Approximation Algorithms for Open Shop Variations Subject to Energy Consumption

We consider the open shop scheduling problem subject to speed scaling and energy consumption. The computational complexity is analyzed and approaches to solving various versions of the problem are proposed. The algorithms use a two-stage scheduling scheme. At the first stage, bounds on the objective...

Celý popis

Uložené v:
Podrobná bibliografia
Vydané v:Proceedings of the Steklov Institute of Mathematics Ročník 327; číslo Suppl 1; s. S286 - S301
Hlavný autor: Zakharova, Yu. V.
Médium: Journal Article
Jazyk:English
Vydavateľské údaje: Moscow Pleiades Publishing 01.12.2024
Predmet:
ISSN:0081-5438, 1531-8605
On-line prístup:Získať plný text
Tagy: Pridať tag
Žiadne tagy, Buďte prvý, kto otaguje tento záznam!
Abstract We consider the open shop scheduling problem subject to speed scaling and energy consumption. The computational complexity is analyzed and approaches to solving various versions of the problem are proposed. The algorithms use a two-stage scheduling scheme. At the first stage, bounds on the objective function and processing times of jobs are constructed. At the second stage, the speed scaling problem is reduced to the classical problem with fixed job speeds, and list-type methods are applied for scheduling. As a result, NP-hardness is proved in the general case, and polynomial-time exact and approximation algorithms are proposed for the practically important special cases when preemptions are allowed or not, when the set of speeds is discrete or continuous, and when energy consumption is bounded or optimized. A model of mixed-integer convex programming is constructed based on continuous time representation using the notion of event points.
AbstractList We consider the open shop scheduling problem subject to speed scaling and energy consumption. The computational complexity is analyzed and approaches to solving various versions of the problem are proposed. The algorithms use a two-stage scheduling scheme. At the first stage, bounds on the objective function and processing times of jobs are constructed. At the second stage, the speed scaling problem is reduced to the classical problem with fixed job speeds, and list-type methods are applied for scheduling. As a result, NP-hardness is proved in the general case, and polynomial-time exact and approximation algorithms are proposed for the practically important special cases when preemptions are allowed or not, when the set of speeds is discrete or continuous, and when energy consumption is bounded or optimized. A model of mixed-integer convex programming is constructed based on continuous time representation using the notion of event points.
Author Zakharova, Yu. V.
Author_xml – sequence: 1
  givenname: Yu. V.
  surname: Zakharova
  fullname: Zakharova, Yu. V.
  email: yzakharova@ofim.oscsbras.ru
  organization: Omsk Department of the Sobolev Institute of Mathematics, Siberian Branch of the Russian Academy of Sciences, Dostoevsky Omsk State University
BookMark eNp9kM1OwzAQhC1UJNLCA3DzCwS8jh3XxygqUKlSDwWuUX42aaLWjuxEom9PQrkhcVppZ77V7CzJwliDhDwCewKIxPOBsTVIEa25YIpxiG9IADKCcB0zuSDBLIezfkeW3neMCamEDsg-6Xtnv9pzPrTW0OTUWNcOx7OntXV036Ohh6Pt6Wfu2h-Lp4ex6LAc6GDpxqBrLjSd1uO5n-V7clvnJ48Pv3NFPl427-lbuNu_btNkF5Zc8CEsCq1zFTOosSo4iFohyqqCSuYlU6LScRHrUnKhSq4xklP6giNCrDjnNdPRisD1bums9w7rrHfTE-6SAcvmRrI_jUwMvzJ-8poGXdbZ0Zkp5j_QNwI9ZQM
Cites_doi 10.1002/nav.20133
10.1287/opre.45.4.544
10.1007/978-3-030-91025-9
10.1016/j.ejor.2004.12.008
10.6028/JRES.069B.013
10.1007/s10951-021-00694-7
10.1145/321978.321985
10.1007/s10898-021-01115-x
10.1007/978-3-319-91578-4
10.1016/j.cam.2024.116254
10.1080/00207540701450013
10.1016/j.ejor.2015.08.064
10.1007/s10922-017-9425-0
10.1007/978-94-009-7801-0_9
10.1007/978-3-642-78240-4
10.1137/S009753979222676X
10.1007/978-3-319-44914-2_25
10.1007/s10951-013-0356-7
10.1007/s10951-015-0463-8
10.1007/s10878-020-00591-3
10.1007/s00170-015-7987
10.1145/1982185.1982326
10.1007/s11227-010-0416-0
10.1016/B978-0-444-87358-3.50012-2
10.1007/s10951-020-00653-8
10.1016/j.asoc.2022.108459
10.1016/j.cor.2023.106212
10.3390/pr7060357
10.1145/2612669.2612672
ContentType Journal Article
Copyright Pleiades Publishing, Ltd. 2024
Copyright_xml – notice: Pleiades Publishing, Ltd. 2024
DBID AAYXX
CITATION
DOI 10.1134/S0081543824070216
DatabaseName CrossRef
DatabaseTitle CrossRef
DatabaseTitleList
DeliveryMethod fulltext_linktorsrc
Discipline Mathematics
EISSN 1531-8605
EndPage S301
ExternalDocumentID 10_1134_S0081543824070216
GroupedDBID -Y2
-~X
.VR
06D
0R~
0VY
123
1N0
29P
2J2
2JN
2JY
2KG
2KM
2LR
2VQ
2~H
30V
4.4
408
40D
40E
5VS
6NX
78A
8TC
8UJ
95-
95.
