• Journal of Navigation and Port Research
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• v.30 no.2
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• pp.161-166
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• 2006

In order to construct an Anechoic Chamber satisfying international standards for EMI testing, it has been recognized that the absorption characteristics of the EM wave absorber must be higher than 20 dB over the frequency band from 30 MHz to 18 GHz. In this paper, an EM wave absorber with super wide-band frequency characteristics was proposed and designed in order to satisfy the above requirements by using the Equivalent Material Constant Method(EMCM) and Finite Difference Time Domain(FDTD). The proposed absorber is to attach a pyramidal absorber onto a hemisphere-type absorber on a cutting cone-shaped ferrite. As a result, the proposed absorber has absorption characteristics higher than 20 dB over the frequency band from 30 MHz to more than 20 GHz.

• Journal of Technologic Dentistry
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• v.16 no.1
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• pp.5-11
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• 1994

On purpose of relative comparison of between air-vent attached pattern and non attached one, casting tests were accomplished by castability analysis unrig wax screen mesh pattern. Experimental specimens are divided Into 4groups. 1) Air-vent attached pattern with high casting pressure(coil spring type centrifugal casting machine 2.5turn). 2) Air-vent attached pattern with low casting pressure(coil spring type centrifugal casting machine 1.5turn). 3) Air vent non attached pattern with high casting pressure(coil spring type centrifugal casting machine 2.5turn). 4) Air-vent non attached pattern with low casting pressure(coil spring type centrifrgal casting machine 1.5turn). The main results are as follows : 1) The condition of high casting pressure no.1, no.3 were showed perfect castability. 2) The condition of low-casting pressure, there is a wide difference between no.2, no.4 group. Castability of no.2 group preferable to no.4 group(p<0.001). 3) Low casting pressure and complex shape cause the low-castability. So it is recommanded that use of air-vent in case of complex shaped wax pattern with low easting pressure.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.245-250
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• 2009

A variety of change in modern society has affected a family structure. In addition birth rate is getting lower and nuclear family type is getting common, influence of children has highly increased. According to this phenomenon, needs and concern about education and culture for children increase sharply. Children cultural complex can be learning field, which helps children not only to rediscover the world by themselves but also to have various and abundant experience. The purpose of this study is going to extract a planning factor of the children cultural complex through case studies of korean and oversea project for adaptable children cultural complex. In addition, this study tries to analyze the features of the children cultural complex in korean and oversea. Consequently, The analysis result is to be introduced party room to children cultural complex, used the PVC tile and carpet tile for safety of children and variety, and executed program relevant to nature.

• Bulletin of the Korean Mathematical Society
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• v.61 no.2
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• pp.557-584
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• 2024

An almost complex torus manifold is a 2n-dimensional compact connected almost complex manifold equipped with an effective action of a real n-dimensional torus Tⁿ ≃ (S¹)ⁿ that has fixed points. For an almost complex torus manifold, there is a labeled directed graph which contains information on weights at the fixed points and isotropy spheres. Let M be a 6-dimensional almost complex torus manifold with Euler number 6. We show that two types of graphs occur for M, and for each type of graph we construct such a manifold M, proving the existence. Using the graphs, we determine the Chern numbers and the Hirzebruch χ_y-genus of M.

• Genomics & Informatics
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• v.9 no.3
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• pp.114-120
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• 2011

Chronic inflammation has been implicated as one of the important etiological factors in insulin resistance and type 2 diabetes mellitus (T2DM). To investigate the role of anti-inflammatory cytokines in the development of T2DM, we conducted a case-control study to assess the association between IL4/IL4R polymorphisms and disease risk. We firstly identified single nucleotide poly-morphisms (SNP) at IL4 and IL4RA loci by sequencing the loci in Korean participants. Case-control studies were conducted by genotyping the SNPs in 474 T2DM cases and 470 non-diabetic controls recruited from community-based cohorts. Replication of the associated signals was performed in 1,216 cases and 1,352 controls. We assessed effect of IL4 -IL4RA interaction on T2DM using logistic regression method. The functional relevance of the SNP associated with disease risk was determined using a reporter expression assay. We identified a strong association between the IL4 promoter variant rs2243250 and T2DM risk (OR=0.77; 95% CI, 0.67~0.88; p=$1.65{\times}10^{－4}$ in the meta-analysis). The reporter gene expression assay demonstrated that the presence of rs2243250 might affect the gene expression level with ~1.5-fold allele difference. Our findings contribute to the identification of IL4 as a T2D susceptibility locus, further supporting the role of anti-inflammatory cytokines in T2DM disease development.

