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A Study of Micro, High-Performance Solenoid-Type RF Chip Inductor (Solenoid 형태의 소형.고성능 RF Chip 인덕터에 대한 연구)

  • Kim, Jae-Uk;Yun, Ui-Jung;Jeong, Yeong-Chang;Hong, Cheol-Ho;Seo, Won-Chang
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.49 no.5
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    • pp.283-288
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    • 2000
  • In this work, small-size, high-performance simple solenoid-type RF chip inductors utilizing an Al2O3 core material were investigated. Copper (Cu) wire with $40\mum$ diameter was used as the coils and the size of the chip inductor fabricated in this work was $2.1mm\times1.5mm\times1.0mm$. The external current source was applied after bonding Cu coil leads to gold pads electro-plated on each end of backsides of a core material. High frequency characteristics of the inductance (L), quality factor (Q), and impedance (Z) of developed inductors were measured using an RF Impedance/Material Analyzer (HP4291B with HP16193A test fixture). This HP4291B was also used to obtain the equivalent circuit and its circuit parameters of the chip inductors. This HP4291B was also used to obtain the equivalent circuit and its circuit parameters of the chip inductors. The developed inductors have the self-resonant frequency (SRF) of 1.1 to 3.1 GHz and exhibit L of 22 to 150 nH. The L of the inductors decreases with increasing the SRF. The Z of the inductors has the maximum value at the SRF and the inductors have the quality factor of 70 to 97 in the frequency range of 500 MHz to 1.5 GHz.

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Effects of Dietary Energy Density on Growth, Carcass Quality and mRNA Expression of Fatty Acid Synthase and Hormone-sensitive Lipase in Finishing Pigs

  • Liu, Z.H.;Yang, F.Y.;Kong, L.J.;Lai, C.H.;Piao, X.S.;Gu, Y.H.;Ou, X.Q.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.10
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    • pp.1587-1593
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    • 2007
  • A single factorial experiment was conducted to test the effects of three dietary levels of energy on mRNA expression of fatty acid synthase (FAS-mRNA) and hormone-sensitive lipase (HSL-mRNA) and their association with intramuscular fat in finishing pigs. 72 crossbred (Large $White{\times}Rongchang$) barrows with an average initial body weight of 20.71 (s.e. 0.1) kg, were randomly allotted to three dietary treatments (11.75, 13.05 and 14.36 MJ DE/kg) and fed until slaughtered at 100 or 101 kg. The diets were iso-nitrogenous and iso-essential amino acids. The growth performances including the duration of finishing were changed linearly (p<0.05) or quadratically (p<0.05) with increased dietary energy levels. The effects of dietary energy content on the percentage of external fat, intramuscular backfat and the fat thickness were linear (p<0.05). The content of dietary energy increased FAS-mRNA linearly or quadratically, while HSL-mRNA decreased linearly or quadratically in backfat and Longissmus dorsi muscle. Meanwhile, significant positive correlations (p<0.05) were found between energy level and intramuscular fat, FAS-mRNA or the ratio of FAS-mRNA to HSL-mRNA, between the ratio of FAS-mRNA to HSL-mRNA and intramuscular fat. However, the correlations between HSL mRNA and dietary energy or intramuscular fat were negative (p<0.05). The results indicated that dietary energy level regulates lipid accumulation, especially intramuscular fat, possibly by modulating the mRNA of FAS and HSL together rather than individually.

Effects of Immune Stress on Performance Parameters, Intestinal Enzyme Activity and mRNA Expression of Intestinal Transporters in Broiler Chickens

  • Feng, Y.;Yang, X.J.;Wang, Y.B.;Li, W.L.;Liu, Y.;Yin, R.Q.;Yao, J.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.5
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    • pp.701-707
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    • 2012
  • Immune stress is the loss of immune homeostasis caused by external forces. The purpose of this experiment was to investigate the effects of immune stress on the growth performance, small intestinal enzymes and peristalsis rate, and mRNA expression of nutrient transporters in broiler chickens. Four hundred and thirty-two 1-d-old broilers (Cobb500) were randomly assigned to four groups for treatment; each group included nine cages with 12 birds per cage. Group 1 = no vaccine (NV); Group 2 = conventional vaccine (CV); group 3 = lipopolysaccharide (LPS)+conventional vaccine (LPS); group 4 = cyclophosphamide (CYP)+conventional vaccine (CYP). The results demonstrated that immune stress by LPS and CYP reduced body weight gain (BWG), feed intake (FI), small intestine peristalsis rate and sIgA content in small intestinal digesta (p<0.05). However, the feed conversion ratio (FCR) remained unchanged during the feeding period. LPS and CYP increased intestinal enzyme activity, relative expression of SGLT-1, CaBP-D28k and L-FABP mRNAs (p<0.05). LPS and CYP injection had a negative effect on the growth performance of healthy broiler chickens. The present study demonstrated that NV and CV could improve growth performance while enzyme activity in small intestine and relative expression of nutrient transporter mRNA of NV and CV were decreased in the conditions of a controlled rational feeding environment. It is generally recommended that broilers only need to be vaccinated for the diseases to which they might be exposed.

