• Journal of the Korean Geographical Society
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• v.49 no.1
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• pp.45-56
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• 2014

Data composite methods have been typically applied to satellite-based vegetation index(VI) data to continuously acquire vegetation greenness over the land surface. Data composites are useful for construction of long-term archives of vegetation indices by minimizing missing data or contamination from noise. In addition, if multi-sensor vegetation indices that are acquired during the same composite periods are used interchangeably, data stability and continuity may be significantly enhanced. This study evaluated the influences of sensor geometry on MODIS vegetation indices and investigated data compatibility of two difference vegetation indices, the Normalized Difference Vegetation Index(NDVI) and the Enhanced Vegetation Index(EVI), for potential improvement of long-term data construction. Relationships between NDVI and EVI turned out statistically significant with variations among vegetation covers. Due to their curvilinear relationships, NDVI became saturated and leveled off as EVI reached high ranges. Correlation coefficients between Terra- and Aqua-based vegetation indices ranged from 0.747 to 0.963 for EVI, and from 0.641 to 0.880 for NDVI, showing better compatibility for EVI compared to NDVI. In-depth analyses of VI outliers that deviated from regression equations constructed from the two different sensors remain as a future study to improve their compatibility.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.367-381
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• 2003

Dispersal polymorphism in insects Is a kind of adaptive strategy of the life history together with the diapause, consisting of the “long-winged or alate forms” of migratory phase and the “short-winged or apterous forms” of stationary phase. Dispersal polymorphism is a polymorphism related with the flight capability, and has three categories ; the wing polymorphisms, flight muscle polymorphisms, and flight behavior variations. Phase variation is another type of dispersal polymorphism varying in morphology, physiology and wing forms in response to the density of the population. The dispersal migration is a very adaptive trait that enables a species to keep pace with the changing mosaic of its habitat, but requires some costs. In general, wing reduction has a positive effect on the reproductive potential such as earlier reproduction and larger fecundity The dispersal polymorphism is a kind of optimization in the evolutionary strategies of the life history in insects; a trade-off between the advantages and disadvantages of migration. Wing polymorphism is a phenotypically plastic trait. Wing form changes with the environmental conditions even though the species is the same. Various environmental factors have an effect on the dispersal polymorphisms. Density dependent dispersal polymorphism plays an important role In population dynamics, but it is not a simple function of the density; the individuals of a population may be different in response to the density resulting different outcomes in the population biology, and the detailed information on the genotypic variation of the individuals in the population is the fundamental importance in the prediction of the population performances in a given environment. In conclusion, the studies on the dispersal polymorphisms are a complicated field in relation with both physiology and ecology, and studies on the ecological and quantitative genetics have indeed contributed to understanding of its important nature. But the final factors of evolution; the mechanisms of natural selections, might be revealed through the studies on the population biology.

• Investigative Magnetic Resonance Imaging
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• v.4 no.1
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• pp.14-19
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• 2000

Purpose : This study was to present the functional brain mapping of both functional magnetic resonance imaging(MRI) and transcranial magnetic stimulation(TMS) in a case of schizencephaly. Materials and methods : A 28-year-old man, who had left hemiplegia and schizencephaly in right cerebral hemisphere, was exacted with both functional MRI and TMS. Motor function of left hand was decreased whereas right hand was within normal limit. For functional MRI, gradient-echo echo planar imaging($TR/TE/{\alpha}$=1.2 sec/90 msec/90) was employed. The paradigm of motor task consisted of repetitive self-paseo hand flexion-extension exercises with 1-2 Hz periods. An image set of 10 slices was repetitively acquired with 15 seconds alternating periods of task performance and rest and total 6 cycles (three ON periods and three OFF periods) were performed. In brain mapping, TMS was performed with the round magnetic stimulator (mean diameter; 90mm). The magnetic stimulation was done with 80% of maximal output. The latency and amplitude of motor evoked potential(MEP)s were obtained from both abductor pollicis brevis(APB) muscles. Results : Functional MRI revealed activation of the left primary motor cortex with flexion-extension exercises of healthy right hand. On the other hand, the left primary motor cortex, left supplementary motor cortex, and left promoter areas were activated with flexion-extension exercises of left hand. In TMS, magnetic evoked potentials were induced in no areas of right cerebral hemisphere, but in 5 areas of left corebral hemisphere from both abductor pollicis brevis. Latency, amplitude, and contour of response of the magnetic evoked potentials in both hands were similar. Conclusion : Functional MRI and TMS in a patient with schizencephaly were successfully used to localize cortical motor function. Ipsilateral motor pathway is thought to be secondary to reinforcement of the corticospinal tract of the ipsilateral motor cortex.

