3,892 research outputs found
Recommended from our members
Intermodal connectivity and its impacts on HSR ridership : Seoul Station and Yongsan Station, South Korea
textSouth Korea launched its first high-speed rail (HSR) system in 2004. The primary goal of developing the system was to serve the citizens with improved regional mobility. The government has also invested a large amount of capital in providing amenities and convenience to passengers for the purpose of increasing HSR ridership; improving intermodal connectivity is among the efforts taken by the government and related agencies Yet whether improved intermodal connectivity translates into increased HSR ridership remains under-documented and under-researched. . This professional report examines the question by focusing on two HSR stations in the South Koreea case: Seoul Station and Yongsan Station. This report first presents the basis information about Korean HSR and the stations. It then documents government programs pertaining to intermodal connectivity. For reference purposes, a number of international cases are also reviewed and presented. Lastly, the PR examines the relationship between intermodal connectivity and HSR ridership and offers policy recommendations aiming at increasing ridership and enhancing services.Community and Regional Plannin
Diluting the inflationary axion fluctuation by a stronger QCD in the early Universe
We propose a new mechanism to suppress the axion isocurvature perturbation,
while producing the right amount of axion dark matter, within the framework of
supersymmetric axion models with the axion scale induced by supersymmetry
breaking. The mechanism involves an intermediate phase transition to generate
the Higgs \mu-parameter, before which the weak scale is comparable to the axion
scale and the resulting stronger QCD yields an axion mass heavier than the
Hubble scale over a certain period. Combined with that the Hubble-induced axion
scale during the primordial inflation is well above the intermediate axion
scale at present, the stronger QCD in the early Universe suppresses the axion
fluctuation to be small enough even when the inflationary Hubble scale
saturates the current upper bound, while generating an axion misalignment angle
of order unity.Comment: 5 pages, 1 figure; v2: discussion extended, references added, typos
correcte
Higgs phenomenology in the Peccei-Quinn invariant NMSSM
We study the Higgs phenomenology in the Peccei-Quinn invariant NMSSM
(PQ-NMSSM) where the low energy mass parameters of the singlet superfield are
induced by a spontaneous breakdown of the Peccei-Quinn symmetry. In the generic
NMSSM, scalar mixing among CP-even Higgs bosons is constrained by the observed
properties of the SM-like Higgs boson, as well as by the LEP bound on the
chargino mass and the perturbativity bound on the singlet Yukawa coupling. In
the minimal PQ-NMSSM, scalar mixing is further constrained due to the presence
of a light singlino-like neutralino. It is noticed that the excess of
the LEP events at 98 GeV can be explained by a
singlet-like 98 GeV Higgs boson in the minimal PQ-NMSSM with low ,
stops around or below 1 TeV, and light doublet-higgsinos around the weak scale.Comment: 31 pages, 4 figures; v2: references added, light stop effects
discussed, bound on the Higgs invisible decay rate correcte
Analysis of the tourist movement patterns of Jeju Island, Republic of Korea
El Big Data es una de las herramientas más utilizadas en la actualidad para la gestión de las actividades turísticas. Su incorporación en el análisis de los patrones de desplazamiento de visitantes se hace esencial tanto para caracterizar el interés de los visitantes con respecto a ciertos lugares, o para la planificación de la movilidad regional. Este estudio identifica y analiza varias características de la actividad turística en la isla de Jeju (Corea del Sur). Como unidades de análisis se utilizan los puntos de interés (POIs, definidos como lugares con especial concentración de visitantes). Para ello se han analizado los patrones de movimiento, tanto de turistas como de residentes.
La fuente de datos para identificar los POIs han sido los puntos calientes deducidos de la concentración de fotografías georreferenciadas de la plataforma Flickr, realizadas en la isla de Jeju entre los años 2010 y 2019 por los usuarios de esa plataforma. A partir del análisis de estos datos se ha incrementado el conocimiento de la actividad turística del área identificando las preferencias y tendencias de las visitas y los patrones espaciales y temporales que revelan los lugares más visitados dentro del área de estudio.
Este mejor conocimiento se puede usar para una planificación y gestión más inteligente de la actividad de los destinos turísticos, permitiendo tanto a las autoridades como a las industrias turísticas, ofrecer servicios mejores, más adecuados a la demanda y compatibles con los criterios de sostenibilidad que se determinen.
En el caso de estudio, se pone de manifiesto la tendencia de viajes de tipo ‘staycations’ (en los que el visitante viaja cerca de su domicilio habitual). Los POIs más representativos de Jeju son: el Pico Seongsanilchulbong, el Cabo Seopjikoji, Museo de Teddy Bear y las Cascadas Cheonjiyeon. Las zonas más visitadas son: el centro de las ciudades de Jeju y Seogwipo, el Centro Turístico Jungmun y el Pico Seongsanilchulbong y sus alrededores.
