Z. Yi, T. Dohi and H. Okamura, Survivability quantification of wireless ad hoc network taking account of border effects, Proceedings of the 21st IEEE Pacific Rim International Symposium on Dependable Computing (PRDC 2015), pp. 149-158, IEEE CPS, 2015.

H. Okamura and T. Dohi, Towards comprehensive software reliability evaluation in open source software, Proceedings of the 24th International Symposium on Software Reliability Engineering (ISSRE 2015), pp. 121-129, IEEE CPS, 2015.

H. Okamura and T. Dohi, mapfit: An R-based tool for PH/MAP parameter estimation, The 14th International Conference on Quantitative Evaluation of Systems (QEST2015) (J. Campos and B. R. Haverkort, eds.), Lecture Notes in Computer Science, vol. 9295, pp. 105-112, Springer-Verlag, 2015.

H. Okamura, S. Miyata and T. Dohi, Optimal power-aware design in a cluster system: Markov decision process approach, Proceedings of the 12th IEEE International Conference on Advanced and Trusted Computing (ATC 2015), pp. 527-532, IEEE CPS, 2015.

H. Okamura, Y. Takekoshi and T. Dohi, Fine-grained software reliability estimation using software testing inputs, Proceedings of 2015 IEEE International Conference on Software Quality, Reliability and Security (QRS 2015), pp. 85-92, IEEE CPS, 2015.

H. Okamura, M. Gong and T. Dohi, A note on optimal allocation of testing-resources with architecture-based software reliability model, Proceedings of 2015 International Conference on Quality, Reliability, Risk, Maintenance, and Safety Engineering (QR2MSE 2015), vol. I, pp. 8-13, 2015.

H. Okamura and T. Dohi, A note on variational Bayes approach for software reliability growth model with normal distribution, Proceedings of the 9th International Conference on Mathematical Methods in Reliability, Theory, Methods and Applications (MMR-2015), pp. 41-48, 2015.

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T. Koga, T. Dohi and H. Okamura, Optimal reliability design for real-time systems with dynamic voltage and frequency scaling, Proceedings of The 20th IEEE Pacific Rim International Symposium on Dependable Computing (PRDC 2014), pp. 213-222, IEEE CPS, 2014.

H. Okamura, Y. Kunomoto and T. Dohi, Coarse-grained parallel uniformization for continuous-time Markov chains, Proceedings of The 20th IEEE Pacific Rim International Symposium on Dependable Computing (PRDC 2014), pp. 116-124, IEEE CPS, 2014.

C. Luo, H. Okamura and T. Dohi, Optimized patch applying schedule within multiplex software architecture, Proceedings of The 6th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2014), pp. 311-318, McGraw-Hill, Taiwan, 2014.

H. Okamura, Y. Takekoshi and T. Dohi, Fine-grained software reliability estimation using software testing inputs, Proceedings of The 6th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2014), pp. 365-372, McGraw-Hill, Taiwan, 2014.

H. Okamura and T. Dohi, Maximum penalized likelihood estimation for phase-type software reliability growth model, Proceedings of The 6th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2014), pp. 373-380, McGraw-Hill, Taiwan, 2014.

H. Okamura, J. Guan, C. Luo and T. Dohi, Quantifying resiliency of virtualized system with software rejuvenation, Proceedings of The 2014 International Conference on Quality, Reliability, Risk, Maintenance, and Safety Engineering (QR2MSE 2014), 6 pages, 2014.

H. Okamura and T. Dohi, A novel framework of software reliability evaluation with software reliability growth models and software metrics, Proceedings of The 15th IEEE International Symposium on High Assurance Systems Engineering (HASE 2014), pp. 97-104, IEEE CPS, 2014.

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H. Okamura, C. Luo and T. Dohi, Estimating response time distribution of server application in software aging phenomenon, Proceedings of IEEE 5th International Workshop on Software Aging and Rejuvenation (WoSAR-2013), 4 pages, IEEE CPS, 2013.

S. Ikemoto, T. Dohi and H. Okamura, Quantifying software test process and product reliability simultaneously, Proceedings of The 24th International Symposium on Software Reliability Engineering (ISSRE 2013), pp. 108-117, IEEE CPS, 2013.

