• Title/Summary/Keyword: Buffer Function

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A Study on Application of Port Hinterland by a Space Port City Interface Characteristics (항만도시 인터페이스 공간특성에 의한 항만배후단지 활용방안)

  • Hwang, Sun Ah;Kim, Jong Gu;Hong, Ji Su
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.1
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    • pp.169-180
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    • 2016
  • The spaces of port and urban in a Port City have different space characteristics substantially, but those are required to be developed interdependently. Degradation and loss of the sense of place in the existing spaces caused by decline of natural function have an adverse effect on the revival of local economy as well as make worse image of the entire city. In some developed countries, therefore, many researches on the port spaces lagging behind the times due to changes of the characteristics and function of port spaces have been conducted continuously for a long time. This study aims at seeking a device how the domestic hinterland could be utilized as efficient spaces having the characteristics of outskirts space and port city interface through the application of characteristics of the interface space of port city, capable of playing a role as buffer zone between the port space and the city space.

The Study Active-based for Improvement of Reliablity In Mobile Ad-hoc Network (이동 애드혹 네트워크에서 신뢰성 향상을 위한 액티브 기반연구)

  • 박경배;강경인;유재휘;김진용
    • Journal of the Korea Society of Computer and Information
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    • v.7 no.4
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    • pp.188-198
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    • 2002
  • In this paper, we propose an active network to support reliable data transmission in the mobile ad-hoc network. The active network uses DSR(Dynamic Source Routing) protocol as its basic routing protocol, and uses source and destination nodes as key active nodes. For reliable improvement the source node is changed to source active node to add function that its buffer to store the last data with the flow control for data transmission per destination node. The destination node is changed to destination active node to add function that it requests the re-transmission for data that was not previously received by the destination active node with the flow control for data reception per source active node As the result of evaluation. we found the proposed active network guaranteed reliable data transmission with almost 100% data reception rate for slowly moving mobile ad-hoc network and with more 95% data reception rate, which is improvement of 3.5737% reception rate compared with none active network, for continuously fast moving mobile ad-hoc network.

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An Optimal Design of a TDMA Baseband Modem for Relay Protocol (중계 프로토콜을 위한 TDMA 기저대역 중계모뎀의 최적 설계)

  • Bae, Yongwook;Ahn, Byoungchul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.6
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    • pp.124-131
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    • 2014
  • This paper describes a design of an adaptive baseband modem based on TDMA(time division multiple access) with a relay protocol function for wireless personal area networks. The designed baseband modem is controlled by a master synchronization signal and can be configured a relay network up to 14 hops. For efficient data relay communications, the internal buffer design is optimized by implementing a priority memory bus controller to a single port memory. And the priority memory bus controller is also designed to minimize the number of synthesized logic gates. To implement the synchronization function of the narrowband TDMA relay communication, the number of gates has been reduced by dividing the frame synchronization circuits and the network slot synchronization circuits. By using these methods, the number of gates are used about 37%(34,000 gates) on Xilinx FPGA XC6SLX9 which has 90,000 gates. For the 1024-bit frame size with a 32-bit synchronization word, the communication reception rate is 96.4%. The measured maximum transmission delay of the designed baseband modem is 230.4 msec for the 14-hop relay communication.

Software Attack Detection Method by Validation of Flow Control Instruction’s Target Address (실행 제어 명령어의 목적 주소 검증을 통한 소프트웨어 공격 탐지 기법)

  • Choi Myeong-Ryeol;Park Sang-Seo;Park Jong-Wook;Lee Kyoon-Ha
    • The KIPS Transactions:PartC
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    • v.13C no.4 s.107
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    • pp.397-404
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    • 2006
  • Successful software attacks require both injecting malicious code into a program's address space and altering the program's flow control to the injected code. Code section can not be changed at program's runtime, so malicious code must be injected into data section. Detoured flow control into data section is a signal of software attack. We propose a new software attack detection method which verify the target address of CALL, JMP, RET instructions, which alter program's flow control, and detect a software attack when the address is not in code section. Proposed method can detect all change of flow control related data, not only program's return address but also function pointer, buffer of longjmp() function and old base pointer, so it can detect the more attacks.

