• 한국초지조사료학회지
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• 제20권3호
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• pp.185-192
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• 2000

This experiment was canied out to determine the effect of management practices on the quality of round baled oat silage at experimental field of Grassland and Forage Crops division, National Livestock Research Institute, RDA, Suwon from 1997 to 1998. The experiments are consist of randomized block design with 3 replications. The treatments are 3 wilting dates(0, 2 and 4 days), 3 wrap colors(white, black and green and 3 inoculant(untreated, Inoculant A and Inocuant B). The crude protein(CP) content was increased by prolonged wilting periods, but the effect of wrap color and inoculant were not founded. Acid detergent fiber(ADF) and neutral detergent fiber(NDF) content of all silages were not founded significant difference, but in vitro dry matter digestibility of oat silage with inoculant was significantly higher compare with control. Wilting treatment increased the mean silage acidity compare with control and inoculant treatment significantly reduced silage acidity. Wrap color did not influence the silage acidity. Wilting or inoculant treatments increased lactic acid content but, decreased the content of acetic and butyric acid. The quality grade of all silage were grade 3, except inoculant treated silage. Wilting or inoculant decreased silage DM loss, but wrap color did not effect on siage DM loss. The result of this study indicate that wilting for 2-4 days and inoculant will improve the silage fermentation and quality of round baled oat silage. (Key words : Oat, Wilting, Inoculant, Wrap color, Round bale silage)

• 천문학회지
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• 제48권2호
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• pp.113-123
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• 2015

We present observational results from optical long-slit spectroscopy of parsec-scale jets of DG Tau. From HH 158 and HH 702, the optical emission lines of Hα, [O i] λλ6300, 6363, [N ii] λλ6548, 6584, and [S ii] λλ6716, 6731 are obtained. The kinematics and physical properties (i.e., electron density, electron temperature, ionization fraction, and mass-loss rate) are investigated along the blueshifted jet up to 650′′ distance from the source. For HH 158, the radial velocity ranges from −50 to −250 km s⁻¹. The proper motion of the knots is 0.′′196 − 0.′′272 yr⁻¹. The electron density is ∼10⁴ cm⁻³ close to the star, and decreases to ∼10² cm⁻³ at 14′′ away from the star. Ionization fraction indicates that the gas is almost neutral in the vicinity of the source. It increases up to over 0.4 along the distance. HH 702 is located at 650′′ from the source. It shows ∼ −80 km s⁻¹ in the radial velocity. Its line ratios are similar to those at knot C of HH 158. The mass-loss rate is estimated to be about ∼ 10⁻⁷ M_⊙ yr⁻¹, which is similar to values obtained from previous studies.

• 전력전자학회논문지
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• 제20권5호
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• pp.410-420
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• 2015

This paper provides a comparison of power converter loss and thermal description for voltage source and current source type 5 MW-class medium-voltage topologies of wind turbines. Neutral-point clamped three-level converter is adopted for a voltage source type topology, whereas a two-level converter is employed for current source type topology, considering the popularity in the industry. To match the required voltage level of 4160 V with the same switching device of IGCT as in the voltage source converter, two active switches are connected in series for the case of current source converter. Transient thermal modeling of a four-layer Foster network for heat transfer is done to better estimate the transient junction and case temperature of power semiconductors during various operating conditions in wind turbines. The loss analysis is confirmed through PLECS simulations. Comparison result shows that the VSC-based wind turbine system has higher efficiency than the CSC under the rated operating conditions.

