• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.435-436
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• 2008

This paper presents a dual band frequency synthesizer for GSM and Wideband CDMA which is designed in a standard 0.13um CMOS 1P6M process. The shared components include phase frequency detector (PFD), charge pump (CP), loop filter, integer frequency divider(128/129 DMP, 4bit PC, 3bit SC) and Low noise Ring-VCO. A high-speed low power dual modulus prescaler is proposed to operate up to 2.1GHz at 3.3V supply voltage with 2mW power consumption by simulation. The simulated phase noise of VCO is -101dBc/Hz at 200kHz offset frequency from 1.9GHz.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.111-111
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• 2011

유기박막트랜지스터는 각 박막계면의 접촉성에 따라 그 성능이 좌우 된다는 것은 널리 알려진 사실이다. 이 때문에 계면간의 접촉성 및 결함을 최소화 하고 효율적인 패턴 형성을 위해 자기조립단분자막의 이용이 최근에 많이 시도되고 있다. 고품질 자기조립단분자막의 제작을 위해 RCA 세척을 통해 웨이퍼 표면에 OH기를 도입 보다 완벽한 단분자막의 형성을 촉진 하였으며 패턴제작은수분이엄격이조절된환경에서 alkyilsilane과 aminosilane 자기조립단분자막을 각각 ${\mu}CP$과 용액공정을 통해 시도되었다. 이 과정에서 물리적 흡착이나 OH기 부족으로 생성된 결함을 보안하기 위하여 SC1용액을 사용 단순 물리흡착된 자기조립단분자 물질의 제거와 다시 OH기 도입 용액공정을 통해 자기조립단분자막 형성을 반복적으로 실시하였다. 그 결과 자기조립단분자막의 결함이 최소화 되었고 자기조립단분자막의 질에 따라 유기전극재료 증착 시 선택적인 성장 과 형성된 유기전극재료 층의 형상이 다르게 관찰 되었다. 이런 반복적인 용액공정을 통해 결함이 최소화된 고품질 자기조립단분자막은 박막계면 간 옴성접촉을 형성하여 유기박막트랜지스터 제작 시 성능 향상이 기대되어진다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.5
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• pp.1638-1653
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• 2014

A sequential optimization algorithm (SOA) for resource allocation in a cyclic-prefixed single-carrier cognitive relay system is proposed in this study. Both subcarrier pairing (SP) and power allocation are performed subject to a primary user interference constraint to minimize the mean squared error of frequency-domain equalization at the secondary destination receiver. Under uniform power allocation at the secondary source and optimal power allocation at the secondary relay, the ordered SP is proven to be asymptotically optimal in maximizing the matched filter bound on the signal-to-interference-plus-noise ratio. SOA implements the ordered SP before power allocation optimization by decoupling the ordered SP from the power allocation. Simulation results show that SOA can optimize resource allocation efficiently by significantly reducing complexity.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1763-1769
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• 2003

Two experiments were conducted to examine the production and quality of cassava hay and its utilization in diets for dairy cows. In experiment I, a $2{\times}2$ Factorial arrangement in a randomized complete block design with 4 replications was carried out to determine the effects of different initial (IC) and subsequent cutting (SC) on yield and composition of cassava plant. The results revealed that cassava could produce from 4 to 7 tonne of DM and 1.2 to 1.6 tonne of CP for the first six months after planting. CP content in cassava plant ranged from 20.8 to 28.5% and was affected by different SC regimes. Condensed tannin in cassava foliage ranged from 4.9 to 5.5%. Initial cutting at 2 months with subsequent cutting at 2 month intervals was the optimal to obtain high dry matter and protein yield. In the second experiment, five crossbred Holstein-Friesian cows in mid lactation with an initial live-weight of 505${\pm}6.1kg$ and average milk yield of 10.78${\pm}1.2kg/d$ were randomly assigned in a $5{\times}5$ Latin square design to study the effects of 2 levels of CH (1 and 2 kg/hd/d) and concentrate (1 to 2 kg of milk and 1 to 3 kg of milk) on milk yield and milk composition. The results showed that cassava hay increased rumen $NH_3-N$ and milk urea nitrogen (MUN) (p<0.05). Cassava hay tended to increase milk production and 4% FCM. Milk protein increased in cows fed cassava hay (p<0.05). Moreover, cassava hay could reduce concentrate levels in dairy rations thus resulting in increased economic returns. Cassava hay can be a good source of forage to reduce concentrate supplementation and improve milk quality.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.1A
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• pp.134-141
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• 2007

