Value Information of Free Cash Flow : In View of Agency Cost of Free Cash Flow Hypothesis

Jangwoo Lee,Hee-Young Hurr 한국재무학회 2008 한국재무학회 학술대회 Vol.2008 No.11

We try to test a value information effect of free cash flow by using related variables alone or in composition. Our study will be a contribution in that it adds to the understanding of the market response to dividend payout and capital expenditures - especially when these financial activities are related with free cash flow. Also, our study chooses an analytic approach which is differentiated from extant literatures mainly depending on event studies. Our test result shows that more free cash flow are linked to lower firm value spread. Corporate activities that diminish free cash flow - for example capital expenditures, dividend payout, use of debt - are linked to higher market value. More growth options are confirmed to be associated with more firm value spread. The interaction terms also exhibit consistency. Asian financial crisis in late 1997 brought about test results somewhat different from pre-crisis periods.

Technology Acquisition Strategies in the Korean Computer Industry : A Micro Perspective

Lee, Jangwoo 경북대학교 경제경영연구소 1989 經商論集 Vol.17 No.2

With the computer industry as the case in point, this paper examines how local firms in Korea acquired technological capabilities which enabled them to enter new technology industries and sustain phenomenal growth in the international market. Investigating technological behaviors of 44 local firms in the Koran computer industry, it identifies different patterns of technological strategy associated with four types of firms, which is categorized by two variables : the production capablility and innovation capability at the time of entry into the industry. Statistical analyses suggest that technology acquisition strategies are distinctly different among four types of firms.

Association of urinary phthalate metabolites and phenolics with adipokines and insulin resistance related markers among women of reproductive age

Lee, Inae,Kim, Sunmi,Park, Suhyeon,Mok, Sori,Jeong, Yunsun,Moon, Hyo-Bang,Lee, Jangwoo,Kim, Sungkyoon,Kim, Hai-Joong,Choi, Gyuyeon,Choi, Sooran,Kim, Su Young,Lee, Aram,Park, Jeongim,Choi, Kyungho Elsevier BV 2019 Science of the Total Environment Vol.688 No.-

<P><B>Abstract</B></P> <P>Chemicals such as phthalates and phenolics have been associated with metabolic markers in humans. However, most studies have only looked at a limited number of chemicals, and little is known about their potential effects on adipokines in humans. In the present study, the associations between dozens of urinary chemicals, including phthalate metabolites and phenolics, and markers related to insulin resistance as well as major adipokines, were assessed among the women of reproductive age (<I>n</I> = 459, between 20 and 48 years of age) recruited from major cities in Korea between 2015 and 2016. Adipokines such as adiponectin and leptin, and insulin resistance related markers such as glucose and insulin, were analyzed in serum. Associations between urinary chemicals and the adipokines or insulin resistance related markers were assessed in two steps. First, ordinary least squares (OLS) regression was used to assess the association of each urinary chemical with the adipokines or insulin resistance related markers (single-pollutant model). Second, several chemicals were selected using elastic net regression and were subsequently analyzed with OLS regression model (multi-pollutant model), considering simultaneous exposure to multiple chemicals. In both single- and multi-pollutant models, several urinary chemicals consistently showed significant associations with adipokines or the insulin resistance related markers. The sum of di-(2-ethylhexyl) phthalate metabolites (ΣDEHPm) and ethyl paraben (EtP) were associated with increased serum adiponectin levels. Urinary ΣDEHPm levels also showed positive associations with fasting glucose. Moreover, urinary mono-methyl phthalate (MMP), mono-isobutyl phthalate (MiBP), and bisphenol S (BPS) levels showed positive associations with the homeostasis model assessment for insulin resistance (HOMA-IR). Interestingly, urinary propyl paraben (PrP) levels showed a negative association with HOMA-IR, in both models. Our observations show that among many consumer chemicals, phthalates may affect serum adipokines, and thus glucose, and insulin resistance in adult females. Further confirmation is warranted in other populations.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Urinary chemicals and metabolism related markers were measured in women of reproductive age. </LI> <LI> Multiple chemicals were considered in statistical models for adipokines and insulin resistance. </LI> <LI> Sum of DEHP metabolites and EtP were positively associated with serum adiponectin levels. </LI> <LI> Sum of DEHP metabolites was significantly associated with increased fasting glucose. </LI> <LI> MiBP was significantly associated with for increased HOMA-IR. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Bisphenol A distribution in serum, urine, placenta, breast milk, and umbilical cord serum in a birth panel of mother–neonate pairs

