• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.4
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• pp.325-332
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• 2002

In the process of designing pareto optimal insurance contract, it is necessary to assume that insurance contract conditions are endogenous to build a model. The expected utility, the non-expected utility and the state-dependent utility function can be applied as a insurance decision making principle. The insurance costs may have the linear, convex, and concave ralationship with the indemnity schedule. However, the sunk cost and fixed cost must be recognized. The deductible which decides whether an insurance contract to be a full or partial insurance contract can exist in the forms of straight deductible or diminishing deductible. Indeciding the level of deductible, the types of the insurance and the risks to be insured should be the deciding factors. Especially for recall insurance, there is relatively high chance that the recalling company being bankrupt. Therefore, the possibility of bankrupcy should be the considering factor in deciding the policy limit. The existence of the incomplete market and uninsurable background risk should be understood as restricting conditions of the pareto-optimal insurance contract.

• Journal of KIISE:Information Networking
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• v.28 no.4
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• pp.455-462
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• 2001

In this paper, we propose a deterministic algorithm to solve the resource discovery problem, that is, some subset of machines to learn the existence of each other in a large distributed network. Harchol et al. proposed a randomized algorithm solving this problem within O($log^2\;n$) rounds with high probability, which requires O($nlog^2\;n$) connection communication complexity and O($n^2log^2\;n$) pointer communication complexity, where n is the number of machines in the network. His solution is based on randomization method and it is difficult to determine convergence time. We propose an efficient algorithm which improve performance and the non-deterministic characteristics. Our algorithm requires O(log n) rounds which shows O(mlog n) connection communication complexity and O($n^2log\;n$) pointer communication complexity, where m is the number of links in the network.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.1
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• pp.45-51
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• 2014

Scuticociliates are regarded as serious pathogens in marine aquaculture worldwide. In Korea, they cause mass-mortalities in fish such as the commercially important olive flounder Paralichthys olivaceus. In particular, mixed infections of scuticociliates with pathogenic bacteria have been commonly reported. During efforts to identify natural marine-algae derived products that possess anti-bacterial and anti-scuticociliate properties, we found that an 80% methanolic extract of the red alga Polysiphonia morrowii Harvey exhibits both anti-scuticociliate activity against Miamiensis avidus, which is a major causative agent of scuticociliatosis, and anti-bacterial activities against fish pathogenic bacteria. Activity-guided fractionation and isolation of the 80% methanolic extract of P. morrowii yielded three bromophenols, which were identified as 3-bromo-4,5-dihydroxybenzyl methyl ether (1), 3-bromo-4,5-dihydroxybenzaldehyde (2) and urceolatol (3) based on spectroscopic analyses. 3-bromo-4,5-dihydroxybenzyl methyl ether (1) showed the highest anti-bacterial and anti-scuticociliate activities, with a minimal inhibitory concentration (MIC) of $62.5{\mu}g/mL$ (against Vibrio anguillarum) and minimal lethal concentration (MLC) of 62.5 ppm (in seawater). Investigations of the anti-bacterial and anti-scuticociliate activities of seventeen bromophenol derivatives, including the three isolated natural bromophenols, showed that the existence of an electron donating group or atom with a non-covalent electron pair at $C_4$ of the 2-bromophenol structure may be important in anti-scuticociliate activity. These findings suggest that the extract and bromophenol derivatives of P. morrowii may provide useful alternatives in aquaculture anti-scuticociliate therapies.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.3
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• pp.109-145
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• 2002

Council Directive 76/768/EEC forms the basis of the actual legislation of cosmetics in the European Union (EU). After a short introduction on the background and philosophy of this legislation, the key points will be discussed. In particular, attention will be given to the basic principles for safety and in this context the effects of the implementation of the 6th Amendment (Council Directive 93/35/EC) will be analysed. The major points for discussion will be: the safety requirements for cosmetics and the final responsibility for bringing these products on the EU market; the EU concept of safety of the finished product based on the safety of the individual ingredients; the existence of positive and negative lists of ingredients and the requirement for a European dossier for all finished products. Special attention will be given to the use of validated alternative methods and the consequences of the new proposal of a 7th Amendment. Finally, the safety evaluation as it is done by the SCCNFP (Scientific Committee on Cosmetics and Non-Food Products) in the case of an ingredient present on the positive lists and the evaluation done by a safety assessor in the case of a technical information file for a finished product, both will be discussed in detail.

