• 제목/요약/키워드: Group Key

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Effects of Different Advance Organizers on Mental Model Construction and Cognitive Load Decrease

  • OH, Sun-A;KIM, Yeun-Soon;JUNG, Eun-Kyung;KIM, Hoi-Soo
    • Educational Technology International
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    • v.10 no.2
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    • pp.145-166
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    • 2009
  • The purpose of this study was to investigate why advance organizers (AO) are effective in promoting comprehension and mental model formation in terms of cognitive load. Two experimental groups: a concept-map AO group and a key-word AO group and one control group were used. This study considered cognitive load in view of Baddeley's working memory model: central executive (CE), phonological loop (PL), and visuo-spatial sketch pad (VSSP). The present experiment directly examined cognitive load using dual task methodology. The results were as follows: central executive (CE) suppression task achievement for the concept map AO group was higher than the key word AO group and control group. Comprehension and mental model construction for the concept map AO group were higher than the other groups. These results indicated that the superiority of concept map AO owing to CE load decrement occurred with comprehension and mental model construction in learning. Thus, the available resources produced by CE load reduction may have been invested for comprehension and mental model construction of learning contents.

An Improved One Round Authenticated Group Key Agreement (개선된 원 라운드 인증 그룹 키 합의 프로토콜)

  • Kim, Ho-Hee;Kim, Soon-Ja
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.23 no.1
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    • pp.3-10
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    • 2013
  • Several identity-based and authenticated key agreement protocols have been proposed. It remains at issue to design secure identity based and authenticated key agreement protocols. In this paper, we propose a one round authenticated group key agreement protocol which uses one more key pair as well as the public key and private key of typical IBE(Identity-Based Encryption) system. The proposed protocol modified Shi et al.'s protocol and He et al.'s protocol. The public and private keys and the signature process of our protocol are simpler than them of their protocols. Our protocol is secure and more efficient than their protocols in communication and computation costs.

Removal of Uranium from Uranium Plant Wastewater Using Zero-Valent Iron in an Ultrasonic Field

  • Li, Jing;Zhang, Libo;Peng, Jinhui;Hu, Jinming;Yang, Lifeng;Ma, Aiyuan;Xia, Hongying;Guo, Wenqian;Yu, Xia
    • Nuclear Engineering and Technology
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    • v.48 no.3
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    • pp.744-750
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    • 2016
  • Uranium removal from uranium plant wastewater using zero-valent iron in an ultrasonic field was investigated. Batch experiments designed by the response surface methodology (RSM) were conducted to study the effects of pH, ultrasonic reaction time, and dosage of zero-valent iron on uranium removal efficiency. From the experimental data obtained in this work, it was found that the ultrasonic method employing zero-valent iron powder effectively removes uranium from uranium plant wastewater with a uranium concentration of $2,772.23{\mu}g/L$. The pH ranges widely from 3 to 7 in the ultrasonic field, and the prediction model obtained by the RSM has good agreement with the experimental results.

The Phylotype of Thermus from the Rehai Geothermal Area, Tengchong, China

  • Guo, Chunlei;Wang, Tao;Zhu, Wei;Zhang, Donghua;Cui, Xiaolong;Xu, Lihua;Peng, Qian
    • Journal of Microbiology
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    • v.41 no.2
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    • pp.152-156
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    • 2003
  • Through enrichment on two nutrient agars, 57 Thermus isolates were recovered from 15 hot spring samples taken from the Rehai geothermal area, Tengchong, China. Unique growth characteristics were observed when the strains were transferred from YIM14 medium to Thermus medium. Phylogenetic analysis showed that the 16S rDNA sequences of the isolates and clones from the Rehai geothermal area farmed a monophyletic group on the phylogenetic tree. A secondary structure comparison showed that their 16S rRNAs have unique secondary structure characteristics.

