• Title/Summary/Keyword: Block composition

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A Study on the Secure Double Pipe Hash Function (안전한 이중 파이프 해쉬함수에 관한 연구)

  • Kim, Hie-Do
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.6
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    • pp.201-208
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    • 2010
  • The classical iterated hash function is vulnerable to a multi-collision attack. Gauravaram et al. proposed 3C and 3C+ hash functions, in which an accumulation chain is added to usual Merkle-Damgard changing. Their goal is to design composition schemes resistant to generic attacks of Joux's type, but Joscak and Tuma have shown that 3C and 3C+ schemes are not better than Merkle-Damgard scheme in term of security against multi-collision attacks under some mild assumptions. In this dissertation, in order to increase security of 3C hash function, we proposed secure double pipe hash function which was effectively using XOR and XNOR operations per blocks of message. We seek to improve on the work of Lucks in a way. Proposed secure double pipe hash function takes resistance to multi-block collision, fixed point and pre-image attacks.

Effects of Numerical Modeling on Concrete Heterogeneity (콘크리트 비균질성에 대한 수치모델의 영향)

  • Rhee, In-Kyu;Kim, Woo
    • Journal of the Korea Concrete Institute
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    • v.18 no.2 s.92
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    • pp.189-198
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    • 2006
  • The composition of most engineering materials is heterogeneous at some degree. It is simply a question of scale at which the level of heterogeneity becomes apparent. In the case of cementitious granular materials such as concrete the heterogeneity appears at the mesoscale where it is comprised of aggregate particles, a hardened cement paste and voids. Since it is difficult to consider each separate particle in the topological description explicitly, numerical models of the meso-structure are normally confined to two-phase matrix particle composites in which only the larger inclusions are accounted for. 2-D and 3-D concrete blocks(Representative Volume Element, RVE) are used to simulating heterogeneous concrete meso-structures in the form of aggregates in the hardened mortar with nearly zero-thickness linear or planar interfaces. The numerical sensitivity of these meso-structures are Investigated with respect to the different morphologies of heterogeneity and the different level of coupling constant among fracture mode I, II and III. In addition, a numerically homogenized concrete block in 3-D using Hashin-Shtrikman variational bounds provides an evidence of the effective cracking paths which are quite different with those of heterogenous concrete block. However, their average force-displacement relationship show a pretty close match each other.

Fabrication and Thermophysical Properties of Al2O3-Based Multicomponent Composites by Sol-Gel Process (알루미나가 포함된 복합산화물의 제조와 열물성 특성평가)

  • Lim, Saet-Byeol;You, Hee-Jung;Hong, Tae-Whan;Jung, Mie-Won
    • Korean Journal of Materials Research
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    • v.20 no.9
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    • pp.472-477
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    • 2010
  • $Al_2O_3$ has received wide attention with established use as a catalyst and growing application in structural or functional ceramic materials. On the other hand, the boehmite (AlO(OH)) obtained by sol-gel process has exhibited a decrease in surface area during phase transformation due to a decline in surface active site at high temperature. In this work, $Al_2O_3$-CuO/ZnO (ACZ) and $Al_2O_3$-CuO/CeO (ACC) composite materials were synthesized with aluminum isopropoxide, copper (II) nitrate hemi (pentahydrate), and cerium (III) nitrate hexahydrate or zinc (II) nitrate hexahydrate. Moreover, the Span 80 as the template block copolymer was added to the ACZ/ACC composition to make nano size particles and to keep increasing the surface area. The ACZ/ACC synthesized powders were characterized by Thermogravimetry-Differential Thermal analysis (TG/DTA), X-ray Diffractometer (XRD), Field-Emmision Scanning Electron Microscope (FE-SEM), Bruner-Emmett-Teller (BET) surface analysis and thermal electrical conductivity (ZEM-2:M8/L). An enhancement of surface area with the addition to Span 80 surfactant was observed in the ACZ powders from 105 $m^2$/g to 142 $m^2$/g, and the ACC powders from 103 $m^2$/g to 140 $m^2$/g, respectively.

