• 한국해양공학회지
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• 제11권3호
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• pp.39-47
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• 1997

Recently developed TMCP steels, which were manufactured by controlled rolling followed by accelerated cooling process, were examined to study their characteristics and weldability. Accelerated cooling type TMCP steel's hardness test result exhibited high value on weld zone. On the contrary, base metal and HAZ exhibited comparatively the similar value. On this experiment result Softening of HAZ is not occurred. in the-heat affected zone, grain size repression be caused by chemical composition properties which a small quantity Al-Ti-B-N. Changing stress ratio near-threshold fatigue crack propagation experiments were carried out. According to this result, crack propagation velocity of the HAZ exhibited slower than the base metal and near-threshold value had increased at the HAZ. Finally accelerated cooling type TMCP steels were exhibited excellent mechanical properties in both strength and toughness.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권4호
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• pp.1521-1537
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• 2021

Through information hiding technique, secret message can be hidden in pictures. Stego-image quality and hiding capacity are two important metrics for information hiding. To enhance these metrics, many schemes were proposed by scholars in recent years. Some of them are effective and successful, but there is still a room for further improvement. A high capacity information hiding scheme (PAMO, Pixel-value Adjustment with Modulus Operation Algorithm) is introduced in this paper. PAMO scheme uses pixel value adjustment with modulus operation to hide confidential data in cover-image. PAMO scheme and some referenced schemes are implemented in Python and experiments are carried out to evaluate their performance. In the experiments, PAMO scheme shows better performance than other methods do. When secret message length is less than 72000 bits, the highest hiding capacity of PAMO can reach 7 bits per pixel, at the same time the PSNR of stego-images is greater than 30 dB.

• Journal of Advanced Marine Engineering and Technology
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• 제31권5호
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• pp.575-582
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• 2007

In this paper, a 100 Watt high power amplifier has been implemented and performed evaluation, which is operating at UHF band ($470\;{\sim}\;806\;MHz$) for Digital TV repeater. To achieve increase of bandwidth and high power capability, 3-way power combiner and divider of Wilkinson type was adopted. In order to measure the fabricated 100 Watt power amplifier, the estimation technique function which makes equivalent mask was used. As a result of the measurement, the existence of pilot signal is confirmed and the signal transmitted at the rated output power 100 Watt is brought out the flat feature through 6 MHz bandwidth. and it resulted that its value was less than -47 dB at the edge of radiation channel and less than -110 dB at more than 6 MHz position from channel edge.

• 한국실내디자인학회논문집
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• 제7호
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• pp.31-37
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• 1996

The purpose of this study is to grasp the characteristics by image type in interior color. This experiment is carried out by the evaluation method of color simulation with the color image processor. And the result of this experimental evaluation is analyzed quantitatively by HAYASI 1 Program. The results of this analysis are as follows : 1) In casual and clear images, the most main colors are GY, PB, Y , and N, Casual image has high chroma and the most arrangement of colors is hue-contrast or contrast -harmony with white. Also the main colors of clear image are in identical or similar harmony with the hues of floor. 2) In romantic, elegant, pretty, and gorgeous images, the most main colors are GY, RP, R , YR and Y and the most arrangement of colors is identical or similar harmony. The romantic image of pastel tone is wholly lighter than the pretty image of bright tone. And elegant image is lower in chroma than romantic images, so generally dark. Also gorgeous image is the vivid tone with high chroma. 3) In chic and modern images, the main colors are the hues of B, PB, high value and low chroma with bright tone. Also, the main colors are in identical or similar harmony with the hues of floor : BG , B, PB and P. 4) In natural and semiclassic images, the main color is the warm color of Y, YR and the most arrangement of colors is identical or similar harmony. Also Semiclassic images is the dull tone with middle value and middle chroma and darker tone than natural image. 5) In dynamic image, the main color is the hue of N, Y, PB and GY and most of color is high chroma. And the most arrangement of colors is value-contrast.

• 한국산업융합학회 논문집
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• 제27권1호
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• pp.97-106
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• 2024

시료의 조단백질은 CJ4가 가장 높고 조지방, 수분, 회분, pH와 물리적인 특성은 주박분말이 많을수록 높았고 보수력은 낮았다. TBA의 CJ1은 지방산패 진행이 빨라 15일부터 가식할 수 없는 결과였다. 미생물 성장은 CJ1이 빠르게 증식하였고 CJ2, CJ3, CJ4는 15일 이후에도 부패취가 없어 주박분말이 저장성에 유용한 것으로 판단된다. 주박분말이 많을수록 L은 낮은 명도 a는 높은 적색 b는 높은 황색을 보였다. 관능검사 CJ1은 Color, Overall CJ2는 Flavor, Taste가 높은 선호도를 보였다. 주박을 첨가한 소시지의 외부 기호도는 CJ1를 내부 표현인 Overall은 CJ2를 활용한 저장성 연장관련 제품개발이 가능할 것으로 사료된다.