This paper presents a frequency synthesizer(FS) for 5.2GHz/2.4GHz dual band wireless applications which is designed in a standard $0.18{\mu}m$ CMOS1P6M process. The 2.4GHz frequency is obtained from the 5.2GHz output frequency of Voltage Controlled Oscillator (VCO) by using the Switched Capacitor (SC) and the divider-by-2. Power dissipations of the proposed FS and VCO are 25mW and 3.6mW, respectively. The tuning range of VCO is 700MHz and the locking time is $4{\mu}s$. The simulated phase noise of PLL is -101.36dBc/Hz at 200kHz offset frequency from 5.0GHz with SCA circuit on.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.2
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• pp.72-77
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• 2009

In this paper, a 3.2Gb/s clock and data recovery (CDR) circuit for a high-speed serial data communication without the reference clock is described This CDR circuit consists of 5 parts as Phase and frequency detector(PD and FD), multi-phase Voltage Controlled-Oscillator(VCO), Charge-pumps (CP) and external Loop-Filter(KF). It is adapted the PD and FD, which incorporates a half-rate bang-bang type oversampling PD and a half-rate FD that can improve pull-in range. The VCO consists of four fully differential delay cells with rail-to-rail current bias scheme that can increase the tuning range and tuning linearity. Each delay cell has output buffers as a full-swing generator and a duty-cycle mismatch compensation. This materialized CDR can achieve wide pull-in range without an extra reference clock and it can be also reduced chip area and power consumption effectively because there is no additional Phase Locked- Loop(PLL) for generating reference clock. The CDR circuit was designed for fabrication using 0.18um 1P6M CMOS process and total chip area excepted LF is $1{\times}1mm^2$. The pk-pk jitter of recovered clock is 26ps at 3.2Gb/s input data rate and total power consumes 63mW from 1.8V supply voltage according to simulation results. According to test result, the pk-pk jitter of recovered clock is 55ps at the same input data-rate and the reliable range of input data-rate is about from 2.4Gb/s to 3.4Gb/s.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.3
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• pp.278-286
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• 2019

Sesbania, an annual herb, is known for its high forage value and salt tolerance. It has merits as a forage crop that is adaptable to reclaimed land in the Republic of Korea. Therefore, we collected Sesbania genetic resources from the Republic of Korea and other countries, and conducted experiments to evaluate their potential as a forage crop in Korean climate and soil conditions. In the preliminary experiments, 15 genetic resources which were able to set seeds in Korean environment were selected out of a total of 46 collected genetic resources. Among 15 genetic resources, SL13 was the tallest and it was followed by that of SC04, SR01 and SE07. The accessions with the earliest flowering started flowering 101 days after sowing and set seed in early August. Fifteen accessions were evaluated for their salt tolerance at germination stage based on germination rate and growth of germinated seedlings at 0 mM, 150 mM and 300 mM NaCl concentrations. Five genetic resources like SC04, SL13, SS20, SS24 and SR01 were selected to be tolerant to NaCl treatment. Forage value was evaluated based on crude protein, acid detergent fiber, neutral detergent fiber and in vitro dry matter digestibility. The forage value of leaves was significantly higher than that of stems, and the forage value of the stem was slightly better than that of rice straw. The forage value of leaves of all the genetic resources was higher than grade 1 by the American Forage and Grassland Council grade. Among five selected genetic resources, the relative feed value of SC04 was the highest and it was followed by that of SS20, SL13, SS24 and SR01.

