Hue-Saturation-Intensity (HSI) color model, a psychologically appealing color model, was employed to visualize uncertainty represented by relative prediction error based on the case of spatial prediction of pH of to...Hue-Saturation-Intensity (HSI) color model, a psychologically appealing color model, was employed to visualize uncertainty represented by relative prediction error based on the case of spatial prediction of pH of topsoil in the peri-urban Beijing. A two-dimensional legend was designed to accompany the visualization-vertical axis (hues) for visualizing the predicted values and horizontal axis (whiteness) for visualizing the prediction error. Moreover, different ways of visualizing uncertainty were briefly reviewed in this paper. This case study indicated that visualization of both predictions and prediction uncertainty offered a possibility to enhance visual exploration of the data uncertainty and to compare different prediction methods or predictions of totally different variables. The whitish region of the visualization map can be simply interpreted as unsatisfactory prediction results, where may need additional samples or more suitable prediction models for a better prediction results.展开更多
This paper elaborated the special geological conditions of Chongqing City and the characteristics of urban bridges formed by natural environment, and put forth the ecological landscape design ideas of urban bridges. 3...This paper elaborated the special geological conditions of Chongqing City and the characteristics of urban bridges formed by natural environment, and put forth the ecological landscape design ideas of urban bridges. 3 principles of ecological landscape design were presented including paying attention to the creation of great environment, focusing on the comparison and harmony between natural and artificial factors and seeking for simple lines and unified colors, and the application of ecological landscape design principles in constructing ecological landscape of bridges in Chongqing City was analyzed. By discussing the existing problems of ecological landscape design of bridges in Chongqing City, some suggestions were summarized, which were expected to produce positive effects for the researches of ecological landscape design of bridges.展开更多
Tidal data of Tanggu marine environment monitoring stations for 59 years (1950-2008) was processed by using harmonic analysis, harmonic constants curves were discussed. And by using FFT spectral analysis periodicity...Tidal data of Tanggu marine environment monitoring stations for 59 years (1950-2008) was processed by using harmonic analysis, harmonic constants curves were discussed. And by using FFT spectral analysis periodicity and causation of its harmonic constants were analyzed. Alter astronomic tide signal was eliminated, residual water level was decomposed by using FFT spectral analysis, and then we got the periodic variation of mean residual water level over the past 50 years and discussed mean sea level changing trends of Tianjin offshore. The results show that variety of amplitude of M2 tidal constituent reveals 20 years, 4-6 years, 2-3-year periods, and it was obviously influenced by engineering construction since reform and opening age. Residual water level fluctuations reveal 20 years, 5-6 years, 2-3 years and 1 year periods. Sea level of Tianjin offshore displays a progressive ascending trend with rate about 3.4mm/a, which was influenced mainly by sea level rise and land subsidence.展开更多
Let u(z) be a real_valued harmonic function in the unit disk, we say u(z)∈h p(1【p【+∞), if the p _mean M p(r,u)=12π∫ 2π 0|u(re i θ )| p d θ 1/p is bounded. M.Riesz showed ...Let u(z) be a real_valued harmonic function in the unit disk, we say u(z)∈h p(1【p【+∞), if the p _mean M p(r,u)=12π∫ 2π 0|u(re i θ )| p d θ 1/p is bounded. M.Riesz showed that if u(z)∈h p(1【p【+∞), then there exists a constant A p, depending only on p such that M p(r,v)≤A pM p(r,u), where v(z) is the conjugate harmonic function of u(z).When v(0)=0 and 1【p≤2, W.K.Hayman showed that A p can be given by pp-1 1/p . First, this paper shows that the constant pp-1 1/p can be changed by a smaller constant pp-1 2/p -1 1/2 . Next, if 1【p≤2, then there exists a constant θ 0∈2-p2pπ,π2p such that M p p(r,v)≤ Im p sin pπ2+ tg pπ2pM p p(r,u) for any analytic function f(z)=u(z)+ i v(z) in the unit disk, whenever -θ 0【 arg f(z)【π2.展开更多
