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Low-carbon technologies will play a vital role in the realization of environmentally sustainable economies. However, uncertainties remain as to the feasibility of their development and implementation. Therefore, possible scenarios for the potential of these technologies should be considered to allow for flexible decision-making with respect to long-term energy strategies in Japan. This study evaluates the role of hydrogen in future energy systems in Japan using a MARKet ALlocation (MARKAL) model. A range of uncertainties are considered for nuclear power generation and carbon capture and storage (CCS) from fossil power generation. Our results suggest that an 80% reduction of CO2 emissions from the 2013 level by 2050 requires emissions from the electricity sector to decrease to nearly zero. Hydrogen power must play a functional role in future energy systems in Japan, but its contribution should depend on nuclear power and CCS.

This paper aims to identify psychological characteristics of potential investors of socially responsible investment (SRI) in Japan to explain its possible motivation by economic experiments. We asked subjects to make decisions regarding stock investments on the basis of three attributes of return, variance, and corporate social responsibility (CSR). We also conducted a dictator game and two lottery-choice experiments to measure subjects' psychological characteristics: altruism, risk aversion, and time discount rate. Applying a conditional logit model as well as mixed logit model, we found that people who have a higher time discount rate tend to be SRI investors.

Appearance is often key to the success of consumer-oriented products. This paper investigates the influence of visual appeal of renewable energy systems on consumer preference in a case study of residential solar panels. Two surveys of US residents were conducted with 194 and 350 responses, respectively. The first focused on aspects of solar panel appearance, including color, surface pattern and frame, while the second examined the tradeoffs between solar panel appearance, functional performance and price. Respondents were presented with two types of visual representations: solar panel images alone or solar panel images shown in the context of use. Results showed that respondents in general preferred black solar panels that had solar cells with rounded corners and even surfaces, and preferred solar panels that matched the color of the roof. It was also found that respondents were willing to pay a higher price for better-looking solar systems. This effect was found to be stronger with contextualized images of solar panels on roofs.

Maintenance plays a critical role in reducing operating cost and maximizing reliability of a complex engineering system. This paper proposes a novel maintenance-focused, system-level design framework that attempts to capture the interactions between maintenance strategies and system-level design parameters overlooked in current modeling approaches. The goal of this maintenance-focused approach is to help designers better understand the interconnectedness of system architecture, choice of maintenance strategy, and uncertainties in a design. Application of the proposed design framework is demonstrated through a case example of a power plant condenser system. Results show that using an integrated approach can reveal the many nonobvious interactions between subsystems, and produce system designs that have lower life-cycle cost compared to traditional sequential design approaches.

The design of complex systems involves selecting design parameters to satisfy the required constraints while meeting desired performance objectives. These parameters are often coupled and their relationships not easily understood. This paper presents results of an experiment to understand how designers solve parameter design problems, in the context of desalination systems. Subjects with different desalination expertise were asked to complete design tasks involving seawater reverse osmosis plants. Results confirmed that designers had difficulties understanding the sensitivity of coupled variables. More desalination knowledge was linked to better performance and designers with limited desalination knowledge tended to perform the worst due to having partial or incorrect domain knowledge. These findings have implications in design tool development and education.

Research on complex system optimization has focused on areas including algorithms, coordination strategies, and communication tools. This paper considers optimization from the perspective of information coordination during the solution process. This work aims to determine the potential impact of factors including the role of a system facilitator in managing system-level tradeoffs, the influence of an ideal information scenario, the choice of system variables, and the amount and form of passed information. The goal is not to develop the “best” communication structure or optimization algorithm, but to understand the significance of these factors. A traditional multidisciplinary design optimization coordination framework, a game theoretic approach, and a modified game theory approach are used to mimic design team behaviors. Results suggest these factors can influence the coordination process outcomes: The choice of system variable plays a significant role in the optimality of the final design; perfect inform...

Peptidylarginine deiminase (PAD; EC 3.5.3.15) is a post-translational modification enzyme that catalyzes the conversion of protein-bound arginine to citrulline (deimination) in a calcium ion dependent manner. Although PADI genes are widely conserved among vertebrates, their function in the chicken is poorly understood. Here, we cloned and sequenced three chicken PADI cDNAs and analyzed the expression of their proteins in various tissues. Immunoblotting analysis showed that chicken PAD1 and PAD3 were present in cells of several central neuron system tissues including the retina; the chicken PAD2 protein was not detected in any tissue. We expressed recombinant chicken PADs in insect cells and characterized their enzymatic properties. The chicken PAD1 and PAD3 recombinant proteins required calcium ions as an essential cofactor for their catalytic activity. The two recombinant proteins showed similar substrate specificities toward synthetic arginine derivatives. By contrast to them, chicken PAD2 did not show any activity. We found that one of the conserved active centers in mammalian PADs had been altered in chicken PAD2; we prepared a reverse mutant but we did not detect an activity. We conclude that chicken PAD1 and PAD3 might play specific roles in the nervous system, but that chicken PAD2 might not be functional under normal physiological conditions.

User-centered approaches to design can guide teams toward an understanding of users and aid teams in better posing design problems. This paper investigates the role of user-centered design approaches in design process and outcome within the context of design team projects. The value of interaction with users is examined at several stages throughout the design process. The influence of user-centered design on the performance of design teams is also explored. Results suggest that the quantity of interactions with users and time spent interacting with users alone is not linked with better design outcome, but that iterative evaluation of concepts by users may be of particular value to design prototypes. Suggestions are made based on the reflections from the authors after conducting this study.

In this work, an estimate of the elevation of airborne lead concentrations via the lead solder contained in domestic electricity installations and an investigation into the effects of human exposure were conducted using a simulation method. The elevation of airborne lead concentrations due to incineration was calculated to be 0.001 µg/m3 maximum. The simulation results of the calculations indicated that blood lead concentrations could reach as high as 10−5 µg/dl. These concentrations could primarily be attributed to the inhalation of airborne lead particles. In addition, we discuss the influences of lead solder disposal on the ecosystem via soil and water.

The chemisorption of O2 on nanoscale n-doped CdS semiconductors is computed in terms of a Wolkenstein isotherm coupled to the Schrodinger Poisson equation. Present numerical results show the dependence of the chemisorbed charge and the differential capacitance on oxygen partial pressure. A comparison against the classical Poisson-Boltzmann approach shows a higher chemisorbed charge in the quantum model, but a greater differential capacitance in the classical case.