• Title/Summary/Keyword: Key recovery

Search Result 451, Processing Time 0.03 seconds

Preparation of High-Purity Urokinase Using Single-Step Hydrophobic Interaction Chromatography with p-Aminobenzamidine Ligand

  • Cao, Xue-Jun;Zhou, Jian-Hua;Huang, Zhen-Hui;Wu, Xing-Yan;Hur, Byung-Ki
    • Journal of Microbiology and Biotechnology
    • /
    • v.12 no.2
    • /
    • pp.196-203
    • /
    • 2002
  • A novel process for urokinase purification was studied using p-aminobenzamidine as the ligand and sepharose 4B as the matrix. The adsorption, washing, and elution conditions were optimized by an unusual method. An adsorption buffer containing 2.5 M NaCl and $1\%$ Tween 80 facilitated the adsorption of urokinase on the affinity media and prevented contaminants from binding to the p-aminobenzamidine affinity gel. It was found that $5\%$ Tween 80 removed most of the contaminants from the affinity column. A 0.2 M glycine elution buffer containing 0.5 M NaCl (pH 3.0) was found to have a strong elution ability with a high recovery and purity of urokinase. A crude urokinase material of231 IU/mg protein from human urine was purified to 124,300 IU/mg protein with a purification factor of 538 and yield of $86.7\%$. As a result, a high purity urokinase was obtained with only a single affinity chromatography step. The purification process was successfully scaled-up to a 2-1 chromatography column. The resulting urokinase eluate could be directly lyophilized, thereby complying with Chinese pharmacopoeia (1995 version) standards.

A Study Of The Acupuncture & Moxibustion Fix-a-Day Method In Seunjeongwon-Ilgi (『승정원일기(承政院日記)』를 통해 본 침구택일(鍼灸擇日) 활용 방법)

  • Oh, Jun-Ho;Cha, Wung-Seok;Kim, Nam-Il
    • The Journal of Korean Medical History
    • /
    • v.22 no.1
    • /
    • pp.15-24
    • /
    • 2009
  • The objective of this article is to analysis of Acupuncture & Moxibustion Fix-a-day Method (AMFDM;鍼灸擇日) shown in the Seunjeongwon-Ilgi(承政院日記). Through such inquisition, The practical application of AMFDM could be found. The authors used web database of Seunjeongwon-Ilgi(承政院日記) serviced by National Institution of Korea History. We searched the database twice. First, We check up the database using key words - '忌日', '吉日', '拘忌', '鍼', '針' and '灸'. Search words is "(忌日|吉 日|拘忌)&(鍼|針|灸)". Second, We check up the database using other key words - '瘟㾮', '爲吉', '爲受鍼吉'. 1. AMFDM was used whenever Royal Family was cared. Futhermore, Its application method was as same as medical documents said. 2. AMFDM in the Seunjeongwon-Ilgi consists of Taboo-day(忌日) and Favor-day(吉日). Taboo-day is classified into following 5 type. Weather, Moon phases, The 24 solar terms(節氣), Spirit-location(人神), KunJie-12-deity(建除十二神) and OnHuang-day(瘟㾮日). 3. Sometime contradiction was occurred when AMFDM was used. So AMFDM had the priority order. According to these's order, doctor picked up a date. 4. Doctor used AMFDM to control Interval of treatment. They thought that acupuncture treatment exhaust one's Qi(氣). Using AMFDM, they could give recovery period to patient.

