy in patients with multiple liver metastases(LM).METHODS From September 2011 to August 2014,patients with at least two LM undergoing preoperative chemotherapy prior to resection were included in this retrospective,single-center study. The endpoints were PRPC homogeneity(according to both the Rubbia-Brandt and MD Anderson classifications),the impact of PRPC on the MDT decision,factors associated with homogeneous PRPC and overall survival of patients with vs. without homogeneous PRPC.RESULTS seventy-three patients with a total of 88 liver resections(including 15 two-stage procedures) were included in the study. The homogeneous PRPC rate was 55% according to the Rubbia-Brandt classification and 53% according to the MD Anderson classification. The MDT decision was modified by the PRPC in only 2.7% of patients(n = 2). CONCLUSION The PRPC was homogeneous in only one half of patients and had very little influence on the MDT decision.
文摘The inception of radioisotope and its application in China are introduced. The research,development, production, application progress and the future development prospect of radioisotope and its products are described.
文摘[Objective] This research aimed to study the pre-treatment conditions of head space so as to establish a HS-GC determination method, which is suitable for China's conditions, for trace volatile organic compounds in drinking water. [Method]The preparation method of head space was adopted for the volatile organic compounds in drinking water. [Result] The 20 kinds of volatile organic compounds in drinking water all could be detected simultaneously by using HS-GC-FID method,and they all could be separated well. The HS-GC-FID method could analyze the detected substances qualitatively and quantitatively. In addition, this detection method was characterized by larger linear range of concentration, higher precision, higher detection limit and higher recovery rate. [Conclusion] Under certain conditions, HSGC can reduce the loss of volatile organic compound in drinking water and improve the sensitivity of detection. Moreover, the detection results meet the requirements by quality control.
文摘Data assimilation is the process by which measurements and model predictions are combined to obtain an accurate representation of the state of the modeled system. We implemented a data assimilation scheme called LETKF （local ensemble transform Kalman filter） with FSUGSM （Florida State University Global Spectral Model） and made an experiment to evaluate the initial condition generated to numerical weather prediction to FSUGSM model. The LETKF analysis carries out independently at each grid point with the use of ＂local＂ observations. An ensemble of estimates in state space represents uncertainty. The FSUGSM is a multilevel （27 vertical levels） spectral primitive equation model, where the variables are expanded horizontally in a truncated series of spherical harmonic functions （at resolution T63） and a transform technique is applied to calculate the physical processes in real space The assimilation cycle runs on the period 01/01/2001 to 31/01/2001 at （00, 06, 12 and 18 GMT） for each day. We examined the atmospheric fields during the period and the OMF （observation-minus-forecast） and the OMA （observation-minus-analysis） statistics to verify the analysis quality comparing with forecasts and observations. The analyses present stability and show suitable to initiate the weather predictions.
文摘In this paper, after discussing some properties of quotient contexts of a Morira context, well show that if DR is a perfect Gopriel topology, the quotient context of (P, Q), where (P, Q) as all MC between rings R and S is the quotient context of (P, Q), is isomorphic to a quotient context of (P, Q).
基金supported by National Science and Technology Major Project (Grant No. 2008ZX05004)Major Project of China National Petroleum Corporation (Grant No. 2008E-0702)
文摘The existing δ 13C data in the Cambrian from different regions of the world are analyzed here. There are four well-documented carbon isotope excursions with global significance. In ascending order, they are： （1） a large negative excursion, comparable to ＂BACE＂ （BAsal Cambrian Carbon isotope Excursion） event, which occurs near the Precambrian-Cambrian boundary with a magnitude of 4‰-10‰ （PDB）; （2） the ＂ZHUCE＂ （ZHUjiaqing Carbon isotope Excursion） event, a distinct positive excursion （over 5%0） that can be recognized at the Fortunian Stage to Stage 2 transition; （3） another strong negative one, so-called ＂ROECE＂ （Redlichiid-Olenellid Extinction Carbon isotope Excursion） event, shifting at the interval between Series 2 and Series 3, peaking at -3‰--5‰ （PDB）; （4） the famous Steptoean positive carbon isotope excursion （SPICE）, which has been widely identified at the base of Furongian Series, Paibian Stage, with an amplitude about 4‰ （PDB）. The four sharp σ13C shifts correlate well with coeval paleoceanographic changes and bioevents. Besides, there are some σ13C excursions from a few sections in previous studies, and more data are required to identify whether they are global or regional ones.
基金supported by the National Natural Science Foundation of China (Grant No. 51075336)the National High Technology Research and Development Program of China (Grant No. 2007AA04Z137)
文摘To meet the urgent requirement of enterprises for three-dimensional (3D) process models, an approach based on subgraph isomorphism is proposed to solve the matching problem between precursory 3D process model and 2D working procedure drawings. First, the projection drawings of the precursory 3D process model are obtained, then the primitives are extracted and the attributed adjacency graph (AAG) is constructed. Finally, by taking the 2D working procedure drawing as the AAG, and the projection drawing as the whole AAG, the matching problem between precursory 3D process model and 2D working procedure drawings is translated into the problem of subgraph isomorphism. To raise the matching efficiency, the AAG is partitioned, and the vertexes of the graph are classified effectively using the vertex’s attributes. Experimental results show that this method is able to support exact match and the matching efficiency can meet the requirement of practical applications.
文摘Background:A small percentage of incomplete optical colonoscopies(OCs)are the result of an obstructing tumor.According to current guidelines,CT colonography(CTC)is performed to prevent missing a synchronous tumor.The aim of this study was to evaluate how frequently a synchronous tumor was found on CTC and how often this led to a change in the surgical plan.Methods:In this retrospective study,a total of 267 patients underwent CTC after an incomplete OC as a result of an obstructing colorectal carcinoma(CRC).Among them,210 patients undergoing surgery met the inclusion criteria and were included in the analysis.The OC report,CTC report and surgical report of these patients were retrospectively evaluated for the presence of synchronous tumors using surgery and post-operative colonoscopy as the gold standard.Results:Six of the 210 patients(2.9%)showed signs of a synchronous CRC proximal to the obstructing tumor on CTC.In three of these patients,a synchronous CRC was confirmed during surgery.All these tumors caused a change in the surgical plan.Three out of the six tumors found on CTC were found to be large,non-malignant polyps.All these polyps were located in the same segment as the obstructing tumor and therefore did not alter the surgical plan.Conclusion:In patients with obstructing CRC,the frequency of synchronous CRCs proximal to this lesion is low.Performing a CTC leads to a change in surgical plan based on the presence of these synchronous tumors in 1.4%of the cases.CTC should be employed as a one-stop shop in patients with an obstructing CRC.
