• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.306-311
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• 2016

Li-air batteries have received much attention due to their superior theoretical energy density. However, their sluggish kinetics on the cathode side is considered the main barrier to high performance. The rational design of electrode catalysts with high activity is therefore an important challenge. To solve this issue, we performed density functional theory (DFT) calculations to analyze the adsorption behavior of the $LiO_2$ molecule, which is considered to be a key intermediate in both the Li-oxygen reduction reaction (ORR) and the evolution reaction (OER). Specifically, to use the activity descriptor approach, the $LiO_2$ adsorption energy, which has previously been demonstrated to be a reliable descriptor of the cathode reaction in Li-air batteries, was calculated on $LaB_{1-x}B^{\prime}_xO_3$(001) (B, B' = Mn, Fe, Co, and Ni, x = 0.0, 0.5). Our fast screening results showed that $LaMnO_3$, $LaMn_{0.5}Fe_{0.5}O_3$, or $LaFeO_3$ would be good candidate catalysts. We believe that our results will provide a way to more efficiently develop new cathode materials for Li-air batteries.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.4
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• pp.571-579
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• 2016

In this work, we prepared a panel of monoclonal anti-idiotypic antibodies to ovine prolactin (oPRL) by the hybridoma technique. Among these antibodies, one anti-idotypic antibody (designated B7) was chosen for further characterization by a series of experiments. We first demonstrated that B7 behaved as a typical $Ab2{\beta}$ based on a series of enzyme-linked immunosorbent assays. Subsequently, the results of a competitive receptor-binding assay confirmed that B7 could specifically bind to the prolactin receptor (PRLR) expressed on target cells. Finally, we examined its biological activities in CHO-PRLR and Nb2 cells and observed that B7 could activate Janus kinase 2-signal transducer and activator of transcription signalling in CHO-PRLR and Nb2 cells and induce BaF3 proliferation. The present study suggests that i) B7 can serve as a PRLR agonist or PRL mimic and has potential applications in regulating mammary gland development, milk production and maintenance of lactation in domestic animals and ii) B7 may be a biological reagent that can be used to explore the mechanism of PRLR-mediated intracellular signalling.

• Journal of applied mathematics & informatics
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• v.11 no.1_2
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• pp.155-164
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• 2003

The existence and representations of some generalized inverses, including ${A_{T,*}}^{(2)},\;{A_{T,*}}^{(1,2)},\;{A_{T,*}}^{(2,3)},\;{A_{*,S}}^{(2)},\;{A_{*,S}}^{(1,2)}\;and\;{A_{*,S}}^{(2,4)}$, are showed. As applications, the perturbation theory for the generalized inverse {A_{T,S}}^{(2)} and the perturbation bound for unique solution of the general restricted system $A_{x}$ = b(dim(AT)=dimT, $b{\in}AT$ and $x{\in}T$) are studied. Moreover, a characterization and representation of the generalized inverse ${A_{T,*}}^{(2)}$ is obtained.

• JSTS:Journal of Semiconductor Technology and Science
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• v.4 no.4
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• pp.300-306
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• 2004

This paper reports a novel tunable bandpass filter using two-state switched inductor with direct-contact MEMS switches for wireless LAN applications. In our filter configuration, the switched inductor is implemented to obtain more stable and much larger frequency tuning ratio compared with variable capacitor-based tunable filter. The proposed tunable filter was fabricated using a micromachining technology and electrical performances of the fabricated filter were measured. The filter consists of spiral inductors, MIM capacitors and direct-contact type MEMS switches, and its frequency tunability is achieved by changing the inductance that is induced by ON/OFF actuations of the MEMS switches. The actuation voltage of the MEMS switches was measured of 58 V, and they showed the insertion loss of 0.1 dB and isolation of 26.3 dB at 2 GHz, respectively. The measured center frequencies of the fabricated filter were 2.55 GHz and 5.1 GHz, respectively. The passband insertion loss and 3-dB bandwidth were 4.2 dB and 22.5 % at 2.55 GHz, and 5.2 dB and 23.5 % at 5.1 GHz, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.11 s.102
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• pp.1106-1113
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• 2005

