Reproducing solar curtailment with Fourier analysis using Japan dataset

The 6th International Conference on Power and Energy Systems Engineering (CPESE 2019), 20–23​ September 2019, Okinawa, Japan.Curtailment of variable renewable energy increases the Levelized Cost of Energy (LCOE), which is the tool often used to compare its profitability against traditional energy sources. Recently, the Kyushu Region of Japan had to curtail some of its solar production to meet energy balance. As many countries increase their solar energy production, curtailment will be inevitable. It is therefore important to develop methodologies to calculate it. In the case of Japan, curtailment can easily be estimated using hourly data. However, such data is unavailable in other countries. In this study, a methodology to reproduce curtailment using known periodicity and statistical data is presented. Insights were initially generated by simulating future curtailment scenarios of Kyushu to extract the factors that affect curtailment. Fourier analysis was used to identify the periodicity of demand and solar production. The Fourier representation was simplified using the identified factors. Along with statistical data, the demand and solar data were approximated and the curtailment was reproduced. Results show that curtailment can be closely reproduced using the proposed methodology on a yearly and monthly level. Further research is necessary to test the methodology for other conditions like having different climate, varying daily fluctuations, and other human-related fluctuations

Hsp105 but not Hsp70 family proteins suppress the aggregation of heat-denatured protein in the presence of ADP

AbstractHsp105α and Hsp105β are mammalian members of the Hsp105/110 family, a diverged subgroup of the Hsp70 family. Here, we show that Hsp105α and Hsp105β bind non-native protein through the β-sheet domain and suppress the aggregation of heat-denatured protein in the presence of ADP rather than ATP. In contrast, Hsc70/Hsp40 suppressed the aggregation of heat-denatured protein in the presence of ATP rather than ADP. Furthermore, the overexpression of Hsp105α but not Hsp70 in COS-7 cells rescued the inactivation of luciferase caused by ATP depletion. Thus, Hsp105/110 family proteins are suggested to function as a substitute for Hsp70 family proteins to suppress the aggregation of denatured proteins in cells under severe stress, in which the cellular ATP level decreases markedly

Global Zero Emission Scenario: Role of Innovative Technologies

AbstractThis study investigated a zero emission scenario with following two originalities compared to various existing studies. One is that we based on A1T society of SRES (Special Report on Emissions Scenario) of IPCC (Intergovernmental Panel on Climate Change) compared to existing studies on those of B1 or B2. The second one is that various innovative and radical technologies were considered and incorporated, such as biomass energy with CCS (BECCS), and advanced nuclear technologies including hydrogen or synfuel production. We applied a global modeling, whose energies, materials, and biomass and foods supply costs were minimized by linear programing with time horizon up to 2150. We found following features of energy supply structure in A1T scenario. Since the electric demand in A1T scenario in 2100 is two times larger than the others, 1) renewable energy which solely produce electricity, nuclear, and fossil energy with CCS (FECCS) especially coal are main sources of electricity, 2) renewable which can supply heat, namely BECCS and geothermal, satisfies the sector, and 3) hydrogen from coal is introduced in transport sector. It can be concluded that the zero emission energy systems with global economic growth will be possible, by development and deployment of ambitious advanced energy technologies

Assessing the geospatial nature of location-dependent costs in installation of solar photovoltaic plants

A major hurdle in increasing the economic feasibility of solar photovoltaic (SPV) plants is the ever-increasing share of location-dependent costs (land, transmission, labor, etc.) in total installation costs. Such costs are geospatial in nature, due to spatial socio-economics affecting them. Present geolocation methods, for locating SPV installation sites, do not consider the effect of location-dependent costs in installation. We use a spatial parameterization model for examining the factors causing spatial variation of the installation costs of land, labor, transmission and supply chains for suburban SPV plants, within a geographic boundary. The model is applied to Kolkata city, India, and the spatial variation of the costs are checked in a 2500 km²2 suburban boundary. The spatial variation of the location-dependent costs is mainly caused by the distance from an economic focal point of the city. The variations significantly optimize at minima points in the 2500 km² boundary, where the location-dependent costs increase by 10% with an average 2.6 km deviation and an average 6.7 km deviation from the global minima, for small and large plants, respectively. The spatial minima is mainly caused by variance of land and transmission costs. This minima location lies on the extrapolation of a line that connects the city focal point with the substation. The capacity of the SPV plants at the optima increases with increasing transmission voltage (11 kV to 66 kV), ranging from 4 MW to 257 MW in the case-study (small to large scale), while the minima shift away from the city focal point (ranging 29 km to 48 km) with increasing capacity. This study provides a perspective on how the spatial variation of installation costs can play a role in the geolocation of SPV plants. Furthermore, the empirical and spatial variation of location-dependent costs can enable energy planners to evaluate the economic feasibility of solar power and promote better land-use near cities

Enhanced Photocatalytic Activity of BiVO4/Bi2S3/SnS2 Heterojunction under Visible Light

