• Geomechanics and Engineering
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• 제18권1호
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• pp.71-83
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• 2019

This investigation presented conventional triaxial and creep-permeability tests on sandstones considering thermally-induced damage (TID). The TID had no visible effects on rock surface color, effective porosity and permeability below $300^{\circ}C$ TID level. The permeability enlarged approximately two orders of magnitude as TID increased to $1000^{\circ}C$ level. TID of $700^{\circ}C$ level was a threshold where the influence of TID on the normalized mass and volume of the specimen can be divided into two linear phases. Moreover, no prominent variations in the deformation moduli and peak strength and strain appeared as TID< $500^{\circ}C$ level. It is interesting that the peak strength increased by 24.3% at $700^{\circ}C$ level but decreased by 11.5% at $1000^{\circ}C$ level. The time-related deformation and steady-state creep rate had positive correlations with creep loading and the TID level, whereas the instantaneous modulus showed the opposite. The strain rates under creep failure stresses raised 1-4 orders of magnitude than those at low-stress levels. The permeability was not only dependent on the TID level but also dependent on creep deformation. The TID resulted in large deformation and complexity of failure pattern for the sandstone.

• 한국자기공명학회논문지
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• 제16권1호
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• pp.22-33
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• 2012

Tid1, belonging to the Hsp40/DnaJ family of proteins, functions as a cochaperone of cytosolic and mitochondrial Hsp70 proteins. In particular, the N-terminal J-domain of Tid1 (Tid1-JD) constitutes the major binding sites for proteinprotein interactions with client proteins, including p53, as well as its partner chaperone, Hsp70. In the present study, soluble, recombinant protein of Tid1-JD could be obtained by using the pCold vector system, and backbone NMR assignments were completed using the isotope $[^{13}C/^{15}N]$-enriched protein. Far-UV CD result implied that Tid1-JD is an ${\alpha}$-helical protein and the secondary structure determined using chemical shift data sets indentified four ${\alpha}$-helices with a loop region containing the HPD (conserved tripeptide of His, Pro and Asp) motif. Additionally, NMR spectra under different conditions implied that the HPD motif, which is a critical region for protein-protein interactions of Tid1-JD, would possess dynamic properties.

• BMB Reports
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• 제55권10호
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• pp.488-493
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• 2022

The specific pair of heat shock protein 70 (Hsp70) and Hsp40 constitutes an essential molecular chaperone system involved in numerous cellular processes, including the proper folding/refolding and transport of proteins. Hsp40 family members are characterized by the presence of a conserved J-domain (JD) that functions as a co-chaperone of Hsp70. Tumorous imaginal disc 1 (Tid1) is a tumor suppressor protein belonging to the DNAJA3 subfamily of Hsp40 and functions as a co-chaperone of the mitochondrial Hsp70, mortalin. In this work, we performed nuclear magnetic resonance spectroscopy to determine the solution structure of JD and its interaction with the glycine/phenylalanine-rich region (GF-motif) of human Tid1. Notably, Tid1-JD, whose conformation was consistent with that of the DNAJB1 JD, appeared to stably interact with its subsequent GF-motif region. Collectively with our sequence analysis, the present results demonstrate that the functional and regulatory mode of Tid1 resembles that of the DNAJB1 subfamily members rather than DNAJA1 or DNAJA2 subfamily proteins. Therefore, it is suggested that an allosteric interaction between mortalin and Tid1 is involved in the mitochondrial Hsp70/Hsp40 chaperone system.

