• Advances in concrete construction
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• 제6권6호
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• pp.561-583
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• 2018

A variety of polycarboxylate ether (PCE)-based superplasticizers are commercially available. Their influence on the rheological retention and slump loss in respect of concrete differ considerably. Fluidity and slump loss are the cardinal features responsible for the quality of concrete. These are related to the dispersion of cement particles and the hydration process which are greatly influenced by type of polycarboxylate ether (PCE)-based superplasticizers. On the backdrop of relatively less studies in the context of rheological retention of high strength self-consolidating concrete (HS-SCC), the experimental investigations were carried out aiming at quantifying the effect of the six different PCE polymers (PCE 1-6) on the rheological retention of HS-SCC mixes containing two types of Ordinary Portland Cements (OPC) and unwashed crushed sand as the fine aggregate. The tests that were carried out included $T_{500}$, V-Funnel, yield stress and viscosity retention tests. The supplementary cementitious materials such as fly ash (FA) and micro-silica (MS) were also used in ternary blend keeping the mix paste volume and flow of concrete constant. Low water to binder ratio was used. The results reveal that not only the PCEs of different polymer groups behave differently, but even the PCEs of same polymer groups also behave differently. The study also indicates that the HS-SCC mixes containing PCE 6 and PCE 5 performed better as compared to the mixes containing PCE 1, PCE 2, PCE 3 and PCE 4 in respect of all the rheological tests. The PCE 6 is a new class of chemical admixtures known as Polyaryl Ether (PAE) developed by BASF to provide better rheological properties in even in HS-SCC mixes at low water to binder mix. In the present study, the PCE 6, is found to help not only in reduction in the plastic viscosity and yield stress, but also provide good rheological retention over the period of 180 minutes. Further, the early compressive strength properties (one day compressive strength) highly depend on the type of PCE polymer. The side chain length of PCE polymer and the fineness of the cement considerably affect the early strength gain.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1415-1421
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• 2006

Proper nutritional management during the dry period is required to prevent metabolic disorders during the time of parturition and for potential increase milk yield during early lactation, especially under the heat of summer. The effect of prepartum diets on partitioning of nitrogen (N), calcium (Ca), phosphorus (P), magnesium (Mg) and potassium (K) during dry period and early lactation in summer was investigated. Nine cows were assigned to two groups and fed either control (group C: four cows) or high concentrate (group H: five cows) diets to meet 110% of their requirements before parturition. The proportion of concentrate in control diet was 35%, and that in the high concentrate diet was 45%. After parturition, all cows were fed the same diets ad libitum during lactation. Balance trials were conducted at 9, 8 and 7 days before parturition and at 12, 13 and 14 days after parturition. Before parturition, dry matter intake (DMI), DM and NFE digestibility in group C tended to be lower than those in group H. The retention of N (p<0.01) and P (p<0.05) in group C during the dry period was significantly lower than those in group H. The retention of Mg in group C during the dry period tended to be lower than in group H. The concentration of plasma NEFA in group C tended to be higher than in group H during dry period. The prepartum diet did not have an apparent effect on DMI and milk yield at 2 weeks after parturition and N, Ca, P, Mg and K balance after parturition.

• 대한치과교정학회지
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• 제41권3호
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• pp.154-163
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• 2011

본 연구는 교합 상태를 객관적이고 정량적으로 평가하기 위해 개발된 American Board of Orthodontics objective grading system (ABO-OGS)을 이용하여 교정치료 후 나타나는 재발 경향을 평가하고 이에 영향을 줄 수 있는 요소들과의 상관관계를 알아보고자 시행되었다. 부산대학교, 경희대학교와 단국대학교 치과병원 교정과에서 포괄적 교정치료를 받은 환자 중 치료종료 후 2년 이상의 유지기간을 갖는 80명의 환자를 대상으로 초진 시(T1)의 peer assessment rating (PAR) index, 치료 후(T2)와 유지 후(T3) 시기의 ABO-OGS를 측정하여 T2와 T3 간의 변화 양상을 각 항목별로 측정하였고, 나이, 성별, Angle 분류, 발치 여부, 유지기간, 초진 시의 상태와의 상관관계를 조사하기 위해 다중 회귀분석을 시행하여 다음과 같은 결과를 얻었다. T2 시기와 비교하여 T3 시기에 ABO-OGS의 7개 항목 중 치아 배열(alignment)은 악화되었으며, 교합 접촉(occlusal contact)과 치간 접촉(interproximal contact)은 개선되었고, 나머지 4개의 항목에서는 유의한 차이가 없었다. 다중 회귀분석을 시행한 결과, 유의한 회귀모형은 치아 배열(alignment), 교합 관계(occlusal relationship), 수평피개(overjet), 치간 접촉(interproximal contact) 항목이었으나, 회귀 모형들의 설명력이 낮았으며, 연령, 성별, Angle 분류, 발치 여부, 유지기간, 초진시의 상태(initial PAR index, T1)는 T2 시기와 T3 시기의 ABO-OGS 변화량을 설명하는 데 큰 영향을 미치지는 않는 것으로 보인다.

