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Pandemic Simulations by MADE: A Combination of Multi-agent and Differential Equations, with Novel Influenza A(H1N1) Case
Get PDFTwo pandemic simulation approaches are known: the multi-agent simulation model and the differential equation model. The multi-agent model can deal with detailed simulations under a variety of initial and boundary conditions with standard social network models; however, the computing cost is high. The differential equation model can quickly deal with simulations for homogeneous populations with simultaneous ordinary differential equations and a few parameters; however, it lacks versatility in its use.We propose a new method named the MADE which is a combination of these two models, such that we use the multi-agent model in the early stage in a simulation to determine the parameters that can be used in the differential equation model, and then use the differential equation model in the subsequent stage. With this method, we may deal with pandemic simulations for real social structures with lower computing costs. Contrary to the statistical inference method which could not predict the final stage unless abundant information is included, the MADE have a possibility to do that only with the earlier stage information. The newly emerged pandemic, the novel influenza A(H1N1) case in 2009, is dealt with
Preparation and in vitro apatite-forming ability of porous and non-porous titania microspheres
No full textPorous and non-porous titania microspheres with the anatase or rutile phase were successively prepared by the sol–gel process followed by heat treatment at various temperatures. The pore size of the prepared microspheres was effectively controlled by incorporating silica nanoparticles of different diameters. The apatite-forming ability of the microspheres was investigated in a simulated body fluid, with ion concentrations nearly equal to those of human blood plasma. Results indicated that the titania microspheres with either anatase or rutile structure induced the formation of calcium phosphate compounds (CaPs) on the microsphere surface. The deposition of CaPs was more pronounced on the TiO2 microspheres calcined at 600°C (anatase structure) and 800°C (rutile structure), compared to that calcined at 500°C (anatase structure). Additionally, anatase microspheres with smooth surface and low specific surface area favored the formation of CaPs, compared to porous microspheres. This indicates that nanoscale pores do not essentially favor apatite formation
Effect of Ammonia or Nitric Acid Treatment on Surface Structure, in vitro Apatite Formation, and Visible-Light Photocatalytic Activity of Bioactive Titanium Metal
Get PDFTi metal treated with NaOH, NH4OH, and heat and then soaked in simulated body fluid (SBF) showed in vitro apatite formation whereas that treated with NaOH, HNO3, and heat and then soaked in SBF did not. The anatase TiO2 precipitate and/or the fine network structure formed on the surface of the Ti metal treated with NaOH, NH4OH, and heat and then soaked in SBF might be responsible for the formation of apatite on the surface of the metal. The NaOH, NH4OH, and heat treatments might produce nitrogen-doped TiO2 on the surface of the Ti metal, and the concentration of methylene blue (MB) in the Ti metal sample treated with NaOH, NH4OH, and heat decreased more than in the untreated and NaOH- and heat-treated ones. This preliminary result suggests that Ti metal treated with NaOH, NH4OH, and heat has the potential to show photocatalytic activity under visible light
Biomineralization on chemically synthesized collagen containing immobilized poly-γ-glutamic acid
No full textChemically synthesized collagen with a triple helix structure similar to that of natural collagen is attractive as a safe biomaterial. Hybrids of chemically synthesized collagen and apatite are proposed for novel bone substitutes. However their apatite-forming ability in simulated body fluid is still quite low. We examined acceleration of apatite formation on collagen by immobilized poly-γ-glutamic acid (PGA), which has excellent apatite-forming ability. Apatite was formed within 3 days when collagen was treated with PGA solutions containing an appropriate amount of CaCl2. A mixture of apatite and calcite was formed at high CaCl2 concentration. The present results indicate the possibility of preparing hybrid materials, with tailored mechanical and biological properties, based on chemically synthesized collagen
Quasi-Phase-Matched Second-Harmonic Generation in Thermally Poled Twin-Hole Silica-Glass Optical Fiber: Comparison between Mercury Lamp and Excimer Laser Exposures
Get PDFThe 8th International Symposium on Transparent Oxide and Related Materials for Electronics and Optics(TOEO-8), May 13-15, 2013, International Conference Center, Waseda University, Tokyo, Japa
統計的形状モデルの構築法とその医用画像上の臓器領域のセグメンテーションへの応用に関する研究
No full text九州工業大学博士学位論文（要旨） 学位記番号:工博甲第353号 学位授与年月日:平成25年9月27
Improvement of JPEG compression efficiency using information hiding and image restoration
Get PDFThe application of information hiding to image compression is investigated to improve compression efficiency for JPEG color images. In the proposed method, entropy-coded DCT coefficients of chrominance components are embedded into DCT coefficients of the luminance component. To recover an image in the face of the degradation caused by compression and embedding, an image restoration method is also applied. Experiments show that the use of both information hiding and image restoration is most effective to improve compression efficiency
Cerebrovascular Segmentation from CTA and MRA Image
Get PDF電子情報通信学会 ライフインテリジェンスとオフィス情報システム研究会（LOIS）、画像工学研究会（IE）、マルチメディア情報ハイディング・エンリッチメント研究会（EMM）, 09月12-13日, 2013年, 東海大学熊本キャンパス, 熊本がんに対する治療法の一つとして放射線療法がある.放射線療法とは,腫瘍部に対して放射線を照射する治療法である.放射線治療では,正常組織の放射線被ばくを抑え,腫瘍部にのみ放射線を照射する必要がある.このような腫瘍位置の把握にはCT,MRなどの画像が用いられるが,各画像を重ね合わせて表示することにより,腫瘍位置を効果的に表示可能となる.画像間の重ね合わせについては,画像内の特徴点の情報を用いたものが代表的なものとしてあげられる.本稿では,放射線療法の対象のひとつである脳腫瘍の治療における,画像重ね合わせに用いる特徴点として,CTAおよびMRA画像から脳血管領域を抽出するための手法を提案する.頭部実CTA・MRA画像に対して提案手法を適用し,その有用性について検討した
Study on Heat and Mass Transfer and Damage Mechanism During Dehydro-Freezing of Tissues
No full text九州工業大学博士学位論文 学位記番号:工博甲第343号 学位授与年月日:平成25年3月25日第1章 序章||第2章 マイクロ波デハイドロフリージングによる凍結魚肉組織の冷凍・解凍特性||第3章 魚肉組織の冷凍過程における数値解析と実験との比較||第4章 魚肉組織由来溶液の溶質分配係数の測定||第5章 魚肉組織の冷凍過程における細胞収縮と細胞ダメージとの関係||第6章 凍結魚肉組織の解凍過程における水分の再結晶化||第7章 組織細胞内における氷晶成長速度の実験評価||第8章 総
ペロブスカイト型酸化物を用いたインピーダンス検出型炭化水素ガスセンサに関する研究
No full text九州工業大学博士学位論文（要旨） 学位記番号:工博甲第347号 学位授与年月日:平成25年3月25