The biharmonicity of the product map Φ2=φ×ψ and the two generalized projections φ-and ψ-are analyzed. Some results are obtained, that is, Φ2 is a proper biharmonic map if and only if b is a non-constant sol...The biharmonicity of the product map Φ2=φ×ψ and the two generalized projections φ-and ψ-are analyzed. Some results are obtained, that is, Φ2 is a proper biharmonic map if and only if b is a non-constant solution of -1/f2 Jφ(dφ(grad(lnb)))+n/2 grad|dφ(grad(lnb))|2=0 and f is a non-constant solution of -1/b2Jψ(dψ(grad(lnf)))+m/2grad|dψ(grad(lnf))|2=0, and Φ2=φ×ψ is a proper biharmonic map if and only if φ-and ψ-are proper biharmonic maps.展开更多
It aims to draw the conclusion that the ideas of treatment in Zhen Jiu Jia Yi Jing (《针灸甲乙经》, A-B Classic on Acupuncture and Moxibustion ) can be summarized as "regulation" and "harmonization" through the ...It aims to draw the conclusion that the ideas of treatment in Zhen Jiu Jia Yi Jing (《针灸甲乙经》, A-B Classic on Acupuncture and Moxibustion ) can be summarized as "regulation" and "harmonization" through the research of words in the Classic, such as "being normal", "regulation" and "harmonization". The lost of regulation of a normal person shows disharmony. Regulation can make the person-being-sick become harmony and back to "being normal". "Regulation" and "harmonization" right imply the quintessence of traditional Chinese medicine.展开更多
The textural features and acidic properties of sulfated mesoporous lanthana‐zirconia solid acids (SO42?/meso‐La0.1Zr0.9Oδ) were efficiently tuned by modifying the conditions used to prepare the meso‐La0.1Zr0.9O...The textural features and acidic properties of sulfated mesoporous lanthana‐zirconia solid acids (SO42?/meso‐La0.1Zr0.9Oδ) were efficiently tuned by modifying the conditions used to prepare the meso‐La0.1Zr0.9Oδcomposites, such as the molar ratio of the template to La and Zr metal ions (Nt/m), molar ratio of ammonia to La and Zr metal ions (Na/m), hydrothermal temperature (Thydro), and hy‐drothermal time (thydro). The effect of the textural features and acidic properties on the catalytic performance of solid acid catalysts for alkenylation of p‐xylene with phenylacetylene was investi‐gated. Various characterization techniques such as N2 physisorption, X‐ray diffraction, NH3 temper‐ature‐programmed desorption, and thermogravimetric analysis were employed to reveal the rela‐tionship between the nature of catalyst and its catalytic performance. It was found that the catalytic performance significantly depended on the textural features and acidic properties, which were strongly affected by preparation conditions of the meso‐La0.1Zr0.9Oδcomposite. Appropriate acidic sites and high accessibility were required to obtain satisfactory catalytic reactions for this reaction. It was also found that the average crystallite size of t‐ZrO2 affected by the preparation conditions had significant influence on the ultrastrong acidic sites of the catalysts. The optimized SO42?/meso‐La0.1Zr0.9Oδcatalyst exhibited much superior catalytic activity and coke‐resistant stabil‐ity. Moreover, the developed SO42?/meso‐La0.1Zr0.9Oδcatalyst demonstrated excellent catalytic per‐formance for alkenylation of diverse aromatics with phenylacetylene to their correspondingα‐arylstyrenes. Combining the previously established complete regeneration of used catalysts by a facile calcination process with the improved catalytic properties, the developed SO42?/meso‐La0.1Zr0.9Oδ solid acid could be a potential catalyst for industrial production ofα‐arylstyrenes through clean and atom efficient solid‐acid‐mediated Friedel‐Crafts alkenylation of diverse aromatics with phenylacetylene.展开更多
Application of herbal medicine to acupoints is to regulate the meridians, yin-yang, and qi and blood for preventing and treating diseases through the pharmacological action of herbal medicines and with their stimulati...Application of herbal medicine to acupoints is to regulate the meridians, yin-yang, and qi and blood for preventing and treating diseases through the pharmacological action of herbal medicines and with their stimulation to the acupoints. This article explains how to apply herbal medicines and gave the examples for the treatment of hypertension, asthma, chronic bronchitis and allergic rhinitis. Application of herbal medicines to acupoints is one of the important components of TCM, which shows satisfactory effects in treatment of some chronic diseases.展开更多
