knowledgebased product development the 3D CAD model of knowledge creationWord格式文档下载.docx

1、 AbstractAbstract | Figures/TablesFigures/Tables | ReferencesReferences AbstractSmall towns across the southern Piedmont of North Carolina are experiencing rapid growth and encroachment from larger neighboring municipalities. Many of these communities are confronted with the tough issue of preservin

2、g the quality of the environment, while at the same time allowing development to occur. Greenways are an excellent mechanism that balances needs for both conservation and growth. Once considered to be just a vegetated linear area for preventative purposes, greenways have evolved into a resource that

3、 can meet the publics needs for recreation, environmental protection, and alternative transportation. There has also been a shift of focus in greenway planning: from a single-objective paradigm of environmental protection or natural conservation to a multi-objective process that allocates greenways

4、as a resource to satisfy the publics demands for all three benefits. However, these exciting developments bring a serious challenge to greenway planners: how to delineate future greenway corridors so that all the many functions are properly incorporated and the potential benefits are maximized?In th

5、is paper we demonstrate, through a project for the City of Concord, North Carolina, that such a challenge can be met by using a systematic approach to greenway planning. With this approach, we identified future greenway corridors within the City of Concord that best serve the multiple objectives of

6、environmental protection, recreation, and alternate transportation. These alternative greenway scenarios will later be used by the local communities, public officials, and planners as an information basis in their pursuit of a well-connected and balanced land development in the city. It is hoped tha

7、t the results will be integrated into the citys comprehensive land use plan.Article Outline1. Introduction2. A methodology for greenway planning 2.1. Identification of goals and objectives2.2. Assessment of potential demand areas2.3. Assessment of potential connectivity supplies2.4. Assessment of si

8、te suitability2.5. Assessment of accessibility2.6. Delineation of corridors2.7. Evaluation3. Implementation of the methodology 3.1. Identification of goals and objectives3.2. Assessment of demand areas3.3. Assessment of potential connectivity supplies3.4. Assessment of site suitability 3.4.1. Locati

9、on within the floodplain3.4.2. Soil suitability for paths and trails3.4.3. Proximity to sewer line easements3.4.4. Parcel size3.4.5. Land ownership3.4.6. Future land use3.4.7. Existing development3.5. Assessment of accessibility3.6. Delineation of corridors3.7. Evaluation4. Results and discussion 4.

10、1. The Three Mile Branch corridor4.2. The Coddle Creek/Afton Run loop4.3. The Rocky River/Clarke Creek corridor5. ConclusionsAcknowledgementsReferencesVitaePurchase$ 41.95182Evaluating the learning process of mechanical CAD studentsComputers & Education, Volume 49, Issue 3, November 2007, Pages 640-

11、661R.F. Hamade, H.A. Artail, M.Y. JaberThere is little theoretical or experimental research on how beginner-level trainees learn CAD skills in formal training sessions. This work presents findings on how trainees develop their skills in utilizing a solid mechanical CAD tool （Pro/Engineer version 200

12、0i2 and later version Wildfire）. Exercises at the beginner and intermediate levels were designed so that several variations of a solid object are built by non-experienced trainees as they accumulate training time. In this case, trainees are fourth year mechanical engineering seniors and as such, the

13、y were of a similar technical and gender make-up. This assessment was conducted over the duration of training （16-week long semester）. The test exercises were used to assess the trainees speed and proficiency in the use of CAD by （1） measuring their performance time and （2） feature count （number of

14、features-of-size used to build the test parts）. Using performance time data, empirical learning curves are generated. Breaking these curves into declarative and procedural components provides insight into how fast the trainees develop cognitive and motor CAD skills. In order to confirm that this met

15、hodology can be extended to other CAD platforms, a follow-up study was performed on a different set of beginner-level trainees with similar make-up while using the same beginner-level parts but with a more recent version of Pro/Engineer: Wildfire. One significant result of this study is that the pro

16、cedural and declarative components of CAD learning are largely cognitive.2. Background and objectives3. Methodology4. Training description and assessment results 4.1. Version 2000i2 4.1.1. Stage 1 （Beginner-level test parts） learning assessment 4.1.1.1. Feature-build plans4.1.1.2. Performance analys

17、is4.1.2. Stage 2 （intermediate-level test parts） learning assessment4.2. Version wildfire5. Discussion 5.1. Version 2000i25.2. Version wildfire6. Conclusions$ 24.95183Mapping private gardens in urban areas using object-oriented techniques and very high-resolution satellite imageryLandscape and Urban

18、 Planning, Volume 81, Issue 3, 20 June 2007, Pages 179-192Renaud Mathieu, Claire Freeman, Jagannath AryalGardens remain the least studied and least understood habitat in urban areas. With the recent exception of the URGENT funded urban domestic gardens project in the UK, there is a notable lack of r

19、esearch on the ecological character and contribution of gardens to the wider urban biodiversity. This is despite the fact that gardens usually comprise the largest vegetated component of the urban greenspace resource. In part this omission has been due to the difficulties inherent in obtaining ecolo

20、gical data on gardens and the lack of a methodology for classifying and analysing garden data. This paper presents data from a study undertaken in the city of Dunedin, New Zealand. The study developed a methodology using object-oriented classification techniques and very high-resolution multispectra

21、l Ikonos imagery to automatically map the extent, distribution and density of private gardens in the city. The focus was on the vegetated garden area which was calculated as comprising 46% of the residential area or 36% of the total urban area. Rigorous accuracy assessments were undertaken. When usi

22、ng the automated classification technique, a total of 90.7% of the private gardens were correctly identified. Discrimination of garden types （e.g. trees or grass dominated） was encouraging, but still requires improvement. Our results indicate the great potential that the methodology has in providing

23、 a quick method for obtaining good quality ecological data on garden habitats in urban areas.2. The contribution of gardens to urban ecology3. Habitat mapping in urban areas4. Private garden mapping 4.1. Study area4.2. Object-oriented classification4.3. Ikonos imagery4.4. Garden extraction 4.4.1. Le

24、vel one, classification into four classes4.4.2. Level two, classification into six classes4.5. Accuracy assessment5. Results 5.1. Garden map accuracy assessment5.2. Private garden resources6. Discussion 6.1. Mapping accuracy6.2. Relevance of the private garden dataset184Urban gardens: Lead exposure,

25、 recontamination mechanisms, and implications for remediation designEnvironmental Research, Volume 107, Issue 3, July 2008, Pages 312-319Heather F. Clark, Debra M. Hausladen, Daniel J. BrabanderEnvironmental lead contamination is prevalent in urban areas where soil represents a significant sink and

26、pathway of exposure. This study characterizes the speciation of lead that is relevant to local recontamination and to human exposure in the backyard gardens of Roxbury and Dorchester, MA, USA. One hundred forty-one backyard gardens were tested by X-ray fluorescence, and 81% of gardens have lead leve

27、ls above the US EPA action limit of 400g/g. Raised gardening beds are the in situ exposure reduction method used in the communities to promote urban gardening. Raised beds were tested for lead and the results showed that the lead concentration increased from an initial range of 15040g/g to an averag

28、e of 336g/g over 4 years. The percent distribution of lead in the fine grain soil （100m） and the trace metal signature of the raised beds support the conclusion that the mechanism of recontamination is wind-transported particles. Scanning electron microscopy and sequential extraction were used to characterize the speciation of lead, and the trace metal signature of the fine grain soil in both gardens and raised gardening beds is characteristic of lead-based paint. This study demonstrates that raised beds are a limited exposure