System Architecture Design For Integrated Grid

EPRI SEMINAR : INTEGRATED GRID CONCEPT AND TECHNOLOGY DEVELOPMENT System Architecture Design For Integrated Grid August 20, 2015 Hideo Ishii, Ph.D. P...
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EPRI SEMINAR : INTEGRATED GRID CONCEPT AND TECHNOLOGY DEVELOPMENT

System Architecture Design For Integrated Grid August 20, 2015 Hideo Ishii, Ph.D. Professor Advanced Collaborative Research Institute for Smart Society (ACROSS) & Research Institute for Advanced Network Technology (RIANT)

Waseda University

Copyright ©2015 Waseda University, All Right Reserved

OUTLINE  Paradigm Change in Electric Energy System

in Japan : Need of Integrated Grid - 3.11 : Demand-side Integration, Distributed System - Electric Power System Reform

 Two Major Challenges - Demand Response - Photovoltaic Integration

 Demonstration Projects  System Architecture Copyright ©2015 Waseda University. All Right Reserved

1

Change in the electric energy policy through “3.11” After “3.11” Before “3.11”

+

Electricity saving Peak cut in electricity demand

Realization of Low Carbon Society by deploying energy management system Installation of high-efficiency equipments & appliances Integration of renewable energy Integration of EV/PHV Balancing demand-supply for electricity & gas etc.

Missing significant amount of base load supply Copyright ©2015 Waseda University. All Right Reserved

2

Smart Grid Smart Community

Pumped-up Hydro Power Hydro Power

Smart Building

Thermal Power

Electric Power NW (Power Grid)

Buildings with PV generation/ Private Generator/Battery

Control by ICT

Smart House Energy storage

Substation

Smart Meter PV panel

Environmental Impact Impact of Smart Grid PV Power Station

¥ EV

Wind Farm

Renewable Energy Sourse Power Quality Issue (frequency, voltage)

Hp Water Heater

Alternative value Energy Cost

Battery

Fuel Cell

Scheme for electricity saving With incentive

【Control Center governing optimum energy flow】 Energy Management System (EMS)

GEMS (Grid)

BEMS (Building)

HEMS (Home) TD Network

CEMS (Community)

Electricity Flow

DATA Flow

3

Movement to be the most advanced country regarding energy

Various Energy Supply & Smart Energy Use Generate

Production (Procurement)

Diversified/Low-priced Diversity/Renewable etc.

Transmit

Use

Transport

Flexible/Selectable/Efficient Electricity System Reform

【Reconstruction of Energy Mix】 ◎Reconsideration of FIT system

◎Target of co-generation system installation ◎Restart of nuclear power with approval

【Improving grid to “smart grid”】 ◎Electricity system reform ①stable supply ②suppression of price ③enlargement of choice and opportunity ・1st stage(2015): Establishment of ONCTO (Organization for Nationwide Coodination of Transmission Operators)

・2nd stage(2016): Full liberalization of retail market ・3rd stage(2018-2020) : Unbundling T&D sector

Consumption Smart

Energy Saving Standard DR / Nega-watt trading 【Promotion of Smart Energy Use】 ◎Reinforcement of energy saving at buildings / houses ◎Promotion of effective EMS (supporting DR) ◎DR based on negawatt trading GL

【Revision of Energy Saving Standard / as obligations 】 ◎Performance:consumption of primary energy source

◎Evaluation object (newly added): energy creation system (PV, etc.) performance of individual facilities (HVAC, water heater, lighting, etc.)

◎Establishment of Interoperability(smart grid) ・Remote control of renewables ・Control of consumer devices/EMS

4

Business operators and their role after the reform Full liberalization of retail market (2016~) Generation Simultaneously commensurate Competition & generation plan diversity

Control of demand-supply balance (ensuring power quality)

※Names are all tentative.

