Simultaneous velocity measurement of water and bubble flows in breaking waves

Proceedings of the Seventh International Conference on Hydroscience and Engineering, Philadelphia, PA, September 2006. http://hdl.handle.net/1860/732Breaking waves produce numbers of vortices through a jet splashing process and also entrain many air bubbles, forming complicated air-water two-phase turbulent flow field in a surf zone. In this research, a simultaneous velocity measurement technique of water and bubble flows in breaking waves is developed for characterizing water-bubble interactions within vortices in a surf zone. The bubbles and neutral buoyant tracers are separately recorded by two different digital video cameras on the basis of an optical filtering technique. It is found that bubble motion does not follow water flow in a vortex, and mean bubble velocity is always higher than water velocity in breaking waves. Bubble-induced turbulent energy is estimated to be less than 10 % of total turbulent energy

Rational Choice Hypothesis as X-point of Utility Function and Norm Function

Towards the realization of a sustainable, fair and inclusive society, we proposed a novel decision-making model that incorporates social norms in a rational choice model from the standpoints of deontology and utilitarianism. We proposed a hypothesis that interprets choice of action as the X-point for individual utility function that increases with actions and social norm function that decreases with actions. This hypothesis is based on humans psychologically balancing the value of utility and norms in selecting actions. Using the hypothesis and approximation, we were able to isolate and infer utility function and norm function from real-world measurement data of actions on environmental conditions and elucidate the interaction between the both functions that led from current status to target actions. As examples of collective data that aggregate decision-making of individuals, we looked at the changes in power usage before and after the Great East Japan Earthquake and the correlation between national GDP and CO2 emission in different countries. The first example showed that the perceived benefits of power (i.e., utility of power usage) was stronger than the power usage restrictions imposed by norms after the earthquake, contrary to our expectation. The second example showed that a reduction of CO2 emission in each country was not related to utility derived from GDP but to norms related to CO2 emission. Going forward, we will apply this new X-point model to actual social practices involving normative problems, and design the approaches for the diagnosis, prognosis and intervention of social systems by IT systems.Comment: 15 pages, 13 figures. Published online at http://redfame.com/journal/index.php/aef/article/view/4890 . Related to arXiv:2002.0903

Sustainability and Fairness Simulations Based on Decision-Making Model of Utility Function and Norm Function

We introduced a decision-making model based on value functions that included individualistic utility function and socio-constructivistic norm function and proposed a norm-fostering process that recursively updates norm function through mutual recognition between the self and others. As an example, we looked at the resource-sharing problem typical of economic activities and assumed the distribution of individual actions to define the (1) norm function fostered through mutual comparison of value/action ratio based on the equity theory (progressive tax-like), (2) norm function proportional to resource utilization (proportional tax-like) and (3) fixed norm function independent of resource utilization (fixed tax-like). By carrying out numerical simulation, we showed that the progressive tax-like norm function (i) does not increase disparity for the distribution of the actions, unlike the other norm functions, and (ii) has high resource productivity and low Gini coefficient. Therefore the progressive tax-like norm function has the highest sustainability and fairness

Technetium-99m Methoxyisobutyl Isonitrile Scintigraphy of Bone Metastasis in Three Patients with Differentiated Thyroid Cancer

We studied the usefulness of ^Tc-methoxyisobutyl isonitrile (MIBI) scintigraphy in the detection of bone metastases and in evaluation of therapeutical response to ^I-Na in three patients with differentiated thyroid cancer. On ^Tc-MIBI scintigraphy, increased accumulations were observed in all bone metastatic lesions (14 lesions), whereas on bone scintigraphy using ^Tc-hydroxymethylene diphosphonate (^Tc-HMDP) both increased (eight lesions, 57%) and decreased (six lesions, 43%) accumulations were observed. Within two months after ^I-Na treatment, all 14 lesions were unchanged on bone scintigraphy. However, on ^Tc-MIJBI scintigraphy, disappearance of uptake (six lesions, 43%) and decreased uptake (seven lesions, 50%) were observed in 13/14 lesions (93%). Therefore, ^Tc-MIBI scintigraphy was useful not only in the detection of bone metastatic lesions but also in evaluation of the therapeutical response to ^I-Na in differentiated thyroid cancer

