• Title/Summary/Keyword: Synchronization

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An Enhanced AGC Structure and P-SCH Detection Method for Initial Cell Search in 3GPP LTE FDD/TDD Dual Mode Downlink Receiver (3GPP LTE FDD/TDD 듀얼 모드 하향 링크 수신기의 초기 셀 탐색을 위한 개선된 AGC 구조 및 P-SCH 검출 기법)

  • Chung, Myung-Jin;Jang, Jun-Hee;Choi, Hyung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.3C
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    • pp.302-313
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    • 2010
  • In this paper, we propose an enhanced AGC (Automatic Gain Control) structure and P-SCH detection method for initial cell search in 3GPP (3rdGenerationPartnershipProject) LTE (Long Term Evolution) FDD(Frequency Division Duplex) / TDD (Time Division Duplex) dual mode system. Since TDD frame structure consists of uplink subframe and downlink subframe, conventional AGC structure causes P-SCH detection performance degradation by increase of AGC variation due to signal power difference between uplink and downlink subframe. Also, P-SCH detection performance is degraded by distortion of P-SCH correlation characteristic in frequency offset and multipath fading channel environments. Therefore, we propose an AGC structure which can minimize P-SCH detection performance degradation with stable operation in 3GPP LTE TDD mode as well as FDD mode. Also we propose a P-SCH detection method which can reduce distortion of correlation chareteristics in frequency offset and multipath fading environments and obtain good P-SCH detection performance. Simulation results show that the proposed AGC structure and P-SCH detection method have stable AGC operation and excellent P-SCH detection performance for 3GPP LTE TDD / FDD dual mode downlink receiver in various channel environments.

Consideration of Roman Character in KS × 1001 Code System for Information Interchange considered AMI/HDB-3 and HDLC FLAG (AMI/HDB-3 회선부호화 및 HDLC FLAG를 고려한 KS × 1001 정보 교환용 로마문자 부호체계고찰)

  • Hong, Wan-Pyo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.7
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    • pp.1017-1023
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    • 2013
  • Datacommunications transmit the source codes that are coded in information devices, such as computer to the transmission line by means of the line coded signal. AMI method is applied to the line coding method to transmit the signal for long distance. The disadvantage of the AMI method is to loss the bit synchronization when consecutive binary bit '0' over 4ea is coming into line coder. The scrambling technique is used to overcome the problem. The HDB-3 scrambling method is used in Korea standard which standard in ITU-T. When the HDB-3 technology is used. the method should convert the consecutive bit '0' over 4ea to certain bits format. As a result, when there are many such kind of '0' bit stream in source codes, data transmission efficiency will be decreased to treat in line coder, etc. This paper is directed to study the Roman character code system in $KS{\times}1001$, Korea standard for information exchange code in datacommunication systems. Based on the study result, this paper proposed the maximum optimized Roman character code system. In the study, Character coding rule for $4{\times}4$bits and the statistical data for roman character using frequency were considered to simulate. The paper shows the result that when the proposed new roman character coding system is applied to use, the data transmission efficiency could be increased to about 134% compared to existing code system.

A Cell Selection Technique Considering MIMO Precoding (MIMO 프리코딩을 고려한 셀 탐색 기법)

  • Kim, Han Seong;Hong, Tae Howan;Cho, Yong Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37A no.12
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    • pp.1076-1084
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    • 2012
  • In the CS/CB(Coordinated Scheduling/Beamforming) scheme, the cell edge user throughput is increased by selecting MIMO (Multiple Input Multiple Output) precoders which can minimize the interferences from adjacent base stations (BSs). However, in current LTE(Long Term Evolution) systems, the serving cell is selected in the initialization stage by using the synchronization signals and cell specific reference signals transmitted by adjacent BSs with a single antenna. The selected BS in the initialization stage may not be the best one since the MIMO precoding gain has not been considered in the cell selection stage. In this paper, a new cell selection technique is proposed for LTE systems with MIMO precoder by taking into account the effect of the precoder in the initialization stage. The proposed technique enables a user equipment (UE) in the cell boundary to select the serving BS by using the information (channel rank, effective channel capacity, and effective SINR(Signal to Interference plus Noise Ratio)) acquired from cell specific reference signals of candidate BSs. It is verified by computer simulation that the proposed technique can increase the channel capacity significantly in the multi-cell environments, compared with the conventional CS/CB scheme.

