A breakdown voltage model for implanted resurf p-LDMOS device on n+ buried layer

This paper presents an analytical expression of the breakdown voltage of a high voltage implanted RESURF p-LDMOS device which uses the n+ buried layer as an effective device substrate. In this model, the doping profile of the buried layer is considered and discussed. The implant dose for the drift region to implement the RESURF principle is also described by this model. Results calculated from this model are verified by experimental values

Quantitatively Analyzing Phonon Spectral Contribution of Thermal Conductivity Based on Non-Equilibrium Molecular Dynamics Simulation II: From Time Fourier Transform

From nano-scale heat transfer point of view, currently one of the most interesting and challenging tasks is to quantitatively analyzing phonon mode specific transport properties in solid materials, which plays vital role in many emerging and diverse technological applications. It has not been so long since such information can be provided by the phonon spectral energy density (SED) or equivalently time domain normal mode analysis (TDNMA) methods in the framework of equilibrium molecular dynamics simulation (EMD). However, until now it has not been realized in non-equilibrium molecular dynamics simulations (NEMD), the other widely used computational method for calculating thermal transport of materials in addition to EMD. In this work, a computational scheme based on time Fourier transform of atomistic heat current, called frequency domain direct decomposed method (FDDDM), is proposed to analyze the contributions of frequency dependent thermal conductivity in NEMD simulations. The FDDDM results of Lennard-Jones (LJ) Argon and Stillinger-Weber (SW) Si are compared with TDNMA method from EMD simulation. Similar trends are found for both cases, which confirm the validity of our FDDDM approach. Benefiting from the inherent nature of NEMD and the theoretical formula that does not require any temperature assumption, the FDDDM can be directly used to investigate the size and temperature effect. Moreover, the unique advantage of FDDDM prior to previous methods (such as SED and TDNMA) is that it can be straightforwardly used to characterize the phonon frequency dependent thermal conductivity of disordered systems, such as amorphous materials. The FDDDM approach can also be a good candidate to be used to understand the phonon behaviors and thus provides useful guidance for designing efficient structures for advanced thermal management

The relation between black hole masses and Lorentz factors of the jet components in blazars

We explore the relation between black hole mass ($M_{\rm BH}$) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 146 blazars have reliable measurements on their apparent velocities of jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A significant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components, which the Eddington ratio is only weakly correlated with the minimal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.Comment: 18 pages, 5 figures, 3 tables, submitted to ChJA

REALIZING EFFICIENT USE AND CONSERVATION OF LAND UNDER PRIVATE OWNERSHIP: A REBUTMENT TO NOBEL ECONOMICS LAUREATE THEODORE W. SCHULTZ

Rebutting Theodore W. Schultz's assertions that small farmers are rational, low income countries saddled with traditional agriculture have not the problem of many farmers leaving agriculture for nonfarm jobs, part-time farming is efficient, and economies of scale have no logical basis and not stood the test of time, this paper presents that in (1) the low income countries still saddled with traditional agriculture, (2) the low income countries developing towards the high income economy, and (3) the high income countries, numerous able-bodied part-time and absent farmers earning higher off-farm income tend to under-utilize or idle small (and often fragmented) farms without selling or leasing them to full-time farmers to achieve economies of scale which do have logical basis and stood the test of empirical findings; and indicates that this is a global problem unresolved under private land ownership in both developing and developed countries. Thus small farmers in so doing are not so rational to the societal and their own fundamental interests. The paper also shows that in Central-Eastern Europe and Central Asia under private land ownership or possession many farmers voluntarily remain in collective land operation which perpetuates the low individual incentives. The paper further analyses the dilemmas the EU has been facing in resolving food overproduction, reducing trade-distorting agricultural subsidies and tariffs, keeping self-sufficiency, retaining small farmers in agriculture while strengthening large farmers, and efficient land use; and the crucial imperfections in the EU enlargement process. The paper thus proposes possible solutions on how to protect private land ownership, while transferring under-utilized land to full-time farmers; prevent the high costs of the traditional land consolidation, but still reaching its aims; keep part-time small farmers in agriculture, meanwhile bolstering full-time large farmers; avoid collective land operation, in the meantime benefiting from collective services; boosting EU enlargement but not adding burdens on the EU; retain non-cereal agriculture on ecologically sensitive land, at the same time improving the environment and precluding food overproduction; reduce trade-distorting agricultural subsidies and high tariffs, whereas making full-time farmers viable and competitive; and promote off-farm activities, for the meantime reinforcing agriculture.Land Economics/Use,

Overcoming Inefficient Land-Holding of Part-Time and Absent Small Farmers - A Challenge to Nobel Economics Laureate Theodore W. Schultz

Paper presented at the International Symposium Sustaining Food Security and Managing Natural Resources in Southeast Asia - Challenges for the 21st Century Organized by University of Hohenheim, Germany Chiang Mai University and Kasetsart University, Thailand International Center for Research in Agroforestry, and International Board for Soil Research and Management 8-11 January 2002 at Chiang Mai University, Thailandpart-time and absent small farmers, inefficient land-holding, low and high income economy, economies of scale, obliged lease of unused land to full-time farmers., Agricultural and Food Policy, Community/Rural/Urban Development, Farm Management, Food Security and Poverty, Institutional and Behavioral Economics, International Development, Labor and Human Capital, Land Economics/Use, Political Economy, Production Economics, Productivity Analysis, B, O, Q, R,

PRESERVING SMALL WHILE STRENGTHENING LARGE FARMERS IN THE USA AND OECD

Facing the general trend towards larger but fewer farms since 1935, the US government implemented a protective safety net for small farmers during 1933-96 which did not halt it but incurred market distortions and other drawbacks. It then switched to market oriented measures in 1996 which have made small farmers more exposed to market risks. A suitable solution to both preserving small and strengthening large farms has not been found. This paper provides a proposal not included in the 145 recommendations in the report `A Time to Act' by the National Commission on Small Farms of the USDA in January 1998: to promote part ownership of land by encouraging small farmers to develop off-farm activities and lease the land beyond self-need to part owners (including competent small farmers) to boost large farmers. In this way, while part owners could achieve economies of scale, small farmers would be boss of self-used land and landlord of rented-out land, integrated with large farmers, gain more income from rent, increase time for and earnings from off-farm activities, so that small farmers, rural communities, democracy roots and landscape could be conserved. It shows an example of how some black farmers who were small in terms of owned land but became large after renting in land achieved success in farming. Although part ownership has been increasing, it has never been promoted as a policy direction and even be neglected. This proposal may be relevant to other OECD countries with a large versus small bimodal farm structure.land tenure, full owner, tenant, part owner, large farmers, small farmers, off farm activities, inefficient land-holding, Dual Land System, Single Land System, Industrial Organization,