• Journal of Information Display
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• v.12 no.3
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• pp.145-152
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• 2011

Since the discovery of fullerenes as a class of nanostructure compounds, many potential applications have been suggested for their unusual structures and properties. The isolated pentagon rule (IPR) states that all pentagonal carbon rings are isolated in the most stable fullerene. Fullerenes $C_n$ are a class of spherical carbon allotrope group with unique properties. Electron transfer between fullerenes and other molecules is thought to involve the transfer of electrons between the molecules surrounding the fullerene cage. One class of electron transfer molecules is the methanofullerene derivatives ([6,6]-phenyl $C_{61}$-butyric acid methyl ester (PCBM), 4-(2-ethylhexyloxy)-[6,6]-phenyl $C_{61}$-butyric acid methyl ester (p-EHO-PCBM), and 4-(2-ethylhexyloxy)-[6,6]-phenyl $C_{61}$-butyric acid (p-EHO-PCBA), 10-12). It has been determined that $C_{60}$ does not obey IPR. Supramolecular complexes 1-9 and 10-12 are shown to possess a previously unreported host.guest interaction for electron transfer processes. The unsaturated, cis-geometry, thiocrown ethers, (1-9) (described as [X-UT-Y], where X and Y indicate the numbers of carbon and sulfur atoms, respectively), are a group of crown ethers that display interesting physiochemical properties in the light of their conformational restriction compared with a corresponding saturated system, as well as the sizes of their cavities. Topological indices have been successfully used to construct mathematical methods that relate structural data to various chemical and physical properties. To establish a good relationship between the structures of 1-9 with 10-12, a new index is introduced, ${\mu}_{cs}$. This index is the ratio of the sum of the number of carbon atoms ($n_c$) and the number of sulfur atoms ($n_s$) to the product of these two numbers for 1-9. In this study, the relationships between this index and oxidation potential ($^{ox}E_1$) of 1-9, as well as the first to third free energies of electron transfer (${\Delta}G_{et(n)}$, for n = 1-3, which is given by the Rehm-Weller equation) between 1-9 and PCBM, p-EHO-PCBM, and p-EHO-PCBA (10-12) as [X-UT-Y]@R(where R is the adduct PCBM, p-EHO-PCBM, and p-EHO-PCBA group) (13-15) supramolecular complexes are presented and investigated.

• Environmental Analysis Health and Toxicology
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• v.20 no.2 s.49
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• pp.109-121
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• 2005

A chemical ranking and scoring (CRS-Korea) system was developed and proposed to use as the first step to prioritize the toxic chemicals for the purpose of monitoring and detailed risk assessment that might follow as necessary. The CRS-Korea system takes a basic concept of risk assessment (both human health risk and ecological risk) in that risk score is determined by the product of toxicity score and exposure score. Included in the toxicity category are acute toxicity, chronic/sub -chronic toxicity, carcinogenicity, and other toxicity. The exposure category consists of quantity released to the environment, bioconcentration, and persistence. A consistent scheme and a comprehensive chemical data base are offered in the CRS-Korea system to calculate a score for the each component in the two categories by using specific physicochemical, fate, and toxic properties and the quantity of the chemical used. The toxicity score is obtained by adding up all the individual scores for the components in the toxicity category. The exposure score is determined by multiplication of the score of the quantity released with the sum of persistent score and bioconcentration score. Equal weight is given to the toxicity score and the exposure score. As the CRS-Korea system was applied to identify 50 national priority chemicals, it was found that significant data gap exists on toxicity and fate properties and that the uncertainty associated with estimating the quantify released to the environment is notably high. The proposed CRS system is only a screening tool in the first step toward the priority setting and should be used with expert judgement and other considerations necessary.