Lee, Jangwoo,Choi, Kyungho,Park, Jeongim,Moon, Hyo-Bang,Choi, Gyuyeon,Lee, Jeong Jae,Suh, Eunsook,Kim, Hai-Joong,Eun, So-Hee,Kim, Gun-Ha,Cho, Geum Joon,Kim, Sung Koo,Kim, Sungjoo,Kim, Su Young,Kim, Se Elsevier 2018 Science of the Total Environment Vol.626 No.-

<P><B>Abstract</B></P> <P>Bisphenol A (BPA) exposure during the perinatal and postnatal periods increases the susceptibility to disease over the life cycle. However, information on the BPA delivered to fetuses or infants via the placenta and breastfeeding is limited. We determined the BPA exposure levels in various bodily fluids and tissues of pregnant women and described fetus and infant exposures to BPA based on associations and BPA ratios in mother–neonate paired samples. Maternal serum, urine, placenta, breast milk, cord serum, and neonatal urine samples were collected from 318 mother–neonate pairs at six university hospitals in Korea. BPA levels were detected using liquid chromatography tandem mass spectrometry. The ratios of the BPA levels in the other sample types to the levels in maternal serum were calculated. BPA was detected in 79.5–100% of the maternal and fetal samples. The median BPA concentration in the samples decreased in the order of neonatal urine (4.75ng/mL), maternal urine (2.86ng/mL), cord serum (1.71ng/mL), maternal serum (1.56ng/mL), breast milk (0.74ng/mL), and the placenta (0.53ng/g). We estimated the ratios of BPA levels in the other sample types to those in maternal serum. The median (95th percentile) cord serum-to-maternal serum ratio was 1.12 (15.2) for 160 mother–fetal pairs, in which BPA was detected in both samples. The placenta-, maternal urine-, neonatal urine-, and breast milk-to-maternal serum ratios were 0.28 (5.31), 1.79 (29.9), 1.98 (28.2), and 0.51 (10.5), respectively. In addition, the median (95th percentile) cord serum-to-placenta ratio was 4.03 (45.8), and the neonatal urine-to-cord serum ratio was 1.95 (25.6). The 95th percentile values were 14–20-fold greater than the medians. Urine contained the highest BPA concentrations, followed by serum, breast milk, and the placenta. The variations of BPA ratio show individual differences in the amounts of BPA delivered from mother to fetus.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Not enough data on tissue distribution of BPA in mother‑neonate (or fetus) pair </LI> <LI> The order of BPA concentrations in examined tissue or bio-samples are urine in mother and neonates>cord serum>maternal serum>breast milk>placenta. </LI> <LI> BPA in cord serum, significantly associated with in maternal serum and urine but not in others. </LI> <LI> The variations of BPA ratio show individual differences in the amounts of BPA delivered from mother to fetus. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Optimizing Ganoderma lucidum Mycelial Production Using Swine Wastewater as a Substrate

Jangwoo LEE,Jinmo AHN,Gyuseong HAN,Joonyeob LEE,Taewoan KOO,Seokhwan HWANG 한국생물공학회 2014 한국생물공학회 학술대회 Vol.2014 No.10

Quantitative and qualitative changes in antibiotic resistance genes after passing through treatment processes in municipal wastewater treatment plants

Lee, Jangwoo,Jeon, Jong Hun,Shin, Jingyeong,Jang, Hyun Min,Kim, Sungpyo,Song, Myoung Seok,Kim, Young Mo Elsevier 2017 The Science of the total environment Vol.605 No.-

