不確実性を考慮した最適生産マネジメントシステムに関する研究

要約のみTohoku University伊藤健論

Coping with disassembly yield uncertainty in remanufacturing using sensor embedded products

© 2011, Ilgin et al; licensee Springer.This paper proposes and investigates the use of embedding sensors in products when designing and manufacturing them to improve the efficiency during their end-of-life (EOL) processing. First, separate design of experiments studies based on orthogonal arrays are carried out for conventional products (CPs) and sensor embedded products (SEPs). In order to calculate the response values for each experiment, detailed discrete event simulation models of both cases are developed considering the precedence relationships among the components together with the routing of different appliance types through the disassembly line. Then, pair-wise t-tests are conducted to compare the two cases based on different performance measures. The results showed that sensor embedded products improve revenue and profit while achieving significant reductions in backorder, disassembly, disposal, holding, testing and transportation costs. While the paper addresses the EOL processing of dish washers and dryers, the approach provided could be extended to any other industrial product

Stochastic Inventory Control Systems with Consideration for the Cost Factors Based on EBIT

Semiconductor manufacturing in the current world is more competitive than ever/ is extremely competitive. Due to a short market life-span and high uncertainty in future demand, Supply chain management is a competitive advantage which plays an important role in today`s global semiconductor industry. A very important consequence of uncertain demand and having long lead time is the great risk of incurring shortages and excessive inventory. This paper con-siders the view of the second tier semiconductor supplier in automotive industries and studies, using the periodic review analysis, a single item single stage inventory system with sto-chastic demand. The values of s (reorder point) and Q (order quantity) are the two decisions required to implement the policy. The lead time is assumed known and constant. The only uncertainty is associated with demand. Assuming hold-ing, production, salvage and backorder costs, we determine the optimal numerical value of the level s (reorder point) using a simulation approach, and thus define the optimal inventory policy to minimize the total expected inventory cost while being able to achieve the desired customer service levels

MigSGX: A Migration Mechanism for Containers Including SGX Applications

Recently, containers are widely used to process big data in clouds. To prevent information leakage from containers, applications in containers can protect sensitive information using enclaves provided by Intel SGX. The memory of enclaves is encrypted by a CPU using its internal keys. However, the execution of SGX applications cannot be continued after the container running those applications is migrated. This is because enclave memory cannot be correctly decrypted at the destination host. This paper proposes MigSGX for enabling the continuous execution of SGX applications after container migration. Since the states of enclaves cannot be directly accessed from the outside, MigSGX securely invokes each enclave and makes it dump and load its state. Atthe dump time, each enclave re-encrypts its state using a CPU-independent key to protect sensitive information. For space- and time-efficiency, MigSGX saves and restores a large amount of enclave memory in a pipelined manner. We have implemented MigSGX in the Intel SGX SDK and CRIU and showed that pipelining could improve migration performance by up to 52%. The memory necessary for migration was reduced only to 0.15%.UCC \u2721: 2021 IEEE/ACM 14th International Conference on Utility and Cloud Computing, December 6 - 9, 2021, Leicester, United Kingdo

The Collection and Image Database of Japanese Old Photographs in Bakumatsu-Meiji Period of Nagasaki University Library

Nagasaki University Library began collecting old Japanese photographs, digitizing the images, and entering them into an on-line public database early on. Today, visitors from all over the world can access this site. The collection currently boasts 7,100 photos, making it one of the largest in Japan. This report intends to illustrate how Nagasaki University developed the database and how it is being used

6U CubeSat for Ultraviolet Time-Domain Astronomy

A wide-field ultraviolet observatory for time-domain astronomy utilizing 6U CubeSat is presented. Ultraviolet waveband is one of the unexplored fields in astronomy. Potential targets are short duration transient sources in UV-band: early-phase emission from gravitational wave sources, supernovae shock-breakouts, tidal disruption events around super massive blackholes, etc. The telescope was designed for covering the large error circle of GW detectors, FoV~100 deg2. Thanks to the high quantum efficiency of “delta-doping” detector, the detection limit achieves 20 mag (AB) for 1800 s exposure in NUV band, which is sufficient to detect UV emission from a binary neutron star merger within 200 Mpc from the earth. The satellite has a high-performance on-board computer for on-orbit analysis to detect transient sources and measure the magnitude and the accurate position of the target. The obtained information is required to be transferred to the ground within 30 min from the detection to start multi-messenger follow-up observations utilizing ground-based observatories and astronomical satellites. In this presentation we show the mission overview and conceptual design of the satellite system

Preliminary reports of the Quaternary sediment core drilled in Nakatokushima-cho Tokushima City, West Japan

A 80 m-long borehole core (TK-B-1) drilled in the Tokushima Plain was examined. Based on the sedimentary facies, volcanic ash layers, pollen fossils and radiocarbon dates, this core was divided into the following 13 units. Unit 1 is a metamorphic rock that forms the base of the Tokushima Plain. Units 3 to 8 are Pleistocene and consist of marine and fluvial strata. Units 12-10 are considered to be Alluvium based on radiocarbon dates, and K-Ah tephra found in Unit 11. In Unit 10, we found a volcanic glass concentration derived from AT tephra, but the concentration is a possibility of rework. We intend to reveal the subsurface geological structure of the Tokushima Plain based on the database of borehole data, lithologic stratigraphy, volcanic ash stratigraphy and biostratigraphy