• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.4
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• pp.253-262
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• 2004

Construction of tunnels in a deep crystalline host rock for a potential High-Level Radioactive Waste(HLW) repository inevitably generates an excavation disturbed zone (EDZ). There have been a series of debates on whether a permeability in an EDZ increases or not and what would be the maximum depth of an EDZ. Recent studies show mixed opinions on permeability. However, there has been an international consensus on the thickness of an EDZ; 30 cm for TBM and 1 meter for controlled blast. One of the impacts of an EDZ is on determining the distance between adjacent deposition holes. The void gap by the excavation hinders relaxation of temperature profiles so that the current Korean reference designing distance between holes should be stretched out more to keep the maximum temperature in a buffer region below 100 degrees Celsius. The other impact of an EDZ is on the long-term post closure radiological safety. To estimate the impact, the reference scenario, the well scenario, is chosen. Released nuclides diffuse through a bentonite buffer region experiencing strong sorption and reach a fracture surrounded by a porous medium. Inside a fractured porous region, radionuclides migrate by advection and dispersion with matrix diffusion into a porous medium. Finally, they reach a well assumed to be a source of potable water for local residents. The annual individual dose is assessed on this well scenario to find out the significance of an EDZ. A profound sensitivity study was performed, but all results show that the impact is negligible. Even though the role of an EDZ turns out to be limited on overall safety assessment, still it is worthwhile to study the chemical role of an EDZ, such as a potential source for natural colloids, potential sealing of an open fracture by fine clay particles generated by the process of an EDZ, and alteration of a sorption mechanism by an EDZ in the future.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.5
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• pp.79-89
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• 1984

In this paper we present development of microprocessor-based 8-channel statistical multiplexer (SMUX). The hardware design includes one Z-80A CPU board with the clock rate of 4 MHz, one 16 Kbyte ROM board for program storage, one 16 Kbyte dynamic RAM board and three I/O boards, all connected through an S-100 compatible tristate bus. The SMUX can presently multiplex 8 channels with data rates ranging 50 bps to 9600 bps, but can be reduced to accommodate 4 channels by having a slight modification of software and removing one terminal I/O board. The system specifications meet CCITT recommendations X.25 link level, V.24, V.28, X.3 and X.28. Significant features of the SMUX are its capability of handling 4 input codes (ASCII, EBCDIC, Baudot, Transcode), the use of a dynamic buffer management algorithm, a diagnostic facility, and the efficient use of a single CPU for all system operation. Throughout the paper, detailed explanations are given as to how the hardware and software of the SMUX system have been designed efficiently.

• Journal of Korean Society of Transportation
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• v.28 no.5
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• pp.77-87
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• 2010

In the last five years, Korea has supplied many more bicycle facilities than in the last several decades combined. However, have bicyclists increased in proportion to investment? If bicyclists are avoiding existing bicycle related facilities, including off-road bicycle facilities, it could be because suppliers did not consider bicyclists' preferences in their planning process. In this paper, the authors tried to understand the bicyclists' behavioral and route choice characteristics using stated preference surveys and a logit model, using commuting time in Daejeon Metropolitan City, Korea. The results show that nine factors affect the route choice behavior of bicyclists. In particular, bicyclists preferred sub-arterial roads to off-road, dedicated bicycle facilities in residential area. It means that bicyclists like a seamless bicycle route and that a buffer zone between car lanes and bicycle lanes or 50 km/h speed limits for cars are necessary for bicycle lanes that are not physical separated.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.1
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• pp.38-44
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• 1993

A model for BICMOS buffer switching operation is presented, including the influence of bipolar base transit time and collector-base capacitances. A closed-form solution for the propagation delay-time is obtained assuming low level injection and channel velocity limitation. For the high level injection case, the delay-times are numerically obtained using effective current gain. These results are compared with those by HSPICE simulation, which shows good agreement. It is noted that the collector-base capacitance strongly affects the delay-time. The effects of voltage scaling are also investigated, which shows the model can be applied for the reduced supply voltages.

