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Electrorefining of aluminum scrap using aluminum chloride ionic liquids [an abstract of dissertation and a summary of dissertation review]
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熱容量を持つ大口径基礎杭利用地中熱交換器の設計・性能評価手法に関する研究
Get PDFIn today's world, the demand for energy is immense, leading to substantial annual energy consumption. The foremost environmental challenge facing humanity is global warming, largely attributed to the greenhouse effect caused by carbon dioxide (CO2) emissions. These significant CO2 emissions mainly stem from the extensive use of fossil fuels to meet diverse energy needs. Notably, building energy consumption represents about 40% of global energy usage, with heating and cooling in buildings accounting for 50%-60% of this figure. To substantially reduce greenhouse gas emissions, energy supplies for space cooling and heating must be shifted from fossil fuels to renewable energy sources. Ground Source Heat Pump (GSHP) systems are increasingly being adopted in residential and commercial buildings worldwide due to their remarkable energy efficiency, environmental benefits, consistent operation, and seamless integration with other energy systems. However, their widespread application is hindered by the need for large land areas for boreholes when installing multiple Ground Heat Exchangers (GHEs). Thermal piles, a novel type of vertical GHE, exhibit superior heat exchange capabilities because of their large diameter and high thermal capacity. Their primary advantage is the elimination of the need for additional land, as they are integrated directly beneath buildings. This dual functionality provides both structural support and efficient heat exchange. This doctoral thesis delves into the design and performance evaluation methods for large diameter, high capacity thermal piles, proposing optimal design strategies for their use in energy-efficient buildings. By combining theoretical innovation, empirical research, and practical implementation, this thesis positions itself as a valuable reference for future research and practical deployment in the field of thermal piles. Chapter 1 presents the background of the study, setting the stage and underscoring the significance of the research. It emphasizes the critical role of thermal piles, an innovative class of vertical GHEs noted for their effective heat exchange properties. The chapter outlines the research objectives, concentrating on devising novel methodologies for the design and performance evaluation of thermal piles. Chapter 2 offers a comprehensive literature review of the existing research on spiral tube GHEs and their integration into thermal piles. This chapter sets the foundation for the development of novel design and evaluation methods proposed in this thesis, aiming to bridge the identified research gaps. Chapter 3 introduces a novel computational approach for double spiral tube GHEs, designed to enhance the precision and efficiency of heat transfer calculation. This method employs the Capacity and Resistance Model (CaRM) approach, offering a comprehensive examination of the heat transfer dynamics in thermal piles. A key innovation is the integration of fin efficiency, which substantially streamlines heat transfer calculations for spiral pipes. The chapter also provides a detailed introduction to a Zero-Energy Building (ZEB) in Sapporo, which serves as the data collection site for method validation. This new calculation method has successfully integrated into the GroundClub and rigorously validated within a GSHP system for winter heating and summer cooling applications. Simulation results demonstrate a close correlation with actual measured data, characterized by a low Root Mean Squared Error (RMSE) and highly precise fluid temperature variations. The method's superiority in terms of precision and practicality is further underscored by a comparative analysis with another model employed in studying spiral tube GHEs. The comparison reveals that the application of fin efficiency for simplified heat transfer in this model results in more precise calculated outcomes. Chapter 4 provides an empirical analysis of the performance of double spiral tube GHEs in the ZEB, based on nearly two years of operational data. This chapter improves upon previous research by introducing a novel, comprehensive metric: the coefficient of heat extraction/injection, for a more precise evaluation of GHE performance. The chapter describes the methodology employed to calculate this metric, offering a more precise