• 한국식품과학회지
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• 제11권3호
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• pp.188-191
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• 1979

5-GMP의 열 분해 반응을 pH 5.52에서 7.00의 범위에서 조사하였다. 그 반응 속도는 일차 반응으로 나타났으며, 용액의 pH가 $pKa_2$일 때 반응속도가 가장 컸다. 5'-GMP의 분해 반응은 온도 의존성을 나타냈으며, $93^{\circ}C$에서 $108^{\circ}C$ 범위에서 Arrhenius식을 따르고 있었고, 반응 속도 상수는 $pKa_2$ 이상의 중성 용액 근처에서는 온도 및 pH의 함수로서 다음과 같이 표시되었다. $$K=4.19{\times}10^{26}\;Exp[-1.3(pH+E/RT)]$$

• 한국가스학회지
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• 제3권3호
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• pp.39-44
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• 1999

일반강구조물로 많이 사용되고 있는 SM20C, BsC3 및 STC4H에 대하여, 여러 가지 부식환경(지하수($6,000{\Omega}{\cdot}cm$), $0.5\%\;H_2SO_4$ 및 $0.5\%HNO_3$)침지하에서의 부식특성 및 건조상태에서의 찰과마멸특성실험에 의한 이종금속간의 찰과마멸특성을 고찰하였다. 침지시험의 경우, 이들 금속의 전위값은 $HNO_3$, 지하수, $H_2SO_4$ 순으로 크게 나타났으며, BsC3을 제외한 동재금속보다 이종금속의 전위가 높았다. 동종재인 SM20C의 마멸은 회전측의 경우가 이동측보다 약 1.9배 증가하였으며, 이는 마찰력에 의한 표면경화가 그 원인인 것으로 추측된다.

• Clinics in Shoulder and Elbow
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• 제27권1호
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• pp.88-107
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• 2024

The aim of this systematic review was to collect evidence on the following 10 technical aspects of glenoid baseplate fixation in reverse total shoulder arthroplasty (rTSA): screw insertion angles; screw orientation; screw quantity; screw length; screw type; baseplate tilt; baseplate position; baseplate version and rotation; baseplate design; and anatomical safe zones. Five literature libraries were searched for eligible clinical, cadaver, biomechanical, virtual planning, and finite element analysis studies. Studies including patients >16 years old in which at least one of the ten abovementioned technical aspects was assessed were suitable for analysis. We excluded studies of patients with: glenoid bone loss; bony increased offset-reversed shoulder arthroplasty; rTSA with bone grafts; and augmented baseplates. Quality assessment was performed for each included study. Sixty-two studies were included, of which 41 were experimental studies (13 cadaver, 10 virtual planning, 11 biomechanical, and 7 finite element studies) and 21 were clinical studies (12 retrospective cohorts and 9 case-control studies). Overall, the quality of included studies was moderate or high. The majority of studies agreed upon the use of a divergent screw fixation pattern, fixation with four screws (to reduce micromotions), and inferior positioning in neutral or anteversion. A general consensus was not reached on the other technical aspects. Most surgical aspects of baseplate fixation can be decided without affecting fixation strength. There is not a single strategy that provides the best outcome. Therefore, guidelines should cover multiple surgical options that can achieve adequate baseplate fixation.

• 유기물자원화
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• 제2권1호
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• pp.87-98
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• 1994

슬러지 발생량은 정수처리공정에서 부터 슬러지 농축 및 탈수에 이르는 과정을 최적화하므로써 감량화할 수 있다. 본 논문에서는 탈수 및 건조기법에 의하여 정수처리공정에서 발생하는 슬러지의 함수율을 낮추어 슬러지 발생량을 줄이는 방법에 대하여 연구하였다. 탈수효율향상을 위한 polymer 투입량 및 교반조건등을 최적화하고, 온도에 따른 슬러지의 중량변화에 대하여 관찰하였다. 탈수효율은 polymer의 종류보다 교반강도에 의한 영향이 크고, pH의 영향도 큰 것으로 나타났다. 최적 polymer 주입농도는 1.5mg-polymer/g-TSS이었고, pH가 약산성이나 약알카리성 조건에서 탈수효율이 양호한 것으로 나타났다. 교반강도는 낮을수록(10,000ses-1이하) 효율이 향상되었고, 속도구배(G)보다 GT값이 중요한 영향인자인 것으로 나타났다. 자유수의 건조는 $100^{\circ}C$ 전후, 화학적 결함수는 $300^{\circ}C$ 근방에서 증발하며, 유기물질은 약 $300-600^{\circ}C$ 구간에서 산화되어 증발하는 것으로 나타났다. 취수원 수질에 따라 강열감량은 약 15-40%로 나타났으며, 화학적 결합수에 의한 감량이 약 10-20%, 유기물질에 의한 감량이 약 4-20%인 것으로 나타났다.

