• Journal of Welding and Joining
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• v.27 no.6
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• pp.36-42
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• 2009

In the present day, new performances are demanded for automobile body steel sheet for example, light weight, durability, resistance corrosion and environmental protection. For an improvement of resistance corrosion, European automobile companies developed pre-sealed steel in 1990's. Pre-sealed steel have organic coated layer upper zinc coated layer. Evaluating a resistance spot weldability of pre-sealed steel plate is important because resistance spot welding is used mainly in automobile body joining process. In this study, evaluating a weldability of pre-sealed steel plate was carried out using lobe diagram, dynamic resistance and high-speed image. Usually, Pre-sealed steel has poor weldability than GA steel's. To improve a weldability of pre-sealed steel sheet, pre-current was applied to welding process. Pre-current is applied prior to base-current. In conclusion, the weldability of pre-sealed steel has been improved than GA steel's by applying pre-current.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.926-930
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• 2006

Current image retrieval techniques have shortcomings that make it difficult to search for images based on a semantic understanding of what the image is about. Since an image is normally associated with multiple contexts (e.g. when and where a picture was taken,) the knowledge of these contexts can enhance the quantity of semantic understanding of an image. In this paper, we present a context-aware image retrieval system, which uses the context information to infer a kind of metadata for the captured images as well as images in different collections and databases. Experimental results show that using these kinds of information can not only significantly increase the retrieval accuracy in conventional content-based image retrieval systems but decrease the problems arise by manual annotation in text-based image retrieval systems as well.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.3 s.96
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• pp.329-333
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• 2005

This paper is concerned with the measurement of low-frequency vibrations of structures using the image processing method. To measure the vibrations visually, the measurement system consists of a camera, an image grabber board, and a computer. The specific target installed on the structure is used to calculate the vibration of structure. The captured image is then converted into a pixel-based data and then analyzed numerically. The limitation of the system depends on the image capturing speed and the size of image. In this paper, we propose the methodology for the vibration measurement using the image processing method. The method enables us to measure the displacement directly without any contact. The current resolution of the vibration measurement is limited to sub centimeter scale. However, the frequency bandwidth and resolution can be enhanced by a high-speed and high-resolution image processing system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.887-890
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• 2012

Image recognition is one of the most important research directions of pattern recognition. Image based road automatic identification technology is widely used in current society, the intelligence has become the trend of the times. This paper studied the image segmentation algorithm theory and its application in road signs recognition system. With the help of image processing technique, respectively, on road signs automatic recognition algorithm of three main parts, namely, image segmentation, character segmentation, image and character recognition, made a systematic study and algorithm. The experimental results show that: the image segmentation algorithm to establish road signs recognition model, can make effective use of smart phone system and application.

• IEMEK Journal of Embedded Systems and Applications
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• v.4 no.3
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• pp.103-111
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• 2009

Software update has been regarded as one of fundamental functions in wireless sensor networks. It can disseminate a delta-image between a current software image operating on a sensor node and its new image in order to reduce an update image(transmission data) size, resultantly saving energy. In addition, code-banking capability of micro-controllers can decrease the update image size. In order to maximize the efficiency of the software update, the proposed scheme exploits both the delta-image and the code-banking at the same time. Besides, it additionally delivers a recovery delta-image to properly handle abnormal conditions, such as message corruptions and unexpected power-off during the update.

• Current Optics and Photonics
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• v.4 no.4
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• pp.302-309
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• 2020

An image encryption scheme based on the quick response (QR) code as a data container has aroused wide interest due to the lossless recovery of the decrypted image. In this paper, we apply this method to multi-image encryption. However, since the decrypted image is affected by crosstalk noise, the number of multi-image encryptions is severely limited. To solve this problem, we analyzed the performance of QR code as a data container, and processed the decrypted QR code using the proposed method, so that the number of multi-image encryptions is effectively increased. Finally, we implemented a large image (256 × 256) encryption and decryption.

• Current Optics and Photonics
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• v.8 no.4
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• pp.391-398
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• 2024

An image reconstruction algorithm is vital for the image quality of a photonic integrated interferometric imaging (PIII) system. However, image reconstruction algorithms have limitations that always lead to degraded image reconstruction. In this paper, a novel image reconstruction algorithm based on deep learning is proposed. Firstly, the principle of optical signal transmission through the PIII system is investigated. A dataset suitable for image reconstruction of the PIII system is constructed. Key aspects such as model and loss functions are compared and constructed to solve the problem of image blurring and noise influence. By comparing it with other algorithms, the proposed algorithm is verified to have good reconstruction results not only qualitatively but also quantitatively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.10
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• pp.2237-2246
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• 2012

A bias circuit required for an oral sensor is manufactured inside the oral sensor chip to reduce its size and cost. The proposed DC-DC converter supplies the required reference and bias currents for their corresponding regulators by using IREF of the reference current generator. Their target voltages of the voltage regulators are regulated by the negative mechanism by generating their reference voltages required for their corresponding regulators. In addition, a constant current IB0/IB1 is supplied by being mirrored by a current mirror ratio and then VREF is generated. It is confirmed by measurements that the average volatge, ${\sigma}$, and $4{\sigma}$ of the designed DC-DC converter for intra oral sensors with a $0.18{\mu}m$ X-ray CMOS process are within their required ranges. And the line-pair pattern image shows a high-resolution characteristic without blurring. Also, a good oral image can be obtained.

• Journal of the Korean Society of Radiology
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• v.3 no.3
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• pp.27-35
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• 2009

In this study, the basic research verifying possibility of applications as radiology image sensor in Digital Radiography was performed, the radiology image sensor was fabricated using double layer technique tio decrease dark current. High efficiency material in substitution for a-Se have been studied as a direct method of imaging detector in Digital Radiography to decrease dark current by using Hetero junction already used as solar cell, semiconductor. Particle-In-Binder method is used to fabricate radiology image sensor because it has a lot of advantages such as fabrication convenient, high yield, suitability for large area sensor. But high leakage current is one of main problem in PIB method. To make up for the weak points, double layer technique is used, and it is considered that high efficient digital radiation sensor can be fabricated with easy and convenient process. In this study, electrical properties such as leakage current, sensitivity is measured to evaluate double layer radiation sensor material.

• The Korean Journal of Food And Nutrition
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• v.18 no.2
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• pp.115-126
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• 2005

This Quantitative study was investigated to examine the relationship between self-esteem on body image and disordered eating patterns in some university students. This study used a cross-sectional study design. Total 347 students participated in this study (88 male and 259 female) among three universities. The assessment of eating disorder was conducted by Eating Attitudes Test (EAT-26), a score of >or=20 identified individuals likely have an eating disorder, including anorexia nervosa and bulimia nervosa. Ideal body weight and current body weight were completed with self-evaluation. A distorted body image was independently related to the eating problem in the Logistic regression analysis. There were stronger relationships between their EAT-26 scores and their expected weight changes and weight control behaviors. Compared with the men, women showed highly wishful to loss for current body weight. In the relationship between score of EAT-26 and BMI distance by sex, levels of eating disorder showed linearly elevated toward increased BMI distance (Ideal BMI-Current BMI) (F-value=18.794, p<0.0001) in women, but there were not significant in men (F-value=2.028, p>0.05). In estimate on state-trait anxiety inventory according to quartile of BMI distance by sex, levels of state-trait anxiety were not significant difference by degree of body dissatisfaction in all sex. In addition, higher distorted body image was significantly increased numbers of weight control method and experience of side effects in female, but there were not showed significant relation between two variables in male.