evaluation of GHE performance. The methodology for calculating this metric is detailed, with a focus on assessing the heat exchange capability of GHEs. An extensive analysis of the measurement data is carried out, employing linear regression and histograms for data simplification and clearer visualization. This method determines an efficiency rate for thermal piles with double spiral tube GHEs at approximately 4 W/m∙K, significantly higher than conventional U-tube GHEs. These results demonstrate the effectiveness of the new evaluation metric and affirm its practical applicability. Furthermore, the chapter assesses the performance of the GSHP system. This involves calculating the System Coefficient of Performance (SCOP), Seasonal COP, and the annual heat extraction/injection rates of GHEs using the gathered data. The study observes that climate warming, characterized by rising summer temperatures in colder regions, leads to an increased cooling demand, sometimes surpassing winter heating needs. This imbalance in heat extraction and injection causes fluctuations in underground temperatures, affecting heat pump efficiency. These findings emphasize the necessity of incorporating climatic considerations in the design and implementation of future GSHP systems. Chapter 5 combines the computational methods for double spiral tube GHE, introduced in Chapter 3 with the performance evaluation metrics for GHEs discussed in Chapter 4. It develops an optimal design approach for thermal piles used in GSHP systems. This approach enables rapid calculation of the ideal pitch length for double spiral tube GHEs and aids in determining the most cost-effective installation techniques for thermal piles. This chapter comprehensively explains the detailed calculation procedures of this optimized design method. Furthermore, the chapter includes simulations of this design methodology under a range of conditions, including daily operating hours, undisturbed ground temperature, underground soil conductivity, underground depth, and the diameter of thermal piles. These factors are crucial in the design of GSHP systems. The results reveal that the spiral length of double spiral GHEs has a significant impact on its thermal efficiency. Several variables markedly affect the optimization process, leading to considerable variations in optimal spiral length and total investment costs under different scenarios. Based on the simulation results, this chapter summarizes patterns in thermal pile design that could guide future projects. It offers practical insights and recommendations, thereby contributing to the effective deployment of thermal piles in energy-efficient buildings. Chapter 6 summarizes the key findings from the previous chapters, recognizing the limitations of the research and outlines potential directions for future studies. The chapter concludes by emphasizing the significance of the methodologies developed in evaluating the energy efficiency of thermal piles and their optimal design, offering both academic insights and practical solutions for GSHP systems
A Study of Mitochondria-Targeted Progression-Delaying Therapy for Duchenne Muscular Dystrophy in Skeletal and Cardiac Muscle
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Wang Chong's View of Imagery
No full text本論の目的は、『論衡』乱龍篇・遭虎篇・商蟲篇に見える土龍、虎、蟲の「意象」の特徴とそれらに付与された意味を解読した上で、王充の異なる「意象」に対する態度とその原因を分析し、さらに王充の「意象」観を明らかにすることである。従来の研究では、王充が、乱龍篇で初めて「意」と「象」を併用し、「意象」に「禮貴意象」（禮は意象を貴ぶ）といった定義をしたことを評価することがほとんどであった。しかし、王充は「意象」を判断する基準については十分に討論されたとは言い難い。本論はその点に着目し、王充は「意象」の判断基準として「禮」を用いており、また『論衡』の主旨である「疾虚妄」と関係があることを明らかにした。しかし、「禮」にこだわる王充は、虎・蟲という「意象」が持つ文学表現上の意義をあまり重要視していなかったことも同時に確認できた。このような王充の独特の「意象」観の由来と後世にどのような影響を与えたかについては、今後の課題としたい
F. S. Fitzgerald “My Lost City” and the Closed City of Haruki Murakami : The Reception of Fitzgerald as a City Novelist
No full text村上春樹を対象にした比較文学研究は盛んに行われているが、彼のアメリカ文学との関係を実証的に明らかにする作業は意外と進んでいない。フィッツジェラルドFrancis Scott Fitzgerald の受容が村上の文学の形成にとってとりわけ重要であることは周知の通りであるが、本格的な研究は少なかった。本論は村上の独自のフィッツジェラルド受容のあり方を明らかにする。そのために「フィッツジェラルド体験」（『マイ・ロスト・シティー』中央公論社、一九八一年五月）、「都市小説の成立と展開─ チャンドラーとチャンドラー以降」（『海』中央公論社、一九八二年五月）を中心とした村上の発言と、村上の最初の翻訳集の表題に採用されたフィッツジェラルドのエッセイ「マイ・ロスト・シティー」“My Lost City”（『マイ・ロスト・シティー』）を検討する。その上で『風の歌を聴け』（講談社、一九七九年八月）、「中国行きのスロウ・ボート」（『中国行きのスロウ・ボート』中央公論社、一九八三年五月）といった初期小説の形成におけるフィッツジェラルド受容の関与を測定する。村上はフィッツジェラルドを都市とモラルを対立させながら華やかな都市風俗を描いた都市小説作家であると見なしている。都市生活に主体性を制限されながらも、救済を信じて小説を書き続けるモラリスティックな姿勢を村上は評価する。この姿勢に加えて、都市の精神的な閉塞性を空間的な限定性になぞらえて語る「マイ・ロスト・シティー」を受容して、村上は初期小説において、書くことの不可能性をもたらす閉塞的空間として都市を表わし、その中で救済を信じ小説を書こうとする小説家の主人公を設定するのである。作品を通して感受された作家の姿勢を小説の構成へと変換する、一種の〈翻訳〉の手法が認められる
