• 제목/요약/키워드: General additive

검색결과 238건 처리시간 0.027초

DSR을 이용한 온도변화에 따른 중온화 첨가제의 다짐특성 연구 (Study of WMA Additive's Compaction Characteristics in Terms of Temperature Change by Using DSR)

  • 황성도;이상재;조동우;이석근
    • 한국도로학회논문집
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    • 제15권4호
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    • pp.11-20
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    • 2013
  • PURPOSES : This study is to develop a method to evaluate the compaction effects of asphalt binders using WMA additives and compare their compaction effects on two types of WMA additives, two types of testing temperatures, and three types of asphalt film thicknesses. METHODS : This study is based on laboratory experiments and rheological analysis of the experimental results. Testing materials are aggregate disks, asphalt, and WMA additives. The main testing method is the stress sweep test by using dynamic shear rheometer (DSR). In addition, the testing parameters obtained from the stress sweep results to evaluate lubrication effects are complex modulus and LVE-Limit. RESULTS : At both the first compaction condition ($110^{\circ}C$, 0.3mm) and second compaction condition ($80^{\circ}C$, 0.2mm) assumed, LEADCAP showed better compaction effects than Sasobit. CONCLUSIONS : The temperature $30^{\circ}C$ lower than general compaction temperatures can provide a better sensitivity for the evaluation of compaction effects. If a testing temperature and film thickness are grouped for the proper compaction conditions in the testing results, the compaction performance of each WMA additive can be more clearly discriminated in the grouped testing results matched with the grouped conditions.

첨가제에 의한 0.05PAN-0.95PZT계 세라믹의 압전특성에 관한 연구 (A study on the piezoelectric characteristics of 0.05PAN-0.95PZT ceramics with additive)

  • 김현철;허석현;김진섭;임인호;배선기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.419-422
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    • 2000
  • This paper was to measure the structure, piezoelectric properties of 0.05Pb($A1_{0.5}$$Nb_{0.5}$)-0.95Pb($Zr_{0.52}$$Ti_{0.48}$)$O_3$ ceramics dopped with additive after creating the specimens with a general method. It is shown that X-ray diffraction pattern variation of lines (200) have tendency to move in simple peak by addition of additive. According to the increase of $Cr_2$$O_3$, tetragonality hardly have variation, according to the increase of $Fe_2$$O_3$, tetragonality decreased on the whole. According to dopping with $Cr_2$$O_3$ and $Fe_2$$O_3$, electromechanical factor(kp) largely increased, in case of sintering at $1200^{\circ}C$ kp was maximum value of 40.04[%] at $Cr_2$$O_3$ 0.3wt%, and maximum value of kp 42.9 [%] at $Fe_2$$O_3$, 0.9wt%. In case of sintering at 120$0^{\circ}C$, mechanical duality factor(Qm) was maximum value of Qm 268.8 at $Cr_2$$O_3$, 0.9 wt%.

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STABILITY OF A MIXED QUADRATIC AND ADDITIVE FUNCTIONAL EQUATION IN QUASI-BANACH SPACES

  • Najati, Abbas;Moradlou, Fridoun
    • Journal of applied mathematics & informatics
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    • 제27권5_6호
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    • pp.1177-1194
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    • 2009
  • In this paper we establish the general solution of the functional equation f(2x+y)+f(x-2y)=2f(x+y)+2f(x-y)+f(-x)+f(-y) and investigate the Hyers-Ulam-Rassias stability of this equation in quasi-Banach spaces. The concept of Hyers-Ulam-Rassias stability originated from Th. M. Rassias' stability theorem that appeared in his paper: On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc. 72 (1978), 297-300.

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Comparison of tree-based ensemble models for regression

  • Park, Sangho;Kim, Chanmin
    • Communications for Statistical Applications and Methods
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    • 제29권5호
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    • pp.561-589
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    • 2022
  • When multiple classifications and regression trees are combined, tree-based ensemble models, such as random forest (RF) and Bayesian additive regression trees (BART), are produced. We compare the model structures and performances of various ensemble models for regression settings in this study. RF learns bootstrapped samples and selects a splitting variable from predictors gathered at each node. The BART model is specified as the sum of trees and is calculated using the Bayesian backfitting algorithm. Throughout the extensive simulation studies, the strengths and drawbacks of the two methods in the presence of missing data, high-dimensional data, or highly correlated data are investigated. In the presence of missing data, BART performs well in general, whereas RF provides adequate coverage. The BART outperforms in high dimensional, highly correlated data. However, in all of the scenarios considered, the RF has a shorter computation time. The performance of the two methods is also compared using two real data sets that represent the aforementioned situations, and the same conclusion is reached.