Power Generation Operators

Smaller Power Generation Operators

Private generation

Useネットワーク利用 of network

(託送供給) Network Operators (Transportation service) Fairness & (Type I, Type II, Type III)

Network neutrality

Retail Simultaneously commensurate Competition & demand estimation diversity

Retail Operators

All consumers

Private use

5

Entire sketch of demand-supply balance after the reform Use of DR for nega-watt transaction with network operator

Supply Side

Procurement Side

Generation Operator

Network Operator

Retail Operator

kW

kW

Capacity Market

kW,kWh

Long term transaction

kW,kWh

Short term transaction

kW,kWh

Spot transaction (a-day-ahead/of the day)

Real time Transaction Adjustability

Ancillary service

Capacity (kW) Adjustability

Base load supply Middle load supply Peak load supply

Nationwide ancillary market Other areas 6

Imbalance adjustment deviating from simultaneously commensurate plan and relevant cost

Actual 70MWh

Gen. plan(A)

Gen. actual(A)

100MWh

Generator trouble

Shortage imbalance

Imbalance adjustment in Gen. side

50MWh

Imbalance 50MWh Shortage

Supply imbalance

Gen. Actual(B)

Gen. plan(B) 100MWh

Gen. plan(C) Shortage imbalance

70MWh 190MWh 100MWh Demand plan(D) 100MWh

Demand plan(E)

Imbalance fee

100MWh

Gen. plan(C)

Demand excess

Imbalance adjustment in Demand side

Imbalance 20MWh shortage

Supply imbalance

Demand actual(D) Surplus imbalance

80MWh Demand



Actual

Difference of power between plan and actual becomes imbalance in Gen. side and demand side. Network operator will adjust in both side.

70MWh

When Gen A and Gen B is kept by Retail company D, it is necessary to match demand and supply plan of company D.

Retail Operator

Plan

Demand shortage

Imbalance 20MWh Surplus actual(E)

Imbalance fee

Purchase imbalance

Imbalance fee

Network Operator

Gen. Operator

Plan

Supply Adjustability

Adjustability producer

Waiting fee

-Gen. operator -DR aggregator

Usage-based fee

① This is internal transaction between Gen. Div. and Network Div. in one company while the adjustment is done in the general electric utility. ② Used for not only the adjustment of imbalance, but frequency control within 30 minutes. ③ Payment from Adjustability producer to Network operator is feasible in case of generation power suppression.

7

Roll of ONCTO ONCTO(*)

Area A

supply

Business role of ONCTO ① Coordinating supply and demand planning, grid planning, promoting capacity increase of frequency converters and inter-region tie lines as well as nationwide grid operation beyond the regions ②Coordinating inter-regional grid operation regarding supply-demand balance and frequency regulation under normal circumstance ③Conducting regulation of supply and demand by directing increase of power generation, power interchange and all under stringency due to disasters, etc. ④Reception of grid connection of new generators, information disclosure as a neutral organization

Area C

supply Area B

(*)Organization for Nationwide Coordination of Transmission Operators

Realize 900MW of capacity increase as early as possible

60Hz 50Hz

5,570MW Hoku16,660MW riku Chugoku Kansai 300M 5,570 5,570MWW MW 2,400 Chubu MW 1,400 Kyushu Shikoku MW

Hokkaido

AC/DC converter 600MW W Tohoku 12,620MW Tokyo

Frequency converter 1,200MW

Targeting capacity increase up to 2,100MW by 2020, and to 3,000MW as early as possible afterward 8

Treatment of FIT associated with system reform Coordinating body for cost allocation

【Basic scheme】

grant

surcharge Sell with other sources

Power supply (renewable) 【Specific contract】 Power generation operator of renewable energy

Retailor

Consumer ※2

Residential PV, etc.

NW operator

※1 【Connection contract】

【Priority connection】 Renewable energy sources are to be connected to network unless there are rational reasons to deny. 【Priority power supply】 Balanced supply and demand ThermalThermal

Nuc. RE

D

D

D

D

Decrease in demand

Thermal

Thermal

Nuc. RE

D

D D

D

Suppress from conventional (thermal) generation

※1 Contract to allow generation facilities connection to NW ※2 NW operator coordinates imbalance if necessary.

To be discussed at ONCTO established in April, 2015 ・NW utilization rule ・RE output control ・Utilization of interregional tie lines 9

Paradigm Change in Electric Energy System  Electric Power System Reform  Large scale RE installation  Large Power Plants + Bulk

Grid

 Cooperation with Distributed System - Various Resources: e.g. EV, Battery - Integration vs Local Optimum

 Demand : Given (Forecast)

 Demand : Control - DR, Nega-watt Trading

 Vertically Integrated

 Horizontally Divided - New Rules, e.g. Simultaneous Equivalence

 Power Flow : one way

 Power Flow : bi-directional

 Basically Dispatchable

 Intermittent (Renewable)

Generation Copyright ©2015 Waseda University. All Right Reserved

10

Then, the issue is ……  How to achieve “stable power supply” without lowering quality of electricity as well as raising price under the new framework.  This challenge could be one of major examples of EPRI’s “Integrated Grid”.

