• Title/Summary/Keyword: A375-S2

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Evaluation of delamination in the drilling of CFRP composites

  • Feroz, Shaik;Ramakrishna, Malkapuram;K. Chandra, Shekar;P. Dhaval, Varma
    • Advances in materials Research
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    • v.11 no.4
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    • pp.375-390
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    • 2022
  • Carbon Fiber Reinforced Polymer (CFRP) composite provides outstanding mechanical capabilities and is therefore popular in the automotive and aerospace industries. Drilling is a common final production technique for composite laminates however, drilling high-strength composite laminates is extremely complex and challenging. The delamination of composites during the drilling at the entry and exit of the hole has a severe impact on the results of the holes surface and the material properties. The major goal of this research is to investigate contemporary industry solutions for drilling CFRP composites: enhanced edge geometries of cutting tools. This study examined the occurrence of delamination at the entry and exit of the hole during the drilling. For each of the 80°, 90°, and 118°point angle uncoated Brad point, Dagger, and Twist solid carbide drills, Taguchi design of experiments were undertaken. Cutting parameters included three variable cutting speeds (100-125-150 m/min) and feed rates (0.1-0.2-0.3 mm/rev). Brad point drills induced less delamination than dagger and twist drills, according to the research, and the best cutting parameters were found to be a combination of maximum cutting speed, minimum feed rate, and low drill point angle (V:150 m/min, f: 0.1 mm/rev, θ: 80°). The feed rate was determined to be the most efficient factor in preventing hole entry and exit delamination using analysis of variance (ANOVA). Regression analysis was used to create first-degree mathematical models for each cutting tool's entrance and exit delamination components. The results of optimization, mathematical modelling, and experimental tests are thought to be reasonably coherent based on the information obtained.

Molecular characterization and functional analysis of a protease-related protein in Chang-liver cells

  • Wang, Congrui;Zhang, Huiyong;Feng, Huigen;Yang, Baosheng;Pramanik, Jogenananda;Guo, Zhikun;Lin, Juntang
    • BMB Reports
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    • v.43 no.5
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    • pp.375-381
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    • 2010
  • In this study, the cDNA library of Chang-liver cells was immunoscreened using common ADAMs antibody to obtain ADAM related genes. We found one positive clone that was confirmed as a new gene by Blast, which is an uncharacterized helical and coil protein and processes protease activity, and named protease-related protein 1 (ARP1). The submitted GenBank accession number is AY078070. Molecular characterizations of ARP1 were analyzed with appropriate bioinformatics software. To analyse its expression and function, ARP1 was subcloned into glutathione S-transferase fusion plasmid pGEX-2T and expressed by E. coli system. The in vitro expression product of ARP1 was recognized by common ADAMs antibody with western blot. Interestingly, ARP1 cleaves gelatine at pH9.5, which suggests it is an alkaline protease. Semi-quantitative RT-PCR result indicates that ARP1 mRNA is strongly transcribed in the liver and the treated Chang-liver cells.

Parenting Stress, Depression and Verbal Abuse of Infant's Mothers (영유아 어머니의 양육스트레스, 우울 및 언어적 학대)

  • Kim, Mi-Ye;Park, Dong-Young
    • Child Health Nursing Research
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    • v.15 no.4
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    • pp.375-382
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    • 2009
  • Purpose: The purpose of this study was to examine the relation between parenting stress and depression in mothers of infants and verbal abuse. Methods: The data for this study was collected from 174 mothers of infants 12 to 48 months old who either used one of two pediatric clinics or one kindergarten. The instruments used for this study were a self-report questionnaire, PSI (Parenting Stress Index Short Form by Abidin), BDI (Beck Depression Instrument) and Verbal Abuse Measure. Regression analysis was the statistical method used for data analysis. Results: The mean score for depression in the mothers was 14.7 (range: 2-35), for parenting stress, 81.86 (range: 44-142), and for verbal abuse, 37.9 (range: 25-79). There were significant positive correlations for depression, parenting stress and verbal abuse in the mothers. Significant factors influencing verbal abuse were child domain, parent-child domain. Conclusion: The results of this study suggest that there is a need to design interventions and develop programs for depression management and parenting stress for mothers of infants between 12 and 48 months.

