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

• The KIPS Transactions:PartC
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• v.16C no.3
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• pp.317-324
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• 2009

In this paper, a 4-way Handshake protocol in the IEEE 802.11i is analyzed in terms of both security and reliability. It is shown that the 4-way Handshake protocol breaks down under some conditions due to a MIC (message integrity code) failure, and a solution to fix it is proposed. It is also proposed that a new 2-way Handshake protocol which is more secure and efficient than the 4-way Handshake protocol.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10c
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• pp.226-228
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• 2003

무선통신과 관련된 대표적인 프로토콜로써 Bluetooth, IEEE 802.11, HomeRF등이 있다. 이러한 프로토콜들을 이용한 제품들이 생산되면서, 동일한 환경에서 어느 프로토콜이 더 적합한지를 결정할 필요가 있다. 본 논문에서는 Bluetooth와 IEEE 802.11의 표준을 기반으로 무선 노트북이나 이동전화에서의 성능을 평가하고 그 결과를 보여준다.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1689-1691
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• 1999

The conduction characteristics of $Pr_6O_{11}$-based ZnO varistor were investigated. ZnO-$Pr_6O_{11}$-CoO-$Sm_2O_3$-based ZnO varistor were sintered at $1300^{\circ}C$ and $1350^{\circ}C$ in the addition range $0.0\sim2.0mol%$ $Sm_2O_3$, respectively. ZnO varistors which are added with 1.0mol% at each temperature exhibited best excellent conduction characteristics, namely the nonlinear exponent was 42.05 at $1300^{\circ}C$, 36.79 at $1350^{\circ}C$ and leakage current was $9.16{\mu}A$ at $1300^{\circ}C$, $11.7{\mu}A$ at $1350^{\circ}C$. Consequently, it is estimated that ZnO-$Pr_6O_{11}$-CoO-$Sm_2O_3$-based ZnO varistors, which $Sm_2O_3$ is added 1.0mol% is to be used as a basic composition of $Pr_6O_{11}$-based ZnO varistors.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.5
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• pp.733-738
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• 2013

Orthogonal Frequency Division Multiplexing (OFDM) based IEEE 802.11 a/g systems which are widely used in wireless LAN carry out channel estimation in one time per packet since the systems use only preamble. Whereas, midamble based channel estimation supports continuous channel estimation by tracking the channel state information periodically. Using IEEE 802.11p Wireless Access in Vehicular Environments (WAVE) system, we analyze the performance of the proposed system via practical measurements. Based on these results, practical issues on midamble based channel estimation are investigated.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.1
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• pp.41-48
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• 1994

A monitoring system for atmospheric CFC-12 and CFC-11 has been established at Mt. Kwan-Ak, Seoul National University (SNU) since July, 1991. The concentrations showed quite a large variation ranging from 495 to 37600 pptv (pptv=part per trillion, 10$^{-12}$ , v/v) for CFC-12 and from 233 to 12100 pptv for CFC-11 due to many local sources. However, monthly medians show rather limited ranges ; 553~765 pptv for CFC-12 and 301~431 pptv for CFC-11. Furthermore minimum concentrations could be defined relatively well during the whole period of observation. The regional background concentrations in 1993 near SNU wer estimated as 533 pptv for CFC-12 and 293 pptv for CFC-11. These values are very comparable to global averages in Northern Hemisphere, 523 pptv for CFC-12 and 287 pptv for CFC-11, reflecting the fast atmospheric mixing processes within the hemisphere. Examinations with meteorological parameters such as wind speed and direction suggest the possible measurement-window at SNU, appropriate for regional monitoring. Studies for improving the monitoring capability of the SNU station such as automation of the analysis system along with correlation with other meteorological parameters, are in progress at the present time.

• Journal of the Korea Society of Computer and Information
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• v.12 no.6
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• pp.229-234
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• 2007

In the IEEE 802.11 Wireless Local Area Networks (WLANs), network nodes experiencing collisions on the shared channel need to backoff for a random period of time. which is uniformly selected from the Contention Window (CW) This contention window is dynamically controlled by the Binary Exponential Backoff (BEB) algorithm. The BEB scheme suffers from a unfairness problem and low throughput under high traffic load. In this paper, I propose a new backoff algorithm for use with the IEEE 802.11 Distributed Coordination Function.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.91-94
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• 2007

In the IEEE 802.11 Wireless Local Area Networks (WLANs), network nodes experiencing collisions on the shared channel need to backoff for a random period of time, which is uniformly selected from the Contention Window (CW). This contention window is dynamically controlled by the Binary Exponential Backoff (BEB) algorithm. The BEB scheme suffers from a fairness problem and low throughput under high traffic load. In this paper, I propose a new backoff algorithm for use with the IEEE 802.11 Distributed Coordination Function.

• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.2
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• pp.185-189
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• 2001

Wild type Bacilus thuringiensis subsp. israelensis and B. sphaericus toxins have been used separately as active in ingredients for bacterial insecticides to control mosquito larvae due to their comparable toxicity to chemical insecticides. Cry11B, recently cloned from B. thuringiensis subsp. jegathesan, shows higher toxicity against three major species of mosquito larvae than Cry11A, one of the major component of B. thuringiensis subsp. israelensis inclusion body. To determine whether the combination of cry11B and B. sphaericus binary toxins is as toxic as B. thuringiensis subsp. israelensis parental strain, cry11B and B. sphaericus binary toxins genes were co-expressed as an operon using cytlA promoters/STAB-SD hybrid expression system in B. thuringiensis subsp. israelensis acrystalliferous strain 4Q7. However, unexpectedly, B. sphaericus binary toxins were barely produced, whereas relatively large amount of Cry11B was produced. When this strain was grown in four different media, NB+G and Peptonized Milk produced more toxin proteins and spores per unit of media than GYS and G-Tris. Toxicity of this strain against fourth instar Culex quinquefasciatus was ranged from of 8.3 to 45.7 ng/ml, with NB+G culture being the highest, and GYS culture was the lowest.

• Molecules and Cells
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• v.43 no.8
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• pp.705-717
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• 2020

While the growth factors like insulin initiate a signaling cascade to induce conformational changes in the mechanistic target of rapamycin complex 1 (mTORC1), amino acids cause the complex to localize to the site of activation, the lysosome. The precise mechanism of how mTORC1 moves in and out of the lysosome is yet to be elucidated in detail. Here we report that microtubules and the motor protein KIF11 are required for the proper dissociation of mTORC1 from the lysosome upon amino acid scarcity. When microtubules are disrupted or KIF11 is knocked down, we observe that mTORC1 localizes to the lysosome even in the amino acid-starved situation where it should be dispersed in the cytosol, causing an elevated mTORC1 activity. Moreover, in the mechanistic perspective, we discover that mTORC1 interacts with KIF11 on the motor domain of KIF11, enabling the complex to move out of the lysosome along microtubules. Our results suggest not only a novel way of the regulation regarding amino acid availability for mTORC1, but also a new role of KIF11 and microtubules in mTOR signaling.