• Journal of the Korean Society for information Management
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• v.34 no.1
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• pp.177-195
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• 2017

This study attempts to infer research fronts using factor graph model based on heterogeneous features. The model suggested by this study infers research fronts having documents with the potential to be cited multiple times in the future. To this end, the documents are represented by bibliographic, network, and content features. Bibliographic features contain bibliographic information such as the number of authors, the number of institutions to which the authors belong, proceedings, the number of keywords the authors provide, funds, the number of references, the number of pages, and the journal impact factor. Network features include degree centrality, betweenness, and closeness among the document network. Content features include keywords from the title and abstract using keyphrase extraction techniques. The model learns these features of a publication and infers whether the document would be an RF using sum-product algorithm and junction tree algorithm on a factor graph. We experimentally demonstrate that when predicting RFs, the FG predicted more densely connected documents than those predicted by RFs constructed using a traditional bibliometric approach. Our results also indicate that FG-predicted documents exhibit stronger degrees of centrality and betweenness among RFs.

• Journal of the Korean earth science society
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• v.32 no.3
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• pp.249-264
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• 2011

A multi-Gaussian kriging approach extended to space-time domain is presented for uncertainty modeling as well as time-series mapping of environmental variables. Within a multi-Gaussian framework, normal score transformed environmental variables are first decomposed into deterministic trend and stochastic residual components. After local temporal trend models are constructed, the parameters of the models are estimated and interpolated in space. Space-time correlation structures of stationary residual components are quantified using a product-sum space-time variogram model. The ccdf is modeled at all grid locations using this space-time variogram model and space-time kriging. Finally, e-type estimates and conditional variances are computed from the ccdf models for spatial mapping and uncertainty analysis, respectively. The proposed approach is illustrated through a case of time-series Particulate Matter 10 ($PM_{10}$) concentration mapping in Incheon Metropolitan city using monthly $PM_{10}$ concentrations at 13 stations for 3 years. It is shown that the proposed approach would generate reliable time-series $PM_{10}$ concentration maps with less mean bias and better prediction capability, compared to conventional spatial-only ordinary kriging. It is also demonstrated that the conditional variances and the probability exceeding a certain thresholding value would be useful information sources for interpretation.

• Culinary science and hospitality research
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• v.10 no.3
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• pp.97-118
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• 2004

As the economy grows rapidly and the national income level increases, the service industry has become more important and its size gets larger. Especially, the food industry undertakes a continuing growth of consumer expenditures through no nationalization of food, consumers varying patterns of eating out, and individualization. However, it includes many problems with improving service quality towards customers owing to the absence of systems and philosophy to realize customer satisfaction management Therefore, this study conducted a study with Korean traditional restaurant customers to measure their perceived service quality, to verify what factors most influence consumer satisfaction, and to suggest ways to meet the costumer needs by integrating the study results and developing high service quality. To sum up the results of this study, Korean traditional restaurant visitors evaluated three dimensions of service quality overall favorably. Interestingly, background music received a lower level of satisfaction. This implies that the Korean traditional restaurant managers do not do a fine performance in managing music as an ambient element to evoke the atmosphere of the restaurant. Customers showed a lower satisfaction with menu price among the factors measuring product quality. As a result of this study, several suggestions have been made as follows: First, it is necessary for the Korean traditional restaurants to provide systematic employee training to instigate a service culture of customer focus. Secondly, it is important to develop traditional foods using ingredients produced in the region based on a literature review of food in Gyeongju, Silla. Thirdly, it is an urgent task to develop regional menus to revitalize the restaurant business. Fourthly, it is important to provide safety food through systematic sanitary administration. Lastly, it is necessary to limit the number of menu items and attempt specialization of them. Such an attempt with specialized menu items will help their food taste and quality improve and thereby reduce inventory burdens. However, this study has a few limitations. Since this study conducted a survey of the restaurants which provides only Korean traditional food in Gyeongju, not all the restaurants in it, there is a limitation in measuring customer satisfaction with service quality. Therefore, the study results cannot be generalized to all the restaurants in Gyeongju and the nation. Finally, this study suggests that studies on the relationships between customer satisfaction and menu price and customer value system or further customer satisfaction studies with Korean traditional restaurants should be continued.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1999.04a
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• pp.426-426
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• 1999

