A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distr...A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distribution function.It could distinguish most of isomers that include cis-or trans-structure from organic compounds.Contributions for hydrocarbons and hydrocarbon derivatives containing oxygen,nitrogen,chlorine,bromine and sulfur,are given.Compared with the predictions,results made use of the most common existing group contribution methods,the overall average absolute difference of boiling point predictions of 417 organic compounds is 4.2 K;and the average absolute percent derivation is 1.0%,which is compared with 12.3 K and 3.2% with the method of Joback,12.1 K and 3.1% with the method of Constantinou-Gani.This new position contribution groups method is not only much more accurate but also has the advantages of simplicity and stability.展开更多
In this paper, a linear relationship between the logarithm of capacity factor k and normal boiling point to of the homologues has been derived, based on the basic retention equation of liquid chromatography according ...In this paper, a linear relationship between the logarithm of capacity factor k and normal boiling point to of the homologues has been derived, based on the basic retention equation of liquid chromatography according to statistical thermodyoamics proposed by professor Ln Peizhang and others, This equation has been verified by a large number of experimental data, all the strsight lines of lnk- of bumologues for different mobile phass coaiposltion cross each other at the same point, So the intereection point equation van proposed, wbich was used to prodict the retention valu, the result was satisfactory.展开更多
A molecular vector-type descriptor containing 6 variables is used to describe the structure of aromatic hydrocarbons (AHs) and relate to normal boiling points (bp) of AHs. The col relation coefficient (R) between the ...A molecular vector-type descriptor containing 6 variables is used to describe the structure of aromatic hydrocarbons (AHs) and relate to normal boiling points (bp) of AHs. The col relation coefficient (R) between the estimated bp and experimental bp is 0.9988 and the root mean square error (RMS) is 7.907 degreesC for 66 AHs. The RMS obtained by cross-validation is 9.131 degreesC, which implies the relationship model having good prediction ability.展开更多
Giant Steerable Science Mirror( GSSM) is the tertiary mirror of the Thirty Meter Telescope( TMT).To evaluate the performance of the GSSM under the mechanical vibration,the Normalized Point Source Sensitivity( PSSn) is...Giant Steerable Science Mirror( GSSM) is the tertiary mirror of the Thirty Meter Telescope( TMT).To evaluate the performance of the GSSM under the mechanical vibration,the Normalized Point Source Sensitivity( PSSn) is used to understand and characterize the optical performance degradation. First and foremost,the definition of the PSSn is shown and the calculation procedure of the PSSn at the work condition where the telescope aberration is much smaller than seeing is presented to reveal the relationship between PSSn and seeing.Then,the optical degradation due to vibration is achieved by the two methods: one is the statistics moment for the arbitrary froms of vibration and other one is spectrum method for wind load. After the theoretical presence,the simulation is processed. The multi-axis-accelerometers are used to achieve the motion of the mirror. After integrated to displacement signal,the measured signal is applied to the mathematical model of the GSSM and the optical performance degradation under certain mechanical vibration can be achieved. The PSSN flows from 0.996 to 0.994 under some dynamic vibration. And then,the wind load is applied to the mathematical model using spectrum method with the PSSN flows from 0.996 to 0.991. This paper can help the system engineers to predict the performance of the GSSM in various work condition. What is more,PSSn is able to be combined just by simple multiplication,so the optical performance degradation can be easily co-considered with other error sources.展开更多
In this paper, we study the normality criteria of meromorphic functions concerning shared fixed-points, we obtain: Let F be a family of meromorphic functions defined in a domain D. Let n, k ≥ 2 be two positive intege...In this paper, we study the normality criteria of meromorphic functions concerning shared fixed-points, we obtain: Let F be a family of meromorphic functions defined in a domain D. Let n, k ≥ 2 be two positive integers. For every f ∈ F, all of whose zeros have multiplicity at least (nk+2)/(n-1). If f(f(k))nand g(g(k))nshare z in D for each pair of functions f and g, then F is normal.展开更多
Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and a...Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and agricultural non-point source pollution control in the Dianchi Lake basin were studied,and countermeasures and suggestions of comprehensive control of agricultural non-point source pollution in the basin were proposed.展开更多
We present new connections among linear anomalous diffusion (AD), normal diffusion (ND) and the Central Limit Theorem (CLT). This is done by defining a point transformation to a new position variable, which we postula...We present new connections among linear anomalous diffusion (AD), normal diffusion (ND) and the Central Limit Theorem (CLT). This is done by defining a point transformation to a new position variable, which we postulate to be Cartesian, motivated by considerations from super-symmetric quantum mechanics. Canonically quantizing in the new position and momentum variables according to Dirac gives rise to generalized negative semi-definite and self-adjoint Laplacian operators. These lead to new generalized Fourier transformations and associated probability distributions, which are form invariant under the corresponding transform. The new Laplacians also lead us to generalized diffusion equations, which imply a connection to the CLT. We show that the derived diffusion equations capture all of the Fractal and Non-Fractal Anomalous Diffusion equations of O’Shaughnessy and Procaccia. However, we also obtain new equations that cannot (so far as we can tell) be expressed as examples of the O’Shaughnessy and Procaccia equations. The results show, in part, that experimentally measuring the diffusion scaling law can determine the point transformation (for monomial point transformations). We also show that AD in the original, physical position is actually ND when viewed in terms of displacements in an appropriately transformed position variable. We illustrate the ideas both analytically and with a detailed computational example for a non-trivial choice of point transformation. Finally, we summarize our results.展开更多
This paper presents a curve reconstruction algorithm based on discrete data points and normal vectors using B-splines.The proposed algorithm has been improved in three steps:parameterization of the discrete data point...This paper presents a curve reconstruction algorithm based on discrete data points and normal vectors using B-splines.The proposed algorithm has been improved in three steps:parameterization of the discrete data points with tangent vectors,the B-spline knot vector determination by the selected dominant points based on normal vectors,and the determination of the weight to balancing the two errors of the data points and normal vectors in fitting model.Therefore,we transform the B-spline fitting problem into three sub-problems,and can obtain the B-spline curve adaptively.Compared with the usual fitting method which is based on dominant points selected only by data points,the B-spline curves reconstructed by our approach can retain better geometric shape of the original curves when the given data set contains high strength noises.展开更多
由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段...由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段定位的方法。首先,针对SNOP的典型控制策略,分析FDN的短路故障特征。其次,计算配电网中不同故障位置电流正序分量的Tanimoto系数,通过对比不同位置的电流正序分量波形相似性,构建FDN短路故障定位判据,并通过Teager能量算子(Teager energy operation,TEO)实现故障时刻的精确定位,利用智能配电终端(smart terminal unit,STU)传递信息。最后,通过建模仿真对所提方法进行分析验证,结果表明该方法能够对故障区段进行准确定位,不受故障位置、故障类型、过渡电阻、采样频率及通信延时等因素的影响,验证了该方法的可行性与有效性。展开更多
为解决孤岛模式下交直流混合微电网稳定运行的问题,文中提出一种孤岛交直流混合微电网柔性多状态开关(soft normally open point, SNOP)统一下垂控制策略。该策略基于系统功率平衡关系,通过归一化方法将2条馈线的频率下垂特性和直流电...为解决孤岛模式下交直流混合微电网稳定运行的问题,文中提出一种孤岛交直流混合微电网柔性多状态开关(soft normally open point, SNOP)统一下垂控制策略。该策略基于系统功率平衡关系,通过归一化方法将2条馈线的频率下垂特性和直流电压下垂特性相结合,根据交流频率和直流电压的变化情况,判断系统的运行状态,并通过SNOP统一调节交流子网频率和直流子网电压,使交、直流微电网能够均衡承担系统总功率变化量,从而确保交流频率和直流电压稳定在系统允许范围内。同时,为了优先确保分布式电源的就近消纳,避免SNOP的非必要动作,设计了SNOP的调节死区,使得交、直流微电网能够优先利用各子网内分布式电源,从而减少SNOP交、直流侧功率的频繁交互。最后,通过MATLAB/Simulink仿真验证了所提统一下垂控制策略的有效性。展开更多
智能软开关(soft normally open point, SNOP)凭借其灵活的功率调节能力逐渐应用于配电网中。但由于大量分布式电源(distributed generation, DG)接入,SNOP受到线路容量的限制,调节能力有限。为发挥其最大调节能力,文中提出适用于配电...智能软开关(soft normally open point, SNOP)凭借其灵活的功率调节能力逐渐应用于配电网中。但由于大量分布式电源(distributed generation, DG)接入,SNOP受到线路容量的限制,调节能力有限。为发挥其最大调节能力,文中提出适用于配电系统的SNOP对线路有功功率裕度调节灵敏度的定义,将其作为SNOP调节能力的评价指标,由此建立SNOP的选址优化模型。在此基础上,引入系统节点电压裕度以及线路功率裕度2个安全评价指标,构建以综合运行裕度最大为目标函数的配电网运行优化模型。将上述模型转化为二阶锥模型,通过MATLAB工具实现该问题的有效求解。最后,通过改进的IEEE 33节点算例对所提模型与求解方法进行验证,进一步表明了所提选址方法能够发挥SNOP的最大调节作用,优化控制策略可以实现配电网安全经济运行。展开更多
