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河道の変化に起因する河道災害の対策手法に関する研究
Get PDF北見工業大学博士（工学）北海道東部に位置する音更川では，平成23 年9 月に発生した出水によって流路が大きく蛇行して堤防の一部が流失し，流路変動に対する堤防の脆弱性が明らかになった．流路変動から堤防を防護するためには，出水時における蛇行流路や砂州の変化特性を踏まえた対策を計画することが求められたが，実際の河川における出水時の蛇行流路や砂州形状の変化に関する知見が少なく，蛇行特性を考慮した河道計画の立案手法が確立されていない状況にあった．そのため，本研究は，砂州形成実験や砂州形状観測を行って出水時における砂州の形成過程や蛇行流路形状の変化特性を明らかにしたほか，それらの特性を考慮して河道計画を立案する手法について技術開発を行ったものであり，以下の研究成果が得られた．
1) 砂州形成実験によって，水深の変化に応じて砂州形態や砂州形状が変化することや，水位上昇期と低下期では水深の履歴効果をうけて砂州形態や砂州形状に違いが発生することを明らかにしたほか，それらの変化は非定常流下の線形安定解析により再現が概ね可能であることを示した．
2) 河川における出水時の砂州形状観測によって，単列砂州の減衰現象や複列砂州から単列砂州への移行現象などを明らかにしたほか，それらの砂州形態の変化が出水中の水理量の変化に応じて発生していることを線型安定解析により明らかにした．
3) 河川における出水時の蛇行発達は，洪水ピーク流量，水位波形，洪水継続時間，出水初期の流路形状の要因が影響を及ぼしていることを線型安定解析等により明らかにしたほか，音更川では蛇行流路が下流方向へ移動しながら蛇行振幅を増大させる変化特性を有していることを明らかにした．
4) 蛇行流路の変化特性から堤防の危険箇所を推定して堤防防護の対策区間を設定し，蛇
行振幅の最大発達量などの蛇行特性をもとに堤防防護計画を立案する手法を開発した．また，本計画に基づく対策の効果を検証し，その有効性を明らかにした．doctoral thesi
北見工業大学 技術部報告 第26号 平成30年度
Get PDF北見工業大学●技術部報告巻頭言に寄せて
国立大学法人北見工業大学技術部長 三上 修一●技術報告
・Raspberry Pi を使ってみました 1
情報処理支援グループ 宇野 珠実
・形態観察におけるデジタルマイクロスコープの活用 5
機器分析支援グループ 徳田 奨
・平成29 年度北海道地区国立大学法人等技術職員研修会の参加報告 7
ものづくり支援グループ 杉野 豪
・Excel VBA による作業の簡略化 12
環境安全支援グループ 須澤 啓一●学外研修・出張報告 20
●グループ研修報告 21
●研修会・講習会等参加状況 40
●地域貢献活動 42
●活動報告 44
●各種会議・委員会名簿 46research repor
OBSERVATION OF COLLIDING FORCE ON CONCRETE STRUCTURE WITH PROGRESS OF COMBINED DETERIORATION IN RIVER
Get PDFIn snowy cold region, many concrete structures in rivers are degraded by combination of freezing and salt damage. In some cases, collision of river ice cause additional damages on concrete structures in river channel. We conducted field observation to clarify relation between river ice movement and acting force on concrete piles set on the bank of Abashiri River. Acting force can be evaluated with approach rate, plane area, length and thickness of river ice. We estimated river thickness with bottom tracking of ADCP in field tests and confirmed good relations between estimated value and actual value. We observed acting forces on sheet piles and calculated stress coefficients of ice to investigate evaluation methods.journal articl
ビフィズス菌の抗菌性評価
Get PDF北見工業大学博士（工学）Antibacterial activity of Bifidobacteria isolated from Mongolian infant feces was elucidated on pathogenic intestinal bacteria for the development of a new antibacterial Bifidobacteria by permission of the Mongolian Medical Ethics Committee Approval (MMECA). Forty-nine single colonies were totally obtained from 3 samples by using an enrichment BL agar medium. Among them, 29 isolates had Gram−positive, catalase−negative properties, and maul−like or Y−shaped morphology, and then, 20 Bifidobacterium breve and 9 Bifidobacterium longum strains were detected by the B. breve and B. longum specific primers. Organic acids produced by the isolated Bifidobacteria in their cell free supernatants were quantitatively analyzed by a spectrophotometric absorbance at 340 nm, suggesting that D−lactic, L−lactic, and acetic acids were produced, and the pH of the supernatants was at 3.86−4.55. The isolated Bifidobacteria showed antibacterial activity toward Escherichia coli and Salmonella typhimurium as high as that of standard Bifidobacteria, however, lower activity against Staphylococcus aureus. The antibacterial activity was probably due to the production of the organic acids.
