Automatic tool path generation for numerically controlled machining of sculptured surfaces

This dissertation presents four new tool path generation approaches for numerically controlled machining of sculptured surfaces: TRI\sb-XYINDEX, FINISH, FIVEX\sb-INDEX, FIX\sb-AXIS\sb-INDEX. All of the above systems index the tool across the object surface in the Cartesian space so that evenly distributed tool paths are accomplished. TRI\sb-XYINDEX is a three-axis tool path generation system which uses a surface triangle set (STS) representation of the surface for tool position calculations. Surface edges are detected with local searching algorithms. Quick tool positioning is achieved by selecting candidate elements of polygons. Test results show that TRI\sb-XYINDEX is more efficient when machining surfaces which are relatively flat while the discrete point approach is faster for highly curved surfaces. FINISH was developed for generating three-axis ball-end tool paths for local surface finishing. It was based on the SPS. Given a surface with excess material represented by a set of discrete points, FINISH automatically identifies the undercut areas. Results show that FINISH provides significant improvements in machining efficiency. FIVEX\sb-INDEX is developed for generating five-axis flat-end tool paths. It uses an STS approximation. Contact points on the surface are derived from edge lists obtained from the intersections of vertical cutting planes with the polygon set. The distances between adjacent end points set an initial step-forward increment between surface contact points. To verify tool movements, some intermediate tool positions are interpolated. The key features of FIVEX\sb-INDEX are: (1) a polygon set representing an object which may be composed of multiple surfaces; (2) Surface contact point generation by cutting plane intersection; (3) simple tool incrementing and positioning algorithms; (4) minimal user interaction; (5) user controlled accuracy of resulting tool paths. FIX\sb-AXIS\sb-INDEX is a subsystem of FIVEX\sb-INDEX, generating tool paths for a tool with fixed orientations. Surface contact points are generated similar to FIVEX\sb-INDEX while tool positions are corrected with the highest point technique along the tool axis direction. Linear fitting is applied to output tool positions. FIX\sb-AXIS\sb-INDEX is preferred for machining surfaces curved in one direction, such as ruled surfaces. Test results show that FIX\sb-AXIS\sb-INDEX can serve as a three-axis tool path generation system but a five-axis machine is required to do it. (Abstract shortened by UMI.)

Creative design education research on multi-dimensional integration of visual communication design under the driving force of digital design

In 2022, a new era was born - “meta universe”, the concept of the rapid potential to penetrate into all walks of life, and with the arrival of the “meta universe” era, its transformation and change also bring new opportunities to the fi eld of visual communication design. In the more than 40 years of reform and opening up, visual communication design has undergone several periods of educational development from the change of discipline names: Decoration design, graphic design and visual communication design period, from the name change, it is not diffi cult to see that visual communication design is changing step by step towards the integration of all media, especially in the “new liberal arts”, “digital design”, “meta-universe” driven by this big change, visual communication design has further become a cross-border design integration professional

Developing competitive advantage for a restaurant

As public concerns about food safety and health increase, many people are raising their expectations of food quality and safety. To help a restaurant establish competitive advantages with food traceability control is the study purpose. The research problems include how the food traceability system can improve food quality and safety; how it will bring competitive advantages for the restaurant; and whether it is adaptable to the restaurant. The primary data was obtained by interviewing key participants in the restaurant’s food supply chain. The data is reliable as triangulation data shows similarities. The study finds that there is a willingness to build the food traceability system regardless of resources deficiency, as participants all agree that a food traceability system can help enhance food quality and safety. The innovation outcome shows a benefit that food traceability system can bring is adequate updated information along the food supply chain according to published food traceability case studies. Conclusions of the research are that a food traceability system can help improve food quality and safety. Furthermore, it also presents as a source of competitive advantage. A computerised traceability system can offer maximum information along the supply chain, which can help the organisation respond faster to changes, and make a strategic plan in supply, inventory and production with lower cost. Therefore, the research recommends that the restaurant introduce a suitable computerised food traceability system to obtain competitive advantages

A surrogate model construction strategy for bio-oil using ReaxFF molecular dynamics

