Economic evaluation of demand‐side energy storage systems by using a multi‐agent‐based electricity market

With the wholesale electric power market opened in April 2005, deregulation of the electric power industry in Japan has faced a new competitive environment. In the new environment, Independent Power Producer (IPP), Power Producer and Supplier (PPS), Load Service Entity (LSE), and electric utility can trade electric energy through both bilateral contracts and single‐price auction at the electricity market. In general, the market clearing price (MCP) is largely changed by the amount of total load demand in the market. The influence may cause a price spike, and consequently the volatility of MCP will make LSEs and their customers face a risk of higher revenue and cost. DSM is attractive as a means of load leveling, and has an effect on decreasing MCP at peak load period. Introducing Energy Storage systems (ES) is one DSM in order to change demand profile at the customer side. In the case that customers decrease their own demand due to increased MCP, a bidding strategy of generating companies may be changed. As a result, MCP is changed through such complex mechanism. In this paper the authors evaluate MCP by multi‐agent. It is considered that customer‐side ES has an effect on MCP fluctuation. Through numerical examples, this paper evaluates the influence on MCP by controlling customer‐side ES corresponding to variation of MCP. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(3): 36–45, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20658     

Tunable dispersion equalizer with a divided thin-film heater for40-Gb/s RZ transmissions

We have developed tunable dispersion equalizers with a chirped fiber grating on the divided thin-film heater. The divided thin-film heater took an important role in the control of dispersion and dispersion slope. We successfully demonstrated the dispersion control from -304 to -196 ps/nm, the dispersion slope control from +100 to -300 ps/nm², and good performance in 40-Gb/s return-to-zero transmission by using this tunable dispersion equalizer     

ITER tungsten divertor design development and qualification program

In November 2011, the ITER Council has endorsed the recommendation that a period of up to 2 years be set to develop a full-tungsten divertor design and accelerate technology qualification in view of a possible decision to start operation with a divertor having a full-tungsten plasma-facing surface. To ensure a solid foundation for such a decision, a full tungsten divertor design, together with a demonstration of the necessary high performance tungsten monoblock technology should be completed within the required timescale. The status of both the design and technology R&D activity is summarized in this paper.     

Possible Biosynthetic Pathways for all <Emphasis Type="Italic">cis</Emphasis>-3,6,9,12,15,19,22,25,28-Hentriacontanonaene in Bacteria

A very long chain polyunsaturated hydrocarbon, hentriacontanonaene (C31:9), was detected in an eicosapentaenoic acid (EPA)-producing marine bacterium, which was isolated from the mid-latitude seashore of Hokkaido, Japan, and was tentatively identified as mesophilic Shewanella sp. strain osh08 from 16S rRNA gene sequencing. The geometry and position of the double bonds in this compound were determined physicochemically to be all cis at positions 3, 6, 9, 12, 15, 19, 22, 25, and 28. Although C31:9 was detected in all of the seven EPA- or/and docosahexaenoic acid-producing bacteria tested, an EPA-deficient mutant (strain IK-1Δ8) of one of these bacteria had no C31:9. Strain IK-1Δ8 had defects in the pfaD gene, one of the five pfa genes responsible for the biosynthesis of EPA. Although Escherichia coli DH5α does not produce EPA or DHA inherently, cells transformed with the pfa genes responsible for the biosynthesis of EPA and DHA produced EPA and DHA, respectively, but not C31:9. These results suggest that the Pfa protein complex is involved in the biosynthesis of C31:9 and that pfa genes must not be the only genes responsible for the formation of C31:9. In this report, we determined for the first time the molecular structure of the C31:9 and discuss the possible biosynthetic pathways of this compound.     

Three-dimensional observation of nanoscale ferroelectric domains using scanning nonlinear dielectric microscopy with electric field correction by Kelvin probe force microscopy

An advanced technique for the measurement of three-dimensional ferroelectric domain structure is described. Scanning nonlinear dielectric microscopy is used to measure the polarization components both perpendicular and parallel to the specimen surface. A nanoscale electric field correction is devised and performed using Kelvin probe force microscopy to allow more precise measurement of the nanoscale polarization component parallel to the specimen surface. Using this electric field correction, three-dimensional imaging of the ferroelectric polarization orientation is demonstrated.     

