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Customized Network Security for Cloud Service
Get PDFapplication/pdfModern cloud computing platforms based on virtual machine monitors (VMMs) host a variety of complex businesses which present many network security vulnerabilities. In order to protect network security for these businesses in cloud computing, nowadays, a number of middleboxes are deployed at front-end of cloud computing or parts of middleboxes are deployed in cloud computing. However, the former is leading to high cost and management complexity, and also lacking of network security protection between virtual machines while the latter does not effectively prevent network attacks from external traffic. To address the above-mentioned challenges, we introduce a novel customized network security for cloud service (CNS), which not only prevents attacks from external and internal traffic to ensure network security of services in cloud computing, but also affords customized network security service for cloud users. CNS is implemented by modifying the Xen hypervisor and proved by various experiments which showing the proposed solution can be directly applied to the extensive practical promotion in cloud computing.journal articl
低品質条件で作製された繊維材混合流動化処理土の強度・変形特性に関する研究
Get PDF室蘭工業大学Muroran Institute of Technology博士（工学）application/pdf現在，環境の悪化は世界のさまざまな地域で深刻な問題になっている。特に発展途上地域の国々は，急速な都市の建設と開発に起因する環境問題に苦しんでいる。 都市建設の際，大量の建設廃土が発生し，その建設発生土に再利用については，そのままの状態では埋戻し土として適切さない場合や環境に悪影響を及ぼす可能性がある。この問題を解決するため，わが国では，建設発生土にセメント系固化材や生石灰などを混合した改良土を用いて再利用している。この技術は，現在，掘削工事現場の埋戻し土として用いられる流動化処理土工法として広く普及し，環境負荷の軽減に対して貢献しているが，その力学特性については未解明な部分が多い。現在，わが国，建設発生土の再利用方法の一つとして用いられる流動化処理土は，セメント改良土に分類されるが，セメント添加量を増加すると，強度と剛性も増加するが，脆性的な特性も増加するため，粘り強い地盤とはならず，地震時に問題が生じる可能性がある。そこで，過去の研究において，流動化処理土の脆性を改善するために，新聞紙を粉砕して綿のように加工した繊維材を混合した繊維材混合流動化処理土に関する一連の研究が行われ，ピーク後の脆性的な性質が改善されることが報告されている。一方，流動化処理土を開削トンネルの埋戻し材として適用する場合，土かぶり圧を軽減するために，強度低下を考慮しつつ，配合設計基準図の範囲内で比較的小さい泥水密度で作製された流動化処理土を用いる場合がある。しかし，この低品質条件で作製された流動化処理土の力学特性については未解明な部分が多く，強度，剛性，耐久性などの力学特性に問題が生じ，品質が低下する可能性があると考えられる。低品質な条件で作製された流動化処理土は，比較的小さな泥水密度で作製されるが，強度・変形特性に及ぼす泥水密度の影響については，まだ明らかにされていない。本研究の目的は，繊維材とセメント添加量が異なる流動化処理土の供試体を対象として，強度・変形特性に及ぼす泥水密度の影響を検討することである。したがって，本研究では，一連の三軸圧縮試験を実施するとともに，地表面付近の埋戻し材としての適用を想定した力学特性の把握のために，一軸圧縮試験を実施した。試験に用いる供試体の作製条件は，泥水密度が1.216，1.280 g/cm3，セメント添加量が80，100 kg/m3，繊維材混合量が0，10 kg/m3である。また，養生時間は28日および56日とした。試験結果より，泥水密度のわずかな減少でも流動化処理土の強度は著しく減少すること，低泥水密度で作製された流動化処理土に繊維材を混合することで，せん断による局部損傷や脆性的性質が改善されることなどが示された。以上より，現在，施工条件によっては実務に適用されている低品質の流動化処理土には問題があることが明らかにされるとともに，その流動化処理土に繊維材を混合することで強度・変形特性が改善されることが示された。Nowadays, Environment degradation is growing into a grave concern in various parts of the world. Countries especially in developing regions are suffering from environmental problems emanating from the rapid urban constructions and development. During urban constructions, tremendous amount of construction waste soils is generated which might not be suitable for reuse in constructions but on the other hand may be harmful to the environment if not treated appropriately. In order to solve this problem, some countries like Vietnam and Japan are making attempts to recycle this kind of waste soil by mixing it with solidification agent like cement or gypsum. This kind of recycling alleviated the pressure on the environment to some extent but there still has a lot of uncertain part of the mechanical property of the recycled soil. As one of the recycled materials, the Liquefied Stabilized Soil is widely used in Japan currently. However, as a cement solidified material, the adding of cement content will surely increase the stiffness and strength while the problem of brittleness must be considered in terms of its seismic behavior. On the other hand, in order to reduce the overburden pressure when the LSS is used as a backfill soil for cut and cover tunnel etc., there is a concern about the use of the LSS prepared with a relatively lower slurry density with considering the strength reduction. However, it is considered that some problem might arise for the quality