Wide angle acquisition has been taken as a significant measure to obtain high quality seismic data and is getting greater attention, In this paper, we discuss ocean bottom cable （OBC） seismic wide angle reflections ...Wide angle acquisition has been taken as a significant measure to obtain high quality seismic data and is getting greater attention, In this paper, we discuss ocean bottom cable （OBC） seismic wide angle reflections on the basis of a layered model experiment. Some experiment results don＇t support theoretical conclusions. The main experimental conclusions are： 1. Wide angle reflection energies are stronger than non-wide-angle reflections （up to twice as strong） but there is a big difference between observations and theoretical calculations that suggest the wide angle reflection energies are 15 times the non- wide-angle reflection energy. The reflection energy increases gradually rather than sharply as the theoretical calculations suggest. 2. The reflection events remain hyperbolic when the offset increases. 3. Wide angle reflection dominant frequency is about 20-30% less than non- wide-angle reflections and decreases as the offset increases. The non-wide-angle reflection dominant frequency shows no obvious variation for small offsets. 4. There is no wave shape mutation or polarity reversal near the critical angle. 5. The reflection event group features are the same for both cases of incidence angle greater and less than the critical angle. 6. Direct arrivals, multiples, and water bottom refractions influence the wide angle reflections of the sea floor.展开更多
Under the method of density functional theory, the geometry structures, values of energy and population analysis of the combo of crown tetraalanylpeptide （C4-AIa） with ions （Xn） are calculated, based on the founda...Under the method of density functional theory, the geometry structures, values of energy and population analysis of the combo of crown tetraalanylpeptide （C4-AIa） with ions （Xn） are calculated, based on the foundation of former studies. It was found that the coronary structure changed little whether in C4-Ala or C4-Ala-Xn, and the electrons transferred between C4-Ala and Xn at the mean time. There were coordinate bonds between Xn＋ and the nitrogen from -NH-, hydrogen bonds between Xa and the hydrogen from -NH-, and they became weaker when the radii of ions turned larger. Besides, the values of the single point bonding energy fluctuated gradually as a shape of saddle, but cations and anions located in opposite directions of the center of coronary structure when reach minimum, respectively.展开更多
AIM: To analyze the imaging findings of hepatic malignancy with right atrial (RA) embolus. METHODS: Forty-six patients with an embolus in the RA were diagnosed, including 44 patients with hepatocellular carcinoma (HCC...AIM: To analyze the imaging findings of hepatic malignancy with right atrial (RA) embolus. METHODS: Forty-six patients with an embolus in the RA were diagnosed, including 44 patients with hepatocellular carcinoma (HCC), 1 patient with cholangiocellular carcinoma and 1 patient with hepatic carcinoma metastasis. The diagnosis was confirmed by clinical examination, serum α-fetoprotein and imaging. Seventeen patients underwent transcatheter arterial chemoembolization (TACE). RESULTS: On enhancement computer tomography (CT) or magnetic resonance (MR) imaging, a nodular filling defect in the RA could be easily found, with a slight enhancement in the arterial phase. The coronal images of CT or MR showed the extent of lesion. Lipiodol entered the embolus after TACE, hence reducing the speed of embolus growth. There was a survival benefit for patients receiving anticancer treatment. CONCLUSION: Patients with HCC, showing a filling defect of the inferior vena cava (IVC), hepatic vein (HV) and RA on images, can be diagnosed with RA embolus. Encroachment of the RA is very rare in patients with hepatic malignancies. Furthermore, a prolongation of survival time is found in those patients who underwent TACE.展开更多
In order to improve the scalability and reliability of Software Defined Networking(SDN),many studies use multiple controllers to constitute logically centralized control plane to provide load balancing and fail over.I...In order to improve the scalability and reliability of Software Defined Networking(SDN),many studies use multiple controllers to constitute logically centralized control plane to provide load balancing and fail over.In this paper,we develop a flexible dormant multi-controller model based on the centralized multi-controller architecture.The dormant multi-controller model allows part of controllers to enter the dormant state under light traffic condition for saving system cost.Meanwhile,through queueing analysis,various performance measures of the system can be obtained.Moreover,we analyze the real traffic of China Education Network and use the results as the parameters of computer simulation and verify the effects of parameters on the system characteristics.Finally,a total expected cost function is established,and genetic algorithm is employed to find the optimal values of various parameters to minimize system cost for the deployment decision making.展开更多