Concurrency Control Using the Update Graph in Replicated Database Systems (중복 데이터베이스 시스템에서 갱신그래프를 이용한 동시성제어)

  • Choe, Hui-Yeong;Lee, Gwi-Sang;Hwang, Bu-Hyeon
    • The KIPS Transactions:PartD
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    • v.9D no.4
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    • pp.587-602
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    • 2002
  • Replicated database system was emerged to resolve the problem of reduction of the availability and the reliability due to the communication failures and site errors generated at centralized database system. But if update transactions are many occurred, the update is equally executed for all replicated data. Therefore, there are many problems the same thing a message overhead generated by synchronization and the reduce of concurrency happened because of delaying the transaction. In this paper, I propose a new concurrency control algorithm for enhancing the degree of parallelism of the transaction in fully replicated database designed to improve the availability and the reliability. To improve the system performance in the replicated database should be performed the last operations in the submitted site of transactions and be independently executed update-only transactions composed of write-only transactions in all sites. I propose concurrency control method to maintain the consistency of the replicated database and reflect the result of update-only transactions in all sites. The superiority of the proposed method has been tested from the respondence and withdrawal rate. The results confirm the superiority of the proposed technique over classical correlation based method.

Virtual Target Overlay Technique by Matching 3D Satellite Image and Sensor Image (3차원 위성영상과 센서영상의 정합에 의한 가상표적 Overlay 기법)

  • Cha, Jeong-Hee;Jang, Hyo-Jong;Park, Yong-Woon;Kim, Gye-Young;Choi, Hyung-Il
    • The KIPS Transactions:PartD
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    • v.11D no.6
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    • pp.1259-1268
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    • 2004
  • To organize training in limited training area for an actuai combat, realistic training simulation plugged in by various battle conditions is essential. In this paper, we propose a virtual target overlay technique which does not use a virtual image, but Projects a virtual target on ground-based CCD image by appointed scenario for a realistic training simulation. In the proposed method, we create a realistic 3D model (for an instructor) by using high resolution Geographic Tag Image File Format(GeoTIFF) satellite image and Digital Terrain Elevation Data (DTED), and extract the road area from a given CCD image (for both an instructor and a trainee). Satellite images and ground-based sensor images have many differences in observation position, resolution, and scale, thus yielding many difficulties in feature-based matching. Hence, we propose a moving synchronization technique that projects the target on the sensor image according to the marked moving path on 3D satellite image by applying Thin-Plate Spline(TPS) interpolation function, which is an image warping function, on the two given sets of corresponding control point pair. To show the experimental result of the proposed method, we employed two Pentium4 1.8MHz personal computer systems equipped with 512MBs of RAM, and the satellite and sensor images of Daejoen area are also been utilized. The experimental result revealed the effective-ness of proposed algorithm.

Superovulation Response after Follicular Wave Synchronization with Follicular Aspiration by Ultrasonography in HanWoo I. Effect of Follicular Aspiration on Ovarian Response Following Superovulation (과배란 처치시 우세난포 조절에 의한 한우 수정란 생산성 향상에 관한 연구 I. 우세난포 처리에 따른 난소반응)

  • 이병천;이동원;신수정;박종임;황우석
    • Journal of Embryo Transfer
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    • v.14 no.3
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    • pp.203-210
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    • 1999
  • In this stuyd, the effect of the dominant follicle aspiration for the superovulatory response in HanWoo was investigated. The criterion for the presence or absence of a dominant follicle based on their morphological examination. The dominant follicle was aspirated 48hr before the onset of superovulation treatment by 6.5MHz convex probe connected with a carrier and superovulation induced by FSH (Super-Ov Tyrer, Texas, U.S.A) adminstered twic a day s.c. over 4 day in a decreasing regimen. From 13 HanWoo scanned daily to determine the presence and growth of the dominant follicle, its an average diameter of 15.4mm was measured and an average diameter of corpora lutea was 18.7mm on day of follicular aspiration. In the experiment, a follicular remove by ultrasound-guided aspiration, the ovarian response was significantly enhanced when animals were superovulated in the aspiation of a dominant follicle compare with animals superovulated non-aspiration of a dominat follicle. In the aspiration of a dominant follicle donors yieleded more corpora lutea(14.4$\pm$4.7 vs 8.6$\pm$3.4) and transferable embryos(8.9$\pm$4.2 vs 5.4$\pm$2.7) than control. In cows in which the dominant follicle had been aspirated under sonographical control 2 days before superovuation, the number of corpus lutea and transferable embryos were significantly enhanced compared with animals superovulated in the presence of a dominant follicle (14.4$\pm$4.7 vs 6.9$\pm$2.7, ; 8.9$\pm$4.2 vs 3.3$\pm$1.6). After 7 days of artificial insemination, the embryos at 7 days were cllected by uterine flushing after dominant follicle insemination, the embryos at 7 days were collected by uterine flushing after dominant follicle aspiration and superovulation treatment, and evaluated their quality by morphological criteria. Sixteen embryos with excellent and good grade were transferred into 8 recipient cows. Six pregnancies were identified at 60 and 120 days of gestation by rectal palpations. In conclusion, the present study showed that 1) the presence or absence of a dominant follicle signficicnatly affects superovulatory responses, and 2) ultrasound-guided follicular aspiration of the dominant follicle and superovuation treatment provides an accurate and procedure to increase ovarian responses in HanWoo.

