• Food Engineering Progress
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• v.23 no.2
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• pp.87-93
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• 2019

Temperature distribution studies were performed in steam-air retort to investigate the influence of various processing conditions (come-up time, sterilization temperature, and internal pressure throughout the steam-air retort). Retort temperature data were analyzed for temperature deviations during holding phase, maximum temperature difference between test locations at the beginning and after 1, 3, and 5 min of the holding phase, and box-and-whiskers plots for each location during the holding phase. The results showed that high sterilization temperature led to a more uniform temperature distribution than low sterilization temperature (pasteurization). In pasteurization condition, the temperature stability was slightly increased by increasing pressure during the holding phase. On the other hand, the temperature stability was slightly decreased in high sterilization temperature condition. Programming of the come-up phase did not affect the temperature uniformity. In addition, the slowest cold spot was found at the bottom floor during the holding phase in all conditions. This study determined that the temperature distribution is affected by retort processing conditions, but the steam-air retort needs more validation tests for temperature stability.

• Progress in Medical Physics
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• v.32 no.4
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• pp.179-184
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• 2021

This study aimed to determine the optimal thickness of the active layer and scan mode for a flexible radiochromic film (F-RCF) based on the active lithium salt of pentacosa-10,12-diynoic acid (LiPCDA). F-RCFs of 90, 120, 140, and 170-㎛ thickness were fabricated using LiPCDA. Several pieces of the F-RCFs were exposed to doses ranging from 0 to 3 Gy. Transmission and reflection modes were used to scan the irradiated F-RCFs. Their dose-response curves were obtained using a second-order polynomial equation. Their sensitivity was evaluated for both scanning modes, and the uniformity of the batch was also examined. For both the transmission and reflection modes, the sensitivity increased as the film thickness increased. For the reflection mode, the dose response increased dramatically under 1 Gy. The value of the net optical density varied rapidly as the thickness of the film increased. However, the dose-response curves showed a supralinear-curve relationship at doses greater than 2 Gy. The sensitivity of the reflection scan at doses greater than 2 Gy was higher than that of the reflection scan within 0-2 Gy. The sensitivity steadily decreased with increasing doses, and the sensitivity of the two modes was within 0.1 to 0.2 at 2 Gy and was saturated beyond that. For the transmission scan, the sensitivity was approximately 0.2 at 3 Gy. For the intra-batch test result, the maximum net optical density difference of the intra-batch was 5.5% at 2 Gy and 7.4% at 0.2 Gy in the transmission and reflection scans, respectively. In the low-dose range, film thickness of more than 120-㎛ was proper in the transmission mode. In contrast, the transmission mode showed a better result compared to the reflection mode. Therefore, the proper scan mode should be selected according to the dose range.

• Geomechanics and Engineering
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• v.33 no.1
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• pp.29-40
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• 2023

Xanthan gum and starch compound biopolymer (XS), an environmentally friendly soil-binding material produced from natural resources, has been suggested as a slope protection material to enhance soil strength and erosion resistance. Insufficient wet strength and the consequent durability concerns remain, despite XS biopolymer-soil treatment showing high strength and erosion resistance in the dried state, even with a small dosage of soil mass. These concerns need to be solved to improve the field applicability and post-stability of this treatment. This study explored the utilization of an alkaline-based cation crosslinking method using calcium hydroxide and sodium hydroxide to induce non-thermal gelation, resulting in the enhancement of the wet strength and durability of biopolymer-treated soil. Laboratory experiments were conducted to assess the unconfined compressive strength and cyclic wetting-drying durability performance of the treated soil using a selected recipe based on a preliminary gel formation test. The results demonstrated that the uniformity of the gel structure and gelling time varied depending on the ratio of crosslinkers to biopolymer; consequently, the strength of the soil was affected. Subsequently, site soil treated with the recipe, which showed the best performance in indoor assessment, was implemented on the field slope at the bridge abutment via compaction and pressurized spraying methods to assess feasibility in field implementation. Moreover, the variation in surface soil hardness was monitored periodically for one year. Both slopes implemented by the two construction methods showed sufficient stability against detachment and scouring, with a higher soil hardness index than the natural slope for a year.