of LSS on the strength, stiffness, durability and so on. In the past, in order to improve the brittle property of the LSS, a series of studies on the Liquefied Stabilized Soil mixed with newspaper prepared like cotton wool as the fiber material was carried out, and it was reported that the brittle property after the peak is improved due to the reinforcing effect of the fiber. However, as for decreasing the overburden pressure by preparing the LSS in lower slurry density, it is still not clear about the influence of reduction of slurry density. The purpose of this study is to investigate the influence of reduction of slurry density while preparing the Liquefied Stabilized Soil specimens with different cement content that mixed with fibers. Therefore in this study, a series of triaxial compression tests and unconfined compression tests were conducted on LSS specimens prepared in different slurry densities of 1.216, 1.280 g/cm3, cement contents of 80, 100 kg/m3 and the fiber contents of 0, 10 kg/m3 with different curing time of 28 and 56 days respectively. The results of undrained triaxial tests showed that slight decrease of slurry density can decrease the peak stress of LSS remarkably. Meanwhile, the changing in cement content can affect peak strength as well as the decreasing rate of Etan/E0 in the early loading stage. In addition, by adding fiber material, the local damage caused by shearing and the brittleness were improved. Based on these results of the triaxial tests and unconfined compression tests, the influences of changing in slurry density, as well as added amount of fiber on the triaxial shear properties of the LSS with different cement contents, are discussed in detail.doctoral thesi
Scallop mantle toxin induces apoptosis in liver tissues of mice
Get PDFapplication/pdfWe had previously shown that the intake of scallop mantle tissue resulted in the death of mice and rats. In this study, we investigated the liver injury caused by mantle tissue to clarify the mechanism behind its toxicity. Mantle toxin increased lipid peroxidation and decreased the reductive thiol content as well as the DPPH radical scavenging activity, catalase activity, and glutathione content in the liver of the mice. These results suggested that the mantle tissue diet caused oxidative stress through the decrease in antioxidants. In addition, mantle toxin increased the mRNA expression of endoplasmic reticulum (ER) stress- and inflammation-induced genes and the protein expression of caspase-3 and Bax (which induce apoptosis), suggesting that the mantle tissue diet causes apoptosis through oxidative stress, ER stress, and inflammation in the liver tissue. Such liver injury may be an essential cause of the rodent demise.journal articl
Re cent Desymmetrization Reactions By CALB
Get PDFapplication/pdfEnzyme reactions are among the most environmentally friendly and important asymmetric reactions for organic synthesis. Candida Antarctica lipase B (CALB) is one of the most extensively utilized enzymes for various asymmetric reactions. It catalyzes a variety of asymmetric reactions, such as hydrolysis, esterification, and amidation. However, as the studies of desymmetrization reactions of symmetric compounds catalyzed by CALB is rather limited, this commentary focuses on some recent examples of desymmetrization reactions mediated by CALB.journal articl
The Longitudinal Research of Students' Psychosomatic Influence after Hokkaido East Iburi Earthquake in 2018
Get PDFapplication/pdfAfter Hokkaido East Iburi Earthquake, longitudinal research data (2 weeks, 1 month, 2 months and 6months later) by questionnaire of junior high and high school student in the affected area were investigated. Data shows high school student represent higher than junior high school student’s stress level. And stress level is decreasing according to time elapse, however after big after-shock, most of stress level become higher than after first-shock, especially irritative and feel illness response. Stressresponse is easy to recover by stressful same event even after 6 month later.特集departmental bulletin pape
