• Title/Summary/Keyword: Parity Space

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Effective identification of dominant fully absorbing sets for Raptor-like LDPC codes

  • Woncheol Cho;Chanho Yoon;Kapseok Chang;Young-Jo Ko
    • ETRI Journal
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    • v.45 no.1
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    • pp.7-17
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    • 2023
  • The error-rate floor of low-density parity-check (LDPC) codes is attributed to the trapping sets of their Tanner graphs. Among them, fully absorbing sets dominantly affect the error-rate performance, especially for short blocklengths. Efficient methods to identify the dominant trapping sets of LDPC codes were thoroughly researched as exhaustively searching them is NP-hard. However, the existing methods are ineffective for Raptor-like LDPC codes, which have many types of trapping sets. An effective method to identify dominant fully absorbing sets of Raptor-like LDPC codes is proposed. The search space of the proposed algorithm is optimized into the Tanner subgraphs of the codes to afford time-efficiency and search-effectiveness. For 5G New Radio (NR) base graph (BG) 2 LDPC codes for short blocklengths, the proposed algorithm finds more dominant fully absorbing sets within one seventh of the computation time of the existing search algorithm, and its search-effectiveness is verified using importance sampling. The proposed method is also applied to 5G NR BG1 LDPC code and Advanced Television Systems Committee 3.0 type A LDPC code for large blocklengths.

Predicting Lympho-Vascular Space Invasion in Endometrial Cancers with Mucinous Carcinomatous Components

  • Ilker, Selcuk;Nilufer, Cetinkaya;Firat, Cuylan Zeliha;Bulent, Ozdal;Hatice, Bayramoglu;Tayfun, Gungor
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.10
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    • pp.4247-4250
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    • 2015
  • Objective: To determine the predictors of lympho-vascular space invasion (LVSI) in endometrial cancers which contain mucinous carcinomatous histology. Materials and Methods: Clinical and histopathological data of endometrial carcinomas with a mucinous carcinomatous component diagnosed between January 2007 and January 2014 at the Gynecologic Oncology Department of Zekai Tahir Burak Women's Health Education and Research Hospital were reviewed retrospectively. Results: Twelve patients (25.5%) were positive for LVSI and 35 (74.5%) patients were negative. Patients with LVSI were mostly staged higher than 1A. Mean age, BMI and parity were not significantly different between patient groups. Larger tumor diameter (${\geq}2cm$) (p=0.04) and elevated Ca125 and Ca-19.9 (p=0.01) levels were significant for predicting LVSI. We also found>1/2 myometrial invasion (p<0.001), cervical stromal involvement (p=0.002) and higher grade (2-3) (p=0.001) significant for predicting LVSI. In multivariate analysis we found only grade significant for predicting LVSI. Conclusions: Especially grade of tumor is a crucial factor for determining LVSI in endometrial cancers with mucinous carcinomatous components.

Lympho-Vascular Space Invasion Indicates Advanced Disease for Uterine Papillary Serous Tumors Arising from Polyps

  • Ilker, Selcuk;Elmas, Korkmaz;Emre, Ozgu;Mengu, Turker;Erkaya, Salim;Tayfun, Gungor
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.10
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    • pp.4257-4260
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    • 2015
  • Background: Uterine papillary serous tumors are rarely seen and behave aggressively. Our aim was to evaluate uterine papillary serous tumors arising from polyps. Materials and Methods: Clinicopathological data of patients with uterine serous cancer arising from a polyp at the Gynecological Oncology Department of Zekai Tahir Burak Women's Health Education and Research Hospital were reviewed retrospectively. Results: We analyzed patients according to FIGO 2009 staging system as stage 1A and higher than stage 1A (3 and 6, respectively). All the patients were postmenopausal. Mean CA-125, CA-19.9 and CA15.3 levels were elevated in higher than stage 1A group. However we did not find a statistical difference between age, parity, polyp size, CA-125, CA-15.3, CA-19.9 and CEA levels. Lympho-vascular space invasion (LVSI) showed predictivity for advanced disease (p=0.025). Conclusions: The histopathologic nature of uterine serous carcinoma is a unique entity. LVSI is a prognosticator for defining an advanced stage uterine papillary tumor.

Turbo Perallel Space-Time Processing System with LDPC Code in MIMO Channel for High-Speed Wireless Communications (MIMO 채널에서 고속 무선 통신을 위한 LDPC 부호를 갖는 터보 병렬 시공간 처리 시스템)

  • 조동균;박주남;황금찬
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.10C
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    • pp.923-929
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    • 2003
  • Turbo processing have been known as methods close to Shannon limit in the aspect of wireless multi-input multi-output (MIMO) communications similarly to wireless single antenna communication. The iterative processing can maximize the mutual effect of coding and interference cancellation, but LDPC coding has not been used for turbo processing because of the inherent decoding process delay. This paper suggests a LDPC coded MIMO system with turbo parallel space-time (Turbo-PAST) processing for high-speed wireless communications and proposes a average soft-output syndrome (ASS) check scheme at low signal to noise ratio (SNR) for the Turbo-PAST system to decide the reliability of decoded frame. Simulation results show that the suggested system outperforms conventional system and the proposed ASS scheme effectively reduces the amount of turbo processing iterations without performance degradation from the point of average number of iterations.

