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中国畜牧杂志 2009年第24期45卷 45-50页

作者：武书庚(译) 程宗佳(校) carl e．polan 中国农业科学院饲料研究所北京100081 美国大豆出口协会北京100004 不详

随着奶牛单产水平的提高，其日粮中粗蛋白（CP）的推荐水平也在增加，现在高产奶牛日粮的CP甚至达到18％。整群奶牛饲喂全混日粮，可能会导致部分奶牛的蛋白摄入高出实际需要，而增加日粮CP会降低氮的利用率，并增加粪氮的排泄量。

关键词：蛋白资源氨基酸需要泌乳牛奶牛日粮评价单产水平全混日粮奶牛饲喂

Post-mining policies and practices in the eastern USA coal region

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International Journal of Coal Science & Technology 2014年第2期1卷 135-151页

作者： Jeff Skousen carl e.Zipper West Virginia University MorgantownWV 26506USA Virginia Polytechnic Institute and State University BlacksburgVA 24061USA

Surface coal mines prior to 1950 in the USA were generally left without any *** government regulations advanced since then,mine operators were required to backfill the area and plant grasses or *** the federal Surface Mining Control and Reclamation Act(SMCRA)was passed in 1977 in the USA,mine operators were required to conduct pre-mining analyses of the site and to designate a land use that could be achieved after *** reclamation,as needed to satisfy today’s societal demands,requires engineering,design,and purposeful reconstruction of the full mining disturbance,not just its surface,and control of waters leaving the mine *** reclamation on modern American coal mines is fully integrated with the mining operation.A suitable and effective postmining land use that is sustainable for future generations is crucial to the long-term success and profitability of the mining business and to the future economic benefits of the *** post-mining land uses in the USA are:(1)prime farmland,(2)hay land and pasture,(3)biofuel crops,(4)forestry,(5)wildlife habitat,and(6)building site *** and regulations for each post-mining land use were developed and practices to achieve successful and sustainable land uses were ***-mining conditions should provide ecosystem services and produce lands capable of supporting societal needs in the future.

关键词： Biofuel Commercial development Laws and regulations Pasture Prime farmland Reforestation Water quality Wildlife habitat

Situation analytics—at the dawn of a new software engineering paradigm

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Science China(Information Sciences) 2018年第5期61卷 5-18页

作者： carl K.CHANG Department of Computer Science Iowa State University

In this paper, I first review the seminal work by Thomas Kuhn — The Structure of Scientific Revolutions — and elaborate my view on paradigm shifts in software engineering research and practice as it turns 50 years old in 2018. I then examine major undertakings of the computing profession since early days of modern computing, especially those done by the software engineering community as a whole. I also enumerate anomalies and crises that occurred at various stages, and the attempts to provide solutions by the software engineering professionals in the past five decades. After providing such a background, I direct readers’ attention toward emerging anomalies in software engineering, at a severity level that is causing another software engineering crisis, and suggest a set of criteria for feasible solutions. The main theme of this paper is to advocate that situation analytics, equipped with necessary definitions of essential concepts including situation and intention as parts of a new computational framework, can serve as the foundation for a new software engineering paradigm named the Situation-Centric Paradigm. In this framework, situation is considered a new abstraction for computing and is clearly differentiated from the widely accepted existing abstractions, namely function and object. I argue that the software engineering professionals will inevitably move into this new paradigm, willingly or unwillingly, to empower Human-embedded Computing(HeC) and end-User embedded Computing(eUeC), much more than what they have done with traditional humancentered or user-centric computing altogether. In the end, I speculate that an ultimate agile method may be on the rise, and challenge readers to contemplate "what if" hundreds of thousands "end-user developers"emerge into the scene where the boundaries between end users and developers become much more blurred.

关键词： ultimate agile method context intention Internet of things paradigm situation software engineering human-embedded computing

Diffusion in the Lorentz Gas

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Communications in Theoretical Physics 2014年第10期61卷 521-540页

作者： carl P.Dettmann School of Mathematics University of BristolBristol BS8 1TWUK

The Lorentz gas, a point particle making mirror-like reflections from an extended collection of scatterers,has been a useful model of deterministic diffusion and related statistical properties for over a century. This survey summarises recent results, including periodic and aperiodic models, finite and infinite horizon, external fields, smooth or polygonal obstacles, and in the Boltzmann–Grad limit. New results are given for several moving particles and for obstacles with flat points. Finally, a variety of applications are presented.