Design and Fabrication of Filter Banks for Implementation of Cavity Tunable Filter (캐비티 가변필터의 구현을 위한 필터뱅크 설계 및 제작)

  • Shin, Yeonho;Kang, Sanggee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.6
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    • pp.169-173
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    • 2014
  • In order to satisfy user's requirements of needs for various services and to efficiently use of frequency, a communication system using one platform can support many communication services. Tunable filters must be used in the front end of broadband communication systems which provide and support various communication methods. In this paper we design and implement a filter bank to verify the feasibility of cavity tunable filter with the operation frequency of 800 MHz ~ 1600 MHz. The filter bank is composed of five bandpass filters and each bandpass filter has the same operation frequency band of the tunable filter. The implemented filter bank has the maximum insertion loss of 0.326 dB, the bandwidth of 37 MHz ~ 84 MHz, and the attenuation of minimum 19.974dB and mximum 37.812dB at the band edge ${\pm}60MHz$ over the operating frequency band.

Preparation and Characterization of Nafion Composite Membranes Containing 1-ethyl-3-methylimidazolium Tetracyanoborate

  • Shin, Mun-Sik;Park, Jin-Soo
    • Journal of the Korean Electrochemical Society
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    • v.15 no.1
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    • pp.35-40
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    • 2012
  • The composite membranes using Nafion as matrix and 1-ethyl-3-methylimidazolium tetracyanoborate (EMITCB) as ion-conducting medium in replacement of water were prepared and characterized. The amount of EMITCB in Nafion varied from 30 to 50wt%. The composite membranes are characterized by ion conductivity, thermogravitational analyses (TGA) and small-angle X-ray scattering (SAXS). The composite membranes containing EMITCB of 40wt% showed the maximum ionic conductivity which was ~0.0146 S $cm^{-1}$ at 423.15 K. It is inferred that the decrease in ionic conductivity of all the composite membranes might be due to the decomposition of a tetracyanoboric acid formed in the composite membranes. The results of SAXS indicated that the ionic clusters to conduct proton in the composite membranes were successfully formed. In accordance with the results of ionic conductivity as a function of a reciprocal temperature, SAXS showed a proportional decrease in scattering maximum $q_{max}$ as the amount of EMITCB increases in the composite membranes, which results in the increase in ionomer cluster size. The TGA showed no significant decomposition of the ionic liquid as well as the composite membranes in the range of operating temperature ($120-150^{\circ}C$) of high temperature proton exchange membrane fuel cells (HTPEMFC). As a result, EMITCB is able to play an important role in transferring proton in the composite membranes at elevated temperatures with no external humidification for proton exchange membrane fuel cells.

A Study on the Coupling Performance Improvement of Cylindrical DR Bandpass Filter using Travelling Wave Mode Analysis (진행모드 해석을 이용한 유전체 공진기 대역통과 필터의 결합 특성 개선에 관한 연구)

  • Lee, Won-Hui;Park, Chang-Won;Yang, Jae-Hyuck;Hur, Jung;Lee, J. H.;Lee, Sang-Young
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2000.11a
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    • pp.125-129
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    • 2000
  • In this paper, We designed and fabricated C-band bandpass filter using dielectric resonators. From waveguide cutoff frequency which applied the region between adjacent dielectric resonators, the height of cavity is determined. The cavity's diameter is determined to the twice of dielectric resonator's diameter considering the conductor loss. The resonant frequency of the DR-cavity is calculated with travelling wave mode analysis. Conventionally, circular cylindrical dielectric resonator is analysed by Cohn's model which use the evanescent mode in the region between dielectric resonator wall and circular cavity wall, which is an approximated method. The external quality factor, Q$_{ex}$ has found with simulation result using Ansoft's Maxwell simulation tool. The designed filter using dielectric resonators with dielectric constant of 45 has the passband center at 5.065GHz. The bandpass filter using dielectric resonators have about 1dB insertion loss. 20MHz bandwidth and more than 30dB attenuation at f$_{0}$$\pm$15MHz.z.z.

