• 한국수산과학회지
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• 제38권4호
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• pp.265-275
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• 2005

A prerequisite for deriving the abundance estimates from acoustic surveys for commercially important fish species is the identification of target strength measurements for selected fish species. In relation to these needs, the goal of this study was to construct a data bank for converting the acoustic measurements of target strength to biological estimates of fish length and to simultaneously obtain the target strength-fish length relationship. Laboratory measurements of target strength on 15 commercially important fish species were carried out at five frequencies of 50, 70, 75, 120 and 200 kHz by single and split beam methods under the controlled conditions of the fresh and the sea water tanks with the 389 samples of dead and live fishes. The target strength pattern on individual fish of each species was measured as a function of tilt angle, ranging from $-45^{\circ}$ (head down aspect) to $+45^{\circ}$ (head up aspect) in $0.2^{\circ}$ intervals, and the averaged target strength was estimated by assuming the tilt angle distribution as N $(-5.0^{\circ},\;15.0^{\circ})$. The TS to fish length relationship for each species was independently derived by a least-squares fitting procedure. Also, a linear regression analysis for all species was performed to reduce the data to a set of empirical equations showing the variation of target strength to a fish length, wavelength and fish species. For four of the frequencies (50, 75, 120 and 200 kHz), an empirical model for fish target strength (TS, dB) averaged over the dorsal sapect of 602 fishes of 10 species and which spans the fish length (L, m) to wavelength (\Lambda,\;m)$ ratio between 5 and 73 was derived: $TS=19.44\;Log(L)+0.56\;Log(\Lambda)-30.9,\;(r^2=0.53)$.

• 말소리와 음성과학
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• 제5권2호
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• pp.11-22
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• 2013

The purpose of this study was to identify the relationship between the strength of the tongue/lip strength and speech production for dysarthric adults with cerebral palsy. The maximal tongue and lip strengths of 22 normal adults, 27 dysarthric adults (10 adults with mild dysarthria, 10 adults with moderate dysarthria, and 7 adults with severe dysarthria) were measured with Iowa Oral Performance Instrument (IOPI). The percentage of correct consonants (PCC) and speech intelligibility were calculated from the words and sentences spoken by the subjects. The results of the study are as follows: First, both the maximal tongue and the maximal lip strength differed significantly between the control group and the group with dysarthria. While the group with mild dysarthria did not show meaningful difference in maximal tongue and lip strengths from the control group, the group with moderate and severe dysarthria showed significantly weaker tongue and lip strength than the control group and the group with mild dysarthria. Second, the current study suggests the existence of a significant correlation between the maximal tongue and lip strength and the PCC and speech intelligibility within all subjects with dysarthria. These findings can serve as an effective foundation to diagnose dysarthria quickly and accurately. The results of this study also indicate that in addition to the maximal tongue strength, the maximal lip strength can prove to be an important index in predicting the speech intelligibility of dysarthric adults with cerebral palsy.

• The Journal of Korean Physical Therapy
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• 제23권4호
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• pp.15-22
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• 2011

Purpose: The purpose of this study was to investigate the relationship between hip abductor muscle strength and lumbar instability in patients with chronic low back pain. Methods: Fifty-two female patients were recruited for this study. The patients' history was recorded and was used to determine the general characteristics of the female complaints. The women were additionally examined to determine whether the level of pain was characteristic of patients with chronic lumbar instability. The following tests were also carried out in the subjects during the examination: 1) the prone instability test. 2) the test for aberrant movement patterns during lumbar flexion test. 3) the straight leg raising test. 4) posterior-to-anterior mobility test, and 5) the test for age and strength of the hip abductor muscle following assessment of the dominant side. In particular, hip abductor muscle strength was evaluated using a dynamometer. Results: The test results showed that the number of positive responses for the five types of lumbar instability tests performed, was significantly related to the strength of the hip abductor muscle. The average hip abductor muscle strength in total subjects was $72.89{\pm}7.66N$, whereas the average hip abductor muscle strength in subjects who showed positive responses to more than four out of the five tests, was $44.70{\pm}5.79N$. Conclusion: The results demonstrated that the hip abductor muscle strength and lumbar instability were negatively correlated. The lower was the strength of the hip abductor muscle, the higher was the possibility of lumbar instability.

