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In this study, the transient three-dimensional numerical simulations based on the MARS (Multi-interface Advection and Reconstruction Solver) with the non-empirical boiling and condensation model have been conducted for isolated boiling bubble behaviour in a subcooled pool. The effects of the wettability on the heating surface for the subcooled bubble departure behaviour were investigated. The numerical results showed in very good agreement with the experimental results. Furthermore, resulting from the wall heat flux evaluation, it was found that the wall heat flux near the contact line at the bottom of the bubble just before the bubble departing from the heating surface increases with increases of the degree of subcooling.

This study focused on a bubble rising behavior in a molten glass because it is important to improve the efficiency of removal of bubbles from the molten glass. On the other hand, it is expected that some gas species which exists in a bubble are transferred into the molten glass through the bubble interface, i.e., the mass transfer, subsequently, it may cause a bubble contraction in the molten glass. In this paper, in order to understand the bubble rising behavior with its contraction caused by the mass transfer through the bubble interface in the very high viscous fluid such as the molten glass, a bubble contraction model has been developed. The direct numerical simulations based on the MARS (Multi-interface Advection and Reconstruction Solver) coupled with the mass transfer equation and the bubble contraction model regarding the mass transfer from the rising bubble in very high viscous fluid have been performed. Here, the working fluids were water vapor as the gas species and the molten glass as the very high viscous fluid. Also, the jump conditions at the bubble interface for the mass transfer were examined. Furthermore, the influence of the bubble contraction for the bubble rising compared to that in the water as a normal viscous fluid was investigated. From the result of the numerical simulations, it was found that the bubble rising behavior was strongly affected not only by the viscosity of the working fluid but also by the bubble contraction due to the mass transfer through the bubble interface.

The mechanism of bubble coalescence/repulsion is still unclear and is a key issue when it comes to numerical research on multiphase flows. Experimental studies have revealed that not only the concentration of the electrolytes dissolved in water but also the existence of ion pairs play an important role in bubble coalescence, which indicates that the contamination at the interface has an important effect on bubble interaction. In the present study, a coalescence model is developed; it is based on the conventional nucleation theory correlated with the electric conductivity originating due to the contamination of the liquid. Simple microbubble interactions are simulated using the coalescence model. Finally, we succeed in simulating the duration of contact before the coalescence of two microbubbles.

Bubble removal in viscoelastic solution is an important challenge in both industry production and laboratory experiments. However, no effective physical bubble removal technique in viscoelastic solutions has been reported until now. In this study, the ultrasonic vibration effect on bubble removal in viscoelastic solution (300ppm-CTAC/300ppm-NaSal viscoelastic solution) was firstly observed. The ultrasonic vibration can successfully remove bubbles whose diameter is ranging from 200 μm to 1mm, and from 300ppm CTAC/NaSal at 28°C through assembling bubbles to be a large size bubble cluster in our experiments. The detailed bubble-assembling process were observed and analyzed. It is pointed out that the bubble-assembling process was directly associated with the intensity of ultrasonic vibration and the distance between bubbles in the solutions. However, the detail mechanism of the bubble-assembling behavior is still unclear, which is worth of further observation.

In this study, in order to clarify the heat transfer characteristics of the subcooled boiling phenomena and to discuss on their mechanism, a non-empirical boiling and condensation model for numerical simulation has been adopted. This model consists of an improved phase-change model and a consideration of a relaxation time based on the quasithermal equilibrium hypothesis. The transient three-dimensional numerical simulations based on the MARS (Multiinterface Advection and Reconstruction Solver) with the non-empirical boiling and condensation model have been conducted for an isolated boiling bubble behavior in a subcooled pool. The subcooled bubble behaviors, such as the growth process of the nucleate bubble on the heating surface, the condensation process and the extinction behaviors after departing from the heating surface were investigated, respectively. In this paper, the bubble departing behavior from the heating surface was discussed in detail. The overall numerical results showed in very good agreement with the experimental results.

