Measuring the social value of nuclear energy using contingent valuation methodology

As one of the promising energy sources for the next few decades, nuclear energy receives more attention than before as environmental issues become more important and the supply of fossil fuels becomes unstable. One of the reasons for this attention is based on the rapid innovation of nuclear technology which solves many of its technological constraints and safety issues. However, regardless of these rapid innovations, social acceptance for nuclear energy has been relatively low and unchanged. Consequently, the social perception has often been an obstacle to the development and execution of nuclear policy requiring enormous subsidies which are not based on the social value of nuclear energy. Therefore, in this study, we estimate the social value of nuclear energy-consumers’ willingness-to-pay for nuclear energy—using the Contingent Valuation Method (CVM) and suggest that the social value of nuclear energy increases approximately 68.5% with the provision of adequate information about nuclear energy to the public. Consequently, we suggest that the social acceptance management in nuclear policy development is important along with nuclear technology innovation

Direct observation of a liquid film under a vapor environment in a pool boiling using a nanofluid

The existence of a liquid film separating a vapor bubble from a heated solid surface is confirmed using a nanofluid. The existence of such a liquid film had been a theoretical premise of the critical heat flux mechanism, significantly difficult to verify through experimental observations. Here, we show that a liquid film under a massive vapor bubble adheres to a heated solid surface. The liquid film comes into being trapped in a dynamic coalescence environment of nucleate bubbles, which grow and depart continuously from the heated surface. In its dryout process, the liquid film displays vapor "holes" originating from the rupture of discrete nucleating bubbles. The dryout process of the liquid film can be understood from the vaporization of rims of the holes and of smooth film region.open51

Enhancement of paclitaxel-induced breast cancer cell death via the glycogen synthase kinase-3 beta-mediated B-cell lymphoma 2 regulation

Glycogen synthase kinase-3 beta (GSK-3 beta) is a serine/threonine protein kinase that is known to mediate cancer cell death. Here, we show that B-cell lymphoma 2 (Bcl-2), an anti-apoptotic protein, is regulated by GSK-3 beta and that GSK-3 beta-mediated regulation of Bcl-2 is crucial for mitochondrial-dependent cell death in paclitaxel-stimulated cells. We demonstrate that MCF7 GSK3 beta siRNA cells are more sensitive to cell death than MCF7 GFP control cells and that in the absence of GSK-3 beta, Bcl-2 levels are reduced, a result enhanced by paclitaxel. Paclitaxel-induced JNK (c-Jun N-terminal kinase) activation is critical for Bcl-2 modulation. In the absence of GSK-3 beta, Bcl-2 was unstable in an ubiquitination-dependent manner in both basal-and paclitaxel-treated cells. Furthermore, we demonstrate that GSK-3 beta-mediated regulation of Bcl-2 influences cytochrome C release and mitochondrial membrane potential. Taken together, our data suggest that GSK-3 beta-dependent regulation of Bcl-2 is crucial for mitochondria-dependent cell death in paclitaxel-mediated breast cancer therapy.clos

The analysis of security cost for different energy sources

Global concerns for the security of energy have steadily been on the increase and are expected to become a major issue over the next few decades. Urgent policy response is thus essential. However, little attempt has been made at defining both energy security and energy metrics. In this study, we provide such metrics and apply them to four major energy sources in the Korean electricity market: coal, oil, liquefied natural gas, and nuclear. In our approach, we measure the cost of energy security in terms of supply disruption and price volatility, and we consider the degree of concentration in energy supply and demand using the Hirschman-Herfindahl index (HHI). Due to its balanced fuel supply and demand, relatively stable price, and high abundance, we find nuclear energy to be the most competitive energy source in terms of energy security in the Korean electricity market. LNG, on the other hand, was found to have the highest cost in term of energy security due to its high concentration in supply and demand, and its high price volatility. In addition, in terms of cost, we find that economic security dominates supply security, and as such, it is the main factor in the total security cost. Within the confines of concern for global energy security, our study both broadens our understanding of energy security and enables a strategic approach in the portfolio management of energy consumption.Energy security cost Hirschman-Herfindahl index Diversity measure Supply and demand concentration

The characteristics and visualization of critical heat flux of R-134a flowing in a vertical annular geometry with spacer grids

In the present paper, critical heat flux (CHF) experiments of forced convection boiling were performed to investigate the CHF characteristics of a vertical annular channel with one heated rod and four spacer grids for new refrigerant R-134a. The experiments were conducted under outlet pressure of 11.6, 13, 16 and 20 bar, mass fluxes of 100-600 kg/m2 s, and inlet temperatures of 25-40 ??C. The parametric trend of the CHF data was well consistent with previous understanding in water. The comparison between the present results with effect of the flow obstacle enhancing CHF and water data in similar geometry shows R-134a can be a modeling fluid for simulating water CHF in high pressure and high temperature condition even for annular geometry. The direct observation of flowing bubble behaviors contributes to enhancing our understanding on the effect of flow obstacles for flow boiling heat transfer.close3

ICONE10-22161 VIBRATION CHARACTERISTICS OF A VERTICAL ROUND TUBE ACCORDING TO HEAT TRANSFER REGIMES

ABSTRACT This paper presents the results of an experimental work o