• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.357-364
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• 1999

The purpose of this study is to analysis the grain distribution and compaction characteristics of structural backfill with reclaimed soil. Five(5) reclaimed soil samples which passed #200 sieve have been used in the test. The study showed that the maximum dry density and the bearing value rate turned out to be becoming smaller when the more the quantity passed #200 sieve, the smaller the soil grain. The maximum dry density value calculated from the compaction md relative density test showed wet method > compaction method > dry method. The correlation coefficient between Rc and Dr based on the grain distribution and the compaction characteristics showed that the maximum dry density value by the wet method is little higher than the compaction method and dry method.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.205-210
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• 2002

As the deposits of natural sands have slowly been depleted, it has resulted in an increase in manufactured fine aggregate (MFA). Standard specifications for fine aggregate for concrete contained in KS F 2558 permit a maximum of 7 percent finer than the No. 200 sieve (75${\mu}{\textrm}{m}$). Since the production process for MFA normally generates 10 to 20 percent of micro fines-which is defined as aggregates passing the No. 200 sieve (75${\mu}{\textrm}{m}$)-more than permitted by specifications, Excess fines must be removed by screening and/or washing operations. The amount of by-products will continue to grow as production increases with environmental discharge restrictions. This fundamental study focuses on experimental research for the adequacy of use of micro fines included in crushed aggregate using methylene blue test. Total of 63 types of sands from seven different rocks were tested. Based on the test results, the methylene blue test was turned out to be a good indicator of the quality of micro fines for concrete and a supplementary article and an amendment of the KS standard were recommended.

• Computers and Concrete
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• 제21권2호
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• pp.111-116
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• 2018

Establishment of test methods to assess the fresh properties of self-compacting concrete (SCC) are required to ensure the homogeneity in fresh and hardened states. This paper discusses the suitability of a simple test method for assessing the slump flow and stability of SCC by testing on self-compacting mortar (SCM) fraction. The proposed test method aims at investigating slump flow diameter test and sieve stability test of SCC by testing SCM fraction with a plunger penetration apparatus. A central composite modeling design was performed to evaluate the effects of water/cement ratio (W/C), superplasticizer dosage (SP) and powder marble content (MP) on slump flow diameter, stability and plunger penetration test of fresh SCC. The responses of the derived statistical models are slump flow (Sf), sieve stability (S) and plunger penetration (P). Relationships obtained in this study show acceptable correlations between plunger penetration test value and slump flow diameter test results and stability. It should note that the developed relationships are very useful to predict slump flow diameter and stability of studied SCC mixtures by carrying out a simple plunger penetration test on its mortar, which can save labour and time in laboratory experiments.

• 한국대기환경학회지
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• 제9권1호
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• pp.101-106
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• 1993

In order to separate the Freon-12 and air mixture$(CF_2Cl_2/Air=0.1/99.9 vol.%)$ by pressure swing adsorption (PSA), the breakthrough curve was experimentally observed in a fixed bed adsorption column. A single adsorber was packed with various adsorbents such as, the activated carbon(S-AC, W-AC) and the molecular sieve(MS-5A, MS-13X). The order of appearance of breakthrough curve is MS-5A > MS-13X > W-AC > S-AC. The activated carbon was found to be more effective adsorbent for separating Freon-12 from the mixture than the molecular sieve was. From the experimental data obtained by the separation of Freon-12 gas out of the air stream in the steady-state PSA process cycle, whose size is the same one of column used for the breakthrough curve observation, it has been confirmed that Freon-rich gas could be obtained from the purge step of PSA and Freon-free air could be obtained from the adsorption step of PSA cycle.

• 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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• 한국정보과학회언어공학연구회 2014년도 제26회 한글 및 한국어 정보처리 학술대회
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• pp.61-64
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• 2014

본 논문은 Stanford의 다 단계 시브(Multi-pass Sieve) 상호참조해결을 기반으로, 한국어에 적용한 한국어 상호참조해결(선행 연구)을 이용하여 한정 명사구에 대한 처리와 확장된 대명사 상호참조해결 방법을 제안한다. 지시 관형사와 명사가 결합하여 형성되는 한정 명사구는 일반 멘션(mention)의 특징과 대명사 속성을 한 번에 갖게 된다. 이렇게 되면, 한정 명사구는 모든 시브(sieve)에서 상호참조를 진행할 수 있게 된다. 따라서 이런 특징으로 한정 명사구를 어떤 관점(멘션 또는 대명사)에서 상호참조해결하는 것이 좋은지 보인다. 또한 이런 한정 명사구의 대명사 속성을 이용하기 위해 문법적 의미적 규칙을 적용할 것을 제안한다. 그 결과, 본 논문의 선행 연구인 한국어 상호참조해결에 비하여 CoNLL 값이 약 0.8%만큼 향상되어 61.45%를 측정하였다.