The Effect of Different Lupin Kernel Inclusion Levels on the Growth and Carcass Composition of Growing and Finishing Pigs

  • Kwak, B.O.;Kim, H.J.;Park, H.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.2
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    • pp.207-212
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    • 2000
  • Two experiments were conducted to investigate the effect of different lupin kernel levels on growth performance and carcass characteristics of growing and finishing pigs. In experiment 1, a total of 54 barrows and 54 growing gilts, with an average initial body weight of $24.7{\pm}0.38kg$, was used to determine the effect of different lupin kernel levels (0, 10% and 20%; Control, LK10 and LK20, respectively) in the diets on growth performance with a $3{\times}3$ randomized complete block design for 35 days. There were no significant differences in average daily gain (ADG), average daily feed intake (ADFI) and feed:gain among treatments. In experiment 2, a total of 54 barrows and 36 finishing gilts, with an average initial body weight of $63.0{\pm}0.56kg$, was used to determine the effect of different lupin kernel levels (0, 15% and 30%; Control, LK15 and LK30, respectively) in the diets on growth performance and carcass characteristics with a $3{\times}3$ randomized complete block design for 63 days. LK30 decreased ADG and ADFI compared with the Control and LK15 (p<0.05). However, LK30 tended to improve feed:gain compared with the Control and LK15. And LK15 did not differ from the Control in ADG, ADFI and feed:gain. With inclusion of lupin kernel in the finishing diet, backfat thickness increased (p<0.01) and carcass grade tended to be improved compared with the Control.

A Hierarchical Image Mosaicing using Camera and Object Parameters for Efficient Video Database Construction (효율적인 비디오 데이터베이스 구축을 위해 카메라와 객체 파라미터를 이용한 계층형 영상 모자이크)

  • 신성윤;이양원
    • Journal of Korea Multimedia Society
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    • v.5 no.2
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    • pp.167-175
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    • 2002
  • Image Mosaicing creates a new image by composing video frames or still images that are related, and performed by arrangement, composition and redundancy analysis of images. This paper proposes a hierarchical image mosaicing system using camera and object parameters far efficient video database construction. A tree-based image mosiacing has implemented for high-speed computation time and for construction of static and dynamic image mosaic. Camera parameters are measured by using least sum of squared difference and affine model. Dynamic object detection algorithm has proposed for extracting dynamic objects. For object extraction, difference image, macro block, region splitting and 4-split detection methods are proposed and used. Also, a dynamic positioning method is used for presenting dynamic objects and a blurring method is used for creating flexible mosaic image.

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Characterization of the Bovine FASN Gene Variation for Carcass and Beef Quality Traits in Hanwoo (소 FASN 유전자 변이의 연관불균형과 한우 도체형질에 미치는 영향)

  • Li, Song-Lan;Kim, Sang-Wook;Lee, Jung-Jae;Lee, Jun-Heon;Yoon, Du-Hak;Kim, Jong-Joo;Jeong, Young-Chul;Jeon, Soon-Hong;Choi, Jae-Won;Kim, Nae-Su;Kim, Kwan-Suk
    • Journal of Animal Science and Technology
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    • v.51 no.3
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    • pp.185-192
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    • 2009
  • Fatty acid synthase (FASN) is a multi-functional enzyme with a central role in the synthesis of long-chain fatty acid and has been considered as a positional candidate gene for BTA 19 quantitative trait loci (QTL) affecting milk-fat content and fatty acid composition. In this study, we sequenced the FASN gene in several cattle breeds including Hanwoo and imported beef cattle, and identified novel DNA polymorphisms and their linkage relationship in Hanwoo. We found a significant frequency difference of the FASN (AF285607) g.17924 A$\rightarrow$G polymorphism between Hanwoo (70%) and other breeds and this polymorphism has been known for an association with fatty acid composition in Angus. Furthermore, by direct DNA sequencing in 18 unrelated Hanwoo, we identified 27 SNPs including nine novel variations in the FASN gene. Among 27 SNPs identified in the FASN gene, four SNPs were further genotyped in 100 Hanwoo and 96 imported beef cattle, and analyzed for haplotype construction and association with beef quality traits. We performed haplotype block and linkage disequilibrium studies using four selected SNPs. Two different haplotype blocks (block A: g.10568 C$\rightarrow$T and g.11280 G$\rightarrow$ A; block B: g.13125 C$\rightarrow$T and g.17924 G$\rightarrow$A) were constructed and the block A in particular had a very high r2 (0.936), which indicated a nearly complete linkage disequilibrium existed between the g.10568 C$\rightarrow$T and g.11280 G$\rightarrow$A polymorphisms. A total of four major haplotypes (frequency > 0.05) were identified with the four polymorphisms including TATG (0.36), CGCG (0.31), CGTA (0.19) and TACG (0.06). Statistical association analysis revealed that the g.10568 C$\rightarrow$T and g.11280 G$\rightarrow$A polymorphisms in the FASN were significantly associated with meat color (P=0.004) and texture (P=0.0114). The g.13125 C$\rightarrow$T and g.17924 G$\rightarrow$A polymorphisms in the FASN were also significantly associated with back-fat thickness and quantity index (P=0.0179 and 0.0495, respectively). Our findings suggested that the FASN gene polymorphisms may be used for determining the (unsaturated) fatty acid contents and carcass trait in the Hanwoo beef.