• The Journal of Advanced Prosthodontics
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• v.15 no.5
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• pp.248-258
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• 2023

PURPOSE. This study aims to evaluate the effects of exposure energy on the lateral resolution and mechanical strength of dental zirconia manufactured using digital light processing (DLP). MATERIALS AND METHODS. A zirconia suspension and a custom top-down DLP printer were used for in-office manufacturing. The viscosity of the suspension and uniformity of the exposed light intensity were controlled. Based on the exposure energy dose delivered to each layer, the specimens were classified into three groups: low-energy (LE), medium-energy (ME), and high-energy (HE). For each energy group, a simplified molar cube was used to measure the widths of the outline (X_o and Y_o) and isthmus (X_i and Y_i), and a bar-shaped specimen of the sintered body was tested. A Kruskal-Wallis test for the lateral resolution and one-way analysis of variance for the mechanical strength were performed (α = .05). RESULTS. The zirconia green bodies of the ME group showed better lateral resolution than those of the LE and HE groups (both P < .001). Regarding the flexural strength of the sintered bodies, the ME group had the highest mean value, whereas the LE group had the lowest mean value (both P < .05). The ME group exhibited fewer agglomerates than the LE group, with no distinctive interlayer pores or surface defects. CONCLUSION. Based on these findings, the lateral resolution of the green body and flexural strength of the sintered body of dental zirconia could be affected by the exposure energy dose during DLP. The exposure energy should be optimized when fabricating DLP-based dental zirconia.

• International Journal of Computer Science & Network Security
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• v.24 no.1
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• pp.163-177
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• 2024

The fingerprint image quality relies on the clearness of separated ridges by valleys and the uniformity of the separation. The condition of skin still dominate the overall quality of the fingerprint. However, the identification performance of such system is very sensitive to the quality of the captured fingerprint image. Fingerprint image quality analysis and enhancement are useful in improving the performance of fingerprint identification systems. A fuzzy technique is introduced in this paper for both fingerprint image quality analysis and enhancement. First, the quality analysis is performed by extracting four features from a fingerprint image which are the local clarity score (LCS), global clarity score (GCS), ridge_valley thickness ratio (RVTR), and the Global Contrast Factor (GCF). A fuzzy logic technique that uses Mamdani fuzzy rule model is designed. The fuzzy inference system is able to analyse and determinate the fingerprint image type (oily, dry or neutral) based on the extracted feature values and the fuzzy inference rules. The percentages of the test fuzzy inference system for each type is as follow: For dry fingerprint the percentage is 81.33, for oily the percentage is 54.75, and for neutral the percentage is 68.48. Secondly, a fuzzy morphology is applied to enhance the dry and oily fingerprint images. The fuzzy morphology method improves the quality of a fingerprint image, thus improving the performance of the fingerprint identification system significantly. All experimental work which was done for both quality analysis and image enhancement was done using the DB_ITS_2009 database which is a private database collected by the department of electrical engineering, institute of technology Sepuluh Nopember Surabaya, Indonesia. The performance evaluation was done using the Feature Similarity index (FSIM). Where the FSIM is an image quality assessment (IQA) metric, which uses computational models to measure the image quality consistently with subjective evaluations. The new proposed system outperformed the classical system by 900% for the dry fingerprint images and 14% for the oily fingerprint images.

• The korean journal of orthodontics
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• v.33 no.2 s.97
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• pp.121-130
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• 2003

The purpose of this study was to evaluate the possibile clinical application of electroplating to increase diameter of an orthodontic wire, through examining the change of physical properties. The diameter of stainless steel orthodontic wire was increased from 0.016 inch to 0.018 inch by electroplating in a bath of nickel sulfate 100g/L, nickel chloride 60g/L, boric acid 30g/L, and sodium chloride 50g/L, under the conditions of 1.7V, $25\~29^{\circ}C\;and\;3.1\~3.3pH$. During the electroplating, the rate of diameter increase was measured every minute. To investigate uniformity, the diameter was measured at three different locations of each wire specimen aster electroplating. An X-ray diffraction test was performed to analyze the nature of the electroplated metal. Following heat treatment to improve adhesion between the wire and electroplated metal, a three-point bending test was conducted to compare stiffness, field strength, and ultimate strength among four wire groups; 0.016 inch, electroplated 016, electroplated and heat-treated 016, and 0.018 inch wires. Through the comparison of each wire group, following results were obtained. 1. In the load-deflection graph, the curve of the electroplated group was Placed between that of the 0.016 inch group and the 0.018 inch group, and the owe was closer to the 0.018 inch group by heat treatment. 2. In the electroplated and heat-treated 016 wire group, the values of stiffness, yield strength and ultimate strength showed higher tendency than in the original 0.016 Inch group. Stiffness and ultimate strength showed statistically significant differences between two groups. 3. Stiffness, yield strength, and ultimate strength of electroplated wire presented lower values than those of 0.018 inch wire group. 4. Stiffness, yield strength, and ultimate strength of electroplated and heat-treated wire showed higher tendency than those of electroplated wire group, and ultimate strength showed statistically significant difference between two groups. 5. After electroplating, the difference in diameter between the three locations was within $0.1\~0.3\%$ variation, and showed no statistical significance.

