• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.8 s.99
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• pp.848-854
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• 2005

The attenuation due to rain has been recognized as one of the major causes of unavailability of radio communication systems operating above about 10 GHz. To design radio links for telecommunications and to evaluate attenuation due to rainfall, it is important to have a good prediction model for rain attenuation such as a model for drop-size distribution of rainfall(DSD), a theoretical model for specific rain attenuation, and an empirical model fur effective path length through rain. In this paper, the extended generalized gamma distribution for drop-size distribution, based on the measurements in Chnugnam National University, is proposed as a new DSD model, and predicted specific attenuation characteristics using proposed DSD model and rain attenuation values in the 44 GHz satellite path using ITU-R effective path length model, are analysed. The predicted attenuation levels are also compared. It is found that an accurate prediction method for DSD is very important to reduce the prediction error in the local satellite path.

• CELLMED
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• v.5 no.1
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• pp.3.1-3.3
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• 2015

Pharmacovigilance is the study of the safety of drugs under the practical conditions of clinical usage in large communities. Aim of this study was to assess the pharmacovigilance awareness among a focus group of Ayurveda physicians in Sri Lanka who participated for their postgraduate studies. A questionnaire which was suitable for assessing the basic knowledge, attitude and the practice of pharmacovigilance was designed and submitted among group of Ayurveda physicians (n = 30) who participated for postgraduate studies in Institute of Indigenous Medicine, University of Colombo, Sri Lanka. Among participants30% of the subjects knew the term pharmacovigilance, 20% were aware of the unavailability of the National Pharmacovigilance Program for Ayurveda and Traditional Medicine in Sri Lanka, 70% believe about Adverse Drug Reactions (ADRs) may be occurred from Ayurveda medicine, 60% indicated that Most labeled counterfeit drugs, inappropriate use and standardization problems as the most important causes of ADRs associated with Ayurvedicdrugs, 70% physicians accepted their ignorance about pharmacovigilance and admitted that there was a need for better training of this subject and 90% admitted that there should be a national pharmacovigilance programme for Ayurveda medicines in Sri Lanka. We strongly suggest that there is an urgent need for a regular training and the introduce ADRs reporting system among the Ayurveda physicians. Also systematic pharmacovigilance programme is essential to build up for reliable information on the safety and effective practice of Ayurveda medicine in Sri Lanka.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2901-2904
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• 2014

The incidence of colorectal cancer has been increasing in many Asian countries including Malaysia during the past few decades. A physician recommendation has been shown to be a major factor that motivates patients to undergo screening. The present study objectives were to describe the practice of colorectal cancer screening by primary care providers in Malaysia and to determine the barriers for not following recommendations. In this cross sectional study involving 132 primary care providers from 44 Primary Care clinics in West Malaysia, self-administered questionnaires which consisted of demographic data, qualification, background on the primary care clinic, practices on colorectal cancer screening and barriers to colorectal cancer screening were distributed. A total of 116 primary care providers responded making a response rate of 87.9%. About 21% recommended faecal occult blood test (FOBT) in more than 50% of their patients who were eligible. The most common barrier was "unavailability of the test". The two most common patient factors are "patient in a hurry" and "poor patient awareness". This study indicates that colorectal cancer preventive activities among primary care providers are still poor in Malaysia. This may be related to the low availability of the test in the primary care setting and poor awareness and understanding of the importance of colorectal cancer screening among patients. More awareness programmes are required for the public. In addition, primary care providers should be kept abreast with the latest recommendations and policy makers need to improve colorectal cancer screening services in health clinics.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.3
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• pp.514-522
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• 2015

In Microwave Radio Link, it is necessary to consider the radio fading to consistently assure the radio link of the high quality as the distance. If the fixed modulation is used for the microwave radio link, it is difficult to keep the high availability of link for the case of the long distance. Adaptive Modulation(AM) provide good quality on microwave link, but the application of the only-AM is not enough to provide the availability assurance due to the fluctuating characteristics of link capacity. Our previous study has proposed the improvement method of transmission in association with the distance, however the previous method needed to make up for the common application. There was no suggestion of a mathematical formula with a variable. In this paper, we propose an optimized Adaptive Transmission Techniques with calculating formula of the priority traffic transmission capacity based on AM in consideration of the fade margin for the availability assurance as the distance and the comparison of the channel bandwidth for Long-distance Radio Link.

• Proceedings of the KIEE Conference
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• 2006.05a
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• pp.74-77
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• 2006

This research is focused on the development of GIS Diagnostic SYSTEM to prevent accidents beforehand by inspecting the internal defects of GIS (Gas Insulated Switchgear) which is a main power-facility for substations. GIS Diagnostic SYSTEM is categorized as 'Real time on-line test type' and 'Portable test type' depending on the types of testing, it uses PD(partial discharge) which mostly incurs in GIS internal defects, to inspect. As of now, mostly foreign equipments are imported for use due to the lack of the technology localization, and these are installed and operated on only some parts of highly-graded GIS power-facilities such as in 76skv or 345kv for its being expensive. Furthermore, other than foreign equipments being costly, it also has a weak point of very long unavailability in case of Diagnostic system break-down while using, because it takes a comparatively long period of corrective maintenance precesses. We have localized to develop personal real-time multi -functional GIS Diagnostic system which can test on all GIS power-facility comprehensively and economically therefore overcome all these problems mentioned above, a market expansion is expected from the decrease of price and replacing the import equipments in the future. As the equipment was developed to be Personal for the simple ways of installing and utilizing, it can be operated without any complex cable installation like other existing GIS Diagnostic system requires, therefore also decrease the cost of cable installation.