• 한국구조물진단유지관리공학회 논문집
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• 제22권2호
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• pp.98-104
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• 2018

콘크리트 비파괴강도 추정식은 일반적으로 콘크리트 강도를 결정하는데 사용된다. 그러나 기존의 추정식들은 대부분 제한된 실험 변수를 토대로 제안되어 배합조건, 강도특성 등이 다양한 실제 공용중 교량의콘크리트 압축강도 추정시 많은 오류를 포함한다. 본 연구에서는 297개 공용 교량의 정밀안전진단 결과 중 콘크리트 비파괴시험 및 현장 코어강도 시험결과를 토대로 콘크리트 부재의 코어강도와 비파괴 추정강도 평가결과를 비교분석하였다. 분석결과 분석이 이루어진 기존 추정식들 중 일본건축학회 CNDT소위원회 강도계산식이 다른 추정식에 비하여 실제파괴강도와의 오차가 가장적고 상관분석의 신뢰도도 가장높은 것으로 검토되었다. 그러나 이 추정식은 코어강도가 30 MPa이상일때 추정강도는 과소평가되는 것으로 나타났다. 이에 본 논문에서는 추정식에 의한 강도와 현장 코어강도사이의 관계를 활용하여 회귀분석을 통한 개선된 비파괴강도 추정식을 제안하였다.

• Advances in concrete construction
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• 제10권6호
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• pp.479-488
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• 2020

The experimental and numerical works were carried out on high performance fiber reinforced concrete (HPFRC) with w/cm ratios ranging from 0.25 to 0.40, fiber volume fraction (Vf)=0-1.5% and 10% silica fume replacement. Improvements in compressive and flexural strengths obtained for HPFRC are moderate and significant, respectively, Empirical equations developed for the compressive strength and flexural strength of HPFRC as a function of fiber volume fraction. A relation between flexural strength and compressive strength of HPFRC with R=0.78 was developed. Due to the complex mix proportions and non-linear relationship between the mix proportions and properties, models with reliable predictive capabilities are not developed and also research on HPFRC was empirical. In this paper due to the inadequacy of present method, a back propagation-neural network (BP-NN) was employed to estimate the 28-day compressive strength of HPFRC mixes. BP-NN model was built to implement the highly non-linear relationship between the mix proportions and their properties. This paper describes the data sets collected, training of ANNs and comparison of the experimental results obtained for various mixtures. On statistical analyses of collected data, a multiple linear regression (MLR) model with R2=0.78 was developed for the prediction of compressive strength of HPFRC mixes, and average absolute error (AAE) obtained is 6.5%. On validation of the data sets by NNs, the error range was within 2% of the actual values. ANN model has given the significant degree of accuracy and reliability compared to the MLR model. ANN approach can be effectively used to estimate the 28-day compressive strength of fibrous concrete mixes and is practical.

• Journal of Construction Engineering and Project Management
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• 제4권2호
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• pp.41-46
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• 2014

RCC consumes large quantities of natural resources like gravel stone and steel, and there is a need to investigate on an innovative material that utilizes limited quantities of natural resources but should have good mechanical strength. This study deals with the experimental investigation of strength evaluation of cementitious composites reinforced with polyolefin fibers from 0% to 2.5% (with interval of 0.5%), namely Polyolefin Fiber Reinforced Cementitious Composites (PL-FRCC) and developing statistical regression models for compressive strength, splitting-tensile strength, flexural strength and impact strength of PL-FRCC. Paired t-tests (for each PL fiber percentage 0 to 2.5%) bring out that there is significant difference in compressive and splitting-tensile strength when curing periods (3, 7, 28 days) are varied. Also, a strong relationship exists between the compressive and flexural strength of PL-FRCC. The proposed mathematical models developed in this study will be helpful to ascertain the mechanical strength of FRCC, especially, when the fiber reinforcing index is varied.

• 대한가정학회지
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• 제44권3호
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• pp.51-59
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• 2006

The purpose of this study is to determine the relevant variables of parent-leadership that influence family strength based on the transformational leadership and transactional leadership proposed by Bernard M. Bass and to investigate the primary impact of leadership on the subordinate's job satisfaction and job involvement to his/her supervisor. Therefore, this study will provide implications for the family through a diagnosis of the effect by leadership. The results of this research are as follows : 1) How is the relationship of parent-leadership and family strength? A positive correlation was found between transformational leadership scores and family strength. A negative correlation was found between nontransactional leadership scores and family strength. 2) How had transformational leadership and transactional leadership affected on the family strength? Transformational leadership had the strongest effect on family strength. How had the 7 sub- factors of transformational/transactional leadership affected family strength? Idealized influence and contingent reward had strong effect on family strength but management by except had a negative effect on family strength.