  • PDF

A Study on Blended Inlet Body Design for a High Supersonic Unmanned Aerial Vehicle

  • You, Lianxing;Yu, Xiongqing;Li, Hongmei
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.17 no.2
    • /
    • pp.260-267
    • /
    • 2016
  • The design process of blended inlet body (BIB) for the preliminary design of a near-space high supersonic unmanned aerial vehicle (HSUAV) is presented. The mass flow rate and cowl area of inlet at a design point are obtained according to the cruise condition of the HSUAV. A mixed-compression axisymmetric supersonic inlet section with a fixed geometry reasonably matching the high supersonic cruise state is created by using the inviscid theory of aerodynamics. The inlet section is optimized and used as a baseline section for the BIB design. Three BIB concepts for the HSUAV are proposed, and their internal aerodynamic characteristics of inlet are evaluated using Euler computational fluid dynamics (Euler CFD) solver. The preferred concept is identified, in which the straight leading edge of the baseline HSUAV configuration is modified into the convex leading edge to accommodate the inlet and meet the requirements of the cowl area to capture the sufficient air flow. The total recovery of inlet for the preferred BIB concept and the aerodynamic characteristics of the modified HSUAV configuration are verified using Navier-Stokes computational fluid dynamics (NS CFD) solver. The validation indicates that the preferred BIB concept can meet both the requirements of the inlet and aerodynamic performance of the HSUAV.

Improving Accident Tolerance of Nuclear Fuel with Coated Mo-alloy Cladding

  • Cheng, Bo;Kim, Young-Jin;Chou, Peter
    • Nuclear Engineering and Technology
    • /
    • v.48 no.1
    • /
    • pp.16-25
    • /
    • 2016
  • In severe loss of coolant accidents (LOCA), similar to those experienced at Fukushima Daiichi and Three Mile Island Unit 1, the zirconiumalloy fuel claddingmaterials are rapidlyheateddue to nuclear decay heating and rapid exothermic oxidation of zirconium with steam. This heating causes the cladding to rapidly react with steam, lose strength, burst or collapse, and generate large quantities of hydrogen gas. Although maintaining core cooling remains the highest priority in accident management, an accident tolerant fuel (ATF) design may extend coping and recovery time for operators to restore emergency power, and cooling, and achieve safe shutdown. An ATF is required to possess high resistance to steam oxidation to reduce hydrogen generation and sufficient mechanical strength to maintain fuel rod integrity and core coolability. The initiative undertaken by Electric Power Research Institute (EPRI) is to demonstrate the feasibility of developing an ATF cladding with capability to maintain its integrity in $1,200-1,500^{\circ}C$ steam for at least 24 hours. This ATF cladding utilizes thin-walled Mo-alloys coated with oxidation-resistant surface layers. The basic design consists of a thin-walled Mo alloy structural tube with a metallurgically bonded, oxidation-resistant outer layer. Two options are being investigated: a commercially available iron, chromium, and aluminum alloy with excellent high temperature oxidation resistance, and a Zr alloy with demonstratedcorrosionresistance.Asthese composite claddings will incorporate either no Zr, or thin Zr outer layers, hydrogen generation under severe LOCA conditions will be greatly reduced. Key technical challenges and uncertainties specific to Moalloy fuel cladding include: economic core design, industrial scale fabricability, radiation embrittlement, and corrosion and oxidation resistance during normal operation, transients, and severe accidents. Progress in each aspect has been made and key results are discussed in this document. In addition to assisting plants in meeting Light Water Reactor (LWR) challenges, accident-tolerant Mo-based cladding technologies are expected to be applicable for use in high-temperature helium and molten salt reactor designs, as well as nonnuclear high temperature applications.

Distributed Access Privilege Management for Secure Cloud Business (안전한 클라우드 비즈니스를 위한 접근권한 분산관리)

  • Song, You-Jin;Do, Jeong-Min
    • The KIPS Transactions:PartC
    • /
    • v.18C no.6
    • /
    • pp.369-378
    • /
    • 2011
  • To ensure data confidentiality and fine-grained access control in business environment, system model using KP-ABE(Key Policy-Attribute Based Encryption) and PRE(Proxy Re-Encryption) has been proposed recently. However, in previous study, data confidentiality has been effected by decryption right concentrated on cloud server. Also, Yu's work does not consider a access privilege management, so existing work become dangerous to collusion attack between malicious user and cloud server. To resolve this problem, we propose secure system model against collusion attack through dividing data file into header which is sent to privilege manager group and body which is sent to cloud server. And we construct the model of access privilege management using AONT based XOR threshold Secret Sharing, In addition, our scheme enable to grant weight for access privilege using XOR Share. In chapter 4, we differentiate existing scheme and proposed scheme.

