• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.4C
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• pp.353-364
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• 2002

To prevent the performance degradation of TCP due to packet loss in the smooth handoff by the route optimization extension of Mobile If protocol, a buffering of packets at a base station is needed. A buffering of packets at a base station recovers the packets dropped during the handoff by forwarding the buffered packets at the old base station to the mobile user. But, when the mobile user moves to a new foreign network which is connected to a congested router, the buffered packets forwarded by the old base station are dropped and the link utilization performance degraded due to increased congestion by the forwarded packets. In this paper, when the mobile user moves to a new foreign network which is connected to a congested router, Ive propose a packet forwarding control scheme required far the old base station to improve TCP performance in mobile networks. The old base station forwards or discards the buffered packets during handoff by proposed packet forwarding control scheme based on congestion states of RED(Random Early Detection) at the congested router. Simulation results slow that link utilization performance can be improved by applying proposed packet forwarding control scheme.

• Journal of Conservation Science
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• v.28 no.1
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• pp.7-20
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• 2012

This study was to identify the material characteristics and provenance of the Joseon (the 15th to 17th century) potteries from Ssangyongdong Yongam site in Cheonan. The pottery samples of the kilns and the workshops (habitation) from the study area have grey or red color with similar matrix but various shapes and different hardness, according to firing temperature. All of the pottery and the workshop soils were very similar patterns with characteristics of occurrences, mineralogy and geochemical evolution trend. But soils from around the site does not correspond with them. So the workshop soil that the fine clay is raw clay for making pottery in Yongam site. Firing temperature of soft-type potteries were presumed to be formed around $900^{\circ}C$ based on phase transition of clay minerals and mica. Hard-type pottery, mullite was detected and plagioclase was not detected by X-ray diffraction analysis, which means that potteries had experienced firing between 1,000 to $1,100^{\circ}C$.

• Journal of Digital Convergence
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• v.18 no.3
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• pp.317-323
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• 2020

This research is based on product development that improves user experience such as design and function by analyzing the usage behavior of elements experienced by generation Z as customers and users in the process leading to disposal of earphones even before purchase. The behavior of earphones in Generation Z was analyzed through in-depth interview and surveys of the customer experience and user experience of earphones. The results of the study were common or characteristic. They are user experience based on brand dependency, sharing experiences and seeking simplified design and convenience, which is related with the lifestyle of the generation Z. This study is expected to be a fundamental study of product research and marketing strategies that will take advantage of the characteristics of Generation Z, who will be the main player of the market in the future.

• Clean Technology
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• v.9 no.3
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• pp.115-124
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• 2003

Bio industry had rapidly grown up to about 32% annualy mean since '90. To overcome a trade barrier related with environmental issues, which were needed to reduce and reuse pollutants generated from the manufacturing process of product to develop and apply cleaner technology. In this paper, the usefulness of membrane process were surveyed for economical and effective treatment of waste water which were discharged from the production of polymannuronic acid. Concentration efficiencies for U/F 10k, U/F 1k, and N/F were 40%, 60%, and 80% by batch operation. Concentration efficiencies for a combination process of U/F 1k and N/F were 90% by continuous operation. There were a lot of loss of product, which could improve 25% of productivity with recovering product by introducing membrane process.

• Journal of the Korean Geographical Society
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• v.45 no.4
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• pp.461-477
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• 2010

Recent environmental issues such as genetically modified organisms, the loss of biodiversity, climate change, and nuclear waste cannot be reduced to a matter of science or society and explained through nature-society dualist approaches because of their complexity and heterogeneity. This paper examines how nature-society dualism has been embedded in science studies and geography and how this dualism can be overcome. Actor-Network Theory as an attempt to overcome this nature-society dualism is appropriate in analysing "strange imbriglio" of biology, politics, technoscience, market, value, ethics and facts that constitute our society by focusing on heterogeneous association, and can contribute to providing a useful framework to solve environmental problems.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.6C
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• pp.581-593
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• 2002

In this paper, we proposed an Adaptive RIO scheme to solve the problem of RIO scheme that occurs when admission control is performed for QoS guarantee of Assured Service in Differentiated Services. To prevent an early random drop of the admitted In-profile packet, proposed Adaptive RIO scheme updates parameters of RIO scheme every time interval according to the estimated numbers of maximum packet arrivals of In-profile traffic and total traffic during the next time interval. The numbers of maximum packet arrivals during the next time interval are estimated based on the buffer size determined by the network topology and the ratio of bandwidth allocated to each subclass. We found from simulation results that, compared with RIO scheme, proposed Adaptive RIO scheme can improve performance of the throughput for In-profile traffic when admission control is performed or congestion occurs.

• The KIPS Transactions:PartC
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• v.9C no.2
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• pp.277-282
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• 2002

In general, requirements for QoS are different according to the type of services in wire-line and wireless ATM networks, and real-time video service is more sensitive to cell transmission delay than to cell loss. Existing handoff schemes emphasizing prevention of cell loss had limitations in cell transmission delay to satisfy QoS. In this paper, a novel scheme to transmit ATM cells with low CLP(when CLP = 0) prior to others and discarding cells with high CLP(when CLF = 1) in ATM cell header among cells to be forwarded to new base station during handoffs in real-time VBR service is proposed. The proposed scheme is proven to be suitable for the satisfaction of QoS of real-time VBR service and appropriate for fast handoffs by giving high CLP value to less meaningful MPEG frames through simulations.

• Journal of Chest Surgery
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• v.34 no.12
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• pp.956-959
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• 2001

The Iymphoproliferative disease after the organ transplantation is more commonly seen with the increase according to the increasing number of the organ transplantations and it occurs more frequently in the cases of heart and lung transplantations that needs more aggressive immunosuppression. It demands urgent evaluation and management because of poor prognosis. We transplanted left lung of a man to the woman who suffered from severe dyspnea due to terminal pulmonary emphysema in discrepancy of ABO blood type. Postoperatively, We used triple regimen immunotherapy(cyclosporin, azathioprine, prednisolone) and followed up in the out patient clinic. During the follow up, we found abnormal mass lesion on the transplanted lung and performed gun biopsy. We confirmed malignant lymphoma on the pathollgic examination and two cycled chemotherapy was given after reducing dose of immunosupression. The patient died of sudden onset of pulmonary edema of the transplanted lung.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.5
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• pp.1117-1132
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• 2019

Recently, IT technology such as internet, mobile, and IOT has rapidly developed, making it easy to collect data necessary for business, and the collected data is analyzed as a new method of big data analysis and used appropriately for business. In this way, data collection and analysis becomes easy. In such data, personal information including an identifier such as a sensor id, a device number, IP address, or the like may be collected. However, if systematic management is not accompanied by collecting and disposing of large-scale data, violation of relevant laws such as "Personal Data Protection Act". Furthermore, data quality problems can also occur and make incorrect decisions. In this paper, we propose a new data governance maturity model(DGMM) that can identify the personal data contained in the data collected by companies, use it appropriately for the business, protect it, and secure quality. And we also propose a over all implementation process for DG Program.

• Journal of Korean Society of Archives and Records Management
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• v.7 no.2
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• pp.43-71
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• 2007

The Records and Archival Management System of Korean Government was founded in the early 1960s after the overall national structure reform and the implementation of the new administrative management technique, which boosted the efficiency of the way of conducting business, into the public administration, and Promoted in 1962, the records appraisal and destruction works included not only retention and destruction of official documents but also the development of efficient management and elimination systems for official documents to be produced in the future. and Korean government elaborated the appraisal system to stipulate the retention period on the basis of functional classification and documentary function.