<P><B>Abstract</B></P> <P>In this study, quantitative and qualitative changes in antibiotics resistance genes (ARGs) were investigated in two municipal wastewater treatment plants (WWTPs) treating pretreated livestock or industrial wastewater as well as municipal sewage. Total eight ARGs (<I>tet</I>X, <I>tet</I>M, <I>tet</I>A, <I>sul</I>1, <I>sul</I>2, <I>erm</I>B, <I>qnr</I>D, and <I>bla</I> <SUB>TEM</SUB>) were quantified, and their relative abundance was assessed by ARGs copies/16S rRNA gene copies. The fate of ARGs was observed to be different between two WWTPs: <I>sul</I>, <I>qnr</I>D, and <I>bla</I> <SUB>TEM</SUB> were proliferated during the treatment processes only in the WWTP1 which received pretreated livestock wastewater. Furthermore, dynamic shifts in patterns of ARGs occurrence were observed during biological, secondary sedimentation and coagulation processes. During biological treatment in both WWTPs, relative abundance of <I>tet</I> and <I>erm</I>B changed: <I>tet</I> increased significantly by 211.6–357.6%, while <I>erm</I>B decreased by 70.4–92.0%. Little variation was observed in <I>sul</I>, <I>qnr</I>D and <I>bla</I> <SUB>TEM</SUB>. Subsequently, the relative abundance of <I>tet</I> decreased during the secondary sedimentation and coagulation in both WWTPs: <I>tet</I> decreased by 56.0–86.3% during sedimentation and by 48.2–75.7% during coagulation, respectively. During the final treatment, different responses of antibiotic resistance bacteria (ARB) and ARGs to ultraviolet (UV) disinfection were found: removal efficiencies of ARB were observed in the range of 34–75%, while obvious reduction in ARGs was not observed at the UV dose of 27mJ/cm<SUP>2</SUP>. Although ARGs underwent various treatment processes, considerable levels of ARGs remained at discharge amounting to 4.2×10<SUP>18</SUP> copies/day from WWTP1 and 5.4×10<SUP>16</SUP> copies/day from WWTP2, respectively.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Quantitative and qualitative changes in ARGs were investigated in WWTPs. </LI> <LI> Changes were unique for each ARG community while undergoing treatment processes. </LI> <LI> Variation in ARGs was largest during biological and post-physiochemical processes. </LI> <LI> ARGs showed limited response to UV disinfection. </LI> <LI> ARB were reduced by UV disinfection. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

DEHP, DEP and DBP Exposure Analysis using Urinary Metabolites of Gyonggi Province University Students

Lee, JangWoo,Kho, YoungLim,Kim, SungKyoon,Choi, Kyungho,Hwang, SeongHee,Jeong, Jeeyeon,Kim, Pangyi Korean Society of Environmental Health 2013 한국환경보건학회지 Vol.39 No.5

Objectives: Phthalates are used as plasticizers in polyvinyl chloride (PVC) plastics. As phthalate plasticizers are not chemically bound to the PVC, they can leach, migrate or evaporate into indoor air and atmosphere, foodstuffs, other materials, etc. Therefore, humans are exposed through ingestion, inhalation, and dermal exposure over their entire lifetime, including during intrauterine development. In particular, university students have a great number of opportunities to contact products including phthalates during campus life (food packaging, body care products, cosmetic, lotions, aftershave, perfume etc.). The purpose of this study was to examine levels of phthalate exposure as undergraduate students begin to use pharmaceuticals and personal care products including phthalates. Methods: Phthalate metabolites, mono-ethyl phthalate (MEP), mono-n-butyl phthalate (MnBP), mono-isobutyl phthalate (MiBP), mono-2- ethylhexyl phthalate (MEHP), {(mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP}, and mono-(2-ethlyl-5-oxohexyl) phthalate (MEOHP} were examined. 80 urine samples collected from university students were analyzed using LC/MS/MS(API 4000, Applied Bioscience) with on-line enrichment and columnswitching techniques. This study was carried out at Y university located in Gyonggi Province from 2008 to 2011. Results: The detection limit of phthalate metabolites were 0.03 ng/mL for MEP, 0.11 ng/mL for MnBP, 0.08 ng/mL for MiBP, 0.93 ng/mL for MEHP, 0.19 ng/mL for MEOHP and 0.16ng/mL for MEHHP. MnBP showed the highest urinary levels (median: 31.6 ug/L, 24.8 ug/g creatinine (cr)). Concentrations were also high for MEHHP (median: 24.1 ug/L, 19.0 ug/g cr), followed by MEOHP (median: 22.8 ug/L, 17.9 ug/g cr). In individual cases, the maximum level reached up to 348 ug/L, and 291 ug/g cr, respectively. The urinary and creatinine adjusted levels of MEP were lower than those for DBP and DEHP metabolites, but were higher in 95th percentiles. As a result, the mean daily DEP intake value was 2.3 ${\mu}g/kg$ bw/day, 3.5 ${\mu}g/kg$ bw/day for DEHP and 4.9 ${\mu}g/kg$ bw/day for DBP. Conclusion: These students' phthalate exposure levels were below the international safe level set by the EU, but higher than the 2012 KFDA survey of the age group from 3 to 18.

