• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.11 no.4
• /
• pp.760-765
• /
• 2007

In this paper, the threshold voltage roll-off and drain induced barrier lowering(DIBL) have been analyzed for nano structure double gate FinFET. The analytical current model has been developed, including thermionic current and tunneling current models. The potential distribution by Poisson equation and carrier distribution by Maxwell-Boltzman statistics were used to calculate thermionic omission current, and WKB(Wentzel- Kramers-Brillouin) approximation to tunneling current. The threshold voltage roll-offs are obtained by simple adding two currents since two current is independent. The threshold voltage roll-off by this model are compared with those by two dimensional simulation and two values are good agreement. Since the tunneling current increases especially under channel length of 10nm, the threshold voltage roll-off and DIBL are very large. The channel and gate oxide thickness have to be fabricated as thin as possible to decrease this short channel effects, and this process has to be developed.

• Electronics and Telecommunications Trends
• /
• v.37 no.3
• /
• pp.74-84
• /
• 2022

The Korean mobile service market has persistently grown with the number of subscribers and volume of mobile traffic. It shows the slow diffusion of 5G subscribers, and rapid growth of both the MVNO(Mobile Virtual Network Operator) market and unlocked mobile phones. Therefore, this study derives the direction of telcos' strategies and policy implications by empirically analyzing the usage and attitude of LTE and 5G subscribers. Our major findings are as follows: First, our current mobile service subscription market constitutes most long-term customers for their incumbent carriers only by device change from lock-in with bundle services. Mobile tariffs, data speed, and benefits of bundle services are important factors affecting choices and customers' satisfaction with a provider and intentions of churning to another. Second, demand and satisfaction for using 5G are less because speeds and service tariffs act as pain points for 5G services. Third, the users' high preferences for MVNOs and unlocked mobile phones are linked to their subscription to MVNOs' low-cost plans with unlocked mobile phones on online channels. These streams lead to a big change in the market competition that MNO(Mobile Network Operator)s' market shares are expected to decrease and MVNOs' shares will be increased by two times, in the near future. Therefore, MNOs need to change their distribution strategies from offline to online channels and try to resolve the stereotype, "mobile tariffs are expensive," by enhancing their service values. Finally, as consumers prefer one-stop service in the same channel regardless of the distribution channel, policies should focus on the consumers' needs for convenience rather than on the channel separation for perfectly unlocked mobile phones.

• Geomechanics and Engineering
• /
• v.28 no.6
• /
• pp.613-624
• /
• 2022

A study of the evolution of overburden fractures under the solid-fluid coupling state was conducted based on the geological and mining characteristics of the coal seam depth, weak strata cementation, and high-intensity mining in the mining areas of West China. These mining characteristics are key to achieving water conservation during mining or establishing groundwater reservoirs in coal mines. Based on the engineering background of the Daliuta Coal Mine, a non-hydrophilic simulation material suitable for simulating the weakly cemented rock masses in this area was developed, and a physical simulation test was carried out using a water-sand gushing test system. The study explored the spatial distribution and dynamic evolution of the fractured zone in the mining overburden under the coupling of stress and seepage. The experimental results show that the mining overburden can be vertically divided into the overall migration zone, the fracture extension zone and the collapse zone; additionally, in the horizontal direction, the mining overburden can be divided into the primary fracture zone, periodic fracture zone, and stop-fracture zone. The scope of groundwater flow in the overburden gradually expands with the mining of coal seams. When a stable water inrush channel is formed, other areas no longer generate new channels, and the unstable water inrush channels gradually close. Finally, the primary fracture area becomes the main water inrush channel for coal mines. The numerical simulation results indicate that the overlying rock breaking above the middle of the mined-out area allows the formation of the water-conducting channel. The water body will flow into the fracture extension zone with the shortest path, resulting in the occurrence of water bursting accidents in the mining face. The experimental research results provide a theoretical basis for the implementation of water conservation mining or the establishment of groundwater reservoirs in western mining areas, and this theoretical basis has considerable application and promotion value.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.1B
• /
• pp.73-81
• /
• 2009

This paper presents a numerical investigation of the impact of the secondary currents on solute transport in open-channel flows. The RANS model with Reynolds stress model is used for flow modeling, and the GGDH(generalized gradient diffusion hypothesis) model is used to close the scalar transport equation. Using the developed model, the impact of secondary currents on solute transport in open channel flows over smooth-rough strip is investigated. Through numerical experiments, the secondary currents are found to affect the solute spreading, leading a movement of the position of the peak concentration and a skewed distribution of solute concentration. Due to the lateral flow of secondary currents near the free surface, the concentration at the rough strip is found to be larger than that at the smooth strip bed. The solute at the rough strip is more rapidly transported than smooth bed. A magnitude analysis of the solute transport rate in scalar transport equation is also carried out to investigate the effect of secondary currents and scalar flux on the concentration distribution.

