Learning from the past: uncovering design process models using an enriched process mining

Design documents and design project footprints accumulated by corporate IT systems have increasingly become valuable sources of evidence for design information and knowledge management. Identification and extraction of such embedded information and knowledge into a clear and usable format will greatly accelerate continuous learning from past design efforts for competitive product innovation and efficient design process management in future design projects. Different from existing systems, this paper proposes a methodology of learning and extracting useful knowledge using past design project documents from design process perspective based on process mining techniques. A new process mining approach that is able to directly handle textual data is proposed at the first stage of the proposed methodology. The outcome is a hierarchical process model that reveals the actual design process hidden behind a large amount of design documents and enables the connection of various design information from different perspectives. At the second stage, the discovered process model is further refined to learn multi-faceted knowledge patterns by applying a number of statistical analysis methods. The outcomes range from task dependency study from workflow analysis, identification of irregular task execution from performance analysis, cooperation pattern discovery from social net analysis, to evaluation of personal contribution based on role analysis. Relying on the knowledge patterns extracted, lessons and best practices can be uncovered which offer great support to decision makers in managing any future design initiatives. The proposed methodology was tested using an email dataset from a university-hosted multi-year multidisciplinary design project

2.5D multizone reproduction using weighted mode matching: Performance analysis and experimental validation

Mode-matching based multizone reproduction has been mainly focused on a purely two-dimensional (2D) theory, where infinite-long 2D secondary sources are assumed for 2D multizone reproduction. Its extension to the three-dimensional (3D) case requires more secondary sources and a higher computational complexity. This work investigates a more practical setup to use 3D sound sources as secondary sources for multizone reproduction in a 2D horizontal plane, i.e., 2.5D multizone reproduction. A weighted mode-matching approach is proposed to solve the dimensionality mismatch between the 2D desired sound field and 3D reproduced sound field. The weighting is based on an integral of Bessel-spherical harmonic modes over the entire control region. A detailed analysis of the weighting function is provided to show that the proposed method controls all the reproduction modes present on the 2D plane to minimize the reproduction error. The method is validated in both simulation-based and hardware-based experiments. The results demonstrate that in comparison with the conventional sectorial mode-matching method, the proposed approach can achieve more accurate reproduction over a wide frequency range and a large control region. 2020 Acoustical Society of America.This work was supported by the National Natural Science Foundation of China (NSFC) funding scheme under Project No. 61671380

Climate drives global soil carbon sequestration and crop yield changes under conservation agriculture

This research was supported by the Natural Science Foundation of China (grant Nos. 41530533 and 41573069) and the National Key R&D Program of China (grant No. 2017YFE0104600). We thank Prof. Xuhui Lee in Yale University, Dr. Zhongkui Luo in Zhejiang University, Prof. Ben Smith in Lund University and Dr. Xunyu Hu in East China Inventory and Planning Institute, State Forestry and Grassland Administration for their helpful comments that led to the improvement of this paper.Peer reviewedPostprin

Perspective Chapter: Organizational Ecology: Evolving Realities in Higher Education from Cholera to Covid - A Michigan State University Planning and Design Case Study

This manuscript is a narrative concerning the evolution of Michigan State University (MSU), the first American Land-grant school and the development of planning and design instruction and research at MSU from the 1860s until the present time, including adaptations in the post-Covid era. Covid is not the first epidemic to influence higher education at MSU, as the school had to adapt to Cholera (1832–1866), Scarlet Fever (1858), Typhoid Fever (1906–1907), H1N1 Flu (1918), Diphtheria (1921–1925), Polio (1916–1955), H2N2 Flu (1957), Second Measles Outbreak (1981–1991), H1M1 Flu (1991), Meningitis (1997 to present), Whooping Cough (2010, 2014), HIV and Aids (1980 to present), and Covid (2020 to present). The narrative presents a depiction of the changing organizational structure/network over time, illustrating the transformations in the sciences, arts, funding, and publication demands with comments, observations, and insights offered by Dr. Burley, FASLA, a now retired MSU landscape architecture faculty member with questions posed by the coauthors. The paper is in the form of traditional historic criticism essays meant to interpret events and activities. To critique does not have negative intent, but rather to bring understanding. The paper illustrates the transition from a German academic model to a diversified free-form education model

Global variations and drivers of nitrous oxide emissions from forests and grasslands

Nitrous oxide (N2O) emissions are highly variable due to the complex interaction of climatic and ecological factors. Here, we obtained in-situ annual N2O emission flux data from almost 180 peer-papers to evaluate the dominant drivers of N2O emissions from forests and unfertilized grasslands at a global scale. The average value of N2O emission fluxes from forest (1.389 kg Nha-1yr-1) is almost twice as large as that from grassland (0.675 kg Nha-1yr-1). Soil texture and climate are the primary drivers of global forest and grassland annual N2O emissions. However, the best predictors varied according to land use and region. Soil clay content was the best predictor for N2O emissions from forest soils, especially in moist or wet regions, while soil sand content predicted N2O emissions from dry or moist grasslands in temperate and tropical regions best. Air temperature was important for N2O emission from forest, while precipitation was more efficient in grassland. This study provides an overall understanding of the relationship between natural N2O emissions and climatic and environmental variables. Moreover, the identification of principle factors for different regions will reduce the uncertainty range of N2O flux estimates, and help to identify region specific climate change mitigation and adaptation strategies

Effect of growth temperature on the morphology and phonon properties of InAs nanowires on Si substrates

Catalyst-free, vertical array of InAs nanowires (NWs) are grown on Si (111) substrate using MOCVD technique. The as-grown InAs NWs show a zinc-blende crystal structure along a < 111 > direction. It is found that both the density and length of InAs NWs decrease with increasing growth temperatures, while the diameter increases with increasing growth temperature, suggesting that the catalyst-free growth of InAs NWs is governed by the nucleation kinetics. The longitudinal optical and transverse optical (TO) mode of InAs NWs present a phonon frequency slightly lower than those of InAs bulk materials, which are speculated to be caused by the defects in the NWs. A surface optical mode is also observed for the InAs NWs, which shifts to lower wave-numbers when the diameter of NWs is decreased, in agreement with the theory prediction. The carrier concentration is extracted to be 2.25 × 1017 cm-3 from the Raman line shape analysis. A splitting of TO modes is also observed