Studies on the Phosphatic Fertilizer Application in Grassland II. Effects of phosphatic fertilizer application at the establishment and management of grassland on the botanical composition and mineral content of grasses (초지에 대한 인산질비료의 시용에 관한 연구 II. 초지조성 및 관리시에 인산질비료의 시용이 초지식생 및 목초의 무기물 함량에 미치는 영향)

  • Park, Geun Je;Lee, Pil Sang;Choe, Gi Jun;Hwang, Seok Jung
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.13 no.4
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    • pp.268-273
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    • 1993
  • With a purpose of finding out the effects of phosphatic fertilizer application at the grassland establishment and management on the botanical composition, mineral content of grasses and the chemical properties of soil. a field experiment was arranged with four treatments as a randomized complete block design and lasted from September, 1989 to October, 1991 in hilly area near Suweon. The results obtained are summarized as follows; 1. The botanical composition of grassland that phosphatic fertilizer was not applied was poor and the rate of legumes was increased with phosphatic fertilizer application and the effect of phosphatic fertilizer applications was obvious at the grassland management. 2. The mineral contents, N. P, Ca, Mg of grasses were increased with phosphatic fertilizer application but the K/Ca+Mg equivalent ratio of grasses was lowered and K content and Ca/P ratio tended not to be regular. 3. The available phosphorus contents and exchangable cation, Ca, Mg, contents of grassland soil were increased with phosphatic fertilizer applications but potasium contents tended not to be regular. 4. It was necessary to apply phosphatic fertilizer for the establishment and management of grassland. The botanical composition of grassland that phosphatic fertilizer was not applied at the establishment could be corrected into good stand with continuous phosphatic fertilizer applications at the management.

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The Market Effect of Additions or Deletions for KOSPI 200 Index : Comparison between Groups by Size and Market Condition (KOSPI 200지수종목의 변경에 따른 시장반응 : 규모와 시장요인에 따른 그룹간 비교분석)

  • Park, Young-S.;Lee, Jae-Hyun;Kim, Dae-Sik
    • The Korean Journal of Financial Management
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    • v.26 no.1
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    • pp.65-94
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    • 2009
  • The event of change in KOSPI 200 Index composition is one of the main subjects for the test of EMH. According to EMH, when a certain event is not related with firm's fundamental value, stock price should not change after the announcement of news. This hypothesis leads us to the conclusion of horizontal demand curve of stock. This logic was questioned by Shleifer(1986) and argued that downward sloping demand curve hypothesis was supported. But Harris and Gruel(1986) found a different empirical evidence that price reversal occurs in the long run, which is called price pressure hypothesis. They argued that short term price effect by large block trading (price pressure) is offset in the long run because these event is unrelated to fundamental value. Therefor, they argued that EMH can not be rejected in the long run. Until now, there are two empirical studies with Korean market data in this area. Using a data with same time period of $1996{\sim}1999$, Kweon and Park(2000) and Ahn and Park(2005) showed that stock price or beta is not significantly affected by change in index composition. This study retested this event expanding sample period from 1996 to 2006, and analyzed why this event was considered an uninformative events in the preceding studies. We analyzed a market impact by separating samples according to firm size and market condition. In case of newly enlisted firm, we found the evidence supporting price pressure hypothesis on average. However, we found the long run price effect in the sample of large firms under bearish markets. At the same time, we know that the number of samples under the category of large firms under bearish markets is relatively small, which drives the same result of supporting the hypothesis that change in index composition is a non-informative event on average. Also, the long run price effect of large size firms under bearish markets was supported by the analyses using trading volumes. On the other hand, in case of delisting from the index, we found the long run price effect but that was not supported by trading volume analyses.

