• Journal of Fisheries and Marine Sciences Education
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• v.16 no.2
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• pp.218-226
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• 2004

During the last two decades, the rapid increase in aquaculture world wide, particularly in finfish and shellfish culture, is the result of both area expansion and production intensification. Under these conditions, the prevalence and spread of infectious diseases have increased as a result of higher infection pressure and decreased resistance of the aquatic animals. Accordingly, the effective control of infectious diseases has become more and more important to development of aquaculture. Recently the Pathology Team of National Fisheries Research and Development(NFRDI), has played pivotal roles in establishing the national management and control system of aquatic animal health and disease by new legislative works and technical guidelines. Under the national aquatic animal disease control framework, the Pathology Team of NFRDI and MOMAF(Ministry of Maritime Affairs and Fisheries) should also establish effective management and regulations, with the support of enforcement and monitoring policies. In conjunction with effective aquatic disease national management, financial assistance or alternative compensation options for aquaculture should also be available in the event of production losses or eradication system.

• Nuclear Engineering and Technology
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• v.52 no.5
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• pp.1079-1092
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• 2020

A parametric study of several parameters relevant to design safety on the spent nuclear fuel (SNF) rod response under a drop accident is presented. In the view of the complexity of interactions between the independent safety-related parameters, a factorial design of experiment is employed as an efficient method to investigate the main effects and the interactions between them. A detailed single full-length fuel rod is used with consideration of post-irradiated fuel conditions under horizontal and vertical free-drops onto an unyielding surface using finite-element analysis. Critical drop heights and critical g-loads that yield the threshold plastic strain in the cladding are numerically estimated to evaluate the fuel rod structural resistance to impact load. The combinatory effects of four uncertain parameters (pellet-cladding interfacial bonding, material properties, spacer grid stiffness, rod internal pressure) and the interactions between them on the fuel rod response are investigated. The principal finding of this research showed that the effects of above-mentioned parameters on the load-carrying capacity of fuel rod are significantly different. This study could help to prioritize the importance of data in managing and studying the structural integrity of the SNF.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3196-3206
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• 2021

For the Korean design of the PCCS (passive containment cooling system) in an innovative PWR, the overall thermal resistance around a condenser tube is dominated by the heat transfer coefficient of steam condensation on the exterior surface. It has been reported, however, that the calculated heat transfer coefficients by thermal-hydraulic system codes were much lower than measured data in separate effect tests. In this study, a new empirical model of steam condensation in the presence of a noncondensable gas was implemented into the MARS-KS 1.4 code to replace the conventional Colburn-Hougen model. The selected correlation had been developed from condensation test data obtained at the JERICHO (JNU Experimental Rig for Investigation of Condensation Heat transfer On tube) facility, and considered the effect of the Grashof number for naturally circulating gas mixture and the curvature of the condenser tube. The modified MARS-KS code was applied to simulate the transient response of the containment equipped with the PCCS to the large-break loss-of-coolant accident. The heat removal performances of the PCCS and corresponding evolution of the containment pressure were compared to those calculated via the original model. Various thermal-hydraulic parameters associated with the natural circulation operation through the heat transport circuit were also investigated.

• Corrosion Science and Technology
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• v.18 no.1
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• pp.33-38
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• 2019

Alloy 600/182 with excellent mechanical/chemical properties have been utilized for nuclear power plants. Although both alloys are known to have superior corrosion resistance, stress corrosion cracking failure has been an issue in primary water environment of nuclear power plants. Therefore, primary water stress corrosion crack (PWSCC) growth rate tests were conducted to investigate crack growth properties of Alloy 600/182. To investigate PWSCC growth rate, test facilities including water chemistry loop, autoclave, and loading system were constructed. In PWSCC crack growth rate tests, half compact-tension specimens were manufactured. These specimens were then placed inside of the autoclave connected to the loop to provide primary water environment. Tested conditions were set at temperature of $360^{\circ}C$ and pressure of 20MPa. Real time crack growth rates of specimens inside the autoclave were measured by Direct Current potential drop (DCPD) method. To confirm inter-granular (IG) crack as a characteristic of PWSCC, fracture surfaces of tested specimens were observed by SEM. Finally, crack growth rate was derived in a specific stress intensity factor (K) range and similarity with overseas database was identified.

• Wind and Structures
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• v.28 no.3
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• pp.155-170
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• 2019

This paper presents a novel test method for the galloping of iced conductor using wind generated by a moving vehicle which can produce relative wind field. The theoretical formula of transiting test is developed based on theoretical derivation and field test. The test devices of transiting test method for aerodynamic coefficient and galloping of an iced conductor are designed and assembled, respectively. The test method is then used to measure the aerodynamic coefficient and galloping of iced conductor which has been performed in the relevant literatures. Experimental results reveal that the theoretical formula of transiting test method for aerodynamic coefficient of iced conductor is accurate. Moreover, the driving wind speed measured by Pitot tube pressure sensors, as well as the lift and drag forces measured by dynamometer in the transiting test are stable and accurate. Vehicle vibration slightly influences the aerodynamic coefficients of the transiting test during driving in ideal conditions. Results of transiting test show that the tendencies of the aerodynamic coefficient curve are generally consistent with those of the wind tunnel tests in related studies. Meanwhile, the galloping is fairly consistent with that obtained through the wind tunnel test in the related literature. These studies validate the feasibility and effectiveness of the transiting test method. The present study on the transiting test method provides a novel testing method for research on the wind-resistance of iced conductor.

