• Title/Summary/Keyword: 가공정도

Search Result 1,065, Processing Time 0.03 seconds

Mechanical Alignment of Hull Mounted Phased Array Radar on the Separated Mast (분리된 마스트에 설치되는 선체고정 위상 배열 레이더의 기계적 정렬)

  • Seo, Hyeong-Pil;Kim, Dae-Han;Kim, Joon-Woo;Lee, Kyung-Jin;Cho, Kyu-Lyong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.20 no.9
    • /
    • pp.465-473
    • /
    • 2019
  • This paper is meaningful as the first case where a 4 - sided hull-fixed phased array radar was installed on a mast separated from Korea and the alignment was verified. The mechanical alignment method was studied for accurately mounting two separate masts for naval ships and the 3D scanner for alignment. Hull-fixed phased array radar uses very high frequency, so the short wavelength can cause a phase difference of the device due to the small positional error. Since the array antenna is fixed with the hull, it has higher accuracy control than the rotary radar for 4 array surfaces. The study describes a method of checking the flatness of two radar masts manufactured at a factory, a method of aligning masts in a shipyard, and a method of aligning four array pad mounting surfaces. As a tool for this, a 3D laser scanner and a software-based method for comparing survey results with 3D CAD are used. This paper is meaningful as the first example of installing a four-sided hull-fixed phased array radar on a separate mast from a Korean naval ship and deriving a mechanical alignment method.

The effect of nitrogen contents in media and cultivation temperature on freshness prolongation in Pleurotus eryngii (큰느타리버섯 배지 질소함량 및 온도조건별 선도연장효과)

  • Moon, Ji-Young;Kim, Jeong-Han;Choi, Jong-In;Jeong, Gu-Hyun;Gwon, Hee-Min;Ha, Tai-Moon
    • Journal of Mushroom
    • /
    • v.18 no.4
    • /
    • pp.339-343
    • /
    • 2020
  • This study aimed to optimize total nitrogen (TN) content in the medium and the growth temperature to improve the shelf life of Pleurotus eryngii Keneutari No. 2. We investigated the growth characteristics and changes in the O2/CO2 content in polypropylene film and performed sensory evaluations during cold storage under 1.5%, 1.8%, 2.1%, and 2.4% TN and at temperatures of 9℃, 12℃, and 15℃. The diameter and weight of the fruit bodies tended to increase with increasing nitrogen content, regardless of the growth temperature, and the highest weight per bottle (149.5 g) was obtained at 12℃ and 2.4% TN. Regardless of the nitrogen content, leaf color deepened with decreasing temperature. The gas concentration in the film, which changes depending on storage time, was maintained for the longest period at 9℃ and 2.1% TN. The sensory evaluation revealed no difference between the different nitrogen conditions tested, and the odor, discoloration, and decay were similar at 15℃ and 9℃ until day 28 of storage.

Assessment of Contribution of Climate and Soil Factors on Alfalfa Yield by Yield Prediction Model (수량예측모델을 통한 Alfalfa 수량에 영향을 미치는 기후요인 및 토양요인의 기여도 평가)

  • Kim, Ji Yung;Kim, Moon Ju;Jo, Hyun Wook;Lee, Bae Hun;Jo, Mu Hwan;Kim, Byong Wan;Sung, Kyung Il
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.41 no.1
    • /
    • pp.47-55
    • /
    • 2021
  • The objective of this study was to access the effect of climate and soil factors on alfalfa dry matter yield (DMY) by the contribution through constructing the yield prediction model in a general linear model considering climate and soil physical variables. The processes of constructing the yield prediction model for alfalfa was performed in sequence of data collection of alfalfa yield, meteorological and soil, preparation, statistical analysis, and model construction. The alfalfa yield prediction model used a multiple regression analysis to select the climate variables which are quantitative data and a general linear model considering the selected climate variables and soil physical variables which are qualitative data. As a result, the growth degree days(GDD) and growing days(GD), and the clay content(CC) were selected as the climate and soil physical variables that affect alfalfa DMY, respectively. The contributions of climate and soil factors affecting alfalfa DMY were 32% (GDD, 21%, GD 11%) and 63%, respectively. Therefore, this study indicates that the soil factor more contributes to alfalfa DMY than climate factor. However, for examming the correct contribution, the factors such as other climate and soil factors, and the cultivation technology factors which were not treated in this study should be considered as a factor in the model for future study.