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CHEMICAL COMPOSITION AND NUTRITIVE VALUE OF THE Gliricidia sepium PROVENANCES IN DRYLAND FARMING AREA IN BALI, INDONESIA

  • Sukanten, I.W.;Uchida, S.;Nitis, I.M.;Lana, K.;Putra, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.3
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    • pp.231-239
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    • 1995
  • Alley cropping field experiment has been carried out for 24 months in lime-stone based dryland farming area of southern Bali to study the chemical composition and nutritive value of 16 provenances of Gliricidia sepium The design was a completely randomized block: arrangement, consisted of 16 treatments (G. sepium provenances) and 6 blocks as replications with 12 plants per provenance. Of the 16 gliricidia provenances, six were from Mexico (M), four were from Guatemala (G), one each was from Colombia (C), Indonesia (I), Nicaragua (N), Panama (P), Costa Rica (R) and Venezuela (V). After 12 months establishment, the gliricidia were lopped at 150 cm height regularly 4 times a year, twice during the 4 months wet season and twice during the 8 months dry season. The highest ash, mineral, total soluble phenol, prussic acid and digestibility were in V1; the highest crude fiber component was in M39; the highest gross energy was in P13, while the highest organic matter was in M35. Based on the highest nutritive constituents, V1, C24 and G14 were ranked first, second and third respectively, while based on the lowest non-nutritive constituents C24, V1 and N14 were ranked first, second and third, respectively. The importance of such provenances as source of nutrients for the ruminant during the dry season were discussed.

Changes in Milk Production and Metabolic Parameters by Feeding Lactating Cows Based on Different Ratios of Corn Silage: Alfalfa Hay with Addition of Extruded Soybeans

  • Yana, Rong;Zhang, Ruizhong;Zhang, Xian;Jiang, Chao;Han, Jian-Guo;Zhang, Ying-Jun
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.6
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    • pp.800-809
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    • 2011
  • The objective of this study was to investigate the effects of different ratios of corn silage (CS): alfalfa hay (AH), and extruded soybeans (ESB) on milk yield, milk composition, blood metabolites, and fatty acids in milk fat and plasma. Ninety multiparous Holstein cows were arranged in a randomized block design experiment which lasted 14 weeks. Treatments were arranged as a $3{\times}3$ factorial with 0%, 5% or 10% ESB (dry matter basis) and three forage treatments: I) 30% CS, 10% AH and 10% Leymus chinense hay (LC); ii) 20% corn silage, 20% alfalfa hay and 10% LC; iii) 10% CS, 30% AH and 10% LC. Cows were allowed to consume a total mixed ration ad libitum. There was no change of dry matter intake when cows were fed the experimental diets. As more AH was added to the diets, milk yield, milk protein content and yield, and trans9, cis11-conjugated linoleic acids (CLA) concentrations in milk fat and plasma increased. When ESB were supplemented to the diets, milk yield, and trans9, cis11-CLA concentration in milk fat and plasma increased. When 10% ESB was added to the diet containing 30% AH the trans9, cis11-CLA content (1.46 g/100 g of total fatty acids) in milk was the highest among all treatments. These results suggests that AH could replace part of a CS diet and be a good forage source of diet for dairy cows to improve milk yield and milk composition. Meanwhile, ESB could be included in the diet with high AH to improve production performance of dairy cows.