• 한국전문물리치료학회지
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• 제11권3호
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• pp.11-18
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• 2004

This study is aimed at investigating the influence of different quantitative knowledge of results on the measurement error during lumbar proprioceptive sensation training. Twenty-eight healthy adult men participated and subjects were randomly assigned into four different feedback groups(100% relative frequency with an angle feedback, 50% relative frequency with an angle feedback, 100% relative frequency with a length feedback, 50% relative frequency with a length feedback). An electrogoniometer was used to determine performance error in an angle, and the Schober test with measurement tape was used to determine performance error in a length. Each subject was asked to maintain an upright position with both eyes closed and both upper limbs stabilized on their pelvis. Lumbar vertebrae flexion was maintained at $30^{\circ}$ for three seconds. Different verbal knowledge of results was provided in four groups. After lumbar flexion was performed, knowledge of results was offered immediately. The resting period between the sessions per block was five seconds. Training consisted of 6 blocks, 10 sessions per one block, with a resting period of one minute. A resting period of five minutes was provided between 3 blocks and 4 blocks. A retention test was performed between 10 minutes and 24 hours later following the training block without providing knowledge of results. To determine the training effects, a two-way analysis of variance and a one-way analysis of variance were used with SPSS Ver. 10.0. A level of significance was set at .05. A significant block effect was shown for the acquisition phase (p<.05), and a significant feedback effect was shown in the immediate retention phase (p>.05). There was a significant feedback effect in the delayed retention phase (p<.05), and a significant block effect in the first acquisition phase and the last retention phase (p<.05). In conclusion, it is determined that a 50% relative frequency with a length feedback is the most efficient feedback among different feedback types.

• 대한소아치과학회지
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• 제36권3호
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• pp.420-426
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• 2009

본 연구의 목적은 유치열기 3급 부정 교합 환아에서 facemask를 이용한 악정형 치료 후 골격적 변화와 치료 후 나타나는 재발 양상을 평가하는 것이다. 유치열기 3급 부정교합 환아 15명을 대상으로 구내장치로 bonded expander, 구외장치로 facemask를 이용한 악정형 치료를 평균 12 개월 동안 시행하였으며, 1년 간의 follow-up 기간 동안 유지 장치는 사용되지 않았다. 치료 시작 전, 치료 직후, 치료 1년 후에 측면두부방사선사진을 촬영하고 전후방 및 수직적 골격관계와 연조직의 변화를 비교분석하였다. 모든 환아에서 치료 직후, 유의할 만한 골격적 전후방 관계의 변화를 보였고 1년 간의 follow-up 기간 동안 재발되는 경향을 보였으나 치료 시작 전과 비교하여 치료 효과는 유지되었다. 수직적 골격적 변화는 치료 직후 증가되었으나 1년 간의 follow-up 기간 동안 다시 감소하여 치료 시작 전과 비교하여 차이를 보이지 않았다. 연조직의 변화는 facial convexity 및 상순의 위치가 치료 직후 개선됨을 보였고 1년 간의 follow-up 기간 동안에도 치료 전과 비교하여 치료효과는 유지되었다. 하순의 위치는 치료 직후에 유의할 만한 변화를 보이지 않았다. Facemask는 유치열기 3급 부정교합에 있어서 효과적인 치료 방법이며, 안정적인 치료 결과를 위해서는 적절한 형태의 유지장치가 고려되는 것이 바람직하다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권7호
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• pp.1007-1013
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• 2004

This experiment was conducted to investigate the effect of cadmium levels on weight gain, nutrient digestibility and the retention of iron, copper and zinc in tissues of growing pigs. A total of one hundred and ninety-two crossbred pigs (barrows, Duroc$\times$Landrace$\times$Yorkshine, 27.67$\pm$1.33 kg of average initial body weight) were randomly allotted to four treatments. Each treatment had three replicates with 16 pigs per pen. The corn-soybean basal diets were supplemented with 0, 0.5, 5.0, 10.0 mg/kg cadmium respectively, and the feeding experiment lasted for eight-three days. Cadmium chloride was used as cadmium source. The results showed that pigs fed the diet containing 10.0 mg/kg cadmium had lower ADG and FCR than any other treatments (p<0.05). Apparent digestibility of protein in 10.0 mg/kg cadmium-treated group was lower than that of other groups (p<0.05). There was lower iron retention in some tissues of 5.0 mg/kg and 10.0 mg/kg cadmium treatments (p<0.05). However, pigs fed the diet 10.0 mg/kg cadmium had higher copper content in most tissues than that of any other groups (p<0.05). There was a significantly increase of zinc retention in kidney of 10.0 mg/kg cadmium additional group (p<0.05) and zinc concentrations in lymphaden, pancreas and heart of 10.0 mg/kg cadmium treatment were lower than those of the control (p<0.05). This study indicated that relatively high cadmium level (10.0 mg/kg) could decrease pig growth performance and change the retention of iron, copper and zinc in most tissues during extended cadmium exposure period.

