• Journal of radiological science and technology
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• v.45 no.2
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• pp.127-134
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• 2022

In order to overcome the image quality limitations of the conventional C-arm, a flat panel detector (FPD) is used to enhance spatial resolution, detective quantum efficiency, frame rate, and dynamic range. Three-dimensional (3D) visualized information can be obtained from C-arm computed tomography (CT) equipped with an FPD, which can reduce patient discomfort and provide various medical information to health care providers by conducting procedures in the interventional procedure room without moving the patient to the CT scan room. Unlike a conventional C-arm device, a C-arm CT requires different basic safety and essential performance evaluation criteria; therefore, in this study, basic safety and essential performance evaluation criteria to protect patients, medical staff, and radiologists were derived based on International Electrotechnical Commission (IEC) standards, the Ministry of Food and Drug Safety (MFDS) standards in Korea, and the rules on the installation and operation of special medical equipment in Korea. As a result of the study, six basic safety evaluation criteria related to electrical and mechanical radiation safety (leakage current, collision protection, emergency stopping device, overheating, recovery management, and ingress of water or particulate matter into medical electrical (ME) equipment and ME systems: footswitches) and 14 essential performance evaluation criteria (accuracy of tube voltage, accuracy of tube current, accuracy of loading time, accuracy of current time product, reproducibility of radiation output, linearity and consistency in radiography, half layer value in X-ray equipment, focal size and collimator, relationship between X-ray field and image reception area, consistency of light irradiation versus X-ray irradiation, performance of the mechanical device, focal spot to skin distance accuracy, image quality evaluation, and technical characteristic of cone-beam computed tomography) were selected for a total of 20 criteria.

• Journal of Korean Society of Rural Planning
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• v.17 no.2
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• pp.33-41
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• 2011

To evaluate the value of a preserved tree as rural landscape resource, the growth environment and health condition was investigated, and the image evaluation was implemented on land~ape architectural major undergraduate students for zelkova trees in Yesan-gun. The image evaluation results of zelkova trees were as followings; 1) Typical image of preserved tree examined by Semantic Differential Scale were 'Old', 'Big', and 'Good'. 2) The 'big' image of zelkova tree and the height of tree, the width of tree crown, the breast girth of tree, the root girth of tree, the external formation of tree, and the health of tree bark is mutually related. Especially, the correlation between the 'big' and the external formation and the width of tree crown is high. 3) Typical image of preserved tree examined by Likert Scale were 'Natural', 'Green', 'Peaceful', and 'Rural'. 4) The preservation necessity for preserved tree was highly related with the state of ground, and the management necessity for preserved tree was highly related with contamination level and the state of ground. The appropriate management plan for preserved tree are proposed to improve the quality of rural landscape(basis of these results).

• Journal of radiological science and technology
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• v.26 no.3
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• pp.7-11
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• 2003

Currently, many hospitals are hastening to introduce digital radiography systems. This is a direct result of the intentions to improve medical services and to digitalize radiology information systems, and is also leading to the improvement of medical imaging technology. Throughout F/S system's long history, many people have researched the image quality and dosage concerning these systems, and as a result, huge improvements in the dosage of patients were possible. Similarly, I believe that DR systems need the same kind of effort. Of course, decreases in dosage that ignore image quality are unthinkable. The results of experiments conducted by five hospitals during a period of 3 months brought to us the conclusions listed below. 1. Based on the comparison and analysis of the exposure control of F/S systems and DR systems, DR systems generally showed higher exposure control for parts of the phantom that became thicker, and the exposure control improved rapidly as the thickness increased. 2. DR systems still proved to be somewhat deficient in resolution measurements compared to existing F/S systems. The image processing part of DR systems contributed much to these result. 3. Under conditions used clinically, the dosage measurements of DR systems were generally higher regardless of region. 4. According to the evaluation of image quality, DR systems showed a higher degree of satisfaction as the thickness of the region became thinner. As mentioned above and based on the mutual relationship experiments between the dosage and image quality of F/S systems and DR systems, research to increase the satisfaction of DR systems must be considered.