Effect of Trolox C on Hypoxia/Reoxygenation-Induced Injury in Isolated Perfused Rat Liver

  • Lee, Sun-Mee;Cho, Tai-Soon
    • Archives of Pharmacal Research
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    • v.20 no.5
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    • pp.471-475
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    • 1997
  • Livers isolated from 18 hours fasted rats were subjected to N$_{2}$ hypoxia (for 45 min) followed by reoxygenation (for 45 min). The perfusion medium used was Krebs-Henseleit bicarbonate buffer (KHBB, pH 7.4). Lactate and alanine were added as gluconeogenic and ureagenic substrates and Trolox C was also added to perfusate. Oxygen consumption, lactate dehydrogenase (LDH), alanine transaminase (ALT), total glutathione, oxidized glutathione, bile flow, glucose and urea were measured. After hypoxia oxygen consumption significantly dropped but Trolox C had no influence on this decrease. ALT and LDH were significantly increased by hypoxia/reoxygenation. This increase was markedly attenuated in the presence of Trolox C. The total glutathione and oxidized glutathione efflux increased following hypoxia, which were prevented by the treatment of Trolox C. Bile flow rate decreased following hypoxia/reoxygenation but did not continue to decrease in the reoxygenation phase by Trolox C. Following hypoxia/reoxygenation glucose and urea releases decreased. Trolox C had no influence on inhibition of glucose and urea production. These results suggest that Trolox C protected the liver cells against hypoxia/reoxygenation injury, yielding further evidence for a causative role of oxidative stress in this model.

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Poly(Dimethylaminoethyl Methacrylate)-Based pH-Responsive Hydrogels Regulate Doxorubicin Release at Acidic Condition

  • Lee, Seung-Hun;You, Jin-Oh
    • Journal of the Korean Applied Science and Technology
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    • v.32 no.2
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    • pp.202-214
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    • 2015
  • Stimuli-responsive biomaterials that alter their function through sensing local molecular cues may enable technological advances in the fields of drug delivery, gene delivery, actuators, biosensors, and tissue engineering. In this research, pH-responsive hydrogel which is comprised of dimethylaminoethyl methacylate (DMAEMA) and 2-hydroxyethyl methacrylate (HEMA) was synthesized for the effective delivery of doxorubicin (Dox) to breast cancer cells. Cancer and tumor tissues show a lower extracellular pH than normal tissues. DMAEMA/HEMA hydrogels showed significant sensitivity by small pH changes and each formulation of hydrogels was examined by scanning electron microscopy, mechanical test, equilibrium mass swelling, controlled Dox release, and cytotoxicity. High swelling ratios and Dox release were obtained at low pH buffer condition, low cross-linker concentration, and high content of DMAEMA. Dox release was accelerated to 67.3% at pH 5.5 for 6-h incubation at $37^{\circ}C$, while it was limited to 13.8% at pH7.4 at the same time and temperature. Cell toxicity results to breast cancer cells indicate that pH-responsive DMAEMA/HEMA hydrogels may be used as an efficient matrix for anti-cancer drug delivery with various transporting manners. Also, pH-responsive DMAEMA/HEMA hydrogels may be useful in therapeutic treatment which is required a triggered release at low pH range such as gene delivery, ischemia, and diabetic ketoacidosis.

Modeling and Simulation of the Delay Time in Superconductive Multi-pole Hairpin type Filter (Superconductive Multi-pole Hairpin type Filter과 Delay Time 설계 및 실험)

