• Mass Spectrometry Letters
• /
• v.5 no.2
• /
• pp.42-48
• /
• 2014

A specific and sensitive liquid chromatography-electrospray ionization tandem mass spectrometry method (LC-ESI-MS/MS) was developed and validated for the simultaneous quantification of porphyrins (coproporphyrin, pentacarboxylporphyrin, hexacarboxylporphyrin, heptacarboxylporphyrin, and uroporphyrin) in human plasma and urine. Acidified plasma samples and urine samples were prepared by using liquid-liquid extraction using ethyl acetate and protein precipitation with acetonitrile, respectively. The separation was achieved onto a Synergi Fusion RP column ($150mm{\times}2.0mm$, $4{\mu}m$) with a gradient elution of mobile phase A (0.1% formic acid in 2 mmol/L ammonium acetate, v/v) and mobile phase B (20% methanol in acetonitrile, v/v) at a flow rate of $450{\mu}L$/min. Porphyrins and the internal standard (IS), coproporphyrin I-$^{15}N_4$, were detected by a tandem mass spectrometer equipped with an electrospray ion source operating in positive ion mode. Multiple reaction monitoring (MRM) transitions of the protonated precursor ions and the related product ions were optimized to increase selectivity and sensitivity. The proposed method was validated by assessing selectivity, linearity, limit of quantification (LOQ), precision, accuracy, recovery, and stability. The calibration curves were obtained in the range of 0.1-100 nmol/L and the LOQs were estimated as 0.1 nmol/L for all porphyrins. Results obtained from the validation study of porphyrins showed good accuracy, precision, recovery, and stability. Finally, the proposed method was successfully applied to clinical studies on the autism spectrum disorder (ASD) diagnosis of 203 Korean children.

• Architectural research
• /
• v.12 no.2
• /
• pp.73-83
• /
• 2010

Aging is accompanied with numerous transitions in life, and residential environment becomes a pivotal part of the elderly's lives. Physically supportive housing linked with services emerges in midst of the reality that retrofitting housing with special features has been seriously underfunded. The purpose of this study was to examine the residential satisfaction of the elderly in two types of independent living arrangements specially designed for the elderly. The indices of residential supportiveness were developed, and the questionnaire survey was adopted for data collection. Two hundred eighty residents living in two different kinds of senior housing participated in the survey, and all the collected responses were used for data analysis. The finding showed that almost all of the elderly positively assessed their senior living. That is, the statistical analysis illustrated that satisfaction indices of senior living significantly and positively contributed the satisfaction with overall residential environment. Satisfaction with physical environment was the only strong predictor in explaining current residential satisfaction of the elderly in senior rental housing, and accounted for a small proportion of the variance in the dependent variable. Since affordability was the biggest concern among residents in senior housing, it was of significance that long-term housing affordability was ensured and reduction in service cost by utilizing economies of scale was pursued.

• Journal of Korean Academy of Nursing
• /
• v.42 no.7
• /
• pp.1019-1026
• /
• 2012

Purpose: To examine geographical imbalances by analyzing new graduate nurses' migration patterns among regions where they grew up, attended nursing school, and had their first employment and to identify factors related to working in non-metropolitan areas. Methods: The sample consisted of 507 new graduates working in hospitals as full-time registered nurses in South Korea. Migration patterns were categorized into 5 patterns based on sequential transitions of "geographic origin-nursing school-hospital." Multiple logistic regression analysis was conducted to identify factors associated with working in non-metropolitan hospitals. Results: Nurses who grew up, graduated, and worked in the same region accounted for the greatest proportion (54%). Sixty-five percent had their first employment in the region where they graduated. Nurses tended to move from poor to rich regions and from non-metropolitan to metropolitan areas. Working in non-metropolitan hospitals was related to older age, the father having completed less than 4 years of college education, non-metropolitan origin, non-capital city school graduation, and a diploma (vs. baccalaureate) degree. Conclusion: Admitting students with rural backgrounds, increasing rural nursing school admission capacities, and providing service-requiring scholarships, particularly for students from low-income families, are recommended to address geographical imbalances.

