• Atmosphere
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• v.21 no.2
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• pp.131-142
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• 2011

Spectral solar irradiances were observed using a visible and UV Multi-Filter Rotating Shadowband Radiometer on the rooftop of the Science Building at Yonsei University, Seoul ($37.57^{\circ}N$, $126.98^{\circ}E$, 86 m) during one year period in 2006. 1-min measurements of global(total) and diffuse solar irradiances over the solar zenith angle (SZA) ranges from $20^{\circ}$ to $70^{\circ}$ were used to examine the effects of clouds and total optical depth (TOD) on enhancing four solar irradiance components (broadband 395-955 nm, UV channel 304.5 nm, visible channel 495.2 nm, and infrared channel 869.2 nm) together with the sky camera images for the assessment of cloud conditions at the time of each measurement. The obtained clear-sky irradiance measurements were used for empirical model of clear-sky irradiance with the cosine of the solar zenith angle (SZA) as an independent variable. These developed models produce continuous estimates of global and diffuse solar irradiances for clear sky. Then, the clear-sky irradiances are used to estimate the effects of clouds and TOD on the enhancement of surface solar irradiance as a difference between the measured and the estimated clear-sky values. It was found that the enhancements occur at TODs less than 1.0 (i.e. transmissivity greater than 37%) when solar disk was not obscured or obscured by optically thin clouds. Although the TOD is less than 1.0, the probability of the occurrence for the enhancements shows 50~65% depending on four different solar radiation components with the low UV irradiance. The cumulus types such as stratoculmus and altoculumus were found to produce localized enhancement of broadband global solar irradiance of up to 36.0% at TOD of 0.43 under overcast skies (cloud cover 90%) when direct solar beam was unobstructed through the broken clouds. However, those same type clouds were found to attenuate up to 80% of the incoming global solar irradiance at TOD of about 7.0. The maximum global UV enhancement was only 3.8% which is much lower than those of other three solar components because of the light scattering efficiency of cloud drops. It was shown that the most of the enhancements occurred under cloud cover from 40 to 90%. The broadband global enhancement greater than 20% occurred for SZAs ranging from 28 to $62^{\circ}$. The broadband diffuse irradiance has been increased up to 467.8% (TOD 0.34) by clouds. In the case of channel 869.0 nm, the maximum diffuse enhancement was 609.5%. Thus, it is required to measure irradiance for various cloud conditions in order to obtain climatological values, to trace the differences among cloud types, and to eventually estimate the influence on solar irradiance by cloud characteristics.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.135-147
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• 2008

One of the efforts both to prevent urban sprawling development patterns and to promote use of public transportation is known as Transit-Oriented Development (TOD), including such planning elements as the density and diversity of land use and pedestrian-friendly urban design around a transit center. The aim of this study is thus to conduct impact analyses of TOD planning elements on transit ridership in the Seoul rail station areas. First, the authors investigate and draw out various actual elements of TOD planning by using GIS-based data and Smart Card data. Then the authors analyze impacts of TOD planning elements on transit ridership for the Seoul rail station areas. After condensing 34 variables presumably influencing transit ridership into seven factors by using factor analyses, the study utilizes multiple regression modeling methods to identify their impacts on transit ridership. The analysis results demonstrate that transit ridership tends to increase more in rail station areas where there is a non-residential high density, mixed use of land and narrow and small-size road network patterns. The implementation of TODs should be a useful method in inducing a Transit-Oriented City through redevelopment and new development.

• Journal of Microbiology
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• v.44 no.6
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• pp.591-599
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• 2006

To address the diversity of cyclodextrin-producing P. graminis strains isolated from wheat roots and rhizospheres of maize and sorghum sown in Australia, Brazil, and France, restriction fragment length polymorphism analysis of part of genes encoding RNA polymerase (rpoB-RFLP) and DNA gyrase subunit B (gyrB-RFLP) was used to produce genetic fingerprints. A phylogenetic tree based on rpoB gene sequences was also constructed. The isolates originated from Brazil could be separated from those from Australia and France, when data from the rpoB-based phylogenetic tree or gyrB-RFLP were considered. These analyses also allowed the separation of all P. graminis strains studied here into four clusters; one group formed by the strains GJK201 and $RSA19^T$, second group formed by the strains MC22.02 and MC04.21, third group formed by the strains TOD61, TOD 221, TOD302, and TOD111, and forth group formed by all strains isolated from plants sown in Cerrado soil, Brazil. As this last group was formed by strains isolated from sorghum and maize sown in the same soil (Cerrado) in Brazil, our results suggest that the diversity of these P. graminis strains is more affected by the soil type than the plant from where they have been isolated.