The bystin-like (BYSL) gene was previously characterized to encode an accessory protein for cell adhesion that participates in early embryo implantation. It is also involved in 40S ribosomal subunit biogenesis and i...The bystin-like (BYSL) gene was previously characterized to encode an accessory protein for cell adhesion that participates in early embryo implantation. It is also involved in 40S ribosomal subunit biogenesis and is found to be expressed in rapidly growing embryo and cancer cell lines. In order to explore the role of BYSL in cancer cell proliferation and growth, we used hepatocellular carcinoma (HCC) as a model. Here, we report that BYSL is crucial for HCC cell growth both in vitro and in vivo. Expression levels of BYSL mRNA and protein in human HCC specimens were markedly increased compared with those seen in adjacent non-cancerous tissue. In vitro, inhibition of BYSL by short hairpin RNA decreased HCC cell proliferation, induced apoptosis and partially arrested the cell cycle in the G2/M phase. In vivo, HCC cells treated with BYSL siRNA failed to form tumors in nude mice after subcutaneous implantation. To determine the cellular basis for BYSL RNAi-induced cell growth arrest, BYSL subcellular localization in mitotic and interphase HepG2 cells was examined. BYSL was present at multiple stages during nucleologenesis, including in nucleolus-derived foci (NDF), perichromosomal regions and the prenucleolar body (PNB) during mitosis. BYSL depletion remarkably suppressed NDF and PNB formation, and disrupted nucleoli assembly after mitosis, resulting in increased apoptosis and reduced tolerance of HCC cells to serum starvation. Taken together, our studies indicate that upregulated BYSL expression plays a role in hepatocarcinogenesis.展开更多
The new method which uses the consensus algorithm to solve the coordinate control problems of multiple unmanned underwater vehicles (multi-UUVs) formation in the case of leader-following is adapted. As the communica...The new method which uses the consensus algorithm to solve the coordinate control problems of multiple unmanned underwater vehicles (multi-UUVs) formation in the case of leader-following is adapted. As the communication between the UUVs is difficult and it is easy to be interfered under the water, time delay is assumed to be time-varying during the members communicate with each other. Meanwhile, the state feedback linearization method is used to transfer the nonlinear and coupling model of UUV into double-integrator dynamic. With this simplified double-integrator math model, the UUV formation coordinate control is regarded as consensus problem with time-varying communication delays. In addition, the position and velocity topologies are adapted to reduce the data volume in each data packet which is sent between members in formation. With two independent topologies designed, two cases of communication delay which are same and different are considered and the sufficient conditions are proposed and analyzed. The stability of the multi-UUVs formation is proven by using Lyapunov-Razumilkhin theorem. Finally, the simulation results are presented to confirm and illustrate the theoretical results.展开更多
AIM:To review safety,efficacy,and proper nursing care of double-balloon enteroscopy (DBE) in pediatric patients with small intestinal disease.METHODS:Our study included 37 patients with abdominal pain,diarrhea,passage...AIM:To review safety,efficacy,and proper nursing care of double-balloon enteroscopy (DBE) in pediatric patients with small intestinal disease.METHODS:Our study included 37 patients with abdominal pain,diarrhea,passage of blood in the stools,and other symptoms,who underwent DBE from December 2006 to July 2010.DBE was retrograde in 36 procedures,antegrade in six,and from both ends in five.The diagnostic significance and salient points in nursing care are discussed in this article.RESULTS:At least one lesion was discovered in 28 out of 37 patients,which yielded a positive diagnosis in 75.7% of cases.Good bowel preparation and skilled nursing care not only shortened the procedure time,but could also alleviate patient discomfort and enhance the quality of examination.No serious procedure-related complications were observed in any cases.CONCLUSION:DBE is a new modality of endoscopic procedure that improves the standard of diagnosis and treatment of small bowel diseases in children.Good nursing care is essential to the successful execution of the procedure.展开更多
