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        검색결과 441

        141.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Hay-making is one of the most common forage preservation practices in livestock operations. The objective of hay-making is to minimize nutrient loss by shortening field drying time. Measuring the impacts of cutting height of forage crop is necessary to optimize hay production balancing yield and quality, in order to obtain substantial biomass increase through harvest of regrowth. This experiment was conducted to investigate the impact of cutting height of rye (Secale cereale L.) on drying rate and hay quality. Heading stage rye was harvested at 8cm or 15cm stubble heights. Hay was daily tedded at 09:00 and sampled at 09:00, 13:00 and 17:00 to determine moisture content (MC). After two month of preservation, CP (crude protein), ADF (acid detergent fiber), NDF (neutral detergent fiber), IVDMD (in vitro dry matter disappearance), TDN (total digestible nutrient), RFV (relative feed value), DM (dry matter) loss, visual scores and total fungi count were determined for estimation of hay quality. Cutting height at 15cm could enhance the drying rate and CP content (p<0.05), but also increases DM loss (p<0.05) compared to cutting at 8cm. Cutting heights did not affect ADF, NDF, IVDMD, TDN and RFV value (p>0.05). Visual scores of rye hays cutting at 8cm and 15cm, ranged from 83 to 85. Cutting at 8cm tended to maintain higher core bale temperature and fungal count than cutting at 15cm during preservation, but there was no significant difference.
        4,000원
        143.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to identify milling characteristics depending on the number of a cutting roller’s air vent and blowing velocity to remove rice bran by the cutting type milling machine which can minimize the conventional milling process. The level of whiteness was found to be 38±0.5 in all the conditions, showing consistent whiteness levels during milling. The rice temperatures turned out to be 15.4 and 14.6oC which were rather low-level under the conditions of the cutting roller with 3 vents and blowing velocities of 35 and 40 m/s respectively. Cracked rice ratio was 2.13% under the conditions of the cutting roller with 3 vents and a blowing velocity of 35 m/s. Broken rice ratio showed the range of 0.762-0.869%, reflecting a low level. Turbidity after milling was decreased, as blowing velocity became faster. Energy consumption for milled rice production was decreased, as blowing velocity became faster. The optimum milling condition for cutting type milling machine depending on air vent number of cutting roller and blowing velocity was found to be 3 vents and 35 m/s.
        4,000원
        144.
        2017.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study aimed to identify milling characteristics depending on the number of a cutting roller’s air vent and blowing velocity to remove rice bran by the cutting type milling machine which can minimize the conventional milling process. The level of whiteness was found to be 38±0.5 in all the conditions, showing consistent whiteness levels during milling. The rice temperatures turned out to be 15.4 and 14.6oC which were rather low-level under the conditions of the cutting roller with 3 vents and blowing velocities of 35 and 40 m/s respectively. Cracked rice ratio was 2.13% under the conditions of the cutting roller with 3 vents and a blowing velocity of 35 m/s. Broken rice ratio showed the range of 0.762-0.869%, reflecting a low level. Turbidity after milling was decreased, as blowing velocity became faster. Energy consumption for milled rice production was decreased, as blowing velocity became faster. The optimum milling condition for cutting type milling machine depending on air vent number of cutting roller and blowing velocity was found to be 3 vents and 35 m/s.
        4,000원
        146.
        2017.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The study is the development of stone processing machines for larger blocks of stone for more than 2 meters. The wire saw were replaced by the cutting of existing prototypes and employed as a new form of cutting tools equipped with industrial diamonds. In addition, a turn table was developed to enable the milling of large blocks of stone allowing them to spin. On the other hand, large processing machinery has been imported and used mostly by Chinese machinery and has caused many inconveniences in managing and using equipment. Therefore, it is difficult for domestic production products to remain unstable, thus maintaining the nation`s crumbling granite industry. As a result, it is uncomfortable to find domestic products, but it is difficult to maintain the domestic stone industry. Therefore, we look forward to the revitalization of the domestic stone industry through this development.
        4,000원
        148.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        There is a growing demand for improving the welding quality by reducing the machining error and improving the quality of the machined surface in the beveling for the improvement of the welding groove of the thick plate. For this purpose, it is necessary to develop an automatic beveling machine that adopts a cutting method that replaces the conventional oxygen flame cutting method. In this study, the cutting characteristics according to the machining conditions were evaluated during the face milling applied to the thick plate welding groove. We measured and evaluated cutting force for the machining conditions such as cutting depth, feed rate, chamfer angle, workpiece material, and material of the tool. We expect that this study is used as basic data for designing the stiffness of the spindle, the strength of the fixture and the power of the spindle and the feeding device when designing the automatic beveling machine.
