Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Search Results: 1 - 10 of 323 matches for " Yuichiro; "
All listed articles are free for downloading (OA Articles)
Page 1 /323
Display every page Item
Reconciling Safety and Fairness in Global Agri-Food Standardization  [PDF]
Yuichiro Amekawa
Sociology Mind (SM) , 2013, DOI: 10.4236/sm.2013.31006

Private food safety standards have recently emerged as a dynamic power in the global value chan. Good agricultural practices (GAP) is one such standard currently gaining popularity as a prominent field-level food quality assurance system. Achieving private GAP certification, most notably of GlobalGAP, is a dif ficult option for low income producers in the Global South due to the high costs required for necessary investments and certification. This paper critically analyzes the ethical implications of private food safety standards in light of three theoretical perspectives from environmental sociology: ecological moderniza tion, risk society, and eco-socialism. It then examines the potential of public GAP schemes currently emerging in the Global South for reconciling safety and fairness in global agri-food standardization. It is suggested that the expansion of producer participation in public GAP program be regulated by gradual improvements in the state capacity of resource mobilization for auditing and extension institutions.

Identification of the Bacterial Gene in Patients Who Repeatedly Develop Streptococcal Pharyngitis  [PDF]
Yuichiro Tsuji, Ichihashi Izumi
International Journal of Clinical Medicine (IJCM) , 2012, DOI: 10.4236/ijcm.2012.37121

Background: We aimed at determining whether the pathogenic bacteria at the onset of disease are genetically different and whether this affects future choice of the therapeutic methods against group A β-hemolytic streptococcal acute pharyngitis/tonsillitis. Methods: A pharynx swab was collected from pediatric patients who visited our hospital. The swab was cultured, and hemolytic streptococcus was detected 230 times. We isolated pathogenic bacteria of patients infected more than once and examined the bacteria using pulse-field gel electrophoresis. Results: Based on gene search results, we found that if the period of developing relapse was within 1 month from the first infection, all patients had the same gene. However, all patients in whom reinfection occurred after 6 months or later had different pertinent genes. Conclusions: The number of relapse/reinfection is significant for this disease, and considerably caution is essential for its treatment. No changes to antibacterial drug administration may be necessary for the second administration unless more than 6 months have passed since the first infection.