95~
96X
AAAVM
AABHQ
AACDK
AAHNG
AAIAL
AAJBT
AAJKR
AANZL
AAPKM
AARHV
AARTL
AASML
AATNV
AATVU
AAUYE
AAWCG
AAYIU
AAYQN
AAYTO
AAYZH
ABAKF
ABBBX
ABDBE
ABDZT
ABECU
ABFTV
ABHLI
ABHQN
ABJNI
ABJOX
ABKCH
ABKTR
ABMNI
ABMQK
ABNWP
ABQBU
ABQSL
ABSXP
ABTEG
ABTHY
ABTKH
ABTMW
ABULA
ABWNU
ABXPI
ACAOD
ACBXY
ACDTI
ACGFO
ACGFS
ACHSB
ACHXU
ACIWK
ACKNC
ACMDZ
ACMLO
ACOKC
ACOMO
ACPIV
ACREN
ACZOJ
ADHHG
ADHIR
ADKNI
ADKPE
ADRFC
ADTPH
ADURQ
ADYFF
ADYOE
ADZKW
AEBTG
AEFQL
AEGAL
AEGNC
AEJHL
AEJRE
AEKMD
AEMSY
AENEX
AEOHA
AEPYU
AETLH
AEVLU
AEXYK
AFBBN
AFFNX
AFGCZ
AFLOW
AFQWF
AFWTZ
AFYQB
AFZKB
AGAYW
AGDGC
AGJBK
AGMZJ
AGQMX
AGRTI
AGWIL
AGWZB
AGYKE
AHAVH
AHBYD
AHKAY
AHSBF
AHYZX
AIAKS
AIGIU
AIIXL
AILAN
AITGF
AJBLW
AJRNO
ALMA_UNASSIGNED_HOLDINGS
ALWAN
AMKLP
AMTXH
AMXSW
AMYLF
AMYQR
AOCGG
ARMRJ
ASPBG
AVWKF
AXYYD
AZFZN
B-.