• Korean Management Science Review
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• v.28 no.3
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• pp.15-29
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• 2011

In this paper, we consider a system working at both primary service and secondary service. A server can switch between the primary service and the secondary service or it can be assigned to secondary service as a dedicated server. A service policy is characterized by the number of servers dedicated to the secondary service and a rule for switching the remaining servers between two services. The primary service system is modelled as a Markovian queueing system and the throughput is a function of the number of servers, buffer capacity, and service policy. And the secondary service system has a service level requirement strategically determined to perform the service assigned. There is a revenue obtained from throughput and costs due to servers and buffers. We study the problem of simultaneously determining the optimal total number of servers, buffers, and service policy to maximize profit of the system subject to both an expected customer waiting time constraint of the primary service and a service level constraint of the secondary service and develop an algorithm which can be successfully applied with the small number of computations.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.6
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• pp.725-732
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• 2014

The silencer for the medium caliber gun was studied to reduce the propagation of gun-generated noise from the firing test range to the community. Three types of silencer were made to compare the reduction of sound pressure level and the effect of chamber volume and the exit angle to the reduction of sound pressure was considered. The structural analysis and measurement of pressure in the silencer showed that the structure is safe in terms of strength. The increase of recoil force to buffer must be considered in the development of silencer. The hypothesis test on the muzzle velocity for the existence of silencer showed that there are no difference at the significance level of 0.05.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.130.3-131
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• 2003

The biological effects of NADPH-dependent isocitrate dehydrogenase (IDPc) inhibitor. DA-11004, was examined in obese zucker rats or streptozotocin-induced diabetic SD rats. Diabetes was induced by injection of streptozotocin (50mg/kg) dissolved in citrate buffer (pH 4.8) into the tail vein and induction of diabetes was confirmed by the measurement of the tail blood glucose level at 48h. DA-11004 (30mg/kg, po) was injected for successive 7days and significantly reduced the plasma glucose in streptozotocin-induced diabetic rats (P<0.05). (omitted)

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.9B
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• pp.596-601
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• 2005

In this paper it is focused on the relation between CLR(Cell Loss Ratio) and blocking probability in the wireless ATM access transport. Traffic model of wireless ATH access transport is based on the cell scale, burst scale and call connection level. The CLR due to buffer overflow for wireless access node is derived for VBR traffic. The CLR due to transmission errors for wireless channel is derived. Using the CLR for both access node and wireless channel: the CLR of wireless ATM access transport is derived. The relation between CLR and blocking probability is analyzed for VBR traffic to evaluate performance of wireless ATM access transport.

• Journal of Families and Better Life
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• v.23 no.6 s.78
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• pp.145-153
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• 2005

The purpose of this study was to analyze the impacts of consumers' demographic characteristics on their involvement in retired communities, under the assumption that consumers' involvement in retired communities would be a preceding factor of the consumers' preferences for retired communities. One of the major findings of this study was that there were statistically significant differences in the involvement in retired communities by several demographic variables such as age, gender, level of education, income, total family asset, consumer values, and pursuit of happiness. Second, such involvement was strongly correlated with consumer preferences. Third, the community management styles, such as sales and rental conditions, significantly influenced consumers' level of preference. The results from this study could provide useful information not only for understanding the residents of retired communities, buffer enhancing the welfare of residents of retired communities.

• Journal of the Korea Society for Simulation
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• v.14 no.1
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• pp.33-42
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• 2005

Service Level Agreement (SLA) is a service providing scheme by a service class agreement between a user and a service provider SLA allows that a user can select an expected service class in various service classes provided from a service provider. Recently, SLA management is adapted to support the end-to-end Qos for service users in Beyond 3 Generation (B3G) networks. In B3G networks, SLA provides multiple service classes on access networks so that service classes should be managed to assure the service satisfaction for users. In this paper, we propose a dynamic Qos management scheme by IP traffic class controlling based on SLA in B3G networks. Also, to manage dynamic traffic service, we consider Differentiated services (Diffserv) mechanism for the resource management by SLA. An If service traffic class on SLA can be dynamically changed by Diffserv traffic management to support dynamic end-to-end Qos. Hence, in this paper, we consider the buffer threshold scheme for controlling traffic loads and the traffic level control scheme for implementing the dynamic traffic management by the SLA.