山口大学工学部研究報告第56巻第2号目次


  1. InGaN系量子井戸LED構造の選択励起下における発光効率
    黒本径資, 角川健一, 山田陽一, 田口常正, 只友一行, 工藤広光, 岡川広明
    要旨】【本文(PDF)

  2. Optimal division of signal-coordinated arterial street into subareas
    Mamoru HISAI, Tsutomu USAMI
    要旨】【本文(PDF)

  3. 根系を含む表層土の透水性と強度特性
    鈴木素之, 山本哲朗, 枇杷雄介, 西村昌也
    要旨】【本文(PDF)

  4. せん断と圧密履歴を受けたセメント安定処理土の一軸圧縮強さ
    鈴木素之, 山本哲朗, 平岡真樹
    要旨】【本文(PDF)

  5. 生分解性樹脂の地盤材料特性
    鈴木素之, 山本哲朗, 長谷川秀人, 松本晶
    要旨】【本文(PDF)


要旨一覧

InGaN系量子井戸LED構造の選択励起下における発光効率
黒本径資, 角川健一, 山田陽一, 田口常正, 只友一行, 工藤広光,
岡川広明
要旨
Luminescence efficiency of InxGa1-xN-based light-emitting diodes (LEDs) has been studied by means of excitation-power-density- and temperature-dependent photoluminescence spectroscopy. The internal quantum efficiency (IQE) of LEDs was evaluated at various excitation photon energies using a wavelength-tunable dye laser system. The IQE obtained under selective excitation of InxGa1-xN active layers was approximately 1.5 times as high as that obtained under band-to-band excitation of GaN and AlGaN cladding layers.
本文(PDF)
Optimal division of signal-coordinated arterial street into subareas
Mamoru HISAI, Tsutomu USAMI
要旨
This study proposes a method for optimally dividing the signal-coordinated arterial street into subareas with different cycle length and describes the features of optimal division showing some examples of calculation.The optimal division into subareas and the optimal cycle length for each subarea are obtained by the DP technique.The optimal offsets for each subarea are also obtained by DP.Therefore,DP is applied two times.Among the three parameters of cycle length,split and offset,the splits are treated as given.A weighted sum of delay and stops is used as a performance index for optimization.Traffic conditions are assumed to be undersaturated and a platoon to be represented by a single rectangular wave.From some examples of calculation,the following has been made clear about optimal division into subareas: if there are no large differences in splits,road and traffic conditions among intersections,division into subareas should not be made.If there are differences in these condition,areas including signals with smaller splits or areas with heavier traffic should be controlled with a longer cycle length than those of the other areas,and the whole street should be divided into subareas according to link lengths and that arrangement.
本文(PDF)
根系を含む表層土の透水性と強度特性
鈴木素之, 山本哲朗, 枇杷雄介, 西村昌也
要旨
This paper describes permeability and shear strength characteristics of a surface soil containing tree roots. In this study, Tsukushihagi and Twine were used as tree roots and its alternatives, respectively. Tensile strength of tree roots was measured using a newly developed tension test apparatus. Also, falling head permeability and direct box shear tests were performed on specimen prepared with soil samples mixed with the tree roots or the alternatives. Main conclusions are as follows. 1) The tensile strength increased with an increase in diameter of tree roots. 2) The coefficient of permeability seems to be not changed by mass content of tree roots. 3) Whereas the internal fiction angle of soil containing tree roots is almost constant, the apparent cohesion increased with increasing the mass content of tree roots.
本文(PDF)
せん断と圧密履歴を受けたセメント安定処理土の一軸圧縮強さ
鈴木素之, 山本哲朗, 平岡真樹
要旨
A cement stabilized soil may be subjected to undrained shearing under an in-situ stress condition, so that a cementation is formed and destroyed simultaneously. Unconfined compression test was performed on a specimen in order to precompression in early curing period. Immediately after the precompressed specimen was cured under the atomosphere or an overburden pressure, the specimen was again compressed in unconfined compression test. Main conclusions are as follows. As curing time up to precompression became shorter, the unconfined compressive strength was increased. On the contrary, as the curing time became longer, the strength was decreased. When the overburden pressure was considerably high, a specimen subjected to any shear history caused a consolidation settlement and an increase of unconfined compressive strength. Anincrease rate of unconfined compressive strength of specimen with shear history was very low as compared to that without shear history.
本文(PDF)
生分解性樹脂の地盤材料特性
鈴木素之, 山本哲朗, 長谷川秀人, 松本晶
要旨
Construction wastes such as concrete and asphalt have been reduced, recycled and reused. On the other hand, wood waste has not been sufficiently recycled. Attempts to improve mechanical characteristics of the biodegradable plastic by mixing with the wood have been made in various fields. A granular material with biodegradability has already been developed in the process of producing gardening, dish plate, architecture material, etc. We are researching an applicability of the granular material for drainage layer in fill material. It is very important to develop a new geomaterial that have a long-term safety for environment. The granular material was buried under a clay ground and a degree of the biodegradation was measured. Mechanical behavior of the buried granular material was examined using unconfined and triaxial compression tests. As a result, the biodegradable ratio of the granular material is approximately 3% per a year. Furthermore, the internal friction angle of the granular material is almost constant, irrespective of the buried period.
本文(PDF)


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