Analysis of the Effects of Large Lot Zoning

This study extends a test for the presence of binding zoning, originally developed to be applied across many adjacent jurisdictions, so that it can be applied within a single jurisdiction. This study also demonstrates how to carry out this test in the presence of spatially correlated OLS residuals by using a mixed effects model whose coefficients are estimated using the maximum likelihood technique. The study examines twenty years of land sales data from a Midwestern county containing two adjacent cities surrounded by rural areas. A thirty-five-acre acre, minimum lot size in the rural area is found to be binding; while a 9,000 square foot minimum lot size in the cities is found to be not binding.

An Empirical Analysis of the Determinants of the Value of Vacant Land

This study extends the literature that investigates the use of buyer and seller characteristics in traditional hedonic price equation regressions. This study adds to the existing literature on the relationship between parcel size and price, coined plattage by Colwell and Sirmans (1980). The results reveal statistically significant buyer and seller effects. Also, the results confirm the existence of the plattage effect and reveal a statistically significant change in the plattage effect over time. The findings of this study should prove useful to those interested in the behavior of land markets on an urban fringe.

The Linear Algebra of the Sales Comparison Approach

This study presents the sales comparison approach to value as a system of linear algebra equations. The difference between appraiser and academician views of this system of equations is shown to pivot on the one-price assumption. The need of appraisers to subjectively derive adjustment factors is shown to be an artifact of the common practice of appraisers to assume multiple indicated values. The use of multiple regression analysis and other statistical techniques by academicians is shown to be possible only given the one-price assumption. Suggestions are presented for the improvement of both views.

Uprooting Diversity? Peasant Farmers’ Market Engagements and the on-Farm Conservation of Crop Genetic Resources in the Guatemalan Highlands

The long-term security of the global food supply is contingent upon the on-farm conservation of crop genetic diversity. Without it, food crops lack the ability to evolve in the face of new pests, emerging plant diseases, and changing environmental conditions. The genetic diversity of many of humankind’s major food crops is cultivated in the field, primarily by peasant farmers of the global south. As the widening of global markets affects the lives of these farmers in new ways, the future provisioning of crop genetic resources and, ultimately, the security of the global food supply is in doubt. The author investigates how the participation of Guatemalan peasants in the market economy is related to the on-farm conservation of crop genetic diversity in three crops: maize, legumes, and squash. Participation in markets is not inherently detrimental to the provisioning of crop genetic resources but, without the proper protections in place, market participation may unleash processes that contribute to genetic erosion over time. The author concludes by sketching seven policy prescriptions that would encourage the on-farm conservation of crop genetic diversity in a way that is consistent with peasant farmers’ development objectives.crop genetic resources, peasant agriculture, food security, market integration, Guatemala

The Effect Of Roughness On Bottom Loss From Elastic Ocean Bottoms

Acoustic interaction with the ocean bottom profoundly affects propagation in shallow waters. However, most forward ocean bottom interactions are modeled as if the bottom were a flat interface or use a simple model to quantify the additional loss. These assumptions either neglect or over-estimate the enhancement of ocean bottom loss due to scattering into the bottom. Scattering from and into elastic bottoms is particularly interesting since it can induce the production of an interface wave. In this study, finite element analysis is used to calculate acoustic scattering from elastic ocean bottoms with varying degrees of roughness. The forward scattering loss from these bottoms is calculated as a function of angle and then compared with the flat bottom reflection coefficient in order to gain insight on the conditions under which enhancement of bottom loss by rough interface scattering is significant.Applied Research Laboratorie

Wave Propagation In Water-Saturated Sand And Grain Contact Physics

Measurements in sandy ocean sediments over a broad range of frequencies show that the sound speed dispersion is significantly greater than that predicted by the Biot-Stoll model with constant coefficients, and the observed sound attenuation does not seem to follow a consistent power law. The observations may be explained in terms of the Biot-Stoll model with frequency-dependent complex frame bulk and shear moduli that are governed by the grain-grain contact physics, and random motion at the grain level. In the case of water-saturated sands, the contact stiffness is dominated by squirt flow and viscous drag of a thin fluid film that permeates the contact area. Using this approach, the observed sound and shear wave speeds and attenuations may be modeled over a broad band of frequencies.Applied Research Laboratorie

The Evolution Of Sediment Acoustic Models

Sediment acoustic models contain two connected components, the geo-physical description of the sediment and the model of acoustic processes. Geo-physical descriptors are used in the classification of sediments, and they are based on grain size, density and other physical descriptors. Acoustic sediment models were initially fluid approximations that were simple to implement. As the need for accuracy increased, the fluid model was extended to stratified fluid and visco-elastic models. The latter, with five frequency-independent parameters, appeared to be consistent with sediment acoustic data up to the 1980s. More recent experimental data have revealed discrepancies in the frequency-dependence of attenuation and sound speed, particularly in the case of sandy sediments, which cover a large fraction of the continental shelves. Broad-band acoustic measurements of wave speeds and attenuations are more consistent with a poro-elastic model, consisting of Biot's theory with extensions to account for the physics of granular media. Aside from terminology, there is a fundamental difference between viscoelastic and poro-elastic theories. The former is based on two types of waves, a compressional wave and a shear wave, while the latter has an additional compressional wave, often called the Biot wave. There are currently two approaches to the development of sediment acoustic models: (a) visco-elastic models with frequency dependent parameters that mimic the observed behavior, and (b) poro-elastic models that reflect the physical processes. It is shown that (a) would be a significant improvement over existing models, but (b) is the preferred solution.Applied Research Laboratorie

