• Journal of Korean Society of Environmental Engineers
• /
• v.31 no.9
• /
• pp.803-810
• /
• 2009

This study is conducted to examine spatial variations of Dissolved Organic Matter (DOM) in stream and waste waters of the different watershed areas (agricultural, residential, and industrial complex area) by using fluorescence 3D-EEMs (3 Dimensional Excitation Emission Matrix Spectroscopy). Furthermore, the research investigates the changes of DOM characterization by synchronous and 3D-EEMs during a rainfall event. The characterizations of DOM obtained by 3D-EEMs show two noticeable peaks at humic and protein-like regions. Humic-like substances (HLS) are found in rural and urban areas, and humic and protein-like substances (PLS) are shown in industrial area. According to the fluorescence peak $T_1:C_1$ ratios, it is observed that high amount of HLS was discharged from Banweol Industrial Complex (3TG). Additionally, linear relationships (Regression rate, $r^2$=0.65, $r^2$=0.66) have been shown between PLS (peak $T_1,\;B_1$) and biochemical oxygen demand (BOD), which indicates the impact of sewage. For the rainfall event (30 mm), no remarkable difference of DOM was found at rural area except increment of fluorescence intensity comparing dry period. In contrast, HLS at urban area is highly discharged within 30 minutes from the beginning of rainfall. Also, there are high influences of HLS and PLS within 20 minutes at industrial complex (4TG). Fluorescence 3D-EEMs has not only verifies a watershed of DOM origination but also monitors diffuse and point source impacts.

• Mass Spectrometry Letters
• /
• v.4 no.4
• /
• pp.59-66
• /
• 2013

A metabolomics study was conducted to identify urinary biomarkers for breast cancer, using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS), analyzed by principal components analysis (PCA) as well as a partial least squares-discriminant analysis (PLS-DA) for a metabolic pattern analysis. To find potential biomarkers, urine samples were collected from before- and after-mastectomy of breast cancer patients and healthy controls. Androgens, corticoids, estrogens, nucleosides, and polyols were quantitatively measured and urinary metabolic profiles were constructed through PCA and PLS-DA. The possible biomarkers were discriminated from quantified targeted metabolites with a metabolic pattern analysis and subsequent screening. We identified two biomarkers for breast cancer in urine, ${\beta}$-cortol and 5-methyl-2-deoxycytidine, which were categorized at significant levels in a student t-test (p-value < 0.05). The concentrations of these metabolites in breast cancer patients significantly increased relative to those of controls and patients after mastectomy. Biomarkers identified in this study were highly related to metabolites causing oxidative DNA damage in the endogenous metabolism. These biomarkers are not only useful for diagnostics and patient stratification but can be mapped on a biochemical chart to identify the corresponding enzyme for target identification via metabolomics.

• Journal of Korea Planning Association
• /
• v.54 no.3
• /
• pp.5-14
• /
• 2019

Starting with the market vitalization project in 2008, The Gwangju Dae-in Art Market has attracted to many artists, changing into cultural and art market. After the project was carried out for a certain period of time, a study was conducted to determine the differing opinions of the artists and merchants in regards to the market. The study also examined and analyzed the factors affecting the artists' continuous activities. The difference in recognition perception between artists and merchants was analyzed through a T-test. PLS-regression analysis was used for the artists' continuing intention to work. As a result, the artists and merchants recognized that the number of visitors increased after the influx of artists. Programs that had a positive impact on the artist's intention for sustainable activities were as follows: the 'Art Products Creation Workshop', where artists, merchants, and citizens collaborate to develop commodities needed for the market; 'Hanpyeong Gallery', where artists directly or indirectly interact with merchants and citizens; the 'Artist-Merchant Workshop', where artists and merchants produce articles required for the market; 'C'est Si Bon', which expresses the placeness of the market into art; and the 'Dae-in Art Night Market', where citizens, merchants and visitors can sell their own works. On the other hand, programs with the negative effect were those where artists' participation was low or none, as the policy implications, they should be actively develop this type of programs, where artists could participate and interact with citizens and merchants, like this visitors and sales can be increased.

• Journal of the Korean Vacuum Society
• /
• v.2 no.3
• /
• pp.275-281
• /
• 1993

본 논문은 포항가속기에서 건설 중인 진공 chamger의 용접에 관한 것이다. 저장링에 전자빔을 5시간 이상 저장하기 위하여 10-10torr 이하로 진공도를 유지하도록 설계되어 있기 때문에 초고진공에 적합한 TIG 용접(tungsten inert gas welding)을 하였다. 진공 chamber는 Al 5083-H321이며 flange의 재질은 Al 2219-T852이다. Sector chamber I, II의 총 용접 길이는 각각 27m, 37m이며 진공에 유해한 균열과 virtual leak가 생기지 않도록 하는 용접조건 등을 선정하였다.

