bluuebunny/crossref_metadata_2025 huggingface dataset:
Crystal structures and band offsets of ultrathin HfO2–Y2O3 composite films studied by photoemission and x-ray absorption spectroscopies
Authors: Komatsu M. , Yasuhara R. , Takahashi H. , Toyoda S. , Kumigashira H. , Oshima M. , Kukuruznyak D. , Chikyow T.
Published: October 2006

The authors have investigated ultrathin HfO2–Y2O3 composite films by photoemission spectroscopy and x-ray absorption spectroscopy (XAS) to elucidate the Y2O3 composition dependence of crystallization and band offsets. The authors have found that the crystal structure of ultrathin films can be predicted by the detailed spectral structure between 540 and 550eV in XAS. Photoemission spectroscopy and XAS reveal that the films of x=0 and 0.05 are mainly in a monoclinic phase, while those of x=0.10 and 0.20 are in a cubic phase. Regardless of the crystal structure changes by adding Y2O3 to HfO2, the band gap and band offsets remain almost unchanged.
Structure and interface chemistry of perovskite-spinel nanocomposite thin films
Authors: Zhan Q. , Yu R. , Crane S. P. , Zheng H. , Kisielowski C. , Ramesh R.
Published: October 2006

The structure and the interface chemistry of epitaxial BiFeO3–NiFe2O4 nanocomposite thin films on SrTiO3(001) substrates were investigated using the Z-contrast imaging and the electron exit-wave reconstruction methods at the atomic scale. The results show that the NiFe2O4 pillars are nonwetting with respect to the substrate and exhibit {111} facets at the surface. The interface between BiFeO3 and NiFe2O4 lies in the {110} planes and is semicoherent. The atomic configuration of the interface, with the BiFeO layer bonding to the [Ni,Fe]O2 layer, was shown to have the maximized structure continuity and minimized interface charging.
Thermoelectric properties of p-type half-Heusler compound HfPtSn and improvement for high-performance by Ir and Co additions
Authors: Kimura Yoshisato , Zama Akihisa
Published: October 2006

The authors found that the half-Heusler compound HfPtSn exhibits p-type thermoelectric behavior, contrary to the HfNiSn counterpart with the same valence electron count of 18 showing n-type behavior. Nearly single crystals of HfPtSn were fabricated using optical floating zone melting method. HfPtSn shows large thermoelectric power while its electrical resistivity and thermal conductivity are relatively high. They improved p-type thermoelectric properties of HfPtSn by the additions of Ir and Co for the Pt site. It aims not only to optimize carrier concentrations but also to suppress an increase in thermal conduction by reducing the lattice contribution through the solid solution effects.
Electrical characterization and Auger depth profiling of nanogap electrodes fabricated by I2-assisted focused ion beam
Authors: Gazzadi G. C. , Angeli E. , Facci P. , Frabboni S.
Published: October 2006

Iodine (I2)-assisted, 30keV Ga+ focused ion beam (FIB) has been employed to fabricate nanogap Au electrodes and has been compared to conventional FIB milling. Electrical characterization shows that I2 assistance improves insulation resistance from 300–400GΩto20–50TΩ. Auger depth profiling reveals that the Ga concentration profile in FIB-milled samples has a peak value of 25at.% at 7nm and extends, with a decreasing Gaussian tail, down to 40nm, whereas in I2-processed samples Ga concentration is reduced below 5at.%. I2 assistance is found to increase minimum gap size from 8to16nm and to markedly roughen Au surface morphology.
Inductance probing into the semiconductor breakdown
Authors: Lee C. I. , Ngo V. H. , Pan D. S.
Published: October 2006

In this letter, an experimental method to unravel mixed interband tunneling and avalanche effects in heavily doped silicon junctions is presented. This method measures the alternating current impedance in the breakdown regime in addition to the direct current characteristics and clearly extracts the avalanche parameters in the presence of strong tunneling. Many phenomena in the high field transport in silicon were observed due to this capability and have important device applications. The method can be applied to other semiconductors as well.
High-efficiency light-emitting column-crystallized InGaN∕GaN quantum-well flower structure on micropillared Si substrate
Authors: Hu F. R. , Ochi K. , Zhao Y. , Hane K.
Published: October 2006

Column-crystallized InGaN∕GaN quantum-well flower structure was deposited on pillared Si (111) substrate. Dotted GaN nuclei grew along the direction of the coming Ga and N atoms, forming arrays of InGaN∕GaN quantum-well flower structure. Raman spectra measurement demonstrated that these crystals were fully relaxed. Photoluminescence measurement showed a room temperature peak position of 556nm and two peak positions of 400 and 549nm at low temperature. Hg lamp excited photoluminescence demonstrated a clear fluorescence distribution from the low to the top part of the flower structure and much stronger emission compared with the quantum-well crystals on the flat Si substrate.
Optical absorption by a semiconductor in the presence of intense radiation fields
Authors: Xu W.
Published: October 2006