Development of an abnormal road object recognition model based on deep learning (딥러닝 기반 불량노면 객체 인식 모델 개발)

  • Choi, Mi-Hyeong;Woo, Je-Seung;Hong, Sun-Gi;Park, Jun-Mo
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.22 no.4
    • /
    • pp.149-155
    • /
    • 2021
  • In this study, we intend to develop a defective road surface object recognition model that automatically detects road surface defects that restrict the movement of the transportation handicapped using electric mobile devices with deep learning. For this purpose, road surface information was collected from the pedestrian and running routes where the electric mobility aid device is expected to move in five areas within the city of Busan. For data, images were collected by dividing the road surface and surroundings into objects constituting the surroundings. A series of recognition items such as the detection of breakage levels of sidewalk blocks were defined by classifying according to the degree of impeding the movement of the transportation handicapped in traffic from the collected data. A road surface object recognition deep learning model was implemented. In the final stage of the study, the performance verification process of a deep learning model that automatically detects defective road surface objects through model learning and validation after processing, refining, and annotation of image data separated and collected in units of objects through actual driving. proceeded.

Quality Characteristics of Calcium Fortified Yogurt Prepared with Milk Mineral (우유무기질을 첨가하여 제조한 칼슘 강화 요구르트의 품질 특성)

  • Park, Dong June;Oh, Sejong;Imm, Jee-Young
    • Journal of Dairy Science and Biotechnology
    • /
    • v.40 no.2
    • /
    • pp.57-65
    • /
    • 2022
  • This study was conducted to evaluate the potential use of milk mineral (MM) as the calcium source for the production of calcium-fortified yogurt. MM was composed of 83% minerals, 7.5% lactose, 3.3% protein, and < 1% fat. Calcium (Ca) content in MM was about 46%; calcium: phosphorous ratio was 1.28:1. The aqueous solubility of Ca increased with the decrease in pH; the solubility at pH 4 and 5 was 98% and 53%, respectively. Ca-fortified yogurt with up to 200 mg Ca/100 mL did not show significant differences in acid production and number of viable cells; however, the viscosity increased significantly (p<0.05) with the increase in Ca levels. Microstructure analysis of Ca-fortified yogurt using confocal scanning laser microscopy indicated that the protein network became denser with increasing fortification with MM. There was no significant difference in the sensory quality between the control and Ca-fortified yogurts. Therefore, MM could be used for the production of Ca-fortified yoghurt without compromising the quality characteristics of yogurt.

A Study on the Vibration Analysis of Spindle Housing with High Strength Aluminum of 2NC Head in Five-axis Cutting Machine Training (5축 절삭가공기 교육 중 2NC 헤드의 고강도 알루미늄을 적용한 스핀들 하우징의 극한 조건의 진동해석에 관한 연구)

  • Lee, Ji Woong
    • Journal of Practical Engineering Education
    • /
    • v.14 no.1
    • /
    • pp.119-125
    • /
    • 2022
  • Materials used for education are materials such as SM20C, Al6061, and acrylic. SM20C materials are carbon steel and are often used in certification tests and functional competitions, but are also widely used in industrial sites. The Al6061 material is said to be a material that has lower hardness and stronger flexibility than carbon steel, so it is a material that generates a lot of compositional selection of tools. If students are taught practical training using acrylic materials, vibration occurs due to excessive cutting in some parts and damage to the tool occurs. In this process, we examine to what extent the impact on the 2NC head, which is a five-axis equipment, can affect precision control. The weakest part of the five-axis equipment can be said to be the weakest part of the head that controls the AC axis. When the accuracy and cumulative tolerance of this part occur, the accuracy of all products decreases. Therefore, the core part of the 2NC head, the spindle housing, was carried out using an Al7075 T6 (Alcoa, USA) material. In the process of vibration and cutting applied to this material, the analysis was conducted to find out the value applied to the finite element analysis under extreme conditions. It is hoped that this analysis data will help students see and understand the structure of 5-axis machining rather than 5-axis cutting.

Rules of Origin of Korea's FTAs: based on Restrictiveness Index (우리나라 FTA 원산지결정기준의 엄격성 분석: 국가 및 산업별 특성을 중심으로)

  • Kwon, Mi-Ok;Ra, Hee-Ryang
    • Korea Trade Review
    • /
    • v.41 no.3
    • /
    • pp.63-107
    • /
    • 2016
  • This paper analyzed the restrictiveness of the rules of origin of the 15 FTAs of Korea utilizing the restrictiveness index suggested by Estevadeordal(2000). The main purpose of the paper is to provide an update of the current status and characteristics of the restrictiveness of the rules of origin based on product type and country. The research showed that FTA with EU and Turkey showed the highest restrictiveness, whereas New Zealand, Peru and India showed the lowest. Overall, Korea's restrictiveness index was found to be at appropriate levels. Additionally, in terms of the current status by restrictiveness index, over time with the exception of European countries in the FTA, products with the lowest score in restrictiveness index of 2 continued to be processed in the Korea-Peru FTA which illustrated the current trend of easing restrictiveness. In terms of restrictiveness index based on product type, commodity products, processed food, clothing-fabric-general merchandise were found to be very strict. However, in categories such as general machinery, electronics, chemical products and precision instruments, the restrictiveness index showed the lowest readings. The results imply the high restrictiveness in sensitive products that are vulnerable from competition through high tariffs, and easing of restrictiveness in competitive products in order to vitalize trade. The results also show that in Korea's FTA, Korea's rules of origin in FTA vary and are sorted in a complicated manner. With an increasing number of FTAs and a number of different rules of origin, there is a need for standardized criteria for Korea. This study was significant in that it compiled all the rules of origin and the restrictiveness index of all FTAs that came into effect and have been negotiated in Korea. The results of the research are expected to be used as an informative and meaningful guideline for Korea's FTAs.

