• Journal of Environmental Policy
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• v.13 no.1
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• pp.69-93
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• 2014

The aim of this research was to develop a climate change vulnerability index at the district level (Si, Gun, Gu) with respect to the health care sector in Korea. The climate change vulnerability index was esimated based on the four major causes of climate-related illnesses : vector, flood, heat waves, and air pollution/allergies. The vulnerability assessment framework consists of six layers, all of which are based on the IPCC vulnerability concepts (exposure, sensitivity, and adaptive capacity) and the pathway of direct and indirect impacts of climate change modulators on health. We collected proxy variables based on the conceptual framework of climate change vulnerability. Data were standardized using the min-max normalization method. We applied the analytic hierarchy process (AHP) weight and aggregated the variables using the non-compensatory multi-criteria approach. To verify the index, sensitivity analysis was conducted by using another aggregation method (geometric transformation method, which was applied to the index of multiple deprivation in the UK) and weight, calculated by the Budget Allocation method. The results showed that it would be possible to identify the vulnerable areas by applying the developed climate change vulnerability assessment index. The climate change vulnerability index could then be used as a valuable tool in setting climate change adaptation policies in the health care sector.

• Korean Journal of Construction Engineering and Management
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• v.10 no.4
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• pp.26-37
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• 2009

Ministry of Land, Transportation and Marine Affairs(MLTM) has implemented Construction CALS project for improving productivity of construction industry and for making construction project management efficient by responding to informatization and knowledge base society in 21st century. CALS has beeb applied successfully to projects form MLTM, however, the outcomes of Construction CALS hasn't been recognized. In addition, there is no way to find how high the level of Construction CALS is when it is compared with other SOC informatization projects. This study found out the informatiziation level of Construction CALS by using the evaluation index proposed in the former study, and by comparing with other sectors. The evaluation on the level was implemented in the three parts such as informatization infrastructure(network, hardware, standardization, data, informatization, informatization security), informatization utilization(information usage, IT performance), and informatization support(informatization goal, organization of informatization, informatization investment, informatization education), and then, this evaluation was compared with "Assessment for level of industry information system", "Assessment for level of small and midium sized industry information system", and "IICI(Informatizaion Index for the Construction Industry)". With the result from the comparison, this study produced superior factors and inferior factors for each sector. These results are expected to be useful for prioritizing budget allocation by finding out the informatization level of Construction CALS.

• Korean Journal of Construction Engineering and Management
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• v.11 no.1
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• pp.59-69
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• 2010

Although international construction market gradually takes a important position among the export industries, the previous studies about international construction entry strategy have just focussed on trend investigation or suggestion for revitalization. Moreover, in order to prepare the market uncertainty such as world financial crisis and to plan the long term strategy, specific strategy studies based on corporate level are required. Therefore, this study estimates the nine strategic index and four financial index of 31 companies that performed 1920 international projects from 1993 to 2007 and evaluate the performance as three periods by multi-regression analysis. Also, this study analyze dynamic correlation between these index and the performance considering times. this study verifies that market diversification, product diversification, localization and decrease of debt to asset ratio make a good effect on the international order as long term strategy and shows that collaborated entry with domestic corporations, alliance entry with host country's company, alliance entry with third country's company, portion of labor cost and portion of management expense differently make a influence on the performance as times. these results will be helpful for the construction companies to plan the international entry strategy reasonably and specifically.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1581-1589
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• 2013

The aim of this study is to suggest a methodology for calculating the peak-hour ratio of passengers at urban railway stations by reflecting the characteristics of passenger demand patterns and the land use inventory of stations. To achieve this, urban railway stations in Seoul are divided into three groups by using factor analysis and cluster analysis. For each station group, we calculate five and four variables related to the passenger demand patterns and the land use inventory of stations, respectively, as well as the peak-hour ratios of passengers. Among these nine variables, average daily passengers and the location quotient (LQ) index for business services are selected as the classification criteria for station groups based on statistical tests. Using the two variables, a group allocation process is suggested to estimate the peak-hour ratio of passengers for a newly-constructed station. Evaluation results based on thirteen stations show that the proposed methodology produces lower errors than the currently-used guideline does. The results of this study contribute to establishing efficiently construction and operation plans for newly-constructed stations.