Motivated by a recent experiment, the author presents a theoretical study on optical absorption in a semiconductor subjected to pump and probe radiation fields. The electron and hole interactions with midinfrared pump and probe fields are considered and the absorption coefficient is calculated on the basis of a Boltzmann equation approach. It is found that the results obtained theoretically are in line with those observed experimentally and can be used to understand important experimental findings such as the optical absorption in the forbidden zone and the dependence of the absorption of the probe field on intensity and frequency of the pump field.
High performance midinfrared narrow-band plasmonic thermal emitter
Authors: Tsai Ming-Wei , Chuang Tzu-Hung , Meng Chao-Yu , Chang Yi-Tsung , Lee Si-Chen
Published: October 2006

The blackbody radiation spectrum is fundamental to any thermal emitter. However, by properly designing the emitter structure, a narrow bandwidth and high power infrared source can be achieved. This invention consists of a triple layer structure by sandwiching a dielectric SiO2 layer between two Ag metal films on the Si substrate. The top Ag layer is perforated by periodic holes. When the device was heated, the background thermal radiation was suppressed by the bottom Ag whose emissivity is very low. The thermal radiation generated in the SiO2 layer resonant between two metal films and the Ag∕SiO2 and the Ag/air surface plasmon polaritons are induced and converted to light radiation. Strong resonance at Ag∕SiO2 (1,0) degenerate modes results in the coherent light radiation at the wavelength associated with the dielectric constant of SiO2 and the lattice constant of the perforated hole array. The ratio of the full width at half maximum to the peak wavelength is 0.114. This narrow bandwidth and high power infrared light source can be used to explore the biological response of cells and plants.
Alignment layerless flexible liquid crystal display fabricated by an imprinting technique at ambient temperature
Authors: Kim Yeun-Tae , Hwang Seongmo , Hong Jong-Ho , Lee Sin-Doo
Published: October 2006

The authors report on an alignment layerless (AL) flexible liquid crystal (LC) display fabricated at ambient temperature through an imprinting process. One-dimensional microgrooves and two-dimensional arrays of microstructures embossed on plastic substrates provide the spontaneous alignment of the LC molecules and spacers for the uniform cell gap in a flexible LC display, respectively. It is found that the azimuthal anchoring energy, generated from the microgrooves, is on the order of 10−5J∕m2 which is strong enough to uniformly align the LC over large area. Our AL flexible LC display shows symmetric viewing characteristics and stable electro-optic properties under a bent environment.
Doping concentration dependence of ferromagnetic ordering in (Ga,Mn)N nanowires
Authors: Ham Moon-Ho , Myoung Jae-Min
Published: October 2006

The (Ga,Mn)N nanowires with different Mn concentrations of 0.5%–10% were synthesized by varying the separation between MnCl2 and GaN powders under NH3 gas flow via the chemical vapor deposition method. The structural analyses demonstrate that all the nanowires are a single crystal without secondary phases. The room-temperature ferromagnetism was found to depend on Mn concentration in the (Ga,Mn)N nanowires which were converted from n type to p type with increasing Mn concentration. In particular, the highest magnetic moment was shown in the p-type (Ga,Mn)N nanowires with Mn concentration of 5% and hole concentration of 1017cm−3.
Zinc oxide nanorod for intracellular pH sensing
Authors: Al-Hilli S. M. , Al-Mofarji R. T. , Willander M.
Published: October 2006

p H determination is a prerequisite for many biochemical and biological processes. The authors have used two methods, namely, the electrochemical potential method and the site binding method to study the sensitivity of zinc oxide (ZnO) nanorods for the use as intracellular pH sensing device. The dimensions of these nanorods were varied with radii between 50–300nm and lengths between 2 and 10μm. The ZnO nanorods showed a high sensitivity ≈59mV per decade at room temperature for a pH range (1–14), assuming that the solution is water. This is expected due to the polar and nonpolar surfaces of the ZnO nanorods.
Dual-axis micromechanical probe for independent detection of lateral and vertical forces
Authors: Fukuzawa Kenji , Terada Satoshi , Shikida Mitsuhiro , Amakawa Hiroaki , Zhang Hedong , Mitsuya Yasunaga
Published: October 2006

A dual-axis micromechanical probe that combines a double cantilever and torsion beams is presented. This probe can reduce the mechanical cross-talk between the lateral and vertical forces and detect dual-axis forces by measuring the dual-axis displacement of the probe end using the optical lever-based method used in conventional friction force microscopes. By reducing the cross-talk, this new probe design yields improved frictional force measurements for the identification of materials.
Magnetization reversal by spin-transfer torque in 90° configuration with a perpendicular spin polarizer
Authors: Seki T. , Mitani S. , Yakushiji K. , Takanashi K.
Published: October 2006

The effect of spin-transfer torque in 90° magnetization configuration on current-induced magnetization reversal was studied in current-perpendicular-to-plane giant magnetoresistance pillars of in-plane magnetized FePt∕Au∕FePt trilayers combined with an L10-FePt perpendicular spin polarizer. The resistance change associated with the transition of the alignment of the two in-plane magnetizations was observed, showing no significant difference in the magnitude from that of a pillar without the perpendicular spin polarizer. However, the spin-transfer torque from the perpendicular spin polarizer reduced the current density for the magnetization reversal of the in-plane magnetization.
On optical activity of Er3+ ions in Si-rich SiO2 waveguides
Authors: Minissale S. , Gregorkiewicz T. , Forcales M. , Elliman R. G.
Published: October 2006