This paper presents a dual-band mixer for multi-standards of IEEE 802.1la/b/g using a single local oscillator, so as to improve the defects of legacy systems. Those systems have duplicate local oscillators and mixers to handle dual band signals, increasing complexity of system and power loss. The proposed circuit shows 11.6 dB, 16.8 dB of conversion loss and 8.77 dBm, 12.5 dBm of IIP3(Input 3rd Intercept Point) for respective bands when the two RF inputs of 2.452 and 5.260 GHz are down-converted to the identical 356 MHz If frequency. The RF-LO isolations are measured 36 dB, 41 dB at each frequencies and over 50 dB of LO-IF isolations are achieved at all cases.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.5
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• pp.53-61
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• 2002

In this paper, we will introduce a design of key recovery based on XML can be used in B2B environment. XML Digital Signature and XML Encryption that are defied recently as standards by W3C(World Wide Web Consortium) are deployed to sign/verify or encrypt/decrypt documents for electronic commerce and keys to store/load at/from key recovery server. The result of signature or encryption is always an XML document and all messages used in this key recovery system are also XML documents. It enables to adapt transparently this key recovery system to legacy XML applications and electronic commerce platforms based on XML. And its method for key recovery is key escrow. One of the characteristics of this key recovery is that one enterprise can recover keys of some documents for electronic commerce from external key recovery system in other enterprises related with them and also recover keys from owns.

• Advanced Industrial SCIence
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• v.3 no.2
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• pp.31-37
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• 2024

This paper presents a single and 2-patch microstrip array antenna operated on a frequency of 10.3GHz(x-band). It outlines the process of designing a microstrip patch array antenna using CST MWS. Initially, a single microstrip antenna was designed, followed by optimization using CST MWS to attain optimal return losses and gain. Subsequently, the design was expanded to create a 2×1 microstrip inset-fed array antenna for the X-band applications. The construction material is Roger RO4350B, with specific dimensions (h=0.79mm, 𝜖_r = 3.54). The achieved results include an S11 of -18dB at the resonant frequency (10.3GHz), a gain of 9.82dBi, a bandwidth of 0.165GHz, and a 3-dB beamwidth of 30°, 121° in Az(𝜑=0) and El(𝜑=90) plane, respectively. The future plan involves the fabrication of this array antenna and further expansion to a 4×4 array of microstrip antennas. It is then incorporated on the X-band applications for practical uses.

• ETRI Journal
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• v.24 no.3
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• pp.190-196
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• 2002

This paper presents millimeter wave monolithic microwave integrated circuit (MMIC) low noise amplifiers using a $0.15{\mu}m$ commercial pHEMT process. After carefully investigating design considerations for millimeter-wave applications, with emphasis on the active device model and electomagnetic (EM) simulation, we designed two single-ended low noise amplifiers, one for Q-band and one for V-band. The Q-band two stage amplifier showed an average noise figure of 2.2 dB with an 18.3 dB average gain at 44 GHz. The V-band two stage amplifier showed an average noise figure of 2.9 dB with a 14.7 dB average gain at 65 GHz. Our design technique and model demonstrates good agreement between measured and predicted results. Compared with the published data, this work also presents state-of-the-art performance in terms of the gain and noise figure.

• Archives of Pharmacal Research
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• v.27 no.7
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• pp.776-780
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• 2004

Interferons are cytokines that confer resistance to viral infection and inhibit cellular proliferation. The interferon alpha gene from human blood samples was amplified, cloned and expressed in E. coli (BL21). Leukocyte chromosomal DNA was used as a source of template DNA. Using specific primers, the gene for HulFN$\{alpha}$-2b was amplified and inserted into the E. coli vector, pET21b, by ligation of the HindIII and BamHI linkers of the vector and insert. The insert was further analyzed by PCR, DNA restriction mapping and sequencing, and expressed in a suitable E. coli strain. The production of this important cellular protein in the laboratory has significant applications in production of the recombinant pharmaceutical proteins.

• International Journal of Reliability and Applications
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• v.11 no.2
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• pp.107-122
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• 2010

This paper deals with the reliability analysis of a complex system, which consists of two subsystems A and B connected in series. Subsystem A has only one unit and B has two units $B_1$ and $B_2$. Marked process has been applied to model the complex system. Present reliability model incorporated two repairmen: supervisor and novice to repair the failed units. Supervisor is always there and the novice remains in vacation and is called for repair as per demand. The repair rates for supervisor and novice follow general and exponential distributions respectively and the failure time for both the subsystems follows exponential distribution. The model is analyzed under "Head of line repair discipline". By employing supplementary variable technique, Laplace transformation and Gumbel-Hougaard family of copula various transition state probabilities, reliability, availability and cost analysis have been obtained along with the steady state behaviour of the system. At the end some special cases of the system have been taken.