http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Efficient Neural Network Design for Identifying Potential Game Item Buyers
Soohyung Lee 한국지능시스템학회 2022 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.22 No.3
As competition in the mobile game market continues to intensify, the number of users accessingspecific games is decreasing, and marketing costs are rising significantly. Marketing methodsto increase average revenue per user (ARPU) are being improved accordingly. In this study,we present a method for predicting the future purchases of new users who start playingmobile games. The proposed system enables effective marketing based on the purchasingpropensity of a user over a short period of time. In the game data, the proportion of nonpurchasers compared to purchasers is extremely large because the number of purchasers issmall when the game is first released. Therefore, this study use an under-sampling methodto handle the unbalanced data. The loss functions used in neural networks are customizedto learn a neural network with a high probability that a predicted purchaser will be an actualpurchaser. Experiments show that proposed method can predict the purchasing propensityover a month-long period using the 7-day data of a new user.
Lee, Theresa,Lee, Seung-Ho,Shin, Jean Young,Kim, Hee-Kyoung,Yun, Sung-Hwan,Kim, Hwang-Yong,Lee, Soohyung,Ryu, Jae-Gee The Korean Society of Plant Pathology 2014 Plant Pathology Journal Vol.30 No.1
Nivalenol (NIV) and deoxynivalenol (DON) are predominant Fusarium-producing mycotoxins found in grains, which are mainly produced by Fusarium asiaticum and F. graminearum. NIV is found in most of cereals grown in Korea, but the genetic basis for NIV production by F. asiaticum has not been extensively explored. In this study, 12 genes belonging to the trichothecene biosynthetic gene cluster were compared at the transcriptional level between two NIV-producing F. asiaticum and four DON-producing F. graminearum strains. Chemical analysis revealed that time-course toxin production patterns over 14 days did not differ between NIV and DON strains, excluding F. asiaticum R308, which was a low NIV producer. Both quantitative real-time polymerase chain reaction and Northern analysis revealed that the majority of TRI gene transcripts peaked at day 2 in both NIV and DON producers, which is 2 days earlier than trichothecene accumulation in liquid medium. Comparison of the gene expression profiles identified an NIV-specific pattern in two transcription factor-encoding TRI genes (TRI6 and TRI10) and TRI101, which showed two gene expression peaks during both the early and late incubation periods. In addition, the amount of trichothecenes produced by both DON and NIV producers were correlated with the expression levels of TRI genes, regardless of the trichothecene chemotypes. Therefore, the reduced production of NIV by R308 compared to NIV or DON by the other strains may be attributable to the significantly lower expression levels of the TRI genes, which showed early expression patterns.
Soohyung Lee,Inkyu Yoo,Jisoo Han,Wonchul Jung,Hakhyun Ka 한국동물생명공학회(구 한국동물번식학회) 2018 발생공학 국제심포지엄 및 학술대회 Vol.2018 No.06
Estrogen is essential for reproductive processes such as maturation of ovarian follicles, embryo implantation, placentation, lactation, parturition, sexual differentiation, and sexual behavior in females. Generally estrogen binds to nuclear receptors, estrogen receptor alpha (ERα) and beta (ERβ). Recently, novel estrogen receptor, G protein- coupled estrogen receptor 1 (GPER1), has been identified and shown to be expressed in the plasma membrane. However, the expression and regulation of GPER1 has not been determined in the female reproductive system in pigs. Thus, this study determined the expression of GPER1 in the endometrium during the estrous cycle and pregnancy in pigs. We obtained endometrial tissues from gilts on day (D) 0, D3, D6, D9, D12, D15 and D18 of the estrous cycle and on D12, D15, D30, D60, D90 and D114 of pregnancy, and chorioallantoic tissues on D30, D60, D90 and D114 of pregnancy. GPER1 mRNA was expressed in the endometrium during the estrous cycle and pregnancy in pigs. During the estrous cycle, GPER1 expression was higher in diestrus and proestrus than in estrus and metestrus. During pregnancy, GPER1 mRNA was high during the preimplantation period and low during mid- to late pregnancy. Expression of GPER1 was significantly higher on D15 of the estrous cycle than D15 of pregnancy. RT-PCR analysis showed that GPER1 mRNA was not detectable in conceptus on D12 and D15 of pregnancy. In chorioallantoic tissues, GPER1 mRNA increased toward term pregnancy. Endometrial explant culture study showed that the expression of GPER1 mRNA was down-regulated by increasing doses of progesterone but not affected by estradiol. In situ hybridization analysis showed that GPER1 mRNA was localized to luminal epithelial cells in the endometrium on D15 of estrous cycle. These results indicate that GPER1 mRNA is expressed in the endometrium during the estrous cycle and pregnancy in a stage- and pregnancy status-dependent manner, suggesting that GPER1 may play an important role in mediating estrogen actions of the maternal-fetal interface in pigs. Further analysis of signaling pathway and function of GPER1 in the reproductive system is needed.