• Korean Journal of Biological Psychiatry
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• v.20 no.3
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• pp.111-117
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• 2013

Objectives We investigated the effectiveness and safety when treated in schizophrenics with paliperidone palmitate, a long acting injectable antipsychotic. Methods This was a 24-week open-label study, performed at one center in Korea. The eligible patients with schizophrenia diagnosed by Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) criteria were enrolled. Patients received long-acting paliperidone palmitate injection (234 mg, baseline; 156 mg, week 1 ; then once 4 weeks flexible dosing). Effectiveness assessments were measured by the Positive and Negative Syndrome Scale (PANSS), The Clinical Global Impression Severity Scale (CGI-S), The Personal and Social Performance (PSP) at baseline, week 1, every 4 weeks untill 24 weeks or endpoint. Safety assessments were measured by The Extrapyramidal Symptom Rating Scale (ESRS), body weight (BW) and incidence of adverse events. Oral antipsychotics were stopped or tapered off within next 14 days. Results Of 20 patients recruited, 9 patients (45%) completed the study. Paliperidone palmitate produced a significant improvement in PANSS total score from baseline to endpoint. The response rate was 75% [mean change (${\pm}SD$) $-25.9{\pm}14.4$, all p < 0.001]. The CGI-S and PSP total scores significantly improved during 24 weeks (All p < 0.001). Eighty percent of patients reported adverse events and most common adverse events (${\geq}10%$) in paliperidone palmitate were anticholinergic adverse event, extrapyramidal symptoms, weight gain, akathisia, insomnia, headache, agitation, anxiety and GI trouble. ESRS score is not statistically significant, but tends to get better at the end of the study when compared to baseline. Conclusions Our study results demonstrated maintained effectiveness and safety of paliperidone palmitate treatment in schizophrenics. And provides both clinicians and patients with a new choice of treatment that can improve the outcome of long term therapy. Their potential effectiveness and safety should be better addressed by future randomized-controlled trials.

• Fire Science and Engineering
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• v.15 no.1
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• pp.84-92
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• 2001

In today's world, rise in the establishment of social infrastructure resulting from population saturation in large cities has led to more extensive and frequent use of chemical materials on facilities. A result, unexpected and serious accidents, hazards, contingencies and disasters are more prevalent than ever. Such phenomenon calls for more devoted and concerted efforts towards finding ways to reduce the safety hazards that are seen to take place more often than before with the increase in the number of facilities that are prone to bring disaster and hazard coupled with the conventional safety problems that continue to exist even today. In developed countries, such challenge is addressed by various appropriate countermeasures drawn up by local professional committees on industrial facilities, whose members conduct offsite and onsite evaluation un the potential industrial disasters and its seriousness and provide their advice thereof. Against this backdrop, this study aims at identifying a comprehensive safety allowance level (safety acceptable level) when imposing limitation on the development of conventional or new facilities, for the fur pose of establishing a safety allowance level of disastrous and dangerous facilities in Korea. This is done by assessing and applying the level of danger each individual is exposed to in a randomly selected region (disastrous and dangerous areas in Seoul) based on probability of quantitative hazards, as well as simulation and calculation methods which include: i) social disaster evaluation method applying Quantified Risk Assessment of Health & Safety Executive of UK and Matrix of Risk of Evaluated Sources of Hazard; ii) Fault Tree or Event Tree Analysis and etc.

• Management & Information Systems Review
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• v.23
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• pp.25-40
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• 2007

In the highly competitive and divers world of financial market, customer is the single most important factor to company's survival. Especially, creating a relationship with valued customers is a key to success. CRM provides the mean to retain high value customers. It takes a prospect of what customers expect. Utilizing those knowledge can help the products and service meet the customers' needs, thereby maximizing customer satisfaction and company's profit. In this report, I am going to suggest a few ways to develop successful CRM in the life insurance industry. First, CRM should innovate the way of communication to keep pace with Web 2.0 era. In other words, the customer's needs should be caught by real-time communication than traditional off-line market research. Thus, the functionality and specification of products can be decided by customer's direct choice so that the customers are able to purchase the understanding and experience of the products. Second, CRM project should consider whether the initial strategy plan can promise the stable growth of customer at the first step. When planning strategy, the project needs to identify what customer wants and how to fulfill the needs with stable growth of the customer. In addition, the CRM should be developed by realizing that customer centric benefits ultimately guarantee the growth of the organization. Third, CRM systems should enhance the organization's ability to take the customer's insight in a 360 degree view and to capture the voice of the customer directly. In order to develop the best matched product package, more precise customer segmentation should be ahead of market segmentation strategy. Forth, the biggest reward from CRM will be a customer royalty program. Many successful banks are already planning and practicing customer royalty strategy. A comprehensive analysis of customers and their behavior allow organization to identify high value potential customers' needs and determine a strategy required to meet those needs. Even life insurance companies such as Prudential Korea are developing products designed for royal customers. Fifth, understanding and managing the experience of customer called Customer Experience Management also can increase customer satisfaction. Measuring only customers' experience and adapting it to marketing strategy make products position in the gap between the customers' expectation and experience not required by market. A key component of CEM is its application across all organizational functions. At last, the direction of change and development of CRM can be defined from the conceptualization of information technology represented by Ubiquitous and Web 2.0. Instead of just managing customer information, companies should take the initiative in personalized system with customer oriented strategy. Furthermore, with the regular communication between CRM stakeholders (Sales-Marketing-IT), customer's demand should be directly reflected to enterprise strategy in real time.