Copyright ©2015 Waseda University. All Right Reserved

11

Supply-Demand Balance Control Variation of Total Demand A few tens of min~ several hours component A few min. ~ A few tens of min. component

Amplitude of demand variation

Demand

Variation from RE

EDC LFC

GF

20sec. 2~3min.

A few sec. ~ A few min. Time

10~20min.

Variation period

EDC(economic load dispatching control) Forward control based on demand prediction LFC(Load Frequency Control) For unpredictable demand variation (1~2% of total demand) GF(Governor-Free) For fast demand variation which can not be covered by LFC Copyright ©2015 Waseda University. All Right Reserved

12

Challenges in New Paradigm  New Electric Energy System  Two-way power flow  Combination of central & distributed control  Co-existence of different optimization : supply-demand balance & new values - maximum use of renewable energy recourses - efficient use of energy including heat, transportation, etc.  Resiliency : preparation for emergency

 New kind of Control for Grid Operator Demand Response and PV Generation  Not necessarily owned by grid operators  Various sizes  The smaller, the larger the number

Copyright ©2015 Waseda University. All Right Reserved

13

DR

①Request to reduce demand

Normal Community Contract power level

request

Consumption

Electrical Demand

DR aggregator DR Server

ISO/TSO Retailor

③Measure and report ④Payment for DR result

Reduce

CEMS

Buildings

BEMS

②Control to shift the peak

Automated Demand Response: (ADR)

Time

Condominium

MEMS Autonomy

Consumption

Emergency Prior supply to important appliance in a range of available power

Brown out

Emergency

Resilience Houses

HEMS

Time 14

METI Demand Response Project Smart House/Building Standardization Study Group Waseda Project Member

Test & Verification

Standardization

Demand Response Task-Force

 Working group for National Standard Development  “ADR Association” for outside activity

Waseda Project Mission

 R&D and demonstration of Demand Response technology along with global standards Copyright ©2015 Waseda University. All Right Reserved

15

METI’s Official Announcement @ 3rd Meeting of “Study Group on Promoting Standardization and Business of Smart-Houses and Buildings” (May 15, 2013)  Study on DR technology and Standard - Summarize use cases of demand response (DR) and prepare a standard method for automated DR between power utilities and aggregators based on OpenADR. - Establish test facilities developed at the Waseda test site.

 Specification and Policy - The standard method is described in the document “Specification for DR interface, Ver1.0” which covers OpenADR 2.0a and a part of 2.0b. - In this framework, vendors are supposed to develop their soft wares or hard wares in compliance with the conformance rule determined by OpenADR Alliance (Spec. 2.0a and/or 2.0b).

Copyright ©2015 Waseda University. All Right Reserved

16

Standardization of Communication Interface for DR Smart Houses

Utility

HEMS

ADR Server

(Aggregator) USER Data Base

Transmission standard:ECHONET-Lite

CEA-2045

+ DR Object

Smart Buildings BEMS

OpenADR

Open (competitive area?)

Copyright ©2015 Waseda University. All Right Reserved

17

ADR Association JAPAN  “ADR Association” was established under the Japan Smart Community Alliance for standardization of ADR and promotion of international cooperation.

Chief Director : Professor Ishii (Waseda University) 代表理事 : Hideo 石井英雄(早稲田大学) Director : Professor Hiroyuki Morikawa 理事アドバイザー : 森川博之(東京大学) (The University of Tokyo) 理事 : Matsumoto 松本純孝(東京大学) Sumitaka (The University of Tokyo) Ryutaro Toji (Waseda University) 田路龍太郎(NTT) Shigeo Matsuda (Toshiba)  Kick-off meeting for collaboration with

OpenADR Alliance (in CA, USA : November 1st, 2013)

Copyright ©2015 Waseda University. All Right Reserved

18

OpenADR  Open protocol for automated DR developed in US  Ensure certainty and interoperability  IP base, application layer  XML

 OpenADR 2.0 

  

Expansion and generalization of OpenADR 1.0 OpenADR Alliance 2.0a :simple device, e.g. thermostat 2.0b :support report, opt in/out etc. Copyright ©2015 Waseda University. All Right Reserved

19

Standardization of Communication Interface for DR Smart Houses

Utility

HEMS

ADR Server

(Aggregator) USER Data Base

Transmission standard:ECHONET-Lite

CEA-2045

+ DR Object

Smart Buildings BEMS

Transmission standard: BACnet, Lonworks, etc.