Factors Influencing Depression among Married Vietnamese Immigrant Women: Using Data from the 2018 National Survey of Multicultural Families (베트남 결혼이주여성의 우울감 영향요인: 2018년 전국다문화가족실태조사를 중심으로)

  • Lee, Ga Eon;Jun, Hye Jung
    • Journal of Korean Public Health Nursing
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    • v.36 no.3
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    • pp.375-388
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    • 2022
  • Purpose: The purpose of this study was to identify the factors influencing depression among married Vietnamese immigrant women living in Korea. Methods: This study was a retrospective review of the dataset from the Korean 2018 National Multicultural Family Survey. The data were analyzed using the Rao-Scott x2 test and multiple logistic regression using complex samples analysis. Results: The proportion of married Vietnamese immigrant women subjects in Korea who experienced depression was 27.7%. The factors affecting depression were age, length of stay in Korea, living area, economic status, difficulties in using medical care, difficulties faced during their stay in Korea and Korean language skills relationship with spouse and parents-in-law marital conflicts, cultural differences, their experience of social discrimination, life satisfaction, and meeting with friends from their homeland. Conclusion: The findings in this study indicate that the prevention of depression in married immigrant women in Korea could be aided by acculturation programs that deal with the relationships with their spouses and social supports.

Effect of Polyherbal Feed Supplement "Growell" during Induced Aflatoxicosis, Ochratoxicosis and Combined Mycotoxicoses in Broilers

  • Kalorey, D.R.;Kurkure, N.V.;Ramgaonkar, J.S.;Sakhare, P.S.;Warke, Shubhangi;Nigot, N.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.3
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    • pp.375-383
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    • 2005
  • An experiment was conducted to study the protective role of polyherbal feed supplement (Growell) during induced mycotoxicosis in broilers. A total of 240 Vencobb broilers were divided at day old stage into eight equal groups. Group A served as control and was given plain feed, group B, D, F and H were given Growell at 0.35 g/kg of feed. Group C, D, G and H were given dietary aflatoxin $B_1$ at 0.2 ppm and groups E, F, G and H were given ochratoxin A at 0.2 ppm in feed to study effect of Growell on individual aflatoxicosis, ochratoxicosis and combined mycotoxicosis of broilers. The chicks were given their respective feeds from 1st day to 6th week of age and were vaccinated at 7th and 28th day of age with Lasota strain of Newcastle disease virus. There was no statistically significant effect of mycotoxins individually or in combination on body weight of broilers. However, body weights were highest in group B and lowest in co-mycotoxicated group G. Feed conversion ratio was best in group B followed by A, D, F, E, H and G. Significant improvement in haemoglobin values was observed in broilers due to feeding of Growell in ochratoxin and co-mycotoxicated groups. There was no significant effect of mycotoxin treatment on PCV, TEC and TLC of broilers. Due to single and combined mycotoxicosis, there was reduction in serum total protein, albumin, cholesterol and triglyceride and rise in alkaline phosphatase, creatinine and uric acid levels. Supplementation of diets with Growell reduced the alterations induced due to mycotoxins. There was a significant rise in per cent organ weight of liver and reduction of that of spleen, bursa of Fabricius and thymus of broilers fed mycotoxins. Protection from alteration in per cent organ weight of these organ by supplementation of Growell was recorded. The observed impaired immune response and histopathological changes in liver, kidney, spleen, bursa of Fabricius and thymus of broilers given mycotoxins were protected by supplementation of Growell.

Integration of computer-based technology in smart environment in an EFL structures

  • Cao, Yan;AlKubaisy, Zenah M.
    • Smart Structures and Systems
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    • v.29 no.2
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    • pp.375-387
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    • 2022
  • One of the latest teaching strategies is smart classroom teaching. Teaching is carried out with the assistance of smart teaching technologies to improve teacher-student contact, increase students' learning autonomy, and give fresh ideas for the fulfillment of students' deep learning. Computer-based technology has improved students' language learning and significantly motivating them to continue learning while also stimulating their creativity and enthusiasm. However, the difficulties and barriers that many EFL instructors are faced on seeking to integrate information and communication technology (ICT) into their instruction have raised discussions and concerns regarding ICT's real worth in the language classroom. This is a case study that includes observations in the classroom, field notes, interviews, and written materials. In EFL classrooms, both computer-based and non-computer-based activities were recorded and analyzed. The main instrument in this study was a survey questionnaire comprising 43 items, which was used to examine the efficiency of ICT integration in teaching and learning in public schools in Kuala Lumpur. A total of 101 questionnaires were delivered, while each responder being requested to read the statements provided. The total number of respondents for this study was 101 teachers from Kuala Lumpur's public secondary schools. The questionnaire was randomly distributed to respondents with a teaching background. This study indicated the accuracy of utilizing Teaching-Learning-Based Optimization (TLBO) in analyzing the survey results and potential for students to learn English as a foreign language using computers. Also, the usage of foreign language may be improved if real computer-based activities are introduced into the lesson.

