145 research outputs found

    A Stepwise Efficiency Improvement DEA Model for Airport Operations with Fixed Production Factors

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    In the spirit of the deregulation movement, Japan is also faced with an ÃgAsia Open SkyÃh agreement which favours aviation liberalization in international services. This means an end to Japan's aviation policy of isolation. In association with this policy change, also environmental concerns grew increasingly severe for small and local regional airports. Consequently, there is a need for an objective analysis of the efficiency of airport operations in Japan. A standard tool to judge the efficiency of such activities is Data Envelopment Analysis (DEA). In the past years, much progress has been made to extend this approach in various directions. Interesting examples are the Distance Friction Minimization (DFM) model and the Context-Dependent (CD) model. The DFM model is based on a generalized distance friction function and serves to improve the performance of a Decision Making Unit (DMU) by identifying the most appropriate movement towards the efficiency frontier surface. Standard DEA models use a uniform input reduction in the improvement projections, but the DFM approach aims to enhance efficiency strategies by introducing a weighted projection function. This approach may address both input reduction and output increase as a strategy of a DMU. Likewise, the CD model yields efficient frontiers at different levels, while it is based on a level-by-level improvement projection. The Stepwise DFM model is an integration of the DFM and the CD model in order to design a stepwise efficiency-improving projection model for a conventional DEA. In general, a DEA model – and neither the mix of the DFM-CD model – doesnÃft take into account a fixed factor. Such a non-controllable of fixed factor may refer to a production factor that cannot be flexibly adjusted in the short run. In our study the newly integrated Stepwise DFM-CD model will be extended with a fixed factor model in order to adapt the DEA model to realistic circumstances in an efficiency improvement projection. The above-mentioned stepwise fixed factor projection model is illustrated on the basis of an application to the efficiency analysis of airport operations in Japan in light of the above mentioned contextual changes in aviation policy.

    Quantum Phase transition under pressure in a heavily hydrogen-doped iron-based superconductor LaFeAsO

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    Hydrogen (H)-doped LaFeAsO is a prototypical iron-based superconductor. However, its phase diagram extends beyond the standard framework, where a superconducting (SC) phase follows an antiferromagnetic (AF) phase upon carrier doping; instead, the SC phase is sandwiched between two AF phases appearing in lightly and heavily H-doped regimes. We performed nuclear magnetic resonance (NMR) measurements under pressure, focusing on the second AF phase in the heavily H-doped regime. The second AF phase is strongly suppressed when a pressure of 3.0 GPa is applied, and apparently shifts to a highly H-doped regime, thereby a "bare" quantum critical point (QCP) emerges. A quantum critical regime emerges in a paramagnetic state near the QCP, however, the influence of the AF critical fluctuations to the SC phase is limited in the narrow doping regime near the QCP. The optimal SC condition (TcT_c \sim 48 K) is unaffected by AF fluctuations

    Effective Clusters as Territorial Performance Engines in a Regional Development Strategy - A Triple-Layer DEA Assessment of the Aviation Valley in Poland

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    Regional development policy aims to cope with the challenge of spatial disparities. It is based on a smart combination of various critical capital assets in a region which functionally and spatially interact and which yield synergetic economic opportunities and promising challenges for innovation and progress. The present study regards sustainable territorial performance – as a manifestation of regional development – as the overarching principle for competitive advantages and economic growth in a system of regions, which is particularly induced by territorial capital, comprising human capital, infrastructural capital and social capital. In the long-standing tradition of regional development policy a wide variety of effective facilitators or drivers of accelerated spatial growth has been distinguished, for instance, industrial districts, growth poles, growth centers, industrial complexes, special economic zones, communication axes, and so forth. In the past decades, a new concept has been introduced, viz. economic-technological clusters. An avalanche of literature has been published on the conceptual, operational and policy foundation and relevance of this concept, especially in relation to previously developed regional growth concepts. In this paper, clusters will be regarded as the spatial foci of sustainable territorial performance strategies and synergetic actions by both public and private actors. The present paper aims to address the relevance of cluster concepts for an effective regional development policy, based on the above notion of territorial capital. It does so by introducing a new concept, viz. effective cluster, in which spatial-economic synergy, local/regional concentration of industry, and the supporting role of territorial capital are regarded as the main determinants of a highly performing cluster in a given territory. The effective cluster concept will be tested on the basis of a field study on the aviation and aerospace cluster ‘Dolina Lotnicza’ in the Podkarpackie region in South-East Poland. This is one of the most vibrant high-tech clusters in the country. A new approach based on a triple-layer architecture will be adopted here, viz.: a quantitative comparative analysis of the 16 Polish ‘voivodships’ (main administrative regions in the country, at a NUTS-2 level), a benchmark analysis of the 25 counties (‘powiats’) within the Podkarpackie voivodship (at a NUTS-4 level), and an effective industrial cluster analysis on the basis of the individual aviation firms located in the Podkarpackie region. In each step an extended Data Envelopment Analysis (DEA), characterised by a merger of a Slack-Based Measure (SMB) and a super-efficiency (SE) DEA, will be used in order to achieve an unambiguous ranking of the various regions or Decision Making Units (DMUs). The study will employ an extensive database on individual actors in the cluster, in combination with a broadly composed territorial-capital database for the areas under study. The paper will be concluded with some strategic policy lessons