H. Okamura and T. Dohi, SRATS: Software reliability assessment tool on spreadsheet, Proceedings of The 24th International Symposium on Software Reliability Engineering (ISSRE 2013), pp. 100-117, IEEE CPS, 2013.

S. Ikemoto, T. Dohi and H. Okamura, Estimating software reliability with static project data in incremental development processes, Proceedings of 2013 Joint Conference of the 23rd International Workshop on Software Measurement (IWSM-2013) and the 8th International Conference on Software Process and Product Measurement (MENSURA-2013), pp. 219-224, IEEE CPS, 2013.

C. Luo, H. Okamura and T. Dohi, Modeling and analysis of multi-version concurrent control, Proceedings of The 37th Annual International Computer Software and Applications Conference (COMPSAC 2013), pp. 53-58, IEEE CPS, 2013.

J. Zheng, H. Okamura and T. Dohi, Sensitivity analysis of reliability function for virtualized system, Proceedings of the 8th International Conference on Mathematical Methods in Reliability, -Theory, Methods and Applications - (MMR-2013), pp. 229-232, 2013.

H. Okamura, T. Hirata and T. Dohi, NHPP-based software reliability model with mixed gamma distribution, Advanced Science and Technology Letters, vol. 19, pp. 240--243, SERSC, 2013.

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R. Watanabe, H. Okamura and T. Dohi, An efficient MCMC algorithm for continuous PH distributions, Proceedings of The 2012 Winter Simulation Conference (C. Laroque, J. Himmelspach, R. Pasupathy, O. Rose and A. M. Uhrmacher, eds.), 12 pages, 2012.

H. Okamura and T. Dohi, Optimization of opportunity-based software rejuvenation policy, Proceedings of IEEE 4th International Workshop on Software Aging and Rejuvenation (WoSAR-2012), pp. 283-286, IEEE CPS, 2012.

H. Okamura, M. Tokuzane and T. Dohi, Security evaluation for software system with vulnerability life cycleand user profiles, Proceedings of 2012 Workshop on Dependable Transportation/Recent Advances in Software Dependability (WDTS-RASD 2012), pp. 39-44, IEEE CPS, 2012.

R. Watanabe, H. Okamura and T. Dohi, Variational Bayes for discrete phase-type distributions, Proceedings of 2012 Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2012), pp. 542--549, McGraw-Hill, Taiwan, 2012.

K. Yamamoto, H. Okamura and T. Dohi, Transient analysis of software rejuvenation policies in virtualized system, Proceedings of 2012 Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2012), pp. 574-580, McGraw-Hill, Taiwan, 2012.

H. Okamura and T. Dohi, Application of hierarchical Bayesian modeling to discrete-time software reliability growth model, Proceedings of 2012 Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2012), pp. 382-389, McGraw-Hill, Taiwan, 2012.

Z. Yi, T. Dohi and H. Okamura, Survivability modeling and analysis for a power-aware wireless ad hoc network, Proceedings of 4th International Workshop on Reliable Networks Design and Modeling (RNDM 2012), pp. 813-819, IEEE CPS, 2012.

H. Okamura and T. Dohi (2012) Optimal time-out policy in dynamic power management, Proceedings of the 2nd International Conference on Computer and Management (CAMAN-2012), 916-919, IEEE CPS.

J. Zheng, H. Okamura and T. Dohi (2012), Component importance analysis of virtualized system, Proceedings of 9th IEEE International Conference on Autonomic and Trusted Computing (ATC 2012), 462-469, IEEE CPS.

C. Luo, H. Okamura and T. Dohi (2012), Model-based performance optimization of generalized snapshot isolation in database system, Proceedings of 9th IEEE International Conference on Autonomic and Trusted Computing (ATC 2012), 494-500, IEEE CPS.

T. Dohi, H. Okamura and K. S. Trivedi (2012), Optimizing software rejuvenation policies under interval reliability criteria, Proceedings of 9th IEEE International Conference on Autonomic and Trusted Computing (ATC 2012), 478-485, IEEE CPS.

S. Ukimoto, T. Dohi, and H. Okamura (2012) Software testing-resource allocation with operational profile, Proceedings of 27th ACM Symposium on Applied Computing (SAC-2012), 1203-1208, ACM.

S. Ikemoto, T. Dohi, and H. Okamura (2012) Estimating software reliability via pseudo maximum likelihood method, Proceedings of 27th ACM Symposium on Applied Computing (SAC-2012), 1171-1176, ACM.