• Korean Journal of Environment and Ecology
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• v.29 no.5
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• pp.681-692
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• 2015

It is well documented that physiological and nutritional condition of wintering birds is strongly related to migration success to breeding sites, and also breeding success. However, how abiotic factors during winter affect the migration and breeding successes still remains unclear. Thus, this study developed a dynamic-state-dependent model for wintering life-history to identify the potential impact on the life-history, success to breeding site and breeding success of wintering birds, which are related to temperature fluctuation, interspecific competition and human disturbance at the wintering sites. To find the best-fit-model, we referred to the existing research data on wintering ecology of Red-crowned cranes (Grus japonensis) in Cheolwon, Korea, which is well documented as a long-term wintering study. Our model predicted that the higher temperature fluctuation and a higher rate of human disturbance are negatively related to migration success to breeding sites and their fitness, ultimately breeding success via changing of proportion in resource allocation (for e. g., lower energy compensation or higher level of stress accumulation). Particularly, the rate of body mass compensation after arrival at wintering sites may be accelerated when there are less temperature fluctuations and a lower rate of human disturbance. In addition, the rate of interspecific competition sharing the wintering foraging sites is negatively related to the rate of body mass compensation. Consequently, we discussed the conservation strategies of wintering birds based on the outcomes of the model.

• Journal of Sensor Science and Technology
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• v.1 no.1
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• pp.67-75
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• 1992

PTC thermistor has been fabricated with as-received $BaTiO_{3}$ powder and its electrical properties were investigated. The resistivity of the PTC thermistor was measured at $20^{\circ}C$ intervals from $20^{\circ}C$ to $200^{\circ}C$. The electrical characteristics of the PTC thermistor are determined by the ac complex impedance analysis. The average grain size measured with a scanning electron microscope increased from $3.8{\mu}m$ to $8.8{\mu}m$ with increasing sintering temperature between $1280^{\circ}C$ and $1400^{\circ}C$. The maximum resistivity jump was $4{\times}10^{5}$. The bulk resistivity of the thermistor sintered above $1340^{\circ}C$ decreased with increasing temperature of the measurement. The grain boundary resistance increased exponentially, the grain boundary capacitance decreased, and the built-in potential at the grain boundary increased with increasing temperature of the measurement. The charge densiy at the grain boundary increased with increasing temperature up to $110^{\circ}C$, which leveled off with further increase in measuring temperature.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.12
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• pp.1-7
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• 2008

Magnetic Tunneling Junction (MTJ) has been used as a nonvolatile universal storage element mainly in memory technology. However, according to several recent studies, magneto-logic using MTJ elements show much potential in substitution for the transistor-based logic device. Magneto-logic based on MTJ can maintain the data during the power-off mode, since an MTJ element can store the result data in itself. Moreover, just by changing input signals, the full logic functions can be realized. Because of its programmability, it can embody the reconfigurable magneto-logic circuit in the rigid physical architecture. In this paper, we propose a novel 3-bit arbitrary magneto-logic circuit beyond the simple combinational logic or the short sequential one. We design the 3-bit magneto-logic which has the most complexity using MTJ elements and verify its functionality. The simulation results are presented with the HSPICE macro-model of MTJ that we have developed in our previous work. This novel magneto-logic based on MTJ can realize the most complex logic function. What is more, 3-bit arbitrary logic operations can be implemented by changing gate signals of the current drivel circuit.

• Journal of Environmental Health Sciences
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• v.40 no.6
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• pp.492-501
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• 2014

Objectives: The purpose of this study was to assess the validity of self-reported cigarette smoking status and investigate factors associated with the accuracy self-reported and measured urinary cotinine in Korean adults. Methods: We used data from the $1^{st}$ Korean National Environmental Health Survey (2009-2011) among adults aged ${\geq}19$ years (N=6,246). The survey examined self-reported smoking status, and urinary cotinine was regarded as the biomarker of exposure to tobacco smoke. Urinary cotinine was analyzed using a gas chromatography-mass spectrometry (GC/MS) and data analysis was conducted using IBM SPSS version 20.0, which uses the sample weight and calculates variance estimates to adjust for the unequal probability of selection into the survey. Results: We calculated a cut-off point (53.3 ug/L) by using a ROC (Receiver Operating Characteristic) curve. The smoking prevalence was 24.6% based on self-reported data and 28.2% based on urinary cotinine concentrations. When we assessed the agreement between self-reported and urinary cotinine, we found an average agreement of 97.7% among self-reported smokers and 94.5% among self-reported non-smokers. Among self-reported smokers, factors affected the discrepancy were age, household economic status and average number of cigarettes smoked per day. On the other hand, gender, former smoking experience, and exposure to SHS (second hand smoke) were associated with discrepancies among self-reported non-smokers. Conclusion: These results suggest that self-reported data on smoking status provide a valid estimate of actual smoking status. In future research, we will conduct a continuous monitoring study for reliability verification of the data to reduce potential interpretation errors.