AIM: To improve the preoperative diagnosis of liver metastasis from pancreatic cancer, we estimated computed tomography during arterial angiography (CTA) with/without administration of angiotensin-Ⅱ (AT-Ⅱ). METHODS:...AIM: To improve the preoperative diagnosis of liver metastasis from pancreatic cancer, we estimated computed tomography during arterial angiography (CTA) with/without administration of angiotensin-Ⅱ (AT-Ⅱ). METHODS: Thirty-fi ve patients with pancreatic cancer were examined in this study. After conventional CTA was performed, pharmacoangiographic CTA was performed with a 1-3 microgram/5 mL solution of angiotensin Ⅱ injected through a catheter into the celiac artery during spiral computed tomography. We prospectively analyzed the relative region of interest (ROI) ratio of tumor to liver with/without AT-Ⅱ. RESULTS: In all patients, the relative ratio of each computed tomography (CT) number in the ROI was larger at pharmacoangiographic CT than at conventional angiographic CT. Administration of angiotensin-Ⅱ enhanced the metastatic liver tumor as compared with normal tissue. Intratumoral blood flow increased in all patients with malignant tumors due to the pressure effect of AT-Ⅱ. Furthermore, the metastatic lesions in the liver of three patients were represented by only pharmacoangiographic CT, not by conventional CT and conventional CT angiography. In even peripheral and central areas of metastatic liver tumor, the lesions were enhanced after administration of AT-Ⅱ. CONCLUSION: These results support that high detection rate of liver metastasis revealed by pharmacoangiographic CT suggests the improvement of diagnosis on preoperative staging. Moreover, chemotherapy under AT-Ⅱ induced hypertension may have a better effect on the treatment of metastatic liver tumors.展开更多
An alternative Monte Carlo strategy for the computation of global illumination problem was presented.The proposed approach provided a new and optimal way for solving Monte Carlo global illumination based on the zero v...An alternative Monte Carlo strategy for the computation of global illumination problem was presented.The proposed approach provided a new and optimal way for solving Monte Carlo global illumination based on the zero variance importance sampling procedure. A new importance driven Monte Carlo global illumination algorithm in the framework of the new computing scheme was developed and implemented. Results, which were obtained by rendering test scenes, show that this new framework and the newly derived algorithm are effective and promising.展开更多
Peliosis hepatis(PH) is a rare benign condition characterized by the presence of multiple,randomly distributed,blood filled cystic areas of variable size within the liver parenchyma.PH is difficult to recognize and ma...Peliosis hepatis(PH) is a rare benign condition characterized by the presence of multiple,randomly distributed,blood filled cystic areas of variable size within the liver parenchyma.PH is difficult to recognize and may be mistaken for neoplasm,metastases or multiple abscesses.A 75-year-old female with a previous history of colon cancer was admitted when a liver mass in the right liver lobe was found 11 mo after surgery during the follow-up period.Computed tomography and magnetic resonance imaging scan of the abdomen were performed.The initial possible diagnosis was metastatic hepatocellular carcinoma.The patient underwent excision of the hepatic segment where the nodule was located.The pathological diagnosis of the surgical specimen was PH.PH should be considered in the differential diagnosis of new liver lesions in patients whose clinical settings do not clearly favor metastasization.Clinicians and radiologists must recognize these lesions to minimize the probability of misdiagnosis and inappropriate treatment.展开更多
With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring ba...With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring based on SECI model and information emission model. Finally customer knowledge transferring mechanism is discussed.展开更多
The Webb-Resio-Tracy(WRT) method for exact computation of the non-linear energy transfer rate was implemented in MASNUM-WAM, which is a third-generation wave model solving the discrete spectral balance equation. In th...The Webb-Resio-Tracy(WRT) method for exact computation of the non-linear energy transfer rate was implemented in MASNUM-WAM, which is a third-generation wave model solving the discrete spectral balance equation. In this paper, we describe the transformation of the spectral space in the original WRT method. Four numerical procedures were developed in which the acceleration techniques in the original WRT method, such as geometric scaling, pre-calculating, and grid-searching, are all reorganized. A series of numerical experiments including two simulations based on real data were performed. The availability of such implementation in both serial and parallel versions of the wave model was proved, and a comparison of computation times showed that some of the developed procedures provided good effi cacy. With exact computation of non-linear energy transfer, MASNUM-WAM now can be used to perform numerical experiments for research purposes, which augurs well for further developments of the model.展开更多
