• Asian-Australasian Journal of Animal Sciences
• /
• 제33권7호
• /
• pp.1209-1216
• /
• 2020

Objective: The present study aimed to evaluate the performance of odor abatement by using two different ventilation-biofilter systems with recycled stablized swine wastewater. Methods: The performance of odor removal efficiency was evaluated using two different ventilation-biofilter-recycled wastewater arrangements. A recirculating air-flow ventilation system connected to a vertical biofilter (M1) and a plug-flow ventilation system connected to a horizontal biofilter (M2) were installed. Water dripping over the surface of the biofilter was recycled at a flow rate of 0.83 L/h in summer and 0.58 L/h in winter to reduce odorous compounds and particulate matter (PM). The experiments were performed for 64 days with M1 and M2 to investigate how these two ventilation-biofilter systems influenced the reduction of odor compounds in the model houses. Odorous compounds, NH₃ and volatile organic compounds (VOCs) were analyzed, and microclimatic variables such as temperature, humidity, and PM were monitored. Results: Ammonia concentration inside M1 was about 41% higher on average than that in M2. PM and total suspended particles (TSPs) inside M1 were about 62.2% and 69.9%, respectively, higher than those in M2. TSPs in the model house were positively correlated with the concentration of NH₃ and VOCs. Conclusion: M2 emitted lower concentration of odorous compounds than M1. Moreover, M2 could maintain the optimum temperature condition for a swine house during the cooler season. The plug-flow ventilation-horizontal biofilter system could be used for pig houses to minimize air pollution produced by swine farming activities and maintain optimum microclimate conditions for pigs.

• 한국수정란이식학회지
• /
• 제27권1호
• /
• pp.37-43
• /
• 2012

This study evaluated a method of sorting X and Y chromosomes based on size using the forward angle light scatter related refractive index (FSC) of a flow cytometer. Hanwoo bulls sperm were separated to X and Y chromosomes by the parameters of FSC or Hoechst 33342 intensity. As a result, using monitor program linked flow cytometry during sorting processing, the purities were $97{\pm}0.57$ or $96{\pm}0.67%$ for the X-fraction and $96{\pm}0.33$ or $97{\pm}1.33%$ for the Y-fraction in the two sperm sorting methods. There were no differences in the X and Y ratios (X and Y %) between the sperm sorting methods based on FSC or DNA content. The proportions of female and male embryos used for in vitro fertilization and development were $66.03{\pm}3.31$ or $69.37{\pm}1.41%$, and $70.56{\pm}2.42$ or $56.11{\pm}3.09%$ when sperm were processed using the sex sorting method by FSC or Hoechst 33342. In conclusion, further study is needed to determine the optimum procedure and improve the nozzle to enhancing sorting accuracy or efficiency. Also, the findings of this study do not negate the possibility that the difference method of sperm sorting cannot use a UV laser beam.

• 한국엔터테인먼트산업학회논문지
• /
• 제14권8호
• /
• pp.131-140
• /
• 2020

이 글은 사회문화적 의미를 지향하는 퍼포먼스로서의 영화연기라는 방법론을 최민식의 연기에 적용하고자 하였다. 구체적으로, 영화배우 최민식의 인터뷰 구술에 언급된 신체, 얼굴, 오디오, 연출과의 관계, 영화기술에 대한 태도 등을 분석하였다. 결론적으로, 최민식의 연기는 메소드 액팅으로만 규정할 수 없고, 스타니슬랍스키, 스트라스버그, 메이어홀드, 브레히트, 그로토프스키 등의 전형적이거나 전위적인 연기론을 함축하거나 통합하며, 무엇보다 크라카우어가 제시한 움직임으로 재현되는 생명의 흐름을 명시하는 표상이다. 최민식 스스로가 강조하는 연민의 정서가 생명의 흐름을 재현하는 영화의 본질과 맞닿아 있고, 그것은 어떤 목적을 갖는 의도된 스크린 퍼포먼스로 확장된다. 연민과 생명의 흐름으로 압축할 수 있는 스크린 퍼포먼스는 최민식의 다양한 페르소나로 표출된다. 선악을 넘나드는 그의 페르소나는 한국사회의 현재를 반영한다.