• Smart Structures and Systems
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• v.14 no.3
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• pp.479-499
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• 2014

This paper illustrates the damages of reinforced concrete and masonry minarets during October 23 (Erciş) and November 9 (Edremit), 2011 Van earthquakes in Turkey. Erciş and Edremit are townships located 90km and 18km from Van city center in Turkey, respectively. Ground accelerations and response spectrums for these earthquakes are given in this paper. A total of 63 reinforced concrete and masonry minarets are heavily damaged or collapsed in the city center and villages nearby after both earthquakes. Because of the fact that there is no Turkish standard and specification directly related to design of minarets, nearly all of the constructions are carried out by workers using only their own technical knowledge. So, all of the non-engineering reinforced concrete and masonry minarets completely collapsed or damaged heavily. From the study, it is seen that the damages are due to several reasons such as site effect, location, and length of the fault, reduction in cross section and formation of the discontinuity, use of plain reinforcement steel, use of concrete with insufficient strength, existence of short lap splices and incorrect end hook angle, larger mass and stiffness concentrations on some region, longitudinal reinforcements discontinuity, cracks at the cylindrical body, and damage of spire and end ornament. In addition to these reasons, the two earthquakes hit the minarets within seventeen days, causing progressive damage. So, the existing design and construction practices should be improved to provide sufficient earthquake performance. Also, it is recommended that there should be a safe distance between the minaret and surrounding structures to reduce the loose of life after earthquake.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.314-323
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• 2010

Recently, granular soils having a large particle size are frequently used as a filling material in the construction of foundation, harbor, dam, and so on. The shear behavior of this granular soil plays a key role in the stability of structures. For example, soil particle crushing occurring at the interface between structure and soil and/or within soil mass can cause the disturbance of ground characteristics and consequently induce an issues in respect of stability of structures. In order to investigate the shear behavior according to an existence and nonexistence of particle crushing, numerical analyses were conducted by using the DEM(Discrete Element Method)-based software program PFC(Particle Flow Code). Using the crushing model and non-crushing model which were created in this study, numerical analyses of ring shear test were conducted and their results were analyzed and compared. In general, landslide and slope stability are accompanied by a large displacement and consequently not only a peak strength but also a residual strength are very important in the analysis of landslide and slope stability. However the direct shear test which has been commonly used in the determination of shear strength parameters has a limitation on displacement therefore the residual strength parameters can not be obtained. The characteristics of residual shear behavior were investigated through the numerical analyses in this study.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.1
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• pp.49-55
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• 2012

Asynchronous counters, where the counter value is changed not by a synchronizing clock but by outer inputs, are used in various modern digital systems such as spaceborne electronics. In this paper, we propose a scheme of fault tolerance for asynchronous counters with critical races caused by total ionizing dose (TID) in space. As a typical design flaw of asynchronous digital circuits, critical races cause an asynchronous circuit to show non-deterministic behavior, i.e., the next stable state of a state transition is not a fixed value but may be any value of a state set. Using the corrective control scheme for asynchronous sequential machines, this paper provides an existence condition and design procedure for a state feedback controller that can invalidate the effect of critical races. We implement the proposed control system in VHDL code and conduct experiments to demonstrate that the proposed control system can overcome critical races.