An 8-b 1GS/s Fractional Folding CMOS Analog-to-Digital Converter with an Arithmetic Digital Encoding Technique

Lee, Seongjoo,Lee, Jangwoo,Lee, Mun-Kyo,Nah, Sun-Phil,Song, Minkyu The Institute of Electronics and Information Engin 2013 Journal of semiconductor technology and science Vol.13 No.5

A fractional folding analog-to-digital converter (ADC) with a novel arithmetic digital encoding technique is discussed. In order to reduce the asymmetry errors of the boundary conditions for the conventional folding ADC, a structure using an odd number of folding blocks and fractional folding rate is proposed. To implement the fractional technique, a new arithmetic digital encoding technique composed of a memory and an adder is described. Further, the coding errors generated by device mismatching and other external factors are minimized, since an iterating offset self-calibration technique is adopted with a digital error correction logic. A prototype 8-bit 1GS/s ADC has been fabricated using an 1.2V 0.13 um 1-poly 6-metal CMOS process. The effective chip area is $2.1mm^2$(ADC core : $1.4mm^2$, calibration engine : $0.7mm^2$), and the power consumption is 88 mW. The measured SNDR is 46.22 dB at the conversion rate of 1 GS/s. Both values of INL and DNL are within 1 LSB.

The Strategy-Environment Match and Performance in Two Technological Settings : An Empirical Study in the Korean Textile Industry 韓國의 纖維産業 實證硏究

Lee, Jangwoo 慶北大學校 經濟經營硏究所 1993 經商論集 Vol.21 No.2

A Study on the Revitalization of Forest Management by Improving the Implementation Rate of FOREST Projects

Jangwoo Lee,Giseok Kwon,Wookwang Cheon,Wonhyeon Lim J-INSTITUTE 2020 International Journal of Human & Disaster Vol.5 No.2

Purpose: Driven by the society’s demand arising from global climate change, privately owned forests in South Korea, which make up two thirds of the total forested area of the country, have been playing a pivotal role as sites of forest resource development and major carbon sink. Forest management plans serve as the basic plans for managing privately owned forests. Therefore, it is necessary to compare and check whether the forest manage-ment plans are well-prepared and whether the forestry projects based on the approved plans have been efficiently implemented and managed. This study was conducted to analyze forest owners’ views and demands through surveys, albeit at a regional level, with a view to providing basic data for establishing measures for improving future forestry policy. Such a policy framework for efficient private forest management should be based on efficient preparation of forest man-agement plans and their evaluation through correct methods. Method: Therefore, this study proposes measures for promoting private forest management by conducting survey-based analysis of private forest management plan preparation and the ratio of forestry project implemen-tation with respect to the approval status. Results: To enable a proper prediction of future forest changes and ensure sustainable forest management through the proposed measures, a reliable evaluation of the general issues related to forest project implementa-tion was performed from the perspective of forest owners. Conclusion: The significance of this study lies in proposing measures to promote private forest management, and it is expected to offer opportunities to private forest owners to manage their private forests more efficiently.