The liquid-column break problem is one of the well-known validation tests for the multiphase flow computations. However, a few experimental data are available until now regarding the liquid-column break problem. In the validation process, it is necessary to consider the differences of the boundary and initial conditions between both experiment and numerical simulation. In this study, we conducted the liquid-column break experiments and measured the position of the water-front and the gravity center of the water region by using a high-speed camera and an image analyzing software. These experimental results were compared with the numerical simulation results. The water front position is usually taken as a scaling measure to evaluate the accuracy of numerical method for multiphase flows. However, when the real sizes of the liquid column changed to double without changing the aspect ratio (height/width), the non-dimensional water front positions were changed. From this fact, it is considered that the position...

At a gas‐liquid interface, there are many physics and unknown phenomena related to thermodynamics, electromagnetics, hydrodynamics, and heat and mass transfer. Therefore, a modeling of gas‐liquid interface is one of key issues of the numerical research on multiphase flow. In this study, assuming that the interface is a thin fluid‐membrane and has a finite thickness, we develop a new gas‐liquid interfacial model based on thermodynamics (Phase Field theory) via mathematical approach. In particular, we derive the equation of free energy based on the lattice gas model. In the derivation, the effect of the electric double layer caused by a contamination at the interface is considered. Moreover, we consider the importance of the contamination from the perspective of our experiment: microbubbly flow. In general, it is believed that the microbubble is hard to coalesce with each other unlike bubbles of millimeter size. However, we found lots of microbubble coalescence in the microbubbly flow. In the experiment, we report new findings regarding the microbubble coalescence by using a high speed camera, and try to elucidate the mechanism of the microbubble coalescence. Through our experiment and interfacial modeling, we consider the possible mechanism of bubble coalescence.

In this paper, the numerical simulations based on the MARS (Multi-interface Advection and Reconstruction Solver) with a phase-change model including the bubble growth and the condensation processes are performed. As the results, it was found that the numerical results for both bubble growth and condensation rates were very slow compared with the experimental results and the existing analytical model. In order to solve this discrepancy, the original model is improved by introducing the following models based on the quasi-thermal equilibrium state: (1) the improved phase-change model including the large density change between water and vapor; (2) a relaxation time model derived by considering the unsteady heat conduction. Resulting from the numerical simulation with the present improved model, the numerical results in both bubble growth and condensation processes show in good agreement with the experimental results and the existing analytical model.

When a loss of vacuum accident (LOVA) would occur in a nuclear fusion experimental reactor, a buoyancy-driven exchange flow takes place through breaches of a vacuum vessel. To concern the safety analysis, experiments were carried out to examine the effects of the enclosure configuration and the breach arrangement on the exchange flow rate at the vertical and/or horizontal breaches in an annular enclosure. Comparing the experimental results with the existing correlations of the exchange flow rate, the correlation based on the Bernoulli equation was found to provide the conservative results for small breaches in aspect of the release of radioactive materials from the vacuum vessel.

The electron-gamma shower code EGS4 was applied to the simulation of energy deposition from runaway electrons in the plasma facing components of tokamaks. We calculated the energy deposition in the...

Experimental study of turbulent flow in circular pipe is carried out by using PIV technique as a preliminary experiment for studying thermo fluid properties of molten salt, Flibe in particular, which is a high Prandtl number fluid. At this first stage, water is used as working fluid to obtain reference data. Measurements of the fully developed turbulent flow in a circular pipe at Re = 5286 are carried out using PIV system and near wall flow structure and turbulent statistics as well as averaged flow field are obtained. Average velocity profile has good agreement with the DNS data.

A high performance 0.15-/spl mu/m CMOS logic device has been developed with full-0.56 /spl mu/m pitch 3-level copper (Cu) interconnects. The multi-level interconnect system consists of Cu single-damascene wiring in combination with a borderless W plug at a high aspect ratio of 3.0. A two-step Cu CMP method suppresses new wiring failures which are Cu ball generated from Cu polishing dross and side wall damage. A Cu spike into the W plug is prevented by optimizing the W plug formation process. The 0.28-/spl mu/m wide Cu wiring with a borderless W plug has advantages over Al-Cu wiring for electromigration (EM) reliability. We achieve a 23% reduction of RC delay of a ring oscillator with a loaded wiring length of 1.5 mm by reducing the wiring thickness by 300 nm.

