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.

Inter-pin skew compensation method for 3.2Gbps/pin DDR4 SDRAM interface

Jangwoo Lee,Younghoon Kim,Changsik Yoo 대한전자공학회 2009 ITC-CSCC :International Technical Conference on Ci Vol.2009 No.7

For inter-pin skew reduction with fast operation time and minimum hardware increase in DDR4 SDRAM interface, an inter-pin skew compensation algorithm using SAR (Successive Approximation Register) is proposed. The proposed algorithm implemented in a 0.18㎛ CMOS process shows that all pins can be aligned in 324 cycles when preamble sequence operates at 400㎒.

A 45 nm 9-bit 1 GS/s High Precision CMOS Folding A/D Converter with an Odd Number of Folding Blocks

Lee, Seongjoo,Lee, Jangwoo,Song, Minkyu The Institute of Electronics and Information Engin 2014 Journal of semiconductor technology and science Vol.14 No.4

In this paper, a 9-bit 1GS/s high precision folding A/D converter with a 45 nm CMOS technology is proposed. In order to improve the asymmetrical boundary condition error of a conventional folding ADC, a novel scheme with an odd number of folding blocks is proposed. Further, a new digital encoding technique is described to implement the odd number of folding technique. The proposed ADC employs a digital error correction circuit to minimize device mismatch and external noise. The chip has been fabricated with 1.1V 45nm Samsung CMOS technology. The effective chip area is $2.99mm^2$ and the power dissipation is about 120 mW. The measured result of SNDR is 45.35 dB, when the input frequency is 150 MHz at the sampling frequency of 1 GHz. The measured INL is within +7 LSB/-3 LSB and DNL is within +1.5 LSB/-1 LSB.

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.

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

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.

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>

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

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

JangWoo Lee,YoungLim Kho,SungKyoon Kim,Kyungho Choi,SeongHee Hwang,Jeeyeon Jeong,Pangyi Ki 한국환경보건학회 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 μg/kg bw/day, 3.5 μg/kg bw/day for DEHP and 4.9 μg/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.