• Title/Summary/Keyword: ${\alpha}$-limit

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Application of Bootstrap and Bayesian Methods for Estimating Confidence Intervals on Biological Reference Points in Fisheries Management (부트스트랩과 베이지안 방법으로 추정한 수산자원관리에서의 생물학적 기준점의 신뢰구간)

  • Jung, Suk-Geun;Choi, Il-Su;Chang, Dae-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.41 no.2
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    • pp.107-112
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    • 2008
  • To evaluate uncertainty and risk in biological reference points, we applied a bootstrapping method and a Bayesian procedure to estimate the related confidence intervals. Here we provide an example of the maximum sustainable yield (MSY) of turban shell, Batillus cornutus, estimated by the Schaefer and Fox models. Fitting the time series of catch and effort from 1968 to 2006 showed that the Fox model performs better than the Schaefer model. The estimated MSY and its bootstrap percentile confidence interval (CI) at ${\alpha}=0.05$ were 1,680 (1,420-1,950) tons for the Fox model and 2,170 (1,860-2,500) tons for the Schaefer model. The CIs estimated by the Bayesian approach gave similar ranges: 1,710 (1,450-2,000) tons for the Fox model and 2,230 (1,760-2,930) tons for the Schaefer model. Because uncertainty in effort and catch data is believed to be greater for earlier years, we evaluated the influence of sequentially excluding old data points by varying the first year of the time series from 1968 to 1992 to run 'backward' bootstrap resampling. The results showed that the means and upper 2.5% confidence limit (CL) of MSY varied greatly depending on the first year chosen whereas the lower 2.5% CL was robust against the arbitrary selection of data, especially for the Schaefer model. We demonstrated that the bootstrap and Bayesian approach could be useful in precautionary fisheries management, and we advise that the lower 2.5% CL derived by the Fox model is robust and a better biological reference point for the turban shells of Jeju Island.

The Effect of Education on the Knowledge and Attitude toward Child Sexual Abuse in Kindergarten Teachers in Korea (어린이 성폭력 예방 교육이 유치원 교사의 지식 및 태도에 미치는 효과)

  • Bae, Jeong-Iee
    • The Journal of Korean Academic Society of Nursing Education
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    • v.7 no.2
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    • pp.254-263
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    • 2001
  • The Purpose of this study was to find out the effects of education for prevention of sexual abuse (rape, sexual assault, sexual harassment etc.) of children in kindergarten teachers. Incidences of sexual abuse in Korea is ranked 3rd in the world. Sexual abuse of children, particularly, is one of the most serious crimes that affect both the victimized children and their family. The issue related to sexual abuse of children has been ignored, and there is a lack of systematic education to prevent sexual abuse of children either for children or their parents in Korea. Furthermore, lack of knowledge and poor attitude of teachers limit their capability to provide education for sexual abuse prevention to the children. The education for kindergarten teachers may change their knowledge of the sexual abuse and their attitude toward it and improve their capability in helping children. 114 Korean kindergarten teachers participated in this study. Research design was one group pretest-posttest design. The education given to the subjects included 2 hours of lecture. The education program was developed based on a survey. Preschool-aged-children, parents, and teachers were interviewed to reveal their educational needs based on their experiences related to sexual abuse. This program includes such as safety education, crisis management, resource person(s), and phone numbers of available hospital. Data was collected before and after the education was given to the subjects, to assess their knowledge and attitude toward child sexual abuse. Two instruments were used in this study. Using Cronbach's ALPHA validity and reliability of 2 instruments were tested. The analysis of the data was done with Window SPSS 10.0 for descriptive statistics, t-test and ANOVA. The results of this analysis were as follows : 1. After education, the score of kindergarten teachers knowledge was higher than before (t=-4.409, p=0.002). 2. After education, the score of kindergarten teachers attitude was higher than before (t=3.065, p=0.003). The findings from this study will provide an intervention strategy for prevention of sexual abuse in children.