BA0
BAPOH
BDATZ
BGNMA
BSONS
CAG
COF
CS3
CSCUP
DDRTE
DNIVK
DPUIP
DU5
EBLON
EBS
EIOEI
EJD
ESBYG
FEDTE
FERAY
FFXSO
FIGPU
FINBP
FNLPD
FRRFC
FSGXE
FWDCC
GGCAI
GGRSB
GJIRD
GNWQR
GQ7
H13
HF~
HG6
HLICF
HMJXF
HRMNR
HVGLF
HZ~
IJ-
IKXTQ
ITM
IWAJR
IXC
I~X
I~Z
J-C
JBSCW
JZLTJ
KOV
LLZTM
M4Y
MA-
N2Q
NB0
NPVJJ
NQJWS
NU0
O9-
O93
O9J
P2P
P9R
PF0
PT4
QOS
R89
R9I
RIG
RNS
ROL
RSV
S16
S1Z
S27
S3B
SAP
SDH
SHX
SISQX
SJYHP
SMT
SNE
SNPRN
SNX
SOHCF
SOJ
SPISZ
SRMVM
SSLCW
STPWE
SZN
T13
TSG
TUC
UG4
UOJIU
UTJUX
UZXMN
VC2
VFIZW
W23
W48
WH7
WK8
YLTOR
YNT
ZMTXR
~A9
AAYXX
ABFSG
ABRTQ
ACSTC
ADHKG
AEZWR
AFDZB
AFHIU
AFOHR
AGQPQ
AHPBZ
AHWEU
AIXLP
ATHPR
CITATION
ID FETCH-LOGICAL-c242t-bb99a7601fedb214f7ee5dd1d5ac074d96b69c5247c29e35081b2ee167222f093
IEDL.DBID RSV
ISICitedReferencesCount 0
ISICitedReferencesURI http://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=Summon&SrcAuth=ProQuest&DestLinkType=CitingArticles&DestApp=WOS_CPL&KeyUT=001447279100012&url=https%3A%2F%2Fcvtisr.summon.serialssolutions.com%2F%23%21%2Fsearch%3Fho%3Df%26include.ft.matches%3Dt%26l%3Dnull%26q%3D
ISSN 0081-5438
IngestDate Sat Nov 29 08:12:39 EST 2025
Tue Mar 11 01:10:37 EDT 2025
IsPeerReviewed true
IsScholarly true
Issue Suppl 1
Keywords NP-hardness
schedule
open shop
algorithm
Language English
LinkModel DirectLink
MergedId FETCHMERGED-LOGICAL-c242t-bb99a7601fedb214f7ee5dd1d5ac074d96b69c5247c29e35081b2ee167222f093
ParticipantIDs crossref_primary_10_1134_S0081543824070216
springer_journals_10_1134_S0081543824070216
PublicationCentury 2000
PublicationDate 20241200
2024-12-00
PublicationDateYYYYMMDD 2024-12-01
PublicationDate_xml – month: 12
  year: 2024
  text: 20241200
PublicationDecade 2020
PublicationPlace Moscow
PublicationPlace_xml – name: Moscow
PublicationTitle Proceedings of the Steklov Institute of Mathematics
PublicationTitleAbbrev Proc. Steklov Inst. Math
PublicationYear 2024
Publisher Pleiades Publishing
Publisher_xml – name: Pleiades Publishing
References M Gao (8500_CR18) 2019; 7
SA Mansouri (8500_CR20) 2016; 248
MA Salido (8500_CR22) 2016; 85
Z Adak (8500_CR9) 2020; 40
D Shabtay (8500_CR8) 2006; 53
LJ He (8500_CR21) 2022; 118
MR Garey (8500_CR26) 1979
W Kubiak (8500_CR1) 2022
Dde Werra (8500_CR31) 1989
I Barany (8500_CR4) 1982; 15
Yu Zakharova (8500_CR16) 2024; 0
KS Kunz (8500_CR34) 1957
AJ Soper (8500_CR32) 2013; 18
A Kononov (8500_CR25) 2016
K Li (8500_CR15) 2020; 60
T Gonzalez (8500_CR3) 1976; 23
ME T. Gerards (8500_CR10) 2016; 19
DB Shmoys (8500_CR29) 1994; 23
E Bampis (8500_CR7) 2014; 0
A Kononov (8500_CR12) 2020; 23
M Pinedo (8500_CR30) 1982
J Edmonds (8500_CR36) 1965; 69B
S Boyd (8500_CR28) 2009
D Li (8500_CR11) 2012
AP Khramova (8500_CR33) 2021; 24
F Kong (8500_CR17) 2011; 0
G Mouzon (8500_CR19) 2007; 45
VS Tanaev (8500_CR2) 1989
B Jurisch (8500_CR5) 1997; 45
A Kononov (8500_CR13) 2022; 83
Y Nesterov (8500_CR27) 2018
D Shabtay (8500_CR6) 2006; 173
A Kononov (8500_CR14) 2023; 21
ASathya Sofia (8500_CR24) 2018; 26
R Stewart (8500_CR23) 2023; 85
M Grotschel (8500_CR35) 1993
References_xml – volume: 53
  start-page: 204
  issue: 3
  year: 2006
  ident: 8500_CR8
  publication-title: Naval Res. Logistics
  doi: 10.1002/nav.20133
– volume: 45
  start-page: 544
  issue: 4
  year: 1997
  ident: 8500_CR5
  publication-title: Oper. Res.