Total Quality Management and Residential Real Estate Agency Issues

This study explores the implications of applying Total Quality Management (TQM) principles to residential real estate brokerage, specifically the need for customer focus. Deming's (1986) TQM system of fourteen points reduced to four distinct subsystems. The most critical of these is the need for customer focus. Several approaches to agency in residential real estate brokerage are presented, with an examination of the ease with which customer focus can be obtained with each approach. The main finding is that customer focus can be achieved easier with the agency specialization approach.

Yoga for children with cerebral palsy : mobility and muscle elasticity in the lower extremities

Background: Movement and posture are always affected in children with cerebral palsy (CP). Motor symptoms vary in degree and severity, however a decreased joint mobility in the lower extremities is common. With increasing age, the decreased range of motion becomes more prominent and can lead to further impairments. There is a lack of evidence for ordinary physiotherapeutic treatment methods in order to maintain and increase range of motion as well as to prevent decreased joint mobility. Aim: The aim was to evaluate if yoga exercises could influence the joint mobility, including the joint mobility symmetry, between the right and left side of the hip, knee and ankle, and also the muscle elasticity in the quadriceps and hamstrings muscles in children with cerebral palsy. Method: Twenty children with CP, aged 6-12 years, participated in the study. Yoga exercises were performed once a week for a period of 10 weeks. Passive range of motion in the hip joint (long and short abductors, external and internal rotators, and extensors), knee joint (extensors) and ankle joint (long and short dorsiflexors), together with muscle elasticity in the quadriceps and hamstrings muscles were measured with a goniometer before and after the period of yoga exercise. To describe symmetry in joint mobility between right and left extremity before and after yoga exercise Spearman’s correlation coefficient (rs) was used. Results: Among those 12 children who participated in more than seven sessions, muscle elasticity was significantly increased in the right (p<0.05) and also the left (p<0.01) quadriceps. Analysis of passive range of motion and muscle elasticity after yoga training demonstrated few significant differences. The correlation between passive range of motion in the right and left leg were higher after the yoga exercise period, preferably in the short abductors ( rs 0.84) than before (rs 0.52), and in the external rotators (after rs 0.75, and before rs 0.69). Conclusion: This study points out that yoga exercise could contribute to an increased symmetry in the hip joint mobility in children with CP. There is a need for further studies to evaluate the effect on passive range of motion and muscle elasticity after yoga training in this group.Bakgrund: Barn med cerebral pares har alltid en påverkan på motorik och balans. De motoriska symtomen varierar i typ och omfattning och inskränkt ledrörlighet i nedre extremiteterna är vanligt förekommande. Inskränkningarna ökar under uppväxtåren och kan i sin tur leda till ytterligare funktionsnedsättningar. Idag saknas evidens för sjukgymnastiska behandlingsmetoder för att förebygga, bibehålla och öka ledrörlighet. Syfte: Syftet var att undersöka om det fanns någon skillnad i ledrörlighet och symmetri i ledrörlighet mellan höger och vänster sida i höft-, knä- och fotleder samt elasticitet i quadricpes- och hamstringsmuskulatur hos barn med CP före och efter yogaträning. Metod: Tjugo barn med CP i åldern 6-12 år tränade yoga en gång i veckan vid 5-10 tillfällen. Passiv rörlighet i höftledens långa och korta abduktorer, utåt- och inåtrotatorer och flexorer, knäledens flexorer, fotledens långa och korta flexorer samt muskelelasticiteten i quadriceps- och hamstringsmuskeln mättes med goniometer före och efter yogaträningsperioden. För att beskriva symmetri i ledrörlighet mellan höger och vänster sidas extremitet före och efter yogaträningen användes Spearman’s rangkorrelationskoefficient, rs. Resultat: Hos de tolv barn som tränade mer än sju gånger visades en signifikant ökad muskelelasticitet i höger sidas (p<0.05) och vänster sidas (p<0..01) quadriceps. Korrelationen mellan ledrörligheten i höger och vänster ben var högre i höftledens korta abduktorer efter yogan (rs 0.84) jämfört med före (rs 0.52). och högre i höftledens utåtrotatorer efter yogan (rs 0.75) jämfört med före (rs 0.69). Analys av skillnader i passiv ledrörlighet och muskelelasticitet visade på få signifikanta skillnader. Konklusion: Studien visade att yogaträning kan bidra till ökad symmetri i höftleden hos barn med CP, men vidare studier behövs för att utvärdera effekten av passiv ledrörlighet och muskelelasticitet