Photoluminescence spectroscopy was used to explore the optical activity of Er3+ ions in Si-rich SiO2 waveguides prepared by ion implantation. Measurements were performed for a series of materials characterized by different Si excess levels, Er concentrations, and annealing temperatures. The highest fraction of optically active Er3+ ions which can be efficiently activated by nonresonant pumping was found to be 2.6%. This was realized in a waveguide with an Er concentration of [Er]=1018cm−3 and Si excess of 20%, annealed at 900°C. This optical activity level is insufficient to realize optical gain. It is therefore clear that further material improvement is needed before optical amplification in SiO2:Er matrices sensitized by Si nanocrystals/nanoclusters can be achieved.
ZnO hexagonal microboxes enclosed only by {0001} facets with epitaxial nanowalls
Authors: Wang Ruey-Chi , Liu Chuan-Pu , Huang Jow-Lay
Published: October 2006

Hexagonal ZnO microboxes constructed of ZnO {0001} facets with vertical and horizontal single-crystalline nanowalls were synthesized on Si(001) via a self-assembled process by thermal chemical vapor deposition. High-resolution transmission electron microscopy images show that ZnO sheets with nanowalls on top can be assembled at 86° and 62° to each other by twinning and epitaxy, respectively. The room-temperature cathodoluminescence spectrum of the microboxes shows a strong and sharp ultraviolet emission as well as a negligible green emission. The vertical and horizontal nanowalls have potential to be applied as templates for growth of vertically and horizontally aligned nanowires for three-dimensional nanoelectronics.
Pressure response of the ultraviolet photoluminescence of ZnO and MgZnO nanocrystallites
Authors: Huso Jesse , Morrison John L. , Hoeck Heather , Chen Xiang-Bai , Bergman Leah , Jokela S. J. , McCluskey M. D. , Zheleva Tsvetanka
Published: October 2006

The pressure response of the ultraviolet photoluminescence of ZnO nanocrystallites and MgZnO nanoalloy of composition 15% Mg:85% Zn of the wurtzite structure was studied. The authors found that up to 7GPa the pressure coefficients of ZnO and MgZnO are 23.6 and 27.1meV∕GPa, respectively. The pressure coefficient of the ZnO nanocrystallites is similar to that reported elsewhere for bulk ZnO material. The higher value found for MgZnO is discussed in terms of the d orbitals of the alloy constituents and their compliance to stress. Additionally, the volume deformation potential was derived from the experimental results.
Semiconductor-metal transition in InSb nanowires and nanofilms under external electric field
Authors: Zhang X. W. , Li S. S. , Xia J. B.
Published: October 2006

The electronic structures, Rashba spin-orbit couplings, and transport properties of InSb nanowires and nanofilms are investigated theoretically. When both the radius of the wire (or the thickness of the film) and the electric field are large, the electron bands and hole bands overlap, and the Fermi level crosses with some bands, which means that the semiconductors transit into metals. Meanwhile, the Rashba coefficients behave in an abnormal way. The conductivities increase dramatically when the electric field is larger than a critical value. This semiconductor-metal transition is observable at the room temperature.
Roles of
Arabidopsis
ATP/ADP isopentenyltransferases and tRNA isopentenyltransferases in cytokinin biosynthesis
Authors: Miyawaki Kaori , Tarkowski Petr , Matsumoto-Kitano Miho , Kato Tomohiko , Sato Shusei , Tarkowska Danuse , Tabata Satoshi , Sandberg Göran , Kakimoto Tatsuo
Published: October 2006

Cytokinins, which are central regulators of cell division and differentiation in plants, are adenine derivatives carrying an isopentenyl side chain that may be hydroxylated. Plants have two classes of isopentenyltransferases (IPTs) acting on the adenine moiety: ATP/ADP isopentenyltransferases (in
Arabidopsis thaliana, AtIPT1, 3, 4–8
) and tRNA IPTs (in
Arabidopsis, AtIPT2 and 9
). ATP/ADP IPTs are likely to be responsible for the bulk of cytokinin synthesis, whereas it is thought that
cis
-zeatin (
c
Z)-type cytokinins are produced possibly by degradation of
cis
-hydroxy isopentenyl tRNAs, which are formed by tRNA IPTs. However, these routes are largely hypothetical because of lack of
in vivo
evidence, because the critical experiment necessary to verify these routes, namely the production and analysis of mutants lacking
AtIPT
s, has not yet been described. We isolated null mutants for all members of the ATP/ADP IPT and tRNA IPT gene families in
Arabidopsis
. Notably, our work demonstrates that the
atipt1 3 5 7
quadruple mutant possesses severely decreased levels of isopentenyladenine and
trans
-zeatin (
t
Z), and their corresponding ribosides, ribotides, and glucosides, and is retarded in its growth. In contrast, these mutants possessed increased levels of
c
Z-type cytokinins. The
atipt2 9
double mutant, on the other hand, lacked isopentenyl- and
cis
-hydroxy isopentenyl-tRNA, and
c
Z-type cytokinins. These results indicate that whereas ATP/ADP IPTs are responsible for the bulk of isopentenyladenine- and
t
Z-type cytokinin synthesis, tRNA IPTs are required for
c
Z-type cytokinin production. This work clarifies the long-standing questions of the biosynthetic routes for isopentenyladenine-,
t
Z-, and
c
Z-type cytokinin production.
A peptide zipcode sufficient for anterograde transport within amyloid precursor protein
Authors: Satpute-Krishnan Prasanna , DeGiorgis Joseph A. , Conley Michael P. , Jang Marcus , Bearer Elaine L.
Published: October 2006

