• Korean Journal of Soil Science and Fertilizer
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• v.32 no.4
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• pp.440-445
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• 1999

In order to investigate the change of physiological active compounds in buckwheat with soil chemical properties and soil conditioners, we cultured buckwheat at an experimental open field station, Chonnam Provincial Agicultual Reserch and Extension Service. Fatty acids, phenolic compounds and tyrosinase inhibitory activity (TIA) from buckwheat grains and plants were analyzed. The contents of fatty acids in buckwheat plants was less than that of buckwheat grain. The fatty acids of buckwheat plants and grains were composed of saturated and unsaturated fatty acids. The contents of unsaturated fatty acids were more than saturated fatty acids. The phenolic compounds in buckwheat were from $682.6mg\;kg^{-1}$ to $1822mg\;kg^{-1}$. The phenolic compounds in buckwheat with addition of applied lime were $1822mg\;kg^{-1}$. It was higher than any other plot. The tyrosinase inhibitory activity (TIA) of sediment c in buckwheat grain with addition of applied lime was 92.8%. It was more than that of sediment a, b or compound A, B, C within the same treatment. But the TIA of compound C in buckwheat with application of borax was 81.0%. It was highest of all sediments and compounds within the same treatment.

• Journal of Chest Surgery
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• v.55 no.6
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• pp.462-469
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• 2022

Background: Carotid endarterectomy (CEA) is used to treat carotid stenosis, which is associated with cerebral infarction and may result in neurologic deficits such as stroke, transient ischemic attack (TIA), and local nerve injury. To decrease surgery-related complications and improve patient satisfaction with esthetic outcomes, efforts have been made to minimize incision size instead of using a standard longitudinal incision. Methods: We performed a retrospective analysis of 151 cases of CEA, of which 110 used conventional incisions and 41 used high mini-skin incisions (HMIs), from March 2015 to December 2021 at a single institution. Short-term (30-day) postoperative results were evaluated for rates of mortality, stroke, TIA, and cranial/cervical nerve injuries. Risk factors for nerve injury were also assessed. Results: The HMI group showed significantly (p<0.01) shorter operative and clamp times than the conventional group. The HMI group also had significantly shorter incision lengths (5.3±0.9 cm) than the conventional group (11.5±2.8 cm). The rates of stroke, TIA, and death at 30 days were not significantly different between the 2 groups. There was no significant difference in the rate of cranial and cervical nerve injuries, and all injuries were transient. A high lesion level (odds ratio [OR], 9.56; 95% confidence interval [CI], 3.21-28.42; p<0.01) and the clamp time (OR, 1.07; 95% CI, 1.03-1.12; p<0.01) were found to be risk factors for nerve injuries. Conclusion: Use of the HMI in CEA for carotid stenosis was advantageous for its shorter operative time, shorter internal carotid artery clamp time, reduced neurologic complications, and improved esthetics.

• Korean Journal of Optics and Photonics
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• v.24 no.1
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• pp.1-8
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• 2013

In this paper, we report design, fabrication and characterization of the WBRM (Wide Band Receiver Module) for LADAR (LAser Detection And Ranging) application. The WBRM has been designed and fabricated using self-made APD (Avalanche Photodiode) and TIA (Trans-impedance Amplifier). The APD and TIA chips have been integrated on 12-pin TO8 header using self-made ceramic submount and circuit. The WBRM module showed 450 ps of rise time, and corresponding 780 MHz bandwidth. Furthermore, it showed very low output noise less than 0.8 mV, and higher SNR than 15 for 150 nW of MDS(Minimum Detectable Signal). To the author's knowledge, this is the best performance of an optical receiver module for LIDAR fabricated by 200 um InGaAs APD.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.9
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• pp.31-39
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• 2011

In this paper, we propose a signal readout system with small area and low power consumption for CNT sensor arrays. The proposed system consists of signal readout circuitry, a digital controller, and UART I/O. The key components of the signal readout circuitry are 64 transimpedance amplifiers (TIA) and SAR-ADC with 11-bit resolution. The TIA adopts an active input current mirror (AICM) for voltage biasing and current amplification of a sensor. The proposed architecture can reduce area and power without sampling rate degradation because the 64 TIAs share a variable gain amplifier (VGA) which needs large area and high power due to resistive feedback. In addition, the SAR-ADC is designed for low power with modified algorithm where the operation of the lower bits can be skipped according to an input voltage level. The operation of ADC is controlled by a digital controller based on UART protocol. The data of ADC can be monitored on a computer terminal. The signal readout circuitry was designed with 0.13${\mu}m$ CMOS technology. It occupies the area of 0.173 $mm^2$ and consumes 77.06${\mu}W$ at the conversion rate of 640 samples/s. According to measurement, the linearity error is under 5.3% in the input sensing current range of 10nA - 10${\mu}A$. The UART I/O and the digital controller were designed with 0.18${\mu}m$ CMOS technology and their area is 0.251 $mm^2$.