• Journal of Construction Engineering and Project Management
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• v.6 no.2
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• pp.8-15
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• 2016

Cost planning practices in the construction industry worldwide has gained much popularity in recent times due to economic recession and stringent measures that various procurement laws prescribe in most developed and developing countries. Nevertheless, these practices in developing countries such as Ghana are constrained with the existence of critical barriers that render them non-effective and hence, accounting for the numerous abandonment of both private and public projects. Consequently, this study was enunciated with the aim to examine the critical barriers to the practice of effective cost planning in the Ghanaian construction industry. Through an in-depth literature review and a pilot survey, questionnaires were designed and administered to quantity surveyors. Data generated from the field survey was subjected to principal component analysis. The findings of the study revealed weak cost planning knowledge base, poor cost databases and understanding, inadequate designs and planning and external conditions are the major barriers to cost planning practices in the Ghanaian construction industry. The need for this study cannot be doubted since it provides an insight for experts in the construction industry on the barriers of the practice of cost planning in the industry. The awareness of these barriers will therefore facilitate efficient and effective efforts to resolve them. A future study is thereby proposed by this study to explore effective cost planning practices in the Ghanaian construction industry that will ensure private and public stakeholders get value for their money invested.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.615-618
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• 2004

The piezoelectricity and polarization of multilayer ceramic actuators, being designed to stack ceramic layer and electrode layer alternately, were investigated under a consideration of geometry, the thickness ratio of the ceramic layer to electrode layer The actuators were fabricated by tape-casting of $0.42PbTiO_3-0.38PbZrO_3-0.2Pb(Mn_{1/3}Nb_{2/3})O_3$ followed by laminating, burn-out and co-firing process. The actuators of $5\times5mm^2$ in area were formed in a way that $60{\sim}200{\mu}m$ thick ceramics were stacked 10 times alternately with $5{\mu}m$ thick electrode. Increase in polarization and electric field-displacement with increasing thickness ratio of the ceramic/electrode layer and thickness/cross section ratio were attributed to the change of $non-180^{\circ}/180^{\circ}$ domain ratio which was affected by the interlayer internal stress and Poisson ratio of ceramic layer. The piezoelectricity and actuation behaviors were found to be dependent upon the volume ratio (or thickness ratio) of ceramic layer relative to ceramic layer. Concerning with the existence of internal stress, the field-induced polarization and deformation were described in the multilayer actuator.

• Journal of The Korean Astronomical Society
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• v.40 no.3
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• pp.67-82
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• 2007

The basic building block of solar filaments/prominences is thin threads of cool plasma. We have studied the spectral properties of velocity threads, clusters of thinner density threads moving together, by analyzing a sequence of $H{\alpha}$ images of a quiescent filament. The images were taken at Big Bear Solar Observatory with the Lyot filter being successively tuned to wavelengths of -0.6, -0.3, 0.0, +0.3, and +0.6 ${\AA}$ from the centerline. The spectra of contrast constructed from the image data at each spatial point were analyzed using cloud models with a single velocity component, or three velocity components. As a result, we have identified a couple of velocity threads that are characterized by a narrow Doppler width($\Delta\lambda_D=0.27{\AA}$), a moderate value of optical thickness at the $H{\alpha}$ absorption peak($\tau_0=0.3$), and a spatial width(FWHM) of about 1". It has also been inferred that there exist 4-6 velocity threads along the line of sight at each spatial resolution element inside the filament. In about half of the threads, matter moves fast with a line-of-sight speed of $15{\pm}3km\;s^{-1}$, but in the other half it is either at rest or slowly moving with a line-of-sight velocity of $0{\pm}3km\;s^{-1}$. It is found that a statistical balance approximately holds between the numbers of blue-shifted threads and red-shifted threads, and any imbalance between the two numbers is responsible for the non-zero line-of-sight velocity determined using a single-component model fit. Our results support the existence not only of high speed counter-streaming flows, but also of a significant amount of cool matter either being at rest or moving slowly inside the filament.