• 한국토양비료학회지
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• 제43권5호
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• pp.637-643
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• 2010

석회고토 및 패화석비료를 대체할 수 있는 토양개량제로 활용가치가 높은 굴껍질을 사과 '감홍' 재배 과수원에 시용하여 고두병 발생에 미치는 효과를 검토하였다. 석회고토와 굴껍질을 처리한구는 무처리구에 비해 표토와 심토의 토양 pH와 치환성 칼슘 함량이 증가된 반면, 치환성 나트륨 함량은 차이가 없었다. 사과의 고두병 발생비율은 무처리구가 10.4%로 가장 높았고 굴껍질 4 Mg$ha^{-1}$ 이상 처리할 경우 3.7% 이하로 유의적인 감소를 보였으며 석회고토 처리구는 8.9%로 무처리구와 비슷한 수준이었다. 굴껍질 시용량과 수확기 표토 및 심토의 pH와 치환성 칼슘 함량은 고두병 발병비율과 고도로 유의적인 부의상관을 보였다. 고두병 발병비율을 경감시킬 수 있는 굴껍질 시용량은 4 Mg $ha^{-1}$ 이지만 시험 후 토양의 치환성 칼슘 함량, pH 및 과실중량, 수량 등을 감안할 때 최적의 굴껍질 시용량은 2 Mg $ha^{-1}$로서 석회소요량과 같았다.

• 한국산학기술학회논문지
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• 제18권1호
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• pp.310-315
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• 2017

대규모 건설공사 현장에서는 발파공사에 대한 표준발파패턴과 시험발파패턴의 발파진동추정식의 상이에 따른 설계변경의 반영 문제로 시공사, 건설사업관리자, 발주처간의 갈등요인을 해소하기 위한 체계적인 자료의 수집 및 분석 과정을 통하여 효율적인 대책수립이 필요한 실정이다. 발파진동에 의한 인접 구조물에 미치는 영향을 여러 각도로 평가하려는 연구들은 계속 되어 왔으나, 노천발파를 수행하면서 현장계측의 진동파형을 분석하여 인접 건축물의 안전성을 확보하고 현장여건에 적합한 발파공법을 연구한 사례는 미미한 실정이다. 따라서 현장여건에 적합하고 경제적이며 효율적인 발파작업을 수행할 수 있도록 시험발파를 통하여 발파패턴 선정의 개선방안을 제시하는 것이 필요하다. 본 연구에서는 실제 도로확장공사 현장에서 시험발파를 통한 표준발파공법 및 진동규제기준별로 적용되는 이격 거리를 기준으로 노천 발파작업을 수행하여 발파진동 값을 계측하고 이를 통한 발파공법별 진동예측식을 회귀분석 전산프로그램을 이용하여 신뢰수준 95%의 K, n, R등을 산출하였다. 시험발파 대상지역의 발파허용진동기준을 0.3cm/sec로 설정하고 노천발파지침의 발파진동추정식과 시험발파의 발파진동추정식에 따른 이격 거리별 장약량과 발파공법을 비교분석한 결과 사업비가 증가하는 요인을 도출할 수 있었다. 또한, 노천발파 작업 중 인접 구조물에 대한 계측 및 분석을 수행하고 노천발파지점과 가장 인접한 구조물을 선정하여 발파진동 계측 및 평가를 시행하여 노천발파공사를 완료하는 과정에서 나타난 노천발파 설계 시공 지침에서의 시험발파 절차 및 해석방법에 대한 문제점을 분석하여 개선방안을 제시하였다.