• Progress in Medical Physics
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• v.26 no.4
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• pp.193-200
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• 2015

The aim of this study is to present commissioning results of the ViewRay system. We verified safety functions of the ViewRay system. For imaging system, we acquired signal to noise ratio (SNR) and image uniformity. In addition, we checked spatial integrity of the image. Couch movement accuracy and coincidence of isocenters (radiation therapy system, imaging system and virtual isocneter) was verified. Accuracy of MLC positioing was checked. We performed reference dosimetry according to American Association of Physicists in Medicine (AAPM) Task Group 51 (TG-51) in water phantom for head 1 and 3. The deviations between measurements and calculation of percent depth dose (PDD) and output factor were evaluated. Finally, we performed gamma evaluations with a total of 8 IMRT plans as an end-to-end (E2E) test of the system. Every safety system of ViewRay operated properly. The values of SNR and Uniformity met the tolerance level. Every point within 10 cm and 17.5 cm radii about the isocenter showed deviations less than 1 mm and 2 mm, respectively. The average couch movement errors in transverse (x), longitudinal (y) and vertical (z) directions were 0.2 mm, 0.1 mm and 0.2 mm, respectively. The deviations between radiation isocenter and virtual isocenter in x, y and z directions were 0 mm, 0 mm and 0.3 mm, respectively. Those between virtual isocenter and imaging isocenter were 0.6 mm, 0.5 mm and 0.2 mm, respectively. The average MLC positioning errors were less than 0.6 mm. The deviations of output, PDDs between mesured vs. BJR supplement 25, PDDs between measured and calculated and output factors of each head were less than 0.5%, 1%, 1% and 2%, respectively. For E2E test, average gamma passing rate with 3%/3 mm criterion was $99.9%{\pm}0.1%$.

• Progress in Medical Physics
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• v.19 no.2
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• pp.102-112
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• 2008

We developed a high-resolution micro-CT system based on rotational gantry and flat-panel detector for live mouse imaging. This system is composed primarily of an x-ray source with micro-focal spot size, a CMOS (complementary metal oxide semiconductor) flat panel detector coupled with Csl (TI) (thallium-doped cesium iodide) scintillator, a linearly moving couch, a rotational gantry coupled with positioning encoder, and a parallel processing system for image data. This system was designed to be of the gantry-rotation type which has several advantages in obtaining CT images of live mice, namely, the relative ease of minimizing the motion artifact of the mice and the capability of administering respiratory anesthesia during scanning. We evaluated the spatial resolution, image contrast, and uniformity of the CT system using CT phantoms. As the results, the spatial resolution of the system was approximately the 11.3 cycles/mm at 10% of the MTF curve, and the radiation dose to the mice was 81.5 mGy. The minimal resolving contrast was found to be less than 46 CT numbers on low-contrast phantom imaging test. We found that the image non-uniformity was approximately 70 CT numbers at a voxel size of ${\sim}55{\times}55{\times}X100\;{\mu}^3$. We present the image test results of the skull and lung, and body of the live mice.

• Culinary science and hospitality research
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• v.21 no.3
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• pp.198-211
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• 2015

The following research was done to develop a low calorie muffin that has good taste, as well as nutritional benefit. This was done through adding various nutritional qualities of Makgeolli Lees to muffins. It was found that adding Makgeolli Lees substantially increased the amount of ash, crude protein, crude fiber, and moisture. However, it decreased the amount of crude fat. It was also found that the volume, height, and weight all increased with a lower baking loss rate. Other testing on the hardness, expand chewiness, gumminess, and cohesiveness of the muffins with different amounts of Makgeolli Lees found that more Makgeolli Lees led to a lower hardness and chewiness. However, it did not affect the gumminess. "MLM10" with 10 g of added Makgeolli Lees had a cohesiveness that was significantly different from other samples. The cohesiveness of the other samples was substantially lower. "L-value", or lightness, as well as yellowness, decreased as more Makgeolli Lees was added. On the other hand, "a-value", or redness, increased as more Makgeolli Lees was added. A sensory test proved that Makgeolli Lees added muffins were not preferred over the control group in its color, texture, and overall preference, but was evaluated as "good". However, the Makgeolli Lees added muffins were evaluated better than the control group in the categories of "expanded", "uniformity", and "he size of the pores". Therefore, creating muffins by using Makgeolli Lees instead of fat was proven to be possible, and furthermore proved to be a viable substitute.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6925-6931
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• 2015

LED(Light Emitting Diode) is used in various filed like a display because of low power consuming, long life span, high brightness, rapid response time and environmental-friendly characteristic. General fabrication method is combination blue light LED chip with yellow fluorescent substance. Because this way is suitable for industry field in terms of convenience, economic, efficiency. In white light LED packaging process, encapsulation process that is dispensing fluorescent substance with silicon to blue light LED chip is most important. So, in this paper we develop EHD pump system using voice coil motor and electrostatic pump for dispensing fluorescent substance. For these things we conduct basic test about liquid surface profiles by voltage and process time. Through this data we decide optimal process condition and verify the optimal condition using design of experiment method. And to confirm uniformity of the condition, we conduct repeat dispensing test.