We aimed high antibacterial potential probiotic found for the development of a new antibacterial peptide. Thirty-six single colonies were totally obtained 15 samples of the faeces and rumen cud collected from Mongolian young livestock animals of around the three provinces (Tuv, Khovd, Khuvsgul). The 5-type species Bifidobacterium identified B.bifidum B.catenulatum, B.ruminantum, B.longum, B.pseudocatenulatum and 8 type species lactic acid bacteria Enterococcus alcedinis, Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus lactis, Enterococcus mundti, Lactobacillus reuteri, and Lactobacillus plantarum by 16S rDNA sequencing analysis.
Isolated from the lamb rumen B.bifidum (BBLA72) was produced 29.6 mmol per litres acetic acid and 19.3 mmol per litres of lactic acid, thereby releasing pH from 7.0 to 4.57. However, organic acids were produced small in comparison with other strains, the antibacterial activity of the pH neutralized up to 7.0 cell-free supernatant was more significant than other strains.
BBLA 72 starts with early stationary phase and its antibacterial activity is the highest in 18 hours of bacterial culture. In the pH stabilization, bacterial resistance to 1-10 was active and 5, 6, and 7 did not significantly reduce the antibacterial activity.
The arbitrary unit was measured 25600 AU/ml against to E.coli. It is preliminary for this substance as a bacteriocin-like substance that weighs 2 kDa and 5 kDa, capable of withstanding a 100-degree heat to 30 minutes, proteinase K and trypsin enzyme.モンゴルでは家畜に対して大量の抗生物質を投与し人の健康にも関わるため社会問題になっている。本研究では家畜用抗生剤に代わる安心安全な抗菌剤の開発を大きな目的に、ビフィズス菌が産生する有機酸や抗菌性ペプチドによる抗菌性について研究した。ビフィズス菌は、グラム陽性でカタラーゼ活性陰性の嫌気性腸内細菌の一種である。腸内環境を整えるために乳酸、酢酸などの有機酸を生成し、様々な生理機能を発揮する。産生された有機酸、酵素による分離同定、殺菌作用などビフィズス菌に関する多くの研究が報告されている。しかしビフィズス菌が生産する抗菌ペプチドについての研究は少ない。本研究の目的は、ビフィズス菌の抗菌性を明らかにして新しい抗菌性ペプチドを同定することにある。第2章ではモンゴル医療倫理委員会の許可の下、モンゴル人インファントから人ビフィズス菌の単離同定および有機酸による抗菌試験について検討した。第3章ではモンゴルのコプド、クプスグルおよびトゥブ州において家畜（子供）の第一胃および糞から、22のサンプルを収集し、抗菌性試験および抗菌ペプチドの単離を試みた。第1章は序論、第4章はまとめである。
第2章では、5名のモンゴル人インファントから菌として49シングルコロニーを単離し、そのうち29コロニーはグラム陽性、カタラーゼ活性陰性で棒状またはY字形状であった。これらは20コロニーはB. breve、9コロニーはB. longum菌であることをそれぞれ16S rDNAプライマーによるPCRによって明らかにした。培養上澄みに産生した有機酸を吸光光度分析(340nm) によって定量的に解析した。上澄みにはD—およびL-乳酸、酢酸が生成していることが分かり、E. coli、S. typhimuriumに対して高い抗菌性を示すことを見出した。この抗菌性は有機酸によるものと推定した。
第3章では、生まれて1ヶ月以内のヤギ、ラクダ、ヒツジ、ウサギなどの家畜22頭から試料を採取し、73のシングルコロニーを単離し、16Sr DNA汎用プライマーを用いて11のビフィズス菌を単離した。これらは有機酸による抗菌性を示したが;:pH7に中和したところ、LA72(B. bifidum)はSDS PAGE で2kDa と3kDa に2 本のバンドが現れ、これらはE. coliに対して25600AU/mlという高い抗菌性を示すことを見出した。プロテイナーゼKおよびトリプシン処埋するとバンドが消失し抗菌性も無くなることから抗菌性ペプチドと考えた。今後はこれらのペプチドの1次構造解析と大量培養による抗菌材料化、新たなビフィズス菌の探索などについて研究開発を続ける予定である。doctoral thesi
Symmetrical Patterns of Ainu Heritage and Their Virtual and Physical Prototyping
Get PDFThis article addresses virtual and physical prototyping of some symmetrical patterns
collected from the Ainu cultural heritage. The indigenous people living in the northern part of
Japan (e.g., Hokkaido), known as Ainu, often decorate their houses, clothing, ornaments, utensils,
and spiritual goods using some unique patterns. The patterns carry their identity as well as their
sense of aesthetics. Nowadays, dierent kinds of souvenirs and cultural artifacts crafted with Ainu
patterns are cherished by many individuals in Japan and abroad. Thus, the Ainu patterns carry both
cultural and commercial significance. A great deal of craftsmanship is needed to produce the Ainu
patterns precisely. There is a lack of human resources having such craftsmanship. It will remain
the same in the foreseeable future. Thus, there is a pressing need to preserve such craftsmanship.
Digital manufacturing technology can be used to preserve the Ainu pattern-making craftsmanship.