        4,000원
        149.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to determine the effect of rainfall after cutting on nutritive value of Italian ryegrass (Lolium multiflorum) hay. Fresh Italian ryegrass was treated with 3 days natural rainfall (56.5, 14.0 and 1.6 mm) after cutting without tedding. Rainfall effect on Italian ryegrass quality was evaluated based on Neutral detergent fiber (NDF) and acid detergent fiber (ADF), crude protein (CP), crude fat (CF), crude ash (CA) and non-fiber carbohydrate (NFC). The quality of Italian ryegrass was decreased with extending raining days. The content of neutral detergent fiber (NDF) was increased from 0.4 to 4.7% by 1 day advancement in raining. CF content was decreased from 8.1 to 32.8%. CP and CA contents did not change, but NFC content was decreased from 0.5 to 8.4%. The quality damage by the number of raining days after cutting Italian ryegrass was the lowest on the first day from exposure to rain.
        4,000원
        150.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Forest clear-cutting operations influence biodiversity through habitat changes and food resource availability for inhabitant species. This study examined the effects of clear-cutting on forest arthropod communities. Arthropods were collected from two different forest treatment areas (clear-cut and control) in summer and autumn. In each treatment area, arthropods were sampled from both crown and ground surfaces using sweeping and pitfall trap methods, respectively. Then, the taxonomic order of the collected arthropod specimens was easily identified. Results indicate that arthropod abundance and number of taxa present were higher at ground surface than at crown levels in both clear-cut and control areas. At crown level, more homopteran species were present in clear-cut areas than in control areas in summer. At ground surface, populations of Isopoda and Opiliones were higher in control areas than in clear-cut areas, whereas numbers of Araneae, Orthoptera, and Hymenoptera were greater in clear-cut areas. Cluster analysis and principal component analysis showed distinct differences between clear-cut and control communities at crown level in summer and at ground surface in autumn. Thus, our results indicate that clear-cutting significantly influences arthropod communities, and higher taxa are valuable for conducting rapid biological assessments of ecosystem disturbances.
        4,000원
        151.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A study was conducted to evaluate the effects of auxin, cytokinin, and their combined application to hasten their propagation using leaf cuttings. Different hormone levels were evaluated on two Echeveria species (E. subsessilis and E. runyonii). Three levels of auxin as represented by the use of indole-3-butyric acid (IBA) (0, 100, and 500 ppm), three cytokinin levels as represented by Kinetin (Ki) (0, 100, and 200 ppm) and their combination were applied and observed for 8 weeks. The use of 100 ppm IBA resulted in the highest shoot height, diameter, and rooting and shooting rate. Using 500 ppm IBA led the roots to develop the earliest but both species also had the highest mortality. The application of 100 ppm Ki significantly affected the majority of leaf cuttings of E. runyonnii which exhibited the highest and thickest shoots, and the number of leaves. The application of 100 ppm IBA and 100 ppm Ki is recommended to obtain increased shoot growth and development for leaf cuttings. In the case of single hormone use, the application of 100 ppm IBA may be preferable. The combination of auxin and cytokinin significantly stimulated the hastening of production of succulents using leaf cuttings.
        4,000원
        152.
        2016.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Growth and development of succulents were studied in response to two leaf cutting types, the tip and base, using four Echeveria species (E. ‘A Grimm One’, E. ‘Momorato’, E. pulvinata ‘Frosty’, and E. pulidonis) and the planting position, either upright and faced-downward, using Graptoveria optalina. The shoot diameter (mm), height (mm), and number of leaves were significantly affected by the leaf cutting type. Results revealed that the shoot diameter of buds from base leaves were significantly larger by 4 - 9 times than those of buds from tip leaves. Shoot height of buds from tip leaves either not developed or reached a maximum of 2.29 mm while buds from base leaves had an average height of 11.61 mm from E. ‘Mamorato’. Using base leaves allowed to obtain roots and leaves for all selected succulent species after 60 days from planting. Regarding planting position, upright planted and downward-facing plants showed significant differences: buds from upright planting showed taller shoots, greater number of leaves which in turn gave higher visual quality rating and superior color reading using Hunter’s Cielab compared with buds in downward-facing planting position. Planting succulents in an upright position led to well-formed shoots and roots which had a high-quality rating and color evaluation compared with faced-downward planting producing etiolated and abnormal grown shoots. Based on these findings, we suggest that the use of base leaf cuttings and an upright planting position provides a rapid vegetative propagation method for selected succulent varieties.
        4,000원
        153.
        2016.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서 개발된 자동천공기는 콩의 재식밀도를 고려한 비닐 천공능력이 작업주행속도 0.18- 0.28m/s 조건에서 콩의 주간거리 0.20m, 0.25m, 0.30m에 대해 각각 320-500m2/h, 260-400m2/h, 210-330m2/h의 범위로 나타났다. 천공율은 칼날과 지면간 30mm 거리에서 비닐이 100% 천공되었으 며, 50mm 거리에서 원형칼날 16.7-25.2%, 사각칼날 33.0-42.3%, 육각칼날 54.5-100.0% 범위에서 천공되었다. 또한, 육각칼날 60°에서 비닐 절단면이 매끄럽고 부드러워 절단품질이 가장 우수하였다.
        4,000원
        154.
