• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3707-3710
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• 2010

A chromo/fluorogenic $NO_2S_2$-macrocycle L functionalized with nitrobenzofurazan unit as a dual-signaling probe was synthesized and structurally characterized by single crystal X-ray analysis. In a cation-induced color change experiment, L exhibited excellent $Hg^{2+}$ ion selectivity by showing the color change from orange-red to yellow. However, this hypochromic shift by $Hg^{2+}$ was observed for the weaker coordinating anion system such as ${NO_3}^-$ and ${ClO_4}^-$ ions. The observed anion effect is due to the strong coordination of anions inhibits the bond formation between $Hg^{2+}$ and the macrocyclic tert-N atom, which is sensitive to induce the color change. In the fluorometric experiment, L showed chelate-enhanced fluorescence change effect only with $Hg^{2+}$ ion, together with a change from yellow to green emission. The sensing ability for $Hg^{2+}$ with the proposed chemosensor L is due to the stable complexation with 1:1 stoichiometry (metal-to-ligand).

• YAKHAK HOEJI
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• v.22 no.2
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• pp.72-82
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• 1978

This study was undertaken establish the relationship between trypsin inhibitor in raw soybean and antinutritional effect of raw legumes. 1) Among legumes produced in Korea, Glycine max contains a relatively high amount of protein(higher than 40%) compared with kindey bean, sword bean and mung bean and, furthermore, soybean which contains a high amount of protein possesses high trypsin inhibitory activity. 2) Disc electrophoretic pattern exhibited pattern exhibited that the crude protein preparation from Glycine max produced about 9-12 protein bands, and the pattern of electrophoretic mobility was very similar to each other. However, only a few protein bands were observed from the crude protein preparation of yard long bean, sword bean, adzuki bean, mung bean and rice adzuki. From the eluate of the sliced gel, it was confirmed that among those bands, only the fastest moving band contains trypsin inhibitory activity. 3) In chicks fed the normal diet the body weight was increased steady from one week and reached to 40% increase for three weeks but in chick fed raw bean diet, there was no body weight gain until two weeks feeding and only 10-20% of body weight gain was observed at the end of three week feeding. On the other hand, in chicks fed raw bean diet the weight of pancreatic tissue per 100g body weight was increased to about two-fold for two or three weeks but there was no change in liver weight. 4) In the case of amylase secretion from the pancreatic fragment, very strong stimulation on amylase secretion from pancreatic tissue of chicks fed a normal diet was produced by one unit of cholecystokin-pancreozymin. However, no stimulation was observed from pancreatic fragment of chick fed raw bean diet.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.830-839
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• 2007

Pradimicins are potent antifungal antibiotics having an unusual dihydrobenzo[$\alpha$]naphthacenequinone aglycone substituted with D-alanine and sugars. Pradimicins are polyketide antibiotics produced by Actinomadura hibisca P157-2. The gene cluster involved in the biosynthesis of pradimicins was cloned and sequenced. The pradimicin gene cluster was localized to a 39-kb DNA segment and its involvement in the biosynthesis of pradimicin was proven by gene inactivation of prmA and prmB(ketosynthases $\alpha\;and\;\beta$). The pradimicin gene cluster consists of 28 open reading frames(ORFs), encoding a type II polyketide synthase(PKS), the enzymes involved in sugar biosynthesis and tailoring enzymes as well as two resistance proteins. The deduced proteins showed strong similarities to the previously validated gene clusters of angucyclic polyketides such as rubromycin, griseorhodin, and fredericamycin. From the pradimicin gene cluster, prmP3 encoding a component of the acetyl-CoA carboxylase complex was disrupted. The production levels of pradimicins of the resulting mutants decreased to 62% of the level produced by the wild-type strain, which indicate that the acetyl-CoA carboxylase gene would have a significant role in the production of pradimicins through supplying the extender unit precursor, malonyl-CoA.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.10
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• pp.1461-1466
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• 2014

GIS(Gas Insulated Switchgear) is important power apparatus which have strong dielectric strength, supply electric power and is a part of the power system. Most substation type is configured as GIS. Recently, because of continuous increasement of GIS demand resulted from high quality & big capacity of electric power, the necessity of the preventive & diagnosis system is being expanded gradually. GIS partial discharge occurred on the UHF band is detected effectively by the method to IEC 60270 that recommend to be able to detect the apparent minimum discharge, 5 pC. Additionally, the UHF sensor should be installed to detect PD signal if Partial discharge signal, 5 pC occur in every part of GIS. Currently PD diagnosis system applying UHF sensor for GIS with various voltage level like 154 kV, 345 kV, 765 kV have been operated. And it is necessary to measure and analyze insulation breakdown phenomenon of inside GIS exactly. In this paper, we proposed Fat-dipole patch UHF sensor that is developed and more sensitive, excellent wide-range characteristic than the exising UHF sensor. And we performed KERI (Korea Electrotechnology Research Institute) reference test, which showed the excellent result for the all tests.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.65-69
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• 2004

The small form factor optical data storage devices are developing rapidly nowadays. Since it is designed for portable and compatibility with flash memory, its components such as disk, head, focusing actuator, and spindle motor should be assembled within 5 m thickness. The thickness of focusing actuator is within 2 mm and the total working range is $+/-100{\mu}m$, with the resolution of less than $1{\mu}m$. Since the thickness is limited tightly, it is hard to place the yoke that closes the magnetic circuit and hard to make strong flux density without yoke. Therefore, Halbach array is adopted to increase the magnetic flux of one side without yoke. The proposed Halbach array type focusing actuator has the advantage of thin actuation structure with sacrificing less flux density than conventional magnetic array. The optical head unit is moved on the swing arm type tracking actuator. Focusing coil is attached to swing arm, and Halbach magnet array is positioned at the bottom of deck along the tracking line, and focusing actuator exerts force by the Fleming's left hand rule. The working range and resolution of focusing actuator are analyzed with FEM and experiment.