A study of economic evaluation of demand‐side energy storage system in consideration of market clearing price

In Japan the electricity market will open on April 1, 2004. Electric utility, Power Producer and Supplier (PPS), and Load Service Entity (LSE) will join the electricity market. LSEs purchase electricity based on the Market Clearing Price (:MCP) from the electricity market. LSEs supply electricity to the customers that contracted with the LSEs on a certain electricity price, and one to the customers that introduced Energy Storage System (:ES) on a time‐of‐use pricing. It is difficult for LSEs to estimate whether they have any incentive to promote customers to introduce ES or not. This paper evaluates the reduction of LSEs' purchasing cost from the electricity market and other LSEs' purchasing cost by introducing ES to customers. It is clarified which kind of customers has the effect of decreasing LSEs' purchasing cost and how much MCP of the whole power system the demand‐side energy storage systems change. Through numerical examples, this paper evaluates the possibility of giving the cost merit to both customers with energy storage systems and LSE by using real data for a year's worth of MCP. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(1): 22–35, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20447     

Growth of crack-free lithium tetraborate (Li2B4O7) single crystals

Abstract

The mode of occurrence and the origin of cracking of lithium tetraborate (Li₂B₄O₇) during growth by CZ method have been investigated. It is considered that crystal cracking can be divided into two main modes of occurrence. Each origin of cracking have been examined; 3-inch-diameter crack-free Li₂B₄O₇ have been successfully grown.     

Stepwise ethanolysis of tuna oil using immobilized Candida antarctica lipase

Ethanolysis of fish oil under mild conditions has been strongly desired for preparing the starting materials for the purification of ethyl docosahexaenoate. Thus, we attempted ethanolysis of tuna oil using immobilized Candida antarctica lipase. The immobilized lipase was inactivated in the presence of 2 3 molar equivalent of ethanol against the total fatty acids in tuna oil. To avoid such inactivation, the first step of ethanolysis was conducted at 40 degrees C in a mixture of tuna oil and 1 3 molar equivalent of ethanol using 4% immobilized lipase. After a 10-h reaction, ethanol was consumed and 33% of tuna oil was converted to its corresponding ethyl esters (E-FAs). The reactant is named Gly/E-FA33. The lipase was not inactivated in the presence of 2 3 molar equivalent of ethanol against the total fatty acids in Gly/E-FA33. These findings and the consideration of several factors affecting ethanolysis of tuna oil led to the development of the two- and three-step ethanolyses. The two-step reaction was performed as follows: the first step was carried out at 40 degrees C for 12 h in a mixture of tuna oil and 1 3 molar equivalent of ethanol with 4% immobilized lipase; the second step was performed for 36 h (total reaction period, 48 h) after adding 2 3 molar equivalent of ethanol. On the other hand, the three-step reaction was conducted as follows: the first step was conducted under the same conditions as those in the two-step ethanolysis; in the second and third steps, 1 3 molar equivalent of ethanol was added after 12 and 24 h, respectively; and in the third step, the mixture was shaken for 24 h (total, 48 h). Both types of ethanolyses achieved the conversion of 95% or more of tuna oil to its corresponding E-FAs. To investigate the lipase stability, the two- and three-step ethanolyses were repeated by transferring the enzyme to a fresh substrate mixture of the first step after finishing one cycle of reaction. The two- and three-step reactions maintained over 95% of the conversion for 70 d and over 100 d, respectively.     

Impact of duration of caregiving on stress among primary caregivers of elderly

This study examined (1) the direct effect of the duration of caregiving on caregiver psychological distress, and (2) two- or three-way interactions between duration, stressors (elderly's physical and cognitive impairments), and personal (caregiver's economic or work status) or social (informal or formal supports) resources. We interviewed 833 primary family caregivers of non-institutionalized frail elderly who had been selected through a screening process of all residents aged 65 and over (21,567 persons) in a suburban area of Tokyo. Caregiver psychological distress was evaluated by "Caregiving Burden Scale" as a caregiving-specific psychological measurement, and "Center for Epidemiologic Studies Depression Scale (CES-D)" as a general psychological measurement. The results were as follows. 1. For Caregiving Burden, duration showed a direct effect, as those who had been providing care for a longer duration of time reported higher burden. We found no interactions between duration, stressors, and resources on caregiving burden. 2. For CES-D, duration had interactions, but no direct effect. (1) Two-way interactions were observed between duration and caregiver's economic or work status, as caregivers with a low economic status or who were unemployed showed a stronger negative impact from duration of caregiving. (2) Three-way interactions were observed between duration, the elderly's ADL impairment, and informal support. Informal support, such as a secondary caregiver, buffered the negative impact of the elderly's ADL impairment in cases with a shorter duration of caregiving, but not for those with longer duration. (3) Three-way interactions were observed between duration, the elderly's cognitive impairment, and formal emotional support. Formal emotional support buffered the negative impact of the elderly's cognitive impairment for those with a longer duration of caregiving, but not for those with a shorter duration. These findings suggest that stress-buffering resources differ according to duration of caregiving.     

Effects of mongoose odors on rat capture success

Wild rats,Rattus norvegicus, R. exulans, andR. rattus, avoided wire-cage live traps that had previously captured mongooses,Herpestes auropunctatus. Replacing traps soiled by mongooses with clean traps would increase rat capture success and reduce a source of experimental bias.