Residential Appraisal and the Lending Process: A Survey of Issues

This article surveys mainly academic literature for issues concerning the use of appraisals in the residential lending process. The development of appraisal methodologies is reviewed, and the strengths and weaknesses of various appraisal techniques are assessed. Issues relating to the use of neighborhood characteristics in appraisals for lending purposes are also explored. Finally, institutional incentives that give rise to biased and self-serving appraisals and possible solutions to these incentive problems are examined.

A Modified Boost Converter with Reduced Input Current Ripple

Battery-powered trends in consumer electronics, transportation, and renewable energy sectors increase demands on DC/DC converter technology. Higher switching frequency and efficiency reduces solution size and cost, while increasing power capabilities. Still, switching noise remains the primary drawback associated with any DC/DC converter. Reducing a converter’s input ripple helps prevent switching noise from spreading to other systems on a shared DC power bus. This thesis covers the analysis, simulation, and implementation of a recently-proposed boost converter topology, alongside an equivalent standard boost converter, operating in steady-state, continuous conduction mode. A Matlab-based simulation predicts each converter’s input ripple performance using a state-space model. The converters’ hardware implementation minimizes component and layout differences to create an equivalent comparison. The simulation and hardware measurements demonstrate a 40% input current ripple reduction using the modified topology. Replacing standard boost converters with the modified topology minimizes the switching noise conducted through a system’s DC power network

A Case of Reactive Cervical Lymphadenopathy with Fat Necrosis Impinging on Adjacent Vascular Structures.

A tender neck mass in adults can be a diagnostic challenge due to a wide differential diagnosis, which ranges from reactive lymphadenopathy to malignancy. In this report, we describe a case of a young female with an unusually large and tender reactive lymph node with fat necrosis. The diagnostic imaging findings alone mimicked that of scrofula and malignancy, which prompted a complete workup. Additionally, the enlarged lymph node was compressing the internal jugular vein in the setting of oral contraceptive use by the patient, raising concern for Lemierre's syndrome or internal jugular vein thrombosis. This report shows how, in the appropriate clinical context, and especially with the involvement of adjacent respiratory or neurovascular structures, aggressive diagnostic testing can be indicated

Intra-Project Externality and Layout Variables in Residential Condominium Appraisals

This study examines the impact of intra-project externalities and layout variables on the selling prices of 897 condominium units in the cities of Irvine and Santa Ana in Orange County, California. It documents that, at a micro-level, proximity to intra-project externalities such as greenspace, swimming pools, recreational areas, traffic noise, and the like, and project layout variables representing the location of individual condominium units within multiunit structures, have significant effects on the property values of units within a condominium project. The results indicate that, when cost is not prohibitive, both appraisers and underwriters should take intra-project externalities and layout variables into consideration when estimating property values or underwriting residential mortgages for condominium properties.

Buoyancy arrest and bottom Ekman transport. Part I : steady flow

Author Posting. © American Meteorological Society, 2010. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 40 (2010): 621-635, doi:10.1175/2009JPO4266.1.It is well known that along-isobath flow above a sloping bottom gives rise to cross-isobath Ekman transport and therefore sets up horizontal density gradients if the ocean is stratified. These transports in turn eventually bring the along-isobath bottom velocity, hence bottom stress, to rest (“buoyancy arrest”) simply by means of the thermal wind shear. This problem is revisited here. A modified expression for Ekman transport is rationalized, and general expressions for buoyancy arrest time scales are presented. Theory and numerical calculations are used to define a new formula for boundary layer thickness for the case of downslope Ekman transport, where a thick, weakly stratified arrested boundary layer results. For upslope Ekman transport, where advection leads to enhanced stability, expressions are derived for both the weakly sloping (in the sense of slope Burger number s = αN/f, where α is the bottom slope, N is the interior buoyancy frequency, and f is the Coriolis parameter) case where a capped boundary layer evolves and the larger s case where a nearly linearly stratified boundary layer joins smoothly to the interior density profile. Consistent estimates for the buoyancy arrest time scale are found for each case.This research was supported by the National Science Foundation Physical Oceanography program through Grant OCE 0647050

Buoyancy arrest and bottom Ekman transport. Part II : oscillating flow

Author Posting. © American Meteorological Society, 2010. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 40 (2010): 636-655, doi:10.1175/2009JPO4267.1.The effects of a sloping bottom and stratification on a turbulent bottom boundary layer are investigated for cases where the interior flow oscillates monochromatically with frequency ω. At higher frequencies, or small slope Burger numbers s = αN/f (where α is the bottom slope, N is the interior buoyancy frequency, and f is the Coriolis parameter), the bottom boundary layer is well mixed and the bottom stress is nearly what it would be over a flat bottom. For lower frequencies, or larger slope Burger number, the bottom boundary layer consists of a thick, weakly stratified outer layer and a thinner, more strongly stratified inner layer. Approximate expressions are derived for the different boundary layer thicknesses as functions of s and σ = ω/f. Further, buoyancy arrest causes the amplitude of the fluctuating bottom stress to decrease with decreasing σ (the s dependence, although important, is more complicated). For typical oceanic parameters, arrest is unimportant for fluctuation periods shorter than a few days. Substantial positive (toward the right when looking toward deeper water in the Northern Hemisphere) time-mean flows develop within the well-mixed boundary layer, and negative mean flows exist in the weakly stratified outer boundary layer for lower frequencies and larger s. If the interior flow is realistically broad band in frequency, the numerical model predicts stress reduction over all frequencies because of the nonlinearity associated with a quadratic bottom stress. It appears that the present one-dimensional model is reliable only for time scales less than the advective time scale that governs interior stratification.This research was sponsored by the National Science Foundation, Physical Oceanography Program through Grant OCE 0647050