The ultimate goal of the study is the improvement of predictive methods for safety analyses and design of advanced reactors for higher efficiency and enhanced safety and for deployable reactors for electrical power generation, process heat utilization and hydrogen generation. While key applications would be advanced gas-cooled reactors (AGCRs) using the closed Brayton cycle (CBC) for higher efficiency (such as the proposed Gas Turbine - Modular Helium Reactor (GT-MHR) of General Atomics [Neylan and Simon, 1996]), results of the proposed research should also be valuable in reactor systems with supercritical flow or superheated vapors, e.g., steam. Higher efficiency leads to lower cost/kwh and reduces life-cycle impacts of radioactive waste (by reducing waters/kwh). The outcome will also be useful for some space power and propulsion concepts and for some fusion reactor concepts as side benefits, but they are not the thrusts of the investigation. The objective of the project is to provide fundamental thermal fluid physics knowledge and measurements necessary for the development of the improved methods for the applications.

This paper summarizes process, status and some examples of validation and verification (V and V) of the codes that are being used in ITER safety analyses. V and V information is provided for the codes involved in accident analyses dealing with water coolant ingress into the vacuum vessel and loss of vacuum.

We have been developing two computer codes in order to evaluate non-equilibrium thermophysical characteristics of the vapor from the plasma-facing materials (PFMs). One of these codes is a finite difference code for solving the three-dimensional Boltzmann-Krook-Welander [3D-BKW] equations that assume the material vapor phase as a fluid, and the other is a three-dimensional direct simulation Monte Carlo [3D-DSMC] code. Some numerical results by using the 3D-BKW code for the vapor temperature and density distributions of the PFMs at high temperature are compared with the results by using the 3D-DSMC code.

Two experimental studies for the thermal-hydraulic safety of fusion reactors, ingress of the coolant events (ICE) and loss of vacuum events (LOVA), have been started as ITER safety sub-tasks for three years since February, 1995. In these researches, as for the ICE experiments, the preliminary ICE apparatus has been completed by the end of September, 1995. On the other hand, as for the LOVA experiments, the preliminary LOVA apparatus that simulated a vacuum vessel of the fusion reactor with a small-scaled model has already been constructed. The buoyancy-driven exchange flow behavior through breaches between the inside (filled with helium gas) and the outside (i.e., air) of the apparatus under the LOVA condition was investigated quantitatively. This paper summarizes the outline of the preliminary ICE and LOVA apparatuses, their experimental contents and research schedules.

Using a preliminary LOVA apparatus which simulated a vacuum vessel of the fusion reactor with a small-scaled model, the buoyancy-driven exchange flow behavior through breaches between the inside (filled with helium gas) and the outside (air)of the vacuum vessel was investigated quantitatively under atmospheric temperature condition. The present experimental results clarified that the exchange flow rate was independent of the breach locations in the vacuum vessel and depended on strongly the magnitude of the potential energy from the ground level. In a single breach case, the exchange flow receives the effect of a counter-current flow through the breach. On the other hand, in a double breach case, since a one-through now path between two breaches is produced, the exchange flow rate is much larger than that of the single breach case.

In the present study, Direct Numerical Simulation (DNS) of the free-surface turbulent flow with constant temperature at the surface is performed. Numerical investigations are carried out for two Prandtl numbers 1.0 and 5.0 with the neutral or stable stratification (Ri=27.6), while a Reynolds number of 200, based on the friction velocity and flow depth. As the results, fundamental turbulent statistic data for the influence of Prandtl number change and buoyancy effect are obtained.