OpenADR

Open (competitive area?)

Copyright ©2015 Waseda University. All Right Reserved

20

Use cases summarized by DR-TF No.

Use Case

Actors

Description

UC-1

Aggregator DR

System operator/Retailer, Aggregator, customer

Aggregators procure DR from customers and provide to system operator and retailers

UC-2

Nega-watt trading A

System operator/Retailer, Aggregator, Market

System operator, retailers and Aggregators procure DR from market

UC-3

Nega-watt trading B

Market,/Retailer, Aggregator, customer

Retailers, aggregators and customers provide DR to market

UC-4

Capacity contract

System operator/Retailer, Customer

System operator and retailers procure DR from customers

UC-5

Direct load control

Aggregator, Customer

Implement DLC

UC-6

Broadcast

System operator/Retailer, Aggregator, customer

Inform tariff program

UC-7

Mutual contract (using tie line)

System operator/Retailer, Customer

Basically same as UC-4

Copyright ©2015 Waseda University. All Right Reserved

21

Status of the Specification  The “Specification for DR interface, Ver.1.0” was designed to

cover use cases (UC-1, 4 & 7) considered for implementation in summer, 2013.

 DR primarily between utilities and aggregators  Minimum specification in compliance with OpenADR2.0a/b

 The current version is “Specification for DR interface,

Ver.1.1a” expanded to include UC-5 and 6.

 The Spec. 1.1a had been tested and evaluated within Waseda

Project until March, 2015.

 After reflecting required modification, “Specification for DR

interface, Ver.1.1” was issues in June, 2015. Copyright ©2015 Waseda University. All Right Reserved

22

Waseda Project (Demand Response) TEPCO Power Supply Control Center

Waseda University EMS Shinjuku Demonstration Center

Smart House HEMS

ADR Signal

ADR Signal

ADR Signal

DRAS

TEPCO DR (BSP) Operation System TEPCO Proprietary DR Signal

ADR Signal

(Utility T&D role)

DRAS (Utility Retail role)

【Project A, D】 Connect to Aggregator ADR Signal

Web Server

ADR Signal

DRAS (Aggregator role)

【Project C】 Connect to Smart City

Smart Phone

【Project B】 ADR Standard Test site ADR Signal

4 Major City EMS field Trial

Kita Kyushu City EMS TEPCO DR (BSP) Keihanna Toyota Aggregator System City EMS City EMS

MEMS/BEMS/FEMS Test Site (Office and Factory) Yokohama City EMS

Standard ADR Signal TEPCO Proprietary DR signal

23

Demonstration project for incentive based DR  METI had contracted with TEPCO and six DR aggregators for a demonstration program regarding incentive based DR (Dec. 2013-Mar. 2015) which deals with not only a peak cut in summer but also ancillary service and economical replacement expanding the area of DR considering the forthcoming electric DR活動領域 power system reformation.  In this project, “Specification for DR interface, Ver.1.1a” was implemeted. price ISO/RTO

(yen/kW)

New DR area Price at JEPX

Retailer/Aggregator

Area of Economic replacement

Replacement of Supply Capacity

Image of incentive based DR demonstration Waseda EMS Demo. Center

DR implementer (Aggregator)

Curtailment Curtailment request

Ancillary service Peak cut (BSP)

Customer

Curtailment request Building Negawatt HVAC, light

Negawatt

Utility DRAS

¥ Incentive

Client DRAS

Generation ¥ Incentive Battery

Expected demand

Reliability

Factory facility

Generator

24

Demonstration project for incentive based DR : Phase 2    

Period : April, 2015 ~ March, 2016 Utility area : Tokyo, Kansai, Chubu Aggregators : 22 entities Target : Estimation of DR potential across Japan (Waseda) Evaluation of “Nega-watt Trading Guideline” ~ Base Line (Waseda)  DR program : 3 Categories - 10 min. ahead - 1 hour ahead - 1 day ahead DR MENU