Fast anterograde transport of membrane-bound organelles delivers molecules synthesized in the neuronal cell body outward to distant synapses. Identification of the molecular “zipcodes” on organelles that mediate attachment and activation of microtubule-based motors for this directed transport is a major area of inquiry. Here we identify a short peptide sequence (15 aa) from the cytoplasmic C terminus of amyloid precursor protein (APP-C) sufficient to mediate the anterograde transport of peptide-conjugated beads in the squid giant axon. APP-C beads travel at fast axonal transport rates (0.53 μm/s average velocity, 0.9 μm/s maximal velocity) whereas beads coupled to other peptides coinjected into the same axon remain stationary at the injection site. This transport appears physiologic, because it mimics behavior of endogenous squid organelles and of beads conjugated to C99, a polypeptide containing the full-length cytoplasmic domain of amyloid precursor protein (APP). Beads conjugated to APP lacking the APP-C domain are not transported. Coinjection of APP-C peptide reduces C99 bead motility by 75% and abolishes APP-C bead motility, suggesting that the soluble peptide competes with protein-conjugated beads for axoplasmic motor(s). The APP-C domain is conserved (13/15 aa) from squid to human, and peptides from either squid or human APP behave similarly. Thus, we have identified a conserved peptide zipcode sufficient to direct anterograde transport of exogenous cargo and suggest that one of APP's roles may be to recruit and activate axonal machinery for endogenous cargo transport.
Thrombocytopenia and kidney disease in mice with a mutation in the
C1galt1
gene
Authors: Alexander Warren S. , Viney Elizabeth M. , Zhang Jian-Guo , Metcalf Donald , Kauppi Maria , Hyland Craig D. , Carpinelli Marina R. , Stevenson William , Croker Ben A. , Hilton Adrienne A. , Ellis Sarah , Selan Carly , Nandurkar Harshal H. , Goodnow Christopher C. , Kile Benjamin T. , Nicola Nicos A. , Roberts Andrew W. , Hilton Douglas J.
Published: October 2006

An
N
-ethyl-
N
-nitrosourea mutagenesis screen in mice was performed to isolate regulators of circulating platelet number. We report here recessive thrombocytopenia and kidney disease in
plt1
mice, which is the result of a severe but partial loss-of-function mutation in the gene encoding glycoprotein-
N
-acetylgalactosamine-3-β-galactosyltransferase (C1GalT1), an enzyme essential for the synthesis of extended mucin-type O-glycans. Platelet half-life and basic hemostatic parameters were unaffected in
plt1/plt1
mice, and the thrombocytopenia and kidney disease were not attenuated on a lymphocyte-deficient
rag1
-null background. gpIbα and podocalyxin were found to be major underglycosylated proteins in
plt1/plt1
platelets and the kidney, respectively, implying that these are key targets for C1GalT1, appropriate glycosylation of which is essential for platelet production and kidney function. Compromised C1GalT1 activity has been associated with immune-mediated diseases in humans, most notably Tn syndrome and IgA nephropathy. The disease in
plt1/plt1
mice suggests that, in addition to immune-mediated effects, intrinsic C1Gal-T1 deficiency in megakaryocytes and the kidney may contribute to pathology.
Complete correction of murine Artemis immunodeficiency by lentiviral vector-mediated gene transfer
Authors: Mostoslavsky Gustavo , Fabian Attila J. , Rooney Sean , Alt Frederick W. , Mulligan Richard C.
Published: October 2006

Artemis gene mutations are responsible for the development of a severe combined immunodeficiency [radiation-sensitive (RS) SCID] characterized by a severe B and T cell deficiency and a normal natural killer cell population. To establish the feasibility of a gene therapy approach to the treatment of RS-SCID, we generated a series of lentiviral vectors expressing human Artemis from different promoters and used them to transduce highly purified hematopoietic stem cells (HSCs) from Artemis knockout mice. HSCs transduced by the different viruses were transplanted into either lethally irradiated Rag-1-deficient animals or Artemis knockout mice treated with a nonmyeloablative dose of Busulfan. In both models, transplantation of HSCs transduced by a vector that used a murine phosphoglycerate kinase (PGK) promoter led to a complete functional correction of the immunodeficiency. Corrected animals displayed rescue of mature B cells with normal levels of serum immunoglobulins, together with complete rescue of the T cell compartment as evidenced by the presence of mature T lymphocytes in peripheral blood as well as normal values of thymocytes in thymus. Those B and T cells were capable of activation, as shown both by
in vitro
stimulation responses and
in vivo
after immune challenge. Overall, the results indicate that a gene therapy approach for RS-SCID involving the transplantation of genetically modified HSCs is indeed feasible. Furthermore, our studies suggest the possibility that nonmyeloablative conditioning regimens might be effectively used to promote engraftment of genetically modified cells in the case of diseases where standard irradiation-based myeloablative bone marrow transplantation protocols may prove problematic.
An Econometric Model of Migration Between US Metropolitan Areas
Authors: Alperovich Gershon , Bergsman Joel , Ehemann Christian
Published: October 2006