• Architectural research
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• 제15권1호
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• pp.53-58
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• 2013

High strength concrete is being used increasingly in mass structure projects. The purpose of this study is to investigate the influence of temperature during mixing, placing and curing on the strength development, hydration products and pore structures of high strength concrete in mass structures. The experiments were conducted with two different model walls, viz.: 1.5 m and 0.3 m under typical summer and winter weather conditions. The final part of this study deal with the clarification of the relationship between the long-term strength loss and the microstructure of the high strength concrete at high temperatures. Test results indicated that high elevated temperatures in mass concrete structures significantly accelerate the strength development of concrete at the early ages, while the long-term strength development is decreased. The long-term strength loss is caused by the decomposition of ettringite and increased the total porosity and amount of small pores.

• 한국농공학회지
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• 제17권3호
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• pp.3815-3832
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• 1975

This study was made to investigate various engineering properties of earth materials resulting from their changes in density and moisture content. The results obtained in this study are summarized as follows: 1. The finner the grain size is, the bigger the Optimum Moisture Content(OMC) is, showing a linear relationship between percent passing of NO. 200 Sieve (n) and OMC(Wo) which can be represented by the equation Wo=0.186n+8.3 2. There is a linear relationship of inverse proportion between OMC and Maximum Dry Density (MDD) which can be represented by the equation ${\gamma}$d=2.167-0.026Wo 3. There is an exponential curve relationship between void ratio (es) and MDD whose equation can be expressed ${\gamma}$d=2.67e-0.4550.9), indicating that as MDD increases, void ratio decreases. 4. The coefficent of permeability increases in proportion to decrease of the MDD and this increase trend is more obvious in coarse material than in fine material, and more obvious in cohesionless soil than in cohesive soil. 5. Even in the same density, the coefficient of permeability is smaller in wet than in dry from the Optimum Moisture Content. 6. Showing that unconfined compressive strength increases in proportion to dry density increase, in unsaturated state the compacted in dry has bigger strength value than the compacted in wet. On the other hand, in saturated state, the compacted in dry has a trend to be smaller than the compacted in wet. 7. Even in the same density, unconfined compressive strength increases in proportion to cohesion, however, when in small density and in saturated state, this relationship are rejected. 8. In unsaturated state, cohesion force is bigger in dry than in wet from OMC. In saturated state, on the other hand, it is directly praportional to density. 9. Cohesion force decreases in proportion to compaction rate decrease. And this trend is more evident in coarse matorial than in fine material. 10. Internal friction angle of soil is not influenced evidently on the changes of moisture content and compaction rate in unsaturated state, On the other hand in saturated state it is influenced density. 11. Cohesion force is directly proportional to unconfined compressive strength(qu), indicating that it has approximately 35 percent of qu in unsaturated state and approximately 70 percent of qu in saturated state.

• 한국언어정보학회지:언어와정보
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• 제14권1호
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• pp.113-144
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• 2010

The primary goal of this paper is to find a feasible way to answer the question: Does the similarity in meaning between verbs relate to the similarity in their subcategorization? In order to answer this question in a rather concrete way on the basis of a large set of English verbs, this study made use of various language resources, tools, and statistical methodologies. We first compiled a list of 678 verbs that were selected from the most and second most frequent word lists from the Colins Cobuild English Dictionary, which also appeared in WordNet 3.0. We calculated similarity measures between all the pairs of the words based on the 'jcn' algorithm (Jiang and Conrath, 1997) implemented in the WordNet::Similarity module (Pedersen, Patwardhan, and Michelizzi, 2004). The clustering process followed, first building similarity matrices out of the similarity measure values, next drawing dendrograms on the basis of the matricies, then finally getting 177 meaningful clusters (covering 437 verbs) that passed a certain level set by z-score. The subcategorization frames and their frequency values were taken from the ICE-GB. In order to calculate the Selectional Preference Strength (SPS) of the relationship between a verb and its subcategorizations, we relied on the Kullback-Leibler Divergence model (Resnik, 1996). The SPS values of the verbs in the same cluster were compared with each other, which served to give the statistical values that indicate how much the SPS values overlap between the subcategorization frames of the verbs. Our final analysis shows that the degree of overlap, or the relationship between semantic similarity and the subcategorization frames of the verbs in English, is equally spread out from the 'very strongly related' to the 'very weakly related'. Some semantically similar verbs share a lot in terms of their subcategorization frames, and some others indicate an average degree of strength in the relationship, while the others, though still semantically similar, tend to share little in their subcategorization frames.