Así mismo, este estudio ha permitido proponer nuevas rutas para el autobús turístico que presta servicio en las ciudades de Jeju y Seogwipo, respectivamente, para optimizar la movilidad turística sin dañar la calidad del medio ambiente.Big Data is one of the most widely utilized tools for the efficient tourism management. The use of Big Data in the analysis of the movement patterns becomes essential for both characterizing the visitor preferences with respect to Points of interest (POIs, defined as specific point locations that people may find attractive and interesting) and facilitating interregional mobility. This study identifies various characteristics of tourism activity and spatio-temporal patterns on Jeju Island (South Korea). For this purpose, the movement patterns of both tourists and residents have been analyzed. The data has been collected from the georeferenced photos on Flickr, taken on Jeju Island between 2010 and 2019 by users of this photo-sharing platform.
The paper explores the tourism trend of ‘staycations’, which means a tendency of the frequent trip to local attractions near their home (Oxford, 2021). The most representative POIs in Jeju Island are: Seongsan Ilchulbong Peak, Seopjikoji, Teddy Bear Museum and Cheonjiyeon Falls. The most popular areas are: the center of Jeju City and Seogwipo City, Jeju Jungmun Resort, Seongsan Ilchulbong Peak and its surrounding area.
Moreover, this study proposes new routes for the city tour bus in Jeju City and Seogwipo City, respectively to strengthen the environmental sustainability and effective implementation by optimizing tourist mobility through the network analysis.
The methodology and strategic vision of this study feature significantly in the approach to their management plans of sustainable tourism for other local government, tourism industry and organization as well.Depto. de GeografíaFac. de Geografía e HistoriaTRUEunpu
End-to-End Learnable Multi-Scale Feature Compression for VCM
The proliferation of deep learning-based machine vision applications has
given rise to a new type of compression, so called video coding for machine
(VCM). VCM differs from traditional video coding in that it is optimized for
machine vision performance instead of human visual quality. In the feature
compression track of MPEG-VCM, multi-scale features extracted from images are
subject to compression. Recent feature compression works have demonstrated that
the versatile video coding (VVC) standard-based approach can achieve a BD-rate
reduction of up to 96% against MPEG-VCM feature anchor. However, it is still
sub-optimal as VVC was not designed for extracted features but for natural
images. Moreover, the high encoding complexity of VVC makes it difficult to
design a lightweight encoder without sacrificing performance. To address these
challenges, we propose a novel multi-scale feature compression method that
enables both the end-to-end optimization on the extracted features and the
design of lightweight encoders. The proposed model combines a learnable
compressor with a multi-scale feature fusion network so that the redundancy in
the multi-scale features is effectively removed. Instead of simply cascading
the fusion network and the compression network, we integrate the fusion and
encoding processes in an interleaved way. Our model first encodes a
larger-scale feature to obtain a latent representation and then fuses the
latent with a smaller-scale feature. This process is successively performed
until the smallest-scale feature is fused and then the encoded latent at the
final stage is entropy-coded for transmission. The results show that our model
outperforms previous approaches by at least 52% BD-rate reduction and has
to times less encoding time for object detection. It is
noteworthy that our model can attain near-lossless task performance with only
0.002-0.003% of the uncompressed feature data size.Comment: Under peer review for IEEE TCSV
Ability of γδ T cells to modulate the Foxp3 T cell response is dependent on adenosine.
Whether γδ T cells inhibit or enhance the Foxp3 T cell response depends upon their activation status. The critical enhancing effector in the supernatant is adenosine. Activated γδ T cells express adenosine receptors at high levels, which enables them to deprive Foxp3+ T cells of adenosine, and to inhibit their expansion. Meanwhile, cell-free supernatants of γδ T cell cultures enhance Foxp3 T cell expansion. Thus, inhibition and enhancement by γδ T cells of Foxp3 T cell response are a reflection of the balance between adenosine production and absorption by γδ T cells. Non-activated γδ T cells produce adenosine but bind little, and thus enhance the Foxp3 T cell response. Activated γδ T cells express high density of adenosine receptors and have a greatly increased ability to bind adenosine. Extracellular adenosine metabolism and expression of adenosine receptor A2ARs by γδ T cells played a major role in the outcome of γδ and Foxp3 T cell interactions. A better understanding of the functional conversion of γδ T cells could lead to γδ T cell-targeted immunotherapies for related diseases
Hepatocellular Carcinoma Arising in a Huge Hepatocellular Adenoma with Bone Marrow Metaplasia
Hepatocellular adenoma (HCA) is the most common type of benign liver tumor, and its major complication is malignant transformation to hepatocellular carcinoma (HCC). Here, we report a case of HCC arising in HCA with bone marrow metaplasia in a 24-year-old Korean woman who presented with abdominal discomfort. A huge liver mass was found on abdominal ultrasonography. She underwent surgical hepatic resection, and the resected specimen was entirely involved by a 20-cm-sized tumor. Histological review revealed a well differentiated HCC arising from inflammatory HCA with β-catenin nuclear positivity and bone marrow metaplasia that contained hematopoietic cells. This case was unique because malignant transformation, inflammatory type HCA, β-catenin nuclear staining, and bone marrow metaplasia were simultaneously observed. Additionally, it should be noted that a large HCA with β-catenin activation can undergo malignant transformation and should be surgically resected in a timely manner
- …