We test a model of inter-metropolitan migration using 1965-70 data for 284 metropolitan areas from the 1970 Census of Population. Innovations in model specification permit us to derive estimatable equations for gross in- and out-migration from a point-to-point hypothesis. Measures of economic conditions (the unemployment rate, the growth rate in employment, and the wage rate) are shown to affect migration behaviour both at origins and destinations, as economic theory predicts. Expected effects of past migration on both subsequent in-migration and out-migration are confirmed. In addition, migrants are shown to prefer destination cities that have moderate climates, that are relatively small in size, and that are close to larger cities.

The research reported in this paper is part of a larger study of the joint determination of growth in employment in US metropolitan areas and of migration flows between them.
Reconciliation Techniques in Input-Output Analysis: Some Comparisons and Implications
Authors: Jensen R.C. , McGaurr D.
Published: October 2006

The paper describes a number of reconciliation techniques adopted in the construction of regional input-output tables and compares the multiplier and output projections from reconciled and unreconciled tables. The unreconciled tables considered are the rows only and columns only tables: the reconciled tables are those based upon arithmetic means, geometric means, two types of weighted averages and the Friedlander and RAS techniques. By comparing estimates of multipliers and outputs derived from these procedures with 'real' values based upon data for central Queensland and Toowoomba, the authors are able to demonstrate the range of results derived from the eight methods and the overall suitability of the weighted RAS method for most purposes.
Income and Residential Location: Muth Revisited
Authors: Diamond Douglas B.
Published: October 2006

In Cities and Housing, Muth modeled residential location by income in terms of the conflicting desires for a low price of housing and access to CBD. This paper expands Muth's model to include in the location decision locational amenities other than access. Land values around Chicago are then used to estimate the income elasticities of the bids for access and five other amenities. The results indicate that the value of access may rise more rapidly with income than Muth expected and that, in the absence of other amenities and a durable housing stock, higher income residents would live closer to the CBD than low-income residents. Furthermore, other amenities may be important determinants of residential location patterns.
A Re-examination of the Incubator Hypothesis: A Case Study of Greater Leicester
Authors: Fagg J.J.
Published: October 2006

Although the inner city has traditionally been regarded as a 'nursery' for the birth and growth of new manufacturing firms, recent research has tended to refute this 'incubator' hypothesis. In this paper it is argued that such research has been based on an unsatisfactory methodology. An alternative approach is adopted in a case study of the location of new industrial companies in Greater Leicester between 1957 and 1970. The results provide considerable support for the incubator hypothesis, while indicating that pockets of nineteenth-century development within the present urban periphery also perform a nursery function.
Stability of Trade Patterns in Regional Input-Output Tables
Authors: Baster Jeremy
Published: October 2006

Applications of input-output tables generally involve an assumption of the stability over time of trade patterns, although evidence supporting this is thin, especially at the regional level. Data from Strathclyde at the level of the individual establishment over the 2-year period 1974-76 indicates a high level of stability, especially when aggregated at the industry level. It also gives some support to the hypothesis that instability is concentrated in products with a high value-to-weight ratio.
Industrial Environments: a Niche Theoretic Interpretation
Authors: Keys Paul , Thrift Nigel
Published: October 2006

The problem of exact quantitative definition of the concept of an industrial environment is examined. One possible approach that might be adopted is the idea of the niche and, in particular, the niche pattern. Experiments which use synthesised data sets to summarise the urban industrial environment of Britain are outlined. Two data sets are constructed - one using 1971 cross-sectional information and one limited time-series information. From these data sets it is possible to derive an overall niche pattern for eight different kinds of firm for both the cross-sectional and time-series cases. The interpretation of these patterns seems to indicate the utility of a niche-theoretic approach as a heuristic device and, perhaps, with larger and more refined data sets, as an analytical device.
Intra-Urban Unemployment Differentials in Sydney, 1971
Authors: Vipond Joan
Published: October 2006

This paper analyses intra-urban unemployment differentials among male and female workers in Sydney in 1971. Neo-classical models of the labour market and urban development provide the theoretical background. Comparisons are made with UK studies which suggest that high unemployment in inner city areas can be explained either by the fact that more 'unemployables' live in such areas (a supply oriented explanation) or by the suburbanisation of jobs (a demand-oriented explanation). In Sydney there was a clearly defined spatial pattern in unemployment rates that was the same as that found in UK studies - the nearer a location to the core of Sydney, the higher was the unemployment rate among male residents. However, no spatial pattern could be detected in female unemployment rates. Supply and demand explanations are suggested for this absence of high inner city unemployment among women. It is concluded that policies designed to cure male unemployment in inner areas could have harmful effects on women's employment opportunities.
Planning Theory and the Philosophy of Planning
Authors: Taylor Nigel
Published: October 2006