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H. Okamura, T. Dohi, and S. Osaki (2011) Bayesian inference for credible intervals of optimal software release time, Advances in Software Engineering and Its Applications (ASEA2011), Communications in Computer and Information Science (CCIS) 257, 377-384, Springer.

H. Okamura and T. Dohi (2011) A POMDP formulation of multistep failure model with software rejuvenation, Proceedings of IEEE 3rd International Workshop on Software Aging and Rejuvenation (WoSAR-2011), 14-19, IEEE CPS.

K. Okumura, H. Okamura, and T. Dohi (2011) On the effect of the order of test cases in the modified exponential software reliability growth model, Proceedings of 2011 Second International Conference on Networking and Computing (ICNC-2011), 294-296, IEEE CPS.

H. Okamura, T. Dohi, and S. Osaki (2011) Software reliability growth model with normal distribution and its parameter estimation, Proceedings of the International Conference on Quality, Reliability, Maintenance and Safety Engineering (ICQR2MSE 2011), 424-429, IEEE CPS.

H. Okamura and T. Dohi (2011) Unification of software reliability models using Markovian arrival processes, Proceedings of 17th IEEE Pacific Rim International Symposium on Dependable Computing (PRDC-2011), 20-27, IEEE CPS.

H. Okamura, Y. Etani, and T. Dohi (2011) Quantifying the effectiveness of testing efforts on software fault detection with a logit software reliability growth model, Proceedings of 2011 Joint Conference of the 21st International Workshop on Software Measurement and the 6th International Conference on Software Process and Product Measurement (IWSM/MENSURA-2011), 62-68, IEEE CPS.

H. Okamura, T. Dohi, S. Shiraishi, and M. Abe (2011) Composite dependability modeling for in-vehicle networks, Supplemental Proceedings of the 41st Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN-2011), 240-245, IEEE CPS.

H. Okamura and T. Dohi (2011) Application of reinforcement learning to software rejuvenation, Proceedings of the 10th International Symposium on Autonomous Decentralized Systems (ISADS-2011), 647-652, IEEE CPS.

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H. Okamura, T. Dohi, and K. S. Trivedi (2010) An improvement of EM algorithm for PH distributions with group data, Proceedings of 4th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2010), 532-539, McGraw-Hill.

H. Okamura, T. Dohi, and S. Osaki (2010) A dynamic programming approach for sequential preventive maintenance policies, Proceedings of 4th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2010), 540-547, McGraw-Hill.

T. Dohi, H. Okamura, and K. S. Trivedi (2010) Comparing software cost rate models with rejuvenation, Proceedings of 4th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2010), 161-168, McGraw-Hill.

T. Ishii, T. Dohi, and H. Okamura (2010) Applying least squares estimation to software reliability prediction, Proceedings of 4th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2010), 241-248, McGraw-Hill.

T. Dohi, H. Okamura, and S. Osaki (2010) Transient analysis of software availability models with rejuvenation, Proceedings of 4th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2010), 169-176, McGraw-Hill.

K. Yamana, H. Okamura, and T. Dohi (2010) A note on quasi-Monte Carlo simulation for non-homogeneous Markov chains, Proceedings of 4th Asia-Pacific International Symposium on Advanced Reliability and Maintenance Modeling (APARM 2010), 780-787, McGraw-Hill.

H. Okamura and T. Dohi (2010) Performance-aware software rejuvenation strategies in a queueing system, Supplemental Proceedings of 21st International Symposium on Software Reliability Engineering (ISSRE2010), 6 pages.

S. Hiroyama, T. Dohi, and H. Okamura (2010) Comparison of aperiodic checkpoint placement algorithms, Advanced Computer Science and Information Technology (AST2010), Communications in Computer and Information Science (CCIS) 74, 145-156, Springer.

H. Okamura and T. Dohi (2010) Estimating computer virus propagation based on Markovian arrival processes, Proceedings of 16th Pacific Rim International Symposium on Dependable Computing (PRDC 2010), 199-206, IEEE Computer Society Press.

T. Fujii, T. Dohi, H. Okamura, and T. Fujiwara (2010) A software accelerated life testing model, Proceedings of 16th Pacific Rim International Symposium on Dependable Computing (PRDC 2010), 85-92, IEEE Computer Society Press.

