• Title/Summary/Keyword: inspection machines

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Modern Paper Quality Control

  • Olavi Komppa
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2000.06a
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    • pp.16-23
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    • 2000
  • The increasing functional needs of top-quality printing papers and packaging paperboards, and especially the rapid developments in electronic printing processes and various computer printers during past few years, set new targets and requirements for modern paper quality. Most of these paper grades of today have relatively high filler content, are moderately or heavily calendered , and have many coating layers for the best appearance and performance. In practice, this means that many of the traditional quality assurance methods, mostly designed to measure papers made of pure. native pulp only, can not reliably (or at all) be used to analyze or rank the quality of modern papers. Hence, introduction of new measurement techniques is necessary to assure and further develop the paper quality today and in the future. Paper formation , i.e. small scale (millimeter scale) variation of basis weight, is the most important quality parameter of paper-making due to its influence on practically all the other quality properties of paper. The ideal paper would be completely uniform so that the basis weight of each small point (area) measured would be the same. In practice, of course, this is not possible because there always exists relatively large local variations in paper. However, these small scale basis weight variations are the major reason for many other quality problems, including calender blacking uneven coating result, uneven printing result, etc. The traditionally used visual inspection or optical measurement of the paper does not give us a reliable understanding of the material variations in the paper because in modern paper making process the optical behavior of paper is strongly affected by using e.g. fillers, dye or coating colors. Futhermore, the opacity (optical density) of the paper is changed at different process stages like wet pressing and calendering. The greatest advantage of using beta transmission method to measure paper formation is that it can be very reliably calibrated to measure true basis weight variation of all kinds of paper and board, independently on sample basis weight or paper grade. This gives us the possibility to measure, compare and judge papers made of different raw materials, different color, or even to measure heavily calendered, coated or printed papers. Scientific research of paper physics has shown that the orientation of the top layer (paper surface) fibers of the sheet paly the key role in paper curling and cockling , causing the typical practical problems (paper jam) with modern fax and copy machines, electronic printing , etc. On the other hand, the fiber orientation at the surface and middle layer of the sheet controls the bending stiffness of paperboard . Therefore, a reliable measurement of paper surface fiber orientation gives us a magnificent tool to investigate and predict paper curling and coclking tendency, and provides the necessary information to finetune, the manufacturing process for optimum quality. many papers, especially heavily calendered and coated grades, do resist liquid and gas penetration very much, bing beyond the measurement range of the traditional instruments or resulting invonveniently long measuring time per sample . The increased surface hardness and use of filler minerals and mechanical pulp make a reliable, nonleaking sample contact to the measurement head a challenge of its own. Paper surface coating causes, as expected, a layer which has completely different permeability characteristics compared to the other layer of the sheet. The latest developments in sensor technologies have made it possible to reliably measure gas flow in well controlled conditions, allowing us to investigate the gas penetration of open structures, such as cigarette paper, tissue or sack paper, and in the low permeability range analyze even fully greaseproof papers, silicon papers, heavily coated papers and boards or even detect defects in barrier coatings ! Even nitrogen or helium may be used as the gas, giving us completely new possibilities to rank the products or to find correlation to critical process or converting parameters. All the modern paper machines include many on-line measuring instruments which are used to give the necessary information for automatic process control systems. hence, the reliability of this information obtained from different sensors is vital for good optimizing and process stability. If any of these on-line sensors do not operate perfectly ass planned (having even small measurement error or malfunction ), the process control will set the machine to operate away from the optimum , resulting loss of profit or eventual problems in quality or runnability. To assure optimum operation of the paper machines, a novel quality assurance policy for the on-line measurements has been developed, including control procedures utilizing traceable, accredited standards for the best reliability and performance.