Effects of Bedding Material Composition in Deep Litter Systems on Bedding Characteristics and Growth Performance of Limousin Calves

  • Meng, J.;Shi, F.H.;Meng, Qingxiang;Ren, L.P.;Zhou, Z.M.;Wu, H.;Zhao, L.P.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.1
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    • pp.143-150
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    • 2015
  • The objective of this study was to evaluate the effects of different litter mixture compositions on bedding system temperature, pH and volatile fatty acid and ammonia-N ($NH_3$-N) content, and the serum physico-chemical parameters and growth indices of calves. Thirty-two Limousin calves ($280{\pm}20kg$) were randomly assigned to four groups (n = 8 for each group) according to the bedding system used: i) control with soil only (CTR); ii) mixture with 50% paddy hulls (PH), 30% saw dusts (SD), 10% peat moss (PM) and 10% corn cobs (CC) (TRT1); iii) mixture with 15% PH, 15% SD, 10% PM, 40% CC, and 20% corn stover (CS) (TRT2); iv) mixture with 30% PH, 10% PM, 40% CC, and 20% CS (TRT3). The litter material combinations of different treatments were based on the cost of bedding system materials in China. The cost of four treatments from low to high: Control$NH_3$-N level (271.83 to 894.72 mg/kg) was lowest for TRT1 (p<0.0001) and highest for TRT2 (p<0.0001). The acetate, propionate and butyrate levels were highest for the control group (p<0.0001). In all the groups, the pH value (6.90 to 9.09) increased at the beginning and later remained stable at below 9.09. The temperature of deep litter increased at the first week and reached the maximum ($42.1^{\circ}C$) on day 38. 3,5,3'-Triiodothyronine ($T_3$) levels in the TRT1 group animals (p<0.0001) were lower than those in the control and TRT2 animals. 3,5,3',5'-Tetraiodothyronine ($T_4$) in the TRT1 group (p = 0.006) was lower than that in the other treatment groups. Cortisol (COR) in the control and TRT1 group was lower (p<0.0001) than that in the TRT2 and TRT3 groups. Corticosterone (CORt) in the control group was higher (p<0.0001) than that in the treatment groups. The findings indicate that the deep litter bedding systems provided better conditions for animal health and growth performance compared with the control system. Furthermore, the litter composition of TRT1 was found to be optimal among the three treatment groups.

Differences Between Breast Cancer Patients Younger and Older than 40 Years: Mammographic Findings

  • Zhao, Yu-Mei;Wang, Jian-Tao;Liu, Jing;Wang, Ju;Wang, Hong-Li;Liu, Pei-Fang
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.12
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    • pp.4929-4932
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    • 2014
  • Objective: To compare the mammogarphic appearance between breast cancer patients aged <40 and ${\geq}40$ years. Methods: Needle localization and biopsy of suspicious mammographic lesions identified 1,959 breast carcinomas in a single institution from Jun 2012 to Apr 2013. According to the age, we divided patients into two groups: <40 and ${\geq}40$ years old, and analyzed mammographic appearance separately. Results: Young patients had 44.2% foci with calcification, but old patients only had 39.4% (P<0.001). In younger group, the ratios of cases according to mass density were 41.8% or higher, 58.2% equivalent and lower. In older group, the ratios were 55.5 % and 44.5%, respectively. There were statistical differences between high density and others (P<0.05). The ratios of cases according to mass margin were 13.9% circumscribed and microlobulated, 86.1% indistinct and spiculated in the younger group, as compared to 6.5% and 93.5%, respectively, in the older group (P<0.05). Conclusions: Mammographic findings differ between young and old patients with breast cancer, for example regarding mass density, mass margin and microcalcification ratios.

A CHARACTERIZATION OF SOME PGL(2, q) BY MAXIMUM ELEMENT ORDERS

  • LI, JINBAO;SHI, WUJIE;YU, DAPENG
    • Bulletin of the Korean Mathematical Society
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    • v.52 no.6
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    • pp.2025-2034
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    • 2015
  • In this paper, we characterize some PGL(2, q) by their orders and maximum element orders. We also prove that PSL(2, p) with $p{\geqslant}3$ a prime can be determined by their orders and maximum element orders. Moreover, we show that, in general, if $q=p^n$ with p a prime and n > 1, PGL(2, q) can not be uniquely determined by their orders and maximum element orders. Several known results are generalized.

