The nonholonomic motion planning of a free-falling cat is investigated. Nonholonomicity arises in a free-falling cat subject to nonintegrable angle velocity constraints or nonintegrable conservation laws. When the tot...The nonholonomic motion planning of a free-falling cat is investigated. Nonholonomicity arises in a free-falling cat subject to nonintegrable angle velocity constraints or nonintegrable conservation laws. When the total angular momentum is zero, the motion equation of a free-falling cat is established based on the model of two symmetric rigid bodies and conservation of angular momentum. The control of system can be converted to the problem of nonholonomic motion planning for a free-falling cat. Based on Ritz approximation theory, the Gauss-Newton method for motion planning by a falling cat is proposed. The effectiveness of the numerical algorithm is demonstrated through simulation on model of a free-falling cat.展开更多
An optimal motion planning of a free-falling cat based on the spline approximation is investigated.Nonholonomicity arises in a free-falling cat subjected to nonintegrable velocity constraints or nonintegrable conserva...An optimal motion planning of a free-falling cat based on the spline approximation is investigated.Nonholonomicity arises in a free-falling cat subjected to nonintegrable velocity constraints or nonintegrable conservation laws.The equation of dynamics of a free-falling cat is obtained by using the model of two symmetric rigid bodies.The control of the system can be converted to the motion planning problem for a driftless system.A cost function is used to incorporate the final errors and control energy.The motion planning is to determine control inputs to minimize the cost function and is formulated as an infinite dimensional optimal control problem.By using the control parameterization,the infinite dimensional optimal control problem can be transformed to a finite dimensional one.The particle swarm optimization(PSO) algorithm with the cubic spline approximation is proposed to solve the finite dimension optimal control problem.The cubic spline approximation is introduced to realize the control parameterization.The resulting controls are smooth and the initial and terminal values of the control inputs are zeros,so they can be easily generated by experiment.Simulations are also performed for the nonholonomic motion planning of a free-falling cat.Simulated experimental results show that the proposed algorithm is more effective than the Newtoian algorithm.展开更多
BACKGROUND Cat scratch disease(CSD)is the most common human infection caused by Barto-nella henselae(B.henselae).The main manifestation is self-limited lymphaden-opathy that primarily affects adolescents,and typically...BACKGROUND Cat scratch disease(CSD)is the most common human infection caused by Barto-nella henselae(B.henselae).The main manifestation is self-limited lymphaden-opathy that primarily affects adolescents,and typically resolves without treat-ment within 2-4 months.However,individuals with compromised immune systems or immunodeficiency require specific antibacterial therapy following diagnosis.Due to its low incidence,nonspecific clinical manifestations,and diagnostic limitations,this condition often poses challenges for clinicians in terms of missed diagnoses and misdiagnoses.CASE SUMMARY The child was ultimately diagnosed with CSD.The primary manifestations included nocturnal fever,enlargement of lymph nodes in the neck,axilla and groin,and suspected brucellosis;however,both brucellosis tests conducted during the course of the illness yielded negative results.Bone marrow cytology indicated stimulated proliferation.Lymph node biopsy indicated hyperplasia of lymphoid tissue in the cervical lymph nodes(right),with combined immunohisto-chemical findings indicating reactive hyperplasia.Immunohistochemical analysis revealed CD20 B(+),CD3 T(+),BCL-6(+),and BCL-2(-).CD21 FDC networks were present and Ki67 expression in the germinal center was~80%.Blood next-generation sequencing indicated B.henselae sequence number was 3.Serological test results demonstrated positive antibody response to B.henselae IgG(+),B.henselae IgM(+),Bartonella quintana(B.quintana)IgG(-)and B.quintana IgM(-),and the final diagnosis was CSD.CONCLUSION In patients presenting with fever at night and swollen lymph nodes of unknown origin,CSD should be considered.展开更多
基金Project supported by the National Natural Science Foundation of China (No.10372014)the Natural Science Foundation of Beijing (No.1072008)
文摘The nonholonomic motion planning of a free-falling cat is investigated. Nonholonomicity arises in a free-falling cat subject to nonintegrable angle velocity constraints or nonintegrable conservation laws. When the total angular momentum is zero, the motion equation of a free-falling cat is established based on the model of two symmetric rigid bodies and conservation of angular momentum. The control of system can be converted to the problem of nonholonomic motion planning for a free-falling cat. Based on Ritz approximation theory, the Gauss-Newton method for motion planning by a falling cat is proposed. The effectiveness of the numerical algorithm is demonstrated through simulation on model of a free-falling cat.
基金supported by the National Natural Science Foundation of China (Grant No. 11072038)the Municipal Key Programs of Natural Science Foundation of Beijing,China (Grant No. KZ201110772039)
文摘An optimal motion planning of a free-falling cat based on the spline approximation is investigated.Nonholonomicity arises in a free-falling cat subjected to nonintegrable velocity constraints or nonintegrable conservation laws.The equation of dynamics of a free-falling cat is obtained by using the model of two symmetric rigid bodies.The control of the system can be converted to the motion planning problem for a driftless system.A cost function is used to incorporate the final errors and control energy.The motion planning is to determine control inputs to minimize the cost function and is formulated as an infinite dimensional optimal control problem.By using the control parameterization,the infinite dimensional optimal control problem can be transformed to a finite dimensional one.The particle swarm optimization(PSO) algorithm with the cubic spline approximation is proposed to solve the finite dimension optimal control problem.The cubic spline approximation is introduced to realize the control parameterization.The resulting controls are smooth and the initial and terminal values of the control inputs are zeros,so they can be easily generated by experiment.Simulations are also performed for the nonholonomic motion planning of a free-falling cat.Simulated experimental results show that the proposed algorithm is more effective than the Newtoian algorithm.
基金Supported by Shaanxi Natural Science Foundation,No.2020SF-004.
文摘BACKGROUND Cat scratch disease(CSD)is the most common human infection caused by Barto-nella henselae(B.henselae).The main manifestation is self-limited lymphaden-opathy that primarily affects adolescents,and typically resolves without treat-ment within 2-4 months.However,individuals with compromised immune systems or immunodeficiency require specific antibacterial therapy following diagnosis.Due to its low incidence,nonspecific clinical manifestations,and diagnostic limitations,this condition often poses challenges for clinicians in terms of missed diagnoses and misdiagnoses.CASE SUMMARY The child was ultimately diagnosed with CSD.The primary manifestations included nocturnal fever,enlargement of lymph nodes in the neck,axilla and groin,and suspected brucellosis;however,both brucellosis tests conducted during the course of the illness yielded negative results.Bone marrow cytology indicated stimulated proliferation.Lymph node biopsy indicated hyperplasia of lymphoid tissue in the cervical lymph nodes(right),with combined immunohisto-chemical findings indicating reactive hyperplasia.Immunohistochemical analysis revealed CD20 B(+),CD3 T(+),BCL-6(+),and BCL-2(-).CD21 FDC networks were present and Ki67 expression in the germinal center was~80%.Blood next-generation sequencing indicated B.henselae sequence number was 3.Serological test results demonstrated positive antibody response to B.henselae IgG(+),B.henselae IgM(+),Bartonella quintana(B.quintana)IgG(-)and B.quintana IgM(-),and the final diagnosis was CSD.CONCLUSION In patients presenting with fever at night and swollen lymph nodes of unknown origin,CSD should be considered.