• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.23 no.2
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• pp.1-14
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• 2024

The most optimal route-search algorithm thus far has introduced a method of applying node labels and link labels. Node labels consider two nodes simultaneously in the optimal route-search process, while link labels consider two links simultaneously. This study proposes a turn-label-based optimal route-search technique that considers two turns simultaneously in the process. Turn-label-based optimal route search guarantees the optimal solution of dynamic programming based on Bellman's principle as it considers a two-turn search process. Turn-label-based optimal route search can accommodate the advantages of applying link labels because the concept of approaching the limit of link labels is applied equally. Therefore, it is possible to reflect rational cyclic traffic where nodes allow multiple visits without expanding the network, while links do not allow visits. In particular, it reflects the additional cost structure that appears in two consecutive turns, making it possible to express the structure of the travel-cost function more flexibly. A case study was conducted on the metropolitan urban railway network consisting of transportation card terminal readers, aiming to examine the scalability of the research by introducing parameters that reflect psychological resistance in travel with continuous pedestrian transfers into turn label optimal path search. Simulation results showed that it is possible to avoid conservative transfers even if the travel time and distance increase as the psychological resistance value for continuous turns increases, confirming the need to reflect the cost structure of turn labels. Nevertheless, further research is needed to secure diversity in the travel-cost functions of road and public-transportation networks.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.2
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• pp.231-238
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• 2023

Since there is a limit to the physically visible horizon that sensors for autonomous driving can perceive, complementary utilization of digital map data such as a Local Dynamic Map (LDM) along the probable route of an Autonomous Vehicle (AV) is proposed for safe and efficient driving. Although the amount of digital map data may be insignificant compared to the amount of information collected from the sensors of an AV, efficient management of map data is inevitable for the efficient information processing of AVs. The objective of this study is to analyze the efficiency of information use and information processing time of AV according to the expansion of the active section of LDM-based static road and traffic information. To carry out this objective, a microscopic simulator model, VISSIM and VISSIM COM, was employed, and an area of about 9 km × 13 km was selected in the Busan Metropolitan Area, which includes heterogeneous traffic flows (i.e., uninterrupted and interrupted flows) as well as various road geometries. In addition, the LDM information used in AVs refers to the real high-definition map (HDM) built on the basis of ISO 22726-1. As a result of the analysis, as the electronic horizon area increases, while short links are intensively recognized on interrupted urban roads and the sum of link lengths increases as well, the number of recognized links is relatively small on uninterrupted traffic road but the sum of link lengths is large due to a small number of long links. Therefore, this study showed that an efficient range of electronic horizon for HDM data collection, processing, and management are set as 600 m on interrupted urban roads considering the 12 links corresponding to three downstream intersections and 700 m on uninterrupted traffic road associated with the 10 km sum of link lengths, respectively.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.218-229
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• 2015

The proficiency testing for the residue laboratories of pesticide registration was conducted in order to improve the reliability and the ability for pesticide residue analysis. On November 2012 the testing was carried out using the soil collected and kept as the moistened state for five years, which was expected to very low residue levels of pesticides. The soil was fortified with azoxystrobin, imidacloprid and methabenzthiazuron in a manner similar to prepare soil samples for indoor soil degradation test, and then sub-samples were prepared for the distribution to participants. Some of them were randomly selected for confirm of homogeneity and to ensure the stability of samples at room temperature. Samples were consisted of two soils treated as different levels, one of which was used to the assessment and another used to confirm. In addition, provided three standard solutions, respectively concentration of 10 mg/L, and untreated soil. Forty eight institutions submitted results. The medians of results were used as the assigned values for pesticide residues. Fitness for purpose standard deviation of proficiency test was calculated by applying 20% RSD as the coefficient of variation allowed in the soil residue test. Z-score was applied for evaluation of individual pesticides, and the average of the absolute value of the Z-score for the overall assessment of pesticides. Laboratories evaluated the absolute value of the Z-score less than 2 to fit the case of azoxystrobin were 48, imidacloprid and methabenzthiazuron 46.

• Economic and Environmental Geology
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• v.38 no.2 s.171
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• pp.113-127
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• 2005

Cretaceous intrusive and extrusive rocks are widely distributed in the southwestern part of the Korean peninsula, possibly the result of intensive magmatism which occurred in response to subduction of the western proto-Pacific plate beneath the north-eastern part of the Eurasian plate. Geochemical and petrological study on the Cretaceous granitic rocks were carried out in order to constrain the petrogenesis of the granitic magma and to establish the paleotectonic environment of the area. Whole rock chemical data of the granitic rocks from the study area indicate that the all the rocks have characteristics of calc-alkaline series in the subalkaline field. The overall geochemical features show systematic variations in each granitic body, but the source materials of each granitic body are thought to have been different in their chemical composition. Higher values of $Fe_2O_3/FeO$ of the granitic rocks in the western area suggest that the granitoids had been solidified under highly oxidizing environment. The granitic bodies in the eastern area also show higher contents of Li, Ni, Co, Sr, Cr, Sc and lower Rb and Nb compared to the those of the western area. Chondrite normalized REE patterns show generally enriched LREE and strong negative Eu anomalies in the western wet while slight to flat Eu anomalies in the east-ern area. The REE and $(La/Lu)_{CN}$ of the granites are $60{\~}499ppm$ and $8.9{\~}66$ correspond to the range of the continental margin granite. On the ANK vs. ACNK and tectonic discrimination diagrams, parental magma type of the granites corresponds to I-type, VAG and syn-collision granite. Interpretations of the chemical characteristics of the granitic rocks favor their emplacement in a compressional tectonic regime at continental margin during the subduction of proto-Pacific plate.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.3
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• pp.26-38
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• 2011

