• Title/Summary/Keyword: block of spread

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A Plant Breeder's View on H5N1

  • Kim, Soon-Kwon
    • Korean Journal of Breeding Science
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    • v.40 no.2
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    • pp.106-112
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    • 2008
  • International conferences to block the spread of Avian bird flu occurred in Beijing, 2006 and others warned of the seriousness of the H5N1 strain. The meetings succeeded in generating billions of dollars from USA, EU and World Bank. Migratory birds seem to play a major role in the spread of the aggressive strain globally from Asia to Europe and Africa. Experiences of tolerance breeding of maize (Zea mays L.) for four decades against 20 biotic stresses suggest that the prime cause of the occurrence of H5N1 strain was due to the human beings' counter-efforts against nature. Excessive use of chemicals (spray and injection) in the commercial poultry farms had created high selection pressure on virus. The new strain had mutated for survival. Attempting to eliminate the virus by chemicals for 100% control is a dangerous way to control biotic stresses. This can create more aggressive strains. A solution would be to build up tolerability of the commercial animals against the virus. Improvement of poultry cage environments and respect for nature must be integrated. Potential foes must be watched.

A Spread Random Interleaver based Efficient DES Algorithm for Personal Cloud Computing Environments (개인 클라우드 컴퓨팅 환경을 위한 스프레드 랜덤 인터리버 기반의 효율적인 DES 알고리즘)

  • Chung, Yeon Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.1
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    • pp.41-48
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    • 2013
  • An efficient encryption algorithm based on the Data Encryption Standard (DES) for personal cloud computing environments is presented. The proposed algorithm improves data privacy, security and also encryption speed, compared with the triple DES. The improvement of the proposed algorithm stems from enhanced privacy inherent from the use of spread random interleaver in the place of the known substitution table for initial and final permutations in the DES algorithm. The simulation results demonstrate that the interleaver based DES (I-DES) is found to run faster than the triple DES algorithm and also offer improved security. The proposed algorithm also offers encryption for variable-length data using the Cipher Block Chaining (CBC).

Performance Comparison of Concatenated Codes with Different Inner Decoding Schemes in Frequency-Hopping Spread Spectrum Multiple-Access Channels (주파수 도약 대역확산 다중접속 채널에서 내 부호 복호화 기법에 따른 쇄상부호의 성능 비교)

  • Lee, Ye Hoon
    • Journal of Satellite, Information and Communications
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    • v.9 no.2
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    • pp.114-118
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    • 2014
  • In this paper, we analyze the performance of a concatenated code with two different inner decoding schemes. One is the error-detecting inner decoding, and the other is the error-detecting-and-correcting inner decoding scheme. We compare the performances of the two decoding schemes for finite and infinite block length cases when the concatenated code is applied to slow frequency-hopping spread-spectrum multiple access (FH-SSMA) communication systems.

Design of a Whitening Block Module for Minimizing DC Bias in Wireless Communications (무선 통신에서 DC 바이어스를 최소화하는 화이트닝 블록 설계)

  • Moon, San-Gook
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.10a
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    • pp.673-676
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    • 2008
  • In wireless communications such as Bluetooth, Baseband should be able to minimize the DC bias of the data which passed the modem interface of either transmitter or receiver for the reliability of the circuit and the integrity of the data. The transmitter scrambles the data to send randomly to the error correction block and the receiver recovers the randomly spread data as they have been. To design the whitening block, it is important to select the prime polynomial for the filtering. In this paper, we designed a optimal whitening block using the prime polynomial $g(D)=D^7+D^4+1$ for hardware and area efficiency. The proposed hardware whitening block was described and verified using Verilog HDL and later to be automatically synthesized. The synthesized whitening block operated at 40Mhz normal clock speed of the target baseband microcontroller.

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A Clinical Evaluation of Repeated Splanchic Nerve Block (내장신경 반복차단예에 대한 임상적 연구)

  • Sung, Nak-Soon;Yoon, Duck-Mi;Oh, Hung-Kun
    • The Korean Journal of Pain
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    • v.3 no.2
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    • pp.108-118
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    • 1990
  • Splanchnic nerve block (SNB) is performed to relieve intractable upper abdominal pain caused by carcinoma of the upper G-I tract. Not all patients achieve satisfactory pain relief; therefore, a second or third nerve block trial may need to be performed. In this study, an attempt was made to analyze the possible factors which might affect the result of repeated SNB in 42 the patients among 264 patients who received SNB at Severance Hospital during the period from January 1985 to December 1989. The results are as follows: 1) Among the 42 patients, including 30 males and 12 females, the fifties and forties were the major age groups. 2) Among the underlying diseases, stomach cancer was the most common (18 cases) and pancreatic cancer was next (14 cases). 3) The main locations of pain were the upper abdomen, epigastrium and entire abdomen in decreasing order. 4) Among the thirty-nine cases of first SNB combined with ascites, 13 cases received a repeat block, 81.0% of whom had had metastatic lesion. 5) There were 54.2% who had had single or combined treatment, operation, chemotherapy or radiotherapy before SNB. 6) Twently seven cases (64.3%) had received opioid medication for pain control. 7) In the 75% alcohol group, 11.7% of patients required a second block, and in the pure and 50% alcohol group, 9.6% of patients required a second block within two weeks of the first block. Three cases in both of these repeated block groups required a third block; representing 3.9%, of the 75% alcohol group and 1.6% of the pure and 50% alcohol group. 8) The volume of alcohol used was more than 16 ml bilaterally in both cases. 9) The points of the inserted needle were positioned in the upper and anterolateral part of the $L_1$ vertebra on both sides on the anteroposterior roentgenogram. The contrast media was spread upward along the anterior margin of the vertebral body and posteriorly in repeat block. The frequency of repeat block was higher in cases with ascites or metastasis. The instance of repeat block within 2 weeks of the first block was lower in the pure and 50% alcohol group than in the 75% alcohol group. Thus, alcohol concentration and patient status may be considered factors which influence the result of repeated SNB. We suggest early application of SNB in upper abdominal cancer patients.

