• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.4
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• pp.552-560
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• 1997

Analysis is performed to determine the optimal lengths or cross-sectional areas of refrigerator-cooled current leads that can be applied to the conduction-cooled superconducting systems. The binary current lead is composed of the series combination of a normal metal at the upper(warm) part and a high $T_c$ superconductor(HTS) at the lower(cold) part. The heat conduction toward the cold end of HTS part constitutes a major refrigeration load. In addition, the joint between the parts should be cooled by a refrigerator in order to reduce the load at the low end and maintain the HTS part in a superconducting state. The sum of the work inputs required for the two refrigeration loads needs to be minimized for an optimal operation. In this design, three simple models that depict the refrigeration performance as functions of cooling temperature are developed based on some of the existing refrigerators. By solving one-dimensional conduction equation that take into account the temperature-dependent properties of the materials, the refrigeration works are numerically calculated for various values of the joint temperature and the sizes of two parts. The results show that for given size of HTS, there exist the optimal values for the joint temperature and the size of the normal metal. It is also found that the refrigeration work decreases as the length of HTS increases and that the optimal size of normal metal is quite independent of the size of HTS. For a given length of HTS, there is an optimal cross-sectional area and it increases as the length increases. The dependence of the optimal sizes on the refrigerator models employed are presented for 1kA leads.

• Korean Journal of Community Nutrition
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• v.7 no.4
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• pp.578-584
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• 2002

This study was designed to investigate the association between the period of engraftment and the nutritional status of patient s undergoing bone marrow transplantation for acute myelogenous leukemia (AML). Nutritional status was evaluated by body mass index (BMI), percentage of ideal body weight (PIBW), percentage of weight loss, and serum albumin, total protein (T protein), hemoglobin (HGB) and hematocrit (HCT) levels on the day prior to transplantation and on the day of bone marrow transplantation. The periods of engraftment were determined by absolute neutrophil counts (ANC) above $500/mm^3$ from the day of bone marrow transplantation. The study subjects were 80 patients (55 males, 25 females) with acute myelogenous leukemia admitted to the University Hospital in Seoul. The result of this study is as follows : Tie nutritional status values of the majority of patients on the day prior to transplantation were in the normal range except for HGB and HCT ; however, during hospitalization, all of the levels of the nutritional status values were significantly decreased. The periods of engraftment of the abnormal group according to their BMI, PIBW, HGB and HCT levels on the day of bone marrow transplantation showed no difference when compared to the normal group. However, the periods of engraftment of the abnormal group, according to the percentage of weight loss, albumin, and T protein levels were significantly decreased when compared to the normal group. Therefore, the nutritional status of patients at the time of transplant had a noticeable influence on the periods of engraftment. Our results suggested that nutritional status is a critical factor of engraftment in BMT during pre-transplant and post-transplant. Futhermore, we recommend that the process of nutritional preparation for the transplant should initiate immediately after the transplant decision has been made.

• Journal of the Korean Society of Physical Medicine
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• v.10 no.2
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• pp.29-34
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• 2015

PURPOSE: The purpose of present study was to introduces an exceptional case in measurement methods (CVA, CRA and Cobb angle) to identify the FHP with verified reliability and validity. Subjects: Three males aged 30 years were recruited: A Normal, B and C who have FHP. METHODS: All the subjects were measured CVA, CRA and Cobb angle with the Photogrammetry and Radiography. RESULTS: The results revealed that it is not enough for measurement methods to identify the FHP using CVA, CRA and Cobb angle. On Photogrammetry values; CVA had $65^{\circ}$, CRA was $148^{\circ}$ of Normal subject A and CVA had $61^{\circ}$, CRA was $149^{\circ}$ of FHP subject B and CVA had $51^{\circ}$, CRA was $149^{\circ}$ of FHP subject C. On Radiography values; CVA had $73^{\circ}$, CRA was $148^{\circ}$ and Cobb was $50^{\circ}$ of Normal subject A and CVA had $70^{\circ}$, CRA was $150^{\circ}$ and Cobb was $53^{\circ}$ of FHP subject B and CVA had $61^{\circ}$, CRA was $153^{\circ}$ and Cobb was $31^{\circ}$ of FHP subject C. CONCLUSION: The reliable CVA, CRA and Cobb angle use methods from the previous studies might not be suitable for the diagnose the FHP. We think that it is necessary to have more detailed evaluation methods and the radiography is also needed for clear evaluations because of some possible exceptions.