Phosphinoylazidation of alkenes is a direct method to build nitrogen-and phosphorus-containing compounds from feed-stock chemicals.Notwithstanding the advances in other phosphinyl radical related difunctionalization o...Phosphinoylazidation of alkenes is a direct method to build nitrogen-and phosphorus-containing compounds from feed-stock chemicals.Notwithstanding the advances in other phosphinyl radical related difunctionalization of alkenes,catalytic phosphinoylazidation of alkenes has not yet been reported.Here,we describe the first iron-catalyzed intermolecular phosphinoylazidation of styrenes and unactivated alkenes.The method is practically useful and requires a relatively low loading of catalyst.Mechanistic studies confirmed the radical nature of the reaction and disclosed the unusually low activation energy 4.8 kcal/mol of radical azido group transfer from the azidyl iron(III)phthalocyanine species(PcFeulN3)to a benzylic radical.This work may help to clarify the mechanism of iron-catalyzed azidation,inspire other mechanism studies and spur further synthetic applications.展开更多
The safety most important factor profile is one of the the plasma discharge. For limiter configuration, people usually use the following cylindrical approximation formula to calculate it q（r）=5r^2BT/RIp where r is t...The safety most important factor profile is one of the the plasma discharge. For limiter configuration, people usually use the following cylindrical approximation formula to calculate it q（r）=5r^2BT/RIp where r is the minor radius of the plasma toms, R is the major radius （in m） , BT is the toroidal magnetic field （in T）, Ip is the total toroidal current（in MA）.展开更多
Intensity of competition, especially global competition, has driven many organizations to search for innovative ways to improve productivity and performance. This trend has led many firms to adopt approaches to implem...Intensity of competition, especially global competition, has driven many organizations to search for innovative ways to improve productivity and performance. This trend has led many firms to adopt approaches to implement cloud systems. Cloud systems have distinct characteristics that differentiate it from traditional internet services, due to a number of significant innovation factors. For example, firms need improved access to high-speed intemet as well as access to customer relationship management （CRM） and enterprise resource planning （ERP） capacities. This means that the interest of many firms in the implementation of cloud systems has increased. Although cloud systems are designed to facilitate knowledge transfer, currently, there is no method to ensure that knowledge transfer is useful or relevant to a firm. This in turn means that finns need to ensure that the cloud system has the capabilities to screen knowledge for compliance against some known knowledge characteristics. The use of cloud systems could result in an efficient delivery of innovation knowledge in an effective way. This paper presents an approach for assessment of the successful implementation of cloud systems. This paper also discusses the various success factors of cloud systems for global innovation.展开更多
文摘Wide angle acquisition has been taken as a significant measure to obtain high quality seismic data and is getting greater attention, In this paper, we discuss ocean bottom cable （OBC） seismic wide angle reflections on the basis of a layered model experiment. Some experiment results don＇t support theoretical conclusions. The main experimental conclusions are： 1. Wide angle reflection energies are stronger than non-wide-angle reflections （up to twice as strong） but there is a big difference between observations and theoretical calculations that suggest the wide angle reflection energies are 15 times the non- wide-angle reflection energy. The reflection energy increases gradually rather than sharply as the theoretical calculations suggest. 2. The reflection events remain hyperbolic when the offset increases. 3. Wide angle reflection dominant frequency is about 20-30% less than non- wide-angle reflections and decreases as the offset increases. The non-wide-angle reflection dominant frequency shows no obvious variation for small offsets. 4. There is no wave shape mutation or polarity reversal near the critical angle. 5. The reflection event group features are the same for both cases of incidence angle greater and less than the critical angle. 6. Direct arrivals, multiples, and water bottom refractions influence the wide angle reflections of the sea floor.
