• Title/Summary/Keyword: The Quaternary

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New Construction Method for Quaternary Aperiodic, Periodic, and Z-Complementary Sequence Sets

  • Zeng, Fanxin;Zeng, Xiaoping;Zhang, Zhenyu;Zeng, Xiangyong;Xuan, Guixin;Xiao, Lingna
    • Journal of Communications and Networks
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    • v.14 no.3
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    • pp.230-236
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    • 2012
  • Based on the known binary sequence sets and Gray mapping, a new method for constructing quaternary sequence sets is presented and the resulting sequence sets' properties are investigated. As three direct applications of the proposed method, when we choose the binary aperiodic, periodic, and Z-complementary sequence sets as the known binary sequence sets, the resultant quaternary sequence sets are the quaternary aperiodic, periodic, and Z-complementary sequence sets, respectively. In comparison with themethod proposed by Jang et al., the new method can cope with either both the aperiodic and periodic cases or both even and odd lengths of sub-sequences, whereas the former is only fit for the periodic case with even length of sub-sequences. As a consequence, by both our and Jang et al.'s methods, an arbitrary binary aperiodic, periodic, or Z-complementary sequence set can be transformed into a quaternary one no matter its length of sub-sequences is odd or even. Finally, a table on the existing quaternary periodic complementary sequence sets is given as well.

Preparation of Novel Quaternary Plastomers with Extremely Low Glass Transition Temperature

  • Kim, Jin Hoon;Kim, Jung Soo;Kim, Min Seong;Kim, Ki Bum;Yang, Hong Joo;Ha, Sung Chul;Chang, Young-Wook;Kim, Dong Hyun
    • Elastomers and Composites
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    • v.51 no.3
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    • pp.188-194
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    • 2016
  • In this study, novel quaternary plastomers consisting of ethylene, 1-hexene, high ${\alpha}$-olefin, and divinylbenzene were prepared using Zr metallocene catalyst, borate type cocatalyst, and tri-isobutylaluminium. The molar ratio changes of 1-hexene and high ${\alpha}$-olefin (1-octene, 1-decene, and 1-dodecene) had an effect on the properties of the quaternary plastomers. The structure of the quaternary plastomers was characterized using $^1H$ NMR. Molecular weight properties, crystallinity, and thermal properties of the plastomers were determined by GPC, WAXS, and DMA, respectively. Compared with the terpolymers prepared in our previous study, molecular weight and molecular weight distribution of the quaternary polymers were very similar, whereas glass transition temperature ($T_g$) was very low. Also, hardness and tensile properties of the quaternary plastomers were measured.

Review on the Usefulness and constraints of Paleotemperature Equations for the Late Quaternary Paleoclimatic Studies (제4기 후기 고기후복원을 위한 고온도 방정식의 유용성과 한계성에 관한 고찰)

  • 박용안
    • The Korean Journal of Quaternary Research
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    • v.10 no.1
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    • pp.19-26
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    • 1996
  • This review gives an information on the oxygen isotopic composition of car-bonate and utility of paleotemperature equations to reconstruct the paleoenvironment in the late Quaternary paleoclimatic studies. The introduc-tion of various paleotemperature equations is described with respect to the de-velopment and usefulness. In addition the calculation of paleotemperature in the paleoceanographic and paleoclimatic research is constrained to provide more precise and correct approach in the interpretation of paleotemperature.

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Stratigraphical Research of the Quaternary Deposits in the Korean Peninsula (韓半島 第四紀 地層의 層序的 考察)

  • Lee, Dong-Young
    • The Korean Journal of Quaternary Research
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    • v.1 no.1
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    • pp.3-20
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    • 1987
  • With regard to the Quaternary formations in the Korean Peninsula, very few studies have been done specially from a stratigraphic viewpoint. The alluvial sediments filling in the valleys have often been considered as the only formation of Quaternary age (more precisely of the Holocone) and so the Pleistocene was regarded as an erosional or nondepositional episode. This is apparently evident from a quick look at the general geological maps of the Peninsula, which show a lithological sequence of Mesozoic or Paleozoic substrata immediately overlain by Holocene alluvium. Likewise, the Pleistocene period was described in terms of unconformity in most local or regional stratigraphical successions of the Peninsula. Recently several different types of Quaternary formation, besides the so-called Holocene alluvium in the valley plain have been found around the Peninsula. They consist of coastal deposits, marine or fluviatile terrace deposits, ancient valley fill deposits or slope deposits. Some parts of the volcanic sediments in Jeju Is. are also known as the Quaternary sequence. Thus the Quaternary deposits in the Peninsula are far more developed than previously known to gelolgists. Moreover the importance of Quaternary research became recently apparent in Korea due to the shortage of raw materials and to the policy of an optimum land-use. Advanced constructions and land reclamation have required more precise engineering parameters of loose materials and an estimation of land stability. This does not imply only the engineering, or the structural properties of the loose material, but at the same time the basic study of the sediments from the stratigraphical and environmental viewpoints has been necessary. In this connection, Quaternary outcrops specially along the coastal fringe of the Peninsula have been mapped, profiled and sampled for sedimentological, clay-mineralogical and palaeomagnetic studies. All these results are compiled for the core of the Quaternary stratigraphy of the Peninsula.

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Design of a High Performance $8{\times}8$ Multiplier Using Current-Mode Quaternary Logic Technique (전류 모드 4치 논리 기술을 이용한 고성능 $8{\times}8$ 승산기 설계)

  • Kim, Jong-Soo;Kim, Jeong-Beom
    • Proceedings of the KIEE Conference
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    • 2003.11b
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    • pp.267-270
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    • 2003
  • This paper proposes high performance $8{\times}8$ multiplier using current-mode quaternary logic technique. The multiplier is functionally partitioned into the following major sections: partial product generator block(binary-quaternary logic conversion), current-mode quaternary logic full-adder block, quaternary-binary logic conversion block. The proposed multiplier has 4.5ns of propagation delay and 6.1mW of power consumption. Also, this multiplier can easily adapted to binary system by the encoder, the decoder. This circuit is simulated under 0.35um standard CMOS technology, 5uA unit current, and 3.3V supply voltage using Hspice.

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The Preparation of Quaternary Ammonium Polysulfone and its Permeation Behavior (II) - The Permeation Characteristics of Quaternary Ammonium Polysulfone Membranes - (Quaternary Ammonium Polysulfone막의 제조 및 투과 특성(II) - Quaternary Ammonium Polysulfone막의 투과특성 -)

  • 현진호;전종영;탁태문
    • Membrane Journal
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    • v.6 no.2
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    • pp.79-85
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    • 1996
  • This study is undertaken to investigate the effect of positive charge on the premeation characteristics of quaternary ammonium polysulfone (AMPS) membrane. AMPS membrane having a hydrophilic property was less fouled than PSf membrane. AMPS membrane had a positive charge and was thought to be able to expel charged solutes, such as basic dyes, proteins and amino acids, having same sign as the membrane surface.

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