Sparse reconstruction of guided wavefield from limited measurements using compressed sensing

  • Qiao, Baijie;Mao, Zhu;Sun, Hao;Chen, Songmao;Chen, Xuefeng
    • Smart Structures and Systems
    • /
    • v.25 no.3
    • /
    • pp.369-384
    • /
    • 2020
  • A wavefield sparse reconstruction technique based on compressed sensing is developed in this work to dramatically reduce the number of measurements. Firstly, a severely underdetermined representation of guided wavefield at a snapshot is established in the spatial domain. Secondly, an optimal compressed sensing model of guided wavefield sparse reconstruction is established based on l1-norm penalty, where a suite of discrete cosine functions is selected as the dictionary to promote the sparsity. The regular, random and jittered undersampling schemes are compared and selected as the undersampling matrix of compressed sensing. Thirdly, a gradient projection method is employed to solve the compressed sensing model of wavefield sparse reconstruction from highly incomplete measurements. Finally, experiments with different excitation frequencies are conducted on an aluminum plate to verify the effectiveness of the proposed sparse reconstruction method, where a scanning laser Doppler vibrometer as the true benchmark is used to measure the original wavefield in a given inspection region. Experiments demonstrate that the missing wavefield data can be accurately reconstructed from less than 12% of the original measurements; The reconstruction accuracy of the jittered undersampling scheme is slightly higher than that of the random undersampling scheme in high probability, but the regular undersampling scheme fails to reconstruct the wavefield image; A quantified mapping relationship between the sparsity ratio and the recovery error over a special interval is established with respect to statistical modeling and analysis.

Isolation and Antimicrobial Susceptibility of Nontuberculous Mycobacteria in a Tertiary Hospital in Korea, 2016 to 2020

  • Keun Ju Kim;Seung-Hwan Oh;Doosoo Jeon;Chulhun L. Chang
    • Tuberculosis and Respiratory Diseases
    • /
    • v.86 no.1
    • /
    • pp.47-56
    • /
    • 2023
  • Background: There is a global increase in isolation of nontuberculous mycobacteria (NTM). The aim of the study was to analyze longitudinal trends of NTM identification and pattern of antimicrobial susceptibility testing. Methods: NTM recovery rates, distribution of NTM species identification, and antimicrobial susceptibility pattern of NTM at Pusan National University Yangsan Hospital between January 2016 and December 2020 were retrospectively analyzed. Results: A total of 52,456 specimens from 21,264 patients were submitted for mycobacterial culture, of which 2,521 from 1,410 patients were NTM positive over five years (January 2016 to December 2020). NTM isolation showed an increasing trend from 2016 to 2020 (p<0.001, test for trend) mainly caused by Mycobacterium avium complex. The vast majority of M. avium complex were susceptible to key agents clarithromycin and amikacin. For Mycobacterium kansasii, resistance to rifampin and clarithromycin is rare. Amikacin was the most effective drug against Mycobacterium abscessus subspecies abscessus and Mycobacterium subspecies massiliense. Most of M. subspecies massiliense were susceptible to clarithromycin, while the majority of M. abscessus subspecies abscessus were resistant to clarithromycin (p<0.001). Conclusion: There was an increasing trend of NTM isolation in our hospital. Resistance to key drugs was uncommon for most NTM species except for M. abscessus subspecies abscessus against clarithromycin.