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Transplantation and Production of OPU Derived Hanwoo IVP Embryos (OPU 유래 한우 수정란 생산 및 이식)

  • Jin, Jong-In;Choi, Byung-Hyun;Kim, Seong-Su;Jo, Hyun-Tae;Sun, Du-Won;Lim, Hyun-Tae;Lee, Jung-Gyu;Min, Chan-Sik;Kong, Il-Keun
    • Journal of Embryo Transfer
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    • v.29 no.3
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    • pp.273-281
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    • 2014
  • This study was carried out to establish the system of OPU derived embryo production, management of recipients as well as offspring production. OPU derived embryo production system was carried out of aspiration of immature oocytes 2 times per week, total 24 times for 3 months by an ultrasonographic guided follicular aspiration system and then produced in vitro-produced blastocysts by in vitro maturation, fertilization and culture system. This work was collected total 13,866 oocytes, average $8.2{\pm}4.5$ oocytes per session and 8,170 G1 + G2 grade oocytes, average 4.8 oocytes per session by 1,692 times session of total 71 donors for 4 years from 2010 to 2013. The rate of cleavage and blastocyst developmental competence were obtained 11,825 (85.3%) and 5,032 (36.3%) that was $7.0{\pm}3.8$ cleaved embryos and $3.0{\pm}2.5$ blastocysts per session. OPU derived embryo transfer were taken place in 2, 4, 6 and 7 local governments at 2010, 2011, 2012 and 2013 for 4 years and pregnancy rate were obtained 41.2, 43.9, 46.5 and 49.7% in each years. It means that pregnancy rate was continuously improved according of every year for 4 years. Pregnancy rate was significantly different according to individual local government in which was 62.7% in B, but 24.2% in F at 2012. Paternity identification was carried out total 26 offspring in C local government of 2012 and then confirmed 100% agreement of its analysis. In conclusion, the results obtained the possibility of mass production of elite cow embryos as well as offspring by OPU derived embryo production system, of which could be decreased the required time of genetic improvement.

Effect of KNO3 Priming on Various Properties of Kenaf Seed under Non-Saline and Saline Conditions

  • Lee, In-Sok;Kang, Chan-Ho;Lee, Ki-Kwon
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.62 no.4
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    • pp.373-381
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    • 2017
  • The main objective of this study was to increase the germination percentage of kenaf seeds with less number of times under non-saline and saline conditions. Therefore, the first goal was to assess the response of kenaf seeds to NaCl. The second goal was to evaluate the effects of $KNO_3$ on kenaf seed germination. The germination percentage exhibited a decreasing tendency in germination rate. Plant dry weight was approximately 0.2 g in all treatments at 5 days after germination. As time passed, the electrical conductivity (EC) value of hydro-priming (HP) consistently increased by 8.7 mS/cm at 24 hours of immersion. However, seeds primed with $KNO_3$ showed no difference in EC values even as times passed. Regarding the priming effect, priming in 100 mM $KNO_3$ concentration for 12 hours increased germination up to 85% in $H_20$ solution and in 0 mM $KNO_3$ concentration upto 73.8% under 0.3% NaCl solution, compared to that of Control. Germination synchronization, shoot length, and leaf unfolding of primed seeds were greater than those of the Control. In addition, main root and hair roots appeared more rapidly in the treated seeds and were more abundant compared to that of the Control. The T50 (times to reach 50% of the final germination percentage) of the Control in both $H_20$ and 0.3% NaCl solutions was 18 and 22 hours, respectively. However, when treated $KNO_3$ priming (0 to 100 mM) in $H_20$ and 0.3% NaCl solution, 9 hours was sufficient to reach T50. Primed (hydro-priming and $KNO_3$) seeds had a lower MDG (mean days untill germination; 0.6-0.62) compared to that of the Control (1.13-1.31) in $H_20$ and 0.3% NaCl solutions. Regarding dry weight of plants after priming, an increasing tendency after the priming treatment in the H20 solution was observed. Furthermore, no significant difference in plant dry weight under 0.3% NaCl stress was observed between the Control and primed seeds. Taken together, the results suggest that 50-100 mM $KNO_3$ priming for 24 hours optimize seed germination rate in less number of times of exposure with great vigor. Therefore, it is recommended for kenaf seed invigoration before planting.