• 한국축산시설환경학회지
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• 제3권2호
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• pp.97-104
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• 1997

This research was carried out to determine the effect of dietary calcium(Ca) levels(low : 0.29, medium : 0.65 and high : 1.07%) on the digestibility, excretion and retention of nitrogen(N) phosphorus (P) in pigs fed diets supplemented with phytase(750U/kg). Twelve growing-finishing pigs(average body weight: 35kg) were divided into 3 groups and these pigs were reared in metabolism cage. After 10 days adaptation period, N and P balance experiments were carried out for 4 days. The results were summarized as follows ; 1. The High-Ca group was lower than the others in digestibility of P(Low-Ca and Medium-Ca group). 2. The amount of daily excretion of urinary N were 19.6g in Low-Ca group and 16.7g in high-Ca group. The High-Ca group was the lowest(22.71%/d) in the total N excretion. 3. The High-Ca group was the highest and the Low-Ca group the lowest in fecal P excretion. The urinary P excretions per day were 1.90g in Low-Ca group and 0.04g in High-Ca group. The medium-Ca group showed the lowest total P excretion(4.57g/d). 4. The N retention of the High-Ca group(20.50g) was greater than that of the Low-Ca group and Medium-Ca(5.02)g was the highest and the Low-Ca groups(3.92g) was the lowest in the P retention. These results indicate that dietary Ca level was an important factor influencing N and P utilization in pigs.

• 융합정보논문지
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• 제9권9호
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• pp.210-218
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• 2019

본 연구의 목적은 동기부여 및 조직공정성과 재직의도와의 상호 관계성을 파악하여 합리적인 근무환경관리의 기초자료를 마련하고자 시행하였다. 자료 수집은 2019년 3월 1일부터 2019년 4월 12일까지 서울 경기 충청 전라지역에 치과 병 의원에서 근무하는 임상치과위생사를 편의표본추출 하였으며, 자기기입식 방법으로 작성하게 하였다. 동기부여와 조직공정은 유의한 양의 상관관계가 나타났으며, 재직의도와도 양의 상관관계를 보였다. 조직공정성은 재직의도와 양의 상관관계를 나타내었다. 임상치과위생의 동기부여, 조직공정성, 재직의도 간의 연관성이 있음을 알 수 있었고, 따라서 치과위생사들의 재직의도를 높이기 위한 적극적인 동기부여 프로그램 적용과 올바른 조직공정성을 토대로 한 근속기간 확립으로 업무효율성을 높일 필요가 있을 것으로 사료된다.

• 한국지반공학회논문집
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• 제37권1호
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• pp.17-27
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• 2021

불포화토의 함수특성시험은 오랜 기간이 소요된다. 이를 줄이기 위하여 고압 공기합입치 디스크를 마이크로 멤브레인으로 대체하였다. 마이크로 멤브레인을 적용한 함수특성시험을 수행하여 그 결과를 세라믹 디스크를 이용한 시험결과와 비교하였다. 5개 지역에 대하여 많은 시료를 분석한 결과 마이크로 멤브레인을 적용한 함수특성곡선은 세라믹 디스크를 이용한 시험결과와 유사한 것으로 검증되었다. 이로 인하여 마이크로 멤브레인을 이용하여 신속한 절차기법을 개발하여 많은 양의 함수특성 성과를 획득할 수 있게 되었다. 그리고 마이크로 멤브레인을 이용한 시험을 포함하여 총 5개지역 29개 시료에 대한 함수특성곡선 데이터베이스를 구축하였다. 국내 풍화토에 대하여 불포화 수리특성은 세 그룹으로 분류할 수 있었다. 각 그룹은 van Genuchten 모델 물성치 n값에 따라서 분류되며 n값은 간극비의 함수로 상관관계를 찾을 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제29권5호
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• pp.689-694
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• 2016

The objective of the current study was to evaluate the effect of supplementation of either L-methionine (L-Met) or DL-methionine (DL-Met) to diets of starter pigs on nitrogen (N) balance, metabolism, and serum amino acid profile. Eighteen crossbred ($Duroc{\times}Landrace{\times}Yorkshire$) barrows weighing $15.45{\pm}0.88kg$ were randomly allotted to 1 of 3 diets with 6 pigs per treatment. The diets included a basal diet (Met-deficient diet) containing 0.24% standardized ileal digestibility Met with all other essential nutrients meeting the pig's requirements. The other two diets were produced by supplementing the basal diet with 0.12% DL-Met or L-Met. The experiment lasted for 18 days, consisting of a 13-day adaptation period to the diets followed by a 5-day experimental period. Pigs were fed ad libitum and free access to water throughout the experiment. Results showed that the supplementation of either L-Met or DL-Met improved N retention, and serum methionine concentration, and decreased N excretion compared with basal diet (p<0.01). The N retention of pigs fed diets supplemented with the same inclusion levels of DL-Met or L-Met were not different (p>0.05). In conclusion, on equimolar basis DL-Met and L-Met are equally bioavailable as Met sources for starter pigs.