Diffusion Coefficient of Iron in ZnSe Polycrystals from Metal Phase for mid-IR Gain Medium Application

  • Jeong, Junwoo;Myoung, NoSoung
    • Applied Science and Convergence Technology
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    • v.23 no.6
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    • pp.371-375
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    • 2014
  • Diffusion coefficient of Fe in polycrystalline host ZnSe as a mid-IR gain medium has been measured in the annealing temperature ranges of 850 to $950^{\circ}C$. The synthesis of the samples was carried out in quartz ampoule in which the Fe thin film deposited by physical vapor evaporation method on the ZnSe. One can realize that the diffusion coefficient strongly depends on the surface active surfactants through the cleaning process and the substrate temperature during the thin film deposition leading to $2.04{\times}10^{-9}cm^2/s$ for $Fe^{2+}:ZnSe$. The Annealing temperature dependence of the Fe ions diffusion in ZnSe was used to evaluate the activation energy, $E_a$=1.39 eV for diffusion and the pre-exponential factor $D_0$ of $13.5cm^2/s$.

Transgenic Rice Plants Expressing an Active Tobacco Mitogen-activated Protein Kinase Kinase Induce Multiple Defense Responses

  • Jeong, Jin-A;Yoo, Seung-Jin;Yang, Douck-Hee;Shin, Seo-Ho;Lee, Myung-Chul;Cho, Baik-Ho;Yang, Kwang-Yeol
    • The Plant Pathology Journal
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    • v.24 no.4
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    • pp.375-383
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    • 2008
  • It is well known that NtMEK2, a tobacco MAPK kinase, is the upstream kinase of both salicylic acid-induced protein kinase and wound-induced protein kinase. In addition, expression of $NtMEK2^{DD}$, a constitutively active mutant of NtMEK2, is known to induce multiple defense responses in tobacco. In this study, transgenic rice plants that contained an active or inactive mutant of NtMEK2 under the control of a steroid inducible promoter were generated and used to determine if a similar MAPK cascade is involved in disease resistance in rice. The expression of $NtMEK2^{DD}$ in transgenic rice plants resulted in HR-like cell death. The observed cell death was preceded by the activation of endogenous rice 48-kDa MBP kinase, which is also activated by Xanthomonas oryzae pv. oryzae, the bacterial blight pathogen of rice. In addition, prolonged activation of the MAPK induced the generation of hydrogen peroxide and up-regulated the expression of defense-related genes including the pathogenesis-related genes, peroxidases and glutathione S-transferases. These results demonstrate that NtMEK2 is functionally replaceable with rice MAPK kinase in inducing the activation of the downstream MAPK, which in turn induces multiple defense responses in rice.

Current Carrying Iron Whiskers: A New Magnetic Configuration

  • Lee, J.G.;Arrott, A.S.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.372-375
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    • 1995
  • The magnetization pattern of the central cross section deduced from the ac susceptibility measurement is described with an analytical function. The function is based on a charge-free configuration. The thickness of the $^{\circ}$ wall lying in a (100) plane and the wall energy are calculated analytically. Total energy of the domain structure has been minimized with Ritz's method. As the result of the minimization, the energy density of the $^{\circ}$ wall lying in a (100) plane is $0.58\;erg/cm^{2}$ and the one for a (110) plane is $1.18\;erg/cm^{2}$. Thicknesses of these walls are calculated numerically. Also, the calculation indicates there is a small central domain at the cross section without applied current. With the ac susceptibility measurement the existence of the domain without current can be identified.

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Experimental Study of Steam Reforming Assisted by Catalytic Combustion in Concentric Annular Reactor (촉매연소를 이용한 동심 원관형 반응기 내의 수증기 개질 반응에 관한 실험적 연구)

  • Ghang, Tae-Gyu;Yu, Sang-Seok;Kim, Yong-Mo;Ahn, Kook-Young
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.4
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    • pp.375-381
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    • 2010
  • In this paper, the heat-transfer characteristics of steam reforming in an annular reactor are presented. Heat is supplied by the catalytic combustion of syn-gas. The thermal behaviors of exothermic and endothermic reactions in a directly coupled concentric-tube packed-bed reactor were investigated experimentally. The gas mixture supplied for catalytic combustion consisted of the off-gas emitted from MCFC anode. Methane in steam at a suitable S/C (steam-to-carbon) ratio was used in the reforming reactions. On the basis of the experimental results, a simple simulation was performed to predict the temperature profile required in the reforming side of the reactor to achieve optimum hydrogen yield. The results of this study may be utilized as reference data in future studies for further development of coupled reactors.