Method of Searching for Earthquake Disaster Evacuation Routes Using Multi-Objective GA and GIS  [PDF]
Yuichiro Shimura, Kayoko Yamamoto
Journal of Geographic Information System (JGIS) , 2014, DOI: 10.4236/jgis.2014.65042
Abstract: This study treats the determination of routes for evacuation on foot in earthquake disasters as a multi-objective optimization problem, and aims to propose a method for quantitatively searching for evacuation routes using a multi-objective genetic algorithm (multi-objective GA) and GIS. The conclusions can be summarized in the following three points. 1) A GA was used to design and create an evacuation route search algorithm which solves the problem of the optimization of earthquake disaster evacuation routes by treating it as an optimization problem with multiple objectives, such as evacuation distance and evacuation time. 2) In this method, goodness of fit is set by using a Pareto ranking method to determine the ranking of individuals based on their relative superiorities and inferiorities. 3) In this method, searching for evacuation routes based on the information on present conditions allows evacuation routes to be derived based on present building and road locations. Further, this method is based on publicly available information; therefore, obtaining geographic information similar to that of this study enables this method to be effective regardless of what region it is applied to, or whether the data regards the past or the future. Therefore, this method has high degree of spatial and temporal reproducibility.
Construction Sequence of the Koh Ker Monuments Constrained by the Chemical Composition and Magnetic Susceptibility of Its Bricks  [PDF]
Etsuo Uchida, Yuichiro Sakurai
Archaeological Discovery (AD) , 2018, DOI: 10.4236/ad.2018.62009
Abstract: Using a portable X-ray fluorescence analyzer and magnetic susceptibility meter, we measured fired bricks from nine temples (Prasat Thom, Prasat Damrei, Prasat Chamreh, Prasat Krachap, Prasat Kraham, Prasat Chen, Prasat Banteay Pir Chan, Prasat Chrap, and Prasat Pram) of the Koh Ker monuments, Cambodia. Based on cluster analysis of the chemical compositional data for Ti, Fe, Rb, Y, and Zr, as well as magnetic susceptibility data, the brick buildings could be classified into four groups (Stages A to D). Taking into consideration the five construction stages (Stages ① to ⑤) defined by Uchida et al. (2014) for laterite buildings, and using the assumption that all buildings were basically constructed outwards from the center, we define a construction sequence for these brick buildings. Thus, the following chronological relationship was obtained for construction stages of both laterite and brick buildings: Stage A → Stages B & ① → Stages C & ② → Stages D & ③ → Stage ④ → Stage ⑤. We surmise that the Northern Libraries of Prasat Pram, Prasat Chen and Prasat Damrei were added after the construction of their Inner Enclosures.
An implementation of the microphysics in full general relativity : General relativistic neutrino leakage scheme
Yuichiro Sekiguchi
Physics , 2010, DOI: 10.1088/0264-9381/27/11/114107
Abstract: Performing fully general relativistic simulations taking account of microphysical processes is one of long standing problems in numerical relativity. One of main difficulties in implementation of weak interactions in the general relativistic framework lies on the fact that the characteristic timescale of weak interaction processes (the WP timescale) in hot dense matters is much shorter than the dynamical timescale. Numerically this means that stiff source terms appears in the equations so that an implicit scheme is in general necessary to stably solve the relevant equations. Otherwise a very short timestep will be required to solve them explicitly. Furthermore, in the relativistic framework, the Lorentz factor is coupled with the rest mass density and the energy density. The specific enthalpy is also coupled with the momentum. Due to these couplings, it is very complicated to recover the primitive variables and the Lorentz factor from conserved quantities. At the current status, no implicit procedure have been proposed except for the case of the spherical symmetry. Therefore, an approximate, explicit procedure is developed in the fully general relativistic framework in this paper as an first implementation of the microphysics toward a more realistic sophisticated model. The procedure is based on the so-called neutrino leakage schemes which is based on the property that the characteristic timescale in which neutrinos leak out of the system (the leakage timescale) is much longer than the WP timescale. In this paper, I present a detailed neutrino leakage scheme and a simple and stable method for solving the equations explicitly in the fully general relativistic framework. I also perform a test simulation to check the validity of the present method, showing that it works fairly well.
Stellar core collapse in full general relativity with microphysics - Formulation and Spherical collapse test -
Yuichiro Sekiguchi
Physics , 2010, DOI: 10.1143/PTP.124.331
Abstract: One of the longstanding issues in numerical relativity is to enable a simulation taking account of microphysical processes (e.g., weak interactions and neutrino cooling). We develop an approximate and explicit scheme in the fully general relativistic framework as a first implementation of the microphysics toward a more realistic and sophisticated modeling. In this paper, we describe in detail a method for implementation of a realistic equation of state, the electron capture and the neutrino cooling in a multidimensional, fully general relativistic code. The procedure is based on the so-called neutrino leakage scheme. To check the validity of the code, we perform a two dimensional (2D) simulation of spherical stellar core collapse. Until the convective activities set in, our results approximately agree, or at least are consistent, with those in the previous so-called state-of-the-art simulations. In particular, the radial profiles of thermodynamical quantities and the time evolution of the neutrino luminosities agree quantitatively. The convection is driven by negative gradients of the entropy per baryon and the electron fraction as in the previous 2D Newtonian simulations. We clarify which gradient is more responsible for the convection. Gravitational waves from the convection are also calculated. We find that the characteristic frequencies of the gravitational-wave spectra are distributed for higher frequencies than those in Newtonian simulations due to the general relativistic effects.
Parsing a sequence of qubits
Yuichiro Fujiwara
Mathematics , 2012, DOI: 10.1109/TIT.2013.2272695
Abstract: We develop a theoretical framework for frame synchronization, also known as block synchronization, in the quantum domain which makes it possible to attach classical and quantum metadata to quantum information over a noisy channel even when the information source and sink are frame-wise asynchronous. This eliminates the need of frame synchronization at the hardware level and allows for parsing qubit sequences during quantum information processing. Our framework exploits binary constant-weight codes that are self-synchronizing. Possible applications may include asynchronous quantum communication such as a self-synchronizing quantum network where one can hop into the channel at any time, catch the next coming quantum information with a label indicating the sender, and reply by routing her quantum information with control qubits for quantum switches all without assuming prior frame synchronization between users.
Even-freeness of cyclic 2-designs
Yuichiro Fujiwara
Mathematics , 2012,
Abstract: A Steiner 2-design of block size k is an ordered pair (V, B) of finite sets such that B is a family of k-subsets of V in which each pair of elements of V appears exactly once. A Steiner 2-design is said to be r-even-free if for every positive integer i =< r it contains no set of i elements of B in which each element of V appears exactly even times. We study the even-freeness of a Steiner 2-design when the cyclic group acts regularly on V. We prove the existence of infinitely many nontrivial Steiner 2-designs of large block size which have the cyclic automorphisms and higher even-freeness than the trivial lower bound but are not the points and lines of projective geometry.
Self-synchronizing pulse position modulation with error tolerance
Yuichiro Fujiwara
Mathematics , 2013, DOI: 10.1109/TIT.2013.2262094
Abstract: Pulse position modulation (PPM) is a popular signal modulation technique which creates M-ary data by means of the position of a pulse within a time interval. While PPM and its variations have great advantages in many contexts, this type of modulation is vulnerable to loss of synchronization, potentially causing a severe error floor or throughput penalty even when little or no noise is assumed. Another disadvantage is that this type of modulation typically offers no error correction mechanism on its own, making them sensitive to intersymbol interference and environmental noise. In this paper we propose a coding theoretic variation of PPM that allows for significantly more efficient symbol and frame synchronization as well as strong error correction. The proposed scheme can be divided into a synchronization layer and a modulation layer. This makes our technique compatible with major existing techniques such as standard PPM, multipluse PPM, and expurgated PPM as well in that the scheme can be realized by adding a simple synchronization layer to one of these standard techniques. We also develop a generalization of expurgated PPM suited for the modulation layer of the proposed self-synchronizing modulation scheme. This generalized PPM can also be used as stand-alone error-correcting PPM with a larger number of available symbols.
Using arbitrary parity-check matrices for quantum error correction assisted by less noisy qubits
Yuichiro Fujiwara
Mathematics , 2014,
Abstract: Recently a framework for assisted quantum error correction was proposed in which a specific type of error is allowed to occur on auxiliary qubits, which is in contrast to standard entanglement assistance that requires noiseless auxiliary qubits. However, while the framework maintains the ability to import any binary or quaternary linear code without sacrificing active error correction power, it requires the code designer to turn a parity-check matrix of the underlying classical code into an equivalent one in standard form. This means that classical coding theoretic techniques that require parity-check matrices to be in specific form may not fully be exploitable. Another issue of the recently proposed scheme is that the error correction capabilities for bit errors and phase errors are generally equal, which is not ideal for asymmetric error models. This paper addresses these two problems. We generalize the framework in such a way that any parity-check matrix of any binary or quaternary linear code can be exploited. Our generalization also allows for importing a pair of distinct linear codes so that error correction capabilities become suitably asymmetric.
Page 1 /323
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.