• 터널과지하공간
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• 제24권1호
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• pp.1-10
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• 2014

본 논문에서 트럭의 고장 발생 가능성과 파쇄기의 처리 용량 변화를 고려하여 노천광산 소밸-트럭 운반시스템의 시뮬레이션을 수행한 사례연구 결과를 제시한다. 강원도 동해시에 위치한 쌍용자원개발 석회석 노천광산을 연구지역으로 선정하고, 시뮬레이션 알고리즘을 설계 하였다. GPSS/H 시뮬레이션 언어를 이용하여 설계된 시뮬레이션 알고리즘들을 콘솔 프로그램 형식의 시뮬레이터로 개발하였다. 또한, 연구지역의 현장조사를 통해 시뮬레이터에 입력되는 인자 값들은 직접 측정하였다. 시뮬레이션 결과 40시간 빈도의 트럭 고장 발생 가능성을 고려할 경우에는 7대의 트럭을 시스템에 투입하는 것이 하루 평균수익을 73,775 USD로 최대화할 수 있는 것으로 분석되었다. 또한, 파쇄기의 처리 용량은 1,300 thp로 운영하는 것이 연구지역의 쇼밸-트럭 운반 시스템의 효율을 높일 수 있는 것으로 분석되었다.

• 통상정보연구
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• 제12권1호
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• pp.179-202
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• 2010

Broadcasting services sector has been facing strong public pressure to shift gears from regulation to deregulation since mid-1990s, where a triggering role was played particularly by rapid development of IT technology and content digitization. Major agenda was how to reduce regulatory divides between more liberal telecommunication sector and less liberal broadcasting. After all, common solution package worldwide was for the latter to switch over from network-dependent(vertical) to network-independent(horizontal) regulation, and to facilitate more open and competitive transmission with content market kept protected. This is no other than decoupling content provision from broadcasting and promoting market access towards the latter. Policy experiences of US and UK show that there exists a complementary relationship between quantitative and qualitative restrictions in implementing such deregulation. While mitigating quantitative ownership regulations in broadcasting, they also sought to systematize, so-called, PIT(public interest test) as a qualitative safety device to cope with the risk of losing fundamental public values accordingly in broadcasting. Recent domestic progress in broadcasting legislation in 2009, however, seems to overlook the growing importance of PIT in the process of deregulation. Bearing this motivation in mind and taking account of the relevant WTO disciplines, this paper is to address policy issues and suggestions for PIT in Korea's broadcasting services sector.

• 음성과학
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• 제13권1호
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• pp.95-105
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• 2006

The primary goal of therapeutic intervention in dysarthric speakers is to increase the speech intelligibility. Decision of critical features to increase the intelligibility is very important in speech therapy. The purpose of this study is to know the effects of pitch increasing training (PIT) on speech of a subject with Parkinson's disease (PD). The PIT program is focused on increasing pitch while a vowel is sustained with the same loudness. The loudness level is somewhat higher than that of the habitual loudness. A 67-year-old female with PD participated in the study. Speech therapy was conducted for 4 sessions (200 minutes) for one week. Before and after the treatment, acoustic, perceptual and speech naturalness evaluation was peformed for data analysis. Speech and voice satisfaction index (SVSI) was obtained after the treatment. Results showed Improvements in voice quality and speech naturalness. In addition, the patient's satisfaction ratings (SVSI) indicated a positive relationship between improved speech production and their (the patient and care-givers) satisfaction.

• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2000년도 High Temperature Superconductivity Vol.X
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• pp.276-279
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• 2000

When high temperature superconducting tapes is fabricated using the PIT (Powder In Tube) method, the length of HTS tapes is increased more than 500 ${\sim}$ 1,000 times of initial powder packed billet. On mechanical processing, heterogeneous properties between the ceramic superconducting core and Ag/Ag alloy sheath occur the non-uniformity deformation as like sausaging that deteriorate the critical current properties of HTS tapes. In this study, we investigated the workability of Bi-2223/Ag/Ag alloy sheath tapes fabricated by the PIT method involving a number of different mechanical processes, multi drawing and rolling. In order to obtain the high critical current density and high uniformity of Bi-2223/Ag sheath tapes, the influences of powder packing density, drawing die angle and rolling parameters were studied. We found that the roll diameter is an important variable in the rolling process, as critical current of tapes rolled using 250 mm rolls was higher than that using 150 mm rolls.