  doi: 10.1287/opre.45.4.544
– volume-title: A Book of Open Shop Scheduling
  year: 2022
  ident: 8500_CR1
  doi: 10.1007/978-3-030-91025-9
– volume: 173
  start-page: 92
  issue: 1
  year: 2006
  ident: 8500_CR6
  publication-title: European J. Oper. Res.
  doi: 10.1016/j.ejor.2004.12.008
– volume: 69B
  start-page: 125
  issue: 1-2
  year: 1965
  ident: 8500_CR36
  publication-title: J. Res. Nat. Bur. Standards
  doi: 10.6028/JRES.069B.013
– volume: 24
  start-page: 405
  issue: 4
  year: 2021
  ident: 8500_CR33
  publication-title: J. Sched.
  doi: 10.1007/s10951-021-00694-7
– volume-title: Energy-Aware Scheduling on Multiprocessor Platforms
  year: 2012
  ident: 8500_CR11
– volume-title: Scheduling Theory, Multi-Stage Systems
  year: 1989
  ident: 8500_CR2
– volume-title: Convex Optimization
  year: 2009
  ident: 8500_CR28
– volume: 21
  start-page: 109
  issue: 2
  year: 2023
  ident: 8500_CR14
  publication-title: Inter. J. Artif. Intel.
– volume-title: Computers and Intractability: A Guide to the Theory of NP-Completeness
  year: 1979
  ident: 8500_CR26
– volume: 23
  start-page: 665
  issue: 4
  year: 1976
  ident: 8500_CR3
  publication-title: J. ACM
  doi: 10.1145/321978.321985
– volume: 83
  start-page: 539
  year: 2022
  ident: 8500_CR13
  publication-title: J. Glob. Optim.
  doi: 10.1007/s10898-021-01115-x
– volume-title: Lectures on Convex Optimization
  year: 2018
  ident: 8500_CR27
  doi: 10.1007/978-3-319-91578-4
– volume: 0
  year: 2024
  ident: 8500_CR16
  publication-title: J. Comput. Appl. Math.
  doi: 10.1016/j.cam.2024.116254
– volume: 45
  start-page: 4247
  year: 2007
  ident: 8500_CR19
  publication-title: Inter. J. Prod. Res.
  doi: 10.1080/00207540701450013
– volume: 248
  start-page: 772
  issue: 3
  year: 2016
  ident: 8500_CR20
  publication-title: European J. Oper. Res.
  doi: 10.1016/j.ejor.2015.08.064
– volume: 26
  start-page: 463
  year: 2018
  ident: 8500_CR24
  publication-title: J. Netw. Syst. Manag.
  doi: 10.1007/s10922-017-9425-0
– volume-title: Deterministic and Stochastic Scheduling: Proceedings of the NATO Advanced Study and Research Institute on Theoretical Approaches to Scheduling Problems, Durham, England, 1981
  year: 1982
  ident: 8500_CR30
  doi: 10.1007/978-94-009-7801-0_9
– volume-title: Geometric Algorithms and Combinatorial Optimization
  year: 1993
  ident: 8500_CR35
  doi: 10.1007/978-3-642-78240-4
– volume: 23
  start-page: 617
  issue: 3
  year: 1994
  ident: 8500_CR29
  publication-title: SIAM J. Comp.
  doi: 10.1137/S009753979222676X
– volume-title: Proceedings of the 9th International Conference on Discrete Optimization and Operations Research, Vladivostok, Russia, 2016
  year: 2016
  ident: 8500_CR25
  doi: 10.1007/978-3-319-44914-2_25
– volume: 18
  start-page: 311
  issue: 3
  year: 2013
  ident: 8500_CR32
  publication-title: J. Sched.
  doi: 10.1007/s10951-013-0356-7
– volume: 19
  start-page: 3
  year: 2016
  ident: 8500_CR10
  publication-title: J. Scheduling
  doi: 10.1007/s10951-015-0463-8
– volume: 40
  start-page: 547
  year: 2020
  ident: 8500_CR9
  publication-title: J. Comb. Optim.
  doi: 10.1007/s10878-020-00591-3
– volume: 15
  start-page: 177
  year: 1982
  ident: 8500_CR4
  publication-title: Szigma Mat. Kozgazd. Fol.
