• International Journal of Highway Engineering
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• v.10 no.4
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• pp.65-77
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• 2008

LOS(Level of Service) concept are popularly used in many countries as the MOEs to evaluate the road construction and operation plans. However, MOEs such as travel time and delay only measure quantitative factors describing traffic flow, although qualitative factors such as scenic, comfort and reliable factors are very important for roadway drivers to define the LOS. Therefore, this paper are focusing on verifying the difference between perceived LOS and LOS in KHCM, and proving qualitative factors affecting Drivers' Perceived LOS in Urban Arterial. As a result, following outputs are obtained; (1) verifying the difference between perceived LOS(PLOS) and LOS in KHCM (2) proving that qualitative factors such as scenic and driver behavior factors affects PLOS (3) suggesting that qualitative factors should be considered in MOEs of LOS

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.4910-4918
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• 2013

This study aims to design a Severity-Adjusted LOS(Length of Stay) Model in order to efficiently manage LOS of AMI(Acute Myocardial Infarction) patients. We designed a Severity-Adjusted LOS Model with using data-mining methods(multiple regression analysis, decision trees, and neural network) which covered 6,074 AMI patients who showed the diagnosis of I21 from 2004-2009 Korean National Hospital Discharge in-depth Injury Survey. A decision tree model was chosen for the final model that produced superior results. This study discovered that the execution of CABG, status at discharge(alive or dead), comorbidity index, etc. were major factors affecting a Sevirity-Adjustment of LOS of AMI patients. The difference between real LOS and adjusted LOS resulted from hospital location and bed size. The efficient management of LOS of AMI patients requires that we need to perform various activities after identifying differentiating factors. These factors can be specified by applying each hospital's data into this newly designed Severity-Adjusted LOS Model.

• Journal of Korean Society of Transportation
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• v.33 no.6
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• pp.584-597
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• 2015

A considerable amount of literature has been published on pedestrian LOS. So far, however, there is a limitation that LOS analysis methodologies has concentrated on quantitative variables such as pedestrian flow rate, speed and space. This paper intended to suggest the accessibility variable which can not be considered on previous study. The factor was defined and quantified using public transport attributes in particular. This study was carried out in three phases: 1. defined accessibility employing public mode location and service information. 2. investigated the relationship between accessibility and pedestrian flow rate 3. developed the model to establish the factors affected to pedestrian LOS. The results showed that accessibility, walkway attribute and land use type affected the pedestrian LOS. Especially, accessibility and commercial area ratio had negative relationship with LOS. Futhermore, pedestrian LOS declined when obstacle of bus station located on the walkway. On the contrary, LOS was upgraded when sufficient effective width or residential area was secured. These results can receive considerable critical attentions related to determination of pedestrian LOS or effective walkway width.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.12 s.115
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• pp.1212-1223
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• 2006

Microwave(M/W) bands, though having great demand in wireless services, have been used mostly for long distance communications. As a result, the studies on their mobile radio models have been made less than on VHF/UHF. However, as the mobile communication services with M/W bands have been increasing, the development of a more accurate prediction model of the mobile radio environments has been demanded. The development of a reliable radio prediction model in the mobile radio environments requires the measurement and analysis of the characteristics of the radio waves according to reflection, diffraction and scattering of radio signals in various mobile radio environments. The proposed 8 GHz band radio prediction models have 2 different categories: (1) LOS model and (2) non-LOS model. The LOS model predicts signal strength using the analytic result with measured pathless exponents for the waves direct and reflected by ground and buildings, and the non-LOS model suggests a prediction model of received power by calculating the signal variations after diffraction.

• Journal of Navigation and Port Research
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• v.27 no.4
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• pp.471-478
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• 2003

In the Signalized Intersection, the capacity analysis is conducted with a large amount of input data such as road way, traffic and signal condition. but the level of service(LOS) is determined by delay estimated as a measure of effectiveness (MOE) based on this procedure. However, It is under the circumstances which are not considered for the errors caused by the uncertainty of input data in the field(the turing volumes, lane geometry, signal timing, grade of approach lane, percentage heavy vehicles, peak hour factor and arrival type etc.) as become the bases in the determination of the capacity and LOS. It includes the problem of reliability which is not verified for the capacity and LOS estimated. So, this study is to suggest the minimization of their influences by examining whether the uncertainty of input data such as the traffic volume, percentage of heavy vehicles and roadway geometry on the approach lane in the intersection under the study affects the capacity analysis and LOS determination.