Fromthis perspective, this article presents a methodology to create both virtual and physical prototypes
of Ainu patterns using digital manufacturing technology. In particular, a point cloud-based approach
was adopted to model the patterns. A point cloud representing a pattern was then used to create a
virtual prototype of the pattern in the form of a solid CAD model. The triangulation data of each
solid CAD model were then used to run a 3D printer to produce a physical prototype (replica of
the pattern). The virtual and physical prototypes of both basic (Hokkaido) Ainu motifs and some
synthesized patterns were reproduced using the presented methodology. The findings of this study
will help those who want to digitize the craftsmanship of culturally significant artifacts without using
a 3D scanner or image processing.journal articl
Ｘ線ＣＴスキャンを活用した土の侵食抵抗試験に関する基礎的研究
Get PDFIn this study, the test equipment was manufactured by applying the sprayer, and the erosion resistance test was carried out. X-ray CT scan was used for interpretation of the test results, and not only the development state of the root system in the test specimen was grasped, but X-ray CT scan was also carried out after the test to determine the erosion depth and erosion rate.
The test results revealed that the erosion resistance increased as the root system developed. In addition, the root system quantity and erosion depth obtained from the X-ray CT scan image of the test specimen had a negative correlation, and it was found that the X-ray CT scan was useful as one of the methods for grasping the influence of the root system on the erosion resistance of soil.journal articl
Performance Evaluation of Precast Concrete Using Microwave Heating Form
Get PDFThe purpose of this study is to evaluate the temperature distribution, strength development, porosity, scanning electron microscopy observation, shrinkage, and surface properties of concrete in order to apply microwave heat curing to the precast method and to analyze the CO2 emissions and economic feasibility of microwave heat curing. The heating of a steel form by microwave heating enabled concrete to be efficiently cured at a temperature within a range of ±5 °C. After the curing, demolding strength could be cleared through the densification of the concrete by decreasing the porosity of the concrete. Microwave heat curing exhibited excellent performance compared to conventional steam curing in terms of efficient temperature control, occurrence of cracks due to shrinkage, surface condition of concrete after curing, economic efficiency, and CO2 emissions. However, verification and supplementation based on actual data are necessary so that environments applicable to the various sizes and shapes of forms can be prepared.journal articl
Shrinkage and Durability Evaluation of Environmental Load-Reducing FRPCM by Using Silicone Oil
Get PDFIn this study, the shrinkage and durability of environmental load-reducing fiber-reinforced polymer cement mortar (FRPCM) were examined by using silicone oil. The results indicated that the shrinkage can be greatly reduced by adding silicone oil. However, when the silicone oil is added in excess, it affects the strength and durability. Therefore, it is possible to obtain the ECO-FRPCM which gives the effect of reducing the shrinkage and maintaining the strength and durability by adding 3% of silicone oil. From the viewpoint of shrinkage reduction, the use of silicone oil is effective as a substitute for an expansive additive or shrinkage reducing agent used in ECO-FRPCM. Also, by appropriately using silicone oil in combination with an expansive additive or a shrinkage reducing agent, shrinkage can be effectively reduced as compared with the conventional ECO-FRPCM. However, when the silicone oil and the shrinkage reducing agent are used in combination, the shrinkage cannot be efficiently reduced. It is considered that the combination of silicone oil and shrinkage reducing agent influences the mutual shrinkage reduction mechanism, but this needs to be further examined in the future.journal articl
IVESTIGATIING REPORT OF RIVER STRACTURE DAMEGE AT NORTHEN AND EASTERN HOKKAIDO DUE TO HEAVY RAINFALL, JULY 2019
Get PDFIn Hokkaido, heavy rain in July 2018 was the largest flood since the heavy rain in Hokkaido in 2016. In small and medium-sized rivers in northern Hokkaido, damages such as breakage of levees and spillage of abutment back embankment occurred. In the eastern part of Hokkaido, a bridge spanning a first class river caused a subsidence of the bridge pier foundation. This paper presents basic data that will contribute to future disaster prevention measures regarding the results of the survey of the damage status of river structures that occurred in the Hokkaido and Eastern regions due to torrential rains in July 2018.journal articl
Vibration‐based structural state identification by a 1‐dimensional convolutional neural network
No full textDeep learning has ushered in many breakthroughs in vision‐based detection via convolutional neural networks (CNNs), but the vibration‐based structural damage detection by CNN remains being refined. Thus, this study proposes a simple one‐dimensional CNN that detects tiny local structural stiffness and mass changes, and validates the proposed CNN on actual structures. Three independent acceleration databases are established based on a T‐shaped steel beam, a short steel girder bridge (in test field), and a long steel girder bridge (in service). The raw acceleration data are not pre‐processed and are directly used as the training and validation data. The well‐trained CNN almost perfectly identifies the locations of small local changes in the structural mass and stiffness, demonstrating the high sensitivity of the proposed simple CNN to tiny structural state changes in actual structures. The convolutional kernels and outputs of the convolutional and max pooling layers are visualized and discussed as well.journal articl