• Journal of Plant Biology
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• 제35권4호
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• pp.339-358
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• 1992

한국산 나자식물 6개과에서 대표적인 1종씩을 선정하여 수피의 특징을 형태 및 해부학적으로 조사하고 기재하였다. 수피를 인위적으로 조직단위로 간주할 경우 수피의 색, 두께, 내수피와 외수피의 두께, 확장조직의 유무 및 발달정도, 조피내 주피의 층우와 주피의 층수와 주피의 구성요소들의 두께, 2기 사부지역 각 구성요소들의 배열양상과 점유면적 비율 등은 종류에 따라 차이를 보였다. 또한 보강세포의 형태와 사세포의 사역 등도 앞으로 상세한 조사가 수행될 경우 비교형태학적 연구에 매우 가치있는 정보를 제공할 것으로 생각되었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권1호
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• pp.296-308
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• 2015

Advanced Encryption Standard (AES) is widely used for protecting wireless sensor network (WSN). At the Workshop on Cryptographic Hardware and Embedded Systems (CHES) 2012, G$\acute{e}$rard et al. proposed an optimized collision attack and break a practical implementation of AES. However, the attack needs at least 256 averaged power traces and has a high computational complexity because of its byte wise operation. In this paper, we propose a novel double sieve collision attack based on bitwise collision detection, and an improved version with an error-tolerant mechanism. Practical attacks are successfully conducted on a software implementation of AES in a low-power chip which can be used in wireless sensor node. Simulation results show that our attack needs 90% less time than the work published by G$\acute{e}$rard et al. to reach a success rate of 0.9.

• 한국통계학회:학술대회논문집
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• 한국통계학회 2005년도 추계 학술발표회 논문집
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• pp.159-165
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• 2005

Recently, as a result of the growing interest in modelling stationary processes with discrete marginal distributions, several models for integer valued time series have been proposed in the literature. One of theses models is the integer-valued autoregressive(INAR) models. However, when modelling with integer-valued autoregressive processes, there is not yet distributional properties of forecasts, since INAR process contain an accrued level of complexity in using the Steutal and Van Harn(1979) thinning operator 'o'. In this study, a manageable expression for the asymptotic mean square error of predicting more than one-step ahead from an estimated poisson INAR(1) model is derived. And, we present a bootstrap methods developed for the calculation of forecast interval limits of INAR(p) model. Extensive finite sample Monte Carlo experiments are carried out to compare the performance of the several bootstrap procedures.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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• pp.119-125
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• 2005

A method of predicting the tritium concentration in the air leaving an atmospheric detritiation dryer was modeled for designing a fixed bed dryer and preparing an advanced dryer control. In order to quantify the bed utilization and the dynamic capacity against an inlet humidity and a flow rate, a series of quantitative tests based on the break-through behavior were carried out in an isothermal fixed bed of synthetic zeolites such type as molecular sieve 4A, 5A, 13X and mordenite. The amount of water vapor breaking during the adsorption was estimated to give a breakthrough capacity at the various inlet flow rates and humidity conditions. The molecular sieve 13X exhibited a better adsorption performance at a given bed height.

• 미생물학회지
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• 제27권2호
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• pp.117-123
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• 1989

Radioactive NBZ arginyl diazomethane으로 액포를 표지 한 뒤에ㅣ 액포내의 단백질과 세포막 겉에 존재하는 단백질을 각각 저농도 완충용액과 높은 농도의 염용액으로 제거시켰다. 액포막 단백질을 Triton X-100으로 녹인 후, molecular sieve column chromatography와 ion exchange column chromatography를 사용하여 anginine transporter를 분리하였다.