• Journal of radiological science and technology
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• v.46 no.4
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• pp.295-301
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• 2023

In addition to protocol adjustments during CT examinations, the height of the CT table can also affect image quality. Therefore, this study aimed to investigate the change in image quality depending on the height of the table in brain CT, which accounts for a large proportion of CT examinations, by measuring signal to contrast to noise ratio (CNR) and noise power spectrum (NPS) using the head phantom and evaluating them. The head phantom images were acquired using Philips Brilliance iCT 256. When the image was acquired, the table height was adjusted to 815, 865, 915, 965, 1015, and 1030 mm, respectively, and each scan was performed 3 times for each height. The CNR result showed the highest value at 965 mm, which is the height adjacent to the center of the head phantom. NPS showed the lowest NPS at 915 mm, the center of the head phantom in the low frequency region. From these results, it can be seen that the height of the table in CT examination is closely related to the image quality, and it can be seen the characteristics of image quality according to CT table through quantitative evaluation methods such as CNR and NPS.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.30-34
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• 2009

Purpose: Many companies developed a lot of programs with continuous effort for program upgrading. With this acquire superior image quality for the purpose of quick examination and progress in spatial resolution. This study was to obtained clinical usefulness on a appropriate parameter of FWHM for speed and alpha value for superior image quality. Materials and Methods: Gamma camera by Siemens (e.cam) and spatial resolution phantom and four quadrant bar phantom used. Compared for FWHM by changed scan speed 15, 20, 25, 30, 35, 40 cm/min in scatter and non scatter in Onco Flash of spatial resolution phantom. Visual evaluation of count rate and bar phantom image for increased of alpha value of 10% in 0~100%. Results: FWHM by the scan speed was 9.37, 9.40, 9.28, 9.30, 9.31, 9.53 mm in the scatter. Count rate increased alpha value 10% increased. Visual evaluation was suitable to below 30%, Therefore spatial resolution improved on FWHM at the scan speed 25~35 cm/min applying for alpha value 30% in Onco Flash was average 9.3 mm less than FWHM of below 15 cm/min and above 40 cm/min. Conclusion: We found on appropriate parameter to progress of image quality. And there be a useful guideline for you that appropriate scan speed on vary in parameters of reduction on examination time and advancing image quality.

• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.157-165
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• 2023

Ultrasound imaging uses sound waves of frequencies to cause physical actions such as reflection, absorption, refraction, and transmission at the edge between different tissues. Improvement is needed because there is a lot of noise due to the characteristics of the data generated from the ultrasound equipment, and it is difficult to grasp the shape of the tissue to be actually observed because the edge is vague. The edge enhancement method is used as a method to solve the case where the edge surface looks clumped due to a decrease in image quality. In this paper, as a method to strengthen the interface, the quality improvement was confirmed by strengthening the interface, which is the high-frequency part, in each image using an unsharpening mask and high boost. The mask filtering used for each image was evaluated by measuring PSNR and SNR. Abdominal, head, heart, liver, kidney, breast, and fetal images were obtained from Philips epiq5g and affiniti70g and Alpinion E-cube 15 ultrasound equipment. The program used to implement the algorithm was implemented with MATLAB R2022a of MathWorks. The unsharpening and high-boost mask array size was set to 3*3, and the laplacian filter, a spatial filter used to create outline-enhanced images, was applied equally to both masks. ImageJ program was used for quantitative evaluation of image quality. As a result of applying the mask filter to various ultrasound images, the subjective image quality showed that the overall contour lines of the image were clearly visible when unsharpening and high-boost mask were applied to the original image. When comparing the quantitative image quality, the image quality of the image to which the unsharpening mask and the high boost mask were applied was evaluated higher than that of the original image. In the portal vein, head, gallbladder, and kidney images, the SNR, PSNR, RMSE and MAE of the image to which the high-boost mask was applied were measured to be high. Conversely, for images of the heart, breast, and fetus, SNR, PSNR, RMSE and MAE values were measured as images with the unsharpening mask applied. It is thought that using the optimal mask according to the image will help to improve the image quality, and the contour information was provided to improve the image quality.