• Journal of Industrial Convergence
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• v.17 no.4
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• pp.45-51
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• 2019

In this study, climate change considerations are an important measure to create a resilient city that conforms to the principle of sustainable development that balances the economic, social and environmental harmony of a country or city and can preserve its size, function and characteristics to the maximum extent possible. In this regard, the public transportation system being built and operated in Dublin City, Ireland, illustrates the city's system through green traffic. Therefore, based on the urban-based conditions equipped by Dublin, Ireland, in that Dublin is realizing preemptive mass-traffic-oriented urban development (TOD) considering climate change, the purpose of the study was to classify the methods of research as internal (strong and weak) and external (opportunity and threat) factors through SWOT analysis and to present mass-oriented urban development strategies and policy implications.

• The Transactions of the Korea Information Processing Society
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• v.5 no.3
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• pp.662-670
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• 1998

In order to overcome the problems with first generation expert systems at the symbol level, recently various knowledge level development techniques of second generation expert systems have been proposed. But, these techniques are conceptual modelling techniques. This paper modifies and complements these conceptual modelling techniques and proposes a Task Object Modelling (TOM) technique as a practical knowledge level expert system development technique. This paper defines a Task Object(TO) as a knowledge unit consisted of a goal, execution conditions, behaviour knowledge, and so on. And, we define a Task Object Diagram(TOD) to depict structual, dynamic, and functional aspects of TO easily. We also define Inference Types as basic units to describe behaviour knowledge of TOs. In order to utilize the proposed TOM technique as not a simple conceptual modelling technique but a practical second generalion expert system development technique, we implement a TOD editor, a TO editor, and TO processing algorithm based on the state of TOs. Also we implement a Inference Types Library, in which each inference type is corresponded to an IRE(Jntelligent Rules Element) method, to transform the defined inference types into IRE methods automatically.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.4
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• pp.1-14
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• 2023

As markets and industries continue to evolve rapidly, technology opportunity discovery (TOD) has become critical to a firm's survival. From a common consensus that TOD based on a firm's capabilities is a valuable method for small and medium-sized enterprises (SMEs) and reduces the risk of failure in technology development, studies for TOD based on a firm's capabilities have been actively conducted. However, previous studies mainly focused on a firm's technological capabilities and rarely on business capabilities. Since discovered technologies can create market value when utilized in a firm's business, a firm's current business capabilities should be considered in discovering technology opportunities. In this context, this study proposes a TOD method that considers both a firm's business and technological capabilities. To this end, this study uses patent data, which represents the firm's technological capabilities, and trademark data, which represents the firm's business capabilities. The proposed method comprises four steps: 1) Constructing firm technology and business capability matrices using patent classification codes and trademark similarity group codes; 2) Transforming the capability matrices to preference matrices using the fuzzy function; 3) Identifying a target firm's candidate technology opportunities using the collaborative filtering algorithm; 4) Recommending technology opportunities using a portfolio map constructed based on technology similarity and applicability indices. A case study is conducted on a security firm to determine the validity of the proposed method. The proposed method can assist SMEs that face resource constraints in identifying technology opportunities. Further, it can be used by firms that do not possess patents since the proposed method uncovers technology opportunities based on business capabilities.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.6
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• pp.66-76
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• 2023

The government recently implemented policies to improve transportation for the disabled passengers. On the other hand, metropolitan public transport still lacks adequate services for these individuals. Many new cities lack urban rail lines and focus on high-floor buses for expansion. Wheelchair users can only access to double-decker low-floor seat express buses for intercity travel. This study examined the necessity and rationale for introducing low-floor seat buses by estimating the user's willingness to pay through a contingent valuation method. Two methods for eliciting the willingness to pay were adopted: open-ended and dichotomous choice questions. The binomial logit model was used to estimate the willingness to pay. The results indicated that the general public is willing to pay an additional 126.7 Korean won, while the disabled passengers are willing to pay an additional 117.5 Korean won. When translated into annual economic benefits, this amounts to approximately 35 billion Korean won.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.6
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• pp.519-528
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• 1993

