• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.9
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• pp.2373-2384
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• 1996

Connection caching technique is widely used to reduce the overhead incurred by frequency connection establishment in distributed computing environment using connection oriented protocol. We present an efficient connection caching scheme where we divide the system into several host groups and connection between the hosts in the same group is kept prior to others. In other words it makes the connection kept longer by sharing the connection use information between hosts in the same group. Every host group consists of hosts which have heavy intercommunication. And we present performance evaluation of the effect of host grouping upon connection caching and performance comparison of various grouping in several aspects includingmeanservice request interarrival time, mean service time, group size, grouping and type of group. Simulation results show that host grouping is effective in evrey performance criterion and proper grouping of hosts enhances the performance. We also present analysis results for Markov process model of our scheme which are consistent with the simulation results.

• International journal of advanced smart convergence
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• v.10 no.1
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• pp.142-150
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• 2021

Open-channel SSD is a new type of Solid-State Disk (SSD) that improves the garbage collection overhead and write amplification due to physical constraints of NAND flash memory by exposing the internal structure of the SSD to the host. However, the host-level Flash Translation Layer (FTL) provided for open-channel SSDs in the current Linux kernel consumes host memory excessively because it use page-level mapping table to translate logical address to physical address. Therefore, in this paper, we implemente a selective mapping table loading scheme that loads only a currently required part of the mapping table to the mapping table cache from SSD instead of entire mapping table. In addition, to increase the hit ratio of the mapping table cache, filesystem information and mapping table access history are utilized for cache replacement policy. The proposed scheme is implemented in the host-level FTL of the Linux kernel and evaluated using open-channel SSD emulator. According to the evaluation results, we can achieve 80% of I/O performance using the only 32% of memory usage compared to the previous host-level FTL.

• Korean Journal of Pharmacognosy
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• v.36 no.2 s.141
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• pp.93-96
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• 2005

Mutagenicity of Gamgung-tang (GGT) was tested using in vitro S-9 mixture in vitro host-mediated assay with Salmonella typhimurium. In the previous reports, GGT was tested for the safety using Ames(-S-9), Bacillus subtilis Rec, and umu gene expression mutagenicity tests. Mutagenic activity in any assays we tested was not found. In this report, we further investigated safety of GGT after metabolic activation in vivo. Ames test with S-9 mixture and host-mediated assay with Salmonella typhimurium TA98 were used to identify metagenic property of GGT. GGT was administered 3 times with i.m. to Balb/c mice did not induced mutagenic effect in Salmonella typhimurium TA98 recovered from the liver after 3.5h with i.p. treatment. Over the entire dose range $(3{\sim}150mg/mouse)$ tested no toxicity was detected to the bacterial cells. These results suggest that there was no DNA damage and mutagenicity by GGT.

• The Journal of Society for e-Business Studies
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• v.24 no.2
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• pp.55-70
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• 2019

It is essential to consider the relationships between each component in the communication infrastructure in order to build and optimize the infrastructure. In this paper, based on the major factors to consider for the optimized communication infrastructure, we propose an enhanced MACSec-based deployment mechanism for communication infrastructure. The proposed MACSec mechanism can replace the IPSec without the additional devices and redesign of the communication infrastructure. In addition, we evaluate the performance of MACSec and IPSec in terms of the major factors such as message overhead, encryption processing, and host mobility. According to the evaluation results, we can say that MACSec is superior to IPSec with regard to mobility as well as hop delay and message overhead.

• The Journal of the Korean dental association
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• v.22 no.1 s.176
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• pp.37-48
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• 1984

Clinical assessment of bone-graft healing in the maxillofacial region is generally limited to clinical evaluation, radiographs, and biopsy. Sequential interpretation of osseous repair, more sensitive than with conventional radiography is possible with a non-invasive, non-destructive radionuclide method. Technetium-99m radionuclide bone scan was used in the evaluation of the progress of osteogenic activity in autologous iliac bone graft and freeze-dried bone allograft of dog's mandible. Bone scan was performed at 1wk, 2wk, 4wk, 6wk, and 8wk after grafting. In autologous graft the activity ratio for the graft bone remained greater than that of the host since 2자 after grafting; however, in lyophilized allograft the activity ratio for graft bone was greater than that of the host at 6자 after grafting.