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Mössbauer Study of Ti0.9957Fe0.01O2

  • Kim, Eng-Chan;Moon, S.H.;Woo, S.I.;Kim, H.D.;Kim, B.Y.;Cho, J.H.;Joh, Y.G.;Kim, D.H.
    • Journal of the Korean Magnetics Society
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    • v.15 no.2
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    • pp.106-108
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    • 2005
  • The rutile polycrystal $Ti_{0.99}\;^{57}Fe_{0.01}O_2$ prepared with $^{57}Fe$ enriched iron have been studied by $M\ddot{o}ssbauer$ spectroscopy, X-ray diffraction and VSM. The $M\ddot{o}ssbauer$ spectrum of $Ti_{0.99}\;^{57}Fe_{0.01}O_2$ consists of a ferromagnetic and a paramagnetic phase over all temperature ranging from 4 to 300 K. Isomer shifts indicate $Fe^{2+}$ for the ferromagnetic phase, but $Fe^{3+}$ for the paramagneic phase of $Ti_{0.99}\;^{57}Fe_{0.01}O_2$ sample. It is noted that the magnetic hyperfine field of ferromagnetic phase had the value about 1.48 times as large as that of $\alpha$-Fe. The XRD data for $Ti_{0.99}\;^{57}Fe_{0.01}O_2$ showed a pure rutile phase with tetragonal structures without any segregation of Fe into particulates within the instrumental resolution limit The magnetic hysteresis (M-H) curve at room temperature showed an obvious ferromagnetic behavior and the magnetic moment per Fe atom under the applied field of 1 T was estimated to be about $0.71{\mu}_B$, suggesting a low spin configuration of Fe ions.

Enantioselective Determination of Cetirizine in Human Urine by HPLC

  • Choi, Sun-Ok;Lee, Seok-Ho;Kong, Hak-Soo;Kim, Eun-Jung;Parkchoo, Hae-Young
    • Archives of Pharmacal Research
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    • v.23 no.2
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    • pp.178-181
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    • 2000
  • In order to study the simultaneous determination of (+)- and (-)-cetirizine in human urine we have developed a chiral separation method by HPLC. A chiral stationary phase of $\alpha$$_1$-acidglycoprotein, the AGP-CSP was used to separate the enantiomers. The pH of the phosphate buffer, as well as the content of the organic modifier in the mobile phase, markedly affected the chromatographic separation of (+)- and (-)-cetirizine. A mobile phase of 10 m㏖/1 phosphate buffer (pH 7.0)-acetonitrile (95 : 5, v/v) was used for the urine assays. Ultraviolet absorption was monitored at 230nm and roxatidine was employed as the internal standard for quantification. (+)-Cetirizine, (-)-cetirizine and the internal standard were eluted at retention times of 12, 16, and 32 mins, respectively. The detection limit for cetirizine enantiomers was 400 ng/$m\ell$ of urine. A pharmacokinetic study was conducted with the help of 5 healthy female volunteers who were administered with a single oral dose of racemic cetirizine (20 mg). The peak area ratios provided by the cetirizine enantiomers were linear(r>0.997) over a concentration range of 2.5-200 ${\mu}g/ml$. The peak of the excreted cetirizine enantiomers appeared in the urine sample during the period of 1-2 hrs following the administration of the oral dose. The excreted level of (+)-cetirizine was slightly higher than (-)-cetirizine but the difference was not statistically significant. However, this method appears to have applications for enantioselective pharmacokinetic studies of racemic drugs.

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Bioconversion of Piceid to Piceid Glucoside Using Amylosucrase from Alteromonas macleodii Deep Ecotype

  • Park, Hyunsu;Kim, Jieun;Park, Ji-Hae;Baek, Nam-In;Park, Cheon-Seok;Lee, Hee-Seob;Cha, Jaeho
    • Journal of Microbiology and Biotechnology
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    • v.22 no.12
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    • pp.1698-1704
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    • 2012
  • Resveratrol, or its glycoside form piceid, is a dietary antioxidant polyphenolic compound, found in grapes and red wine that has been shown to have protective effects against cardiovascular disease. However, very low water solubility of the compound may limit its application in the food and pharmaceutical industries. The amylosucrase (AMAS) of Alteromonas macleodii Deep ecotype was expressed in Escherichia coli and showed high glycosyltransferase activity to produce the glucosyl piceid when piceid was used as an acceptor. The conversion yield of piceid glucoside was 35.2%. Biotransformation using culture of the E. coli harboring the amas gene increased the yield up to 70.8%. The transfer product was purified by reverse phase chromatography and recycling preparative HPLC, and the molecular structure of the piceid glucoside was determined using NMR spectroscopy. The piceid glucoside was identified as glucosyl-${\alpha}$-($1{\rightarrow}4$)-piceid. The solubility of glucosyl piceid was 5.26 and 1.14 times higher than those of resveratrol and piceid, respectively. It is anticipated that dietary intake of this compound is more effective by enhancing the bioavailability of resveratrol in the human body because of its hydrophilic properties in the intestinal fluid.

