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水中環境における光学画像の画質改善に関する研究
No full text九州工業大学博士学位論文 学位記番号：工博甲第398号 学位授与年月日：平成27年9月25日1 INTRODUCTION||2 IMAGE ENHANCEMENT||3 COLOR CORRECTION||4 IMAGE SEGMENTATION||5 CONCLUSIONSSince the 1960s, autonomous underwater vehicles (AUVs) and unmanned underwater vehicles (UUVs) have been used for deep-sea exploration. Sonar sensors also have been extensively used to detect and recognize objects in oceans. Although sonar sensors are suitable for long-range distance imaging, due to the principles of acoustic imaging, sonar images are low signal to noise ratio, low resolution and no colors. In order to acquire more detail information of underwater object, a short-range imaging system is required. In this situation, a photo vision sensor is used reasonably.
However, the low contrast and color distortion of underwater images are still the major issues for practical applications. Therefore, this thesis will concentrate on the underwater optical images quality improvement.
Although the underwater optical imaging technology has made a great progress, the recognition of underwater objects is still a challenging subject nowadays. Different from the normal images, underwater images suffer from poor visibility due to the medium scattering and light distortion. First of all, capturing good quality images in underwater circumstance is difficult, mostly due to attenuation caused by light that is reflected from a surface and is deflected and scattered by particles. Secondly, absorption substantially reduces the light energy. The random attenuation of the light mainly causes the haze appearance along with the part of the light scattered back from the water. In particular, an underwater object which 10 meters away from camera lens is almost indistinguishable because of light absorption. Furthermore, when the artificial light is employed, it can cause a distinctive footprint on the seafloor.
In order to obtain high quality underwater images that can be adapted to the traditional image identification algorithms, this work aimed to construct an underwater image processing framework. Due to the special characteristic of underwater images,segment the image to several parts before directly perform a subject identification is thought an efficient way. And for obtaining a good underwater image segment result, the work to improve the quality of the image is necessary. Such work contains image enhancement, color correction and noise reduction, etc. The experiments demonstrate that the proposed methods produced visually pleasing results, and the numerical image quality assessment also proved the effectiveness of this proposal. The organization of this thesis is as follows.
Chapter 1 briefly reviews the characteristics and types of acoustic imaging and optical imaging technologies in ocean. The traditional underwater imaging models and the issues of recent underwater imaging systems are also introduced.
Chapter 2 describes a novel underwater image enhancement method. The transmission is estimated by the proposed dual-channel prior. Then a robust locally adaptive filter algorithm for enhancing underwater images is used. In addition, the
artificial light removal method is also proposed. Compared with the traditional methods, the proposed method obtains better images.
Chapter 3 presents a color correction method to recover the distorted image colors. In the experiments, the proposed method recovers the distorted colors in real-time. The color corrected images have a reasonable noise level in their dark regions, and the global contrast is also well improved.
Chapter 4 describes two methods for image segmentation. The first one is the automatic clustering Weighted Fuzzy C Means (WFCM) based segmentation method. It automatically obtains a reasonable clustering result for the underwater images with simple texture. The second method is fast Active Contour Model (ACM) based image segmentation method, which dramatically improves the calculation speed. Compare with the traditional methods, the processing speed is improved by over 10 times.
Chapter 5 presents the conclusions of this work, and points out some future researchdirections
遺伝子工学と生物化学的アプローチによるグリセロールを活用したバイオ燃料生産とバイオレメディエーション
No full text九州工業大学博士学位論文 学位記番号:生工博甲第232号 学位授与年月日:平成27年3月25日1. Introduction||2. Metabolic engineering of escherichia coli to enhance hydrogen production from glycerol||3. Identification of beneficial knockouts in escherichia coli for hydrogen production from glycerol||4. Waste activated sludge reduction and bio-fuels production from waste glycerol||5. General conclusions and future planGlycerol is the main byproduct from biodiesel production and expected to be a cheap feedstock for the production of useful substances. Furthermore, waste glycerol (WG) which is released from biodiesel production has a high pH level as well as contains toxic chemicals. Treatment of this waste requires a high cost, in turns raising cost to the biodiesel industry. Therefore, glycerol and WG should be either utilized or treated properly to make the biodiesel industry to be more competitive as well as to reduce the environmental burden. Here, in the framework of this thesis two approaches were taken: (1) Utilize glycerol as a feedstock for producing hydrogen via metabolic engineering in Escherichia coli; and (2) Bioremediation of WG and waste activated sludge (WAS) to produce biofuels (hydrogen and methane) and to reduce sludge.
