Aim To study the effect of aerodynamically stabilized seeker dynamics on guided bomb system analysis. Methods A thorough analysis of aerodynamically stabilized seeker dynamics was made to show that because of the mu...Aim To study the effect of aerodynamically stabilized seeker dynamics on guided bomb system analysis. Methods A thorough analysis of aerodynamically stabilized seeker dynamics was made to show that because of the much smaller time constant, its dynamic model can be greatly simplified. Results and Conclusion In guided bomb guidance/control digital simulation, with the use of the simplified seeker model, simulation time can be reduced without the loss of simulation accuracy.展开更多
Objective To probe into the function mechanism of penetration therapy with head electrical acupuncture on Parkinson＇s disease. Methods Microinjection of 6-hydroxydopamin （6-OHDA） on the left cor- pus striatum was a...Objective To probe into the function mechanism of penetration therapy with head electrical acupuncture on Parkinson＇s disease. Methods Microinjection of 6-hydroxydopamin （6-OHDA） on the left cor- pus striatum was adopted to prepare rotation model of Parkinson^s disease in rat. Penetration therapy with head electrical acupuncture was administered in treatment. Normal group, sham-operation group, model group and penetration therapy group were set up. （1）lmmunohistochemical （IHC） method was used to test the morphology and count of positive cell of tyrosine hydroxylase （TH）. （2）RT-PCR technology was used to detect the expression of nestin mRNA of neural stem cell （NSC）. Results （1）Compared with model group, in pene- tration therapy group, the expressions of TH-positive neurons in immune response were increased in areal density （AD）, numerical density （ND） and integrating optic density （P〈0.05）. （2）Compared with model group, in penetration therapy group, the expression of nestin mRNA was increased （P〈0. 05）. Conclusion Penetration therapy with head electrical acupuncture promotes the proliferation of endogenous neural stem cells in substantia nigra of rat model of Parkinson＇s disease.展开更多
To solve the mismatch between the candidate model and the reference model caused by the time change of the tracked head, a novel mean shift algorithm based on a fusion model is provided. A fusion model is employed to ...To solve the mismatch between the candidate model and the reference model caused by the time change of the tracked head, a novel mean shift algorithm based on a fusion model is provided. A fusion model is employed to describe the tracked head by sampling the models of the fore-head and the back-head under different situations. Thus the fusion head reference model is represented by the color distribution estimated from both the fore- head and the back-head. The proposed tracking system is efficient and it is easy to realize the goal of continual tracking of the head by using the fusion model. The results show that the new tracker is robust up to a 360°rotation of the head on a cluttered background and the tracking precision is improved.展开更多
Nose deflection control is a new concept of fast response control model.The partial nose of projectile deflects a certain angle relative to the axis of projectile body and then pressure difference emerges on the windw...Nose deflection control is a new concept of fast response control model.The partial nose of projectile deflects a certain angle relative to the axis of projectile body and then pressure difference emerges on the windward and leeward sides of warhead.Consequently,aerodynamic control force is generated.This control way has high control efficiency and very good application prospects in the ammunition system.Nose deflection actuator based on smart material and structure enables projectile body morphing to obtain additional aerodynamic force and moment,changes the aerodynamic characteristics in the projectile flight process,produces the corresponding balance angle and sideslip angle resulting in motor overload,adjusts flight moving posture to control the ballistics,finally changes shooting range and improves firing accuracy.In order to study characteristics of self-adaptive control projectile,numerical simulations are conducted by using fluid dynamics software ANSYS FLUENT for stabilized rocket projectile.The aerodynamic characteristics at different nose delectation angles,different Mach numbers and different angles of attack are obtained and compared.The results show that the nose deflection control has great influence on the head of rocket projectile,and it causes the asymmetry of the flow field structure and the increase of pressure differences of the warhead on the windward and leeward surface,which results in a larger lift.Finally,ballistics experiments are done for verification.The results can offer theoretical basis for self-adaptive rocket projectile design and optimization and also provide new ideas and methods for field smart ammunition research.展开更多
The worldwide research status of head tracking is introduced and the works made in the research of the predictive algorithm and in the exploration of the rule of the head tracking are set forth. A time delay model f...The worldwide research status of head tracking is introduced and the works made in the research of the predictive algorithm and in the exploration of the rule of the head tracking are set forth. A time delay model for the telerobotic scout system is built. In respect of eliminating error caused by time delay and making reasonable prediction to the data stream, many methods are experimented in order to realize the aim of real time tracking. The application of extrapolation algorithm and auto recursive algorithm in the orientation tracking is described in detail. These two algorithms are realized in Matlab environment. Through analysis of the curves generated by using these two predictive algorithms, an appropriate method was applied in the telerobotic scout system. The effect is satisfying.展开更多