Theoretical Analysis on the Velocity Profile of Newtonian Fluids within Modelled Asymmetric Membrane Pores (모델화한 비대칭형 막기공에서 뉴톤 유체의 속도분포에 관한 이론해석)

  • 전명석;김재진
    • Membrane Journal
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    • v.7 no.3
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    • pp.142-149
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    • 1997
  • The extended analysis on the diverging flow through asymmetric membrane pores has been performed in this study. Afore rigorous equations of velocity profile relevant to the divergent slit and cone shaped channels, which are widely used as a general pore model, have been obtained by employing a creeping flow approach of Newtonian fluids. As a degree of asymmetry (i.e., diverging angle) is increased, the predicted flow function shifts Toward the center region due to the incorporated wall effect, so that the overall velocity profile becomes decreased. It is true, as expected, that when the divergent channel is in the low diverging angle limit, the channel flow results in the Poiseuillean fashion by utilizing a lubrication approximation. The flow rate equation of each type of channel has been developed from the combined solution of velocity profile and pressure fields. The effect of diverging flow on the flow rate enhancement has been remarkably predicted, in which the flow rate increases with the increase of pore asymmetry. The advantage of our theoretical results lies in the analytical expression for the diverging flow behavior through pore channels as well as its ability to play a fundamental role on the related membrane filtrations such as microfiltration and ultrafiltration.

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Radiochemical Analysis of Filters Used During the Decommissioning of Research Reactors for Disposal

  • Kyungwon Suh;Jung Bo Yoo;Kwang-Soon Choi;Gi Yong Kim;Simon Oh;Kanghyun Yoo;Kwang Eun Lee;Shinkyoung Lee;Young Sang Lee;Hyeju Lee;Junhyuck Kim;Kyunghun Jung;Sora Choi;Tae-Hong Park
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.20 no.4
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    • pp.489-500
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    • 2022
  • The decommissioning of nuclear facilities produces various types of radiologically contaminated waste. In addition, dismantlement activities, including cutting, packing, and clean-up at the facility site, result in secondary radioactive waste such as filters, resin, plastic, and clothing. Determining of the radionuclide content of this waste is an important step for the determination of a suitable management strategy including classification and disposal. In this work, we radiochemically characterized the radionuclide activities of filters used during the decommissioning of Korea Research Reactors (KRRs) 1 and 2. The results indicate that the filter samples contained mainly 3H (500-3,600 Bq·g-1), 14C (7.5-29 Bq·g-1), 55Fe (1.1- 7.1 Bq·g-1), 59Ni (0.60-1.0 Bq·g-1), 60Co (0.74-70 Bq·g-1), 63Ni (0.60-94 Bq·g-1), 90Sr (0.25-5.0 Bq·g-1), 137Cs (0.64-8.7 Bq·g-1), and 152Eu (0.19-2.9) Bq·g-1. In addition, the gross alpha radioactivity of the samples was measured to be between 0.32-1.1 Bq·g-1. The radionuclide concentrations were below the concentration limit stated in the low- and intermediatelevel waste acceptance criteria of the Nuclear Safety and Security Commission, and used for the disposal of the KRRs waste drums to a repository site.