Planning theories have commonly embodied a mixture of sociological assumptions about human and social behaviour and philosophical assumptions about the nature, purposes and premises of planning. Both the sociological and philosophical assumptions of planning warrant thorough examination. This article argues the case for the systematic examination of the philosophy of planning by examining two areas where philosophical analysis might help to elucidate, and critically examine, philosophical assumptions made in planning thought and practice. These are the areas of ethics and epistemology. Prior to this examination, philosophy is itself defined, and the relationship between ethical and epistemological judgments is discussed with respect to the logical distinction that can be made between facts and values.
The Inner City Employment Problem in Great Britain, 1952-76: a Shift-Share Approach
Authors: Danson M.W. , Lever W.F. , Malcolm J.F.
Published: October 2006

Employment data for 1952, 1963, 1968, 1973 and 1976 for the British conurbations are analysed to demonstrate the extent of job loss in the inner city areas and the growth of the outer city areas. Shift-share analysis is used at a 116-sector level of disaggregation to identify the structural and residual components of this employment change. It is clear that the inner cities consistently have a positive structural component so that their poor employment performance cannot be attributed to sectoral mix. The outer areas generally had a less favourable structure so that their positive residual components reflect a 'better than average performance'. This disparity between inner and outer city areas cannot be explained by short distance relocation. Most industries appear to be affected by the inner city problems as measured by the residual component.
Mixed-Use Area Development Control
Authors: Tucker S.N.
Published: October 2006

The significance of the ratio of the floor area to site area in determining the economics of competing land uses in city mixed-use areas has been investigated. Theoretical analysis leads to a simple rule which defines the conditions for equal opportunity for alternative types of development in a mixed-use area. This rule is that the floor area to site area ratio limit applied to each land use should be inversely proportional to the capitalised building cost per unit gross floor area of building. The validity of the rule is demonstrated by detailed economic assessments of building developments typical of home units, town houses, flat and small office developments in areas designated mixed use in the City of Melbourne.
Spatial Choice and Interaction Models: Criteria and Aggregation
Authors: van Lierop Wal , Nijkamp Peter
Published: October 2006

The paper provides a framework for judging various spatial choice and interaction models on the basis of methodological, theoretical, logical and practical criteria. After a brief discussion of several common models (such as gravity models, entropy models, logit models, probit models and multiproportional Poisson models), the significance of these models is assessed by confronting them with the above-mentioned criteria, so that a qualitative evaluation can be made.

The logit model which turns out to be a rather satisfactory spatial interaction model, is dealt with in more detail. Especially the problems of aggregation and disaggregation are analysed, while also a new contribution to logit models is provided by constructing a general probability density function for the population in case of more than two choice alternatives.
Asians and Council Housing
Authors: Robinson Vaughan
Published: October 2006

Current theories explaining Asian non-participation in council housing are described and criticised. An analysis of the situation in the northern industrial city of Blackburn, Lancashire, serves to highlight the increasing inadequacies of these theories. Evidence presented here suggests that, for a number of reasons, Asians are now applying for, and being granted, council houses in significantly larger numbers. The reasons for this are discussed in detail, as are temporal and spatial patterns of residence. Patterns of intra-urban mobility occasioned by the move into council housing are also discussed as is the likely impact of such mobility on overall levels of segregation.
An Empirical Analysis of the Determination of House Prices in the United Kingdom
Authors: Nellis Joseph G. , Longbottom J. Andrew
Published: October 2006

Between the first quarters of 1970 and 1980 the average price of new houses in the United Kingdom increased five-fold. Over the same period building societies grew to become major financial institutions, attracting almost 50 per cent of the personal sector's holdings of liquid assets, and responsible for more than 85 per cent of house purchase finance. This paper sets out to examine the extent to which building societies have been responsible for the rapid acceleration of house prices and indicates the other main determinants of this phenomenon. The analysis is extended to a discussion of recent econometric research into house price determination and arrives at a more general specification, employing an error-correction estimation methodology.
Equilibrium of a Residential City, Attributes of Housing, and Land-Use Zoning
Authors: Büttler Hans-Jürg
Published: October 2006

This paper investigates the impact of land-use zoning such as building-height and building-density restrictions on housing rent, land rent, the design parameters of a building, and population density in a residential city. A theoretical land-use model with several new features is used. Building capital, the demand for, and the supply of housing are explicitly defined. Housing is treated as a multi-dimensional good, the elements of which are floor area, finishing cost of a dwelling unit, garden space, and building height. Building costs are the sum of structural frame costs, which are a function of building height and building area, and finishing costs, which are independent of design parameters. Zoning restrictions are explicitly considered. The utility and profit maximisations are simultaneous through the housing attributes, which are implicitly priced. There are six major conclusions: First, the relative gradients of the endogeneous variables, all with regard to distance, depend not only on demand specifications but also on structural frame cost elasticities, i.e. supply specifications. Secondly, in empirical tests the free market and zoning restrictions can be discriminated with regard to housing rent if, and only if, housing attributes are taken into account. Thirdly, both the relative housing-rent gradient and land-rent gradient are the same with zoning restrictions. Fourthly, the finishing cost of a dwelling unit depends on the household's taste and income and is the same in all cases. Fifthly, while in the case of the free market a residential city with one income class could consist of single-family homes only, this is impossible in the case of binding zoning restrictions. Sixthly, the cost of zoning restrictions to tenants, or the loss of utility in terms of money, can be obtained from the indirect utility function evaluated at the equilibrium.
Neighbourhood Change in Inner Adelaide, 1966-76
Authors: Badcock B.A. , Cloher D.U. Urlich
Published: October 2006