文摘Under the method of density functional theory, the geometry structures, values of energy and population analysis of the combo of crown tetraalanylpeptide （C4-AIa） with ions （Xn） are calculated, based on the foundation of former studies. It was found that the coronary structure changed little whether in C4-Ala or C4-Ala-Xn, and the electrons transferred between C4-Ala and Xn at the mean time. There were coordinate bonds between Xn＋ and the nitrogen from -NH-, hydrogen bonds between Xa and the hydrogen from -NH-, and they became weaker when the radii of ions turned larger. Besides, the values of the single point bonding energy fluctuated gradually as a shape of saddle, but cations and anions located in opposite directions of the center of coronary structure when reach minimum, respectively.
文摘AIM: To analyze the imaging findings of hepatic malignancy with right atrial (RA) embolus. METHODS: Forty-six patients with an embolus in the RA were diagnosed, including 44 patients with hepatocellular carcinoma (HCC), 1 patient with cholangiocellular carcinoma and 1 patient with hepatic carcinoma metastasis. The diagnosis was confirmed by clinical examination, serum α-fetoprotein and imaging. Seventeen patients underwent transcatheter arterial chemoembolization (TACE). RESULTS: On enhancement computer tomography (CT) or magnetic resonance (MR) imaging, a nodular filling defect in the RA could be easily found, with a slight enhancement in the arterial phase. The coronal images of CT or MR showed the extent of lesion. Lipiodol entered the embolus after TACE, hence reducing the speed of embolus growth. There was a survival benefit for patients receiving anticancer treatment. CONCLUSION: Patients with HCC, showing a filling defect of the inferior vena cava (IVC), hepatic vein (HV) and RA on images, can be diagnosed with RA embolus. Encroachment of the RA is very rare in patients with hepatic malignancies. Furthermore, a prolongation of survival time is found in those patients who underwent TACE.
基金the National High-tech R&D Program ("863" Program) of China，the National Science Foundation of China，National Science & Technology Pillar Program of China，the National Science Foundation of China，the Post-Doctoral Funding of China，Tsinghua-Huawei joint research project
文摘In order to improve the scalability and reliability of Software Defined Networking(SDN),many studies use multiple controllers to constitute logically centralized control plane to provide load balancing and fail over.In this paper,we develop a flexible dormant multi-controller model based on the centralized multi-controller architecture.The dormant multi-controller model allows part of controllers to enter the dormant state under light traffic condition for saving system cost.Meanwhile,through queueing analysis,various performance measures of the system can be obtained.Moreover,we analyze the real traffic of China Education Network and use the results as the parameters of computer simulation and verify the effects of parameters on the system characteristics.Finally,a total expected cost function is established,and genetic algorithm is employed to find the optimal values of various parameters to minimize system cost for the deployment decision making.
文摘AIM: To improve the preoperative diagnosis of liver metastasis from pancreatic cancer, we estimated computed tomography during arterial angiography (CTA) with/without administration of angiotensin-Ⅱ (AT-Ⅱ). METHODS: Thirty-fi ve patients with pancreatic cancer were examined in this study. After conventional CTA was performed, pharmacoangiographic CTA was performed with a 1-3 microgram/5 mL solution of angiotensin Ⅱ injected through a catheter into the celiac artery during spiral computed tomography. We prospectively analyzed the relative region of interest (ROI) ratio of tumor to liver with/without AT-Ⅱ. RESULTS: In all patients, the relative ratio of each computed tomography (CT) number in the ROI was larger at pharmacoangiographic CT than at conventional angiographic CT. Administration of angiotensin-Ⅱ enhanced the metastatic liver tumor as compared with normal tissue. Intratumoral blood flow increased in all patients with malignant tumors due to the pressure effect of AT-Ⅱ. Furthermore, the metastatic lesions in the liver of three patients were represented by only pharmacoangiographic CT, not by conventional CT and conventional CT angiography. In even peripheral and central areas of metastatic liver tumor, the lesions were enhanced after administration of AT-Ⅱ. CONCLUSION: These results support that high detection rate of liver metastasis revealed by pharmacoangiographic CT suggests the improvement of diagnosis on preoperative staging. Moreover, chemotherapy under AT-Ⅱ induced hypertension may have a better effect on the treatment of metastatic liver tumors.