The problem of spherical parametrization is that of mapping a genus-zero mesh onto a spherical surface. For a given mesh, different parametrizations can be obtained by different methods. And for a certain application,...The problem of spherical parametrization is that of mapping a genus-zero mesh onto a spherical surface. For a given mesh, different parametrizations can be obtained by different methods. And for a certain application, some parametrization results might behave better than others. In this paper, we will propose a method to parametrize a genus-zero mesh so that a surface fitting algorithm with PHT-splines can generate good result. Here the parametrization results are obtained by minimizing discrete har- monic energy subject to spherical constraints. Then some applications are given to illustrate the advantages of our results. Based on PHT-splines, parametric surfaces can be constructed efficiently and adaptively to fit genus-zero meshes after their spherical parametrization has been obtained.展开更多
Coordination technology addresses the construction of open, flexible systems from active and independent software agents in concurrent and distributed systems. In most open distributed applications, multiple agents ne...Coordination technology addresses the construction of open, flexible systems from active and independent software agents in concurrent and distributed systems. In most open distributed applications, multiple agents need interaction and communication to achieve their overall goal. Coordination technologies for the Internet typically are concerned with enabling interaction among agents and helping them cooperate with each other. At the same time, access control should also be considered to constrain interaction to make it harmless. Access control should be regarded as the security counterpart of coordination. At present, the combination of coordination and access control remains an open problem. Thus, we propose a role Dased coordination model with policy enforcement in agent application systems. In this model, coordination is combined with access control so as to fully characterize the interactions in agent systems. A set of agents interacting with each other for a common global system task constitutes a coordination group. Role based access control is applied in this model to prevent unauthorized accesses. Coordination policy is enforced in a distributed manner so that the model can be applied to the open distributed systems such as Internet. An Internet online auction system is presented as a case study to illustrate the proposed coordination model and finally the performance analysis of the model is introduced.展开更多
To determine the procedure-related factors that affect sedation satisfaction and to make a suggestion to improve it.METHODSWe prospectively enrolled a total of 456 patients who underwent outpatient endoscopy procedure...To determine the procedure-related factors that affect sedation satisfaction and to make a suggestion to improve it.METHODSWe prospectively enrolled a total of 456 patients who underwent outpatient endoscopy procedures with midazolam sedation between March 2014 and August 2014. All patients completed both pre- and post-endoscopy questionnaires about sedation expectations and satisfaction.RESULTSThe study cohort included 167 (36.6%) patients who underwent esophagogastroduodenoscopy (EGD), 167 (36.6%) who underwent colonoscopy, and 122 (26.8%) who underwent a combined procedure (EGD and colonoscopy). Over 80% of all patients were satisfied with sedation using midazolam. In univariate and multivariate analyses, total procedure time in the EGD group, younger age (≤ 50 years), and longer colonoscopy withdrawal time in the colonoscopy group were related to decreased satisfaction with sedation. However, in active monitoring and intervention group, there was no decrease in grade of satisfaction despite longer procedure time due to more procedures during colonoscopy. Younger age (≤ 50 years), longer inter-procedure time gap, and colonoscopy withdrawal time were related to decreased satisfaction in the combined EGD and colonoscopy group.CONCLUSIONMidazolam is still a safe and effective sedative for gastrointestinal endoscopy. Satisfaction with sedation depends on several factors including age (≤ 50 years) and procedure time duration. To improve patient satisfaction with sedation, active monitoring of sedation status by the endoscopist should be considered for patients who require long procedure time.展开更多