Survey Report of the Iburi-Tobu Earthquake Disasters
Get PDFapplication/pdfIn 2018, an earthquake occurred in the Iburi-Tobu district in Hokkaido, Japan, and caused severe disasters. This paper describes the results of field surveys of the Iburi-Tobu district. The results of field surveys provide invaluable information for mitigating future natural disasters in Hokkaido.特集departmental bulletin pape
都市の持続可能性に向けた旅行行動と知的移動データ統合に関する包括的研究
Get PDF室蘭工業大学Muroran Institute of Technology博士（工学）application/pdf過去数十年にわたり世界中で都市の持続可能性がトレンドとなり研究対象となっている．人々は，非効率な天然資源の消費や社会経済活動による環境破壊など，地球環境に有害な活動を行い，これには都市計画や交通計画を始め，多くの分野が密接に関係している．現在では，これらを解決する新技術の開発や応用が広範囲な研究分野で日々取り組まれている．本研究では観光に関する問題を，交通と都市の研究の観点からさまざまなビックデータを使用し，持続可能な都市開発を目標とした具体的な解決策を示した．本研究では都市や地域の持続可能性に資するデータの活用方法として，Wi-Fiパケットセンサーを使用した旅行者にとって魅力的な観光目的地マネジメントに関する研究，およびETCプローブデータを使用した旅行時間の信頼性の観測における天候の影響に関する分析を組み合わせて示した．本論文では，都市の移動性の認知に対して以下に示す3つの研究から，特徴的な結果と有効な分析手法を確立した．1）Wi-Fiパッケージセンシング調査を使用した，広域観光エリアでの周遊パターンのマイニングベースの関連法則の調査，2）Wi-Fi追跡データでの大規模な観光地の持続可能な開発に向けた魅力的な目的地の抽出，3）ETC2.0プローブデータを使用して，様々な道路タイプを考慮した旅行の信頼性に対する降雪の影響の評価．以上の研究から，複数視点の考察を積み重ね，包括的な評価と提案を行い，いくつかの重要な結果が得られた．この論文の貢献は，より良い社会への問題解決への糸口となり，今後の政策立案者にとって有意義な内容となるだろう．According to sustainability, the trend is spreading out around the world for past decades. There are many area subjects involved, such as city planning, transportation planning, and so on, because people realized human activities harmful to the environment by consuming natural resources with less efficiency process or damage environment by social and economic movements. Currently, emerging technologies considered for the proactive procedure in extensive study areas regarding new technology application and knowledge based. In term of transport and urban study, including tourism concerns, we used intelligent data from deferent sources to be demonstrating the possible solutions which involve sustainable urban development concept. In this study, as a method of utilizing data that contributes to the sustainability of cities and regions, consideration of attractive destination management for tourists by using wireless probe data, and the weather impact on travel time reliability observation by using electronic toll collection probe data, it represented as combination experiments throughout comprehensive study. This dissertation addressed three contribution studies to the composed acknowledgment of urban mobility, and it obtained the intelligent data and specific method of research-based. It consists of; 1) an association rule mining-based exploration of travel patterns in wide tourism areas using a Wi-Fi package sensing survey, 2) Attractive destinations mining towards massive tourism area sustainable development on Wi-Fi tracking data, and 3) Assessment of the impact of snowfall on travel reliability considering different road types using ETC2.0 probe data. Hence, a stack of varying viewpoints researches provided a comprehensive review and suggestion throughout significant results. The contribution of this dissertation could be an advantage substance for strategy and policies planner to recognize alternative solutions leading to a better society.doctoral thesi
Daurichromenic Acid from the Chinese Traditional Medicinal Plant Rhododendron dauricum Inhibits Sphingomyelin Synthase and Aβ Aggregation
Get PDFapplication/pdfSpecies of the genus Rhododendron have been used in traditional Chinese medicine, with the medicinal herb “Manshanfong” used as an expectorant and for the treatment of acute bronchitis. Daurichromenic acid (DCA), a constituent of Rhododendron dauricum, is a meroterpenoid with antibacterial, anti-HIV, and anti-inflammatory activities. However, the mechanisms underlying these pharmacologic activities are poorly understood. To develop new drugs based on DCA, more information is required regarding its interactions with biomolecules. The present study showed that DCA inhibits the activity of the enzyme sphingomyelin synthase, with an IC50 of 4 µM. The structure–activity relationships between DCA and sphingomyelin synthase were evaluated using derivatives and cyclized hongoquercin A. In addition, DCA was found to inhibit amyloid β aggregation. These results may help in the design of effective drugs based on DCA.journal articl
