• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.3
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• pp.563-569
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• 2007

As the mobile communication and the semiconductor technology is improved continuously, mobile contents such as the multimedia service and the 2D/3D graphics which require high level graphics are serviced recently. Mobile chips should consume small die area and low power. In this paper, we design a truncated floating-point multiplier that is useful for the 2D/3D vector graphics in mobile devices. The truncated multiplier is based on the radix-4 Booth's encoding algorithm and a truncation algorithm is used to achieve small area and low power. The average percent error of the multiplier is as small as 0.00003% and neglectable for mobile applications. The synthesis result using 0.35um CMOS cell library shows that the number of gates for the truncated multiplier is only 33.8 percent of the conventional radix-4 Booth's multiplier.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.585-588
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• 2014

This paper presents a self-powered sensor node circuit using photovoltaic and vibration energy harvesting. The harvested energy from a solar cell and a vibration device(PZT) is stored in a storage capacitor. The stored energy is managed by a PMU(Power Management Unit). In order to supply a stable voltage to the sensor node, an LDO(Low Drop Out Regulator) is used. The LDO drives a temperature sensor and a SAR ADC(Successive Approximate Register Analog-to-Digital Converter), and 10-bit digital output data corresponding to current temperature is obtained. The proposed circuit is designed in a 0.35um CMOS process, and the designed chip size including PADs is $1.1mm{\times}0.95mm$.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.43.1-43.1
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• 2020

Cassiopeia A (Cas A) is a young supernova remnant (SNR) where we observe the interaction of SNR blast wave with circumstellar medium. From the early optical studies, dense, slowly-moving, N-rich "quasi-stationary flocculi" (QSF) have been known. These are probably dense CNO-processed circumstellar knots that have been engulfed by the SNR blast wave. We have carried out near-infrared, high-resolution (R=45,000) spectroscopic observations of ~40 QSF, and here we present the result on a QSF knot (hereafter 'Knot 24') near the SNR boundary of Cas A. The average [Fe II] 1.644 um spectrum of Knot 24 has a remarkable shape with a narrow (~8 km/s) line superposed on the broad (~200 km/s) line emitted from shocked gas. The spatial morphology and the line parameters indicate that Knot 24 has been partially destroyed by a shock wave and that the narrow line is emitted from the unshocked material heated/ionized by the shock radiation. This is the first detection of the emission from the pristine circumstellar material of the Cas A supernova progenitor. We also detected H Br gamma and other [Fe II] lines corresponding to the narrow [Fe II] 1.644 um line. For the main clump where we can clearly identify the shock emission associated with the unshocked material, we analyze the observed line ratios using a shock model that includes radiative precursor. The analysis indicates that the majority of Fe in the unshocked material is in the gas phase, not depleted onto dust grains as in the general interstellar medium. We discuss the non-depletion of Fe in QSF and its implications on the immediate progenitor of the Cas A supernova.

• The Journal of the Acoustical Society of Korea
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• v.25 no.2
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• pp.61-71
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• 2006

An MP3 encoder chip has been designed and fabricated with the hardware and software co-design concepts. In the aspect of the software. the calculation cycles of the distortion control loop. which requires most of the calculation cycles in MP3 encoding procedure. have been reduced to $67\%$ of the original algorithm through the 'scale factor Pre-calculation'. By using a floating Point 32 bit DSP core and designing the FFT block with the hardware. we can get the additional reduction of the calculation cycles in addition to the software optimization. The designed chip has been verified using HW emulation and fabricated via 0.25um CMOS technology The fabricated chip has the size of $6.2{\time}6.2mm^2$ and operates normally on the test board in the qualitative and quantitative aspect.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.12
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• pp.53-60
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• 2005

This work proposes a 10b 100 MS/s $1.4\;mm^2$ CMOS ADC for low-power multimedia applications. The proposed two-step pipeline ADC minimizes chip area and power dissipation at the target resolution and sampling rate. The wide-band SHA employs a gate-bootstrapping circuit to handle both single-ended and differential inputs with 1.2 Vp-p at 10b accuracy while the second-stage flash ADC employs open-loop offset sampling techniques to achieve 6b resolution. A 3-D fully symmetrical layout reduces the capacitor and device mismatch of the first-stage MDAC. The low-noise references are integrated on chip with optional off-chip voltage references. The prototype 10b ADC implemented in a 0.18 um CMOS shows the maximum measured DNL and INL of 0.59 LSB and 0.77 LSB, respectively. The ADC demonstrates the SNDR of 54 dB, the SFDR of 62 dB, and the power dissipation of 56 mW at 100 MS/s.

