• Membrane Journal
• /
• v.6 no.2
• /
• pp.79-85
• /
• 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.

• Proceedings of the KIEE Conference
• /
• 2003.11b
• /
• pp.267-270
• /
• 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.

• The Korean Journal of Quaternary Research
• /
• v.14 no.2
• /
• pp.125-135
• /
• 2000

The late Quaternary stratigraphy and basal unconformity (nonconformity) of the intertidal deposits (upper tidal flat) in the Banweol tidal basin in the Kyunggi Bay, west coast of Korea has been investigated and established. The Unit I (middle to late Holocene upper intertidal deposit) and Unit II (pre-Holocene fluvial to alluvial deposit) in descending order are classified and interpreted. The basement rocks of the Banweol tidal basin is dominantly preCambrian metamorphic rocks on which Unit II is overlying unconformably. In short, the late Quaternary stratigraphy and unconformity of the Banweol tidal flat deposits are established and interpreted in terms of sedimentology and sea-level fluctuation history during late Quaternary.

• The Korean Journal of Quaternary Research
• /
• v.19 no.1
• /
• pp.27-40
• /
• 2005

Researches onmarine terrace in Korea have been drastically progressed during the last two decades.main themes of researches include vertical and horizontal distribution of paleo-shoreline, sedimentary facies ofmarine terrace deposits, OSL dating of terrace deposits and estimation of uplift rate. At present, it is noted thatmarine terraces distributed at the same altitude do not always show the same sedimentary facies, nor have the same ages.marine terraces are generally divided into five terrace systems, of which ages increase in ascending order. There are some arguments about discrimination between 2nd and 3rd terrace systems and their age. The core discrepancy lies on the question of whether the level of the last interglacial terrace is on the level of about 20m or on the 30~35m(~40m) in altitude. The uplift rate based on the paleoshoreline distribution ranges between 0.10 and 0.20m/ka.

• Polymer(Korea)
• /
• v.39 no.1
• /
• pp.122-129
• /
• 2015

Recently, the development of a new class of anti-fouling paint resin which has excellent anti-fouling performance and no persistence in the marine ecology is necessary. In this study, we first polymerized polyurethanes (PUs) as the other type of matrix which have carboxylic acid groups by using poly(ethylene glycol) (PEG), 4,4'-diphenylmethane diisocyanate (MDI), and 2,2'-bis(hydroxyl methyl)-propionic acid (DMPA). And next, we synthesized final resins having quaternary ammonium salts on pendant acid groups of PUs. After synthesis, the physical self-polishing property of resin by the measurement of reduced thickness in sea water was tested. The mechanical property of antifouling paint resin was good when the molecular weight of PEG was 600 or less. It was confirmed that the adhesion of PU resin was deteriorated when the content of quaternary ammonium salt was incorporated over specific value.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.40 no.3
• /
• pp.152-162
• /
• 2003

In this paper, Binary to Quaternary Converter(BQC), Quaternary to Binary Converter(QBC) and Quaternary inverter circuit, which is the basic logic gate, have been proposed based on voltage mode. The BQC converts the two bit input binary signals to one digit quaternary output signal. The QBC converts the one digit quaternary input signal to two bit binary output signals. And two circuits consist of Down-literal circuit(DLC) and combinational logic block(CLC). In the implementation of quaternary inverter circuit, DLC is used for reference voltage generation and control signal, only switch part is implemented with conventional MOS transistors. The proposed circuits are simulated in 0.35 ${\mu}{\textrm}{m}$ N-well doubly-poly four-metal CMOS technology with a single +3V supply voltage. Simulation results of these circuit show 250MHz sampling rate, 0.6mW power consumption and maintain output voltage level in 0.1V.

• Journal of Advanced Navigation Technology
• /
• v.14 no.5
• /
• pp.710-717
• /
• 2010

Even though there are 256 possible 1-qudit(1-variable quantum digit) functions in quaternary logic, the most useful functions are 4!=24 ones capable of representing in QGFSOP expressions by possible permuting of 0,1,2, and 3. In this paper, we propose a permutational literal(PL) representation and a QPL(Quaternary PL) gate which use the operands of a multiplicand A and an augend D in $Ax^C$+D(GF4) operation as a control variable of multi-cascaded PLs. And we also present new PL synthesis algorithms to synthesize QGFSOP expressed 24 (1-qudit) functions by applying three PL operators as ab(mutual permutation), + D(addition), and XA (multiplication). Finally architectures, circuits, and a CMOS implementation to realize proposed PL synthesis algorithms for $Ax^C$+D(GF4) functions are presented.

• Proceedings of the Korean Quaternary Association Conference
• /
• 2004.06a
• /
• pp.33-36
• /
• 2004

• Proceedings of the Korean Quaternary Association Conference
• /
• 2004.06a
• /
• pp.30-32
• /
• 2004

• Proceedings of the Korean Quaternary Association Conference
• /
• 2004.06a
• /
• pp.26-28
• /
• 2004