본 연구는 관상적 가치가 뛰어난 한반도 자생식물 너도개미 자리[Minuartia laricina (L.) Mattf.]의 산업화를 위한 대량 번 식 기술을 개발하기 위해 수행되었다. 종자 번식 실험에서는 2023년 8월 16일 형태적으로 완전히 성숙한 종자를 채종하여 사용하였으며, 종자의 내부 형태를 관찰한 결과 배가 완전히 발달하여 미숙배로 인한 형태적 휴면(MD)은 없음을 확인하였 다. 또한, 종자를 증류수에 침지시켜 수분 흡수율을 조사한 결과 수분흡수 24시간 후 약 66%의 수분 흡수율을 보여 불투수성 종피에 의한 물리적 휴면(PY)도 없음을 확인하였다. 실온 (22±2℃)에서 후숙처리(Dry after-ripening)를 0, 4, 21주 실 시 후 각각 4, 10, 15, 20, 25, 30℃로 설정된 기내 발아 실험을 진행하였다. 실험의 결과, 후숙 4주 처리 후 20℃에 치상한 종자 의 발아율이 약 76%로 가장 높았다. 후숙 처리를 하지 않은 종자는 12주 내 어떠한 온도 조건에서도 발아하지 않아 생리 적 휴면(PD)으로 판단되었다. 삽목 번식 실험에서는 줄기삽목 (Stem-cutting) 방식으로 진행하였고, 루톤 분제 처리가 발근 에 미치는 영향을 조사하였다. 루톤 분제를 처리하지 않은 처리 구는 발근율과 생존율이 100%로 나타났으며, 루톤 분제가 처리 된 삽수는 이들보다 발근율과 생존율이 통계적으로 유의하게 낮았다. 따라서 너도개미자리 종자는 생리적 휴면 종자로 분류 되며, 4주간의 후숙 처리가 휴면 타파에 효과적인 것으로 확인 되었다. 또한, 너도개미자리 삽목 번식 시 별도의 발근 촉진제 처리가 필요하지 않음을 확인하였다.
ㅊThis study aims to analyze fashion design cases using traditional elements based on the research and analysis of traditional folk cultural paper-cutting crafts in China, and to expand the area of fashion design using traditional elements by developing 3D digital fashion design. For herein, the techniques and characteristics of Chinese paper-cutting crafts were investigated. This survey facilitated an analysis of the formative characteristics of battery crafts in contemporary fashion design. As for the analysis case, the case of using battery crafts expressed in modern fashion for 10 years from 2010 to 2024 S/S was selected. The results are as follows. First, the typical characteristics of Chinese paper cutting technology—relief, micro-carved, combined with relief and micro-carved expressive techniques of engraving art effect— can be explored by analyzing contemporary fashion case collections through the perspective and trend of leading traditional culture. Second, in the traditional paper cutting process, most paper-cutting works are expressed in red, but white and black are mainly used in fashion, in addition to the active use of the five colors. Third, the characteristics of contemporary fashion patterns primarily utilize the paper-cutting process, incorporating elements such as plants, animals, and geometric patterns. Fourth, the utilization of paper cutting in 3D digital design offers time and economic benefits, allowing for quick adjustments to various design developments. In contemporary fashion, it is expected that the use of paper cutting can provide useful creativity and value for the inheritance and modernization of traditional culture.
Along This paper deals with research on firearm barrel processing and aims to improve firearm performance, accuracy, and machinability. The barrel is one of the key parts of a firearm and has a direct impact on shaping the trajectory of ammunition. In particular, durability and reliability are required due to the enormous heat generated as the bullet passes through. In this study, experiments were conducted under the processing conditions used in barrel processing to identify and analyze the characteristics. Various technologies and methods were investigated and analyzed. To achieve this, the cutting force generated during conventional barrel processing was measured to determine the level of stress on the material. In addition, we determined the suitability of tools and cutting conditions used in metal processing to identify conditions that can maximize productivity. This paper is expected to contribute to improving firearm performance by suggesting a plan to optimize processing conditions to the firearms manufacturing industry. Additionally, it can be used as a reference for barrel processing by other researchers.