• Journal of the Korean Ceramic Society
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• v.45 no.5
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• pp.290-296
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• 2008

$AB'_{0.5}B"_{0.5}O_3$ type complex perovskite structures which have been reported as proton conductors over $600^{\circ}C$ were studied. The $AB'_{0.5}B"_{0.5}O_3$ type complex perovskite structure is known to be more easily synthesized and has better stability than normal $ABO_3$ perovskite structure. And it is stable at about $800^{\circ}C$ in the $CO_2$ atmosphere, whereas the $BaCeO_3$ perovskite is easily decomposed into carbonate. In addition, this $AB'_{0.5}B"_{0.5}O_3$ type complex perovskite structure could simply produce oxygen vacancies within their structure not by introducing additional doping oxides but by just controling the molar ratio of $B'^{+3}$ and $B"^{+5}$ metal ions in the B site. Hence it is easy to design the structure which shows highly sensitive electrical conductivity to humidity. In this study, the single phase boundary of $BaR_{0.5+x}Ta_{0.5-x}O_{3-{\delta}}$(R = rare earth) complex perovskite structures and it's phase stability were investigated with changes in composition, x. And the humidity dependance of electrical conductivity at different $P_{H2O}$ conditions was investigated.

• Annals of Clinical Neurophysiology
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• v.9 no.1
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• pp.36-38
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• 2007

The pathomechanisms involved in both restless legs syndrome (RLS) and complex regional pain syndrome type I (CRPS I) are still controversial whether they are central or peripheral origins. We recently encountered a patient who had an unusual coexistence of both RLS and CRPS I, and both of which showed good responses to sympathetic block. These findings suggest the role of peripheral mechanisms, especially unmyelinated small autonomic fiber, in both RLS and CRPS I.

• New Physics: Sae Mulli
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• v.68 no.11
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• pp.1225-1230
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• 2018

Schwinger pair production of electrons and positrons in a strong electric field is a prediction of nonperturbative quantum field theory, in which the out-vacuum is superposed of multi-particle states of the in-vacuum. Solving the Dirac or Klein-Gordon equation in the background field, though a linear wave equation, and finding the pair-production rate is a difficult or nontrivial job. The phase-integral method has recently been introduced to compute the pair production in space-dependent electric fields, and a complex analysis method has been employed to calculate the pair production in time-dependent electric fields. In this paper, we apply the complex analysis method to a Sauter-type electric field and other hyperbolic-type electric fields that vanish in the past and future and show that the Stokes phenomena in pair production occur when the time-dependent frequency for a given momentum has finite simple poles (polons) with pure imaginary residues.

• Annals of Clinical Neurophysiology
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• v.24 no.2
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• pp.35-45
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• 2022

Complex regional pain syndrome (CRPS) is a chronic regional pain disorder that most frequently affects the limbs. It is characterized by hyperalgesia, allodynia, edema, motor disturbance, and vasomotor instability, and typically occurs following surgery or trauma. In type-I CRPS there is no confirmed nerve injury, while peripheral nerve injury is present in type-II CRPS. The multifactorial pathophysiological etiology of CRPS includes inflammation, autoimmune responses, abnormal cytokine production, autonomic dysfunction, altered blood flow, psychological factors, and central cortical reorganization. There are no specific laboratory diagnostic tools for CRPS, and so it is diagnosed clinically. The Budapest criteria are currently the most-accepted diagnostic criteria.

• Molecules and Cells
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• v.28 no.4
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• pp.375-382
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• 2009

The 26S proteasome is a 2-MDa complex with a central role in protein turn over. The 26S proteasome is comprised of one 20S core particle and two 19S regulatory particles (RPs). The RPN12a protein, a non-ATPase subunit of the 19S RP, was previously shown to be involved in cytokinin signaling in Arabidopsis. To further investigate cellular roles of RPN12a, RNAi transgenic plants of RPN12a were constructed. As expected, the 35S:RNAi-RPN12a plants showed cytokinin signaling defective phenotypes, including abnormal formation of leaves and inflorescences. Furthermore, RNAi knock-down transgenic plants exhibited additional unique phenotypes, including concave and heart-shape cotyledons, triple cotyledons, irregular and clustered guard cells, and defects in phyllotaxy, all of which are typical for defective cytokinin signaling. We next examined the mRNA level of cytokinin signaling components, including type-A ARRs, type-B ARRs, and CRFs. The expression of type-A ARRs, encoding negative regulators of cytokinin signaling, was markedly reduced in 35S:RNAi-RPN12a transgenic plants relative to that in wild type plants, while type-B ARRs and CRFs were unaffected. Our results also indicate that in vivo stability of the ARR5 protein, a negative regulator of cytokinin signaling, is mediated by the 26S proteasome complex. These results suggest that RPN12a participates in feedback inhibitory mechanism of cytokinin signaling through modulation of the abundance of ARR5 protein in Arabidopsis.