Secure Subgroup and Group Communication Service for TETRA System (TETRA 시스템을 위한 안전한 소그룹과 그룹통신 서비스)

  • 이수연;정진욱
    • Convergence Security Journal
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    • v.3 no.1
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    • pp.31-37
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    • 2003
  • This paper proposed a model supporting secure mechanism both group communication service and subgroup communication service of TETRA system that the standard developed by the technical committee Radio Equipment and Systems(RES) of the European Telecommunications Standards Institute(ETSI) provides a pure digital information technology for the transmission of speech and data. In each scheme, members in a subgroup maintains its subgroup key, which is not distributed, but computed by each member in the subgroup only with his own secret information and public values and secure subgroup members in a same subgroup can communication securely each other by using their subgroup key. Also, all members in group can share securely a group key. In communication services of TETRA system, this model supports mechanism for both group and subgroup communication are simultaneously needed.

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AtbZIP16 and AtbZIP68, two new members of GBFs, can interact with other G group bZIPs in Arabidopsis thaliana

  • Shen, Huaishun;Cao, Kaiming;Wang, Xiping
    • BMB Reports
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    • v.41 no.2
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    • pp.132-138
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    • 2008
  • AtbZIP16 and AtbZIP68 are two putative G group bZIP transcription factors in Arabidopsis thaliana, the other three members of G group bZIPs are GBF1-3 which can bind G-box. Members of G group have conservative protein structure: highly homological basic region and a proline-rich domain in the N-terminal region. Here, we report that AtbZIP16 and AtbZIP68 could bind cis elements with ACGT core, such as G-box, Hex, C-box and As-1, but with different binding affinities which from high to low were G-box > Hex > C-box > As-1; AtbZIP16 and AtbZIP68 could form homodimer and form heterodimer with other members of G group; N-terminal proline rich domain of AtbZIP16 had transactivation activity in yeast cells while that of AtbZIP68 did not; AtbZIP16 and AtbZIP68 GFP fusion protein localized in the nucleus of onion epidermal cells. These results indicated that AtbZIP16 and AtbZIP68 were two new members of GBFs. In Arabidopsis, AtbZIP16 and AtbZIP68 may also participate in light-responsive process in which GBF1-3 are involved.

In ovo feeding of creatine pyruvate alters energy metabolism in muscle of embryos and post-hatch broilers

  • Yang, Tong;Zhao, Minmeng;Li, Jiaolong;Zhang, Lin;Jiang, Yun;Zhou, Guanghong;Gao, Feng
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.6
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    • pp.834-841
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    • 2019
  • Objective: This study was conducted to investigate the effects of in ovo feeding (IOF) of creatine pyruvate (CrPyr) on the energy metabolism in thigh muscle of embryos and neonatal broilers. Methods: A total of 960 eggs were randomly assigned to three treatments: i) non-injected control group, ii) saline group injected with 0.6 mL of physiological saline (0.75%), and iii) CrPyr group injected with 0.6 mL of physiologi-cal saline (0.75%) containing 12 mg CrPyr/egg on 17.5 d of incubation. After hatching, 120 male chicks (close to the average body weight of the pooled group) in each group were randomly assigned to eight replications. The feeding experiment lasted 7 days. Results: The results showed that IOF of CrPyr increased glucose concentrations in the thigh muscle of broilers on 2 d after injection (p<0.05). Compared with the control and saline groups, the concentration of creatine in CrPyr group was increased on 2 d after injection and the day of hatch (p<0.05). Moreover, IOF of CrPyr increased the creatine kinase activity at hatch and increased the activities of hexokinase and pyruvate kinase on 2 d after injection and the day of hatch (p<0.05). Chicks in CrPyr group showed higher mRNA expressions of glucose transporter 3 (GLUT3) and GLUT8 on the day of hatch (p<0.05). Conclusion: These results demonstrated that IOF of CrPyr was beneficial to enhance muscle energy reserves of em-bryos and hatchlings.