        2016.10 구독 인증기관 무료, 개인회원 유료
        본 연구개발은 2m 이상 대형 석재에 대한 가공기계 개발에 관한 것으로서, 종전에 강철재 원형톱을 회전시켜 석재를 절단하던 방식을 개선하여 와이어에 공업용 다이아몬드를 장착한 와이어 쏘우를 절단도 구로 채용하였다. 또한 부수장치로 거대 석재를 전후좌우 및 회전이 가능하여 다각도 가공이 가능하도록 턴테이블식 공작물 베드를 설계 및 개발하였다. 한편 대형 석재 가공기계는 대부분 중국산 기계가 수입되어 사용되어지고 있으며, 이로 인한 장비 관리 및 사용에 있어서 여러 가지 불편한 점들이 산재해 있으나 국내 생산 제품이 전무하여 불편함을 감수하면서 어렵게 국내 석재산업을 유지하여 오고 있는 실정이다. 따라서 본 개발을 통해서 국내 석재산업의 활성화를 기대해 본다.
        3,000원
        155.
        2016.10 구독 인증기관·개인회원 무료
        The consumption of pre-treated vegetables (including fresh-cut vegetables) has been significantly increased because of their ease of use for cooking. Vegetable cutting machine has been widely utilized for producing fresh-cut vegetables or agricultural products with different sizes; however, its design standard is not specifically established depending on types of agricultural products. Therefore, this study was conducted to determine mechanical properties (compressive and shear force) of targeted agricultural products (radish, carrot, squash, cucumber, shiitake mushroom and sweet potato) for developing multipurpose vegetable cutting machine. According to ASAE standard (s368.3), compressive and shear force of targeted agricultural products were measured by using custom built UTM (universal testing machine). Shape type of samples and speed ranges (5~15 mm/min) of loading rate on bioyield and shear points were varied by targeted agricultural products. The range of averaged bioyield points of targeted agricultural products were between 7.89 and 146.98 N. On the other hands, their averaged shear points were from 22.50 to 53.47 N. Results clearly showed that the bioyield and shear points of targeted agricultural products were thoroughly affected by their components. As accumulating compressive and shear points of agricultural products, it can be technical feasible to establish the design standard and control mechanism of multipurpose vegetable cutting machine.
        156.
        2016.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 실험은 종자 가격이 비싼 여주를 삽목하여 증식하고자 할 때 적절한 줄기 절단위치와 삽목상내 온도를 구명하기 위하여 실험하였다. 시험품종 ‘NS454’(NS)와 ‘드레곤’(DR) 품종을 대상으로 삽수 절단 위치를 3번째 잎의 마디를 절단한 처리(I) 와 3번째와 4번째 잎의 중간없이 발근이 되지 않았다. 뿌리의 개체당 발근수는 DR 품종의 경우, 28oC 처리구는 마디 중간지점을 절단한 처리구에서 5.3개로 처리구중에서 가장 많았고 마디를 절단한 처리구는 2.7개이었다. 따라서 여주의 삽목시 절단위치는 마디부위를 절단하거나 마디 중간지점을 절단해도 되지만 마디 중간지점을 절단하는 것이 생존율을 높일 수 있을 것으로 사료되고, 또한 삽목상내 기온을 28oC 정도를 유지해 주는 것이 바람직할 것으로 판단된다.
        4,000원
        157.
        2016.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigates on the tuning stainless steel(STS630) to understand for groove cutting characteristics. For this purpose, we observed the cutting force according to feed rate and cutting speed variation and performed the computational analysis due to groove cutting depth. In groove cutting of stainless steel, there were principal force, feed force and radial force by arranging the highest cutting force in order. In case of wall thicknesses of 0.3mm and 0.5mm at groove cutting, principal force increases according to the increase of feed rate but it is not related to cutting speed. We found the unstable region of cutting force that is caused to the friction resistance of cutting tool and elastic deformation of groove wall. In computational analysis, we confirmed that the more feed rate increases, the more strain increases around the tooth root.
        4,000원
        158.
        2016.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, we conducted an interrupted cutting SM20C with lathe and uncoated carbite tool, determined the relationship between Cutting Forces(principal, radial, feed force) by correlation analysis, and predicted the optimum cutting conditions by multiple regression analysis. The result were as follow. : From the correlation analysis, the increase of cutting speed and depth of cut reduces the principal force and radial force. the increase of cutting speed, depth of cut and feed rate will increase the feed force. From multi-regression analysis, we extracted regression equation and the coefficient of determination (R2) was 0.638, 0.692, 0.536 at principal, radial and feed force . It means that the regression equation is not high accuracy. However, it is predictable that the tendency of the forces action the interrupted cutting.
        4,000원
        160.
        2016.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, we develop mobile stone cutting machine containing the cut and frame, the frame vertically conveying part and the cutting upper and lower conveying part. The cutting part has saw and it cuts stone. The frame has cutting part, vertically conveying part of can slide on main frame and the main frame has horizontal conveying part. It can move cutting part. Mobile stone cutting machine is composed of two parts. The frame vertically conveying part is installed vehicle and it conveying frame in the vertical direction. The cutting vertically conveying part is installed frame. It can transfer cutting part in the vertical direction.
        4,000원