Jaejoon Kim

Nonlinear, non-stationary image processing technique for eddy current NDE

Automatic analysis of eddy current (EC) data has facilitated the analysis of large volumes of data generated in the inspection of steam generator tubes in nuclear power plants. The traditional procedure for analysis of EC data includes data calibration, pre-processing, region of interest (ROI) detection, feature extraction and classification. Accurate ROI detection has been enhanced by pre-processing, which involves reducing noise and other undesirable components as well as enhancing defect indications in the raw measurement. This paper presents the Hilbert-Huang Transform (HHT) for feature extraction and support vector machine (SVM) for classification. The performance is shown to significantly better than the existing rule based classification approach used in industry.

Development of medical imaging viewer: role in DICOM standard

PACS is an integrated communication network system which is consists of image acquisition devices, storage archiving units, display stations, computer processors, and database management systems. In medical industry, each medical equipment and PACS has been introduced the DICOM standard for closely connected usage with rather than independent usage. In this paper, we have reviewed the performance of JPEG and JPCG2000 used as medical image compression and file format. In addition, we introduced the DICOM viewer for JPEG and JPEG200 including raw image format.

MPEG-21 in broadcasting: the novel digital broadcast item model

The MPEG experts are currently developing the MPEG-21 set of standards and this includes a framework and specifications for digital rights management (DRM), delivery of quality of services (QoS) over heterogeneous networks and terminals, packaging of multimedia content and other things essential for the infrastructural aspects of multimedia content distribution. Considerable research effort is being applied to these new developments and the capabilities of MPEG-21 technologies to address specific application areas are being investigated. One such application area is broadcasting, in particular the development of digital TV and its services. In more practical terms, digital TV addresses networking, events, channels, services, programs, signaling, encoding, bandwidth, conditional access, subscription, advertisements and interactivity. MPEG-21 provides an excellent framework of standards to be applied in digital TV applications. Within the scope of this research work we describe a new model based on MPEG-21 and its relevance to digital TV: the digital broadcast item model (DBIM). The goal of the DBIM is to elaborate the potential of MPEG-21 for digital TV applications. Within this paper we focus on a general description of the DBIM, quality of service (QoS) management and metadata filtering, digital rights management and also present use-cases and scenarios where the DBIM’s role is explored in detail.

Development of Personal Information Protection Model using a Mobile Agent

This paper proposes a personal information protection model that allows a user to regulate his or her own personal information and privacy protection policies to receive services provided by a service provider without having to reveal personal information in a way that the user is opposed to. When the user needs to receive a service that requires personal information, the user will only reveal personal information that they find acceptable and for uses that they agree with. Users receive desired services from the service provider only when there is agreement between the user`s and the service provider`s security policies. Moreover, the proposed model utilizes a mobile agent that is transmitted from the user`s personal space, providing the user with complete control over their privacy protection. In addition, the mobile agent is itself a self-destructing program that eliminates the possibility of personal information being leaked. The mobile agent described in this paper allows users to truly control access to their personal information.

Assessment of nuclear fuel pellets using X-ray tomography

Fuel rods in nuclear power plants consist of uranium dioxide pellets enclosed in Zirconium alloy (Zircaloy) tubes. It is vitally important for the pellet surface to remain free fr om pits, cracks and chipping defects after it is loaded into t he tubes to prevent local hot spots during reactor operation. The inspection of the fuel rod presents several challenges. In this pa per, we investigate the feasibility of using X-ray tomography inspection to detect flaws on the surface of pellets contained wit hin the tubes using very limited number of projections.

173 MELATONIN ALLEVIATES THE ENDOPLASMIC RETICULUM STRESS THROUGH THE REGULATING OF UNFOLDING PROTEIN RESPONSE SIGNALING DURING PORCINE OOCYTE MATURATION IN VITRO

Unfolding protein response (UPR) is a defence mechanism during endoplasmic reticulum (ER) stress in mammalian cells. Especially, UPR genes and regulation of reactive oxygen species is involved in ER stress response on porcine oocyte maturation in vitro. Some studies have shown that melatonin treatment results in reducing oxidative stress, a protective function of free radical damage in oocyte maturation and embryo development. Also, melatonin has an important role in reducing reactive oxygen species and ER stress. However, it is unknown how the changes of UPR genes expression levels are affected the porcine oocyte maturation. In addition, there are no reports about ER stress recovery mechanism by melatonin during porcine oocyte maturation. Here, we investigated the UPR signal genes (Bip/Grp78, Atf4, p90/p50Atf6, and Xbp1) and ER-stress mediated apoptosis factors (Chop and Cleaved caspase 3) in porcine oocyte maturation in vitro. Expression of Chop and Cleaved caspase 3 mRNA levels were significantly increased (P<0.01) in matured oocytes (metaphase II; 44h) in vitro. Porcine oocytes were cultured in maturation medium with ER stress inducer, tunicamycin (Tm), and supplemented with various concentrations (1, 5, and 10μgmL-1) of Tm for 0 to 44h. Our results indicated that the proportion of matured oocytes was significantly decreased in Tm-treated groups in a dose-dependent manner (60.1±1.3, 46.5±2.1, and 38.9±5.1% at 1, 5, and 10μgmL-1 of Tm) compared with the control group (76.6±1.9%). Likewise, mRNA expression of UPR regulator genes (Grp78/Bip, Aft4, Xbp1, Chop, and Cleaved caspase 3) was decreased by melatonin treatment (0.1μM, 22-44h) after pretreatment of Tm (5μgmL-1, 0-22h) during oocyte maturation. Our results demonstrated that the roles of melatonin as UPR signaling regulator for reducing ER stress are essential for promotion of porcine oocyte maturation and cumulus cell expansion of cumulus-oocyte complex. Moreover, the current study was initiated to confirm a functional link between effect of melatonin and regulating of UPR signaling in porcine oocytes maturation. These results suggest that melatonin improve the oocyte maturation and cumulus cells expansion by regulating of UPR signal genes against the ER stress during the porcine in vitro maturation process.