H. Okamura, Y. Etani, and T. Dohi (2010) A multi-factor software reliability model based on logistic regression, Proceedings of 21st International Symposium on Software Reliability Engineering (ISSRE2010), 31-40, IEEE Computer Society Press.

H. Okamura, T. Dohi, and K. S. Trivedi (2010) On-line adaptive algorithms in autonomic restart control, Proceedings of 7th International Conference on Autonomic and Trusted Computing (ATC2010), Lecture Notes in Computer Science (LNCS) 6407, 32-46, Springer.

H. Okamura, H. Kishikawa, and T. Dohi (2010) Application of deterministic annealing EM algorithm to Markovian arrival parameter estimation, Proceedings of 2010 Symposia and Workshop on Ubiquitous, Autonomic and Trusted Computing (UIC-ATC 2010), 352-357, IEEE Computer Society Press.

B. Zhou, H. Okamura, and T. Dohi (2010) Markov chain Monte Carlo random testing, Advanced Computer Science and Information Technology (AST/UCMA/ISA/ACN 2010), Lecture Notes in Computer Science (LNCS) 6059, 447-456, Springer.

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H. Okamura and T. Dohi (2009) An EM algorithm for record value statistics models in software reliability estimation, Advances in Software Engineering and Its Applications (ASEA2009), Communications in Computer and Information Science (CCIS) 59, 288-295, Springer.

R. Fujimoto, H. Okamura, and T. Dohi (2009) Security evaluation of an intrusion tolerant system with MRSPNs, Proceedings of 4th International Conference on Availability, Reliability and Security (ARES 2009), 427-432, IEEE Computer Society Press.

H. Okamura and T. Dohi (2009) A Bayesian inference tool for NHPP-based software reliability assessment, Future Generation Information Technology 2009 (FGIT2009), Lecture Notes in Computer Science (LNCS) 5899, 226-237, Springer.

H. Okamura, M. Tokuzane, and T. Dohi (2009) Optimal security patch release timing under non-homogeneous vulnerability-discovery processes, Proceedings of 20th International Symposium on Software Reliability Engineering (ISSRE'09), 120-128, IEEE Computer Society Press.

H. Okamura and T. Dohi (2009) Faster maximum likelihood estimation algorithms for Markovian arrival processes, Proceedings of 6th International Conference on Quantitative Evaluation of Systems (QEST2009), 73-82, IEEE Computer Society Press.

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H. Okamura and T. Dohi (2008) A repair-limit replacement policy with retry, Proceedings of 2008 Asian International Workshop on Advanced Reliability Modeling (AIWARM2008), 289-296, McGraw-Hill.

Y. Yamaguchi, H. Okamura, and T. Dohi (2008) Estimating a mixture of Erlang distributions based on variational Bayes, Proceedings of 2008 Asian International Workshop on Advanced Reliability Modeling (AIWARM2008), 619-626, McGraw-Hill.

H. Okamura and T. Dohi (2008) Hyper-Erlang software reliability model, Proceedings of 14th Pacific Rim International Symposium on Dependable Computing (PRDC'08), 232-239, IEEE Computer Society Press.

H. Okamura and T. Dohi (2008) Availability optimization in operational software system with aperiodic time-based rejuvenation scheme, Supplemental Proceedings of 19th International Symposium on Software Reliability Engineering (ISSRE'08), 6 pages, IEEE Computer Society Press.

H. Okamura and T. Dohi (2008) Analysis of a software system with rejuvenation, restoration and checkpointing, Service Availability: 5th International Service Availability Symposium (ISAS2008), Lecture Notes in Computer Science (LNCS) 5017, 110-128, Springer.

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H. Okamura, T. Sakoh, and T. Dohi (2007) A note on Markov chain Monte Carlo for software reliability models with group data, Proceedings of 2007 International Workshop on Recent Advances in Stochastic Operations Research (RASOR'07), 221-228.

K. Shibata, K. Rinsaka, T. Dohi, and H. Okamura (2007) Quantifying software maintainability based on a fault-detection/correction model, Proceedings of 13th Pacific Rim International Symposium on Dependable Computing (PRDC'07), 35-42, IEEE Computer Society Press.

H. Okamura, K. Tateishi, and T. Dohi (2007) Statistical inference of computer virus propagation using non-homogeneous Poisson processes, Proceedings of 18th International Symposium on Software Reliability Engineering (ISSRE'07), 149-158, IEEE Computer Society Press.