10min ahead

1 hour ahead

1 day ahead

Incentive (kW)

JPY6,500/(kW-year)

JPY5,000/(kW-year)

none

Incentive (kWh)

JPY20/kWh

JPY20/kWh

JPY30/kWh

Base Line

Ave. 30min before event dispatch

High 4 of 5

High 4 of 5

Aug.-Oct. 13:00-17:00 (1 hour)

13:00-17:00 (2 hours)

13:00-17:00 (4 hours)

Nov.-Jan. 9:00-11:00/17:00-19:00 (1 hour)

9:00-11:00/17:00-19:00 9:00-11:00/17:00-19:00 (2 hours) (4 hours) 25

Period (duration)

DR : remaining issues and perspective  Expansion of Area  Base Line, Measurement, Certainty  Potential of DR across the Country

 Economic Value :

kW, kWh

 Consumer Engagement, Social Value of DR

 Aggregation :

Grid Code

 Establishment of Capacity Market  Fast DR :

Mitigation of RE variation Copyright ©2015 Waseda University. All Right Reserved

26

Operating and certificated capacity of PV (as of June, 2014)  Capacity Base (104kW)

FY2013 Peak Load : 157GW Certificated capacity

5,300

Target as of FY2030 : 53GW Countermeasure is strongly required !!

Operating capacity

Purchasing price (1kWh) 42 JPY residential non-residential 40 JPY (+TAX) Certificated capacity (accumulation)

38JPY 36 JPY (+TAX) Operating capacity (accumulation)

37 JPY 32 JPY (+TAX)

27

Power quality issues under massive integration of PV Smart school

PV Wind Battery

Distribution NW Energy management

Smart stores Etc.

Output relative to rating

Smart building

Variation of PV output (summer)

[%]

Frequency deviation due to surplus electricity 50±0.2H (East Jap)

sunny

cloudy

parking

rainy

ICT NW

[hr]

Voltage issue

Energy management

store

Golden week

60

load

suppression



Power flow Prescribed range 107V

30 Reverse power flow from PV

With PV

Voltage

Without PV Distance from substation

Suppression of PV output due to deviation of voltage from prescribed range

Surplus electricity

50 40

(101±6V) 95V

house

2.Shortage of freq. regulation capacity [%]

load荷 load

PV Wind Battry

Frequency issue

1.Suppression of reverse power flow

6000V

Co-generation

SS

load load

スbuilding

school

Smart house

substation 100/250V

consumption

supply)

20 10 0

(Pumped-up hydro) (pumping up) Thermal Nuclear

PV

hydro 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

[h]

Suppression of PV output due to deviation of network frequency from prescribed range (50±0.2 or 60±0.2)

Deviation from range of stable supply ⇒ unexpected disoperation, outage 28

METI’s Official Announcement The Agency for Natural Resources and Energy (ANRE) “Revision of the Current Operation System for the Feed-in Tariff Scheme toward the Maximum Introduction of Renewable Energy” (Dec 18, 2014)  Enlargement of renewable integration under the new output-control scheme - All the facilities will be subject to the output control - Shifting the current scheme for limiting renewable electricity output without compensation to the operators of renewable energy power generation facilities (socalled "30-days rule") from a daily basis to an hourly basis - Requiring the operators of renewable energy power generation facilities to introduce a remote output-control system - Specified Electricity Utility System (over integration)

 Approaches to expanding the future introduction of renewable energy

Source: http://www.meti.go.jp/english/press/2014/1218_01.html

29

Expanding capacity range of PV output suppression & Shift to 360hr-rule Day base suppression

PV output with no suppression

No compensation up to 30 days

PV output after suppression

Target: 500kW and larger

New rule

Bottom limit

Time base suppression No compensation up to 360hr per year

Bottom limit

PV output after suppression

Target: All PV (inc. residential)

Interface ・Standardization ・Guideline ・Control via telecommunication

Schematic of “Remote control of PV generation” Large scale PV generation(2000kW〜)

Power utility Internet / VPN (Private line) Regulation of Administration of Supply / demand delivery destination

Command data

Command

data

Command

PCS (Target of control)

Command デタ data

PV panel

Middle and small scale PV(10〜500 or 2000kW) Local private NW Controller with calendar (Telecom. / Admin.)