Head and neck cancers(HNCs) are aggressive tumors that typically demonstrate a high glycolytic rate, which results in resistance to cytotoxic therapy and poor prognosis. Due to their location these tumors specifically...Head and neck cancers(HNCs) are aggressive tumors that typically demonstrate a high glycolytic rate, which results in resistance to cytotoxic therapy and poor prognosis. Due to their location these tumors specifically impair food intake and quality of life, so that prevention of weight loss through nutrition support becomes an important treatment goal. Dietary restriction of carbohydrates(CHOs) and their replacement with fat, mostly in form of a ketogenic diet(KD), have been suggested to accommodate for both the altered tumor cell metabolism and cancer-associated weight loss. In this review, I present three specific rationales for CHO restriction and nutritional ketosis as supportive treatment options for the HNC patient. These are(1) targeting the origin and specific aspects of tumor glycolysis;(2) protecting normal tissue from but sensitizing tumor tissue to radiation- and chemotherapy induced cell kill;(3) supporting body and muscle mass maintenance. While most of these benefits of CHO restriction apply to cancer in general, specific aspects of implementation are discussed in relation to HNC patients. While CHO restriction seems feasible in HNC patients the available evidence indicates that its role may extend beyond fighting malnutrition to fighting HNC itself.展开更多
AIM: To investigate the effectiveness of head compensatory postures to ensure safe oropharyngeal transit. METHODS: A total of 321 dysphagia patients were enrolled and assessed with videofluoromanometry (VFM). The dysp...AIM: To investigate the effectiveness of head compensatory postures to ensure safe oropharyngeal transit. METHODS: A total of 321 dysphagia patients were enrolled and assessed with videofluoromanometry (VFM). The dysphagia patients were classified as follows: safe transit; penetration without aspiration; aspiration before, during or after swallowing; multiple aspirations and no transit. The patients with aspiration or no transit were tested with VFM to determine whether compensatory postures could correct their swallowing disorder. RESULTS: VFM revealed penetration without aspiration in 71 patients (22.1%); aspiration before swallowing in 17 patients (5.3%); aspiration during swallowing in 32 patients (10%); aspiration after swallowing in 21 patients (6.5%); multiple aspirations in six patients (1.9%); no transit in five patients (1.6%); and safe transit in 169 patients (52.6%). Compensatory postures guaranteed a safe transit in 66/75 (88%) patients with aspiration or no transit. A chin-down posture achieved a safe swallow in 42/75 (56%) patients, a head-turned posture in 19/75 (25.3%) and a hyperextended head posture in 5/75 (6.7%). The compensatory postures were not effective in 9/75 (12%) cases. CONCLUSION: VFM allows the speech-language therapist to choose the most effective compensatory posture without a trial-and-error process and check the effectiveness of the posture.展开更多
AIM:To determine the rate of use and non-use of prophylactic percutaneous endoscopic gastrostomy(PEG) tubes among patients with head and neck cancer(HNC) patients.METHODS:All patients with HNC undergoing PEG between J...AIM:To determine the rate of use and non-use of prophylactic percutaneous endoscopic gastrostomy(PEG) tubes among patients with head and neck cancer(HNC) patients.METHODS:All patients with HNC undergoing PEG between January 01,2004 and June 30,2006 were identified.Patients(or their next-of-kin) were surveyed by phone and all available medical records and cancer registry data were reviewed.Prophylactic PEG was def ined as placement in the absence of dysphagia and prior to radiation or chemoradiation.Each patient with a prophylactic PEG was assessed for cancer diagnosis,type of therapy,PEG use,and complications related to PEG.RESULTS:One hundred and three patients had PEG tubes placed for HNC.Thirty four patients(33%) could not be contacted for follow-up.Of the 23(22.3%) patients with prophylactic PEG tubes,11/23(47.8%) either never used the PEG or used it for less than 2 wk.No association with PEG use vs non-use was observed for cancer diagnosis,stage,or specific cancer treatment.Non-use or limited use was observed in 3/6(50%) treated with radiation alone vs 8/17(47.1%) treated with chemoradiation(P = 1.0),and 3 of 10(30%) treated with surgery vs 8 of 13(62%) not treated with surgery(P = 0.21).Minor complications were reported in 5/23(21.7%).One(4.3%) major complication was reported.CONCLUSION:There is a high rate of unnecessary PEG placement when done prophylactically in patients with head and neck cancer.展开更多
文摘Aim To study the effect of aerodynamically stabilized seeker dynamics on guided bomb system analysis. Methods A thorough analysis of aerodynamically stabilized seeker dynamics was made to show that because of the much smaller time constant, its dynamic model can be greatly simplified. Results and Conclusion In guided bomb guidance/control digital simulation, with the use of the simplified seeker model, simulation time can be reduced without the loss of simulation accuracy.