• 한국자기공명학회논문지
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• 제22권3호
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• pp.64-70
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• 2018

Human Tid1, belonging to the family of the Hsp40/DnaJ, functions as a co-chaperone of cytosolic and mitochondrial Hsp70 proteins. In addition, the conserved J-domain and G/F-rich region of Tid1 has been suggested to interact with the p53 tumor suppressor protein, to translocate it to the mitochondria. Here, backbone NMR assignments were achieved for the putative p53-binding domain of Tid1. The obtained chemical shift information identified five ${\alpha}$-helices including four helices characteristic of J-domain, which are connected to a short ${\alpha}$-helix in the G/F-rich region via a flexible loop region. We expect that this structural information would contribute to our progressing studies to elucidate atomic structure and molecular interaction of the domain with p53.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 통신소사이어티 추계학술대회논문집
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• pp.212-215
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• 2003

본 논문에서는 IEEE 802.11e MAC (Medium Access Control) 프로토콜을 NS-2 등과 같은 유명한 시뮬레이터들보다도 진보적인 NCTUns 시뮬레이터를 이용하여 개발하고자 하면서, 각 MSDU (MAC Service Data Unit)마다 제공되어야 하는 TID (Traffic Identification) 를 결정하는 방안을 모색하고 있다. 따라서 본론에서는 IEEE 802.l1e MAC 프로토콜과 NCTUns 시뮬레이터 에 대해서 기술하며 본 논문에서 제안하는 방법에 대해서 서술한다.

• 한국항공우주학회지
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• 제41권1호
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• pp.79-84
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• 2013

DC/DC 컨버터는 임의의 직류전원을 부하가 요구하는 형태의 직류전원으로 변환시키는 효율이 높은 전력변환기이다. DC/DC 컨버터는 PWM-IC(펄스폭 변조 집적회로) 제어기, MOSFET(산화물-반도체 전계 효과 트랜지스터), 인덕터, 콘덴서 등으로 구성되어있다. 코발트 60 ($^{60}Co$) 저준위 감마발생기를 이용한 TID실험에서 방사선의 영향으로 PWM-IC의 전기적 특성중에 문턱전압과 옵셋전압이 증가되고, SEL에 적용된 4종류의 중이온 입자는 PWM-IC의 파형을 불안정하게 만든다. 또한, 입/출력관계의 파형을 SPICE 시뮬레이션 프로그램으로 관찰하였다. PWM-IC의 TID 실험은 30 Krad 까지 수행하였으며, SEL 실험을 제어보드를 구현한 후 LET($MeV/mg/cm^2$)별 cross section($cm^2$)으로 연구하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권9호
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• pp.1326-1333
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• 2002

Studies were conducted with nine barrows, average initial body weight $44.5{\pm}2.1kg$, fitted with a T-cannula at the distal ileum, to determine the apparent ileal (and true) digestibility (AID and TID) of CP and AA in different cultivars of rapeseed meals and soybean meal. The barrows were fed either a casein diet or one of eight corn starch-based semipurified diets, formulated to contain 17.0% CP (DM basis) with one of seven different cultivars of rapeseed meal or soybean meal as the sole source of dietary protein, according to a six-period, nine-treatment, incomplete Latin Square. Chromic oxide (0.5%) was used as a digestibility marker. The pigs were fed of 4% of body weight twice daily, at 08:00 and 20:00 h. Ileal digesta were collected at 2 h intervals daily from 5 d to 7 d. The AID or TID values of CP and most AA (Cysteine excluded) were significantly lower in the rapeseed meals than in soybean meal (p<0.05). There were significant differences in the AID or TID values of CP and AA among the seven different cultivars rapeseed meals (p<0.05); the seven rapeseed meals were arranged according to the size of the AA digestibility values of the rapeseed meals from the greatest to the least, as Zayou 59, Youyan 7, Ganyou 16, Qingyou 2, Huaza 3, Ningza 1 and Lianglou 586; differences in CP, AA, NDF and ADF contents in the rapeseed meals were mainly responsible for the variation in the AID or TID values of AA among rapeseed meals. The AID value of CP can be used as an index of the AID or TID values of most AA in rapeseed meals. However, the AID value of CP was less appropriate as a direct indicator of the AID or TID values for cysteine, methionine, tryptophan, phenylalanine and proline.