    A Study on Evaluation of Healing Level Using Brainwave Stimulated by Tourist Spot Image

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    Healing is an emotion that even the person himself is hard to notice. In this paper, healing levels of tourist spots are evaluated using brainwaves stimulated by tourist spot images. Healing level is estimated by a ratio of the sum of spectral elements in α waveband to that in β waveband. From an experiment using eight subjects, it is found that tourist spots in white- and gray-colored images are evaluated as being healed since the visual perception of human beings is greatly influenced by color

    Delayed healing at free ALT donor site

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    Background The free anterolateral thigh (ALT) flap has been widely used for various kinds of reconstructions. However, delayed healing at the donor site occasionally occurs due to wound dehiscence or the partial loss of grafted skin at the donor site. The aim of the present study was to identify reliable predictive factors for delayed healing at the donor site after the harvest of a free ALT flap. Methods This study included 52 patients who underwent reconstructive procedures using free ALT flaps. The delayed healing group included patients with wounds at the donor site that had not healed over 3 weeks after surgery, and the normal healing group included patients who showed wound healing within 3 weeks after surgery. Multivariate logistic regression models were created to identify the risk factors for delayed healing at the ALT flap donor site. Results Among the 52 patients, 24 (46.2%) showed delayed healing at the donor site, and 6 patients required additional operative treatment. A high preoperative body mass index (BMI), smoking, and skin grafting were found to be significantly associated with delayed healing at the ALT donor site. Of the 37 patients who underwent skin grafting, 23 (62%) experienced delayed healing at the donor site. Conclusions A high preoperative BMI, smoking, and skin grafting were risk factors for delayed healing at the free ALT donor site. Skin grafting at the ALT donor site should be avoided in patients with a high BMI or a habit of smoking

    Automated classification of heat sources detected using SWIR remote sensing

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    Abstract The potential of shortwave infrared (SWIR) remote sensing to detect hotspots has been investigated using satellite data for decades. The hotspots detected by satellite SWIR sensors include very high-temperature heat sources such as wildfires, volcanoes, industrial activity, or open burning. This study proposes an automated classification method of heat source detected utilizing Landsat 8 and Sentinel-2 data. We created training data of heat sources via visual inspection of hotspots detected by Landsat 8. A scheme to classify heat sources for daytime data was developed by combining classification methods based on a Convolutional Neural Network (CNN) algorithm utilizing spatial features and a decision tree algorithm based on thematic land-cover information and our time series detection record. Validation work using 10,959 classification results corresponding to hotspots acquired from May 2017 to July 2019 indicated that the two classification results were in 79.7% agreement. For hotspots where the two classification schemes agreed, the classification was 97.9% accurate. Even when the results of the two classification schemes conflicted, either was correct in 73% of the samples. To improve the accuracy, the heat source category was re-allocated to the most probable category corresponding to the combination of the results from the two methods. Integrating the two approaches achieved an overall accuracy of 92.8%. In contrast, the overall accuracy for heat source classification during nighttime reached 79.3% because only the decision tree-based classification was applicable to limited available data. Comparison with the Visible Infrared Imaging Radiometer Suite (VIIRS) fire product revealed that, despite the limited data acquisition frequency of Landsat 8, regional tendencies in hotspot occurrence were qualitatively appropriate for an annual period on a global scale

    Granulomatous interstitial nephritis associated with atypical drug-induced hypersensitivity syndrome induced by carbamazepine

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    We report the case of a 70-year-old female patient with granulomatous interstitial nephritis (GIN) induced by carbamazepine (CBZ). The patient had a 22-year history of bipolar disorder. Approximately 50 days before admission to our hospital, she was switched from valproic acid to 200 mg/day CBZ for mood swings. Forty days later, she presented with mild transient platelet depletion and liver dysfunction along with a C-reactive protein (CRP) level of 2.65 mg/dL. At that time, she discontinued CBZ without consulting the doctor. She subsequently developed high fever and a pruritic maculopapular rash. Laboratory tests revealed an elevated CRP level (11.98 mg/dL) and serum creatinine (sCr) of 1.6 mg/dL. Hence, she was admitted to our hospital, where she showed eosinophilia and immunoglobulin suppression. She was diagnosed with atypical drug-induced hypersensitivity syndrome (DIHS). All drugs prescribed by the previous doctor were discontinued. A lymphocyte transformation test showed CBZ positivity; a renal biopsy revealed many granulomatous lesions connected to arterioles, without angionecrotic findings. The patient had no history of allergic disorders or tuberculosis. Because of psychological instability, we treated her conservatively without steroid administration. She had a good recovery except for mild residual renal insufficiency (sCr, 1.0 mg/dL). Although granuloma formation has been observed in kidney biopsy specimens of rare cases with DIHS, no previous studies have reported on the relationship between arterioles and granuloma formation
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