A Design of SSD Dedicated RAID System for Efficient Resource Management (효율적인 자원관리를 위한 SSD 전용 RAID 시스템 설계)

  • Hyun-Seob Lee
    • Journal of Internet of Things and Convergence
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    • v.10 no.2
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    • pp.109-114
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    • 2024
  • Enterprise storage systems that require high data reliability are applying RAID (Redundant Array of Independent Disks) systems to recover from data loss and failure. In particular, RAID 5 ensures space efficiency and reliability by distributing parity across multiple storage devices. However, when storage devices have different capacities, RAID is built based on the smallest capacity storage device, resulting in wasted storage space. Therefore, research is needed to solve this resource management problem. In this paper, we propose a method for RAID grouping of each independent NAND flash memory block in a RAID consisting of SSD (Solid State Disk) with external SSDs as well as internal SSDs. This method is divided into a policy for delivering block information inside SSDs to the RAID system and a policy for RAID grouping of physical addresses delivered from the RAID system. This method allows us to maintain a RAID that does not waste resources when SSDs of different capacities are grouped into RAID5. Finally, we demonstrate the effectiveness of the proposed method through experiments.

Model - Based Sensor Fault Detection and Isolation for a Fuel Cell in an Automotive Application (모델 기반 연료전지 스택 온도 센서 고장 감지 및 판별)

  • Han, Jaeyoung;Kim, Younghyeon;Yu, Sangseok
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.41 no.11
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    • pp.735-742
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    • 2017
  • In this study, an effective model-based sensor fault detection methodology that can detect and isolate PEM temperature sensors fault is introduced. In fuel cell vehicle operation process, the stack temperature affects durability of a fuel cell. Thus, it is important for fault algorithm to detect the fault signals. The major objective of sensor fault detection is to guarantee the healthy operations of the fuel cell system and to prevent the stack from high temperature and low temperature. For the residual implementation, parity equation based on the state space is used to detect the sensors fault as stack temperature and coolant inlet temperature, and residual is compared with the healthy temperature signals. Then the residuals are evaluated by various fault scenarios that detect the presence of the sensor fault. In the result, the designed in this study fault algorithm can detect the fault signal.

Production of Transgenic Cattle by Non-surgical Embryo Transfer (비외과적 수정란 이식에 의한 형질전환 소 생산 기술)

  • Uhm, Sang Jun;Yang, Jung Seok;Lee, Su Min;Joe, So Young;Heo, Young-Tae;Xu, Yong-Nan;Koo, Bon Chul;Cheong, Ki Soo;Kim, Kwang Jae;Kim, Ji Tae;Kim, Nam-Hyung;Ko, Dae-Hwan
    • Journal of Embryo Transfer
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    • v.28 no.3
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    • pp.169-175
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    • 2013
  • Recently, the transgenic animal production technique is very important for the production of bio-parmaceutical as animal bio-reactor system. However, the absence of survival evaluation in vitro produced transgenic embryos has been a problem of the low productivity of transgenic animal because of absent of pre-estimate of pregnancy after transgenic embryos transferred into recipient. Therefore, this study is conducted to improve efficiency of transgenic cattle production by improving the non-surgical embryo transfer (ET) method. Transgenic bovine embryos were produced by injection of feline immunodeficiency virus enhanced green fluorescent protein (FIV-EGFP) lentiviral vector into perivitelline space of in vitro matured MII stage oocytes, and then in vitro fertilization (IVF) was occured. Normal IVF and EGFP expressing blastocysts were transferred into recipients. Results indicated that 2 expanded blastocysts (34.7%) transferred group showed significantly (P<0.05) higher pregnancy rate than 1 expanded blastocyst (26.8%) transferred group. In case of parity of recipient, ET to heifer (34.9%) showed significantly (P<0.05) higher pregnancy rate than ET to multiparous recipient (21.2%). However, there are no significant differences of pregnancy rate between natural induced estrus and artificial induced estrus groups. Significantly (P<0.05) higher pregnancy rate was obtained from recipient group which have normal corpus luteum with crown group (34.8%) than normal corpus luteum without crown (13.6%). Additionally, treatment of $100{\mu}g$ Gn-RH injection to recipient group (38.6%) 1 day before ET significantly (P<0.05) increase pregnancy rate than non- Gn-RH injection to recipient group (38.6%). We also transferred 2 EGFP expressing expanded blastocysts to each 19 recipients, 7 recipients were pregnant and finally 5 EGFP transgenic cattle were produced under described ET condition. Therefore, our result suggested that transfer of 2 good-quality expanded blastocysts to $100{\mu}g$ of Gn-RH injected recipient which have normal corpus luteum with crown is feasible to produce transgenic cattle.