关键词： Lorentz gas ehrenfest wind-tree model conductivity diffusion Burnett coefficients

Out-of-core clustering of volumetric datasets

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2006年第7期7卷 1134-1140页

作者： GRANBeRG carl J. Department of Computing Curtin University of Technology Perth Australia

In this paper we present a novel method for dividing and clustering large volumetric scalar out-of-core datasets. This work is based on the Ordered Cluster Binary Tree (OCBT) structure created using a top-down or divisive clustering method. The OCBT structure allows fast and efficient sub volume queries to be made in combination with level of detail (LOD) queries of the tree. The initial partitioning of the large out-of-core dataset is done by using non-axis aligned planes calculated using Principal Component Analysis (PCA). A hybrid OCBT structure is also proposed where an in-core cluster binary tree is combined with a large out-of-core file.

关键词： Out-of-core clustering Hybrid rendering Scientific visualization

Scaling granular material with polygonal particles in discrete element modeling

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Particuology 2023年第4期75卷 151-164页

作者： Alireza Ahmadi Stefan Larsson carl Wersall KTH Royal Institute of Technology Division of Soil and Rock MechanicsBrinellvagen 2310044StockholmSweden

Despite advancements in computational resources,the discrete element method(DeM)still requires considerable computational time to solve detailed problems,especially when it comes to the large-scale *** addition to the geometry scale of the problem,the particle shape has a dramatic effect on the computational cost of ***,many studies have been performed with simplified spherical particles or *** scaling is an approach to increase the particle size to reduce the number of particles in the *** several particle scaling methods have been introduced,there are still some disagreements regarding their applicability to certain aspects of *** this study,the effect of particle scalping on the shear behavior of granular material is *** granular particles were scanned and imported as polygonal particles in the direct shear *** effect of particle size distri-bution,particle angularity,and the amount of scalping were *** results show that particle scalping can simulate the correct shear behavior of the model with significant improvement in computational ***,the accuracy of the scalping method depends on the particle angularity and particle size range.

关键词： Particle scaling Direct shear test Discrete element method PFC Polygonal shape Granular material

Multitemporal landslide inventory analysis of an intertropical mountain in west-central Mexico——Basis for hazard management

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Journal of Mountain Science 2022年第6期19卷 1650-1669页

作者： Alejandro Cesar VALDeS CARReRA Manuel e.MeNDOZA Teodoro carlÓN ALLeNDe Jose Luis MACIAS Centro de Investigaciones en Geografia Ambiental Universidad Nacional Autonoma de MexicoMorelia 58190Mexico Consejo Nacional de Ciencia y Tecnologia-Instituto de Geofisica-Unidad Michoacan Universidad Nacional Autonoma de MexicoMorelia 58190Mexico Instituto de Geofisica-Unidad Michoacan Universidad Nacional Autonoma de MexicoMorelia 58190Mexico

Landslides in intertropical mountainous areas of Mexico are a natural hazard that could potentially generate a disaster. Despite this, many areas lack landslide inventories, making it difficult to monitor and efficiently manage the associated risks for local populations. For this reason, the aim of this research was to undertake a multitemporal landslide inventory and analyze its conditioning factors in the Pico de Tancítaro stratovolcano, which, in recent decades, has presented several high-risk geomorphological events with disastrous consequences for nearby localities. The spatial distribution of landslides and its conditioning factors were mapped at a 1:50,000 scale for the 1995-2020 period, through visual interpretation of orthophotos and satellite images(Landsat, SPOT, and SeNTINeL). The conditioning factors that link the most to landslides were Quaternary andesite and basaltic andesite rocks;volcanic cones, mountain river valleys, and very steep to steep slopes(30° to >45°), oriented to the South, North, and east;Andosols and Leptosols;and the oyamel fir and mixed forests. 505 landslide events classified into slides and flows that occurred in 1995, 2004, 2010, and 2015 were identified. New scars generated by the reactivation of landslide processes were also observed. The landslides in the study area were triggered by torrential rains caused by hurricanes and tropical storms;such as hurricanes Alex and Patricia. The inventory and analysis of conditioning factors highlighted the distribution and dynamics of slides and flows in the study area. In addition, the most important factors for studies of landslide susceptibility, hazards, and risks in the Pico de Tancítaro stratovolcano were identified, contributing to the management of geomorphological risks in intertropical mountain areas.