• Nuclear Engineering and Technology
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• 제42권4호
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• pp.394-413
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• 2010

The object of this paper is to identify the key elements that impact a radiation dose at EAB (Exclusion Area Boundary). This study is based on the AST (Alternative Source Terms) as defined in Regulatory Guide 1.183. The LOCA (Loss of Coolant Accident) and the LRA (Locked Rotor Accident) are selected as limiting cases. A sensitivity analysis of accidental behavior with respect to various parameters during LOCA and LRA at Kori Unit 1 is also undertaken for the following objectives: to determine the limiting parameters, to find the impact trend of the radiation dose, and to find the safety margin between AST and TID (Technical Information Document) methodologies. This work confirms that key parameters are particulate removal rate, decontamination factor, iodine chemical form, gap fraction, partitioning factor, and the impact of isotopes group. Comparing TID with AST, the radiation dose of TID is about 80% greater than that of AST under a LOCA, and about 60% greater than that of AST for the case of a LRA; thus the safety margin is remarkably increased when the AST is used. In this work, the sensitivity analysis results are presented in terms of a sensitivity index called the "NDD (Normalized Dose Difference)", which compares the impact of parameters with that of a reference case. These values are derived by using a combination of the leak rate (primary to secondary), iodine chemical form, gap fraction, partitioning factor, spray removal rate, source term, and other variables.

• 항공우주기술
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• 제7권1호
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• pp.68-75
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• 2008

우주방사선환경은 위성의 운용궤도와 임무 기간 및 시기에 따라 달라지고 시뮬레이션을 통 해 예측이 가능하다. 총 이온화 조사량(TID)의 경우 dose-depth 곡선으로 차폐두께에 따른 조사량을 알 수 있다. 그러나 이는 차폐두께에 따른 조사량의 정보만 보여주므로 실제 차폐 구조물의 형상에 따른 부품수준에서의 총 이온화 조사량을 예측하기 위해서는 구조물의 형태를 고려한 유효 방사선 차폐두께의 상세 분석이 필요하다. 이를 위해 다양한 구조형상을 3차원 좌표로 입력하여 모델링이 가능하게 하고 여기에 임의 지점에서 방사되는 ray를 이용하여 구조체의 전 방향에 대한 유효 차폐두께분포를 계산하는 프로그램을 개발하였다. 이 분포결과를 위성의 우주임무환경에서 예측되는 dose-depth 곡선 데이터와 결합하여 최종적으로 위성내부의 임의지점에서 예측되는 총 이온화 조사량을 계산함으로써 3차원 구조형상을 고려한 상세 분석이 가능하도록 하였다. 이를 이용하여 위성의 전자박스구조를 모델링하여 부품수준의 임의지점에서 예측되는 총 이온화 조사량을 분석하였다.

• Nuclear Engineering and Technology
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• 제56권2호
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• pp.568-574
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• 2024

The development of radiation-tolerant radio-frequency (RF) systems can be a solution for applications in extreme radiation environments, such as nuclear power plant monitoring and space exploration. Among the crucial components within an RF system, the low noise amplifier (LNA) stands out due to its vulnerability to TID effects, mainly relying on transistors as its main devices. In this study, the TID effects in the LNA using standard 0.18 ㎛ complementary metal oxide semiconductors (CMOS) technology are estimated and analyzed. The results show that the LNA can withstand absorbed radiation up to 100 kGy. The S₂₁, S₁₁, noise figure (NF), stability (K), and linearity of the third input intercept point (IIP3) slightly shifted from the initial values of 0.8312 dB, 0.793 dB, 0.00381 dB, 1.34406, and 2.36066 dBm, respectively which are still comparable to the typical performances. Moreover, the standard 0.18 ㎛ technology has demonstrated its radiation tolerance, as it exhibits negligible performance degradation in the conventional LNA even when exposed to radiation levels up to 100 kGy. In this context, simulation approach offers a means to predict the TID effects and estimate the radiation exposure limit for electronic devices, particularly when transistors are used as the primary RF components.