  • PDF

A Study on the Effectiveness of Emotional Communication According to Types of Emoticon - Focusing on the Differences in Gender and Major of the Receiver - (이모티콘 유형에 따른 감정소통의 효과성 연구 - 수신자의 성별 및 전공계열별 차이를 중심으로 -)

  • Kang, Jung Ae;Kim, Hyun Ji;Lee, Sang Soo
    • Design Convergence Study
    • /
    • v.15 no.4
    • /
    • pp.45-58
    • /
    • 2016
  • The purpose of this study is to investigate the most effective emoticon type in on-line communication context through analysis decoding(by their interpretation, empathy, reaction) of receiver about emotional message included the various emoticon types. Message types were all 5 - only text message and messages included texticon, graphicon, anicon, and photocon that reflected the transitional process of emoticon. Survey questionnaire that included various emotional situations was developed and utilized to undergraduate students to analyze the differences in their gender and majors. Results are as follow. First, the graphicon, anicon and photocon messages had higher effectiveness than others in the pleasure while the text only message had the highest effectiveness of them in the displeasure. Second, female students responded that the graphicon, anicon and photocon messages were more effective while male students responded that text only message was. Third, between Arts/Physical and Science/Engineering majors had significant differences in some message types, and especially Science/Engineering majors showed higher average than other majors in all of the emoticon types. These results can provide the information to design messages by the emotional situation of sender and gender and major of receiver.

Detecting Vehicles That Are Illegally Driving on Road Shoulders Using Faster R-CNN (Faster R-CNN을 이용한 갓길 차로 위반 차량 검출)

  • Go, MyungJin;Park, Minju;Yeo, Jiho
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.21 no.1
    • /
    • pp.105-122
    • /
    • 2022
  • According to the statistics about the fatal crashes that have occurred on the expressways for the last 5 years, those who died on the shoulders of the road has been as 3 times high as the others who died on the expressways. It suggests that the crashes on the shoulders of the road should be fatal, and that it would be important to prevent the traffic crashes by cracking down on the vehicles intruding the shoulders of the road. Therefore, this study proposed a method to detect a vehicle that violates the shoulder lane by using the Faster R-CNN. The vehicle was detected based on the Faster R-CNN, and an additional reading module was configured to determine whether there was a shoulder violation. For experiments and evaluations, GTAV, a simulation game that can reproduce situations similar to the real world, was used. 1,800 images of training data and 800 evaluation data were processed and generated, and the performance according to the change of the threshold value was measured in ZFNet and VGG16. As a result, the detection rate of ZFNet was 99.2% based on Threshold 0.8 and VGG16 93.9% based on Threshold 0.7, and the average detection speed for each model was 0.0468 seconds for ZFNet and 0.16 seconds for VGG16, so the detection rate of ZFNet was about 7% higher. The speed was also confirmed to be about 3.4 times faster. These results show that even in a relatively uncomplicated network, it is possible to detect a vehicle that violates the shoulder lane at a high speed without pre-processing the input image. It suggests that this algorithm can be used to detect violations of designated lanes if sufficient training datasets based on actual video data are obtained.

Characteristics of Functional Components of Red Ginseng Concentrate First Extracted at Low Temperature I - Focused on Ginsenoside - (저온에서 1차 추출한 홍삼농축액의 기능성분 특성 I - Ginsenoside 위주로 -)

  • Su Hyun Lee;Keon Shin;Seon Yeung Jo;Young Sig Park
    • Journal of Food Hygiene and Safety
    • /
    • v.38 no.3
    • /
    • pp.176-183
    • /
    • 2023
  • The extraction and filtration of red ginseng with a mixed solvent of water and alcohol-a common processing method-and the production of a concentrate through heat treatment, such as steaming, leads to its hydrolysis or polymerization. Approximately 200 ginsenosides have consequently been detected in small amounts, in addition to the identification of the functions of approximately 30 major ginsenosides. This complicates the identification of the functionality of red ginseng and its efficacy, and has negative effects as a functional food, as the astringent taste becomes stronger with an increase in the number of extractions. The red ginseng concentrate was, therefore, extracted at a low temperature (less than 40 ℃) and processed to eliminate these negative aspects, with a specific focus on the characteristics of the functional components of ginsenosides.