The biodegradation experiment, the TOD analysis and the element analysis for dispersant, Bunker-C and dispersant/Bunker-C oil mixtures were conducted for the purposes of evaluating the biodegradability of dispersnat/Bunker-C oil mixtures and studying the consumption of dissolved oxygen with relation to biodegradation in the seawater. The results of biodegradation experiment showed the mixtures with $1:10{\sim}5:10$ mix ratios of dispersant to 4mg/l of Bunker-C oil to be $0.34{\sim}2.06mg/l$ of $BOD_5$ and to be $1.05{\sim}5.47mg/l$ of $BOD_{20}$ in natural seawater. The results of TOD analysis showed 1mg of Bunker-C oil to be 3.16mg of TOD. The results of element analysis showed the contents of carbon and hydrogen to be $87.3\%\;and\;11.5\%$ for Bunker-C oil, respectively, but nitrogen element was not detected in Bunker-C oil. The biodegradability of dispersant/Bunker-C oil mixture shown as the ratio of $BOD_5$/TOD was increased from $3\%\;to\;11\%$ as a mix ratio of dispersant to 4mg/l of Bunker-C oil changed from 1:10 to 5:10, and the mixtures were found to belong in the organic matter group of low-biodegradability. The deoxygenation rates($K_1$) and ultimate oxygen demands($L_o$) obtained through the biodegration experiment and Thomas slope method were found to be $0.072{\sim}0.097/day$ and $1.113{\sim}6.746mg/l$ for the mixtures with $1:10{\sim}5:10$ mix ratios of dispersant to 4mg/l of Bunker-C oil, respectively. The ultimate oxygen demand of mixture was increased as a mix ratio of dispersant to Bunker-C oil changed from 1:10 to 10:5. This means that the more dispersants are applied to the sea for Bunker-C oil cleanup, the more decreases the dissolved oxygen level in the seawater.

• Journal of Veterinary Clinics
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• v.38 no.4
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• pp.189-193
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• 2021

An 11-years old spayed female Persian chinchilla cat presented with acute onset of blindness from bilateral retinal detachment and systemic hypertension. On physical examination, the cat was tachycardic (240 beats/min) with a systolic blood pressure of around 250 mmHg. Clinical findings, blood works, urinalysis, thyroid function test, radiography, echocardiogram, and ultrasonography were performed to rule out underlying diseases. Organ injury induced by systemic hypertension including bilateral retinal detachment and left ventricular hypertrophy were confirmed by ultrasound. Based on these results, it was diagnosed as feline idiopathic hypertension with target organ damage (TOD). The cat was treated with a combination therapy using high doses of amlodipine, telmisartan, and atenolol. After the treatment, its hypertension and TOD were improved. This case showed that appropriate therapeutic management can help prevent TOD associated with feline hypertension.

• Journal of Auto-vehicle Safety Association
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• v.14 no.3
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• pp.48-59
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• 2022

A V2X system can be a candidate as a means to increase the stability of autonomous vehicles. In particular, in order to implement a Level 4 or higher autonomous driving system, the application of the V2X system is essential. Wireless communication technologies applicable to the V2X system include WAVE and C-V2X. Currently, the V2X service most used by autonomous driving systems is a service that provides signal phase and timing information and since real-time characteristic is a very important, verification of this service must be done. In this paper, we measured the time delay characteristics for providing signal phase and timing information using WAVE and LTE communication, and proposed a TOD-based signal phase and timing information generation method without using V2X communication system. To analyze the time delay characteristics, RTT (Round Trip Time) was measured as a result of the measurement. Average RTT using WAVE communication was 5.84ms and was 104.15ms with LTE communication. As a result of measuring the error between the signal phase and timing information generated based on TOD and the actual traffic light state, it was measured to be -0.284~3.784sec.