In this paper,a generalized Laguerre-spherical harmonic spectral method is proposed for the Cauchy problem of three-dimensional nonlinear Klein-Gordon equation. The goal is to make the numerical solutions to preserve ...In this paper,a generalized Laguerre-spherical harmonic spectral method is proposed for the Cauchy problem of three-dimensional nonlinear Klein-Gordon equation. The goal is to make the numerical solutions to preserve the same conservation as that for the exact solution.The stability and convergence of the proposed scheme are proved.Numerical results demonstrate the efficiency of this approach.We also establish some basic results on the generalized Laguerre-spherical harmonic orthogonal approximation,which play an important role in spectral methods for various problems defined on the whole space and unbounded domains with spherical geometry.展开更多
基金Under the auspices of Knowledge Innovation Frontier Project of Institute of Soil Science,Chinese Academy of Sciences(No.ISSASIP0716 )the National Nature Science Foundation of China ( No.40701070,40571065)
文摘Hue-Saturation-Intensity (HSI) color model, a psychologically appealing color model, was employed to visualize uncertainty represented by relative prediction error based on the case of spatial prediction of pH of topsoil in the peri-urban Beijing. A two-dimensional legend was designed to accompany the visualization-vertical axis (hues) for visualizing the predicted values and horizontal axis (whiteness) for visualizing the prediction error. Moreover, different ways of visualizing uncertainty were briefly reviewed in this paper. This case study indicated that visualization of both predictions and prediction uncertainty offered a possibility to enhance visual exploration of the data uncertainty and to compare different prediction methods or predictions of totally different variables. The whitish region of the visualization map can be simply interpreted as unsatisfactory prediction results, where may need additional samples or more suitable prediction models for a better prediction results.
文摘This paper elaborated the special geological conditions of Chongqing City and the characteristics of urban bridges formed by natural environment, and put forth the ecological landscape design ideas of urban bridges. 3 principles of ecological landscape design were presented including paying attention to the creation of great environment, focusing on the comparison and harmony between natural and artificial factors and seeking for simple lines and unified colors, and the application of ecological landscape design principles in constructing ecological landscape of bridges in Chongqing City was analyzed. By discussing the existing problems of ecological landscape design of bridges in Chongqing City, some suggestions were summarized, which were expected to produce positive effects for the researches of ecological landscape design of bridges.
文摘Tidal data of Tanggu marine environment monitoring stations for 59 years (1950-2008) was processed by using harmonic analysis, harmonic constants curves were discussed. And by using FFT spectral analysis periodicity and causation of its harmonic constants were analyzed. Alter astronomic tide signal was eliminated, residual water level was decomposed by using FFT spectral analysis, and then we got the periodic variation of mean residual water level over the past 50 years and discussed mean sea level changing trends of Tianjin offshore. The results show that variety of amplitude of M2 tidal constituent reveals 20 years, 4-6 years, 2-3-year periods, and it was obviously influenced by engineering construction since reform and opening age. Residual water level fluctuations reveal 20 years, 5-6 years, 2-3 years and 1 year periods. Sea level of Tianjin offshore displays a progressive ascending trend with rate about 3.4mm/a, which was influenced mainly by sea level rise and land subsidence.
文摘Let u(z) be a real_valued harmonic function in the unit disk, we say u(z)∈h p(1【p【+∞), if the p _mean M p(r,u)=12π∫ 2π 0|u(re i θ )| p d θ 1/p is bounded. M.Riesz showed that if u(z)∈h p(1【p【+∞), then there exists a constant A p, depending only on p such that M p(r,v)≤A pM p(r,u), where v(z) is the conjugate harmonic function of u(z).When v(0)=0 and 1【p≤2, W.K.Hayman showed that A p can be given by pp-1 1/p . First, this paper shows that the constant pp-1 1/p can be changed by a smaller constant pp-1 2/p -1 1/2 . Next, if 1【p≤2, then there exists a constant θ 0∈2-p2pπ,π2p such that M p p(r,v)≤ Im p sin pπ2+ tg pπ2pM p p(r,u) for any analytic function f(z)=u(z)+ i v(z) in the unit disk, whenever -θ 0【 arg f(z)【π2.