• 한국가구학회지
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• 제26권2호
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• pp.179-185
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• 2015

A study was carried out to observe the 1% aqueous safranine solution flow speed in longitudinal and radial directions of softwood G. biloba, ring-porous wood A. altissima, and diffuse- porouswood D. kaki. In radial direction, ray cells and in longitudinal direction tracheids, vessel and wood fiber were considered for the measurement of liquid penetration speed at less than 12% moisture contents (MC). The length, lumen diameter, pit diameter, end wall pit diameter and the numbers of end wall pits determined for the flow rate. The liquid flow in the those cells was captured via video and the capillary flow rate in the ones were measured. Vessel in hardwood species and tracheids in softwood was found to facilitate prime role in longitudinal penetration. Radial flow speed was found highest in ray parenchyma of G. biloba. Anatomical features like the length and diameter, end-wall pit numbers of ray parenchyma were found also responsible fluid flow differences. On the other hand, vessel and fiber structure affected the longitudinal flow of liquids. Therefore, the average liquid penetration depth in longitudinal tracheids of G. biloba was found the highest among all cells considered in D. kaki and A. altissima.

• 대한소아치과학회지
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• 제23권4호
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• pp.906-914
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• 1996

Due to the various reason, sealing of pit & fissure might be imperfect. One of these reason can be the fracture of sealant material because of the low hardness value of sealing material. The purpose of this in vitro study was to evaluate the microhardness of two different curing type pit and fissure sealants: Dual-cure and Light-cure. The result from the present study can be summarized as follows: 1. All pit and fissure sealants that used in this study showed statistically significant difference in their microhardness of upper and lower surface. (P <0.05) 2. Except of lower surface of teethmate, microhardness of 40-second curing sealant was statistically higher than that of 20-second curing sealant. (P <0.05) 3. In comparison of sealants, microhardness of dual-cure sealant was statistically higher than that of light-cure sealant. Above results suggest that the use of dual-cure sealant and longer curing time are recommended.

• 한국항만학회지
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• 제15권1호
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• pp.87-97
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• 2001

The calculation of earthwork plays a major role in plan or design of many civil engineering projects, and thus it has become very important to advanced the accuracy of earthwork calculation. Current method used for estimating the volume of pit excavation assumes that the ground profile between the grid points is linear(trapezoidal rule), or nonlinear(simpson's formulas). In this paper the spot height method, least square method, and chamber formulas, Chen and Lin method are compared with the volumes of the pits in these examples. As a result of this study, algorithm of chen and Lin me쇙 by spline method should provide a better accuracy than the spot height method, least square method, chamber formulas. The Chen and Lin formulas can be used for estimating the excavation volume of a pit divide into a grid with unequal intervals. From the characteristics of the cubic spline polynomial, the modeling curve of the Chen and Lin method is smooth and matches the ground profile well. Generally speaking, the nonlinear profile formulas provide better accuracy than the linear profile formulas. The mathematical model mentioned make an offer maximum accuracy in estimating the volume of a pit excavation.

• Geomechanics and Engineering
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• 제9권3호
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• pp.275-286
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• 2015

A new method is presented to recover missing deformation data of lateral walls of foundation pit when the monitoring is interrupted; the method is called Dynamic Mathematical Model - Parameter Interpolation. The deformation of lateral walls of foundation pit is mainly affected by the type of supporting structure and the situation of constraints, therefore, this paper mainly studies the two different kinds of variation law of deep horizontal displacement when the lateral walls are constrained or not, proposes two dynamic curve models of normal distribution type and logarithmic type, deals with model parameters by interpolating and obtains the parameters of missing data, then missing monitoring data could be Figured out by these parameters. Compared with the result from the common average method which is used to recover missing data, in the upper 2/3 of the inclinometer tube, the result by using this method is closer to the actual monitoring data, in the lower 1/3 part of the inclinometer tube, the result from the common average method is closer to the actual monitoring data.