• Journal of Distribution Science
• /
• v.20 no.7
• /
• pp.107-117
• /
• 2022

Purpose: The scope of forensic investigations serves to identify malicious activities, including leakage of crucial corporate information. The investigations also identify security lapses in available networks. The purpose of the present study is to explore how to block distribution channels to protect illegal leakage in supply chain through digital forensic method. Research design, data and methodology: The present study conducted the qualitative textual analysis and its data collection process entails five steps: identifying and collecting data, determining coding categories, coding the content, checking validity and reliability, and analyzing and presenting the results. This methodology is a significant research method due to its high quality of previous resources. Results: Applying previous literature analysis to the results of this study, the author figured out that there are four solutions as an evidences to block distribution channels, preventing illegal leakage regarding company information. The following subtitles show clear solutions: (1) Communicate with Stakeholders, (2) Preventing and addressing illegal leakage, (3) Victims of Data Breach, (4) Focusing Solely on Technical Teams. Conclusion: There are difficult scenarios that continue to introduce difficult questions surrounding engagement with digital evidence. Consequently, it is important to enhance data handling to provide answers for organizations that suffer due to illegal leakages of sensitive information.

• Nuclear Engineering and Technology
• /
• v.53 no.5
• /
• pp.1429-1435
• /
• 2021

The temperature distribution of an electromagnetic pump was analyzed with a flow rate of 1380 L/min and a pressure of 4 bar designed for the sodium thermo-hydraulic test in the Sodium Test Loop for Safety Simulation and Assessment-Phase 1 (STELLA-1). The electromagnetic pump was used for the circulation of the liquid sodium coolant in the Intermediate Heat Transport System (IHTS) of the Prototype Gen-IV Sodium-cooled Fast Reactor (PGSFR) with an electric power of 150 MWe. The temperature distribution of the components of the electromagnetic pump was numerically analyzed to prevent functional degradation in the high temperature environment during pump operation. The heat transfer was numerically calculated using ANSYS Fluent for prediction of the temperature distribution in the excited coils, the electromagnet core, and the liquid sodium flow channel of the electromagnetic pump. The temperature distribution of operating electromagnetic pump was compared with cooling of natural and forced air circulation. The temperature in the coil, the core and the flow gap in the two conditions, natural circulation and forced circulation, were compared. The electromagnetic pump with cooling of forced circulation had better efficiency than natural circulation even considering consumption of the input power for the air blower. Accordingly, this study judged that forced cooling is good for both maintenance and efficiency of the electromagnetic pump.

• Journal of Distribution Science
• /
• v.22 no.8
• /
• pp.87-98
• /
• 2024

Purpose: This study aimed to examine the influence of private label cues, including store image, product design, price promotion, and origin image, on consumers repurchase intention by mediating consumption value from a distribution perspective. Additionally, it explored nationality's moderating role in the relationship between consumption value and repurchase intention. Research design, data and methodology: Drawing on the SOR model, data were collected from 246 consumers who had purchased private-label products in the past month. Structural equation modeling analysis was employed to test hypotheses using AMOS and SPSS. Results: Findings revealed that cues significantly impact consumers' perception of consumption value, influencing repurchase intention. Price promotion directly affected repurchase intention, while other cues indirectly influenced it through consumption value mediation. Nationality moderated the relationship between consumption value and repurchase intention, with Korean consumers showing a higher propensity to repurchase than Chinese consumers. Conclusions: Theoretical implications of the study contributed to understanding consumer behavior by confirming the impact of private label cues, elucidating their differential effects on repurchase intention, and integrating theoretical frameworks. Managerial implications underscored the significance of leveraging cues to enhance consumption value perceptions, tailoring marketing strategies to accommodate cultural nuances, and utilizing cues to bolster consumer repurchase intentions, ultimately enhancing distribution channel effectiveness.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.40 no.6
• /
• pp.1045-1061
• /
• 2016