• Korean Journal of Community Nutrition
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• v.9 no.3
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• pp.292-302
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• 2004

The nutritional status of middle-aged overweight and control normal subjects were evaluated for the purpose of providing the background information of the degenerative disease control. A survey was conducted with 293 healthy subjects (121 males and 172 females) between the ages 40-64. The average BMI (body mass index) of male subjects was 24.5 $\pm2.75$, and that of females was 23.5 $\pm2.87$. The average values of WHR (waist-hip ratio) were 0.88 $\pm0.04$, for males and 0.82 $\pm0.07$, for females. The normal BMI group (BMI 18.5-22.9) comprised 28.9% of males and 47.1% of females. The percentage of overweight subjects (BMI 23-24.9) was 26.4% of males and 30.8% of females. The obese group (BMI ＞ 25) was 44.6% of males ana 22.1% of females, showing the greater rate of obese state among male subjects. The average energy intakes were 76.6 $\pm14.9$% for males and 77.8 $\pm12.6$, % for females, protein intakes were 108.0 $\pm24.6$% for males and 111.2 $\pm22.7$, % for females of the RDA levels. The average intakes of other nutrients were above the 75% of RDA levels except calcium. The average nutrient intakes of the three subgroups according to their BMI values were not different for both males and females. There were weak correlations between obesity and blood biochemical indices. There were positive correlations between BMI or WHR and hemoglobin, hematocrit, fasting glucose, total cholesterol, triglyceride, AST or ALT. There were negative correlations between BMI or WHR and HDL-cholesterol. These results suggest that the obesity rate of middle-aged is an influential factor of chronic disease. The middle-aged subjects of this study with higher educational and socioeconomic background tend to have desirable nutrition knowledge and attitude, but the application of their knowledge or attitude was relatively poor.

• Solar Energy
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• v.20 no.1
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• pp.45-54
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• 2000

Five direct/diffuse decomposition models were validated using the eight years data set of direct normal beam insolation measured in Seoul. The comparison has been performed In terms of the widely used statistical indicators such as MBE, RMSE, CV(RMSE), t-Statistic and Degree of Agreement. Result indicates that most of the correlations exhibit a tendency to underestimate the direct normal beam insolation except Bouguer's model. Most of big discrepancies between the measured and the predicted values was mainly shown in near the sunrising and the sunset period. Even though the investigated five models showed fairly large disagreement for the measured values by 34%$\sim$48% of CV(RMSE), Udagawa's correlation which includes the effect of solar altitude variation appears to performs always better in every statistical error tests.

• Journal of Yeungnam Medical Science
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• v.39 no.3
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• pp.230-234
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• 2022

Background: To date, there have been no studies on the normal anatomic values of the anal sphincter in healthy Koreans. Therefore, this study aimed to determine the normal anatomic values of transanal ultrasonography (TAUS). Methods: The thickness of the external anal sphincter (EAS) and internal anal sphincter (IAS) was measured by TAUS from healthy Korean volunteers between September 2019 and August 2021. Results: Thirty-six volunteers with a median age of 37 years (range, 20-77 years) and a median body mass index (BMI) of 23.5 kg/m² (range, 17.2-31.2 kg/m²) were examined. The median thickness of the EAS at 4 cm and 2 cm from the anal verge was 7.4 mm (range, 5.8-8.8 mm) and 6.5 mm (range, 5.6-8.0 mm), respectively. The median thickness of the IAS at 2 cm from the anal verge was 1.8 mm (range, 0.8-4.3 mm). There were no differences in sphincter muscle thickness between the sexes. However, the EAS tended to thicken as the BMI increased (EAS at 2 cm and 4 cm from the anal verge, Spearman rho=0.433, 0.363; p=0.008 and p=0.029, respectively). Conclusion: In healthy Korean, the median thickness of the IAS at 2 cm from the anal verge was 1.8 mm and the median thickness of the EAS at 2 cm and 4 cm from the anal verge was 6.5 mm and 7.4 mm respectively. There were no differences in anal sphincter thickness between sexes, but BMI was related to EAS thickness.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.5
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• pp.773-782
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• 2022

Estimation of cable tension through proper measurements is one of the essential tasks in evaluating the safety of cable structures. In this paper, a study on cable tension estimation using the built-in accelerometer and camera in a smartphone was conducted. For the experimental study, visual displacement measurement using a smartphone camera and acceleration measurement using a built-in accelerometer were performed in the cable-stayed bridge model. The estimated natural frequencies and transformed tensions from these measurements were compared with the theoretical values and results from the normal visual displacement method. Through comparison, it can be seen that the error between the method using the smartphone and the normal visual displacement is sufficiently small to be acceptable. It has also been shown that those errors are much smaller than the difference between the values calculated by the theoretical model. These results show that the deviation according to the type of measurement method is not large and it is rather important to use an appropriate mathematical model. In conclusion, in the case of cable tension estimation, it can be said that the visual displacement measurement and acceleration using a smartphone can be a sufficiently applicable method, just like the normal visual displacement method. It is also noteworthy that the smartphone accelerometer has a larger magnitude error and has more limitations such as high-frequency sampling instability compared to the visual displacement method, but shows almost the same performance as the visual displacement method in this cable tension estimation.