We have been performing PDT using Excimer Dye Laser (EDL) or YAG-OPO laser, a type of low power laser, both of which have a considerably higher degree of tissue penetration even when compared to PDT using Argon Dye Laser (ADL).PDT is a relatively simple procedure without any bleeding and does not require anesthesia since it causes no pain. PDT is performed 48 h after intravenous injection of 1.5–2.0 mg/kg of PHE (Photofrin®). Precise spot irradiation is possible using a colposcope with an optical laser path. We also use a cervical probe which enables photoirradiation of the entire cervical canal.We have performed PDT on 131 cases (95 CIS, 31 dysplasia, 1 vulval dysplasia (VIN), 3 squamous cell carcinoma, microinvasion, and 1 CIS + endocervical adenocarcinoma, microinvasion). Of these cases, 127 became CR (96.9%). The first CR case was 10 years ago and no recurrence has been observed yet.PDT is extremely effective to preserve fertility. Except for sensitive reactions to sunlight, there are no noticeable side effects or difficulties related to pregnancy or delivery. We expect that in the near future PDT will be performed using diode lasers and without hospitalization due to new photosensitizers which have shorter retention times.

One of the most important clinical issues in cancer chemotherapy is the presence of intrinsic resistance or the appearance of acquired resistance against chemotherapy. As for intrinsic resistance, we had to perform direct chemo-sensitivity testing, or had to rely on the knowledge empirically acquired from randomized clinical trials. However, molecular or genetic markers associated with chemo-sensitivity have been reported recently. For example, inactivation of p53 or GML gene has been reported to be associated with chemo-resistance. Overexpression of topo-isomerase I has been reported to be associated with chemo-sensitivity to Topo I inhibitor. Overexpression of Thymidine Phosphorylase has been found to be associated with chemo-sensitivity to prodrug of 5-FU. By checking the status of such chemo-sensitivity markers prior to chemotherapy, it would be possible to predict the chemotherapeutic effect and even the necessity of the chemotherapy in the near future. In this article, we review the chemo-sensitivity markers reported so far, and methodology contributing to the discovery of new chemo-sensitivity markers. As a clinical study, 11 cases of ovarian cancer with high sensitivity to cisplatin-based chemotherapy and 29 cases of ovarian cancer with chemoresistance were analyzed by Comparative Genomic Hybridization (CGH). Copy number decrease in Xp, and copy number increase in 19q were observed in 13, 12 out of 29 resistant cases (45, 41%) and zero, 1 out of 11 sensitive cases (0, 9%), suggesting that -Xp and +19q were likely to be a genetic event associated with intrinsic drug-resistance (p = 0.006, 0.05, respectively). This effort should contribute to the discovery of new chemo-sensitivity and resistance markers.

In 33 patients with primary ovarian cancer who had not received any chemotherapy before surgery, expression of glutathione S-transferase pi (GST-pi) was studied immunohistochemically in relation to the response to chemotherapy with CDDP, and furthermore it was examined whether numerical aberration of chromosome 11 was available as a prognostic indicator. The obtained results were as follows: 1. Of 33 ovarian cancer tissue samples, 19 (57.6%) showed positive staining and 14 (42.4%) negative staining for GST-pi. 2. The 5 year survival rate of the patients with GST-pi positive tumors was significantly lower than that of those with GST-pi negative tumors (p0.01). 3. The frequency of detection of cells showing numerical aberration of chromosome 11 in tissues was significantly higher in ovarian cancers than in benign ovarian tumors and normal ovaries. 4. The 5 year survival rate of the patients with ovarian cancer in which the cells showing numerical aberration of chromosome 11 at 20% or more was significantly lower than that of those in which such cells were under 20% (p0.02). These results show that expression of GST-pi and numerical aberration of chromosome 11 in the tissues of human ovarian cancers are useful as prognostic indicators.

The MARS (Multi-interfaces Advection and Reconstruction Solver) [1] is one of the surface volume tracking methods for multi-phase flows. Nowadays, the performance of GPU (Graphics Processing Unit) is much higher than the CPU (Central Processing Unit). In this study, the GPU was applied to the MARS in order to accelerate the computation of multi-phase flows (GPU-MARS), and the performance of the GPU-MARS was discussed. From the performance of the interface tracking method for the analyses of one-directional advection problem, it is found that the computing time of GPU(single GTX280) was around 4 times faster than that of the CPU (Xeon 5040, 4 threads parallelized). From the performance of Poisson Solver by using the algorithm developed in this study, it is found that the performance of the GPU showed around 30 times faster than that of the CPU. Finally, it is confirmed that the GPU showed the large acceleration of the fluid flow computation (GPU-MARS) compared to the CPU. However, it is also found that the double-precision computation of the GPU must perform with very high precision.