• Natural Product Sciences
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• v.22 no.1
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• pp.60-63
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• 2016

The study is a pioneering effort to determine the mineral, nutritional, and phytochemical composition and phenolic content and to determine the free radical scavenging activity of Gigantochloa levis (Blanco) Merr, a native bamboo species (locally known as "bolo") in the Philippines. Proximate analysis showed that air-dried G. levis leaves contain 15.8% ash, 22.6% crude protein, 1.2% crude fat, 29.3% crude fiber, and 19.7% total sugar. Phytochemical tests indicated the presence of diterpenes, triterpenes, saponins, phenols, tannins, and flavonoids in both the ethanolic and aqueous leaf extracts, while phytosterols were only detected in the ethanolic extract. Folin-Ciocalteu assay determined the total phenolic content in gallic acid equivalents (GAE) to be $85.86{\pm}3.71$ and $32.32{\pm}1.01mg\;GAE/100g$ dried sample for the ethanolic and aqueous extracts, respectively. The total phenolic content in quercetin equivalents (QE) was $74.44{\pm}3.11$ and $29.43{\pm}0.85mg\;QE/100g$ dried sample for the ethanolic and aqueous extracts, respectively. The radical scavenging activity of the different solvent fractions containing varying concentrations of the extract was determined using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. The ethyl acetate and 1-butanol fractions were found to have the highest radical scavenging activity. Mineral analysis via Energy Dispersive X-Ray Spectrometry (EDS) of the ash of G. levis leaves showed that Si is the major component, followed by K and Mg. These results point to the potential of G. levis leaves as a source of minerals and bioactive compounds with medicinal value.

• Journal of the Korea Institute of Military Science and Technology
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• v.5 no.3
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• pp.113-119
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• 2002

A target adaptive guidance(TAG) algorithm is proposed employing the near-zone signal that can be measured from an infrared seeker. The guidance order is composed of a conventional PNG command and an additional command to be calculable from an additional LOS rate between a hot point of target and a required intercept point. The characteristic of the near-zone signal is similar to that of LOS rate that is inversely proportional to the square of time-to-go. Hence the proposed scheme can be applied to real systems with no estimator for time-to-go. From analysis results on the miss distance with perfect missile and perfect seeker, it follows that the proposed TAG algorithm guarantees missile to be ideally guided to the required intercept point. And it is less affected by the TAG start time and a proportional navigation ratio than other TAG schemes using a LOS rate such as a step bias or a ramp bias.

• Journal of Korean Society of Transportation
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• v.30 no.5
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• pp.23-31
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• 2012

The objective of this study is to develop the design criteria of traffic island considering pedestrian level of service (LOS). In pursuing the above, this study gives particular emphasis to suggesting the minimum design space of traffic island in order to maintain pedestrian LOS C and D, and the critical pedestrian traffic volume that reflects the intersection geometry (2 lanes per direction) through the simulation analysis. The main results are as follows. First, the spaces of 160 traffic islands, which meet the pedestrian LOS C and D and reflects the pedestrian traffic volume by signal cycle, are drawn by using a commercial simulator VISSIM. The relevant spaces of traffic island in terms of both the pedestrian LOS and the pedestrian traffic volume are evaluated to range from $3.0m^2$ to $41m^2$. Second, the critical pedestrian traffic volume for the operation of traffic island is evaluated to be 1,000-1,300 person/hour at LOS C and 1,600-1,800 person/hour at LOS D, respectively, when a cycle of 120-150 seconds were applied to a intersection with two lanes per direction.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.103-104
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• 2006

In this paper, we analyze the UAV datalink design with calculating link budget of long-distance (200 km) Ku-band LOS wireless link. We calculate C/N of the real system and compare it with the required C/N, using the CCIR reports. In the rainy day of summer on the Korean peninsula, to maintain percent reliability 90% and BER 10^(-5) together, link budget of uplink of the system has a lot of margin at 200 km, link budget of downlink using the block turbo code is enough for distance 200 km.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.216-221
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• 2002

A spherical Earth surface is used fur realistic analysis of the geometrical performance characteristics about the variation of satellite altitude and 2-dimensional line-of-sight(LOS) tilt angle in a satellite imager using Time Delay and Integration(TDI) technique with fixed integration time. In the spherical Earth surface model TDI synchronization using LOS tilt is investigated as a solution to compensate geometric performance degradation due to altitude decrease. This result can be used fur a TDI CCD imager with variable integration time in a certain as well.