• Korean Journal of Construction Engineering and Management
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• v.16 no.3
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• pp.165-176
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• 2015

Recently many Korean large-sized construction companies as well as specialty contractors have been expanding their business in the overseas market to mitigate impacts from long-term stagnation in the domestic market. Such as a result, it has been arisen as a major issue that contractors effectively manage the delays which have been commonly faced with in international mega-projects. Therefore it can be said that the ability of the delays management leads a success of project. This paper presents a review of literature for delay analysis methods such as time impact analysis(TIA) and raises practical problems to rationally substantiate the duration of extension of time(EoT) in international mega projects which have wide scope of works as well as complicated and detailed contract baseline programs by taking theoretical approaches. We suggest the two improvement concepts to substantiate the EoT claims which are effectively applicable to practical projects. The first is to sort out dominant delays among numerous delays in advance of applying a delay analysis. The second is to set up the delay sections with the advanced concept for analysing delays' effects by TIA. This study performed a case study on an actual international mega-project. to confirm the effectiveness of improvement concepts that this practical approach is applicable for the assessment of EoT. In conclusion, this paper supposes to provide practitioner in charge for an EoT claim with an advanced substantiation methodogy when they not only analyse the construction delays by using TIA, but also negotiate with stakeholders about with the assessment of EoT.

• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.48-53
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• 2017

Since the number and the amount of toxic substances handled by domestic companies have been increased, the possibility of serious chemical accidents has become severe. According to Chemistry Safety Clearing-house (CSC), the number of chemical accidents for the last five years has been rapidly raised. A representative example which shows the serious impact of a chemical accident is HF (Hydrogen Fluoride) accident generated in Gumi in 2012. In order to make effective responses for mitigating losses of accidents, the most suitable consequence model has to be selected and implemented throughout the considerations of chemical properties and environments. Even if each consequence model has been verified by the results of experiments, it is necessary to analyze and compare the usability of them according to various scenarios. In this study, the Gumi HF accident is simulated by HGSYSTEM, which is the most specialized model for the release and dispersion of HF. It is found that the ending point of ERPG-2 is about 1 km from the accident point. In order to investigate the usability of the most representative consequence models (ALOHA and CARIS), the results of them are compared with one of HGSYSTEM.

• Food Engineering Progress
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• v.21 no.3
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• pp.292-298
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• 2017

The aim of this study was to evaluate the effects of microencapsulation on the water absorption, DPPH radical scavenging activity (DRSA), hydroxyl radical scavenging activity (HRSA) and tyrosinase inhibition activity (TIA) in corn silk extracts. The lowest value (0.20) of water absorption index (WAI) and the highest value (95.23%) of water solubility index (WSI) were maltodextrin+cyclodextrin microencapulated corn silk extracts (MD+CD) and cyclodextrin encapulated corn silk extracts (CD), respectively. The 18.60% for DRSA value of control was increased to 89.25% for that of CD. The 16.89% for HRSA value of control was increased to 47.46%, and 7.16% for TIA value of control was increased to 39.35% for that of MD+CD, respectively. The MD+CD would be used for functional food and cosmetics materials as antioxidant and skin whitening agents. All investigated responses between control and treatment were statistically significant (p<0.05).

• 대한핵의학회:학술대회논문집
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• 1989.06a
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• pp.119.2-119.2
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• 1989

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.7 s.349
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• pp.13-19
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• 2006

A 5Gb/s cross coupled transimpedance amplifier (TIA) & limiting amp(LA), regulated cascode(RGC) is realized in a 0.18$\mu$m CMOS technology for optical printed circuit board applications. The optical receiver demonstrates $92.8db{\Omega}$ transimpedance and limiting amplifier gain, 5Gb/s bandwidth for 0.5pF photodiode capacitance, and 9.74mW power dissipation from 1.8V, 2.4V supply. Input stage impedance is $50{\Omega}$. The circuit was implemented on an optical PCB, and the 5Gb/s data output signal was measured with a good data eye opening.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.4C
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• pp.380-387
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• 2002

In this paper, the effect of the phase noise of a local oscillator on the ACPR of a transmitter and the reception sensitivity of a receiver to meet the TIA/EIA/IS-98-D for the CDMA mobile station was analyzed. And the optimum condition for performance of the local oscillator was suggested. It was found that the phase noise level of the local oscillator in a receiver and a transmitter should be below -138.3dBc/Hz and -120dBc/Hz, respectively, at 900kHz offset. It was confirmed that the reception sensitivity and ACPR efficiency were satisfactory when the signal of the local oscillator to the down-converter of a receiver with the phase noise level of less than -138.3dBc/Hz is supplied to the up-converter of the transmitter.