• 한국가정과교육학회지
• /
• 제24권1호
• /
• pp.61-71
• /
• 2012

이 연구는 초등학교 5,6학년을 대상으로 2007 개정 실과교육과정의 가정생활 영역을 활용한 STEAM 교육프로그램을 개발하고 그 효과를 검증하는데 그 목적이 있다. 연구방법은 2007 개정 실과교육과정의 7개 가정생활 영역 중 STEAM을 적용하기 적합한 주제를 하나씩 선정하여 총 10차시의 교사용 교수-학습 과정안과 학생용 학습지를 개발하였다. 대구광역시 소재의 A초등학교 5학년 한 학급 21명을 대상으로 프로그램을 적용한 후 실과에 대한 태도와 학습몰입의 변화를 분석하였다. 연구의 결론은 다음과 같다. 첫째, 초등학교 실과 가정생활 영역은 STEAM을 적용하기에 적절한 주제로 이루어져 있으며, 이를 바탕으로 7개 주제의 10차시 STEAM 교육프로그램이 개발되었다. 개발된 프로그램은 교사용 교수-학습 과정안과 학생용 학습지로 구성되어 있으며, 교사용 교수-학습 과정안에는 선택적으로 활용할 수 있는 다양한 STEAM 교육 요소를 제시하였다. 둘째, 개발한 실과 가정생활 영역을 활용한 STEAM 교육프로그램은 초등학생의 실과에 대한 태도를 향상시키는데 효과적이다. 셋째, 개발한 실과 가정생활 영역을 활용한 STEAM 교육프로그램은 초등학생의 학습몰입 수준을 향상시키는데 효과적이다.

• JSTS:Journal of Semiconductor Technology and Science
• /
• 제7권3호
• /
• pp.140-150
• /
• 2007

A simple, label-free microfluidic cell purification method is presented for separation of cancer cells by exploiting difference in cell adhesion. To maximize the adhesion difference, three types of polymeric nanostructures (50nm pillars, 50nm perpendicular and 50nm parallel lines with respect to the direction of flow) were fabricated using UV-assisted capillary moulding and included inside a polydimethylsiloxane (PDMS) microfluidic channel bonded onto glass substrate. The adhesion force of human breast epithelial cells (MCF10A) and human breast carcinoma (MCF7) was measured independently by injecting each cell line into the microfluidic device followed by culture for a period of time (e.g., one, two, and three hours). Then, the cells bound to the floor of a microfluidic channel were detached by increasing the flow rate of medium in a stepwise fashion. It was found that the adhesion force of MCF10A was always higher than that of MCF cells regardless of culture time and surface nanotopography at all flow rates, resulting in a label-free detection and separation of cancer cells. For the cell types used in our study, the optimum separation was found for 2 hours culture on 50nm parallel line pattern followed by flow-induced detachment at a flow rate of $300{\mu}l/min$.

• Reproductive and Developmental Biology
• /
• 제36권1호
• /
• pp.1-6
• /
• 2012

This study evaluated a sexed sperm ability to produce embryos by flow cytometer. Hanwoo bulls sperm were separated to X and Y sperm via Hoechst 33342 stained with near UV laser or performed the pre-sorted without near UV laser beam in flow cytometry. Pre-sorted sperm had significantly higher viability ($84{\pm}1.15%$, $p$<0.05) compared to other sorted groups in frozen-thawed semen. For fresh semen, pre-sorted sperm had the higher viability ($79{\pm}3%$, $p$<0.05) than those of the X and Y sperm ($44.7{\pm}1.67$ and $41.7{\pm}1.2%$) separated by differences of DNA content. On the other hand, pre-sorted and X sperm sorted according to differences in DNA content had significantly higher viabilities ($24.3{\pm}1.2$ and $25.7{\pm}0.9%$, $p$<0.05) compared to that of the sorted Y sperm ($13.7{\pm}1.2%$) in the hypoosmotic swelling test. The proportion acrosome reaction in the sorted X sperm was higher ($55.0{\pm}1.7$ and $45.0{\pm}1.5%$) than those of the sorted Y-sperm ($32.3{\pm}0.9%$, $p$<0.05). However, the sperm morphologies of the sorted groups were not significantly differences. In conclusion, the sex-sorting procedure by flow cytometry affected some characteristics of Hanwoo sperm. Further study is needed to determine the optimal procedures to enhance male and female embryos and sorting accuracy.