Factors Affecting Mobile Payment Acceptance and Intention: A Case Study of Hospitality Customers in Vietnam

  • PHAN, Dinh Tram Anh;NGUYEN, Thi Thuy Ngan;NGUYEN, Thi Khanh Nhi;NGUYEN, Tran Thien An;PHAN, Van Si Dan;HO, Ngoc Phuong Thao;DO, Kim Xuan;NGUYEN, Trong Luan
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.5
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    • pp.29-39
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    • 2022
  • The outbreak of the COVID-19 pandemic has had a significant impact on the Vietnamese economy. In the midst of a complex disease that compelled people to limit their interaction, customers' shopping habits shifted from "offline" to "online" transactions. Mobile payments have also grown in popularity. The goal of this study is to figure out what factors influence the use of mobile payments by hotel clients in Can Tho after COVID-19. The research team also examines how those factors influence customers' willingness to use mobile payment and makes recommendations to better the current situation. Primary data was collected from 227 persons using online surveys and processed with SPSS software for this study. To analyze the correlation relationship between the elements determining the intention to use, the Cronbach alpha, EFA, Correlation, and Regression methods used to assess the scale are applied. Perceived Trustworthiness, Perceived Usefulness, and Perceived Ease of Use all have positive effects on customers' propensity to use, according to the findings. Perceived Security, on the other hand, has no bearing. The findings of this study have significant theoretical and practical implications for the development of mobile payment services in Can Tho, particularly following the implementation of COVID-19.

Determination of Polycyclic Aromatic Hydrocarbons in Smoked Food Products (훈연식품 중 polycyclic aromatic hydrocarbons 함량 분석)

  • Seo, Ilwon;Nam, Hejung;Lee, Songyoung;Lee, Kyueun;Shin, Han-Seung
    • Food Engineering Progress
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    • v.13 no.3
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    • pp.195-202
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    • 2009
  • This study was accomplished that analysis of seven polycyclic aromatic hydrocarbons (PAHs) in smoked or nonsmoked processing foods by high performance liquid chromatography (HPLC) with fluorescence detection. The calibration line was constructed with injected different levels of standard concentration. Limit of detection (LOD) and limit of quantification(LOQ) showed higher linearity ($r^{2}$=0.998) reasonably, and recovery exhibited 0.033-0.666 $\mu$g/kg, 0.108-2.217 $\mu$g/kg and 69.31-90.14%, respectively. As a result, the samples using smoked tuna as smoked materials contained seven PAHs with different range from 0.256 to 0.486 $\mu$g/kg. The benzo[a]pyrene, indicator of PAHs, was detected to below the LOQ in two samples. Concentrations of benzo[a]pyrene in three samples were below the 2 $\mu$g/kg which is the limit of regulation. Smoked tuna sauces were detected from 0.321 to 0.552 $\mu$g/kg and not detected in drying powders. PAHs of smoked meat products were ranged from 0.720 to 2.027 $\mu$g/kg and are higher than concentration of tuna smoked samples. PAHs were very low in non-smoked foods including mustard, herb, and roasted meats.

Exposure Assessment of Pesticide-Originated Persistent Organic Pollutants in Paddy and Upland Soils in Korea (국내 논토양 및 밭토양 중 농약유래 잔류성유기오염물질의 노출량 평가)

  • Lim, Sung-Jin;Oh, Young-Tak;Ro, Jin-Ho;Kim, Seung-Yong;Joo, Hyeong-Gon;Lee, Min-Ho;Yoon, Hyo-In;Choi, Geun-Hyoung;Ryu, Song-Hee;Park, Byung-Jun
    • Korean Journal of Environmental Agriculture
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    • v.36 no.3
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    • pp.211-216
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    • 2017
  • BACKGROUND:This study was conducted to investigate residual organochlorine pesticides (ROCPs) in agricultural soils and crops. Agricultural soil samples and crop samples were collected from 93 cities and counties. METHODS AND RESULTS: Extraction and clean-up for the quantitative analysis of ROCPs were conducted by the modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) method. Recovery and limit of detection (LOD) of ROCPs in agriculturalsoils and crops were 76.5-103.0 and 75.2-93.2%, 0.01-0.08 and $0.10-0.15{\mu}g/kg$, respectively. Detected ROCPs in agricultural soils were ${\alpha}$-endosulfan, ${\beta}$-endosulfan, and endosulfan sulfate, the residue were 2.0-12.0, 1.2-53.1, and $2.2-329.8{\mu}g/kg$, respectively. But these pesticides in all green perilla leaf and green pepper samples were not detected. CONCLUSION: These results showed that ROCPs residues in agricultural soils were not as high as crop safety threatening.