Thermal cutting processes that can be applied to dismantling nuclear power plants include oxygen cutting, plasma cutting, and laser cutting. According to the global trend, research projects are being carried out in various countries to upgrade laser cutting, and many studies are also being conducted in Korea with plans to apply laser cutting processes when dismantling nuclear power plants. However, with the current technology level of the laser cutting process, the maximum thickness that can be cut is limited to 250 mm. Therefore, in this study, a laser-oxygen hybrid cutting process was implemented by adding a laser heat source to the oxygen cutting process that can cut carbon steel with a thickness of 250 mm or more (RV, beam, column, beam, etc.) when dismantling the nuclear power plant. This has the advantage of improving the cutting speed and reducing the cutting width Kerf compared to conventional oxygen cutting. In this research, the laser-oxygen hybrid cutting process consisted of laser cutting to which Raycus’ 8 kW Fiber Laser power source was applied and oxygen cutting to which hydrogen was applied with Fuel Gas. The oxygen torch was placed perpendicular to the test piece, and the laser head was irradiated by tilting 35° to 70°. The effects of cutting directions on quality and performance were studied, and cutting paths were selected by comparing cutting results. Thereafter, it was confirmed that there is an optimal laser output power according to the cutting thickness by studying the effect on the cutting surface quality by changing only the laser output power under the same cutting conditions. The results of this study are expected to be helpful in the remote cutting process using laser-oxygen hybrid cutting when dismantling domestic nuclear power plants in the future.
The purpose of using coolant in machining is both to increase a tool life and also to prevent product deformation and thus, stabilize the surface quality by lubricating and cooling the tool and the machining surface. However, a very small amount of cutting mist should be used because chlorine-based extreme pressure additives are used to generate environmental pollutants in the production process and cause occupational diseases of workers. In this study, medical titanium alloy (Ti-6Al-7Nb) was subjected to a processing experiment by selecting factors and levels affecting cutting power in the processing of the Aerosol Dry Lubrication (ADL) method using vegetable oil. The machining shape was a slot to sufficiently reflect the effect of the cutting depth. As for the measurement of cutting force, the trend of cutting characteristics was identified through complete factor analysis. The factors affecting the cutting force of ADL slot processing were identified using the reaction surface analysis method, and the characteristics of the cutting force according to the change in factor level were analyzed. As the cutting speed increased, the cutting force decreased and then increased again. The cutting force continued to increase as the feed speed increased. The increase in the cutting depth increased the cutting force more significantly than the increase in the cutting speed and the feed speed. Through the reaction surface analysis method, the regression equation for predicting cutting force was identified, and the optimal processing conditions were proposed. The cutting force was predicted from the secondary regression equation and compared with the experimental value.
SiAlON-based ceramics are a type of oxynitride ceramics, which can be used as cutting tools for heatresistant super alloys (HRSAs). These ceramics are derived from Si3N4 ceramics. SiAlON can be densified using gaspressure reactive sintering from mixtures of oxides and nitrides. In this study, we prepare an α-/β-SiAlON ceramic composite with a composition of Yb0.03Y0.10Si10.6Al1.4O1.0N15.0. The structure and mechanical/thermal properties of the densified SiAlON specimen are characterized and compared with those of a commercial SiAlON cutting tool. By observing the crystallographic structures and microstructures, the constituent phases of each SiAlON ceramic, such as α- SiAlON, β-SiAlON, and intergranular phases, are identified. By evaluating the mechanical and thermal properties, the contribution of the constituent phases to these properties is discussed as well.
This study was conducted to estimate the effect of different cutting lengths on fermentation characteristics and aerobic stability of whole crop rice (WCR) silage. The WCR was harvested at the yellow ripe stage (43.7%, DM), and then cut at 5 (R05), 10 (R10), and 20 cm (R20) of the theoretical length of cut with no cut WCR (R60). Each forage was ensiled into 20 L mini bucket silo (5 kg) for 150 days in quadruplicates. The cutting lengths were not affected the chemical compositions of WCR silage (p > 0.05). The pH (p < 0.001) and concentration of ammonia-N (p = 0.022) in WCR silage were increased linearly with the increase of cutting length. The concentration of lactate had quadratic effect (p = 0.007), which was highest in R20 silage (p < 0.05). The concentration of acetate was increased linearly (p = 0.014), but the concentration of butyrate was decreased linearly (p = 0.033). The lactic acid bacteria count was decreased linearly (p = 0.017), and yeast count had quadratic effect (p = 0.009), which was the highest in R20 silage (p < 0.05). Aerobic stability had strong quadratic effect (p < 0.001), which was the highest in R20 silage (p < 0.05). In conclusion, R60 silage had highest pH by a linear increase of ammonia-N concentration and led to low aerobic stability. While R20 silage had the lowest pH by high lactate concentration and led to high aerobic stability.