This study clarifies differences in attitudes toward the Omni-Channel service (Pintech service, Beacon service, and Click and Collect service) and fashion consumption behavior among four clusters grouped by level of technology readiness. An online survey was conducted; 572 individuals between 20 and 30 years of age were collected, but only 539 were used. Factor analysis, cluster analysis, descriptive statistics, ANOVA, and frequency analysis were adopted to analyze data using SPSS 20.0. The results are as follows. Technology readiness was divided into four factors: optimism, innovativeness, discomfort, and insecurity. Participants were divided into four groups according to four sub-factors of technology readiness: brave adopters, optimistic laggards, indifferent adopters, and critical adopters. These groups showed significant differences in attitudes toward the Omni-Channel service and fashion consumption behavior. Critical adopters and brave adopters recognized the value of the Omni-Channel service and had more positive attitudes toward it than other groups. Critical adopters also better perceived the risk of service with new technology that showed higher fashion innovativeness and monthly consumption of fashion products than other groups. We inferred that the indifferent adopters did not use the Omni-Channel service or services offered by fashion retailers as much as other groups because indifferent adopters were less interested in both the Omni-Channel service and fashion consumption behavior than other groups. Optimistic laggards viewed the Omni-Channel service optimistically, despite perceptions of high risks to accompanying it and a low intent to use it. The results of this study assisted in the formation of a theoretical framework of consumer behavior associated with the Omni-Channel, which is an emerging issue in research related to distribution. The results can help fashion industries that operate consumer-oriented marketing based on Omni-Channel strategies.

• Journal of KIISE:Databases
• /
• v.35 no.6
• /
• pp.518-532
• /
• 2008

Broadcast scheme has been widely researched for efficient data delivery in the mobile environment because the downlink capacity of a mobile client is much greater than the uplink capacity, and the power of a mobile client is limited. In the proposed scheme, the index lets the client know when data items would be broadcasted and enables the client to minimize the tuning time and power consumption. Single channel index schemes are fit to flat broadcast that performs well when all the broadcasted data items are accessed with the same probability whereas the multi-disk broadcast scheme is proper when the data access distribution is skewed. The existing index schemes, however, cannot work on the Multi-disk broadcast scheme because they cannot point the replicating data items in a broadcast cycle. This paper proposes a Multi-disk Exponential Index (MDEI) which is a single channel index scheme fit to Multi-disk broadcast scheme. Because MDEI scheme organizes a separate index for each disk, it functions with multi-disk broadcast, resulting in a greater reduction of average access latency than that of other flat-broadcast index schemes when the data access distribution is skewed. The performance evaluation showed that MDEI has a good performance when data access distribution is skewed. MDEI has short average access latency and not much average tuning time when the data access distribution is skewed.

• The Korean Journal of Quaternary Research
• /
• v.3 no.1
• /
• pp.17-34
• /
• 1989

The distribution characteristics of incised meander river are analysed concerning topography, geology, stream order and altitude. Additionally geomorphological development of the Korean peninsular is considered with incised meander. The main findings are as follows: 1. The incised meander is intensively distributed on the west and north slope of T'aebak and Sobaek mountain range, but sparsely distributed on the opposite slopes. 2. Geologically, the occurrence rate of incised meander is high orderly as follows: Joseon supergroup, Pyeongan supergroup, Daedong supergroup metamorphic rock, Gyeongsang supergroup, and granite. The incised meander is developed well on the following conditions: hard rocks against weathering, stratified structure, geologic arrange across the river channel and contacting zone of geological formations. 3. The higher stream orders are, the higher occurrence of incised meander is. 4. Comparing the altitude of present river bed with the summit level of restored map, it is supposed that the incised meander rivers have been dissected about 300-500m down ward. 5. Considering the distribution characteristic of incised meander, it is suggested that not only T'aebak mountain range but Sobaek mountain range is the axis of asymmetrical up-warping in the Korean peninsular. 6. Considering the distribution characteristic of incised meander on the restored map and the stream order, it seems that present incised meander channel was inherited from antecedent meander river that had flowed on High and Middle level erosion surface. But the channel pattern has been modified.