Internet / VPN Public NW/ Mobile NW

Distributor(Aggregator,vendor, etc.)

Controller

(Telecom./Admin.)

data

Administration of delivery destination

Local private NW

PCS (Target of control)

PV panel

Residential PV(〜10kW) HAN Controller with calendar (Telecom. / Admin.)

PCS (Target of control)

PV panel

30

30

Technical challenges and necessity of communication controls with standard interface ①Preparation of telecommunication NW ②Upgrading forecast of PV generation ③System for estimating control volume for each of vast amount of PV generation systems ④Function of regulating reverse power flow into grid for residential PV ⑤Ensuring security when telecommunication is unavailable upon power outage, etc

Standardization of system interface Deal with plural rules ・Use case ・Starting/ending time ・PV suppression period ・Amount of PV suppression

Achievement of collective remote-control of PV suppression for several hundred thousand houses with PV 【demerits without standardization】 Lack of unification in interfaces of a communication control system among network operators, aggregators and PV operators ⇒ rise in total cost 31

DR to save demand and to suppress renewable energy generation

Legacy DR (Deamnd Cut and peak shift) Energy Producer

Demand

Demand

TIme

Energy consumer

Request to reduce

demand

OpenADR Event information • date, time, duration • reduction: kW Adjustability producer

Energy producer

Future DR

Adjustability consumer

Request to suppress renewable energy power generation

PV

PV

Prosumer (Producer+Consumer) Time

32

DR(Reduce/Increase demand) and Suppress PV

Request to suppress RE gen.

DR Aggregator

(Reduce demand) Demand

Demand

Normal Gen. PV

PV

Suppress Gen.

DR Aggregator

Request to reduce demand

Light load (Load<Gen.) Adjustability producer

DR

PV Aggregator

Energy producer

Heavy load (Load>Gen.)

PV

PV

DR(Increase demand) Demand

Demand

33

BEMS Bldg.1 Incentive payment

DR Aggregator

DR event signal

DR DR DR DR DR

1 2 3 4

5

Peak cut command

DR Command to MEMS

Bldg.2

BEMS Bldg.3

DR 4 DR

Battery Aggregator (Charging/Discharging adjustment)

EV/PHV Aggregator

(Charging time, Load control)

Private power generation aggregator

(Suppressing Buy/Sell Electricity)

DR 1 Building1 Consumption

Time

DR 2 Building2 Consumption

Time

DR 3

Building3 Consumption

Time

5

MEMS Air Conditioning AggregatorSavings (Remote control, Demand restraint)

Demand

DR 1 DR 2 DR 3 BEMS Savings

BEMS

MEMS Mansions1

Consumption

DR contract

DR 4 Mansions1 Consumption

Time

MEMS Mansions2

Consumption

Retail operator Network operator

DR Command to BEMS

Consumption Consumption Consumption

DR Aggregation By DR Aggregator with EMS

DR

5

Mansions2 Consumption

34 Time

34

Toward Cooperation of DER with Bulk Grid  Cooperative control

“connected”

“integrated”

contribution to maintaining electricity quality  Integration of DER : e.g. demand, PV, EV/PHV, battery  size (capacity) & the number

 matching with existing resources  local control (optimization), cooperation with xEMS  communication media and protocol

- grid level vs consumer level - existing system

- international standard Copyright ©2015 Waseda University. All Right Reserved

35

Toward Cooperation of DER with Bulk Grid  System Architecture  Grid operation (e.g. frequency, voltage) and services to

consumers  Requirement from grid operation

transfer as a function

 xEMS as an interface and a control center for devices

- utilization of existing protocols, e.g. E-L, SEP2.0, BACnet - expansion to realize the requirements from grid  Increasing role of “aggregators”

 Smart Inverter : IEC 61850-90-7, IEEE 1547  Various functions : realized by parameters setting

changeable by telecommunication Increase in flexibility of DER Copyright ©2015 Waseda University. All Right Reserved

36

Thank you for your attention.

[email protected]

Copyright ©2015 Waseda University. All Right Reserved

37

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