• The Journal of Fisheries Business Administration
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• v.40 no.2
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• pp.1-25
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• 2009

The major part of non-commercial food service is food service for school which has no any objective quality standards. Each school has different standard when they buy seafood for SFS(School Food Service). The research purpose is whether or not the extrinsic cues of the seafood such as price, the source origin, company image, safety standards, etc or the intrinsic cues such as fishy smell, the hardiness of fish meat, others have any effect on the seafood evaluation when school nutritionist purchase it, for more objective basis. The research method is distributing questionnaire survey through e-mail or directly visiting the schools from October 30 to November 9, 2007. The questionnaire was distributed to 70 nutritionists of food service for elementary school in Busan. Total 50 questionnaires are used as data in the statistical analysis using SPSS package software. The research results are; First, there is interaction effect between the extrinsic and intrinsic cues of seafood for SFS. That is when the school nutritionist valued on intrinsic cues of seafood such as a fishy smell, the hardiness of fish meat and etc influence on the extrinsic cues such as price, source origin, reliable circulation process, HACCP application, etc. Second, the extrinsic cues of the seafood give no effect on perceived quality. Since seafood for SFS are heavy buying, prearrangement contract and most of them using pre-treated frozen aquatics. Third, the intrinsic cues of the seafood give no effect on perceived quality. The extrinsic cues consist of 5 parts namely "opening about quality", "source origin", "company image", "safety/standards" and "price/package". However, "safety/standard" was the only affecting factor to perceive quality. The reason is that in fact they have no standards or any document proving the quality of the seafood unless safety standards factor. Last, the perceived quality is an important factor for perceived value and purchase intention. It is showed that there is a path to form a willing to buy through the perceived value after school nutritionist recognizes the perceived quality.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.284-291
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• 2013

The importance of ultrasound examination in the field of medical imaging has been emphasized and the interest in sonographic image evaluation is growing. However image evaluations by the non-standardized criteria and methods, so establishment of legal provisions and objective evaluation criteria are needed. In this study, we used SNR to find out more quantitative way and supplement the limitations of the existing phantom image evaluation. The results of acquired 8 images using ATS-539 multipurpose phantom were compared in SNR of sensitivity and gray-scale dynamic range. In the result of the experiment, excellent equipment of existing phantom images are G1, S1 and G2 in regular sequence. In SNR of sensitivity, G1, S1 and G2 and in SNR of gray-scale dynamic range, S1 G1 and G2 in order. In the conclusion, all the experiment results did not show big difference and regular pattern neither. Therefore, the new evaluation measures should be used with the existing phantom image evaluation method for more objective and quantitative evaluation of the ultrasound imaging device.

• The Journal of the Korea Contents Association
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• v.18 no.9
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• pp.34-43
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• 2018

The purpose of this study is to develop measurement program model for a human being-oriented product through the between the evaluation factors of portrait and general preferences of portraits. We added new items that are essential to the image evaluation by analysing previous studies. In this study, We identified the facial focus for the first step, and the portraits were evaluated by dividing it into objective and subjective image quality evaluation items. RSC Contrast and Dynamic Range were selected as the Objective evaluation items, and the numerical values of each image could be evaluation items, and the numerical values of each image could be evaluated by statistical analysis method. Facial Exposure, Composition, Position, Ratio, Out of focus, and Emotions and Color tone of image were selected as the Subjective evaluation items. In addition, a new face recognition algorithm is applied to judge the emotions, the manufacturer can get the information that they can analyze the people's emotion. The program developed to quantitatively and qualitatively compiles the evaluation items when evaluating portraits. The program that I developed through this study can be used an analysis program that produce the data for developing the evaluation model of the product more suitable to general users of imaging systems.

• Journal of Biosystems Engineering
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• v.32 no.3
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• pp.166-172
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• 2007

Egg quality indices are related with freshness, size of air chamber, loss of weight, and viscosity of the yolk and the protein. However, since the described quality parameters require measured in a destructive way, it is not suitable to inspect the egg quality with complete enumeration. Therefore, this study was performed to investigate the potential of image analysis method for evaluation of internal egg quality. Samples of 90 fresh eggs were collected immediately after laying and stored up to 24 days. Five eggs were randomly drawn from each storage condition (packing vs unpacking) at a regular interval and loss of weight, specific gravity and size of air chamber were measured. The image analysis for nondestructive measurement of size of air chamber was also studied. Results showed that the egg weight and gravity gradually decreased with increasing of storage days, while the size of air chamber linear increased caused by evaporation of water through the shell. A relationship a between conventional method and the image analysis method for measuring the size of air chamber was developed with the correlation coefficient of 0.928. The new finding implied that image analysis might provide a useful nondestructive tool to assess internal egg quality.