Near-field scanning optical microscopic transient lens for carrier dynamics study in InGaN/GaN

Time-resolved microscopic transient lens (TR-M-TL) and near-field scanning optical microscopic transient lens (NSOM-TL) were performed to reveal temporal and spatial behavior of carrier dynamics in InGaN/GaN quantum wells. The carrier and thermal dynamics were observed through the time profile of the TR-M-TL signal. Also, NSOM-photoluminescence and NSOM-TL images were observed at the same time. By comparing these two images, both radiative and nonradiative recombination centers in InGaN active layer were unambiguously discriminated with submicrometer scale. Such nonradiative carrier dynamics has been difficult to observe by conventional techniques in spite of its importance

Surface-plasmon enhanced bright emission from CdSe quantum-dot nanocrystals

We obtained very bright light emission from CdSe quantum dots (QDs) by using the surface-plasmon (SP) coupling technique. 23-fold enhanced photoluminescence (PL) intensities and two-fold increased PL decay rates are observed when the QDs are located on evaporated gold films. This enhancement is not effective for CdSe cores with ZnS shells (ZnS/CdSe). The reason for this difference can be explained by using the SP dispersion diagram and by considering the SP coupling mechanism. We discuss the inherent merits and demerits of this technique to increase the emission efficiency. This technique will enable high-speed and efficient light emission for optically as well as electrically pumped light emitters

Mask pattern transferred transient grating technique for molecular-dynamics study in solutions

We have developed a mask pattern transferred transient grating (MPT-TG) technique by using metal grating films. Transient thermal grating is generated by an ultraviolet light pattern transfer to nitrobenzene in 2-propanol solution, and the subsequent effect is detected through its diffraction to a probe beam. The thermal diffusion coefficient is obtained by the relationship between the grating periods and the signal decay lifetime, and is well in agreement with the calculated value. This technique has many advantages, such as a simple setting, an easy alignment, accurate phase control, and high stability for molecular-dynamics study in solutions

Rich Periphery, Poor Center: Myanmar's Rural Economy under Partial Transition to a Market Economy

This paper looks at the case of Myanmar in order to investigate the behavior and welfare of rural households in an economy under transition from a planned to a market system. Myanmar's case is particularly interesting because of the country's unique attempt to preserve a policy of intervention in land transactions and marketing institutions. A sample household survey that we conducted in 2001, covering more than 500 households in eight villages with diverse agro-ecological environments, revealed two paradoxes. First, income levels are higher in villages far from the center than in villages located in regions under the tight control of the central authorities. Second, farmers and villages that emphasize a paddy-based, irrigated cropping system have lower farming incomes than those that do not. The reason for these paradoxes are the distortions created by agricultural policies that restrict land use and the marketing of agricultural produce. Because of these distortions, the transition to a market economy in Myanmar since the late 1980s is only a partial one. The partial transition, which initially led to an increase in output and income from agriculture, revealed its limit in the survey period.

Agricultural Policies and Development of Myanmar\u27s Agricultural Sector: An Overview

This paper reviews the development of the agricultural sector in Myanmar after the transition to an open economy in 1988 and analyzes the nature as well as the performance of the agricultural sector. The avoidance of social unrest and the maintenance of control by the regime are identified as the two key factors that have determined the nature of agricultural policy after 1988. A major consequence of agricultural policy has been a clear difference in development paths among the major crops. Production of crops that had a potential for development showed sluggish growth due to policy constraints, whereas there has been a self-sustaining increase in the output of those crops that have fallen outside the remit of agricultural policy

Magnetization Plateaus in the Spin-1/2 Kagome Antiferromagnets: Volborthite and Vesignieite

The magnetization of two spin-1/2 kagome antiferromagnets, volborthite and vesignieite, has been measured in pulsed magnetic fields up to 68 T. A magnetization plateau is observed for each compound near the highest magnetic field. Magnetizations at saturation are approximately equal to 0.40Ms for both compounds, where Ms is the fully saturated magnetization, irrespective of a difference in the distortion of the kagome lattice between the two compounds. It should be noted that these values of magnetizations are significantly larger than Ms/3 predicted theoretically for the one-third magnetization plateau in the spin-1/2 kagome antiferromagnet. The excess magnetization over Ms/3 is nearly equal to the sum of the magnetizations gained at the second and third magnetization steps in volborthite, suggesting that there is a common origin for the excess magnetization and the magnetization steps.Comment: 4 pages, 4 figures. Phys. Rev. B, accepte

Near-field scanning optical microscopy of photonic crystal nanocavities

Near-field scanning optical microscopy was used to observe high-resolution images of confined modes and photonic bands of planar photonic crystal (PPC) nanocavities fabricated in active InGaAsP material. We have observed the smallest optical cavity modes, which are intentionally produced by fractional edge dislocation high-Q cavity designs. The size of the detected mode was roughly four by three lattice spacings. We have also observed extended dielectric-band modes of the bulk PPC surrounding the nanocavity by geometrically altering the bands in emission range and eliminating localized modes out of the emission range

食事画像からの自動カロリー量推定システムの実現

近年では, 健康的至高の高まりにより食事記録を付ける人が増えてきている. それに伴い食事記録支援システムが多く公開され始めているが, 既存のシステムのほとんどが正確にカロリー量を推定することができない. そこで本論文では食品を基準物体と撮影することで, 食品の認識を行い, さらに大きさを推定することでその食品のカロリー量を推定するシステムを提案する. システムはユーザーの携帯性や利便性を考えスマートフォンアプリという形での実装を行う. システムは画像中より食品領域及び基準物体領域を抽出し, その大きさを比較する. 基準物体は事前に面積がわかっていること以外には制約はなく, ユーザーが各々常に携帯しているものを使用することが出来る. 食品認識部分の手法には高精度な認識が可能なディープラーニングを用いた. 一般にディープラーニングによる画像認識は計算量が多くモバイルでの利用は難しいが, パラメータ数が少ないネットワークを選択したりなどの工夫により, サーバを介さずモバイル上での実行ながら約0.2 秒程度での実行速度で高精度な認識を可能にした. 実験ではカロリー量推定実験とユーザー評価実験の2 つを行い結果としてカロリー量推定実験での誤差の平均は52.231kcal, 相対誤差の平均は0.213 となった.ユーザー評価実験でも既存システムよりも記録を取りやすいという評価を得た. このことから提案システムの有効性が確認できた.電気通信大学201