Adsorption of acetaldehyde from air by activated carbon and carbon fibers
Soohyung Park,Muhammad Yaqub,Seunghan Lee,Wontae Lee 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.2
The adsorption of acetaldehyde from air using various activated carbon and carbon fibers was investigated in this study. These adsorbents included activated carbon (AC), carbon fibers (CFs), activated carbon fibers (ACFs), and metal-coated carbon fibers (MCCFs) supplied by different manufacturers. AC was categorized as AC₁, AC₂, AC₃, and AC₄, CFs were denoted as ACF₁, while ACFs and MCCFs were expressed as ACF₂ and ACF₃, respectively. Five composite materials were prepared using the AC and ACFs in different ratios, and experiments were conducted to assess their acetaldehyde adsorption efficiency under dry and wet conditions. The results showed that the acetaldehyde adsorption efficiency of an impregnated AC₄ was higher (95.9%) than that of both non-impregnated AC₁ and AC₃ and an impregnated AC₂ after 1 min of operation. ACF₂ showed a higher acetaldehyde adsorption efficiency (50.9%) as compared to ACF₁ and ACF₃ because of its larger surface area and selective absorption capability after 1 min of operation. A composite material comprising 6.3 g of AC₄ and 1 g of ACF₂ showed the highest adsorption efficiency of 97.9% under dry conditions. However, this adsorption efficiency significantly decreased under wet conditions.
Does Ramadan Harm Infant Health? Evidence from Ethiopia
Lee Soohyung,Nam Minhyuk,Jeong Daeun,Lee Wonmoon 한국국제경제학회 2020 International Economic Journal Vol.34 No.4
We examine the impact of religious practices on human capital in the context of Ethiopia. We focus on Ramadan, which leads mothers to reduce nutritional intake during the daytime. By exploiting the variation in the extent to which infants were exposed to Ramadan, we estimate the relative disadvantage of Muslim children compared to their non-Muslim counterparts. We find that the exposure to Ramadan in the first trimester has a significant negative effect on the infants’ health outcomes, but not on later life outcomes.
Impact of the Clean Air Act on Air Pollution and Infant Health:
Soohyung Lee(이수형),Heesun Yoo(유희선),Minhyuk Nam(남민혁) 한국재정학회(구 한국재정·공공경제학회) 2018 한국재정학회 학술대회 논문집 Vol.2018 No.-
This paper examines the extent to which the 2005 Clean Air Act introduced in South Korea affected air pollution and infant health. To identify the causal effect, we exploit the time and geographical variations in the adoption of the Act between 2003 and 2006. During this period, the Clean Air Act indeed significantly reduced air pollutants. The PM10 level was reduced by 9 percent, leading to a 5 percent reduction in infant mortality.
Occurrence of Toxigenic Fusarium vorosii among Small Grain Cereals in Korea
Lee, Theresa,Paek, Ji-Seon,Lee, Kyung Ah,Lee, Soohyung,Choi, Jung-Hye,Ham, Hyeonheui,Hong, Sung Kee,Ryu, Jae-Gee The Korean Society of Plant Pathology 2016 Plant Pathology Journal Vol.32 No.5
Fusarium graminearum species complex (FGSC) causes Fusarium head blight in small grain cereals. To date, four species (F. graminearum, F. asiaticum, F. boothii, and F. meridionale ) belonging to FGSC frequently occur in Korean cereals. In addition, we first reported the occurrence of additional species (F. vorosii ) within FGSC, which was isolated from barley, corn, and rice in Korea. Phylogenetic analysis of the Fusarium isolates of this group using combined multigene sequences confirmed species identification. Moreover, the macroconidia produced by these isolates were morphologically similar to those of the F. vorosii holotype. Chemical analysis indicated that the F. vorosii isolates produced various trichothecenes such as nivalenol and deoxynivalenol with their acetyl derivatives along with zearalenone. Pathogenicity tests demonstrated that all of the F. vorosii isolates examined were pathogenic on barley, corn, and rice with variation in aggressiveness. This study is the first report of F. vorosii in Korean cereals, their pathogenicity towards barley and corn, and their ability to produce trichothecenes and zearalenone.
( Soohyung Lee ),( Sang Moo Lee ) 한국축산학회 2021 한국축산학회지 Vol.63 No.5
This study examined the impact of using total mixed ration (TMR) and concentrate on feed intake, daily gain, carcass yield grade, and carcass quality grade of Hanwoo steers and its subsequent economic efficiency. Thirty six 7-month-old Hanwoo steers were assigned to one of the four treatment groups, and each group was divided into three repeated pens, with each repeated pen comprising three steers. The treatment groups were: 1) separate feeding with commercial concentrate and forage (namely, SCF) for the entire experimental period; 2) TMR feeding for a growing period followed by SCF for the early and late fattening period (namely, TMRGSCF); 3) TMR feeding for growing and an early fattening period followed by SCF for the late fattening period (namely, TMREFSCF); and 4) TMR feeding for the entire experimental period (namely, TMRW). The results showed that the SCF treatment had significantly (p < 0.05) higher feed intake during the growing period than other treatments. In contrast, the total feed intake had little difference during early and late fattening as well as the whole period regardless of feeding strategies. Daily gain showed no difference during the growing period. However, it was significantly higher in SCF and TMREFSCF treatments for the early and late fattening period, respectively (p < 0.05). The daily gain during the total raising period is in the order of TMREFSCF > TMRGSCF > SCF > TMRW. Carcass characteristics, including carcass weight, loin eye muscle area, and carcass yield grade, did not significantly differ among different treatments. However, TMRW treatment, wherein TMR was fed for a long time, showed that the cold carcass weight was less compared with other treatments, but carcass yield grade was higher with thinner backfat. Backfat thickness was in the order of SCF > TMRGSCF > TMREFSCF > TMRW, showing that the thickness reduced with longer TMR feeding (p < 0.05). TMRGSCF, which numerically had a higher carcass quality grade, showed higher economic efficiency, whereas SCF showed low economic efficiency. In conclusion, it was more feasible to apply TMR strategy in the growing and early fattening period and then SCF for the early or late fattening period to improve carcass yield, quality grade, and economic efficiency.