关键词： Geomorphology Mass wasting Natural hazards Pico de Tancítaro stratovolcano Risk management

Improved dynamic testing by impedance control

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earthquake engineering and engineering Vibration 2011年第3期10卷 423-435页

作者： Jochen carl Mettupalayam V. Sivaselvan Department of Civil Environmental and Architectural EngineeringUniversity of Colorado at Boulder

In this paper, the issue of actuator-structure interaction in dynamic testing of structures is considered. The problem is approached from the novel standpoint of impedance control. It is shown that an effective strategy to design controls for dynamic testing is by designing the test system impedance. It is also shown that this can be achieved using feedforward compensation. The analysis is carried out in the context of displacement controlled dynamic testing, when the tested structure has a high and nonlinear stiffness. It is demonstrated that stable and accurate dynamic testing can be achieved using the proposed strategy, when this is not possible using traditional feedback control techniques. Furthermore, the impedance control and feedforward strategies are applied in the context of hybrid simulation, a technique of coupling computational and physical substructures applied in earthquake engineering. Here, a delay compensation scheme is necessary in addition to feedforward. experimental results are presented that demonstrate both improved dynamic testing performance when impedance control is employed, and its applicability in hybrid simulation.

关键词： dynamic test actuator-structure interaction impedance control hybrid simulation feedforward strategy

Impact of weather conditions and building design on contaminant infiltration from crawl spaces in Swedish schools-Numerical modeling using Monte carlo method

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Building Simulation 2022年第5期15卷 845-858页

作者： Fredrik Domhagen Paula Wahlgren carl-eric Hagentoft Department for Architecture and Civil engineering Division of Building TechnologyChalmers University of TechnologySE-41296GothenburgSweden

Some Swedish school buildings built in the 1960s and 1970s experience indoor air quality problems,where the contaminants are suspected to come from the crawl space underneath the *** poor indoor air quality causes discomfort among pupils and *** an exhaust fan to maintain a negative pressure difference in the crawl space relative to indoors or increasing the ventilation in the classroom are two examples of common measures taken to improve the indoor air ***,these measures are not always effective,and sometimes the school building has to be *** relation between pressure distribution,contaminant concentration in the classroom,outdoor temperature,wind,mechanical ventilation,and air leakage distribution is complex.A better understanding of these relations is crucial for making decisions on the most efficient measure to improve the indoor air *** this paper,a model for contaminant infiltration from the crawl space is used together with the Monte carlo method to study these *** are performed for several cases where different building shapes,building orientations,shielding conditions,and geographical locations are *** show,for example,that for a building with an imbalanced ventilation system,air is leaking from the crawl space to the classroom for the majority of cases and that concentration levels in the classroom are usually the highest during mild and calm days.

关键词： airtightness air permeability Monte carlo method infiltration model crawl space indoor air quality

The Determinants of Plant Variety Protection Applications in China

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中国人口·资源与环境(英文版) 2007年第2期5卷 53-62页

作者： carl Pray Department of Agricultural Food and Resource economics Rutgers University NJ 08901-8520 USA

China passed its Plant Variety Protection Act (PVPA) in 1997 which allowed us to do some initial testing of this proposition. We used a unique dataset on the applications of the new Plant Variety Protection (PVP), morphological characteristics, and institutional sources of all the important varieties of rice in three provinces of China to estimate the determinants of plant variety protection applications in China. The evidence suggests that both the government and private research programs are responding to economic and policy incentives and investing in plant variety protection as economists would expect profit maximizing firms to invest. The discussion of the evolution of the seed industry suggested that the combination of the new seed law in 2000 and the new plant variety protection regulation had changed the structure of the seed industry and provided an important incentive to invest in PVPs both by public research institutes and commercial firms. Finally, there is some preliminary evidence that private firms have smaller incentives to develop new varieties than to purchase the new varieties.

关键词： Application China Crop Protection Variety