• Sleep Medicine and Psychophysiology
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• v.5 no.2
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• pp.119-133
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• 1998

Attentional processes facilitate cognitive and behavioral performance in several ways. Attention serves to reduce the amount of information to receive. Attention enables humans to direct themselves to appropriate aspects of external environmental events and internal operations. Attention facilitates the selection of salient information and the allocation of cognitive processing appropriate to that information. Attention is not a unitary process that can be localized to a single neuroanatomical region. Before the cortical registration of sensory information, activation of important subcortical structures occurs, which is called as an orienting response. Once sensory information reaches the sensory cortex, a large number of perceptual processes occur, which provide various levels of perceptual resolution of the critical features of the stimuli. After this preattentional processing, information is integrated within higher cortical(heteromodal) systems in inferior parietal and temporal lobes. At this stage, the processing characteristics can be modified, and the biases of the system have a direct impact on attentional selection. Information flow has been traced through sensory analysis to a processing stage that enables the new information to be focused and modified in relation to preexisting biases. The limbic and paralimbic system play significant roles in modulating attentional response. It is labeled with affective salience and is integrated according to ongoing pressures from the motivational drive system of the hypothalamus. The salience of information greatly influences the allocation of attention. The frontal lobe operate response selection system with a reciprocal interaction with both the attention system of the parietal lobe and the limbic system. In this attentional process, the search with the spatial field is organized and a sequence of attentional responses is generated. Affective, motivational and appectitive impulses from limbic system and hypothalamus trigger response intention, preparation, planning, initiation and control of frontal lobe on this process. The reticular system, which produces ascending activation, catalyzes the overall system and increases attentional capacity. Also additional energetic pressures are created by the hypothalamus. As psychophysiological measurement, skin conductance, pupil diameter, muscle tension, heart rate, alpha wave of EEG can be used. Event related potentials also provide physiological evidence of attention during information process. NI component appears to be an electrophysiological index of selective attention. P3 response is developed during the attention related to stimulus discrimination, evaluation and response.

• The Journal of the Korea Contents Association
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• v.22 no.10
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• pp.691-702
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• 2022

This study verifies the diversification effect when non-financial asset such as fractional music royalties investment which is recently get interest from masses, is included in traditional global asset allocation portfolio. From Jan 2019 when Music Royalties index is announced to Jun 2022, compared traditional global asset allocation portfolio and the portfolio included with music royalties. To eliminate the enhancement effect from portfolio strategy itself rather than including non-financial asset, used the four basic portfolio strategy such as buy & hold, constant rebalanced, mean variance, risk parity. As a result, all the portfolios included with music royalties shows less risk with higher returns. This means the sharpe ratio has enhanced and that results the portfolio diversification effect is placed. The empirical analysis of the study found academic significance in that the portfolio included with music royalties investment has diversification effect, and show the possibilities the not only on the music royalties, other non-financial asset can be shown the portfolio diversification effect.

• Journal of Intelligence and Information Systems
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• v.25 no.2
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• pp.39-55
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• 2019

Recently banks and large financial institutions have introduced lots of Robo-Advisor products. Robo-Advisor is a Robot to produce the optimal asset allocation portfolio for investors by using the financial engineering algorithms without any human intervention. Since the first introduction in Wall Street in 2008, the market size has grown to 60 billion dollars and is expected to expand to 2,000 billion dollars by 2020. Since Robo-Advisor algorithms suggest asset allocation output to investors, mathematical or statistical asset allocation strategies are applied. Mean variance optimization model developed by Markowitz is the typical asset allocation model. The model is a simple but quite intuitive portfolio strategy. For example, assets are allocated in order to minimize the risk on the portfolio while maximizing the expected return on the portfolio using optimization techniques. Despite its theoretical background, both academics and practitioners find that the standard mean variance optimization portfolio is very sensitive to the expected returns calculated by past price data. Corner solutions are often found to be allocated only to a few assets. The Black-Litterman Optimization model overcomes these problems by choosing a neutral Capital Asset Pricing Model equilibrium point. Implied equilibrium returns of each asset are derived from equilibrium market portfolio through reverse optimization. The Black-Litterman model uses a Bayesian approach to combine the subjective views on the price forecast of one or more assets with implied equilibrium returns, resulting a new estimates of risk and expected returns. These new estimates can produce optimal portfolio by the well-known Markowitz mean-variance optimization algorithm. If the investor does not have any views on his asset classes, the Black-Litterman optimization model produce the same portfolio as the market portfolio. What if the subjective views are incorrect? A survey on reports of stocks performance recommended by securities analysts show very poor results. Therefore the incorrect views combined with implied equilibrium returns may produce very poor portfolio output to the Black-Litterman model users. This paper suggests an objective investor views model based on Support Vector Machines(SVM), which have showed good performance results in stock price forecasting. SVM is a discriminative classifier defined by a separating hyper plane. The linear, radial basis and polynomial kernel functions are used to learn the hyper planes. Input variables for the SVM are returns, standard deviations, Stochastics %K and price parity degree for each asset class. SVM output returns expected stock price movements and their probabilities, which are used as input variables in the intelligent views model. The stock price movements are categorized by three phases; down, neutral and up. The expected stock returns make P matrix and their probability results are used in Q matrix. Implied equilibrium returns vector is combined with the intelligent views matrix, resulting the Black-Litterman optimal portfolio. For comparisons, Markowitz mean-variance optimization model and risk parity model are used. The value weighted market portfolio and equal weighted market portfolio are used as benchmark indexes. We collect the 8 KOSPI 200 sector indexes from January 2008 to December 2018 including 132 monthly index values. Training period is from 2008 to 2015 and testing period is from 2016 to 2018. Our suggested intelligent view model combined with implied equilibrium returns produced the optimal Black-Litterman portfolio. The out of sample period portfolio showed better performance compared with the well-known Markowitz mean-variance optimization portfolio, risk parity portfolio and market portfolio. The total return from 3 year-period Black-Litterman portfolio records 6.4%, which is the highest value. The maximum draw down is -20.8%, which is also the lowest value. Sharpe Ratio shows the highest value, 0.17. It measures the return to risk ratio. Overall, our suggested view model shows the possibility of replacing subjective analysts's views with objective view model for practitioners to apply the Robo-Advisor asset allocation algorithms in the real trading fields.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.12
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• pp.529-538
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• 2002