The inner residential areas of Australian cities have not experienced the neighbourhood decline associated with the restructuring of old British and US industrial cities. Rather, neighbourhood change near the centre of Australian cities during the 1960s and 70s has been characterised by reinvestment in land and structures. Residential rejuvenation in one such city is illustrated with a case study of Inner Adelaide between 1966 and 1976. This involves documenting the regional shift, 1966-76, in the occupational structure of the workforce residing in Inner Adelaide. Next we outline the main features of a typology which is then used to reveal the direction, nature and spatial expression of neighbourhood transition within Inner Adelaide, 1966-76. Lastly, some reasons are advanced for the predominantly upward trajectory of neighbourhood change in the inner areas of large Australian cities.
The Role of the Inner City in the Development of Manufacturing Industry
Authors: Nicholson B.M. , Brinkley Ian , Evans Alan W.
Published: October 2006

The first section of the paper surveys the evidence relating to the hypothesis that the inner city acts as a nursery for new manufacturing firms and shows that there is little direct confirmatory evidence. The second and third sections report on two research studies of new firm foundation in London. In the first study it is shown that few manufacturing firms have been set up in inner London in recent years, the majority being in the 'inner city industries' of printing, clothing, etc. In the second the founders of new manufacturing firms, not in the inner city industries, were located and interviewed to find out the reasons for their choice of location. The two studies together tend to refute the inner city nursery hypothesis.
A Neo-Classical Supply-Based Approach to Land Prices
Authors: Needham Barrie
Published: October 2006

Current interest in land-price theory is dominated by attempts to explain the structure of land prices and land uses in urban areas. Those theories, however, do not enable certain important political issues to be elucidated, in particular the relationship between produce price and land price. A different approach is therefore suggested, which considers the supply of land to consist of a supply of stocks of land differentiated by fertility, location, etc., the production function for an industry being different for each type of land used. By using the conventional tools of neo-classical analysis, the relationships between land price, product price, and the intensity of land use are derived, also the effect on land and product prices of competition for land between different industries.
Industrial Employment Performance and Regional Policy 1952-71: a Cross-Sectional Approach
Authors: Thomson Lydia
Published: October 2006

The paper describes a cross-sectional regression analysis for fourteen manufacturing orders of the factors explaining industrial mobility, the share of movement going to the development areas, and overall employment performance in the development areas relative to the nation (measured as the differential shift). Explanatory variables included national growth, plant size, labour force composition, and capital intensity. Two main time periods were studied: 1952-60 when regional policy was weak and 1960-71 when policy was strong. Sub-period results for 1960-71 were used to examine the effects of the changes in regional policy instruments, particularly the regional employment premium.
A Hierarchical Model of Housing Choice
Authors: Boehm Thomas P.
Published: October 2006

The main objective of this paper is the construction of an expanded model of housing choice that includes not only tenure choice, which has traditionally been the subject of analysis, but also other housing characteristic choices. In this model the probability of the household making a given tenure choice is estimated at the first level of a choice hierarchy. The family's choices over dwelling size and quality are then estimated at succeeding levels of that hierarchy, conditionally on the choices which precede them. These conditional probabilities can be combined with the probability of tenure choice to produce eight joint probabilities of housing choice. In addition, for a particular household or group of households, we can determine the effect of a change in any of the systems variables on the probability of the families making a given housing choice.

In the empirical section it is demonstrated that this model provides much greater insight than the conventional tenure choice study regarding the effects of income, relative prices, and other socioeconomic variables on the family's housing choices. Consequently, it is concluded that models of this type should provide a superior tool for designing effective housing policy.
Residential Mobility in a Changing Housing Market: the Case of Bucaramanga, Colombia
Authors: Edwards Michael
Published: October 2006

Using empirical evidence from Bucaramanga, Colombia, this paper sets out to demonstrate that patterns of residential mobility among low-income groups are intimately related to the changing structure of the local housing market. Specifically, the paper examines the links which exist between intra-urban migration, housing moves, and the family life cycle, during successive periods in the growth of the city. As the housing market develops, the relationships between the different dimensions of residential mobility are seen to vary quite considerably. This is in sharp contrast to Turner's seminal work on residential mobility among the urban poor in Latin American cities.
A Model for the Interaction of Migration and Commuting
Authors: Congdon Peter
Published: October 2006

This paper presents a simultaneous equations model for the interaction of migration with changes in commuting, employment and housing stocks, and applies the model to census data for Greater London. Different spatial frames of reference are used: intra-metropolitan, intra-regional, and national. The results suggest an interdependence of migration and commuting with the decentralisation of employment within Greater London. Migration is influenced by tenure structure and turnover in the existing housing stock as well as by the availability of new housing.
The Retired Migrant: A Study in North Wales
Authors: Davies Richard B. , Davies Sheila
Published: October 2006