In this paper, we present a robust subneighborhoods selection technique for feature detection on point clouds scattered over a piecewise smooth surface. The proposed method first identifies all potential features usin...In this paper, we present a robust subneighborhoods selection technique for feature detection on point clouds scattered over a piecewise smooth surface. The proposed method first identifies all potential features using covariance analysis of the local- neighborhoods. To further extract the accurate features from potential features, Gabriel triangles are created in local neighborhoods of each potential feature vertex. These triangles tightly attach to underlying surface and effectively reflect the local geometry struc- ture. Applying a shared nearest neighbor clustering algorithm on ~ 1 reconstructed normals of created triangle set, we classify the lo- cal neighborhoods of the potential feature vertex into multiple subneighborhoods. Each subneighborhood indicates a piecewise smooth surface. The final feature vertex is identified by checking whether it is locating on the intersection of the multiple surfaces. An advantage of this framework is that it is not only robust to noise, but also insensitive to the size of selected neighborhoods. Ex- perimental results on a variety of models are used to illustrate the effectiveness and robustness of our method.展开更多
Purpose: This study was performed to assess the utility and safety of an In-Office INR Monitoring Device and present a safe and efficient protocol for the management of patients on oral anticoagulants and/or antithrom...Purpose: This study was performed to assess the utility and safety of an In-Office INR Monitoring Device and present a safe and efficient protocol for the management of patients on oral anticoagulants and/or antithrombolytics requiring routine office oral and maxillofacial surgery. Patients and Methods: Sixty-one patients requiring “minor” oral and maxillofacial surgery being treated chronically with oral anticoagulation (warfarin) were entered into the study and compared in 2 groups. The control group (n = 29) was managed by discontinuing warfarin and any anti-platelet medication(s) prior to surgery. In the study group (n = 30), the decision to continue or withhold warfarin was determined by a protocol in which patients are 1) stratified based on risk for thromboembolism, and 2) classified as requiring “major” or “minor” surgery. Procedures categorized as “minor” surgery included dental extraction(s), dental implants, soft tissue and bone biopsies, and preprosthetic bone surgery, and incision and drainage. Warfarin and antiplatelet medication were not withheld in these patients, and a Point-of-Care In-Office INR Monitoring Device was used to obtain INR levels on the day of consultation and surgery. Local measures including removal of granulation tissue, packing, suturing, etc. were utilized for hemostasis. Results: The 30 patients in the study group maintained on warfarin readily achieved hemostasis using intraoperative local measures. The mean INR measured by the In-Office INR Monitoring Device was 2.36 with a range from 1.3 to 3.2. Study group patients underwent a total of 131 separate procedures including 108 dental extractions (impactions), placement of dental implants, preprosthetic bony surgery, bone cyst removal, soft tissue biopsies, facial skin cancer repair, and incision and drainage. One patient (3%) required “minor” intervention with removal of a “liver clot” on postop day 2 with repacking and suturing. The 29 patients in the control group discontinued off of war farin underwent a total of 99 procedures. One patient (3%) also required a “minor” intervention (repacking of extraction site). There were no “major” complications in either group. Conclusions: This study supports previous studies that minor oral surgery procedures can be safely performed while maintaining patients on warfarin minimizing the risk of a potentially devastating thromboembolic event. When deciding whether or not to withhold warfarin, this study supports the use of the proposed protocol based on 1) risk stratification for thromboembolism, 2) the need for “minor” versus “major” surgery, 3) and utilization of an In-Office INR Monitoring Device. An In-Office Point-of-Care INR measuring device can be a very effective tool to safely simplify and make the perioperative management of the anticoagulated patient more efficient for the patient and oral and maxillo facial surgeon.展开更多