Heterojunction photocatalysts have attracted a significant amount of attention due to their advantages over a single photocatalyst and, particularly, their superior spatial charge separation. Herein, the BiVO4/Bi2S3/SnS2 heterojunction was synthesized via solvothermal synthesis with different ratios of BiVO4 to SnS2. The photodegradation rate of the 0.03 BiVO4/SnS2 sample for rhodamine B removal is 2.3 times or 2.9 times greater than that of a single SnS2 or BiVO4, respectively. The chemical bond between photocatalysts is confirmed by X-ray photoelectron spectroscopy (XPS), and the synchronized shift observed in binding energies strongly indicates the electron screening effect at the heterojunction. A Z-scheme model is proposed to explain charge transfer pathway in the system, in which the formation of Bi2S3 plays a crucial role in the enhanced photocatalytic performance of the heterojunction

An Integrated Model Approach: Exploring the Energy Literacy and Values of Lower Secondary Students in Japan

Energy literacy is a minimum required capacity for developing a sustainable society that participates in and discusses on energy and environmental (EE) issues. Understanding the energy literacy structure is of significant importance for providing effective energy education to promote people’s awareness of EE issues. In this article, an energy literacy structural model integrated with the Theory of Planned Behavior and Value-Belief-Norm Theory was investigated for 1070 lower secondary students (ages 13-15) in Japan. Structural equation modeling uncovered that the awareness of consequences is the most powerful predictor for the causality between basic energy knowledge and energy-saving behavior through the attitude toward the energy-saving behavior. A conditional process analysis elucidated that (1) the conditional effect of basic energy knowledge on the awareness of consequences depends on scientific literacy, critical thinking ability, and environmental worldview, and (2) the conditional direct and indirect effects in the mediation model of awareness of consequences on the attitude toward energy-saving behavior through the ascription of responsibility depend on environmental worldview or values and family discussion of energy-related issues. The energy literacy model proposed provides a theoretical contribution to the development of an effective energy education program

Clinical Relevance of Parafoveal Intercapillary Spaces and Foveal Avascular Zone in Diabetic Retinopathy Without Macular Edema

Purpose: To investigate the clinical significance of intercapillary spaces on swept source optical coherence tomography angiography images in diabetic retinopathy. Methods: We retrospectively reviewed 110 eyes of 110 patients suffering from diabetic retinopathy without macular edema for whom 3 × 3 mm swept source optical coherence tomography angiography images centered on the fovea were obtained. Automatic image processing of the superficial slab images allowed us to define the areas encircled by retinal vessels as intercapillary spaces within the central 2-mm circle. We evaluated how the quantitative parameters of intercapillary spaces are associated with logMAR and feasible to diagnose diabetic macular ischemia. Results: Total counts (ρ = −0.419; P < 0.001) rather than morphologic parameters of the intercapillary spaces showed a significant correlation with logMAR. There were individual levels of correlations between logMAR and counts of intercapillary spaces in individual sectors. In particular, the summed numbers of the spaces in three highly significant sectors were more significantly associated with logMAR (ρ = −0.515; P < 0.001). Multivariate analyses confirmed that the number of the intercapillary spaces (β = −0.266; P = 0.016) and foveal avascular zone area (β = 0.227; P = 0.042) were related to logMAR. The clustering using the foveal avascular zone area and the number of intercapillary spaces revealed two major clusters; one had fewer intercapillary spaces (P < 0.001) and poorer logMAR (P < 0.001) than the other, with a wide range of the foveal avascular zone area. Conclusions: Decreased intercapillary spaces contribute to visual impairment in diabetic retinopathy and suggest one possible criterion of objective diagnosis of diabetic macular ischemia

Inter-brain synchronization in the client-therapist relationship during sandplay therapy: an exploratory study

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The intercapillary space spectrum as a marker of diabetic retinopathy severity on optical coherence tomography angiography

Microcirculatory disturbance plays a pivotal role in the pathogenesis in diabetic retinopathy (DR). We retrospectively quantified the total counts and morphological features of intercapillary spaces, i.e., intercapillary areas and nonperfusion areas (NPAs), on swept-source optical coherence tomography angiography (SS-OCTA) images and to evaluate their associations with DR severity grades. We acquired 3 × 3 mm OCTA images in 75 eyes of 62 diabetic patients and 22 eyes of 22 nondiabetic subjects. In the en-face superficial images within the central 2 mm, the areas enclosed by retinal vessels were automatically detected. Their total numbers decreased in some eyes with no apparent retinopathy and most eyes with DR, which allowed us to discriminate diabetic subjects from nondiabetic subjects [area under the receiver operating characteristic curve (AUC) = 0.907]. The areas and area/perimeter ratios continuously increased in DR, indicating a continuum between healthy intercapillary areas and NPAs. The number of intercapillary spaces with a high area/perimeter ratio increased according to DR severity, which showed modest performance in discriminating moderate NPDR or higher grades (AUC = 0.868). These quantified parameters of intercapillary spaces can feasibly be used for the early detection of microcirculatory impairment and the diagnosis of referable DR