Effects of Recipient Oocytes and Donor Cells Condition on in Vitro Development of Cloned Embryos after Interspecies Nuclear Transfer with Caprine Somatic Cell (산양의 이종간 핵이식에 있어서 수핵난자에 따른 공여세포의 조건이 핵이식란의 체외발달에 미치는 영향)

  • 이명열;박희성
    • Reproductive and Developmental Biology
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    • v.28 no.1
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    • pp.13-20
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    • 2004
  • This study was conducted to investigate the developmental ability of caprine embryos after somatic cell interspecies nuclear transfer. Donor cells were obtained from an ear-skin biopsy of a caprine, digested with 0.25% trypsin-EDTA in PBS, and primary fibroblast cultures were established in TCM-199 with 10% FBS. After maturation, expanded cumulus cells were removed by vigorous pipetting in the presence of 0.3% hyaluronidase. The matured oocytes were dipped in D-PBS plus 10% FBS+7.5 $\mu\textrm{g}$/ml cytochalasin B and 0.05 M sucrose. The reconstructed oocytes were electrically fused with donor cells in 0.3 M mannitol fusion medium. After the electofusion, embryos were activated by electric stimulation. Interspecies nuclear transfer embryos with bovine cytoplasts were cultured in TCM-199 medium supplemented with 10% FBS including bovine oviduct epithelial cells for 7∼9 day. On the other hand, the NT embryos with porcine cytoplasts were cultured in NCSU-23 medium supplemented with 10% FBS for 6∼8 day at $39^{\circ}C, 5% CO_2$ in air. In caprine-bovine NT embryos, the cleavage(2-cell) rate was 36.8% in confluence and 43.8% in serum starvation. The developmental rate of morula- and blastocyst-stage embryos was 0.0% in confluence and 18.8% in serum starvation. In caprine-porcine NT embryos, the cleavage(2-cell) rate was 76.7% in confluence and 66.7% in serum starvation. The developmental rate of morula and blastocyst stage embryos was 3.3% in confluence and 3.0% in serum starvation, and no significant difference was observed in synchronization treatment between donor cells. In caprine-bovine NT embryos, the cleavage(2-cell) rate of cultured donor cells was 30.8% and 17.6% in 5∼9 and 10∼14 passage(P<0.05). The developmental rate of morula and blastocyst stage embryos were significantly higher(P<0.05) in 5∼9 passage(23.1%) than in 10∼14 passage(0.0%) of cultured donor cells. In caprine-porcine NT embryos, the cleavage rate was significantly higher(P<0.05) in 5∼9 passage(86.7%) than in 10∼14 passage(50.0%) of cultured donor cells. The developmental rate of morula and blastocyst stage embryos were 3.3 and 0.0% in 5∼9 and 10∼14와 passage of cultured donor cells. In caprine-bovine NT embryos, the developmental rate of morula and blastocyst stage embryos were 22.6% in interspecies nuclear transfer, 33.9% in in vitro fertilization and 28.1% in parthenotes, which was no significant differed. The developmental rate of morula and blastocyst stage embryos with caprine-porcine NT embryos were lower(P<0.05) in interspecies nuclear transfer(5.1%) than in vitro fertiltzation(26.9%) and parthenotes(37.4%).

Effect of Administration of Gonadotropin and Scheduled Fixed-time Insemination on Onset of Estrus and Reproductive Performance in Lactating Sows (포유중인 모돈에서 성선자극호르몬 투여 및 예정시각 인공수정이 발정재귀 및 번식성적에 미치는 영향)

  • Ryu, J.W.;Cho, K.H.;Son, J.H.;Kim, Y.S.;Chung, K.H.;Kim, I.C.
    • Journal of Animal Science and Technology
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    • v.49 no.4
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    • pp.451-458
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    • 2007
  • This study was to investigate the effectiveness of pre-weaning injection of gonadotropin and scheduled fixed-time insemination on sow fertility. Sows were randomly assigned to receive gonadotropin 2 days before weaning, 1 day after weaning or none as control. In gonadotropin treated groups, half of sows were inseminated twice at 24 and 36 hours after onset estrus and half of sows were inseminated twice at scheduled fixed-time. Weaning to onset of estrus was the shortest in lactating sows injected with gonadotropin prior to weaning. Liter size was significantly higher in AI groups after detection of estrus, compared to fixed-time AI group. Results of these experiments indicated that injection of gonadotropin in lactating sows could initiate the final follicular development, and has potential to enhance the reintegration of estrus. Further researches are needed to define the relationship between reduced interval of wean to onset estrus and enhanced fertility in lactating sows.