– volume: 85
  start-page: 1303
  year: 2016
  ident: 8500_CR22
  publication-title: Inter. J. Adv. Manufact. Techn.
  doi: 10.1007/s00170-015-7987
– volume: 0
  start-page: 635
  year: 2011
  ident: 8500_CR17
  publication-title: Proceedings of the ACM Symposium on Applied Computing, New York, USA, 2011
  doi: 10.1145/1982185.1982326
– volume: 60
  start-page: 223
  year: 2020
  ident: 8500_CR15
  publication-title: J. Supercomput.
  doi: 10.1007/s11227-010-0416-0
– volume-title: Numerical Analysis
  year: 1957
  ident: 8500_CR34
– volume-title: Advances in Project Scheduling
  year: 1989
  ident: 8500_CR31
  doi: 10.1016/B978-0-444-87358-3.50012-2
– volume: 23
  start-page: 693
  issue: 6
  year: 2020
  ident: 8500_CR12
  publication-title: J. Scheduling
  doi: 10.1007/s10951-020-00653-8
– volume: 118
  year: 2022
  ident: 8500_CR21
  publication-title: Appl. Soft Comput.
  doi: 10.1016/j.asoc.2022.108459
– volume: 85
  year: 2023
  ident: 8500_CR23
  publication-title: Comp. Oper. Res.
  doi: 10.1016/j.cor.2023.106212
– volume: 7
  start-page: 357
  issue: 6
  year: 2019
  ident: 8500_CR18
  publication-title: Processes
  doi: 10.3390/pr7060357
– volume: 0
  start-page: 138
  year: 2014
  ident: 8500_CR7
  publication-title: Proceedings of the 26th ACM Symposium on Parallelism in Algorithms and Architectures, Prague, Czech Republic, 2014
  doi: 10.1145/2612669.2612672
SSID ssj0045749
Score 2.3059762
Snippet We consider the open shop scheduling problem subject to speed scaling and energy consumption. The computational complexity is analyzed and approaches to...
SourceID crossref
springer
SourceType Index Database
Publisher
StartPage S286
SubjectTerms Mathematics
Mathematics and Statistics
Title Approximation Algorithms for Open Shop Variations Subject to Energy Consumption
URI https://link.springer.com/article/10.1134/S0081543824070216
Volume 327
WOSCitedRecordID wos001447279100012&url=https%3A%2F%2Fcvtisr.summon.serialssolutions.com%2F%23%21%2Fsearch%3Fho%3Df%26include.ft.matches%3Dt%26l%3Dnull%26q%3D
hasFullText 1
inHoldings 1
isFullTextHit
isPrint
journalDatabaseRights – providerCode: PRVAVX
  databaseName: SpringerLINK Contemporary 1997-Present
  customDbUrl:
  eissn: 1531-8605
  dateEnd: 99991231
  omitProxy: false
  ssIdentifier: ssj0045749
  issn: 0081-5438
  databaseCode: RSV
  dateStart: 20060101
  isFulltext: true
  titleUrlDefault: https://link.springer.com/search?facet-content-type=%22Journal%22
  providerName: Springer Nature