• The Journal of the Korea Contents Association
• /
• v.2 no.3
• /
• pp.119-126
• /
• 2002

The QoS(Quality of Service) guarantee mechanism is one of critical issues in the wireless network. Real-time applications like VoIP(Voice over IP) in All-IP networks need smooth handoffs in order to minimize or eliminate packet loss as a Mobile Host(MH) transitions between network links. In this paper, we design a new multicasting algorithm using DB(Dynamic Buffering) mechanism for Mobile-IPv6. A key feature of the new protocol is the concepts of the DB and MRA(Multicast Routing Agent) to reduce delivery path length of the multicast datagram. Particularly, the number of tunneling and average routing length of datagram are reduced relatively, the multicast traffic load is also decreased.

• Korean Institute of Interior Design Journal
• /
• no.18
• /
• pp.31-37
• /
• 1999

This study aims to provide architectural basis of the new space planning in university library and anticipate direction in future. This study is to analyze the spatial transition in the existing facility, based on field observation of the domestic university library and on theoretical data from the related article. The result that include a transition of the existing facility and the present is as following as below. 1) Spatial transitions by networking are making specific system room. The minimum area of this specific system room is 33.95$m^2$. 2) Spatial transition by information service is forming computer room. the minimum area of a environmental carrel, which is possibly located to computer room, is 2.98~3.42$m^2$. 3) Spatial transition by spreading multimedia information is to make the multimedia information is to make the multimedia room. It is necessary to independent, flexibility, and extensionable space. 4) Library interior spatial transition by developing information technology is prospected that in case of reading room, office enlarge the scale, in case of stack decrease the scale. The university library must be kept up their function and also be functioned as electronic library which serve new information.

• SUVANNABHUMI
• /
• v.14 no.2
• /
• pp.27-59
• /
• 2022

During the past two decades, the Southeast Asian region has experienced a range of major crises. Service industries such as tourism and the marginal and migrant laborers who work in them have usually been at the sharp end of these testing events, from natural and environmental disasters, epidemics and pandemics, global financial slumps, terrorism, and political conflict. The latest challenge is the "Novel Coronavirus" (Covid-19/SARS-CoV-2) pandemic. It has already had serious consequences for Southeast Asia and its tourism development and these will continue for the foreseeable future. Since the SARS epidemic of 2002-2004, Southeast Asian economies have become integrated increasingly into those of East Asia (China, Japan, South Korea, Taiwan, Hong Kong). This paper examines one of the most significant current crises, Covid-19, and its consequences for Southeast Asia, its tourism industry, and its workers, comparing experiences across the region, and the issues raised by the over-dependence of some countries on East Asia. In research on crises, the main focus has been on dramatic, unpredictable natural disasters, and human-generated global economic downturns. Not so much attention has been devoted to disease and contagion, which has both natural and socio-cultural dimensions in origins and effects, and which, in the case of Covid-19, evoke a pre-crisis period of normality, a liminal transition or "meantime" and a post-crisis "new normality." The transition is not straightforward; in many countries, it operates as a set of serial lockdowns and restrictions, and to predict an uncertain future remains difficult.

• The Journal of the Korean dental association
• /
• v.48 no.1
• /
• pp.6-11
• /
• 2010

Amid the rapid transitions in both local and international markets, the Korean dental industry is facing more challenges than at any time in its history. This paper tried to address some of the key issues faced by the industry as well as the policy issues and I direction of implementation that the Korean Dental Association (KDA) is expected to tackle. First, the direction of reforming the country's health insurance system was examined with emphasis on the expected changes in and improvement of the fee-for-service reimbursement system (FFSRS) and medical reimbursement system (MRS). With FFSRS, the most urgent issue would be ameliorating the current lop-sided, unreasonable reimbursement system that prevents suppliers from voicing their opinions. To help achieve that goal, the limited authority and responsibility of the president of National Health Insurance Corporation (NHIC) as one of the contract-making parties must be clarified. In addition, the functions of NHIC's Health Insurance Finance Committee must be restricted; at the same time, the panel organization of the Health Insurance Policy Review Committee needs to be reformed to embrace greater democracy. As with MRS, the government is considering a block budget bill to help promote efficiency in employing and managing the health insurance fund. Policymakers must understand that the implementation of such proposal could exacerbate an already dire situation. Improving MRS requires meeting the following preconditions: (a) the structurally vicious cycle of small charge-small salary needs to be resolved, and a certain percentage of fee raise must be guaranteed on a yearly basis to help adjust the fee system to a more realistic level; (b) the supply-and-demand balance in producing health care professionals must be improved including the prevention of oversupply of doctors, nurses, etc., and; (c) institutional strategies must be provided to enhance the quality of medical care and ensure academic advancement in health care disciplines.