点云配准是基于机器视觉进行工业复杂零件三维非接触精密测量的关键环节。为了提高点云配准的效率和准确性,提出一种基于改进法线计算的快速点特征直方图(Fast Point Feature Histograms, FPFH)特征描述子的点云配准方法。采用重心最近...点云配准是基于机器视觉进行工业复杂零件三维非接触精密测量的关键环节。为了提高点云配准的效率和准确性,提出一种基于改进法线计算的快速点特征直方图(Fast Point Feature Histograms, FPFH)特征描述子的点云配准方法。采用重心最近邻体素滤波器对点云进行预处理,减少点的数量同时保留表面细微特征。为解决传统迭代最近点(Iterative Closest Point, ICP)算法对初始位置敏感且收敛速度慢的问题,采用基于改进特征描述子的采样一致性(Sample Consensus Initial Alignment, SAC-IA)初始配准算法进行粗配准,使用基于KDtree加速的ICP算法进行精配准。本文选用三组点云数据,用不同的点云配准方法进行了测试。实验结果显示,在点云添加2%与5%噪声的情况下处理不同规模的点云数据时,所提出的方法配准所用时间和均方根误差(Root Mean Square Error, RMSE,ERMS)仍优于其它两种对比方法。展开更多
文摘A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distribution function.It could distinguish most of isomers that include cis-or trans-structure from organic compounds.Contributions for hydrocarbons and hydrocarbon derivatives containing oxygen,nitrogen,chlorine,bromine and sulfur,are given.Compared with the predictions,results made use of the most common existing group contribution methods,the overall average absolute difference of boiling point predictions of 417 organic compounds is 4.2 K;and the average absolute percent derivation is 1.0%,which is compared with 12.3 K and 3.2% with the method of Joback,12.1 K and 3.1% with the method of Constantinou-Gani.This new position contribution groups method is not only much more accurate but also has the advantages of simplicity and stability.
文摘In this paper, a linear relationship between the logarithm of capacity factor k and normal boiling point to of the homologues has been derived, based on the basic retention equation of liquid chromatography according to statistical thermodyoamics proposed by professor Ln Peizhang and others, This equation has been verified by a large number of experimental data, all the strsight lines of lnk- of bumologues for different mobile phass coaiposltion cross each other at the same point, So the intereection point equation van proposed, wbich was used to prodict the retention valu, the result was satisfactory.
文摘A molecular vector-type descriptor containing 6 variables is used to describe the structure of aromatic hydrocarbons (AHs) and relate to normal boiling points (bp) of AHs. The col relation coefficient (R) between the estimated bp and experimental bp is 0.9988 and the root mean square error (RMS) is 7.907 degreesC for 66 AHs. The RMS obtained by cross-validation is 9.131 degreesC, which implies the relationship model having good prediction ability.
基金Sponsored by the National Natural Science Foundation of China(Grant No.11403022)
文摘Giant Steerable Science Mirror( GSSM) is the tertiary mirror of the Thirty Meter Telescope( TMT).To evaluate the performance of the GSSM under the mechanical vibration,the Normalized Point Source Sensitivity( PSSn) is used to understand and characterize the optical performance degradation. First and foremost,the definition of the PSSn is shown and the calculation procedure of the PSSn at the work condition where the telescope aberration is much smaller than seeing is presented to reveal the relationship between PSSn and seeing.Then,the optical degradation due to vibration is achieved by the two methods: one is the statistics moment for the arbitrary froms of vibration and other one is spectrum method for wind load. After the theoretical presence,the simulation is processed. The multi-axis-accelerometers are used to achieve the motion of the mirror. After integrated to displacement signal,the measured signal is applied to the mathematical model of the GSSM and the optical performance degradation under certain mechanical vibration can be achieved. The PSSN flows from 0.996 to 0.994 under some dynamic vibration. And then,the wind load is applied to the mathematical model using spectrum method with the PSSN flows from 0.996 to 0.991. This paper can help the system engineers to predict the performance of the GSSM in various work condition. What is more,PSSn is able to be combined just by simple multiplication,so the optical performance degradation can be easily co-considered with other error sources.
文摘In this paper, we study the normality criteria of meromorphic functions concerning shared fixed-points, we obtain: Let F be a family of meromorphic functions defined in a domain D. Let n, k ≥ 2 be two positive integers. For every f ∈ F, all of whose zeros have multiplicity at least (nk+2)/(n-1). If f(f(k))nand g(g(k))nshare z in D for each pair of functions f and g, then F is normal.