진정한 의미에서의 민간예술작품에서 구현하는 것은 겉면에 표출된 화려한 표상할 뿐만 아니라 그 내면을 탐구하는 것, 더욱 이런 예술 풍격을 단조해 낸 불굴의 민족의식과 정감이다. 예로부터 사회의 발전과 계급 분화로 원시 예술의 변천을 거쳐 분리되어 형성된 문인예술, 궁정예술, 종교예술, 민간예술에 이르기까지 이러한 다른 관념을 기반으로 한 예술 문화 종류가 역사의 흐름 속에서 갈등하고 또 끊임없이 서로 연계하며 기반으로 하고 모순, 연계와 융합에서 하나의 완전한 민족 문화를 육성하였다. 오늘에 이르기까지 민간예술문화에서의 순수한 예술 신념은 여전히 줄곧 이른바 고상하고 우아한 예술 문화에 대해 확고한 기초적 역할을 하고있다. 수암만족 민간 전지(剪紙)는 동북 백산흑수사이에 만족 노동 인민이 창조한 역사적 예술 문화의 완벽한 결정체일 뿐만아니라 또한 수암의 전통적 만족 민간 예술 특유한 민족 예술문화 표식이고 동북 지역의 만족 의향 및 옥도 특색의 전통 민간예술의 걸출한 대표이다. 이것은 동북 만족 인민의 지혜의 예술을 포함하고 있으며 중요한 역사적 가치와 문화적 가치가 있을 뿐만 아니라 또한 중요한 예술적 가치와 과학적 가치를 지니고 있으며 전통문화의 결정체이자 화하문명의 보물이다. 지금은 어떤 의미에서 이미 문화브랜드로 된 민간 전지예술이 점차 문화의 수요품으로 되고 있다. 특유의 가치와 방식으로 문화가 널리 전파되는 또 다른 경로로 되고 있다. 그러나 북방 만족 전지를 놓고 말할 때 기나긴 과정에서 아주 많은 문제도 나타났다. 이를테면 제작 형식과 예술 풍격의 혼동, 관련 문화자료내용의 귀납 정리와 발전 전승 등이다. 본 논문은 북방 만족 문화의 대표 특징을 지닌 수암만족 전지를 연구 대상으로 지역 역사, 문화 신앙 등등 방면에 대해 중국 북방 만족 종이 오림이 형성된 근원성 원인을 심도 있게 분석하였다. 이와 동시에 종이 오림 작품이 드러낸 예술 상태에 있어서 다른 지역의 동류 작품들과 전체적 및 개별적 비교를 하여 예술풍격상의 지역문화 차이를 분명히했다. 또 현재를 결부시켜 전지 예술이 사람들에게 대한 의의를 서술하고 전통문화를 발전시키고 전승할 것을 호소했다.
The Carbon Fiber Reinforced Plastic(CFRP) is used in many industrial areas owing to its excellent specific strength. In order to be utilized for machine parts, it is needed to have the hole drilling machining that presents the excellent surface. For the excellent hole machining of CFRP, this study evaluated the cutting force and remaining burr in accordance with changes in temperature by cooling down the temperature of the machining part. It could be used for other machining of composite materials produced by laminating fabric.
The A182 steel is used in the steam pressure regulator of power plant valves. Since the part is operated under high temperature and high pressure conditions, it is necessary to study the machining characteristics. In this study, EDS analysis of the tool wear shape according to the cutting condition of A182 steel was performed. The A182 steel is identified as a steel belonging to the hardest cutting material and will be used to derive the optimum cutting condition.
Currently, the cutting oil supply device is not equipped to cool the cutting oil. Therefore, additional cooling device should be connected to cool the cutting oil. This has the disadvantage of increasing the size of the device and reducing its cooling capability. To overcome these shortcomings, cooling coils are applied to the outside of the cutting oil filtering device to develop a heat exchanger filter for simultaneous coolant filtering and cooling to improve the compactness of the cutting oil supply device and cooling capability of the cutting oil. For the development of heat exchanger filter, flow and heat transfer analysis were performed. Due to the small heat transfer area of 10 cooling coils, less heat exchange occurred. In the 20 cooling coils, the coolant cooling coils prevented smooth flow of the cooling oil in the heat exchanger filter. The cooling efficiency of the 15 cooling coils were best, and the cooling temperature decreased non-linearly as the supply flow rate of the cutting oil increased.
Among various materials, FCD500 is widely used in various fields of automobile components as it allows mass production through casting and its mechanical property is excellent. However, there are many problems in industry due to the fact that despite the wide use of FCD500, the researches about manufacture property of FCD500 are insufficient. Thus, this study conducted research on cutting manufacture property of FCD500, which is the most common manufacture method of FCD500 to suggest optimized tool and cutting condition. To achieve this, the study examined the change in cutting property based on tool material based on the most commonly used CVD(Chemical Vapor Deposition) coating tool and CBN tool, and examined the changes in cutting property by the form of CVD coating tool. The study measured cutting force, surface roughness of material after cutting, and amount of tool wear to examine the cutting property. The study gave variation in cutting speed of 280m/min and 500m/min, and fixed the feed rate and cutting depth for cutting condition to evaluate the changes by cutting speed.