H. Okamura, Y. Kamahara, and T. Dohi (2007) Estimating Markov-modulated compound Poisson process, Proceedings of 2nd international conference on Performance evaluation methodologies and tools (Valuetools'07).

L. Zhang, H. Okamura, and T. Dohi (2007) Performance evaluation for automatic protection switching in CDMA-TDD wireless communication system, Human-Computer Interaction: 12th International Conference on Human-Computer Interaction (HCI'07) Part IV, Lecture Notes in Computer Science (LNCS) 4553, 1200-1209, Springer.

T. Ishii, T. Dohi, and H. Okamura (2007) Bivariate software fault-detection models, Proceedings of 31st Annual International Computer Software and Applications Conference (COMPSAC2007), 535-538, IEEE Computer Society Press.

H. Okamura, M. Grottke, T. Dohi, and K. S. Trivedi (2007) Variational Bayesian approach for interval estimation of NHPP-based software reliability models, Proceedings of 2007 International Conference on Dependable Systems and Networks (DSN2007), 698-707, IEEE Computer Society Press.

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H. Okamura, T. Sakoh, and T. Dohi (2006) Variational Bayesian approach for exponential software reliability model, Proceedings of 10th IASTED International Conference on Software Engineering and Applications, 82-87, ACTA Press.

H. Gotoh, H. Okamura, and T. Dohi (2006) A note on parameter estimation for phase-type distribution in canonical form, Proceedings of 2006 Asian International Workshop on Advanced Reliability Modeling (AIWARM2006), 577-584, World Scientific.

H. Okamura and T. Dohi (2006) Software reliability modeling based on mixed Poisson distributions, Proceedings of 2006 Asian International Workshop on Advanced Reliability Modeling (AIWARM2006), 427-434, World Scientific.

K. Iwamoto, T. Maruo, H. Okamura, and T. Dohi (2006) Aperiodic optimal checkpoint sequence under steady-state system availability criterion, Proceedings of 2006 Asian International Workshop on Advanced Reliability Modeling (AIWARM2006), 251-258, World Scientific.

K. Tateishi, H. Okamura, and T. Dohi (2006) Transient analysis of Internet-worm propagation based on simple birth-and-death processes, Proceedings of 2006 Asian International Workshop on Advanced Reliability Modeling (AIWARM2006), 676-683, World Scientific.

H. Okamura, H. Furumura, and T. Dohi (2006) On the effect of fault removal in software testing - Bayesian reliability estimation approach, Proceedings of 17th International Symposium on Software Reliability Engineering (ISSRE'06), 247-255, IEEE Computer Society Press.

H. Okamura and T. Dohi (2006) Building phase-type software reliability models, Proceedings of 17th International Symposium on Software Reliability Engineering (ISSRE'06), 289-298, IEEE Computer Society Press.

T. Ando, H. Okamura, and T. Dohi (2006) Estimating Markov modulated software reliability models via EM algorithm, Proceedings of 2nd IEEE International Symposium on Dependable, Autonomic and Secure Computing (DASC'06), 111-118, IEEE Computer Society Press.

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H. Okamura, M. Ito, and T. Dohi (2005) A subordinated Markov chain model for assessing software safety, Proceedings of International Conference on Reliability and Safety Engineering (INCRESE 2005), 363-373.

H. Okamura, K. Iwamoto, and T. Dohi (2005) A DP-based optimal checkpointing algorithm for a real time system, Proceedings of 11th International Conference on Reliability and Quality in Design (ISSAT 2005), 22-26.

H. Okamura, H. Goto, and T. Dohi (2005) EM algorithm for fitting Markovian arrival processes to time-interval sampling data, Proceedings of International Workshop on Recent Advances in Stochastic Operations Research (RASOR 2005), 203-210.

H. Okamura, K. Tsuruta, and T. Dohi (2005) An architecture-based software reliability model with finite number of faults, Proceedings of 9th IASTED International Conference on Software Engineering, 20-25, ACTA Press.

H. Okamura and T. Dohi (2005) Performance evaluation of power-aware communication network devices, Proceedings of 2005 IFIP International Conference on Embedded and Ubiquitous Computing (EUC '05), Lecture Notes in Computer Science (LNCS) 3824, 245-254, Springer.