An Investigation on Milking Disturbances of Mammary System (젖소 필유계(泌乳係)의 착유장애(搾乳障碍)에 관한 조사(調査))

  • Cheong, Chang Kook;Nam, Tchi Chou;Shin, Tong Woo
    • Korean Journal of Veterinary Research
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    • v.21 no.2
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    • pp.151-159
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    • 1981
  • An investigation on various causes of milking disturbances resulting from injuries and abnormalities of mammary system were made in 2,179 Holstein cows. To perform this investigation, 69 dairy farms of the suburban area of Seoul city, Gyeonggi-do and Chungnam provinces were andomly selected and subjected. Diagnosis was made by means of inspection and palpation of teat, insertion of teat canula, checking milk machines, anamneses and farm records. This investigation was, actively done from March 1977 to February 1979, The results obtained were summerized as follows; 1. It was found that 446 cows, accounting for 20.48% of 2,179 cows inspected, had supernumerary teats. Among them 53.59% had one, 43.72% had two, 2.47% had three, and 0.22% had four supernumerary teats, respectively. 2. Dry off quarters were found in 158 quarters which turned out to be 1.8% of 8,716 quarters inspected. Among dry off quarters, 62.02% seemed to be caused by mastitis, 30.37% by acquired teat obstructions, and 7.59% by congenital blind teats and glands respectively. 3. Teat sphincter stenosis was found in 154 teats of 50 cows, which represents 1.76% of 8,716 teats and 2.29% of 2,179 cows inspected, respectively. Among 154 teats with teat sphincter stenosis, 138 teats (85.7%) of 33 cows were found to be congenital and revealed highest incidence. 4. Loose sphincter was found in 78 teats of 36 cows, which figure 0.89% of 8,7l6 teats and 1.69% of 2,179 cows inspected, respectively. Among 78 teats with loose sphincter, 52 teats (66.66%) of 13 cows were found to be congenital and revealed highest incidence. 5. Injured teat tip caused by over milking of milk machine, was found in 229 teats of 156 cows, which figure 2.63% of 8,716 teats and 7.15% of 2,179 cows observed, respectively. 6. Other miscellaneous injuries and congenital abnormalities of teats and udders were diagnosed as follows: The teat laceration was found in 34 teats (0.39% of 8,716 teats), fissure of teat skin in 24 teats (0.28% of 8,716 teats), stricture of teat cistern in 21 teats (0.24% of 8,716 teats), teat fistula in 12 teats (0.14% of 8,716 teats), papillomas on testes in 8 teats (0.09% of 8,716 teats). Knothole orifice in 7 teats (0.08% of 8,716 teats), subcutaneous abscess of udder in 5 quarters (0.05% of 8,716 teats), membraneous obstruction of teat cistern in 4 teats (0.05% of 8,716 teats), and congenital short teat in 8 teats (0.09% of 8,716 teats), respectively.

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3D Film Image Inspection Based on the Width of Optimized Height of Histogram (히스토그램의 최적 높이의 폭에 기반한 3차원 필름 영상 검사)

  • Jae-Eun Lee;Jong-Nam Kim
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.2
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    • pp.107-114
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    • 2022
  • In order to classify 3D film images as right or wrong, it is necessary to detect the pattern in a 3D film image. However, if the contrast of the pixels in the 3D film image is low, it is not easy to classify as the right and wrong 3D film images because the pattern in the image might not be clear. In this paper, we propose a method of classifying 3D film images as right or wrong by comparing the width at a specific frequency of each histogram after obtaining the histogram. Since, it is classified using the width of the histogram, the analysis process is not complicated. From the experiment, the histograms of right and wrong 3D film images were distinctly different, and the proposed algorithm reflects these features, and showed that all 3D film images were accurately classified at a specific frequency of the histogram. The performance of the proposed algorithm was verified to be the best through the comparison test with the other methods such as image subtraction, otsu thresholding, canny edge detection, morphological geodesic active contour, and support vector machines, and it was shown that excellent classification accuracy could be obtained without detecting the patterns in 3D film images.

Accurate Quality Control Method of Bone Mineral Density Measurement -Focus on Dual Energy X-ray Absorptiometry- (골밀도 측정의 정확한 정도관리방법 -이중 에너지 방사선 흡수법을 중심으로-)