Technology and population rely on each other for sustenance and growth. Technology has helped produce more food, provide better health care, better communication, faster modes of travel, better consumer durables, greater amenities, and increased the quality of life for millions of people. There has been a price in terms of the widening gap between the technology of the developed and developing countries. There has also been rapid population growth that has resulted in a host of ills. Further, technology itself has produced toxic wastes and consumed a large amount of natural resources. This situation is easily seen as a dilemma between the limitless promises of technology and the limited resources created by large populations. The solution to the dilemma is sustainable development, a concept often talked about but seldom realized. The 90s will be a crucial decade for sustainable development as population is growing by 90 million/annum. 90% of the increase is occurring in developing countries. Within each country there is a trend towards urbanization. By 2000, 75% of Latin Americans, 42% of Africans, and 37% of Asians will live in urban environments. By 2050 there should be 100s of millions of migrants running from the slowly rising sea. The survival equation is sustainability S equals resources R time ingenuity 1 over population P. This is a conceptual equation, but it does illustrate that the impact of human ingenuity is just as important as resources. World commitment must come before any meaningful change will occur. The almost universal acceptance of human rights and fundamental freedoms exceeds the will to change in decision makers and expert consultants.

The CAD/CAM system has been established mainly in the field of automotive body sheet metal engineering. The system is a combination of large host mainframes, interactive graphics, on-line plotters and NC machines. The realized CAD/CAM system fulfills the following: (1) The automotive body surfaces are defined by a complete mathematical model. Original data of the model is taken from a clay model. As the result, press tools can be made quickly and precisely using NC techniques. (2) Drawings of body sheet metal are originated on the graphics computer. This data is available to other engineers, such as structural analysts and NC part programmers. (3) In addition, this system is the best tool for helping engineers examine wiping area of windshield, movement of side glass, volume of fuel tank, validity of wiring diagram and so on. This paper covers the key elements of CAD/CAM at Nissan Motor Company.

In 1985, there were approximately 427 million persons aged 60 and over in the world, accounting for about 9% of the world's population. By 2020, the elderly population will comprise 13% of the world's population and 70% of these people will live in developing countries. Governments and international agencies should increase their efforts and activities to improve care for the elderly within the family unit. The socioeconomic implications of aging are greater for females because of their higher life expectancy. In the year 2000, 11% of the world's female population will be aged 60 and over. By 2025, there will be 604 million elderly women in the world, 70% of whom will be living in developing countries, and among them, 70% in rural areas. An important issue requiring both research and policy attention is the interdependence among women's economic, health, and social concerns, which increase with age. The author calls for more specific policies that aim to eliminate discrimination against disabled persons, the elderly, and particularly elderly women. The author urges governmental and nongovernmental organizations to implement these recommendations: 1) promote research studies and the collection and analysis of information on the socioeconomic, health, legal, and demographic situation of elderly women; 2) promote awareness of elderly women's contribution to society; 3) eliminate discriminatory treatment of elderly women; 4) develop health promotion programs and services to meet elderly women's long-term care needs; 5) promote wider appreciation of continued participation of elderly women in social and cultural activities; 6) promote the development of elderly women's organizations and self-help groups; 7) promote and assure the participation of elderly women in the process of development; and 8) develop literacy programs and training programs for elderly women.

Liquid Phase hydrogenolysis of Thiophene by decaline with metals and metal sulfides on active carbon at 330–390°C, 0–11 kg/cm2 H2 clarified that Mo/A.C. or Co/A.C. was quite active as the catalyst and that hydrogen atoms in decaline transfered first to carbon surface, then moved on its surface to reach metal sulfide surface then to react with thiophene.

Die Pyrolyse von 3,4-Dichlor-1-buten (I) wird bei 350-500°C in Gegenwart von Stickstoff durchgefuhrt.