H. Okamura, H. Kobayashi, and T. Dohi (2005) Markovian modeling and analysis of Internet worm propagation, Proceedings of 16th International Symposium on Software Reliability Engineering (ISSRE'05), 149-158, IEEE Computer Society Press.

H. Okamura, K. Iwamoto, and T. Dohi (2005) A dynamic programming algorithm for software rejuvenation scheduling under distributed computation circumstance, Proceedings of IEEE 11th International Conference on Parallel and Distributed Systems (ICPDS-2005), 493-497, IEEE Computer Society Press.

K. Ohishi, H. Okamura, and T. Dohi (2005) Gompertz software reliability model and its application, Proceedings of 29th Annual International Computer Software and Application Conference (COMPSAC 2005), 405-410, IEEE Computer Society Press.

H. Okamura, S. Miyahara, and T. Dohi (2005) Effect of preventive rejuvenation in communication network system with burst arrival, Proceedings of 7th International Symposium on Autonomous Decentralized Systems (ISADS 2005), 151-158, IEEE Computer Society Press.

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H. Okamura, H. Kobayashi, and T. Dohi (2004) Dependence of computer virus prevalence on network structure - stochastic modeling approach, Proceedings of 2004 Asian International Workshop on Advanced Reliability Modeling (AIWARM2004), 379-386, World Scientific.

H. Okamura, T. Fukuda, and T. Dohi (2004) An improved intrusion-detection model by profiling correlated access data, Proceedings of 2004 Asian International Workshop on Advanced Reliability Modeling (AIWARM2004), 371-378, World Scientific.

H. Okamura, T. Sugihara, T. Dohi, and S. Osaki (2004) Bayesian statistical approach to design the optimal auto-sleep function in a computer system, Proceedings of 47th IEEE International Midwest Symposium on Circuits and Systems, II309-II312, IEEE Circuits and Systems Society.

H. Okamura, T. Dohi, and S. Osaki (2004) EM algorithms for logistic software reliability models, Proceedings of 22nd IASTED International Conference on Software Engineering, 263-268, ACTA Press

T. Ozaki, T. Dohi, H. Okamura, and N. Kaio (2004) Min-max checkpoint placement under incomplete failure information, Proceedings of International Conference on Dependable Systems and Networks (DSN-2004), 721-730, IEEE Computer Society Press.

H. Okamura, Y. Nishimura, and T. Dohi (2004) A dynamic checkpointing scheme based on reinforcement learning, Proceedings of 10th International Symposium on Pacific Rim Dependable Computing (PRDC 2004), 151-158, IEEE CPS.

H. Okamura, A. Murayama, and T. Dohi (2004) EM algorithm for discrete software reliability models: a unified parameter estimation method, Proceedings of 8th IEEE International Symposium on High Assurance Systems Engineering (HASE2004), 219-228, IEEE Computer Society Press.

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H. Okamura, Y. Watanabe, and T. Dohi (2003) An iterative scheme for maximum likelihood estimation in software reliability modeling, Proceedings of 14th International Symposium on Software Reliability Engineering (ISSRE'03), 246-256, IEEE Computer Society Press.

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T. Dohi, H. Okamura, and N. Kaio (2002) Optimal age-dependent checkpoint strategy with retry of rollback recovery, Proceedings of 2nd International Workshop on Autonomous Decentralized System (IWADS2002), 113-118, IEEE Computer Society Press.

H. Okamura, K. Kumada, and T. Dohi (2002) Diffusion approximation for incomplete convolutions arising in multi-stage production/inventory systems, Proceedings of 7th Annual International Conference on Industrial Engineering, 346-349.

H. Fujio, H. Okamura, and T. Dohi (2002) Fine-grained shock models to rejuvenate software system, Proceedings of Second Euro-Japanese Workshop on Stochastic Risk Modelling for Finance, Insurance, Production and Reliability, 111-120.

K. Iwamoto, T. Dohi, H. Okamura, and N. Kaio (2002) Discrete-time cost analysis for a telecommunication billing application with rejuvenation, Proceedings of Second Euro-Japanese Workshop on Stochastic Risk Modelling for Finance, Insurance, Production and Reliability, 181-190.