  • Kim, Ho-Sung;Dong, Kyung-Rae;Ryu, Young-Hwan
    • Journal of radiological science and technology
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    • v.32 no.4
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    • pp.361-370
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    • 2009
  • The image quality management of bone mineral density is the responsibility and duty of radiologists who carry out examinations. However, inaccurate conclusions due to lack of understanding and ignorance regarding the methodology of image quality management can be a fatal error to the patient. Therefore, objective of this paper is to understand proper image quality management and enumerate methods for examiners and patients, thereby ensuring the reliability of bone mineral density exams. The accuracy and precision of bone mineral density measurements must be at the highest level so that actual biological changes can be detected with even slight changes in bone mineral density. Accuracy and precision should be continuously preserved for image quality of machines. Those factors will contribute to ensure the reliability in bone mineral density exams. Proper equipment management or control methods are set with correcting equipment each morning and after image quality management, a phantom, recommended from the manufacturer, is used for ten to twenty-five measurements in search of a mean value with a permissible range of ${\pm}1.5%$ set as standard. There needs to be daily measurement inspections on the phantom or at least inspections three times a week in order to confirm the existence or nonexistence of changes in values in actual bone mineral density. in addition, bone mineral density measurements were evaluated and recorded following the rules of Shewhart control chart. This type of management has to be conducted for the installation and movement of equipment. For the management methods of inspectors, evaluation of the measurement precision was conducted by testing the reproducibility of the exact same figures without any real biological changes occurring during reinspection. Bone mineral density inspection was applied as the measurement method for patients either taking two measurements thirty times or three measurements fifteen times. An important point when taking measurements was after a measurement whether it was the second or third examination, it was required to descend from the table and then reascend. With a 95% confidence level, the precision error produced from the measurement bone mineral figures came to 2.77 times the minimum of the biological bone mineral density change. The value produced can be stated as the least significant change (LSC) and in the case the value is greater, it can be stated as a section of genuine biological change. From the initial inspection to equipment moving and shifter, management must be carried out and continued in order to achieve the effects. The enforcement of proper quality control of radiologists performing bone mineral density inspections which brings about the durability extensions of equipment and accurate results of calculations will help the assurance of reliable inspections.

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Studies on the Processing and Management Forms of Filatures (우리나라 제사공장의 공정 관리실태에 관한 조사연구)

  • 송기언;이인전
    • Journal of Sericultural and Entomological Science
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    • no.12
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    • pp.37-45
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    • 1970
  • The processing management forms of our country's filature factories in 1969 are summarized as follows. (1) About 80% of total cocoon collection is made within 5 days involving peak day, and 10% of cocoon collection is finished until 3 days before and after the peak day, (2) About 92% of alive cocoons transported on unpaved road, and about 40% of the cocoons purchased by all factories are loaded on trucks from common selling station which is far beyond 40km, therefore a new packing system of alive cocoons to drop the damage of cocoon qualities, should be taken. (3) 22% of all factories in our. country have only low-temperature cocoon drying machine. Therefore the installment of hot-air cocoon drying machine is required urgently. (4) In view of cocoon qualities in our country, the grouping method of cocoon for reeling. taken by about 50% of the factories at percent, which classify cocoons for reeling as high group (1,2,3,4 grades) and low group(5,6 grades), will have to be replaced by the method tat classify them high group (1,2 grades) middle group (3,4 grades), low group (5,6 grades). (5) The .ratio of cocoon assorting stood about 10% in multi-ends reeling, about 15% in automatic reeling, conclusively, the ratio of cocoon assorting for automatic reeling was higher tan that for multi-ends reeling. One person's ability for a day in cocoon assorting reaches to about 80-100kg. (6) Cocoon cooking condition requires the increase of the cooking time, the pressure and temperature used to be prolonged as much as the qualities of cocoons are material cocoon ior automatic and double cocoon machines are treated uncompletely. (7) Automatic silk reeling is being performed at 1-2$^{\circ}C$ lower in reeling water temperature and operated at about twice velocity. (8) The temperature and humidity of rereeling room stood at 25$^{\circ}C$, 67.2% R.H and 32.3$^{\circ}C$, 51.9% R.H of rereeling machine are showed, Average rereeling velocity is 233m/min and large reefs charged for one person are 7.5 reels and form of skein used in all factories is double skein. (9) About 73% of water sources for filature used under-earth water. About 48% of all filature factories in our country have not yet water purifying equipments. Installation of the equipment for these factories seems to be urgent, (10) Denier .balance, sizing reel, seriplane, are being used in most factories as self-inspection apparatus. (11) More than 90% of the factories use the vacum tank in rereeling process and about 20% of them use it in cocoon cooing process (12) Only 21% of the factories use chemicals in filature process. About all them use "Seracol 100" in cocoon cooking process and "Seracol 500" in rereeling process, (13) Above survey results explain each all factories show large difference in the processing management. Therefore, it is believed that intercommunication through seminar or technical exchange will contribute to the production evaluation of cocoon in our filature industry.

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