Surrogate fuel model is useful as representative of simplified complex fuel mixture in description of their chemical kinetics in pyrolysis or oxidation conditions. This work propose a surrogate model construction strategy for bio-oil using ReaxFF molecular dynamics. A 24-component bio-oil model was constructed as a baseline model for real bio-oil based on the literature reported data of GC-MS analysis for bio-oil yielded from fast pyrolysis of Pterocarpus Indicus. According to the chemical constituent and functional groups in the 24-component bio-oil model, 5 surrogate bio-oil models each containing 6 components were formulated. ReaxFF MD simulations are performed on the 6-component surrogates and the 24-component oil model under the same oxidation conditions. In addition to element ratio comparison, the surrogate models are validated by comparing the simulated temporal evolution of major reactants and products including radicals using the 24-component model as a baseline. Please click Additional Files below to see the full abstract

HSP90 inhibitors stimulate DNAJB4 protein expression through a mechanism involving N6-methyladenosine.

Small-molecule inhibitors for the 90-kDa heat shock protein (HSP90) have been extensively exploited in preclinical studies for the therapeutic interventions of human diseases accompanied with proteotoxic stress. By using an unbiased quantitative proteomic method, we uncover that treatment with three HSP90 inhibitors results in elevated expression of a large number of heat shock proteins. We also demonstrate that the HSP90 inhibitor-mediated increase in expression of DNAJB4 protein occurs partly through an epitranscriptomic mechanism, and is substantially modulated by the writer, eraser, and reader proteins of N6-methyladenosine (m6A). Furthermore, exposure to ganetespib leads to elevated modification levels at m6A motif sites in the 5'-UTR of DNAJB4 mRNA, and the methylation at adenosine 114 site in the 5'-UTR promotes the translation of the reporter gene mRNA. This m6A-mediated mechanism is also at play upon heat shock treatment. Cumulatively, we unveil that HSP90 inhibitors stimulate the translation of DNAJB4 through an epitranscriptomic mechanism

From May You? To Do you Mind? A Case Study of ILP Development in Requests

This is a case study about interlanguage pragmatic (ILP) development in speech acts of request based on natural as well as elicited data from a 12-year-old chinese girl (Amy) over the period of her seven-month stay in tlawai'i. The two research questions are: (a) To what extent did Amy's performance in requests change over time with regard to request realization strategies and modification (b) How was Amy's request development identical with or different from the participants in previous studies? The analysis and results of the data show that in request strategres there is a shift from conventional indirectness to directness and nonconventional indirectness in accordance with the degree of request imposition and obligation/right of the interlocutors, but no variation is observed with respect to the social distance between the interlocutors. For request modification the politeness marker please is consistently the primary internal modification device, and there is a decrease in the use of grounders in external modification over the time. Amy's early reliance on speech formulas, the overwhelming use of conventional indirect strategies ard the politeness marker please, the improvernent in strategies prior to that in realizational linguistic means, the imitation learning strategy, and the function of conscious noticing are consistent with the findings in previous studies. However, the acquisitional sequence of requestive strategies the sensitivity of some situational factors, and the decrease in the use of grounders are aspects different from previous studies

Comparative Analysis of Clinical Epidemiology and Pathological Characteristics of 908 Patients with Primary Lung Cancer of Hunan Province in 1997 and 2007

Background and objective Epidemiology of lung cancer will be changed along with time and region. The aim of this study is to acknowledge the tendency of primary lung cancer in hunan province in recent years by comparing and analyzing the distribution of gender, age, area, smoking and pathology of patients who were initial diagnosed lung cancer and ancestral or permanent residence of hunan province in 1997 and 2007. Methods Clinical data of 908 patients with primary lung cancer hospitalized in Xiangya hospital were collected and evaluated. Results Compared patients in 2007 with those in 1997, ratio between male and female dropped from 3.8:1 to 2.98:1, while the proportion of young patients who were under 40 years old raised from 4.4% to 8.6% (χ2=4.465, P=0.035), patients living in the county raised from 19.9% to 40.1% (χ2=30.670, P < 0.001), smoking rate of patients from county raised from 16.9% to 39.9% (χ2= 24.939, P < 0.01). In addition, the proportion of rare histological types of lung cancer were also increased from 1.3% to 4.5% (χ2= 5.142, P=0.023). Conclusion Female patients, young patients, rural patients and rare histological types of lung cancer may have a tendency of increase in hunan province in recent years, whereas smoking cessation education should be strengthened