• Applied Microscopy
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• v.51
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• pp.6.1-6.9
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• 2021

Histopathology is a well-established standard diagnosis employed for the majority of malignancies, including breast cancer. Nevertheless, despite training and standardization, it is considered operator-dependent and errors are still a concern. Fractal dimension analysis is a computational image processing technique that allows assessing the degree of complexity in patterns. We aimed here at providing a robust and easily attainable method for introducing computer-assisted techniques to histopathology laboratories. Slides from two databases were used: A) Breast Cancer Histopathological; and B) Grand Challenge on Breast Cancer Histology. Set A contained 2480 images from 24 patients with benign alterations, and 5429 images from 58 patients with breast cancer. Set B comprised 100 images of each type: normal tissue, benign alterations, in situ carcinoma, and invasive carcinoma. All images were analyzed with the FracLac algorithm in the ImageJ computational environment to yield the box count fractal dimension (Db) results. Images on set A on 40x magnification were statistically different (p = 0.0003), whereas images on 400x did not present differences in their means. On set B, the mean Db values presented promising statistical differences when comparing. Normal and/or benign images to in situ and/or invasive carcinoma (all p < 0.0001). Interestingly, there was no difference when comparing normal tissue to benign alterations. These data corroborate with previous work in which fractal analysis allowed differentiating malignancies. Computer-aided diagnosis algorithms may beneficiate from using Db data; specific Db cut-off values may yield ~ 99% specificity in diagnosing breast cancer. Furthermore, the fact that it allows assessing tissue complexity, this tool may be used to understand the progression of the histological alterations in cancer.

• Tuberculosis and Respiratory Diseases
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• v.86 no.3
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• pp.226-233
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• 2023

Background: Inactive or old, healed tuberculosis (TB) on chest radiograph (CR) is often found in high TB incidence countries, and to avoid unnecessary evaluation and medication, differentiation from active TB is important. This study develops a deep learning (DL) model to estimate activity in a single chest radiographic analysis. Methods: A total of 3,824 active TB CRs from 511 individuals and 2,277 inactive TB CRs from 558 individuals were retrospectively collected. A pretrained convolutional neural network was fine-tuned to classify active and inactive TB. The model was pretrained with 8,964 pneumonia and 8,525 normal cases from the National Institute of Health (NIH) dataset. During the pretraining phase, the DL model learns the following tasks: pneumonia vs. normal, pneumonia vs. active TB, and active TB vs. normal. The performance of the DL model was validated using three external datasets. Receiver operating characteristic analyses were performed to evaluate the diagnostic performance to determine active TB by DL model and radiologists. Sensitivities and specificities for determining active TB were evaluated for both the DL model and radiologists. Results: The performance of the DL model showed area under the curve (AUC) values of 0.980 in internal validation, and 0.815 and 0.887 in external validation. The AUC values for the DL model, thoracic radiologist, and general radiologist, evaluated using one of the external validation datasets, were 0.815, 0.871, and 0.811, respectively. Conclusion: This DL-based algorithm showed potential as an effective diagnostic tool to identify TB activity, and could be useful for the follow-up of patients with inactive TB in high TB burden countries.

• Korean Journal of Veterinary Research
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• v.64 no.2
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• pp.14.1-14.6
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• 2024

In human, ultrasonography is used to measure the pennation angle in various muscles to identify muscle functions such as force production, and to study alterations of the pennation angle during muscle contraction, hypertrophy, and atrophy. However, assessments of the pennation angle have not yet been conducted in dogs. This study aims to assess the normal pennation angle of the tibialis cranialis muscle in dogs using ultrasound and to detect changes in this angle in dogs with muscular atrophy. Sixty-eight healthy dogs were examined to establish normal values, while 12 ataxic and 12 lame dogs with suspected hindlimb muscle atrophy were also included. The pennation angle was measured using ultrasound at the midpoint between the proximal end of the tibia and the malleolus, measuring the angle between the muscle bundle and the deep aponeurosis. To confirm the significance between the 5 breeds and to identify a difference between normal and atrophied muscles, statistical analysis was conducted. The study found no significant difference in pennation angle between breeds, with mean values (± standard deviation) of 4.97° (± 1.88) in neutral, 7.25° (± 2.68) in flexion, and 3.31° (± 1.33) in extension positions. Decrease of the pennation angle was identified in muscle atrophy and the flexion position was determined to be the most appropriate for pennation angle measurement of tibialis cranialis muscle. We recommend considering the pennation angle as a valuable indicator of muscle health in dogs, as it demonstrates significant potential for diagnosing and monitoring muscular conditions.