基金the Excellent Discipline Leadership Fund Project of Harbin Science-Technology Administration :2006RFXYS044
文摘Objective To probe into the function mechanism of penetration therapy with head electrical acupuncture on Parkinson＇s disease. Methods Microinjection of 6-hydroxydopamin （6-OHDA） on the left cor- pus striatum was adopted to prepare rotation model of Parkinson^s disease in rat. Penetration therapy with head electrical acupuncture was administered in treatment. Normal group, sham-operation group, model group and penetration therapy group were set up. （1）lmmunohistochemical （IHC） method was used to test the morphology and count of positive cell of tyrosine hydroxylase （TH）. （2）RT-PCR technology was used to detect the expression of nestin mRNA of neural stem cell （NSC）. Results （1）Compared with model group, in pene- tration therapy group, the expressions of TH-positive neurons in immune response were increased in areal density （AD）, numerical density （ND） and integrating optic density （P〈0.05）. （2）Compared with model group, in penetration therapy group, the expression of nestin mRNA was increased （P〈0. 05）. Conclusion Penetration therapy with head electrical acupuncture promotes the proliferation of endogenous neural stem cells in substantia nigra of rat model of Parkinson＇s disease.
基金The National Natural Science Foundation of China(No.60672094,60673188,U0735004)the National High Technology Research and Development Program of China(863 Program)(No.2008AA01Z303)the National Basic Research Program of China (973 Program)(No.2009CB320804)
文摘To solve the mismatch between the candidate model and the reference model caused by the time change of the tracked head, a novel mean shift algorithm based on a fusion model is provided. A fusion model is employed to describe the tracked head by sampling the models of the fore-head and the back-head under different situations. Thus the fusion head reference model is represented by the color distribution estimated from both the fore- head and the back-head. The proposed tracking system is efficient and it is easy to realize the goal of continual tracking of the head by using the fusion model. The results show that the new tracker is robust up to a 360°rotation of the head on a cluttered background and the tracking precision is improved.
文摘Nose deflection control is a new concept of fast response control model.The partial nose of projectile deflects a certain angle relative to the axis of projectile body and then pressure difference emerges on the windward and leeward sides of warhead.Consequently,aerodynamic control force is generated.This control way has high control efficiency and very good application prospects in the ammunition system.Nose deflection actuator based on smart material and structure enables projectile body morphing to obtain additional aerodynamic force and moment,changes the aerodynamic characteristics in the projectile flight process,produces the corresponding balance angle and sideslip angle resulting in motor overload,adjusts flight moving posture to control the ballistics,finally changes shooting range and improves firing accuracy.In order to study characteristics of self-adaptive control projectile,numerical simulations are conducted by using fluid dynamics software ANSYS FLUENT for stabilized rocket projectile.The aerodynamic characteristics at different nose delectation angles,different Mach numbers and different angles of attack are obtained and compared.The results show that the nose deflection control has great influence on the head of rocket projectile,and it causes the asymmetry of the flow field structure and the increase of pressure differences of the warhead on the windward and leeward surface,which results in a larger lift.Finally,ballistics experiments are done for verification.The results can offer theoretical basis for self-adaptive rocket projectile design and optimization and also provide new ideas and methods for field smart ammunition research.