• 한국재료학회지
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• 제12권5호
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• pp.407-413
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• 2002

Eutectic high chromium cast irons containing 17%Cr and 26%Cr were produced for this research by making each of them solidify unidirectionally. Abrasion wear test against SiC or $Al_2$O$_3$bonded paper was carried out using test pieces cut cross-sectionally at several distances from the chill face of castings. The wear resistance was evaluated in connection with the parameters such as eutectic colony size($E_w$), area fraction of boundary region of the colony($S_B$) where comparatively large massive chromium carbides are crystallized and, average diameter of chromium carbides in the boundary region($D_c$). The wear rate($R_w$), which is a gradient of straight line of wear loss versus testing time, was influenced by the type and the particle size of the abrasives. The $R_w$ value against SiC was found to be larger than that against A1$_2$O$_3$under the similar abrasive particle size. In the case of SiC, the $R_w$ value increased with an increase in the particle size. The $R_w$ value also increased as the eutectic colony size decreased, and that of the 17%Cr iron was larger than that of the 26%Cr iron at the same $E_w$ value. Both of the $S_B$ and $D_c$ values were closely related to the $R_w$ value regardless of chromium content of the specimens. The $R_w$ values of the annealed specimens were greater than those of the as-cast specimens because of softened matrix structures. As for the relationship between wear rate and macro-hardness of the specimens, the hardness resulting in the minimum wear rate was found to be at 550 HV30.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 추계 학술논문 발표대회
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• pp.71-74
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• 2005

The viscosity of high-flowability paste is very high compared to normal concrete for the low water-binder ratio(W/B). Therefore, high-flowability concrete is positively necessary to high-range water reducing agent. High-Flowability paste can make much higher fluidity with no occurrence of segregation, by its higher viscosity and lower yield value than normal concrete. The flowability of high-flowability paste must be evaluated not only by convention consistency test such as slump test but also by the base of the rheological properties of the fresh concrete. The purpose of this study is to analyze the fluidity of high-flowability paste according to the addition ratio of the Melamine Sulphonate high-range water reducing agent.; high-flowability paste is considered as Bingham plastic fluid with the rheology parameters of the plaste viscosity and yield value.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제15권2호
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• pp.63-73
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• 2012

Development of antiviral resistance to lamivudine is the most important factor for the treatment failure. It is necessary to establish proper guidelines to overcome drug resistance for children with chronic hepatitis B. Primary treatment with lamivudine should be considered if patients are in immune-clearance phase and have persistently elevated ALT levels more than twice the upper limit of normal value. Before initiating the therapy, careful consideration of the patient's status is required to exclude abnormal liver function tests due to other causes. The treatment option should be carefully decided to suppress the viral replication effectively. To obtain good compliance, clinicians should educate patients and their parents. Appropriate monitoring for virologic breakthrough and genotypic resistance is important in deciding to change the treatment plan. Sequential monotherapy should be avoided and a combination of drugs in other categories is recommended. New antiviral agents, such as entecavir and tenofovir, which have high potency and high genetic barrier, are soon expected to be available for use with children.

• Journal of Electrical Engineering and Technology
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• 제11권2호
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• pp.499-507
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• 2016

Medical imaging techniques such as Magnetic Resonance Imaging (MRI), Computed Tomography (CT) and Ultrasound (US) produce a large amount of digital medical images. Hence, compression of digital images becomes essential and is very much desired in medical applications to solve both storage and transmission problems. But at the same time, an efficient image compression scheme that reduces the size of medical images without sacrificing diagnostic information is required. This paper proposes a novel threshold-based medical image compression algorithm to reduce the size of the medical image without degradation in the diagnostic information. This algorithm discusses a novel type of thresholding to maximize Compression Ratio (CR) without sacrificing diagnostic information. The compression algorithm is designed to get image with high optimum compression efficiency and also with high fidelity, especially for Peak Signal to Noise Ratio (PSNR) greater than or equal to 36 dB. This value of PSNR is chosen because it has been suggested by previous researchers that medical images, if have PSNR from 30 dB to 50 dB, will retain diagnostic information. The compression algorithm utilizes one-level wavelet decomposition with threshold-based coefficient selection.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2000년도 KIASC Conference 2000 / 2000년도 학술대회 논문집
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• pp.60-62
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• 2000

It is widely acknowledged that the value of critical current in High Temperature Superconducting (HTS) tape has a great influence on B. Therefore, when HTS cable is designed, a method to reduce the B should be considered in order to improve the capacity. This paper deals with the influence of the space between each HTS tape by using 2D analytical method. From the analysis results, it is found that the decrease of the space causes the decrease of B. Moreover, another HTS cable, which has a very small space, is analyzed by 3D analytical method and it is manufactured. The validity of these analysis results are verified by comparison with experimental results.