車両のエッジコンピューティングにおけるネットワークリソースの最適化手法
Get PDF室蘭工業大学Muroran Institute of Technology博士（工学）application/pdf車両インターネット（IoV）の発展伴い、インテリジェント交通サービスやインフォテインメントサービスなど、多くのIoVサービスが人々の生活に浸透してきている。IoVの出現は、ドライバーに革新的で便利なサービスを提供するが、大規模なデータ処理には不向きである。従来のIPネットワークとは異なり、車両ネットワークの無線リンクは低品質かつ切れやすいため、タスク処理のためにクラウドへ大量のデータ伝送をすることは現実的でない。車両エッジコンピューティングネットワーク（VECN）は、これらのタスクを車両に近いエッジノードにオフロードすることにより、高速にタスク処理をする有望な方法である。VECNアーキテクチャには2つの難点がある。1つは、車両エッジノードのコンピューティングリソースが限られているため、軽量なアルゴリズムの開発が必要である。 もう1つは、一部のエッジノードと車両が同じパーティーに属していないことがあるため、合理的な資源割当が必要である。本論文では、まず、機械学習のブロードラーニングを用いて車両エッジコンピューティングネットワークにおける軽量トラフィック分析システムを提案する。そしてVECNでの公平なリソース割り当て問題を解決するため、マルチ属性に基づくダブルオークションメカニズムを設計する。次に、VECNシナリオでユーザーのダイナミクスを満たすオンラインオークションメカニズムを提案する。このメカニズムは、買いユーザーと売りユーザーのマッチングを構築するときに非価格属性も考慮する。最後に、提案されたスキームを検証するためにシミュレーション実験ならびに実機実験を行った。With the development of the Internet of Vehicles (IoV), more and more vehicular services are coming to people’s daily life, including intelligent transportation services and infotainment services. While the emergence of numerous services could provide innovative and convenient services for drivers, how to process large-scale data effectively still needs in-depth research in the IoV scenario. Different from traditional networks, the vehicular network has poor-quality wireless links which may lead to poor communication quality. Therefore, moving data to the cloud for processing is not feasible in the vehicular network. Vehicular edge computing network (VECN) is a promising way to provide fast task processing services for vehicles by offloading these tasks to edge nodes close to vehicles. There are two challenges in the VECN architecture: one is that vehicular edge nodes always have limited computing resources. Therefore, lightweight algorithms need to be deployed to promote the development of VECN. And the other is that some edge nodes and vehicles do not belong to the same party. Therefore, how to conduct fair trade between them for providing reasonable resource allocation is an important issue. In this dissertation, we firstly propose the broad learning based lightweight traffic analysis system in the vehicular edge computing network. Secondly, a multi-attribute based double auction mechanism is designed to solve the problems of fair resource allocation in the VECN. Then we propose an online auction mechanism to satisfy the dynamics of users in the VECN scenario, which also considers the non-price attributes when constructing the matching between buyers and sellers. Finally, we conduct multiple experiments to verify the proposed schemes.doctoral thesi
A Study on Function-Expansion-Based Topology Optimization without Gray Area for Optimal Design of Photonic Devices
Get PDFapplication/pdfIn this paper, we reformulate a sensitivity analysis method for function-expansion-based topology optimization method without using gray area. In the conventional approach based on function expansion method, permittivity distribution contains gray materials, which are intermediate materials between core and cladding ones, so as to let the permittivity differentiable with respect to design variables. Since this approach using gray area dose not express material boundary exactly, it is not desirable to apply this approach to design problems of strongly guiding waveguide devices, especially for plasmonic waveguides. In this study, we present function-expansion-method-based topology optimization without gray area. In this approach, use of gray area can be avoided by replacing the area integral of the derivative of the matrix with the line integral taking into acount the rate of boundary deviation with respect to design variables. We verify the validity of our approach through applying it to design problems of a T-branching power splitter and a mode order converter.journal articl