A Study of Cases with Rib Metastasis Difficult to Distinguish from Microfractures on Bone Scintigraphy

A retrospective study of about 10,000 cases at Kawasaki Medical School Hospital on whom bone scans were performed over a six year period revealed five cases in which metastasis was mistaken for a benign rib lesion. This mistake occurred because the accumulation pattern of the radionuclide in the rib region on the bone scan indicated a so-called "hot spot" observed with microfractures rather than the rod-like increased accumulation along costal bones that is coincident with the finding of bone metastasis. This experience suggests that solitary hot spots in the rib region on bone scans should be diagnosed carefully, as such an accumulation is most frequently associated with a benign etiology but rarely may be a malignant lesion

プールの健康教室に参加することによる心身への影響―低身体活動高齢女性の実態調査―

目的：群馬県内のAプールが実施している健康教室に参加することが心身に及ぼす影響を明らかにすることを目的とした． 方法：研究参加に同意した65歳以上の低身体活動の女性11名を対象者とした．教室参加前に年齢，健康状態，気分を，教室当日に運動前，中，後の血圧・脈拍，主観的運動強度を，教室終了後に気分を調査した．任意で体力測定を行った． 結果：体力測定の結果は，握力，上体起こし，長座体前屈，開眼片足立ち，10m障害物歩行の全てで全国平均よりも低かった．気分は，教室参加後に緊張・不安が有意に低下した．収縮期血圧は運動後では運動前よりも有意に上昇し，脈拍は運動前よりも有意に低下した．主観的運動強度は運動前よりも有意に上昇した． 結論：対象者は，肥満，筋力低下傾向にあるが，集団で実施する水中運動の強度は適度であった．健康教室により，緊張・不安が改善し，適度な運動強度においても血圧や脈拍の有意な変動が認められた．Objectives: The purpose of this study was to investigate the effects of a health class offered at a swimming pool. Methods: The subjects were 11 women aged 65 years or older who had low active mass. We investigated age, health condition, and mood before the health class. On the day of the health class, we measured blood pressure, pulse, and perceived exertion before, during, and after aquatic exercise. We then investigated mood after the health class. We also offered an optional physical fitness test to the subjects. Results: Scores for grip strength, sit-ups, toe touching, one-leg standing with eyes open, and 10-m obstacle walking test results were below healthy levels. The mood test showed that tension and anxiety were improved. Systolic blood pressure was significantly higher, pulse was significantly lower, and the rate of perceived exertion was significantly higher after exercise than before. Conclusions: The subjects were obese and had muscle weakness, but the exercise was of moderate intensity. Tension and anxiety improved after the health class. Significant changes in blood pressure and pulse were found after exercise.原

現地観測に基づく水温躍層の破壊と鉛直混合に関する研究

金沢大学理工研究域環境デザイン学系This study focuses on the process of thermocline\u27s destruction and reformation during typhoons using field observation data. The thermocline has a large effect on the circulation and would be a factor to make water worse. Therefore, it is necessary to understand its process deeply. In this study, the stability of density stratification was evaluated based on the Brant-Vaisala frequency and the Richardson number. The results suggested that high wave destroyed the stratification and high wind mixed ocean water vertically more energetically during stratified season. On the other hand, is was found that stratification was unstable regardless of typhoon intensity during unstratified season. Moreover, the characteristics of water-mass were evaluated on the TS diagram during unstratified season.台風イベント時の水温躍層の破壊・再形成のプロセスに着目して，観測データの解析を行うことでプロセスの経過について検討した．水温躍層は水域内の流動に大きな影響を与え，水質問題が生じる要因にもなるため，詳細な現象の把握が求められている．そこで本研究では，台風イベント時の観測データからブラント・バイサラ振動数およびリチャードソン数を算出し，成層の安定性を評価した．その結果，密度成層期には，まず高波浪により成層の安定が崩され強風により更に不安定さが促進されるという仮説を得た．また，混合期は成層が不安定で，台風接近前からシア流の不安定が生じていて混合が生じていることがわかった．これらの結果を踏まえて，更にTS図を作成し混合期の水塊の特性を評価した.出版者照会後に全文公