Damage characterization of hard-brittle rocks under cyclic loading based on energy dissipation and acoustic emission characteristics

  • Li, Cheng J.;Lou, Pei J.;Xu, Ying
    • Geomechanics and Engineering
    • /
    • v.31 no.4
    • /
    • pp.365-373
    • /
    • 2022
  • In order to investigate the damage evolution law of rock specimens under cyclic loading, cyclic loading tests under constant loads with different amplitudes were carried out on limestone specimens with high strength and brittleness values using acoustic emission (AE) technology and the energy evolution and AE characteristics were evaluated. Based on dissipated energy density and AE counts, the damage variable of specimen was characterized and two damage evolution processes were analyzed and compared. The obtained results showed that the change of AE counts was closely related to radial deformation. Higher cyclic loading values result in more significant radial strain of limestone specimen and larger accumulative AE counts of cyclic loading segment, which indicated Felicity effect. Regarding dissipated energy density, the damage of limestone specimen was defined without considering the influence of radial deformation, which made the damage value of cyclic loading segment higher at lower amplitude loads. The damage of cyclic loading segment was increased with the magnitude of load. When dissipated energy density was applied to define damage, the damage value at unloading segment was smaller than that of AE counts. Under higher cyclic loading values, rocks show obvious damage during both loading and unloading processes. Therefore, during deep rock excavation, the damages caused by the deformation recovery of unloading rocks could not be ignored when considering the damage caused by abutment pressure.

Differential Cryptanalysis on 15-Round IIoTBC Block Cipher Utilizing Cancellation of Differences (차분의 상쇄를 이용한 15-라운드 IIoTBC 블록암호에 대한 차분공격)

  • Wonwoo Song;Jaewon Seo;Yongjin Jeon;Jongsung Kim
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.34 no.4
    • /
    • pp.569-575
    • /
    • 2024
  • The 64-bit block cipher IIoTBC is an encryption algorithm designed for the security of industrial IoT devices and uses an 128-bit secret key. The IIoTBC's encryption algorithm varies depending on whether the MCU size used in IoT is 8-bit or 16-bit. This paper deals with a differential attack on IIoTBC when the MCU size is 8-bit. It attacks 15-round out of the entire 32-round using IIoTBC's 14-round differential characteristic. At this time, the number of required plaintexts and encryption are 257 and 2122.4, respectively. The differential characteristic presented in this paper has a longer round than the existing 13-round impossible differential characteristic, and the attack using this is the result of the first key recovery attack on IIoTBC.

A 5.4Gb/s Clock and Data Recovery Circuit for Graphic DRAM Interface (그래픽 DRAM 인터페이스용 5.4Gb/s 클럭 및 데이터 복원회로)

  • Kim, Young-Ran;Kim, Kyung-Ae;Lee, Seung-Jun;Park, Sung-Min
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.44 no.2
    • /
    • pp.19-24
    • /
    • 2007
  • With recent advancement of high-speed, multi-gigabit data transmission capabilities, serial links have been more widely adopted in industry than parallel links. Since the parallel link design forces its transmitter to transmit both the data and the clock to the receiver at the same time, it leads to hardware's intricacy during high-speed data transmission, large power consumption, and high cost. Meanwhile, the serial links allows the transmitter to transmit data only with no synchronized clock information. For the purpose, clock and data recovery circuit becomes a very crucial key block. In this paper, a 5.4Gbps half-rate bang-bang CDR is designed for the applications of high-speed graphic DRAM interface. The CDR consists of a half-rate bang-bang phase detector, a current-mirror charge-pump, a 2nd-order loop filter, and a 4-stage differential ring-type VCO. The PD automatically retimes and demultiplexes the data, generating two 2.7Gb/s sequences. The proposed circuit is realized in 66㎚ CMOS process. With input pseudo-random bit sequences (PRBS) of $2^{13}-1$, the post-layout simulations show 10psRMS clock jitter and $40ps_{p-p}$ retimed data jitter characteristics, and also the power dissipation of 80mW from a single 1.8V supply.