基金Supported by Research on the Comprehensive Control Measures of Agricultural Non-point Source Pollution in the Dianchi Lake Basin Funded by Kunming Agricultural Bureau(2016JC01)Project of Yunnan Engineering Research Center for Urban Characteristic Agriculture(TSNY0201)+7 种基金Scientific Research Foundation of Yunnan Department of Education(2014Y390)Application Base Research Project for Young Scholars of Yunnan Province(2013FD040)Talent Introduction Project of Kunming University(YJL14005)Talent Introduction Foundation of Kunming University(YJL12010)Key Foundation of Kunming University(XJL12020)Scientific Research Project for Undergraduates of Kunming University(XJD16081)Research on the Ecology and Rational Distribution of Main Cultivars in Producing Areas of Raw Materials of China Tobacco in Yunnan ProvinceProject of Construction of the Dominant Key Subject(Ecology)in Universities and Colleges in Yunnan Province(05000511311)
文摘Based on Kunming statistical yearbook and field survey data of agricultural non-point source pollution in counties or districts in the Dianchi Lake basin,previous and current situation of agricultural production and agricultural non-point source pollution control in the Dianchi Lake basin were studied,and countermeasures and suggestions of comprehensive control of agricultural non-point source pollution in the basin were proposed.
文摘We present new connections among linear anomalous diffusion (AD), normal diffusion (ND) and the Central Limit Theorem (CLT). This is done by defining a point transformation to a new position variable, which we postulate to be Cartesian, motivated by considerations from super-symmetric quantum mechanics. Canonically quantizing in the new position and momentum variables according to Dirac gives rise to generalized negative semi-definite and self-adjoint Laplacian operators. These lead to new generalized Fourier transformations and associated probability distributions, which are form invariant under the corresponding transform. The new Laplacians also lead us to generalized diffusion equations, which imply a connection to the CLT. We show that the derived diffusion equations capture all of the Fractal and Non-Fractal Anomalous Diffusion equations of O’Shaughnessy and Procaccia. However, we also obtain new equations that cannot (so far as we can tell) be expressed as examples of the O’Shaughnessy and Procaccia equations. The results show, in part, that experimentally measuring the diffusion scaling law can determine the point transformation (for monomial point transformations). We also show that AD in the original, physical position is actually ND when viewed in terms of displacements in an appropriately transformed position variable. We illustrate the ideas both analytically and with a detailed computational example for a non-trivial choice of point transformation. Finally, we summarize our results.
基金Supported by the National Natural Science Foundation of China(Nos.1187113711572081)the Program for Liaoning Innovation Talents in University(No.LCR2018001)
文摘This paper presents a curve reconstruction algorithm based on discrete data points and normal vectors using B-splines.The proposed algorithm has been improved in three steps:parameterization of the discrete data points with tangent vectors,the B-spline knot vector determination by the selected dominant points based on normal vectors,and the determination of the weight to balancing the two errors of the data points and normal vectors in fitting model.Therefore,we transform the B-spline fitting problem into three sub-problems,and can obtain the B-spline curve adaptively.Compared with the usual fitting method which is based on dominant points selected only by data points,the B-spline curves reconstructed by our approach can retain better geometric shape of the original curves when the given data set contains high strength noises.
文摘由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段定位的方法。首先,针对SNOP的典型控制策略,分析FDN的短路故障特征。其次,计算配电网中不同故障位置电流正序分量的Tanimoto系数,通过对比不同位置的电流正序分量波形相似性,构建FDN短路故障定位判据,并通过Teager能量算子(Teager energy operation,TEO)实现故障时刻的精确定位,利用智能配电终端(smart terminal unit,STU)传递信息。最后,通过建模仿真对所提方法进行分析验证,结果表明该方法能够对故障区段进行准确定位,不受故障位置、故障类型、过渡电阻、采样频率及通信延时等因素的影响,验证了该方法的可行性与有效性。
文摘为解决孤岛模式下交直流混合微电网稳定运行的问题,文中提出一种孤岛交直流混合微电网柔性多状态开关(soft normally open point, SNOP)统一下垂控制策略。该策略基于系统功率平衡关系,通过归一化方法将2条馈线的频率下垂特性和直流电压下垂特性相结合,根据交流频率和直流电压的变化情况,判断系统的运行状态,并通过SNOP统一调节交流子网频率和直流子网电压,使交、直流微电网能够均衡承担系统总功率变化量,从而确保交流频率和直流电压稳定在系统允许范围内。同时,为了优先确保分布式电源的就近消纳,避免SNOP的非必要动作,设计了SNOP的调节死区,使得交、直流微电网能够优先利用各子网内分布式电源,从而减少SNOP交、直流侧功率的频繁交互。最后,通过MATLAB/Simulink仿真验证了所提统一下垂控制策略的有效性。