文摘The worldwide research status of head tracking is introduced and the works made in the research of the predictive algorithm and in the exploration of the rule of the head tracking are set forth. A time delay model for the telerobotic scout system is built. In respect of eliminating error caused by time delay and making reasonable prediction to the data stream, many methods are experimented in order to realize the aim of real time tracking. The application of extrapolation algorithm and auto recursive algorithm in the orientation tracking is described in detail. These two algorithms are realized in Matlab environment. Through analysis of the curves generated by using these two predictive algorithms, an appropriate method was applied in the telerobotic scout system. The effect is satisfying.
文摘Head and neck cancers(HNCs) are aggressive tumors that typically demonstrate a high glycolytic rate, which results in resistance to cytotoxic therapy and poor prognosis. Due to their location these tumors specifically impair food intake and quality of life, so that prevention of weight loss through nutrition support becomes an important treatment goal. Dietary restriction of carbohydrates(CHOs) and their replacement with fat, mostly in form of a ketogenic diet(KD), have been suggested to accommodate for both the altered tumor cell metabolism and cancer-associated weight loss. In this review, I present three specific rationales for CHO restriction and nutritional ketosis as supportive treatment options for the HNC patient. These are(1) targeting the origin and specific aspects of tumor glycolysis;(2) protecting normal tissue from but sensitizing tumor tissue to radiation- and chemotherapy induced cell kill;(3) supporting body and muscle mass maintenance. While most of these benefits of CHO restriction apply to cancer in general, specific aspects of implementation are discussed in relation to HNC patients. While CHO restriction seems feasible in HNC patients the available evidence indicates that its role may extend beyond fighting malnutrition to fighting HNC itself.
文摘AIM: To investigate the effectiveness of head compensatory postures to ensure safe oropharyngeal transit. METHODS: A total of 321 dysphagia patients were enrolled and assessed with videofluoromanometry (VFM). The dysphagia patients were classified as follows: safe transit; penetration without aspiration; aspiration before, during or after swallowing; multiple aspirations and no transit. The patients with aspiration or no transit were tested with VFM to determine whether compensatory postures could correct their swallowing disorder. RESULTS: VFM revealed penetration without aspiration in 71 patients (22.1%); aspiration before swallowing in 17 patients (5.3%); aspiration during swallowing in 32 patients (10%); aspiration after swallowing in 21 patients (6.5%); multiple aspirations in six patients (1.9%); no transit in five patients (1.6%); and safe transit in 169 patients (52.6%). Compensatory postures guaranteed a safe transit in 66/75 (88%) patients with aspiration or no transit. A chin-down posture achieved a safe swallow in 42/75 (56%) patients, a head-turned posture in 19/75 (25.3%) and a hyperextended head posture in 5/75 (6.7%). The compensatory postures were not effective in 9/75 (12%) cases. CONCLUSION: VFM allows the speech-language therapist to choose the most effective compensatory posture without a trial-and-error process and check the effectiveness of the posture.
文摘AIM:To determine the rate of use and non-use of prophylactic percutaneous endoscopic gastrostomy(PEG) tubes among patients with head and neck cancer(HNC) patients.METHODS:All patients with HNC undergoing PEG between January 01,2004 and June 30,2006 were identified.Patients(or their next-of-kin) were surveyed by phone and all available medical records and cancer registry data were reviewed.Prophylactic PEG was def ined as placement in the absence of dysphagia and prior to radiation or chemoradiation.Each patient with a prophylactic PEG was assessed for cancer diagnosis,type of therapy,PEG use,and complications related to PEG.RESULTS:One hundred and three patients had PEG tubes placed for HNC.Thirty four patients(33%) could not be contacted for follow-up.Of the 23(22.3%) patients with prophylactic PEG tubes,11/23(47.8%) either never used the PEG or used it for less than 2 wk.No association with PEG use vs non-use was observed for cancer diagnosis,stage,or specific cancer treatment.Non-use or limited use was observed in 3/6(50%) treated with radiation alone vs 8/17(47.1%) treated with chemoradiation(P = 1.0),and 3 of 10(30%) treated with surgery vs 8 of 13(62%) not treated with surgery(P = 0.21).Minor complications were reported in 5/23(21.7%).One(4.3%) major complication was reported.CONCLUSION:There is a high rate of unnecessary PEG placement when done prophylactically in patients with head and neck cancer.