• 순환기질환의공학회:학술대회논문집
• /
• 2001.11a
• /
• pp.39-40
• /
• 2001

• Asia pacific journal of information systems
• /
• v.28 no.4
• /
• pp.320-349
• /
• 2018

Purpose: The application of IoT is finding continuous acceptance in our daily lives, particularly, smart speakers are making life easier and convenient for consumers. This research aims to develop and test an integrated model of factors influencing consumer's adoption of voice-enabled IoT devices. Design/methodology/approach: Based on the VAM, an integrated voice-enabled IoT device adoption model is proposed. Gender differences on five constructs relating with perceived value (perceived usefulness, perceived enjoyment, perceived security risk, perceived technicality and perceived cost) was also examined through PLS-MGA technique. The usage experience of consumers was also controlled in the integrated VAM. Findings: Result shows that Perceived-Usefulness, Perceived-Enjoyment and Perceived-Cost have a strong effect on Perceived-Value. However, Perceived-Technicality and Perceived-Security-Risk are non-influential and have no significant effect on PV. Additionally, Perceived-Value and Social-Influence plays a significant role in predicting adoption intention. Gender differences also exist in consumers perception of usefulness, enjoyment and cost. In comparison to the basic value-based adoption model, the integrated model provides more insight on consumers adoption of voice-enabled IoT devices. Originality/value: Using an integrated model, this study is one of the first scholarly attempt at modelling the influential factors for adopting smart speakers i.e., voice-enabled IoT devices, with implications for improved adoption.

• Proceedings of the KIEE Conference
• /
• 1995.07c
• /
• pp.1365-1367
• /
• 1995

The PLS 2-GeV linac employs 11 units of high-power pulsed klystrons(80MW) as the main RF sources. The matching modulators of 200 MW(400kV, 500 A) can provide a flat-top pulse width of 4.4 ${\mu}s$ with a maximum pulse repetition rate of 120 Hz at the full power level. For a good stability of electron beams, the pulse-to-pulse flat-top voltage variation of a modulator requires less than 0.5%. In order to achieve this goal, we stabilized high voltage charging power supplies within 1% by a phase controlled SCR voltage regulator. In addition, we employed ac/dc feedback together with a resistive De-Q'ing system to achieve far less than 0.5% variation of the PFN charging voltage. This paper presents the main feature of the klystron-modulator system and the characteristics of the pulsed high-power RF system performance during the beam injection operation for the Pohang Light Source commissioning.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.4
• /
• pp.580-583
• /
• 2005

We have evaluated the application of spectroscopy using an insertion-type fiber-optic probe and a sensor at wavelengths from 400 to 1,100 nm to the measurement of milk fat content on dairy farms. The internal reflectance ratios of 183 milk samples were determined with a fiber-optic spectrophotometer at 5$^{\circ}C$, 20$^{\circ}C$ and 40$^{\circ}C$. Partial least squares (PLS) regression was used to develop calibration models for the milk fat. The best accuracy of determination was found for an equation that was obtained using smoothed internal reflectance data and three PLS factors at 20$^{\circ}C$. The correlation coefficients between predicted and reference milk fat at 5$^{\circ}C$, 20$^{\circ}C$ and 40$^{\circ}C$ were r=0.753, r=0.796 and r=0.783, respectively. The predictive explained variances ($Q^2$) of the final model, moreover, were more than 0.550 at all temperatures, and the regression coefficients of determination ($R^2$) were more than 0.6 (60%). Our results indicate that milk has different internal reflectance measured in the range of visible and near infrared wavelengths (400 to 1,100 nm), depending on its fat content.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.11
• /
• pp.75-81
• /
• 2020

This study aims to empirically test the effect of liquidity and adequacy on bank performance through interest rate risk and credit risk. Capital adequacy and liquidity are variables that can affect the ups and downs of opinion, where the bank's performance in this study is the dependent variable. Good credit distribution can minimize the occurrence of defaults. This study uses banking companies in Indonesia that are listed on the Indonesian stock exchange, with a total number of 43 banking companies, this study however, uses only 30 companies ranging from years 2014 to 2019, primarily due to the availability of the limited data. The data analysis techniques used in this study is PLS-SEM with the WarpPLS application. The research results show that capital adequacy and liquidity has a positive effect on bank performance, interest rate risk and credit risk can mediate capital adequacy on bank performance, interest rate risk can mediate liquidity on bank performance, and interest rate risk has a positive effect on bank performance. However, credit risk can't mediate liquidity on bank performance and credit risk does not have a positive effect on bank performance. This is in line with the commercial loan theory, shiftability theory and the doctrine of anticipated income, which explains how best to give credit, both in longer and the shorter term.

• The Journal of Information Systems
• /
• v.33 no.1
• /
• pp.159-182
• /
• 2024

Purpose This study aims to investigate the factors influencing social media users' sharing behaviors of COVID-19 health information. Specifically, we seek to examine the impact of three key antecedents-trust in information source, trust in information content, and trust in social media platform-on users' trust in information quality and determine whether their effects vary between South Korea and China. Design/methodology/approach To fulfill our research objectives, we conducted an online survey across two countries, collecting 408 valid responses (South Korea: N = 201; China: N = 207) for our analysis. We employed Partial Least Squared based Structural Equation Modeling (PLS-SEM) with SmartPLS 4 and performed Exploratory Factor Analysis (EFA) and independent t-tests with SPSS 27. Findings The study revealed that perceived risks significantly inhibit users from sharing health information, highlighting the critical role of trust in countering these effects. We also identified variances in the levels of trust in information content and trust in social media platform between the two countries, which offers fresh perspectives for designing culturally tailored public health communications and interventions.