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Metaverse Framework and Building Block (메타버스 프레임워크와 구성요소)

  • Kang, Young-myoung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.25 no.9
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    • pp.1263-1266
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    • 2021
  • The global Covid-19 pandemic has been accelerating the transition to the digital environment that enables providing consistent services without being affected by physical location or various circumstances. The Metaverse might be the representative realization reflecting this trend. In this paper, we introduce the potential core stacks consisting of the Metaverse framework in brief and explain why the open Metaverse framework is an adequate and reasonable design choice to support diverse platforms and multiple instances of the virtual world. Since the development of the open Metaverse framework is indeed in a very early stage, achieving technical completeness in each building block of the open Metaverse is crucial. Considering the expansion and spread of the Metaverse in the future, intensive standardization studies on the open Metaverse framework are exigent and indispensable.

An Optimum Paged Interleaving Memory by a Hierarchical Bit Line (계층 비트라이에 의한 최적 페이지 인터리빙 메모리)

  • 조경연;이주근
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.6
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    • pp.901-909
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    • 1990
  • With a wide spread of 32 bit personal computers, a simple structure and high performance memory system have been highly required. In this paper, a memory block is constructed by using a modified hierarchical bit line in which the DRAM bit line and the latch which works as a SRAM cell are integrated by an interface gate. And the new architecture memory DSRAM(Dynamic Static RAM) is proposed by interleaving the 16 memory block. Because the DSRAM works with 16 page, the page is miss ratio becomes small and the RAS precharge time which is incurred by page miss is shortened. So the DSRAM can implement an optimum page interleaving and it has good compatibility to the existing DRAMs. The DSRAM can be widely used in small computers as well as a high performance memory system.

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Edema and hematoma after local anesthesia via posterior superior alveolar nerve block: a case report

  • Marques, Aline Louise Nascimento;Figueroba, Sidney R.;Mafra, Marco Antonio Tridapalli;Groppo, Francisco Carlos
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.22 no.3
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    • pp.227-231
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    • 2022
  • Although rare, complications can occur with anesthetic procedures. The posterior superior alveolar nerve (PSAN) block anesthetic technique has a high success rate, but positive aspiration can cause bruising, transient diplopia, blurred vision, and temporary blindness in approximately 3% cases. When edema occurs, it is occasionally massive, especially in the infratemporal fossa, and the resulting hematoma is usually unsightly. A 20-year-old woman presented with massive edema followed by hematoma in the upper right jaw immediately after PSAN block administration, which subsequently spread to the oral mucosa. The patient did not report any complications during the anesthetic procedure. However, after the injection was administered, the patient experienced anesthetic sensations, which rapidly evolved to facial edema. There was mild pain, but without intraoral or extraoral bleeding. The patient was prescribed medicines and instructed to perform contrast therapy. Although hematomas and edema are rare, they are difficult to prevent. The choice of local anesthetic and appropriate application of the anesthetic technique can minimize their occurrence.

A study on the commercialization cause of 2nd class residential area in urban center (도시거점내 제2종 일반주거지역 상업화 확산과 원인 분석)

  • Yoon, Yong-Suk;Yang, Woo-Hyun
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 2011.04a
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    • pp.147-152
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    • 2011
  • The purpose of this study is to find out the commercialization cause of 2nd class residential area in urban center as basic research to protect urban residential area against the pressure of commercialization. Through the research that are based on literature, field survey and urban planning map, it analysed the commercialization cause of selected two sites under similar urban condition ; to be a nearby subway station and to be a famous commercial street in site, etc. The consequences of this study are summarized as follows ; First the distance between subway station and residential block and residential commercialization are in inverse proportion each other. Second, the corner lot of a block and the access street directly connected collector street are very important factors to spread commercialization to residential area. Finally, nevertheless first and second results, there is square zone which is very high rate of commercialization within one regardless the distance between subway and residential block. the maximum range of square zone is assumed about 250 meter based on case study.

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Performance of Block Error Probabilities of FS MC-CDMA System using BCH Coding Scheme in Slow Multipath Fading Channels (슬로우 다중경로 페이딩 채널환경에서 BCH 부호화기법을 이용한 FS MC-CDMA 시스템의 블록에러확률의 성능 개선)

  • Jin, Ze-Guang;Kang, Heau-Jo
    • Journal of Advanced Navigation Technology
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    • v.12 no.2
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    • pp.115-121
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    • 2008
  • In this paper, we analysis the error performance improvement of the FS MC-CDMA, whose information data are spread spectrum with direct sequences(DS), and each subband signal is transmitted using a subcarrier frequency, combining BCH code in Mobile communication channels which is characterized by Nakagami fading. The effect of co-channel interference on the block error performance is also studied in this paper. As a results of study, the coding techniques provides more efficient improvement than non-coding, but the coding techniques are required more band as many coding rate. Our study demonstrates that the system is combined coding techniques, the amount of improvement is capable of efficiently exploiting over the Nakagami fading.

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