• Nuclear Engineering and Technology
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• v.50 no.7
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• pp.1079-1087
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• 2018

There are many parameters that affect the natural circulation flow, such as height difference, heating power size, pipe diameter, system pressure and inlet temperature and so on. In general analysis the heating power is often regarded as a uniform distribution. The ANSYS-CFX numerical analysis software was used to analyze the flow heat transfer of supercritical water under different heating power distribution conditions. The distribution types of uniform, power increasing, power decreasing and sine function are investigated. Through the analysis, it can be concluded that different power distribution has a great influence on the flow of natural circulation if the total power of heating is constant. It was found that the peak flow of supercritical water natural circulation is maximal when the distribution of heating power is monotonically decreasing, minimal when it is monotonically increasing, and moderate at uniform or the sine type of heating. The simulation results further reveal the supercritical water under different heat transfer conditions on its flow characteristics. It can provide certain theory reference and system design for passive residual heat removal system about supercritical water.

• Biomolecules & Therapeutics
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• v.29 no.1
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• pp.11-21
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• 2021

Adipose tissue secretes many adipokines which contribute to various metabolic processes, such as blood pressure, glucose homeostasis, inflammation and angiogenesis. The biology of adipose tissue in an obese individual is abnormally altered in a manner that increases the body's vulnerability to immune diseases, such as psoriasis. Psoriasis is considered a chronic inflammatory skin disease which is closely associated with being overweight and obese. Additionally, secretion of leptin, a type of adipokine, increases dependently on adipose cell size and adipose accumulation. Likewise, high leptin levels also aggravate obesity via development of leptin resistance, suggesting that leptin and obesity are closely related. Leptin induction in psoriatic patients is mainly driven by the interleukin (IL)-23/helper T (Th) 17 axis pathway. Furthermore, leptin can have an effect on various types of immune cells such as T cells and dendritic cells. Here, we discuss the relationship between obesity and leptin expression as well as the linkage between effect of leptin on immune cells and psoriasis progression.

• The Southeast Asian review
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• v.22 no.2
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• pp.171-199
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• 2012

Saman, a novel written by Ayu Utami, has been recognized as the symbol of the politico-social changes, which began to occur since the collapse of Suharto' New Order regime in 1998. In the novel, Ayu Utami showed the spirits of resistance against various absurd socio-political circumstances during the New Order era such as pressure on discussion, abuse of power, politics-business collusion, patriarchism, and suppression of gender. In representing those spirits, Ayu Utami used unconventional structure-making, fresh feedback and multilayered descriptions of the figures, which brought her a fame as the pioneer of the Fragrant Literature (Angkatan Wangi or chick-lit). Ayu Utami particularly criticized that, under the name of sustaining the national integrity and identity, the New Order regime enhanced patriarchal system, which consequently infringed gender equality and women's rights to self-determination. In addition, Ayu Utami argued that the abuse of power and politics-business collusion, which were prevalent during the New Order period, destroyed lives of the masses and the Indonesian society.

• Journal of the Korean Society of Safety
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• v.36 no.4
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• pp.1-11
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• 2021

Piping systems comprising pumps and valves are essential in the power plant, oil, and defense industry. Their purpose includes a stable supply of the working fluid or ensuring the target system's safe operation. However, piping system accidents due to leakage of toxic substances, explosions, and natural disasters are prevalent In addition, with the limited maintenance personnel, it becomes difficult to detect, isolate, and reconfigure the damage of the piping system and recover the unaffected area. An autonomous recovery piping system can play a vital role under such circumstances. The autonomous recovery algorithms for the piping system can be divided into low-pressure control algorithms, hydraulic resistance control algorithms, and flow inventory control algorithms. All three methods include autonomous opening/closing logic to isolate damaged areas and recovery the unaffected area of piping systems. However, because each algorithm has its strength and weakness, appropriate application considering the overall design, vital components, and operating conditions is crucial. In this regard, preliminary research on algorithm's working principle, its design procedures, and expected damage scenarios should be accomplished. This study examines the characteristics of algorithms, the design procedure, and working logic. Advantages and disadvantages are also analyzed through simulation results for a simplified piping system.

• Korean Journal of Materials Research
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• v.32 no.4
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• pp.230-236
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• 2022

The formation behavior of a passive state film on the surface of STS304 in electrolytic solution was analyzed to determine its metallic ion composition. The properties of passive state films vary depending on the Fe and Cr ions in the electrolytic solution. It was observed that the passive state film surface became flat and glossy as the concentration of Fe and Cr ions in the electrolytic solution increased. The corrosion resistance property of the passive state film was proportional to the amount of Fe and Cr in the electrolytic solution. An initial passive state film with high Fe concentration was formed on the surface of STS304 during early electrolytic polishing. Osmotic pressure of Fe ions occurs between the passive state film and electrolytic solution due to the Fe ion concentration gradient. The Fe in the passive state film is dissolved into the electrolyte, and Cr fills up the Fe ion vacancies. As a result, a good corrosion-resistant floating film was formed. The more Fe ions in the electrolytic solution, the faster the film is formed, and as a result, a flat passive state film containing a large amount of Cr can be formed.