• Journal of Pharmaceutical Investigation
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• 제38권4호
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• pp.229-234
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• 2008

In the present study, chitosan-glycerophosphate sodium salt solution as a thermosensitive system (TSS) was used to formulate a temperature-sensitive drug delivery system (TSDDS) containing acetaminophen (AAP). The optimized TSS was prepared by measuring gelation temperature, gelation time and rheological properties of TSS. The optimized gelation temperature and time of TSS were $36^{\circ}C$ and 100 seconds, respectively. The viscosity of TSS was also suitable for maintaining gel structure at $37.2^{\circ}C$. The release profiles of TSDDS in PBS/pH 7.4 with various apparatuses and mass loss of TSDDS were investigated. The time required to release 50% of AAP from TSDDS ($t_{50%}$) was 120 min with the formation of pore on the surfaces, which was 2 times longer than that from AAP-chitosan gel. In addition, TSDDS was degraded approximately 80% within 4 hr and then degraded slowly for 20 hrs. In conclusion, AAP-TSS (TSDDS) formulated in this study might be suitable for some specific uses such as subcutaneous injection and rectal formulation.

• 대한화장품학회지
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• 제23권3호
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• pp.97-100
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• 1997

These days, the raw materials that have the cell recovering effect are used commonly in cosmetics. In this study, six materials were rested for the characteristics of recovering effect both on vivo and in vitro. Tested raw materials were Soypol, 3-APPA, Apple extract, Polygonatum japonicum extract, Scutellarkd baicalensis extract, Aloe extract. Among these materials, Soypol and 3-APPA were synthesized and others were made by extraction at the Pacific R&D Center. Human forearm skin and cultured skin cell were damaged by sodium lauryl sulfare and then raw materials were applied for open treatment on SLS damaged human skin or cells. The recovering effects of raw materials in vivo were evaluated by measuring transepidermal water loss, skin hydration and erythema and in vitro effects of proliferationg cells were assessed by neutral red uptake assay. In the in vivo study, only the evaluation by TEWL showed correlation with the visual score. Our of six materials, 3-APPA had the most positive effect in both in vivo and in vitro studies and the correlation was r=0.8286 (p=0.042).

• Asian-Australasian Journal of Animal Sciences
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• 제3권4호
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• pp.299-303
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• 1990

Twenty-four Harnai lambs 6 to 7 month old, weighing $16{\pm}2kg$ were used in a completely randomized design in growth and digestibility trials to study fourwing saltbush ratio supplemented with cotton seed cake. The animal were divided at random into three groups of 8 animals each. Three iso-nitrogenous (10.5% CP) experimental rations (1, 2 and 3) containing wheat straw + lucerne hay (24:76); fourwing saltbush (Atriplex canescens) + cotton seed cake (71:29); and wheat straw + cottonseed cake (41:59); respectively, were allotted to each group randomly. All the animals were taken out for grazing in a dormant native range for about 3 hours in the afternoon during the growth trial. The growth trial lasted for 8 weeks followed by a digestibility trial. At the end of 8 weeks lambs on ration 3 had gained significantly (p<0.10) more weight compared to those on rations 1 and 2 which maintained their body weight. The crude protein digestibility of the fourwing saltbush based ration was comparable with the other two treatments (71 vs 70 and 71%). However, the digestibility of dry matter (41%), acid detergent fibre (13%) and neutral detergent fibre (22%) of this ration was significantly lower (p<0.10) than the other two diets. The results suggest that lambs can be maintained on fourwing saltbush during winter without significant loss in body weight with 30% extra protein concentrate supplementation.