• Proceedings of the KIEE Conference
• /
• 2005.07e
• /
• pp.49-51
• /
• 2005

This paper presents the potential interferences in various grounding electrode systems. The ground potential rise and potential interference coefficients were calculated as a function of the configuration and size of grounding electrodes and the distance between grounding electrodes. The potential rise and potential interference coefficient strongly depend on the distance between grounding electrodes, the shape and size of grounding electrodes.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.20 no.4
• /
• pp.29-36
• /
• 2006

This paper deals with the potential interferences between grounding electrodes in various grounding electrodes. The ground potential rise and potential interference coefficients were measured by using and electrolytic tank and calculated by CDEGS program as functions of the configuration and size of grounding electrodes and the distance between grounding electrodes. The ground potential rise and potential interference coefficient strongly depend on the distance between grounding electrodes, the shape and size of grounding electrodes. The potential rise interferences between grounding grid and grounding grid is lower than those between grounding grid and ground rod.

• Journal of the Korea Society of Computer and Information
• /
• v.24 no.3
• /
• pp.1-9
• /
• 2019

This paper presents three potential risks in an environment that simultaneously performs the garbage collection and wear leveling in NAND flash memory. These risks may not only disturb the lifespan improvement of NAND flash memory, but also impose an additional overhead of page migrations. In this paper, we analyze the interference of garbage collection and wear leveling and we also provide two theoretical considerations for lifespan prolongation of NAND flash memory. To prove two solutions of three risks, we construct a simulation, based on DiskSim 4.0 and confirm realistic impacts of three risks in NAND flash memory. In experimental results, we found negative impacts of three risks and confirmed the necessity for a coordinator module between garbage collection and wear leveling for reducing the overhead and prolonging the lifespan of NAND flash memory.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.11
• /
• pp.5304-5322
• /
• 2018

Since designing a feedback topology is a practical way to implement interference alignment at reduced cost of channel state information (CSI) feedback, six feedback topologies have been presented in prior works for a K-user multiple-input multiple-output interference channel. To fully reveal the potential benefits of the feedback topology in terms of the saving of CSI overhead, we propose a new feedback topology in this paper. By efficiently performing dimensionality-decreasing at the transmitter side and aligning interference signals at a subset of receivers, we show that the proposed feedback topology obtains substantial reduction of feedback cost over the existing six feedback designs under the same antenna configuration.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.20 no.3
• /
• pp.28-35
• /
• 2006

Recently, a number of equipments related with electricity, electronics, and communication in the same building are needed to the grounding system for safety from unexpected accidents. When the faulted electric current flows into a certain grounding system, the potential rise in that system takes place and it might induce the potential rise to other grounding system. This potential interference was strongly affected by the surface potential, which was deeply related with the electrode shape. In this paper, the fundamental formula was deduced on the basis of surface potential of two grounding electrodes. Which corresponds to source of the potential interference and other grounding electrode, respectively. Therefore, the degree of potential interference in this mesh grounding electrode system was verified by the simple model simulation. In addition, in order to identify the difference between the grounding resistance in the realistic construction site and the expected value from the corresponding simulation, the experiment was performed with model on a reduced scale about the realistic grounding system. It consists of stainless steel hemisphere electrodes in a water tank. From this work, the grounding resistance in the mesh grounding electrode showed the good coincidence results between those. Consequently, it is confirmed that the grounding resistance in the mesh electrode is possible to be estimated by performing the experiment using the water tank model.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.13 no.2
• /
• pp.494-513
• /
• 2019

A multi-channel access problem based on hypergraph model in ultra-dense small cell networks is studied in this paper. Due to the hyper-dense deployment of samll cells and the low-powered equipment, cumulative interference becomes an important problem besides the direct interference. The traditional binary interference model cannot capture the complicated interference relationship. In order to overcome this shortcoming, we use the hypergraph model to describe the cumulative interference relation among small cells. We formulate the multi-channel access problem based on hypergraph as two local altruistic games. The first game aims at minimizing the protocol MAC layer interference, which requires less information exchange and can converge faster. The second game aims at minimizing the physical layer interference. It needs more information interaction and converges slower, obtaining better performance. The two modeled games are both proved to be exact potential games, which admit at least one pure Nash Equilibrium (NE). To provide information exchange and reduce convergecne time, a cloud-based centralized-distributed algorithm is designed. Simulation results show that the proposed hypergraph models are both superior to the existing binary models and show the pros and cons of the two methods in different aspects.

• 한국정보통신설비학회:학술대회논문집
• /
• 2009.08a
• /
• pp.104-107
• /
• 2009

In this paper, we analyze the effect of interference between DTV system and IEEE 802.11n. We set DTV as a victim receiver and IEEE 802.11n as an interfering system. When they exist in the same area, they can make an interference effect. Therefore, we calculate a minimum coupling loss (MCL) and compare the resulting value with a path loss for determining whether there exists a potential interference or not. The minimum separation distance is determined when the path loss is larger than the MCL.

• ETRI Journal
• /
• v.39 no.2
• /
• pp.255-263
• /
• 2017

This paper proposes a graph-theatrical approach to optimize spatial reuse by adopting a technique that quantizes the channel information into single bit sub-messages. First, we introduce an interference graph to model the network topology. Based on the interference graph, the computational requirements of the algorithm that computes the optimal spatial reuse factor of each user are reduced to quasilinear time complexity, ideal for practical implementation. We perform a resource allocation procedure that can maximize the efficiency of spatial reuse. The proposed spatial reuse scheme provides advantages in beamforming systems, where in the interference with neighbor nodes can be mitigated by using directional beams. Based on results of system level measurements performed to illustrate the physical interference from practical millimeter wave wireless links, we conclude that the potential of the proposed algorithm is both feasible and promising.

• Journal of the Korean Society for Precision Engineering
• /
• v.13 no.6
• /
• pp.161-167
• /
• 1996

In five-axis milling, optimal CL-data (cutter location data) should be generated to have advantages over three-axis milling in terms of accuracy and efficiency. This paper presents an algorithm for generating collision-free CL-data for five-axis milling using potential energy method. By virtually charging the cutter and part surfaces with static electricity, global collision as wells as local interference is eliminated. Additionally, machining efficiency is improved by minimizing the curvature difference between the part surface and tool swept surface at a CC-point (cutter contact point) simultaneously.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.05a
• /
• pp.591-593
• /
• 2016

Device-to-device (D2D) communications underlaid cellular infrastructure is an competitive local area services technology to promote spectrum usage for next generation cellular networks. These potential can only be tap through efficient interference coordination. Previous works only concentrated on interference from D2D pairs whiles interference from CUs to D2D pairs were neglected. This work focus on solving uplink interference problem emanating from multiple CUs sharing its resource with multiple D2D pairs. The base station (BS) acting as a supervisor selfishly institute a pricing scheme to manage the interference it experience from D2D pairs based on its Quality of service (QoS) requirement. D2D pairs following the supervisor make power allocation decisions considering the price from the BS in a non-cooperative game fashion. In order for the D2D pairs to also meet their QoS requirement, they suggest a price to the BS called discount price which reflects the interference they receive from the CUs. Finally, we analyze the proposed approach.