• Journal of Applied Biological Chemistry
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• v.53 no.1
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• pp.44-50
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• 2010

Tae-Um-Jo-wee-Tang (TUJWT) and Do-Dam-Tang (DDT) have been used as an anti-obesity herbal medicine but their effect and mechanism of action have not been studied. We investigated the effects of TUJWT and DDT on energy and glucose homeostasis using Sprague Dawley female rats with diet-induced obesity. The mechanisms of action of TUJWT and DDT were studied whether they had anti-obesity effects. Rats fed a high-fat diet were divided into 3 groups: rats in each group received 2 g water extracts of modified TUJWT and DDT, or 2 g cellulose per kg body weight (a negative control) on a daily basis. A further group was fed a low-fat diet as a positive control. We found that DDT significantly decreased body weight and body fat (mesenteric fat and retroperitoneal fat) more than the control. This decrease was due to the reduction in energy intake but no changes of energy expenditure. However, DDT increased fat oxidation as a major energy source than the control. In addition, modified TUJWT and DDT improved glucose tolerance without changing serum insulin levels during an oral glucose tolerance test. In conclusion, DDT have a better anti-obesity effect than TUJWT by decreasing energy intake in female rats with diet-induced obesity. It also improves glucose tolerance.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.3
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• pp.253-263
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• 2020

Reactive oxygen species (ROS) plays an important role in maintaining homeostasis. However, excessive ROS production damages cellular components such as proteins, lipids, and nucleic acids and promotes skin aging. In this study, we confirmed the antioxidant effect of CSYJE to prevent excessive oxidative stress. First, DPPH and ABTS assays were performed to confirm the antioxidant effect of CSYJE and the radical scavenging activity was confirmed depending on the concentration. As a result of performing the MTT assay to confirm the cell viability, it was confirmed that there was no cytotoxicity at a concentration of 1,000 ㎍/mL. As a result of western blotting to confirm the expression levels of the antioxidant-related proteins nuclear-E2-related factor 2 (Nrf2) and Heme oxygenase-1 (HO-1), it was confirmed that the expression was increased in a concentration-dependent manner. After inducing ROS with lipopolysaccharide (LPS), an intracellular ROS-causing substance, DCF-DA was performed to confirm the inhibitory effect of ROS production, and the inhibition of ROS production was confirmed to concentration-dependent. Real-time RT-PCR was performed to confirm the mRNA expression level of inflammatory cytokines and inflammatory mediator caused by ROS generation, mRNA expression was reduced in a dose dependent manner. Therefore, this study confirmed the antioxidant effect of CSYJE through the Nrf2/HO-1 signaling pathway, which suggests that CSYJE can be used as an antioxidant cosmetic material by inhibiting free radicals.

• Journal of the Microelectronics and Packaging Society
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• v.12 no.2 s.35
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• pp.105-109
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• 2005

A compact antenna switch module for GSM/DCS dual band applications based on multilayer low temperature co-fired ceramic (LTCC) substrate is presented. Its size is $4.5{\times}3.2{\times}0.8 mm^3$ and insertion loss is lower than 1.0 dB at Rx mode and 1.2 dB at Tx mode. To verify the stability of the developed module to the process window, each block that is diplexer, LPF's and bias circuit is measured by probing method in the variation with the thickness of ceramic layer and the correlation between each block is quantified by calculating the VSWR In the mean while, two types of bias circuits -lumped and distributed - are compared. The measurement of each block and the calculation of VSWR give good information on the behavior of full module. The reaction of diplexer to the thickness is similar to those of LPF's and bias circuit, which means good relative matching and low value of VSWR, so total insertion loss is maintained in quite wide range of the thickness of ceramic layer at both band. And lumped type bias circuit has smaller insertion itself and better correspondence with other circuit than distributed stripline structure. Evaluated ceramic module adopting lumped type bias circuit has low insertion loss and wider stability region of thickness over than 6um and this can be suitable for the mass production. Stability characterization by probing method can be applied widely to the development of ceramic modules with embedded passives in them.

• Journal of the Korean earth science society
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• v.42 no.5
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• pp.504-513
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• 2021

Different physical processes, according to the atmospheric boundary layer types, were used in the Local Data Assimilation and Prediction System (LDAPS) of the Unified Model (UM) used by the Korea Meteorological Administration (KMA). Therefore, it is important to verify the atmospheric boundary layer types in the numerical model to improve the accuracy of the models performance. In this study, the atmospheric boundary layer types were verified using observational data. To classify the atmospheric boundary layer types, summer intensive observation data from radiosonde, flux observation instruments, Doppler wind Light Detection and Ranging(LIDAR) and ceilometer were used. A total number of 201 observation data points were analyzed over the course 61 days from June 18 to August 17, 2019. The most frequent types of differences between LDAPS and observed data were type 1 in LDAPS and type 2 in observed(each 53 times). And type 3 difference was observed in LDAPS and type 5 and 6 were observed 24 and 15 times, respectively. It was because of the simulation performance of the Cloud Physics such as that associated with the simulation of decoupled stratocumulus and cumulus cloud. Therefore, to improve the numerical model, cloud physics aspects should be considered in the atmospheric boundary layer type classification.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.18 no.2
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• pp.86-92
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• 2005

Painful ophthalmoplegia due to idiopathic granulomatous inflammation of the cavernous sinus/superior orbital fissure has been termed Tolosa-Hunt syndrome(THS). The syndrome is characterized by pain behind, above or around the eye, involvement of the cranial nerves which pass through the cavernous sinus, spontaneous remissions and exacerbations, and a favourable response to steroid therapy. There was the 56 years old man who suffered from painful ophthalmoplegia and facial palsy. The oriental medical treatment without steroids and analgesics reduced the symptoms of the patient remarkably during 5 weeks. There is few report that treat THS with oriental medical method. If more clinical trials like this are proved to be effective, we can expect that oriental medical treatment will be a good method in THS.