;There are many sources of uncertainty in a typical production and inventory system. There is uncertainty as to how many items customers will demand during the next day, week, month, or year. There is uncertainty about delivery times of the product. Uncertainty exacts a toll from management in a variety of ways. A spurt in a demand or a delay in production may lead to stockouts, with the potential for lost revenue and customer dissatisfaction. Firms typically hold inventory to provide protection against uncertainty. A cushion of inventory on hand allows management to face unexpected demands or delays in delivery with a reduced chance of incurring a stockout. The proposed strategies are used for the design of a probabilistic inventory system. In the traditional approach to the design of an inventory system, the goal is to find the best setting of various inventory control policy parameters such as the re-order level, review period, order quantity, etc. which would minimize the total inventory cost. The goals of the analysis need to be defined, so that robustness becomes an important design criterion. Moreover, one has to conceptualize and identify appropriate noise variables. There are two main goals for the inventory policy design. One is to minimize the average inventory cost and the stockouts. The other is to the variability for the average inventory cost and the stockouts The total average inventory cost is the sum of three components: the ordering cost, the holding cost, and the shortage costs. The shortage costs include the cost of the lost sales, cost of loss of goodwill, cost of customer dissatisfaction, etc. The noise factors for this design problem are identified to be: the mean demand rate and the mean lead time. Both the demand and the lead time are assumed to be normal random variables. Thus robustness for this inventory system is interpreted as insensitivity of the average inventory cost and the stockout to uncontrollable fluctuations in the mean demand rate and mean lead time. To make this inventory system for robustness, the concept of utility theory will be used. Utility theory is an analytical method for making a decision concerning an action to take, given a set of multiple criteria upon which the decision is to be based. Utility theory is appropriate for design having different scale such as demand rate and lead time since utility theory represents different scale across decision making attributes with zero to one ranks, higher preference modeled with a higher rank. Using utility theory, three design strategies, such as distance strategy, response strategy, and priority-based strategy. for the robust inventory system will be developed.loped.

• Journal of the Korean Magnetic Resonance Society
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• v.5 no.2
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• pp.99-109
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• 2001

Authors investigated neuronal changes of local cellular metabolism in the cerebral lesions of Parkinsonian symptomatic side between before and after stereotactic neurosurgery by follow-up 1H magnetic resonance spectroscopy (MRS). Patients with Parkinson's disease (PD) (n = 15) and age-matched normal controls (n = 15) underwen MRS examinations using a stimulated echo acquisition mode (STEAM) pulse sequence that provided 2${\times}$2${\times}$2 ㎤ (8ml) volume of interest in the regions of substantia nigra, thalamus, and lentiform nucleus. Spectral parameters were 20 ms TE, 2000 ms TR, 128 averages,2500 Hz spectral width, and 2048 data points. Raw data were processed by the SAGE data analysis package (GE Medical Systems). Peak areas of N-acetylaspartate (NAA), creatine (Cr), choline-containing compounds (Cho), inositols (Ins), and the sum (Glx) of glutamate and GABA were calculated by means of fitting the spectrum to a summation of Lorentzian curves using Marquardt algorithm. After blindly processed, we evaluated neuronal alterations of observable metabolite ratios between before and after stereotactic neurosurgery using Pearson product-moment analysis (SPSS, Ver. 6.0). A significant reduction of NAA/Cho ratio was observed in the cerebral lesion in substantia nigra of PD patient related to the symptomatic side after neurosurgery (P : 0.03). In thalamus, NAA/Cho ratio was also significantly decreased in the cerebral lesion including the electrode-surgical region (P : 0.03). A significant reduction of NAA/Cho ratio in lentiform nucleus was not oberved, but tended toward significant reduction after neurosurgery (P = 0.08). In particular, remarkable lactate signal was noted from the surgical thalamic lesions of 6 among 8 patients and internal segments of globus pallidus of 6 among 7 patients, respectively. Significant metabolic alterations of NAA/Cho ratio might reflect functional changes of neuropathological processes in the lesion of substantia nigra, thalamus, and lentiform nucleus, and could be a valuable finding fur evaluation of Parkinson's disease after neurosurgery. Increase of lactate signals, being remarkable in surgical lesions, could be consistent with a common consequence of neurosurgical necrosis. Thus, IH MRS could be a useful modality to evaluate the diagnostic and prognostic implications fur Parkinsons disease after functional neurosurgery.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.4
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• pp.562-566
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• 2005