• Korean Journal of Weed Science
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• v.31 no.1
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• pp.103-111
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• 2011

Monochoria vaginalis var. plantaginea (Pontederiaceae) is one of the most problematic weed in the rice field in Korea. Tanysphyrus (Tanysphyroides) major was selected as a potential biological control agent for M. vaginalis. Continuous rearing of T. (T.) major was carried out from 2006 to 2007, and its morphological characteristics and ecological characteristics were investigated. This species has a single generation per year, over-wintering as an adult stage. The emergence of adults starts in later June and last until September. These observations indicate that T. (T.) major takes $22{\pm}0.7$ days to develop from egg to adulthood. Host specificity test showed that finally selected this species was suitable candidates for the biological control of M. vaginalis var. plantaginea since it showed negative host specificity against major 60 test crops.

• KIPS Transactions on Computer and Communication Systems
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• v.8 no.7
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• pp.159-166
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• 2019

Unlike modern Solid-State Drives with DRAM, DRAM-less SSDs do not have DRAM because they are cheap and consume less power. Obviously, they have performance degradation problem due to lack of DRAM in the controller and this problem can be alleviated by utilizing host memory buffer(HMB) feature of NVMe, which allows SSDs to utilize the DRAM of host. In this paper, we show that commercial DRAM-less SSDs surely exhibit lower I/O performance than other SSDs with DRAM, but they can be improved by utilizing the HMB feature. Through various experiments and analysis, we also show that DRAM-less SSDs mainly exploit the DRAM of host as mapping table cache rather than read cache or write buffer to improve I/O performance.

• Journal of Internet of Things and Convergence
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• v.2 no.2
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• pp.37-49
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• 2016

An IP address is used as a host identifier and a locator to bind hosts and applications to their location in existing Internet. Several protocols are proposed to eliminate this binding. Most of these protocols use IPv6-based host identifiers to maintain compatibility with existing Internet, but these identifiers cannot be handled by standard IPv6 routers because such identifiers are unroutable. Therefore, host identifiers need to be usually converted to locators at hosts, and the standard IPv6 protocol should be modified to interoperate with these protocols. In this paper, we propose a network-based host identifier locator separating scheme in software-defined networking. The proposed scheme separates the underlying network into Host Identity and IP domains in order to directly forward unroutable identifiers. The Host Identity domain operates as an overlaid network over IP domain, and it makes the unroutable identifiers to be routable using distributed hash table based routing strategy. For the evaluation, we compared the proposed scheme with the previous scheme using signaling costs and packet delivery costs. The result shows that the proposed scheme is more suitable in the recent mobile-based environments.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3870-3884
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• 2020

The proposed framework of Four Layer Robust Storage in Cloud (FLRSC) architecture involves host server, local host and edge devices in addition to Virtual Machine Monitoring (VMM). The goal is to protect the privacy of stored data at edge devices. The computational intelligence (CI) part of our algorithm distributes blocks of data to three different layers by partially encoded and forwarded for decoding to the next layer using hash and greed Solomon algorithms. VMM monitoring uses snapshot algorithm to detect intrusion. The proposed system is compared with Tiang Wang method to validate efficiency of data transfer with security. Hence, security is proven against the indexed efficiency. It is an important study to integrate communication between local host software and nearer edge devices through different channels by verifying snapshot using lamport mechanism to ensure integrity and security at software level thereby reducing the latency. It also provides thorough knowledge and understanding about data communication at software level with VMM. The performance evaluation and feasibility study of security in FLRSC against three-layered approach is proven over 2³² blocks of data with 98% accuracy. Practical implications and contributions to the growing knowledge base are highlighted along with directions for further research.

• Journal of Korea Multimedia Society
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• v.3 no.3
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• pp.280-289
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• 2000

This paper presents an efficient method to provide seamless communication in mobile wireless networks. The goal of seamless communication is to provide disruption free service to a mobile user. A disruption in service could occur due to active handoffs. There are many user applications that do not require a total guarantee for disruption free service but would also not tolerate very frequent disruptions. This paper proposes an extended staggered multicast that provides a probabilistic guarantee for disruption free service. The proposed multicast forecasts the direction and velocity for a mobile host. It is possible that data packets for a mobile host are multicasted to not all neighbor cells but a par\ulcorner of neighbor cells those the mobile host will be handoff potentially on the basis of these information. Therefore, the extended staggered multicast significantly reduces the static network bandwidth usage also provides a probabilistic guarantee for disruption free service.