• 한국산학기술학회논문지
• /
• 제21권4호
• /
• pp.558-567
• /
• 2020

본 연구는 항공기 운용 중 발생하는 구조 결함의 원인을 분석하기 위해 연료흐름분배기 장착 구조물의 결함특성을 확인하고자 한다. 일반적으로 항공기 운용 중 발생하는 체계 진동과 구성품 단일 진동에 의해 구조 결함이 야기된다. 결함을 정의하고 설계 및 운용 분석으로 이어지는 과정을 통해 원인 규명 방법을 제시하고자 한다. 연료흐름분배기는 급격한 유량의 증가로 인한 압력의 변화로 발생되는 진동에 의해 지지구조의 결함이 발생되었다. 지지구조에 발생하는 하중 특성 및 파단면 분석을 통해 초기 균열이 반복하중으로 인해 피로균열이 발생하였다. 연료흐름분배기 지지구조 결함은 항공기 운용분석 결과 기종별 기동 및 비행시간은 균열과 직접적인 상관관계가 적고, 후기연소(A/B) 사용과 관련이 있다. 결함에 대한 개선을 위해 연료흐름분배기 하부 장착 Bracket의 균열 부위에 정적 및 수명해석을 통해 구조 보강형상을 확정하였다. 보강에 대한 분석 결과 구조 강도 최소 마진이 +0.15로 구조 건전성을 확인하였고, 구조 수명 분석결과 해당 부위에 응력이 15Ksi 이하로 작용하였으며 피로 수명이 7,700 Cycle 이상임을 확인하였다.

• International Journal of Fluid Machinery and Systems
• /
• 제2권4호
• /
• pp.449-455
• /
• 2009

A reversible axial flow fan called jet fan has been widely used for longitudinal ventilation in road tunnels to secure a safe and comfortable environment cost-effectively. As shifting the flow direction is usually made by only switching the rotational direction of an electric motor due to heavy duty, rotor blades having identical aerodynamic performance for bidirectional flow should be necessary. However, such aerodynamically desirable blades haven't been developed sufficiently, since most of the related studies have been done from the viewpoint of unidirectional flow. In the present paper, we demonstrate a method to profile the blade section suitable for bidirectional flow, which is validated by studying the aerodynamic performances of rotor blades of a two-stage jet fan experimentally and numerically.

• 유체기계공업학회:학술대회논문집
• /
• 유체기계공업학회 2002년도 유체기계 연구개발 발표회 논문집
• /
• pp.419-424
• /
• 2002

The HANARO, a multi-purpose research reactor of 30 MWth open-tank-in-pool type, has been under normal operation since its initial criticality In February, 1995. Many experiments should be safely performed to activate the utilization of the HANARO. A flow simulation facility is being developed for the endurance test of reactivity control units for extended life times and the verification of structural integrity of those experimental facilities prior to loading in the HANARO. This test facility is composed of three major parts; a half-core structure assembly, flow circulation system and support system. The flow circulation system is composed of a circulation pump, a core flow pipe, a core bypass flow pipe and instruments. The system is to be filled with de-mineralized water and the flow should be met the design flow to simulate similar flow characteristics in the core channel of the half-core test facility to the HANARO. This paper, therefore, describes an analytical analysis to study the flow behavior of the system. The computational flow analysis has been performed for the verification of system pressure variation through the three-dimensional analysis program with standard k-$\epsilon$ turbulence model and for the verification of the structural piping integrity through the finite element method. The results of the analysis are satisfied the design requirements and structural piping integrity of flow circulation system.

• 한국자동차공학회논문집
• /
• 제6권5호
• /
• pp.55-65
• /
• 1998

A numerical and experimental study of three-dimensional steady incompressible non-reacting flow inside various dual-monolith catalytic converters has been conducted for achievement of performance improvement, reduction of light-off time and longer service life by improving the flow uniformity within the monolith. In this study, the effects of curvature of inlet exhaust pipe and monolith brick length on the flow uniformity and pressure drop within monolith were numerically investigated. The computations are confirmed by measurements of steady flow. The agreement between computations and experiment was relatively good. The result of this study shows that curvature of inlet exhaust pipe and monolith brick length gave a great effect on the flow uniformity and the shorter the brick length, the lower flow uniformity and the less pressure drop.