link http://cvtisr.summon.serialssolutions.com/2.0.0/link/0/eLvHCXMwnV1LSwMxEA5aPejBt1hf5OBJCbh5bo6ltHixitXS27LJJrag3dJdxZ9vkt0VinrQ-7AsQzLfN5n5ZgC4IEKkUmOBUs4soipSyMGwQMJiYSlWDDMblk2IwSAej-V9reMumm73piQZInW1d4QGTa_DexL7HMQhE18Faw7tYn8bH4ajJvxSJmrOG0fIm9elzB8_sQxGy5XQADD97X_92g7Yqvkk7FQHYBesmNke2Lz9GsZa7IO7jp8b_jGtRIqw8_KcL6bl5LWAjrBC31ECh5N8Dkcuba7e76ALJ_59BpY57AVxIOwGqWaILwfgqd977N6geo8C0g6AS6SUlKnvfbEmUziiVhjDsizKWKodg8gkV1xqhqnQWBriKFuksDERF4482GtJDkFrls_MEYCKKOv8m2KuOWVpFnNiMkO1kjExEVVtcNk4NJlX4zKSkGYQmnzzUhtcNe5M6ptT_G59_CfrE7CBHf2oGk9OQatcvJkzsK7fy2mxOA8n5hO-2bld
linkProvider Springer Nature
linkToHtml http://cvtisr.summon.serialssolutions.com/2.0.0/link/0/eLvHCXMwnV1LS8NAEF60CurBt1ife_CkBMw-s8dSKhXbKraW3kJ2s2sL2pQmij_fzSYRinrQ-7CEYTPfNzvfzABwgTmPhELcixg1HpG-9CwMc48bxA1BkiJq3LIJ3usFo5F4KPu400rtXpUkXaQu9o4Q19Nr8R4HeQ5ikYktgxViASvX8T32h1X4JZSXnDfwvdy8LGX-eMQiGC1WQh3A3Gz969O2wWbJJ2GjuAA7YElPd8FG92sYa7oH7hv53PCPSdGkCBsvz8l8ko1fU2gJK8wVJbA_TmZwaNPm4v0O2nCSv8_ALIEt1xwIm65V08WXffB00xo02165R8FTFoAzT0oholz7YnQskU8M15rGsR_TSFkGEQsmmVAUEa6Q0NhSNl8irX3GLXkw1wIfgNo0mepDACWWxvo3QkwxQqM4YFjHmigpAqx9IuvgsnJoOCvGZYQuzcAk_OalOriq3BmWf076u_XRn6zPwVp70O2Endve3TFYR5aKFCKUE1DL5m_6FKyq92ySzs_c7fkEenW8QQ
linkToPdf http://cvtisr.summon.serialssolutions.com/2.0.0/link/0/eLvHCXMwpV1bS8MwFA46RfTBuzivefBJKdpcm8cxNxR1DqbDt9K0iRtoO9Yq_nyTtBWG-iC-H0I5pOf7Ts7lA-AEcx6JGHEvYlR7RPrSMzDMPa4R1wRJiqh2YhO81wuenkS_0jnN6273uiRZzjTYLU1pcT5JdKVBQtx8r8F-HNh8xKAUmwcLxGoG2XR9MKxDMaG84r-B71nzqqz54xGzwDRbFXVg013792eug9WKZ8JWeTE2wJxKN8HK3deS1nwL3LfsPvGPcTm8CFsvz9l0XIxec2iILLSdJnAwyiZwaNLp8l0PmjBj321gkcGOGxqEbTfC6eLONnjsdh7aV16lr-DFBpgLT0ohItsTo1UikU80V4omiZ_QKDbMIhFMMhFTRHiMhMKGyvkSKeUzbkiFvhB4BzTSLFW7AEostfF1hFjMCI2SgGGVKBJLEWDlE9kEp7Vzw0m5RiN06Qcm4TcvNcFZ7dqw-qPy3633_mR9DJb6l93w9rp3sw-WkWEoZW_KAWgU0zd1CBbj92KcT4_cRfoEN7fFJQ
openUrl ctx_ver=Z39.88-2004&ctx_enc=info%3Aofi%2Fenc%3AUTF-8&rfr_id=info%3Asid%2Fsummon.serialssolutions.com&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Approximation+Algorithms+for+Open+Shop+Variations+Subject+to+Energy+Consumption&rft.jtitle=Proceedings+of+the+Steklov+Institute+of+Mathematics&rft.au=Zakharova%2C+Yu.+V.&rft.date=2024-12-01&rft.pub=Pleiades+Publishing&rft.issn=0081-5438&rft.eissn=1531-8605&rft.volume=327&rft.issue=Suppl+1&rft.spage=S286&rft.epage=S301&rft_id=info:doi/10.1134%2FS0081543824070216&rft.externalDocID=10_1134_S0081543824070216
thumbnail_l http://covers-cdn.summon.serialssolutions.com/index.aspx?isbn=/lc.gif&issn=0081-5438&client=summon
thumbnail_m http://covers-cdn.summon.serialssolutions.com/index.aspx?isbn=/mc.gif&issn=0081-5438&client=summon
thumbnail_s http://covers-cdn.summon.serialssolutions.com/index.aspx?isbn=/sc.gif&issn=0081-5438&client=summon