This study seeks to identify the distinctive social, economic and demographic characteristics of retired migrants in a study area on the North Wales Coast and thus contributes to the surprisingly limited research literature on retirement migration in Britain. A hypothesis testing framework is adopted and an important feature of the study is the extensive use of control by disaggregation to disentangle the compounding effects of different characteristics. Although the study confirms that the retired migrant is typically an owner occupier of a bungalow and comparatively isolated geographically from his children, the results generally provide little unequivocal support for previous research findings.
Municipal Boundaries in a Discriminatory Housing Market: An Example of Racial Leapfrogging
Authors: Rich Jonathan M.
Published: October 2006

Racial 'leapfrogging' occurs when some blacks settle farther from the urban core and inner city ghettos than some whites. Previously, this phenomenon has only been discussed as a theoretical possibility by Courant and Rose-Ackerman. This article gives evidence of leapfrogging across a municipal boundary under circumstances somewhat similar to those of the Rose-Ackerman model. However, the cause of the leapfrogging is less organized than that posited by Rose-Ackerman. Blacks jumped over more affluent whites in the inner city to a nearby suburb because they were discouraged by racial prejudice from locating in white neighborhoods in the central city and because the neighboring community has better schools and less crime.
The Fiscal Condition of American and Canadian Cities
Authors: Mercer John , Goldberg Michael A.
Published: October 2006

The fiscal condition of American and Canadian cities is examined in this paper using municipal bond ratings from Moody's Investors Service for the period 1970-1980. Two hypotheses are posited: that Canadian central cities will exhibit greater fiscal health than will American central cities; over time Canadian and US cities will exhibit differences in changes in bond ratings with changes being more positive for the Canadian case.

Neither hypothesis is refuted by the bond rating evidence presented in the paper. While the limited size of the Canadian sample of cities with Moody's bond rating precludes rigorous statistical tests, the findings are consistent with previous work which suggests that there are significant differences between Canadian and US cities and that the North American City concept must be used with care.
The Pricing of Land Options
Authors: Brown Robert L. , Achour Dominique
Published: October 2006

Valuation principles which have been found useful in the study of stock options are applied to the pricing of options to purchase real property ('land options'). There is a close similarity between fixed land options and call options on common stock. This similarity is used to saggest ways in which fixed land options might be valued. More complex land options (step-up, full credit and renewable) are also analyzed.
Functional Form and Rental Housing Market Analysis
Authors: Goodman Allen C. , Kawai Masahiro
Published: October 2006

This paper tests functional form for hedonic rent regressions and for rental housing demand regressions for 19 United States metropolitan areas. In the hedonic rent regressions, both linear and loglinear forms are rejected through Box-Cox maximum likelihood procedures. Similar tests for demand regressions also reject both linear and loglinear forms. These results have useful applications to the analysis of rental housing demand by low income households. The more popular logarithmic and linear forms lead to very low estimated income elasticities for households in the low income range, whereas the preferred form provides elasticities that are significantly higher. This implies greater responsiveness to income subsidies than might otherwise be estimated.
Approaches to Information Management in County Planning Authorities in England and Wales
Authors: Masser Ian , Wilson Tom
Published: October 2006

The paper describes the findings of a survey of information management in the 54 country planning authorities of England and Wales. They indicate the extent to which current county planning practice is directed towards economic regeneration and the degree to which monitoring activities are still regarded as evolving despite the long time interval that has elapsed in many cases since the initial submission of the County structure plans. They show that there is a strong relationship between attitudes towards data collection, information handling and data dissemination. Authorities that favour 'hard' information handling strategies tend also to adopt a restricted approach to data collection, employing regular reporting procedures, and regard lack of relevant information as the most serious operational problem, whereas authorities that favour 'soft' documentary information handling strategies tend to favour comprehensive information gathering strategies, use ad hoc reporting procedures and regard information retrieval and lack of communication channels as the most serious operational problem.
Urban Housing Satisfaction in a Transitional Society: A Case Study in Taichung, Taiwan
Authors: Yi Chin-chun
Published: October 2006

This paper examines factors related to two dimensions of housing satisfaction: satisfaction with space, and satisfaction with location. Two research issues are also examined: the first compares the pattern of housing satisfaction in Taichung with the Western pattern; the second focuses on whether migrant status has any significant effect. The results show that better interior quality is the most important factor accounting for satisfaction with space and that locational satisfaction is inversely related to distance from the city centre. The effects of migrant status and educational level suggest that the profile of housing satisfaction does not closely follow the Western pattern.
The Supply of Land
Authors: Wiltshaw D.G.
Published: October 2006

The supply of land to a use may result from individual suppliers maximizing utility. As a consequence: the slope of the supply curve cannot be determined a priori; supply will be influenced by the distribution of non-land income; different tenure categories will behave according to the balance of substitution and welfare effects; compulsory purchase may be necessary to surmount individual preferences; and the effect of a development gains tax on change of use will depend upon the relation between the rate of tax, the tax base, and the supplier's compensating variation.