文摘智能软开关(soft normally open point, SNOP)凭借其灵活的功率调节能力逐渐应用于配电网中。但由于大量分布式电源(distributed generation, DG)接入,SNOP受到线路容量的限制,调节能力有限。为发挥其最大调节能力,文中提出适用于配电系统的SNOP对线路有功功率裕度调节灵敏度的定义,将其作为SNOP调节能力的评价指标,由此建立SNOP的选址优化模型。在此基础上,引入系统节点电压裕度以及线路功率裕度2个安全评价指标,构建以综合运行裕度最大为目标函数的配电网运行优化模型。将上述模型转化为二阶锥模型,通过MATLAB工具实现该问题的有效求解。最后,通过改进的IEEE 33节点算例对所提模型与求解方法进行验证,进一步表明了所提选址方法能够发挥SNOP的最大调节作用,优化控制策略可以实现配电网安全经济运行。
基金Supported by National Natural Science Foundation of China(No.u0935004,61173102)the Fundamental Research Funds for the Central Unibersities(DUT11SX08)
文摘In this paper, we present a robust subneighborhoods selection technique for feature detection on point clouds scattered over a piecewise smooth surface. The proposed method first identifies all potential features using covariance analysis of the local- neighborhoods. To further extract the accurate features from potential features, Gabriel triangles are created in local neighborhoods of each potential feature vertex. These triangles tightly attach to underlying surface and effectively reflect the local geometry struc- ture. Applying a shared nearest neighbor clustering algorithm on ~ 1 reconstructed normals of created triangle set, we classify the lo- cal neighborhoods of the potential feature vertex into multiple subneighborhoods. Each subneighborhood indicates a piecewise smooth surface. The final feature vertex is identified by checking whether it is locating on the intersection of the multiple surfaces. An advantage of this framework is that it is not only robust to noise, but also insensitive to the size of selected neighborhoods. Ex- perimental results on a variety of models are used to illustrate the effectiveness and robustness of our method.
文摘Purpose: This study was performed to assess the utility and safety of an In-Office INR Monitoring Device and present a safe and efficient protocol for the management of patients on oral anticoagulants and/or antithrombolytics requiring routine office oral and maxillofacial surgery. Patients and Methods: Sixty-one patients requiring “minor” oral and maxillofacial surgery being treated chronically with oral anticoagulation (warfarin) were entered into the study and compared in 2 groups. The control group (n = 29) was managed by discontinuing warfarin and any anti-platelet medication(s) prior to surgery. In the study group (n = 30), the decision to continue or withhold warfarin was determined by a protocol in which patients are 1) stratified based on risk for thromboembolism, and 2) classified as requiring “major” or “minor” surgery. Procedures categorized as “minor” surgery included dental extraction(s), dental implants, soft tissue and bone biopsies, and preprosthetic bone surgery, and incision and drainage. Warfarin and antiplatelet medication were not withheld in these patients, and a Point-of-Care In-Office INR Monitoring Device was used to obtain INR levels on the day of consultation and surgery. Local measures including removal of granulation tissue, packing, suturing, etc. were utilized for hemostasis. Results: The 30 patients in the study group maintained on warfarin readily achieved hemostasis using intraoperative local measures. The mean INR measured by the In-Office INR Monitoring Device was 2.36 with a range from 1.3 to 3.2. Study group patients underwent a total of 131 separate procedures including 108 dental extractions (impactions), placement of dental implants, preprosthetic bony surgery, bone cyst removal, soft tissue biopsies, facial skin cancer repair, and incision and drainage. One patient (3%) required “minor” intervention with removal of a “liver clot” on postop day 2 with repacking and suturing. The 29 patients in the control group discontinued off of war farin underwent a total of 99 procedures. One patient (3%) also required a “minor” intervention (repacking of extraction site). There were no “major” complications in either group. Conclusions: This study supports previous studies that minor oral surgery procedures can be safely performed while maintaining patients on warfarin minimizing the risk of a potentially devastating thromboembolic event. When deciding whether or not to withhold warfarin, this study supports the use of the proposed protocol based on 1) risk stratification for thromboembolism, 2) the need for “minor” versus “major” surgery, 3) and utilization of an In-Office INR Monitoring Device. An In-Office Point-of-Care INR measuring device can be a very effective tool to safely simplify and make the perioperative management of the anticoagulated patient more efficient for the patient and oral and maxillo facial surgeon.