Conventional method to reduce the handoff call blocking probability(PBH) in mobile communication system is to reserve a predetermined number of channels only for handoff calls. To determine the number of reserved channels, an optimization problem, which is generally computationally heavily involved, must be solved. In this Paper, we propose a call admission control (CAC) scheme that can be used to reduce the PBH without reserving channels in advance. For this, we define a new measure, gain, which depends on the state of the system upon the arrival of a new call. The proposed CAC decision rule relies on the gain computed when a new call arrives. SRN, an extended stochastic Petri nets, provides compact modeling facilities for system analysis can be calculated performance index by appropriate reward to the model. In this Paper, we develop SRN models which can perform the CAC with gain. The SRN models are 2 level hierarchical models. The upper layer models are the structure state model representing the CAC and channel allocation methods considering QoS with multimedia traffic The lower layer model Is to compute the gain under the state of the upper layer models.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.6
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• pp.1463-1479
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• 2013

In this paper, we propose an unequal protection physical coding sub-layer (PCS) forward error correction (FEC) scheme for efficient and high-quality transmission of video data over optical access networks. Through identifying and resolving the unequal importance of different video frames and passing this importance information from MAC-layer to PCS, FEC scheme of PCS can be adaptive to application-layer data. Meanwhile, we jointly consider the different channel situations of optical network unit (ONU) and improve the efficiency of FEC redundancy by channel adaptation. We develop a theoretical algorithm and a hardware method to achieve efficient FEC assignment for the proposed unequal protection scheme. The theoretical FEC assignment algorithm is to obtain the optimal FEC redundancy allocation vector that results in the optimum performance index, namely frame error rate, based on the identified differential importance and channel situations. The hardware method aims at providing a realistic technical path with negligible hardware cost increment compared with the traditional FEC scheme. From the simulation results, the proposed Channel and Application-layer data Adaptation Unequal Protection (CAAUP) FEC scheme along with the FEC ratio assignment algorithm and the hardware method illustrates the ability of efficient and high-quality transmission of video data against the random errors in the channel of optical access networks.

• The Journal of Internal Korean Medicine
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• v.36 no.3
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• pp.308-322
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• 2015

Objectives: Whether there exists a distinct pathogenesis in subgroups of functional dyspepsia (FD), the classification of epigastric pain syndrome (EPS), and postprandial distress syndrome (PDS) remains controversial. We aimed to investigate the number of fungiform papillae (FP) in the subgroups of FD and its correlation with the severity of dyspepsia symptoms and spleen qi deficiency. Methods: Patients with FD were enrolled from August to November 2014. All patients were evaluated using a questionnaire and divided into 2 groups according to the Rome III criteria for FD. The severity of dyspepsia symptoms and spleen qi deficiency were separately assessed by Nepean Dyspepsia Index-Korean (NDI-K) version and Spleen qi deficiency questionnaire (SQDQ). The number of FP was measured on the anterior part of tongue, within an area of 9 mm ², using a digital cam Results: The NDI-K score, SQDQ score, and number of FP in the EPS group were significantly greater than those in the PDS group. Also, the EPS group had more patients diagnosed with spleen qi deficiency. The number of FP showed a significant positive correlation with epigastric pain and burning. Furthermore, the number of FP was significantly associated with the score of some items in NDI-K and SQDQ, even though not with the total score. Conclusions: Thus, measurement of the number of FP could be a new evaluation indicator for allocation into FD subtypes and to investigate the severity of dyspepsia symptoms and spleen Qi deficiency reflecting visceral hypersensitivity.