The purpose of this study was to analyze the commemoration culture of Vietnam War Memorials (VWM) in Vietnam. Through site survey, the researcher selected 23 VWM in Vietnam and analyzed 5 categories: memorial type, design concept and narratives, location and spatial form, landscape elements, and content expressed in landscape details. The results are as follows: 1. Because of the long, drawn out Vietnam War, which lasted from 1955 to 1975, VWM were divided into 10 types mainly as soldier cemeteries based on a traditional memorial style, battlefields and places of tragedies considering sense of place, war museums representing victory and atrocity in war, and peace parks promoting reconciliation and peacemaking. 2. The analysis revealed that the main concepts and narratives of VWM were to value the victims of the Vietnam War, remember soldiers' contributions, highlight the victory in war and resistance to the United States, and express a sense of place. Peacemaking applied only to My Lai Peace Park and Han-Viet Hoa Binh Cong Vien, built by international cooperation. 3. Cemeteries and appreciation memorials were designed to follow a traditional memorial space form that highly regard both axis and symmetry. The design concept at battlefields and places where tragedies occurred depended mainly upon a sense of place and used symbolic landscape elements to compensate for the undefined concept. 4. Sculptures and towers were mainly used to highlight war victory and resistance as the representative style of a Socialist country, weapons and pictures exhibited in war museums and battlefield showed the reality and strain of war. Symbolic elements of Buddhism and Confucianism were often introduced as a way to venerate the memory of deceased persons. 5. The state and heroic actions in the Vietnam War were realistically depicted on sculptures and walls. Also, the symbolic phrase, 'TO-QUOC-GUI-CONG' meaning 'our country remember your achievement', were written on the memorial tower and 'Quagmiire' was used to metaphorically represent the difficulties faced by the U.S. military on battlefields during the war and the uncertainly that pervaded U.S. society in those days. 6. In VWM, ideologies like nationalism, patriotism, socialism, capitalism were mixed and traditional cultures like Buddhism, Confucianism, Taoism were inherent. Differing from their Confucianism culture, war heroes, particularly including women, were often described by sculpture, monument, and pictures and the conflict in and outside the country regarding the Vietnam War was shown. Further study will be required to analyze design characteristics of VWM in the u.s. and to understand the difference in commemoration cultures between Vietnam and the U.S.

• 한국노년학
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• v.38 no.3
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• pp.705-723
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• 2018

In this study we review the selected articles on elderly health and medical care published in the Journal of the Korea Gerontological Society (JKGS) in the last 40 years, and make suggestions for future research directions for gerontological health and medical care issues. Of all the 40 year publications from volume 1 (1980) to 38 (2017), we first examined the 30th anniversary review on the subject of gerontological nursing care and healthcare policies published in JKGS from 1980 (vol. 1, No. 1) to 2008 (vol. 28, No. 2), and reviewed recent 237 researches of this decade (out of all 655 articles from 2008, vol. 28, No. 3 to 2017, vol. 38, No. 4). We could find the following trends. Firstly, the analysis of the primary authors in the past 10 years revealed that those in public health, nursing and other health-related including physical education areas have dealt the subjects focusing on physical health while those in social welfare mostly on mental health. That is, physical health has been the prime subject of researches in the health and medical care area. Secondly, in the same period quantitative researches were accounted for 89.9%, which is similar to the trend of the first 30 years 81.5 %. On the other hand, qualitative studies were only 11 cases and the focus group interview were the most frequently used method comprising 33.3% among them. Thirdly, the non-experimental researches in the past 10 years comprise 65.4%, which was 82.7% in 1980 2008 period, indicating the increasing trend in experimental researches to deal with the issues in medical and healthcare fields. Lastly, the subjects of the researches were mostly the elders who are healthy, residents of city areas, or home dwellers, and 60% of them were over 65 years old in the past 10 years while the proportion was 42.7% in the previous review period. 81.6 % of the researches in the past 10 years was dealing both genders, slightly decreased trend compared to 88.5% of the previous review period. This study reveals that the researches in non-experimental physical health remains the main stream of JKGS despite the efforts by some researchers to diversify the methods and subjects. Systematic and in-depth researches employing multidisciplinary, qualitative, longitudinal and meta-analytical approaches are called for to guide the gerontolgical health issues with preventive and proactive perspectives.