H. Okamura, K. Iwasaki, T. Dohi, and S. Osaki (2002) A unified approximation of optimal shutdown policy, Proceedings of Second Euro-Japanese Workshop on Stochastic Risk Modelling for Finance, Insurance, Production and Reliability, 396-404.

H. Okamura, T. Sugihara, and T. Dohi (2002) A sequential estimation algorithm for the optimal shutdown policy in a queueing system, Proceedings of 2002 Japan-USA Symposium on Flexible Automation, 1099-1106.

H. Okamura, S. Miyahara, and T. Dohi (2002) Dependability analysis of a client/server software system with rejuvenation, Proceedings of 13th International Symposium on Software Reliability Engineering (ISSRE'02), 171-180, IEEE Computer Society Press.

H. Okamura, Y. Watanabe, and T. Dohi (2002) Estimating a mixed software reliability models based on the EM algorithm, Proceedings of International Symposium on Empirical Software Engineering (ISESE2002), 69-78, IEEE Computer Society Press.

T. Dohi, K. Iwamoto, H. Okamura, and N. Kaio (2002) Discrete availability models to rejuvenate a telecommunication billing application, Proceedings of 7th IEEE International Symposium on High Assurance Systems Engineering (HASE2002), 159-166, IEEE Computer Society Press.

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T. Dohi, T. Danjou, and H. Okamura (2001) Optimal software rejuvenation policy with discounting, Proceedings 2001 Pacific Rim International Symposium on Dependable Computing, 87-94, IEEE Computer Society Press.

H. Okamura, T. Dohi, and S. Osaki (2001) Optimal shutdown schedule for a single-user operating system under a Markovian arrival circumstance, Proceedings of 10th International Symposium on Applied Stochastic Models and Data Analysis, 801-806.

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T. Dohi, H. Okamura, N. Kaio, and S. Osaki (2000) Age-dependent optimal warranty policy and its application to software maintenance contract, Proceedings of 5th International Conference on Probabilistic Safety Assessment and Management, 2547-2552.

H. Okamura, T. Dohi, and S. Osaki (2000) Characterizing the idle-period distribution of a GI/G/1 queue with vacation, Proceedings of 32nd ISCIE International Symposium on Stochastic Systems Theory and Its Applications, 177-182.

H. Okamura, T. Dohi, and S. Osaki (2000) Performance analysis of a transaction based software system with shutdown, Proceedings of 2nd International Workshop on Software and Performance, 168-179, ACM.

T. Dohi, H. Okamura, and S. Osaki (2000) The optimal design of delivery schedule in a continuous-time (r, Q) cyclic inventory system, Proceedings of 2000 Pacific Conference on Manufacturing, 221-226.

H. Okamura, A. Fujimoto, T. Dohi, S. Osaki, and K. S. Trivedi (2000) The optimal preventive maintenance policy for a software system with multi server station, Proceedings of 6th ISSAT International Conference on Reliability and Quality in Design, 275-279.

H. Okamura, T. Dohi, and S. Osaki (2000) A structural approximation method to generate the optimal auto-sleep schedule for a computer system, Proceedings of International Conference on Applied Stochastic System Modeling, 180-187.

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H. Okamura, T. Dohi, N. Kaio, and S. Osaki (1999) The optimal control-limit policies for buffer systems with different recovery functions, Proceedings of 31st ISCIE International Symposium on Stochastic Systems Theory and Its Applications, 55-60.

H. Okamura, K. Hamamoto, T. Dohi, and S. Osaki (1999) The diffusion approximation method for the G/G/1 type of economic manufacturing quantity process with preventive maintenance, Proceedings of Second Asia-Pacific Conference on Industrial Engineering and Management Systems, 141-144.

H. Okamura, T. Dohi, and S. Osaki (1999) The phase type approximation for the optimal auto-sleep scheduling, Proceedings of First Western Pacific and Third Australia-Japan Workshop on Stochastic Models in Engineering, Technology and Management, 426-435.

T. Dohi, H. Okamura, and S. Osaki (1999) Optimal control of preventive maintenance schedule and safety stocks in an unreliable manufacturing environment, Proceedings of International Conference on Industrial Engineering and Production Management, 211-220.

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H. Okamura, T. Dohi, and S. Osaki (1996) Optimal timing strategies for controlled M/G/1 queueing system via diffusion approximation approach, Proceedings of 28th ISCIE International Symposium on Stochastic Systems Theory and Its Applications, 143-148.