천연 염지제를 첨가한 오리훈제의 항산화 활성과 영양적 특성 (Antioxidant activities and nutritional characteristics of smoked duck marinated in natural curing agent)

  • 박연옥
    • Journal of Nutrition and Health
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    • 제47권6호
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    • pp.484-488
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    • 2014
  • Purpose: This study investigated the question of whether the addition of natural ingredients (pear fermented solution, celery powder, vitamin C) in curing agents may influence antioxidant activities and nutritional characteristics of smoked duck. Methods: Smoked duck samples with general or natural curing agent containing three additive ingredients were examined to determine total polyphenol contents, antioxidant activities, pH, TBARS, and food additives residue (nitrite ion, antioxidant, sodium glutamate). Results: Smoked duck with natural curing agent showed a higher level of total polyphenol content and antioxidant activities than smoked duck using general curing agent (p < 0.05). The pH and TBARS of smoked duck were significantly decreased by the addition of natural curing ingredients compared to those of smoked duck using general curing agent (p < 0.05). The residues of food additives were not detected in smoked duck using natural curing agent. Conclusion: Findings suggest that the addition of pear fermented solution, celery powder, and vitamin C in natural duck curing agent may improve the antioxidant activities and nutritional characteristics of smoked duck and provides health benefits.

서울시의 대기오염과 일별 사망자 수의 관련성에 대한 시계열적 연구 (Air Pollution and Daily Modality in Seoul)

  • 조수헌;권호장
    • Journal of Preventive Medicine and Public Health
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    • 제32권2호
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    • pp.191-199
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    • 1999
  • 대기오염이 인체에 미치는 영향을 정량적으로 분석하기 위하여 1991년부터 1995년까지의 서울시 사망자료와 대기오염 자료를 general additive Poisson model 을 사용하여 분석하였다. 우리 나라에서도 외국의 연구 결과와 마찬가지로 대기 오염 물질의 증가가 사망자 수의 증가에 유의하게 영향을 미치는 것으로 평가되었다. 특히 본 연구에서 나타난 특성은 일반적으로 많이 알려진 분진에 의한 영향 보다는 오존에 의한 영향이 두드러진다는 것이다. 오존은 100ppb가 증가할 때 마다 사망자 수를 3-10% 증가시키는 것으로 평가되었다. 즉 오존주의보가 발령될 때마다 서울시에서는 많게는 평소보다 10%정도의 추가적인 사망이 발생하는 것으로 추정된다. 이러한 연구결과는 우리 나라의 대기오염 양상이 분진과 $SO_2$ 중심의 '런던스모그'형에서 오존과 $NO_2$ 등에 의한 광화학적 스모그로 바뀌고 있는 사실을 감안할 때 시사하는 바가 매우 크다고 할 수 있다. 따라서 앞으로는 병원입원율, 또는 응급실 내원환자수에 대한 오존의 영향을 평가할 수 있는 연구들이 이어져야 할 것으로 생각되며, 더불어 오존 오염을 감소시킬 수 있는 구체적인 정책들이 시급히 시행되어야 할 것으로 생각된다.

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ON A SYMMETRIC FUNCTIONAL EQUATION

  • Chung, Jae-Young
    • 호남수학학술지
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    • 제34권3호
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    • pp.375-379
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    • 2012
  • We find a general solution $f:G{\rightarrow}G$ of the symmetric functional equation $$x+f(y+f(x))=y+f(x+f(y)),\;f(0)=0$$ where G is a 2-divisible abelian group. We also prove that there exists no measurable solution $f:\mathbb{R}{\rightarrow}\mathbb{R}$ of the equation. We also find the continuous solutions $f:\mathbb{C}{\rightarrow}\mathbb{C}$ of the equation.

A Modified Soft Output Viterbi Algorithm for Quantized Channel Outputs

  • Lee Ho Kyoung;Lee Kyoung Ho
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 학술대회지
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    • pp.663-666
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    • 2004
  • In this paper, a modified-SOYA (soft output viterbi algorithm) of turbo codes is proposed for quantized channel receiver filter outputs. We derive optimum branch values for the Viterbi algorithm. Here we assume that received filter outputs are quantized and the channel is additive white Gaussian noise. The optimum non-uniform quantizer is used to quantize channel receiver filter outputs. To compare the BER (bit error rate) performance we perform simulations for the modified SOYA algorithm and the general SOYA

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잡음 ARMA 프로세스의 적응 매개변수추정 (Adaptive Parameter Estimation for Noisy ARMA Process)

  • 김석주;이기철;박종근
    • 대한전기학회논문지
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    • 제39권4호
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    • pp.380-385
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    • 1990
  • This Paper presents a general algorithm for the parameter estimation of an antoregressive moving average process observed in additive white noise. The algorithm is based on the Gauss-Newton recursive prediction error method. For the parameter estimation, the output measurement is modelled as an innovation process using the spectral factorization, so that noise free RPE ARMA estimation can be used. Using apriori known properties leads to algorithm with smaller computation and better accuracy be the parsimony principle. Computer simulation examples show the effectiveness of the proposed algorithm.