172 THE APOPTOTIC EFFECTS OF BISPHENOL A-INDUCED MITOCHONDRIAL-DERIVED REACTIVE OXYGEN SPECIES ON MATURATION OF PORCINE OOCYTES IN VITRO

Bisphenol A (BPA) is well known as oestrogen-like chemical and it is widely used in plastic products. Many studies have reported that BPA exposure has a well-known toxicity effect on reproduction function, such as reducing the number of ovulated oocytes, oocyte quality, and maturation rate. Recently, BPA induced mitochondrial-derived reactive oxygen species (mito-ROS) and disrupted mitochondrial homeostasis by increasing of superoxide anions production. In this study, we investigated how the regulation of mito-ROS production may play a critical role in meiotic maturation and expansion of cumulus cells during the in vitro maturation progression of porcine oocytes. Furthermore, we investigated the toxicity effect of BPA exposure on mitochondrial functions and mito-ROS production during porcine oocyte maturation in vitro. All results were analysed using a 1-way ANOVA followed by Bonferronis and Tukeys Multiple Comparison Test and t-tests. First, porcine oocytes were matured in NCSU-23 medium supplemented with BPA (50, 75, and 100µM) for 44h. Our results indicated that the rates of matured oocytes were significantly decreased by BPA exposure in a dose-dependent manner (69.4±5.1, 50.9±6.3, and 29.9±5.8% for BPA treatments of 50, 75, and 100μM) compared with control group (70.2±7.8%; P<0.05). Next, we confirmed the secretion functions of oocyte and cumulus cell of cumulus-oocyte complex (COC) and ROS production. Cumulus cell secretion factors (has2, tnfaip6, and cx37) mRNA expression in COC were decreased in the BPA-treated (75µM) group. In addition, mRNA expressions of mitochondrial-specific antioxidant enzymes (sod2, P<0.001; prdx3, P<0.01; prdx5, P<0.001) and mitochondrial apoptosis genes (bax and caspase-3, P<0.01) were significantly increased in COC of the BPA-treated (75µM) group. We measured mitochondrial membrane potential and mito-ROS production using JC-1 analysis and Mito-SOX staining, respectively. The BPA treatment caused a rapid decrease of mitochondrial membrane potential maintenance and increase of mito-ROS production in porcine COC. Moreover, mitochondrial-specific ROS scavenger, Mito-Tempo (0.1µM) treatment was significantly increased the meiotic maturation of porcine oocytes compared with control group (78.5±3.5v. 65.8±5.0%; P<0.05). Based on these results, we first confirmed that BPA exposure reduces the meiotic maturation and cumulus cells expansion of COC by increasing mito-ROS production during porcine oocyte maturation in vitro. Therefore, controlling of mito-ROS for mitochondrial function maintenance and apoptosis plays a critical role in improving porcine oocyte maturation in vitro.

Automated Multichannel Signal Classification Systems for Ultrasonic Nondestrucitve Evaluation

A key requirement in most ultrasonic weld inspection systems is the ability for rapid automated analysis to identify the type of flaw. Incorporation of spatial correlation information from adjacent A-scans can improve performance of the analysis system. This paper describes two neural network based classification techniques that use correlation of adjacent A-scans. The first method relies on differences in individual A-scans to classify signals using a trained neural network, with a post-processing mechanism to incorporate spatial correlation information. The second technique transforms a group of spatially localized signals using a 2-dimensional transform, and principal component analysis is applied to the transform coefficients to generate a reduced dimensional feature vectors for classification. Results of applying the proposed techniques to data obtained from weld inspection are presented, and the performances of the two approaches are compared.

ROI Detection Using Spatial Kernel Based Filter for Steam Generator Tube Inspection in Eddy Current Nondestructive Evaluation

A combined image processing algorithm for ROI detection is presented for automatic analysis of eddy current data collected during the inspection of steam generator tubes in nuclear power plants.

Personal Information Protection Model Based on Mobile Agent

This paper proposes a personal information protection model that allows a user to regulate his or her own personal information and privacy protection policies to receive services provided by a service provider without having to reveal personal information in a way that the user is opposed to. When the user needs to receive a service that requires personal information, the user will only reveal personal information that they find acceptable and for uses that they agree with. Users receive desired services from the service provider only when there is agreement between the user’s and the service provider’s security policies. Moreover, the proposed model utilizes a mobile agent that is transmitted from the user’s personal space, providing the user with complete control over their privacy protection. In addition, the mobile agent is itself a self-destructing program that eliminates the possibility of personal information being leaked. The mobile agent described in this paper allows users to truly control access to their personal information.