• Safety and Health at Work
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• v.12 no.4
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• pp.505-510
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• 2021

Background: Factors related to root causes can cause commonly occurring accidents such as falls, slips, and jammed injuries. An important means of reducing the frequency of occupational accidents in small- to medium-sized enterprises (SMSEs) of South Korea is to perform intensity analysis of the root cause factors for accident prevention in the cause and effect model like decision models, epidemiological models, system models, human factors models, LCU (life change unit) models, and the domino theory. Especially intensity analysis in a robot system and smart technology as Industry 4.0 is very important in order to minimize the occupational accidents and fatal accident because of the complexity of accident factors. Methods: We have developed the modern cause and effect model that includes factors of root cause through statistical testing to minimize commonly occurring accidents and fatal accidents in SMSEs of South Korea and systematically proposed educational policies for accident prevention. Results: As a result, the consciousness factors among factors of root cause such as unconsciousness, disregard, ignorance, recklessness, and misjudgment had strong relationships with occupational accidents in South Korean SMSEs. Conclusion: We conclude that the educational policies necessary for minimizing these consciousness factors include continuous training procedures followed by periodic hands-on experience, along with perceptual and cognitive education related to occupational health and safety.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.12
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• pp.31-38
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• 2021

This study contributes to the existing literature and tries to analyze the validity of the Fisher hypothesis in the Philippines. Using monthly data from January 1995 to December 2020, the empirical analysis used the Engle-Granger and Johansen cointegration testing technique. The correlation coefficient suggests a strong positive association. All things being equal, a rise in inflation leads to a rise in the nominal interest rate. The unit-root tests show that inflation and the nominal interest rate are both stationary. Based on both Engle-Granger and cointegrating regression Durbin-Watson tests, the nominal interest rate and inflation are cointegrated. Likewise, the results from Johansen cointegration indicate that there exists a long-run relationship between the variables. However, we rejected a one-to-one relationship between nominal interest rate and inflation. The error correction term coefficient (ECM) shows that it is statistically significant suggesting that the nominal interest rate adjusts to the inflation rate with a lag. The Pair-wise Granger Causality test reported a bi-directional causal relationship between nominal interest rate and inflation. Inflation targeting has been the monetary policy framework of choice for most central banks. In essence, the conclusions of this study are useful to central banks because they help them better comprehend the long-run equilibrium relationship between the nominal interest rate and inflation.

• Ocean and Polar Research
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• v.40 no.4
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• pp.271-280
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• 2018

The purpose of this study is to examine the causal relationship among oil consumption, oil-tanker accidents, and economic growth, and to derive policy implications from the results. Therefore, this paper attempts to analyze the short term, long term, and strong causality factors pertaining to the relationship between oil consumption, oil-tanker accidents, and economic growth in Korea using time-series techniques and annual data for the 1984-2016 period. Tests for unit roots, co-integration, and Granger-causality based on an error-correction model are presented. The results show that bidirectional causality exists between oil consumption and oil-tanker accidents, between economic growth and oil consumption, and between oil-tanker accidents and economic growth. The study shows that oil was used as a core energy source during the rapid economic growth of Korea in the past, and that this caused the number of oil-tanker accidents to rise as oil consumption increased.

• Journal of Korea Society of Digital Industry and Information Management
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• v.14 no.4
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• pp.17-26
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• 2018

Connected car plays an important role on Intelligent Transport System (ITS). ITS is able to secure drivers' convenience and safety, however, the overall system can be threatened by hacking attempt. Blockchain is one strong candidate of the remedy to promote the security of the ITS network. However, there will be many challenges to adopt previously proposed blockchain technologies to ITS. This work presents a new ITS structure based on blockchain technology. Proposed scheme includes three major layers. The first layer is central manager which is initiated once to register a certain connected car. The third layer is RSU (Road Side Unit) layer which exploits PoS (Proof of Stake) for consortium blockchains and retains real-time information. In addition, this layer performs block expiration based on timers to maintain manageable block length. In the second layer, the generated blocks of the third layer without expiration are housed as private blockchains. We finally demonstrate possible merits of newly proposed scheme.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.9
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• pp.1-9
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• 2021

This study aimed to investigate the existence of the Feldstein-Horioka (1980) puzzle in international macroeconomics by applying the conditional Autoregressive Distributed Lag (ARDL) model to examine the long-run relationship between national savings and investments in Thailand and China. The input of this study relied on annual national savings and investments as a fraction of GDP during 1980-2019 which was collected from China National Bureau of Statistics (NBS) and Thailand National Economic and Social Development Council (NESDC). Hypothetically, Augmented Dickey-Fuller (ADF) and Phillips-Perron (PP) unit root tests were applied to test the stationary properties and to investigate the integration level of selected time series. The empirical results, confirmed by cumulative sum (CUSUM) and cumulative sum square (CUSUMSQ), maintained no serial correlation and structural break problems. The finding of this study suggested that the Feldstein-Horioka puzzle in Thailand did not exist significantly. Thailand's national savings and investments nexus was independent, following the classic economic idea that financial liberalization, or perfect capital mobility, allowed national savings and investments to flow freely to countries with better interest rates. Whereas, a strong significant correlation was found in the case of China during the fixed exchange rate regime switching in 1994 and post WTO participation after 2001-2019.