26 research outputs found
Minimum-acceleration local modification method for planning tool orientations in 5-axis ball-end machining
In 5-axis CNC machining, it is important to avoid drastic changes of tool orientations for improving kinematics performances of two rotary axes of 5-axis machine tools and achieving good machining surface quality. For this purpose, in this paper, a minimum-acceleration local modification (MALM) method is proposed to plan the tool orientations for 5-axis ball-end machining. First, with several specified representative tool orientations (RTOs), initial tool orientations are generated efficiently along the tool path by quaternion interpolation (QI) method while guaranteeing no machining interferences. Then, the generated tool orientations are checked whether the angular accelerations of the rotary axes exceed their drive limits, and the over-limit areas (OLAs), which are involved in tool orientation modification, are subsequently identified. In the OLAs, the minimum-acceleration model for local modification of tool orientations is given in machine coordinate system (MCS), and then is used to adjust the tool orientations to improve the kinematics performance of the rotary axes. Finally, the experiments demonstrated that this method can improve significantly the kinematics performances of the rotary axes
Homeodomain transcription factor CDX1 is required for the transcriptional induction of PPARγ in intestinal cell differentiation
Comprehensive Glycomic Analysis Reveals that Human Serum Albumin Glycation Specifically Affects the Pharmacokinetics and Efficacy of Different Anticoagulant Drugs in Diabetes.
Long-term hyperglycemia in diabetic patients leads to human serum albumin (HSA) glycation, which may impair HSA function as a transport protein and affect the therapeutic efficacy of anticoagulants in diabetic patients. In this study, a novel mass spectrometry (MS) approach was developed to reveal the differences in the profiles of HSA glycation sites between diabetic and healthy subjects. K199 was the glycation site most significantly changed in diabetic patients, contributing to different interactions of glycated HSA (gHSA) and normal HSA with two types of anticoagulant drugs, heparin and warfarin