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Computational Drug Discovery Approach Based on Nuclear Factor-κB Pathway Dynamics

  • Nam, Ky-Youb;Oh, Won-Seok;Kim, Chul;Song, Mi-Young;Joung, Jong-Young;Kim, Sun-Young;Park, Jae-Seong;Gang, Sin-Moon;Cho, Young-Uk;No, Kyoung-Tai
    • Bulletin of the Korean Chemical Society
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    • v.32 no.12
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    • pp.4397-4402
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    • 2011
  • The NF-${\kappa}B$ system of transcription factors plays a crucial role in inflammatory diseases, making it an important drug target. We combined quantitative structure activity relationships for predicting the activity of new compounds and quantitative dynamic models for the NF-${\kappa}B$ network with intracellular concentration models. GFA-MLR QSAR analysis was employed to determine the optimal QSAR equation. To validate the predictability of the $IKK{\beta}$ QSAR model for an external set of inhibitors, a set of ordinary differential equations and mass action kinetics were used for modeling the NF-${\kappa}B$ dynamic system. The reaction parameters were obtained from previously reported research. In the IKKb QSAR model, good cross-validated $q^2$ (0.782) and conventional $r^2$ (0.808) values demonstrated the correlation between the descriptors and each of their activities and reliably predicted the $IKK{\beta}$ activities. Using a developed simulation model of the NF-${\kappa}B$ signaling pathway, we demonstrated differences in $I{\kappa}B$ mRNA expression between normal and different inhibitory states. When the inhibition efficiency increased, inhibitor 1 (PS-1145) led to long-term oscillations. The combined computational modeling and NF-${\kappa}B$ dynamic simulations can be used to understand the inhibition mechanisms and thereby result in the design of mechanism-based inhibitors.

The Design of High-Temperature Superconducting Microstrip Filter Using Multiple Coupled Line Resonators (다중 결합 선로 공진기를 이용한 고온초전도 마이크로스트립 여파기의 설계)

  • Park, Hee-Chan;Yun, Seok-Sun;Park, Ik-Mo;Kim, Tae-Il;Kim, Sang-Kyoon;Min, Byoung-Chul;Jang, Jeong-Pil;Lee, Haeng-Seon;Choi, Young-Hwan;Oh, Byung-Du
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.38 no.5
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    • pp.23-31
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    • 2001
  • A very compact narrowband high-temperature superconducting microstrip filter using multiple coupled line resonators is designed and fabricated to effectively use the limited space of the wafer. The fabricated 12 pole filter has a center frequency of 1.79 GHz and a 3dB bandwidth of 7.63 MHz(0.43% fractional bandwidth). The filter also shows sharp skirt characteristics of 71 dB/MHz and 41dB/MHz blow and above the passband, respectively, and has an insertion loss of less than 0.5dB and a return loss of more than 15dB in the passband.

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Congenital muscular dystrophy type 1A with residual merosin expression

  • Kim, Hyo Jeong;Choi, Young-Chul;Park, Hyung Jun;Lee, Young-Mock;Kim, Heung Dong;Lee, Joon Soo;Kang, Hoon-Chul
    • Clinical and Experimental Pediatrics
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    • v.57 no.3
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    • pp.149-152
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    • 2014
  • Congenital muscular dystrophy type 1A (MDC1A) is an autosomal recessive disorder characterized by hypotonia, elevated serum creatine kinase level, delayed motor milestones, white matter changes observed by brain magnetic resonance imaging, and normal intelligence. A mutation in the laminin ${\alpha}2$ (LAMA2) gene, located at 6q22-23, is a genetic cause of MDC1A. Patients have merosin (laminin ${\alpha}2$)-deficient skeletal muscles. However, the degree of merosin expression ranges from total absence to partial reduction. Patients with residual merosin expression have more variable and milder phenotypes than those with absolute merosin deficiency. We observed a Korean girl with MDC1A with residual merosin expression. Clinical presentation of this patient was typical except for late onset of the disease and external capsule involvement. Immunohistochemical staining of muscle fibers including merosin, is important to evaluate patients with hypotonia, delayed motor development, and abnormal white matter changes.

The influence of the genu varum and the genu valgum on malalignment of the lower limb (내반슬, 외반슬의 부정정렬이 하지에 미치는 영향)

  • Moon, Sung-Gi
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.6 no.2
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    • pp.31-38
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    • 2000
  • The influence of the genu varum and the genu valgum in two groups of twenty adult man with deformation on hip joint, knee joint, ankle joint is as follows. 1. Each and all, the statistics that measure tibiofemorial angle indicated the group of the genu varum 168 1.42 and the group of the genu valgum 193 2.21, that was more larger or smaller than normal angle 183 of tibiofemorial. The measure Q-Angle(patellofemorial) indicates the group of the genu varum 9 1.5, the genu valgum 19 2.3, that was larger or smaller than normal angle 13. 2. It showed that range of motion hip joint adduction in the group of the genu varum was more larger than normal range of motion hip joint abduction in the group of the genu valgum was more larger than normal range of motion, hip joint internal rotation in the group of the genu valgum was more larger than normal range of motion, hip joint external rotation in the group of the genu varum was more larger than normal range of motion. 3. range of motion knee joint flexion was simillar to two groups of the genu varum and the genu valgum. On tibial tortion of the leg, the group of the genu varum indicated medial tibial tortion, and the genu valgum indicated lateral tibial tortion. 4. Each groups of the genu varum and the genu valgum in plantarflexion and dorsiflexion of ankle joint. With peak angle, the group of the genu varum showed toe-in that was more smaller than normal angle, and the group of the genu valgum showed toe-out that was more larger than normal angle.

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