文摘An alternative Monte Carlo strategy for the computation of global illumination problem was presented.The proposed approach provided a new and optimal way for solving Monte Carlo global illumination based on the zero variance importance sampling procedure. A new importance driven Monte Carlo global illumination algorithm in the framework of the new computing scheme was developed and implemented. Results, which were obtained by rendering test scenes, show that this new framework and the newly derived algorithm are effective and promising.
文摘Peliosis hepatis(PH) is a rare benign condition characterized by the presence of multiple,randomly distributed,blood filled cystic areas of variable size within the liver parenchyma.PH is difficult to recognize and may be mistaken for neoplasm,metastases or multiple abscesses.A 75-year-old female with a previous history of colon cancer was admitted when a liver mass in the right liver lobe was found 11 mo after surgery during the follow-up period.Computed tomography and magnetic resonance imaging scan of the abdomen were performed.The initial possible diagnosis was metastatic hepatocellular carcinoma.The patient underwent excision of the hepatic segment where the nodule was located.The pathological diagnosis of the surgical specimen was PH.PH should be considered in the differential diagnosis of new liver lesions in patients whose clinical settings do not clearly favor metastasization.Clinicians and radiologists must recognize these lesions to minimize the probability of misdiagnosis and inappropriate treatment.
文摘With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring based on SECI model and information emission model. Finally customer knowledge transferring mechanism is discussed.
基金Supported by the State Oceanic Administration Marine Science Foundation for Young Scientists(Nos.2012245,2012249)
文摘The Webb-Resio-Tracy(WRT) method for exact computation of the non-linear energy transfer rate was implemented in MASNUM-WAM, which is a third-generation wave model solving the discrete spectral balance equation. In this paper, we describe the transformation of the spectral space in the original WRT method. Four numerical procedures were developed in which the acceleration techniques in the original WRT method, such as geometric scaling, pre-calculating, and grid-searching, are all reorganized. A series of numerical experiments including two simulations based on real data were performed. The availability of such implementation in both serial and parallel versions of the wave model was proved, and a comparison of computation times showed that some of the developed procedures provided good effi cacy. With exact computation of non-linear energy transfer, MASNUM-WAM now can be used to perform numerical experiments for research purposes, which augurs well for further developments of the model.
文摘Phosphinoylazidation of alkenes is a direct method to build nitrogen-and phosphorus-containing compounds from feed-stock chemicals.Notwithstanding the advances in other phosphinyl radical related difunctionalization of alkenes,catalytic phosphinoylazidation of alkenes has not yet been reported.Here,we describe the first iron-catalyzed intermolecular phosphinoylazidation of styrenes and unactivated alkenes.The method is practically useful and requires a relatively low loading of catalyst.Mechanistic studies confirmed the radical nature of the reaction and disclosed the unusually low activation energy 4.8 kcal/mol of radical azido group transfer from the azidyl iron(III)phthalocyanine species(PcFeulN3)to a benzylic radical.This work may help to clarify the mechanism of iron-catalyzed azidation,inspire other mechanism studies and spur further synthetic applications.
文摘The safety most important factor profile is one of the the plasma discharge. For limiter configuration, people usually use the following cylindrical approximation formula to calculate it q（r）=5r^2BT/RIp where r is the minor radius of the plasma toms, R is the major radius （in m） , BT is the toroidal magnetic field （in T）, Ip is the total toroidal current（in MA）.
文摘Intensity of competition, especially global competition, has driven many organizations to search for innovative ways to improve productivity and performance. This trend has led many firms to adopt approaches to implement cloud systems. Cloud systems have distinct characteristics that differentiate it from traditional internet services, due to a number of significant innovation factors. For example, firms need improved access to high-speed intemet as well as access to customer relationship management （CRM） and enterprise resource planning （ERP） capacities. This means that the interest of many firms in the implementation of cloud systems has increased. Although cloud systems are designed to facilitate knowledge transfer, currently, there is no method to ensure that knowledge transfer is useful or relevant to a firm. This in turn means that finns need to ensure that the cloud system has the capabilities to screen knowledge for compliance against some known knowledge characteristics. The use of cloud systems could result in an efficient delivery of innovation knowledge in an effective way. This paper presents an approach for assessment of the successful implementation of cloud systems. This paper also discusses the various success factors of cloud systems for global innovation.