• Language and Information
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• v.6 no.2
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• pp.1-14
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• 2002

This paper discusses so called the non-DP subject constructions in English. In general, a subject is a DP that bears Nominative case and that occupies 〔Spec, IP〕. However, in some examples under investigation, it looks as if non-DP categories such as Prepositional Phrases(PP), Adjectival Phrases(AP), Adverbial Phrases (AdvP), Small Clauses (PreP or SC), and VP occupy the canonical subject position, 〔Spec, IP〕. Under the framework of Chomsky's (1993, 1995) along with his previous works (Chomsky 1981, 1986), the Case Checking mechanism undoubtedly assumes that only DPs can have Case Therefore, the Case Checking/Agree mechanism is stated such that the strong uninterpretable feature, in this case Case feature (D or NP) feature must be checked off in a certain manner. Therefore, any phrasal categories other than DPs are not included in the considerations. Nonetheless, there are many instances of non-DP categories in English that occupy the seemingly canonical subject position, 〔spec, IP〕. In this paper, it is proposed that the actual position of these non-DP subjects in English is not in Spec of IP. Rather, they occupy 〔Spec, TopP〕 under CP in the sense of Lasnik & Stowell (1991), Rizzi (1997), and Haegeman & Gueron (1999). In its effect, therefore, this paper extends the idea of Stowell (1981) who argues that the clausal subjects in English is not in 〔Spec, IP〕, but in 〔Spec, TopP〕. We further argue that Stowell's version of Case Resistance Principle must be extended in order to accomodate many more occurrences of so called non-DP subjects.

• Journal of Satellite, Information and Communications
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• v.6 no.1
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• pp.86-96
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• 2011

In this paper we propose a Pre-rake system applied with a frequency domain equalizer in TDD/CDMA multi-code transmission. The Pre-rake system has been well known technique in TDD/CDMA to make a receiver simple. However, it still has residual losses of path diversity and signal to noise ratio (SNR). However, gathering all the residual paths demands an additional hardware such as a rake combiner at the receiver. For the reason Pre/Post-rake system has already been proposed at up/downlink correlated channel conditionunder the assumption of noisier channel. There is a trade-off between the first purpose of Pre-rake that makes hardware simple at the receiver and the performance improvement. From the point the frequency domain equalizer (FDE) can be considered in Pre/Post-rake to supply the receiver with the flexible equalizing methods with rather reduced complexity compared with time domain rake combiner or equalizers. Pre-rake itself increases the number of multipath, which results from the convolution of Pre-rake filter and wireless channel, and FDE must be well matched to Pre/Post-rake, while it considers the relationship of hardware complexity and the performance. In this paper, the Pre-rake/Post-FDE system is introduced at TDD/CDMA multi-code transmission. In addition, the cyclic prefix reduction method in the proposed system is introduced, and the theoretical analysis to the proposed system is given by assuming Gaussian approximation, and finally the numerical simulation results are provided.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.91-95
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• 2009

To examine physico-chemical properties of the polysaccharide extracted from liquid-cultured mycelia of Schizophyllum commune, each the polysaccharide was extracted with hot water treatment and then fractionated with ethanol, alkaline solution and ultrafiltration. And we determined carbohydrate contents, composition of amino acids, infra-red spectrum and viscosity. Carbohydrate contents of polysaccharide treated with ethanol and ultrafiltration were 72.0% and 62.3%, and proteins content were 15.3% and 32.0% respectively. The carbohydrate consisted of four monosaccharides and the protein contained 16 amino acids. The polysaccharide obtained from ultrafiltration was shown an absorption band characteristic of the ${\beta}$-glycosidic linkage by infra red spectra. These results suggest that the polysaccharide extracted from Schizophyllum commune showed the characteristics of proteinbounded polysaccharide, and it was ${\beta}$-glycosidic linkage with strong viscosity.