• ALGAE
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• v.30 no.1
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• pp.35-47
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• 2015

The marine sand-dwelling dinoflagellate Polykrikos lebourae possesses obvious gold-brown pigmented plastids as well as taeniocyst-nematocyst complex structures. Despite of the presence of the visible plastids, previous attempts to establish this species in culture all failed and thus the unavailability of cultures of this species has posed a major obstacle to further detailed exploration of ecophysiology of the dinoflagellate. Here, we isolated P. lebourae from sandy sediment of an intertidal flat on Korean western coast, successfully established it in culture, and have been maintaining the stock culture over the past 3 years. Using this stock culture, we explored phagotrophy and potential prey resources of P. lebourae, growth and grazing responses of P. lebourae to different prey organisms, the effect of prey concentration on growth and grazing rates and gross growth efficiency (GGE) of P. lebourae when fed three different prey organisms, and the growth kinetics of P. lebourae under different light regimes. P. lebourae captured prey cells using a tow filament and then phagocytized them through the posterior end. The dinoflagellate was capable of ingesting a broad range of prey species varying in size, but not all prey species tested in this study supported its sustained growth. GGE of P. lebourae was extremely high at low prey concentration and moderate or low at high prey concentrations, indicating that P. lebourae grows heterotrophically at high prey concentrations but its growth seems to be more dependent on a certain growth factor or photosynthesis of plastids derived from the prey. In the presence of prey in excess, P. lebourae grew well at moderate light intensity of $40{\mu}mol$ photons $m^{-2}s^{-1}$, but did not grow at dim and high (10 or $120{\mu}mol$ photons $m^{-2}s^{-1}$) light intensities. Our results suggest that the benthic dinoflagellate P. lebourae is an obligate mixotroph, requiring both prey and light for sustained growth and survival.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.236-236
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• 2017

Low soil pH causes from $H^+$ rhizotoxicity results in nutrients unavailability in the growing media, inhibits plant growth, development and reduces crop yields. The present study was carried out to reveal morpholophysiological and biochemical responses of wheat (Triticum aestivum L.) to acidity stress. Four wheat varieties viz. BARI Wheat-21, BARI Wheat-25, BARI Wheat-26 and BARI Wheat-30 were used in the study. Eight-day-old seedlings were exposed to different pH levels (3.5, 4.5, 5.5 and 6.5) of growing media. Acidity stress at any level reduced biomass, water, and chlorophyll contents in all the varieties; whereas BARI Wheat-26 showed the least damage. $H^+$ rhizotoxicity also caused oxidative stress through excess production of reactive oxygen species and methylglyoxal which increase lipid peroxidation in all the varieties but the lowest oxidative damage was observed in BARI Wheat-26 due to better performance of the antioxidant defense and glyoxalase systems. Considering the growth, physiological and biochemical attributes BARI Wheat-26 may be considered as acidity stress tolerant, among the variety examined.

• Journal of Internet Computing and Services
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• v.15 no.1
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• pp.13-27
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• 2014

Agile methodologies have gained recognition as efficient development processes through their quick delivery of software, even under time constraints. However, like other agile methods such as Scrum, Extreme Programming (XP) and The Dynamic Systems Development Method (DSDM), Feature Driven Development (FDD) has been criticized due to the unavailability of security elements in its twelve practices. In order to examine this matter more closely, we conducted a systematic literature review (SLR) and studied literature for the years 2001-2012. Our findings highlight that, in its current form, the FDD model partially supports the development of secure software. However, there is little research on this topic, as detailed information about the usage of secure software is rarely published. Thus, we have been able to conclude that the existing five phases of FDD have not been enough to develop secure software until recently. For this reason, security-based phase and practices in FDD need to be proposed.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.451-457
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• 2011

Purple non-sulfur (PNS) bacterium $Rhodobacter$ $sphaeroides$ KD131 was studied with the aim of achieving maximum hydrogen production using various carbon and nitrogen sources at different pH conditions. Cells grew well and produced hydrogen using $(NH_4){_2}SO_4$ or glutamate as a nitrogen source in combination with a carbon substrate, succinate or malate. During 48h of photo-heterotrophic fermentation under 110$W/m^2$ illumination using a halogen lamp at $30^{\circ}C$, 67% of 30mM succinate added was degraded and the hydrogen yield was estimated as 3.29mol $H^2$/mol-succinate. However, less than 30% of formate was consumed and hydrogen was not produced due to a lack of genes coding for the formate-hydrogen lyase complex of strain KD131. Initial cell concentrations of more than 0.6g dry cell weight/L-culture broth were not favorable for hydrogen evolution by cell aggregation, thus leading to substrate and light unavailability. In a modified Sistrom's medium containing 30mM succinate with a carbon to nitrogen ratio of 12.85 (w/w), glutamate produced 1.40-fold more hydrogen compared to ammonium sulfate during the first 48h. However, ammonium sulfate was 1.78-fold more effective for extended cultivation of 96h. An initial pH range from 6.0 to 9.0 influenced cell growth and hydrogen production, and maintenance of pH 7.5 during photofermentation led to the increased hydrogen yield.

• The KIPS Transactions:PartC
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• v.10C no.1
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• pp.61-70
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• 2003

I-Business providers and customers have chosen the service availability as the most important technical parameter which should be included in their SLA to succeed in their business. This means that web Service availability management is crucial to the web-based service providers. Application availability is originally defined as a measure of the fraction of time during a defined period when the service provided is deemed to be better than user expectation of service performance. But, because most web service availability measurement tools simply monitor disconnected state, they do not satisfy user's expectation of extended availability concept. In this paper, We propose the web service availability measurement method which supports extended availability concept. It takes account of performance degradation of web service based on response time, and determines what is the cause of unavailability of the service. We developed a measurement tool, WebSerAvail.