基金The National Natural Science Foundation of China(No.10971029)
文摘The biharmonicity of the product map Φ2=φ×ψ and the two generalized projections φ-and ψ-are analyzed. Some results are obtained, that is, Φ2 is a proper biharmonic map if and only if b is a non-constant solution of -1/f2 Jφ(dφ(grad(lnb)))+n/2 grad|dφ(grad(lnb))|2=0 and f is a non-constant solution of -1/b2Jψ(dψ(grad(lnf)))+m/2grad|dψ(grad(lnf))|2=0, and Φ2=φ×ψ is a proper biharmonic map if and only if φ-and ψ-are proper biharmonic maps.
文摘It aims to draw the conclusion that the ideas of treatment in Zhen Jiu Jia Yi Jing (《针灸甲乙经》, A-B Classic on Acupuncture and Moxibustion ) can be summarized as "regulation" and "harmonization" through the research of words in the Classic, such as "being normal", "regulation" and "harmonization". The lost of regulation of a normal person shows disharmony. Regulation can make the person-being-sick become harmony and back to "being normal". "Regulation" and "harmonization" right imply the quintessence of traditional Chinese medicine.
基金financially supported by the National Natural Science Foundation of China (21276041)the Program for New Century Excellent Talents in University of Ministry of Education (NCET-12-0079)+1 种基金the Natural Science Foundation of Liaoning Province (2015020200)the Fundamental Research Funds for the Central Universities (DUT15LK41)~~
文摘The textural features and acidic properties of sulfated mesoporous lanthana‐zirconia solid acids (SO42?/meso‐La0.1Zr0.9Oδ) were efficiently tuned by modifying the conditions used to prepare the meso‐La0.1Zr0.9Oδcomposites, such as the molar ratio of the template to La and Zr metal ions (Nt/m), molar ratio of ammonia to La and Zr metal ions (Na/m), hydrothermal temperature (Thydro), and hy‐drothermal time (thydro). The effect of the textural features and acidic properties on the catalytic performance of solid acid catalysts for alkenylation of p‐xylene with phenylacetylene was investi‐gated. Various characterization techniques such as N2 physisorption, X‐ray diffraction, NH3 temper‐ature‐programmed desorption, and thermogravimetric analysis were employed to reveal the rela‐tionship between the nature of catalyst and its catalytic performance. It was found that the catalytic performance significantly depended on the textural features and acidic properties, which were strongly affected by preparation conditions of the meso‐La0.1Zr0.9Oδcomposite. Appropriate acidic sites and high accessibility were required to obtain satisfactory catalytic reactions for this reaction. It was also found that the average crystallite size of t‐ZrO2 affected by the preparation conditions had significant influence on the ultrastrong acidic sites of the catalysts. The optimized SO42?/meso‐La0.1Zr0.9Oδcatalyst exhibited much superior catalytic activity and coke‐resistant stabil‐ity. Moreover, the developed SO42?/meso‐La0.1Zr0.9Oδcatalyst demonstrated excellent catalytic per‐formance for alkenylation of diverse aromatics with phenylacetylene to their correspondingα‐arylstyrenes. Combining the previously established complete regeneration of used catalysts by a facile calcination process with the improved catalytic properties, the developed SO42?/meso‐La0.1Zr0.9Oδ solid acid could be a potential catalyst for industrial production ofα‐arylstyrenes through clean and atom efficient solid‐acid‐mediated Friedel‐Crafts alkenylation of diverse aromatics with phenylacetylene.