This study was conducted to investigate the developmental relationship between fatty acid composition in different lipid fractions and stearoyl-CoA desaturase (SCD) gene expression in steer muscles during growth. Twenty Hanwoo steers were used at 6, 12, 18, 24 and 30 months of age. Fatty acid composition and SCD mRNA level were analyzed. In the total lipid fraction, developmental profiles of C18:1, as the product of SCD enzyme, and SCD mRNA level were significantly increased between 6 months and 12 months of age. During this period, the percentage of C18:1 increased from 31.9% to 49.5% in the total lipid. The increased C18:1 level was maintained until 30 months of age within the range of 44.8- 49.9%. In contrast, the C18:0 composition decreased with age and this decrease was compensated by the increase of the C18:1. However, the sum of C18:0 and C18:1 was changed before and after 12-month old by a 20% increase. Unlike the C18 fatty acids, the C16 fatty acids such as C16:0 and C16:1 did not show a consistent change with age in steers' muscle. On the other hand, C18:2 proportion as a major polyunsaturated fatty acid in muscle was significantly reduced from 21.1% at 6 months of age to 4.4% at 12-months old and then this reduced level was maintained until 30 months within the range of 7.4-11.4%. As in the C18:1 composition during early stages, a 2-fold significant increase was observed in the $\Delta^9$-desaturase index of C18 fatty acid as a measure of SCD activity, but not in that of C16 fatty acid. Also, the steady-state level of SCD mRNA reached a peak at 12 months of age. Thus, the positive relationship between the C18:1 composition and the $\Delta^9$-desaturase (SCD enzyme) index of C18 fatty acid or SCD mRNA level was demonstrated during growth, but the negative relationship between the C18:2 composition and the above three indices was demonstrated at the same time, indicating that the sharp induction of SCD mRNA may be closely related to the dramatic reduction of C18:2, which is known as a suppressor of SCD gene expression during growth.

• Cartoon and Animation Studies
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• s.45
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• pp.417-434
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• 2016

The wall painting of Altamira cave "eight-legged wild boar" is often presented as a typical example of long-held desire of humanity for expressing movement. However, the eight legs are the product of so-called "double layer", of two paintings painted in different periods. Nonetheless, the explanation of Altamira cave paintings linking with the origin of animation is constantly reproduced without any particular doubt, verification or citation of sources. The fact of associating eight legs with movement is irrelevant to visual perception transcending time. This should be considered a movement expression code invented in a particular period of time. Sequential photography tried in the late 19th century, in particular, chronography of $\acute{E}tienne$-Jules Marey plays a crucial role in this. Marey's photography of which a series of sequence movements are overlapped in one frame and printed was reflected in painting works of artists including Duchamp and Balla in the early 20th century and formed as movement expression code. Animation manuals started to emerge from that period of time introduced the images of Marey's chronophotography as a way of analyzing and embodying the movement. In sum, the act of considering Altamira cave paintings of eight-legged wild boar as an expression of movement is an error intending to look at the past through today's visual code.

• Journal of the Korean association of regional geographers
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• v.17 no.4
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• pp.432-442
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• 2011

Climatic variables such as temperature and precipitation tend to vary both in space and in time simultaneously. Thus, it is necessary to include space-time autocorrelation into conventional spatial interpolation methods for reliable time-series mapping. This paper introduces and applies space-time variogram modeling and space-time kriging to generate time-series temperature maps using hourly Automatic Weather System(AWS) temperature observation data for a one-month period. First, temperature observation data are decomposed into deterministic trend and stochastic residual components. For trend component modeling, elevation data which have reasonable correlation with temperature are used as secondary information to generate trend component with topographic effects. Then, space-time variograms of residual components are estimated and modelled by using a product-sum space-time variogram model to account for not only autocorrelation both in space and in time, but also their interactions. From a case study, space-time kriging outperforms both conventional space only ordinary kriging and regression-kriging, which indicates the importance of using space-time autocorrelation information as well as elevation data. It is expected that space-time kriging would be a useful tool when a space-poor but time-rich dataset is analyzed.