E. coli is a potential microorganism for hydrogen production because it can sustain a high growth rate, requires simple technology and could achieve a high hydrogen yield and production. However, hydrogen production from glycerol by E. coli is still not effective because of slow cell growth and low hydrogen production. Thus, we aimed to enhance hydrogen production from glycerol by using E. coli which can be easily manipulated. We took to sub-approaches: (i) improvement of glycerol metabolism toward hydrogen production by metabolic engineering; and (ii) random transposon mutagenesis to find beneficial knockouts for hydrogen production. In the first approach, a novel engineered strain with seven knockouts, BW25113 frdC ldhA fdnG ppc narG mgsA hycA was constructed and it shows 5-fold higher hydrogen productivity (μmol H2/ mg protein) than the parent strain. In the other approach, four genes, aroM, gatZ, ycgR, and yfgI were found by transposon mutagenesis and these knockouts showed better growth rate and hydrogen production.
In the second approach, WAS which is released from the waste water treatment plant (WWTP), and is an environmental burden. Conventional treatment methods such as heating or dumping of WAS often require either high cost or large landfill, respectively. In practice, it is estimated that WAS treatment accounts for a half of the operating cost of the WWTP. By utilizing WAS as a microbial source to degrade glycerol and alkaline pH characteristic of WG to reduce WAS quantity, the anaerobic digestion was conduced with different WAS and WG ratios to figure out the optimal condition for sludge reduction and biofuel production. It is found that WAS was reduced by 62% under the condition of 25% WAS and 50% WG. Moreover, anaerobic digestion of 10% WAS and 1% WG was the optimal condition for producing hydrogen and methane. At this mode, hydrogen and methane production was increased by 24 and 8 fold in comparison to those of without supplementation of WG, respectively. Finally, codigestion of WAS and WG is economically viable for the WWTP, and this technique is more beneficial for the biodiesel fuels production manufactures
Sol-gel synthesis of magnetic TiO2 microspheres and characterization of their in vitro heating ability for hyperthermia treatment of cancer
Get PDFCommon cancer treatments are invasive and lack specificity, leading to unwanted side effects. Because hyperthermia can kill cancer cells and damage proteins and structures within cells, it has been considered a novel, minimally invasive cancer treatment. However, many hyperthermia treatments cannot heat deep-seated tumors effectively and locally. Heat-generating magnetic microspheres can help address this challenge. However, current research has not produced microspheres that can be sufficiently heated. We prepared magnetic titania (TiO2) microspheres by introducing magnetite nanoparticles (MNPs) into the sol–gel process during water-in-oil emulsion for in situ hyperthermia treatment of cancers. Two types of MNPs were used in this study: One type was synthesized by a chemical coprecipitation method, and the other type was commercially available MNPs. The obtained microspheres contained up to 46.7 wt% MNPs, and their saturation magnetization and coercive force were 34.2 emu/g and 103 Oe, respectively. The particles’ in vitro heating efficiency in an agar phantom was measured in an alternating magnetic field of 300 Oe and 100 kHz. The temperature increase in the agar phantom within 300 s was 4.5 °C for microspheres with MNPs that were synthesized by chemical coprecipitation and 53 °C for microspheres with commercially available MNPs. The excellent heating efficiency of the microspheres may be attributed to the hysteresis losses of the magnetic particles. These microspheres are believed to be promising thermoseeds for hyperthermic treatment of cancer
下水余剰汚泥の嫌気消化によるメタン生産と汚泥減量化を促進するための生物化学的アプローチ
Get PDF九州工業大学博士学位論文（要旨） 学位記番号:生工博甲第235号 学位授与年月日:平成27年3月25
Smart Power Supply System Which Utilized Lithium Ion Battery for Electric Vehicle
No full text九州工業大学博士学位論文 学位記番号:工博甲第404号 学位授与年月日:平成27年9月25日1 序論||2 リチウムイオン電池の原理||3 LIBの充放電サイクル||4 リチウムイオン電池電極の物性評価||5 リチウムイオン電池電極の機械特性評価法||6 電池寿命の予測||7 電池寿命改善における負極の役割||8 結
The Association between the Score and the Vocabulary in the Waka Essay by High School Student with Waka Learning System
Get PDFKnowledge-Based and Intelligent Information & Engineering Systems 19th Annual Conference, KES-2015, Singapore, September 2015 ProceedingsWe were allowed to examine the Waka essays (below: ’Kanshoubun’) of high school students studying language arts. The Kanshoubun is about understanding works of art. Waka is a Japanese fixed-form poem. We focused on the association between Kanshoubun scoring results and the vocabulary used in the Kanshoubun. We found that there is correlation between scoring results and the vocabulary used in the Kanshoubun, and also the students become to use more words by Wakaton, new learning method proposed by authors
Identify a Specified Fish species by the Co-occurrence and Confusion Matrix
Get PDFThe 3rd International Conference on Industrial Application Engineering 2015, March 28-31, 2015, Kitakyushu International Conference Center, Kitakyushu, JapanNowadays, invasive species threaten native species has become a global problem. Invasive species might be carrying pathogenic microorganisms, reduce biological species and even threat to human health. Therefore, in this study, we proposed a method of co-occurrence matrix to texture analysis of three species of fish. We catch the body pattern, and make a judgment based on confusion matrix. Simulation results show that three species of fish can be classified from each other reasonable