文摘Application of herbal medicine to acupoints is to regulate the meridians, yin-yang, and qi and blood for preventing and treating diseases through the pharmacological action of herbal medicines and with their stimulation to the acupoints. This article explains how to apply herbal medicines and gave the examples for the treatment of hypertension, asthma, chronic bronchitis and allergic rhinitis. Application of herbal medicines to acupoints is one of the important components of TCM, which shows satisfactory effects in treatment of some chronic diseases.
文摘The bystin-like (BYSL) gene was previously characterized to encode an accessory protein for cell adhesion that participates in early embryo implantation. It is also involved in 40S ribosomal subunit biogenesis and is found to be expressed in rapidly growing embryo and cancer cell lines. In order to explore the role of BYSL in cancer cell proliferation and growth, we used hepatocellular carcinoma (HCC) as a model. Here, we report that BYSL is crucial for HCC cell growth both in vitro and in vivo. Expression levels of BYSL mRNA and protein in human HCC specimens were markedly increased compared with those seen in adjacent non-cancerous tissue. In vitro, inhibition of BYSL by short hairpin RNA decreased HCC cell proliferation, induced apoptosis and partially arrested the cell cycle in the G2/M phase. In vivo, HCC cells treated with BYSL siRNA failed to form tumors in nude mice after subcutaneous implantation. To determine the cellular basis for BYSL RNAi-induced cell growth arrest, BYSL subcellular localization in mitotic and interphase HepG2 cells was examined. BYSL was present at multiple stages during nucleologenesis, including in nucleolus-derived foci (NDF), perichromosomal regions and the prenucleolar body (PNB) during mitosis. BYSL depletion remarkably suppressed NDF and PNB formation, and disrupted nucleoli assembly after mitosis, resulting in increased apoptosis and reduced tolerance of HCC cells to serum starvation. Taken together, our studies indicate that upregulated BYSL expression plays a role in hepatocarcinogenesis.
基金Projects(51309067,51679057,51609048)supported by the National Natural Science Foundation of ChinaProject(JC2016007)supported by the Outstanding Youth Science Foundation of Heilongjiang Province,ChinaProject(HEUCFX041401)supported by the Fundamental Research Funds for the Central Universities,China
文摘The new method which uses the consensus algorithm to solve the coordinate control problems of multiple unmanned underwater vehicles (multi-UUVs) formation in the case of leader-following is adapted. As the communication between the UUVs is difficult and it is easy to be interfered under the water, time delay is assumed to be time-varying during the members communicate with each other. Meanwhile, the state feedback linearization method is used to transfer the nonlinear and coupling model of UUV into double-integrator dynamic. With this simplified double-integrator math model, the UUV formation coordinate control is regarded as consensus problem with time-varying communication delays. In addition, the position and velocity topologies are adapted to reduce the data volume in each data packet which is sent between members in formation. With two independent topologies designed, two cases of communication delay which are same and different are considered and the sufficient conditions are proposed and analyzed. The stability of the multi-UUVs formation is proven by using Lyapunov-Razumilkhin theorem. Finally, the simulation results are presented to confirm and illustrate the theoretical results.
文摘AIM:To review safety,efficacy,and proper nursing care of double-balloon enteroscopy (DBE) in pediatric patients with small intestinal disease.METHODS:Our study included 37 patients with abdominal pain,diarrhea,passage of blood in the stools,and other symptoms,who underwent DBE from December 2006 to July 2010.DBE was retrograde in 36 procedures,antegrade in six,and from both ends in five.The diagnostic significance and salient points in nursing care are discussed in this article.RESULTS:At least one lesion was discovered in 28 out of 37 patients,which yielded a positive diagnosis in 75.7% of cases.Good bowel preparation and skilled nursing care not only shortened the procedure time,but could also alleviate patient discomfort and enhance the quality of examination.No serious procedure-related complications were observed in any cases.CONCLUSION:DBE is a new modality of endoscopic procedure that improves the standard of diagnosis and treatment of small bowel diseases in children.Good nursing care is essential to the successful execution of the procedure.