  • 양재라;정구락;강준희
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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    • 2002.02a
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    • pp.135-137
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    • 2002
  • In the favor of adjusting microwave signal, Hairpin type Filter, which delay microwave signal enough to several nanosecond, is a key component. One of the main advantage in using Hairpin type Filter is a conveniency for equipping with Delay Module, and because of having a wide bandwidth, Hairpin type Filter can be designed to satisfy the most applications. In this work, we attempted to estimate the delay time in a superconductive hairpin type filter A software to synthesize even and odd order equiripple hairpin type filter has been developed. This software arbitrarily locate its transfer zeros making symmetric of asymmetric amplitude response and equalizing group delay. Borland C++ compiler has been used. The program was designed to run under MS-DOS, Window 98, Window 2000. The program optimizes the position of the transfer function zeros in order to fulfill the group delay specification masks. We designed and fabricated a hairpin type HTS 2-pole microstrip bandpass filter to operate at 5.8Ghz. The fabrication method was pulsed laser deposition and YBCO films were deposited on sapphire substrates with a Ce$O_{2}$ thin layer as a buffer layer. We also developed a new style hairpin type filter by using interdigitide inner-pole. Compared to the same size regular hairpin type filters, our filters had a lower center frequency.

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Fuzzy-based ABR Traffic Control Algorithm in VS/VD Switch (VS/VD 구조의 퍼지 기반 ABR 트래픽 제어에 관한 연구)

  • Park, Hyun;Jeong, Kwang-Il;Cheong, Myung-Soo;Chung, Kyung-Taek;Chon, Byoung-Sil
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.8
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    • pp.7-13
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    • 2002
  • In this paper, we propose an traffic control algorithm for efficient link utilization of ATM-ABR service based on fuzzy logic. The proposed algorithm, controls transmission rates of source according to switch buffer size and input cell tate by using the fuzzy rate . For this method we developed a model and algorithm of fuzzy traffic control method and fuzzy traffic controller which based on ER of VS/VD. For the fuzzy traffic controller, we also designed a membership function, fuzzy control rules, and a max-min inferencing method.

Seasonal Phosphorus Dynamics in a Forest Stream Water Following Different Harvests

  • Park, Byung Bae
    • Journal of Korean Society of Forest Science
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    • v.97 no.2
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    • pp.181-186
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    • 2008
  • Even small changes in phosphorus concentrations in stream water could cause eutrophication because of very low level of phosphorus concentrations in natural waters. I investigated the impact of strip cut and clear cut on phosphorus concentrations in stream water at the Hubbard Brook Experimental Forest and investigated stream water phosphorus concentrations as a function of flow rate and season (as well as cutting history). Mean phosphate concentrations in the control (undisturbed forest) increased $1.9{\mu}g\;L^{-1}\;to\;2.6{\mu}g\;L^{-1}$, while strip cut treatment increased phosphate concentrations in stream water $2.2{\mu}g\;L^{-1}\;to\;3.7{\mu}g\;L^{-1}$ during the same period. There was no significant effect of clear cut treatment on phosphate concentrations in stream water. No relationships were found between discharge rate and phosphate concentrations, but the magnitude of fluctuation were increased during two decades in undisturbed forest: $1-5{\mu}g\;L^{-1}$ from 1963 to 1975 and $1-12{\mu}g\;L^{-1}$ from 1983 to 1995. Based on this study, forest harvests with buffer zone will not make a problem by imported phosphate to cause eutrophication in natural water.

Highly Stabilized Protocrystalline Silicon Multilayer Solar Cells (고 안정화 프로터결정 실리콘 다층막 태양전지)

  • Lim Koeng Su;Kwak Joong Hwan;Kwon Seong Won;Myong Seung Yeop
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.06a
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    • pp.102-108
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    • 2005
  • We have developed highly stabilized (p-i-n)-type protocrystalline silicon (pc-Si:H) multilayer solar cells. To achieve a high conversion efficiency, we applied a double-layer p-type amorphous silicon-carbon alloy $(p-a-Si_{1-x}C_x:H)$ structure to the pc-Si:H multilayer solar cells. The less pronounced initial short wavelength quantum efficiency variation as a function of bias voltage proves that the double $(p-a-Si_{1-x}C_x:H)$ layer structure successfully reduces recombination at the p/i interface. It was found that a natural hydrogen treatment involving an etch of the defective undiluted p-a-SiC:H window layer before the hydrogen-diluted p-a-SiC:H buffer layer deposition and an improvement of the order in the window layer. Thus, we achieved a highly stabilized efficiency of $9.0\%$ without any back reflector.

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