• Journal of Korea Multimedia Society
• /
• v.9 no.11
• /
• pp.1503-1514
• /
• 2006

Today, consumers can access Internet from everywhere, therefore most commercial and other organizations provide their services on the Web. As the result, countless Web service systems are already on the Internet and more systems are under construction. Therefore, many researches of verifying that the system to be constructed will not have any deadlock and will run successfully without any problem at the early stage of design have been performed. Several Petri net based verification methods have also been published. However, they have focused on building Petri net models of Web service systems and none of them introduces efficient analysis methods. As a mathematical technique with which we can find the minimum duration time needed to fire all the transitions at least once and coming back to the initial marking in a timed net, the minimum cycle time method has been widely used in computer system analysis. A timed net is a modified version of a Petri net where a transition is associated with a delay time. A delay time used in a timed net is a constant even though the duration time associated with an event in the real world is a stochastic number in general. Therefore, this paper proposes 'Mixedly Distributed Stochastic Timed Net' where a transition can be associated with a stochastic number and introduce a minimum cycle time analysis method for 'Mixedly Distributed Stochastic Timed Net'. We also introduce a method of analysing a Web service system's response time with the minimum cycle time analysis method for 'Mixedly Distributed Stochastic Timed Net.'.

• Analytical Science and Technology
• /
• v.20 no.2
• /
• pp.138-146
• /
• 2007

A simple and sensitive method for the determination of paroxetine in canine plasma was developed and validated by liquid-liquid extraction and liquid chromatography-tandem mass spectrometry (LC-/MS/MS). Fluoxetine was used as an internal standard. Paroxetine and internal standard in plasma samples were extracted using TBME (tert-butyl methyl ether). A centrifuged upper layer was then evaporated and reconstituted with mobile phase of 50% acetonitrile adjusted to pH 3 by formic acid. The reconstituted samples were injected into a Capcell Pak UG120 ($2.0{\times}150mm$, $5{\mu}m$) column. Using MS/MS with SRM (selective reaction monitoring) mode, the transitions (precursor to product) monitored were m/z $330{\rightarrow}192$ for paroxetine, and m/z $310{\rightarrow}148$ for internal standard. Linear detection responses were obtained for paroxetine concentration range of 0.02~5 ng/mL. A correlation coefficient of linear regression ($R^2$) was 0.9993. Detection of paroxetine in canine plasma was accurate and precise, with limit of quantification at 0.02 ng/mL. The method has been successfully applied to pharmacokinetic study of paroxetine in healthy beagle dogs.

• Journal of IKEEE
• /
• v.13 no.2
• /
• pp.159-166
• /
• 2009

So far, many researches have been done to retrieve music information using static classification descriptors such as genre and mood. Since static classification descriptors are based on diverse content-based musical features, they are effective in retrieving similar music in terms of such features. However, human emotion or mood transition triggered by music enables more effective and sophisticated query in music retrieval. So far, few works have been done to evaluate the effect of human mood transition by music. Using formal representation of such mood transitions, we can provide personalized service more effectively in the new applications such as music recommendation. In this paper, we first propose our Emotion State Transition Model (ESTM) for describing human mood transition by music and then describe a music classification and recommendation scheme based on the ESTM. In the experiment, diverse content-based features were extracted from music clips, dimensionally reduced by NMF (Non-negative Matrix Factorization, and classified by SVM (Support Vector Machine). In the performance analysis, we achieved average accuracy 67.54% and maximum accuracy 87.78%.