基金Project supported by the Outstanding Youth Grant of Natural Science Foundation of China (No. 60225002), the National Basic Research Program (973) of China (No. 2004CB318000), the National Natural Science Foundation of China (Nos. 60533060 and 60473132)
文摘The problem of spherical parametrization is that of mapping a genus-zero mesh onto a spherical surface. For a given mesh, different parametrizations can be obtained by different methods. And for a certain application, some parametrization results might behave better than others. In this paper, we will propose a method to parametrize a genus-zero mesh so that a surface fitting algorithm with PHT-splines can generate good result. Here the parametrization results are obtained by minimizing discrete har- monic energy subject to spherical constraints. Then some applications are given to illustrate the advantages of our results. Based on PHT-splines, parametric surfaces can be constructed efficiently and adaptively to fit genus-zero meshes after their spherical parametrization has been obtained.
文摘Coordination technology addresses the construction of open, flexible systems from active and independent software agents in concurrent and distributed systems. In most open distributed applications, multiple agents need interaction and communication to achieve their overall goal. Coordination technologies for the Internet typically are concerned with enabling interaction among agents and helping them cooperate with each other. At the same time, access control should also be considered to constrain interaction to make it harmless. Access control should be regarded as the security counterpart of coordination. At present, the combination of coordination and access control remains an open problem. Thus, we propose a role Dased coordination model with policy enforcement in agent application systems. In this model, coordination is combined with access control so as to fully characterize the interactions in agent systems. A set of agents interacting with each other for a common global system task constitutes a coordination group. Role based access control is applied in this model to prevent unauthorized accesses. Coordination policy is enforced in a distributed manner so that the model can be applied to the open distributed systems such as Internet. An Internet online auction system is presented as a case study to illustrate the proposed coordination model and finally the performance analysis of the model is introduced.
文摘To determine the procedure-related factors that affect sedation satisfaction and to make a suggestion to improve it.METHODSWe prospectively enrolled a total of 456 patients who underwent outpatient endoscopy procedures with midazolam sedation between March 2014 and August 2014. All patients completed both pre- and post-endoscopy questionnaires about sedation expectations and satisfaction.RESULTSThe study cohort included 167 (36.6%) patients who underwent esophagogastroduodenoscopy (EGD), 167 (36.6%) who underwent colonoscopy, and 122 (26.8%) who underwent a combined procedure (EGD and colonoscopy). Over 80% of all patients were satisfied with sedation using midazolam. In univariate and multivariate analyses, total procedure time in the EGD group, younger age (≤ 50 years), and longer colonoscopy withdrawal time in the colonoscopy group were related to decreased satisfaction with sedation. However, in active monitoring and intervention group, there was no decrease in grade of satisfaction despite longer procedure time due to more procedures during colonoscopy. Younger age (≤ 50 years), longer inter-procedure time gap, and colonoscopy withdrawal time were related to decreased satisfaction in the combined EGD and colonoscopy group.CONCLUSIONMidazolam is still a safe and effective sedative for gastrointestinal endoscopy. Satisfaction with sedation depends on several factors including age (≤ 50 years) and procedure time duration. To improve patient satisfaction with sedation, active monitoring of sedation status by the endoscopist should be considered for patients who require long procedure time.
基金supported in part by NSF of China N.10871131The Science and Technology Commission of Shanghai Municipality,Grant N.075105118+1 种基金Shanghai Leading Academic Discipline Project N.T0401Fund for E-institute of Shanghai Universities N.E03004.
文摘In this paper,a generalized Laguerre-spherical harmonic spectral method is proposed for the Cauchy problem of three-dimensional nonlinear Klein-Gordon equation. The goal is to make the numerical solutions to preserve the same conservation as that for the exact solution.The stability and convergence of the proposed scheme are proved.Numerical results demonstrate the efficiency of this approach.We also establish some basic results on the generalized Laguerre-spherical harmonic orthogonal approximation,which play an important role in spectral methods for various problems defined on the whole space and unbounded domains with spherical geometry.