• Journal of Korean Society for Atmospheric Environment
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• v.18 no.6
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• pp.437-452
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• 2002

The Metropolitan Tracer Experiment (METREX) was performed over the Washington, D.C. area using two inert, non-deposition perfluorocarbon gases for over 1 year period (November 1983∼December 1984). Two perfluorocarbon gas tracers (PDCH, PMCH) were released simultaneously at intervals of every 36 hours for 6 hours, regardless of the meteorological conditions in metropolitan area. Samples were collected continuously for 8 hours at a central downtown and two adjacent suburban locations. Monthly air samples were collected at 93 sites across the whole region (at urban, suburban, and rural locations). The purpose of this study is to simulate INPUFF and ISCST model using METREX data, and to compare calculated and observed concentrations. In the case of INPUFF simulation, two meteorological input data were used. One is result data from wind field model which was calculated by diagnostic wind model (DWM), the other is meteorological data observed at single station. Here, three kinds of model calculation were performed during April and July 1984; they include (1) INPUFF model using DWM data (2) INPUFF model using single meteorological data (3) ISCST model. The monthly average concentration data were used for statistic analysis and to draw their horizontal distribution patterns. Eight-hour-averaged concentration was used to describe movement of puff during the episode period. The results showed that the concentrations calculated by puff model (INPUFF) were better than plume model (ISCST). In the case of puff model (INPUFF), a model run using wind field data produced better results than that derived by single meteorological data.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.543-546
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• 2015

There have been subway conflagrations such as Daegu subway conflagration at 2003, Washington D.C conflagration last month and so on. Compared to that, proper evacuation route is far from satisfactory. So this paper suggests optimized route when subway's passengers evacuate from passenger cars. For conducting our experiment, We made temporarily a model of subway station which is made up with 8 passengers cars and 3 exits. Using genetic algorithm, we found the optimized route that first and second passenger cars are optimized to first exit and third, fourth, fifth and sixth passengers cars are optimized to second exit and finally seventh, eighth passengers cars are optimized to third exit. It is expected that real subway station is applied to our experiment by developing passenger distribution algorithm.

• Journal of The Korean Association For Science Education
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• v.24 no.1
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• pp.63-75
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• 2004

The purpose of this study is to explore characteristics of on-line teaching materials on websites of natural history museums, particularly with regard to educational perspectives and the nature of science. The target resources were selected from the websites of the Natural History Museum in London, the Australian Museum in Sydney, the Field Museum of Natural History in Chicago, and the Smithsonian Museum in Washington D.C.. A total of twelve on-line resources from these museums used in this study were selected as representative informal science teaching materials. For the investigation, this study developed a checklist with a total of nine items that were grounded on mostly reviewing previous literature and articles focusing on educational perspectives of natural history museums and science centers. Exciting and positive results were found in all four museums. The analyses, however, indicated weaknesses as well as strengths in on-line resources regarding their usages as informal science teaching venues.

• Advances in materials Research
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• v.12 no.2
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• pp.119-131
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• 2023

The development of sustainable composites materials, from recycled polymeric materials and waste from the wood industry and stone processing, allows reducing the volume of these by-products, minimizing impacts on health and the environment. Nowadays, Polypropylene (PP) is the most recycled polymer in industry, while the furniture industry has increasingly used timber felled from sustainable forest plantations as a eucalypt. The powder tailing from the ornamental stone extraction and processing industry is commonly disposed of in the environment without previous treatment. Thus, the technological option for the development of composite materials presents itself as a sustainable alternative for processing and manufacturing industries, enabling the development of new materials with special technical features. The results showed that powder granite particles may be incorporated into the polypropylene matrix associated with short eucalyptus fibres forming green hybrid composites with potential application in structural engineering, such as transport and civil construction industries.

• Asia pacific journal of information systems
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• v.29 no.3
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• pp.448-467
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• 2019

In a new age of smart tourism, free independent travelers (FITs) choose their travel routes in a more diversified and less predictable way with the aid of smart services. This paper focuses on the movements of Chinese outbound FITs in the U.S. in the year of 2018. 110 places to visit (destinations) extracted from 122 travel routes recommendations on Qyer.com, a major online travel community in China, are analyzed with social network analysis (SNA). Based on the results of SNA, employing degree centrality, eigenvector centrality, betweenness centrality, network visualization, and cluster diagram methods, some preferred cities and natural attractions outside city centers (i.e., New York City (NYC), Los Angeles, San Francisco, Washington D.C., and Niagara Falls) are identified. Moreover, it is found that NYC in the East and Los Angeles in the West play a major role in the movements of Chinese FITs. This study contributes to the body of knowledge on tourist destination movements and provides valuable implications for smart service development in the tourism and hospitality industry.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2203-2207
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• 2015

Background: Breast conservative surgery (BCS) followed by radiotherapy is the standard approach in management of stage I-II breast cancer. Several factors can affect cosmetic outcomes. The aim of this study was to evaluate the cosmetic results of BCS and influencing factors in the Iranian Breast Cancer Research Center. Materials and Methods: Patients who had undergone BCS were included. Photographs were taken of both breasts of the patients in three aspects and were evaluated by three specialists. The cosmetic scores were calculated based on a standard questionnaire. The data were analyzed using univariate and multivariate regression for relationships between cosmetic scores and clinical data. Results: A total number of 103 patients were included in the study. Mean age and BMI of the patients were $46.8{\pm}8.9$ and $28.1{\pm}3.9$, respectively. Breast cup sizes C and D accounted for 74.7% of the study group. The mean cosmetic score obtained from three referees was 5.72+2.06, consisting of 35.9% excellent-good, 35% moderate, and 29.1% unsatisfactory results. Patient BMI, volume of the resected tissue and breast cup size (D) showed significant correlation with the cosmetic score. On multivariate regression analysis, cosmetic score and BMI (p=0.022,) as well as breast cup size (p=0.040), remained significant. Conclusions: Immediate or delayed symmetrization of the breasts is suggested during breast conservative surgery, meanwhile performing oncoplastic techniques to improve the results significantly. Also it is suggested to discuss anticipation of less satisfactory results with patients having higher BMI and large breast cup size.

• 대한예방의학회:학술대회논문집
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• 1994.02b
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• pp.206-233
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• 1994

The Medical Research Council has for some years encouraged collaborative clinical trials in leukaemia and other cancers, reporting the results in the medical literature. One unreported result which deserves such publication is the development of the expertise to design and analyse such trials. This report was prepared by a group of British and American statisticians, but it is intended for people without any statistical expertise. Part!, which appears in this issue, discusses the design of such trials; Part II, which will appear separately in the January 1977 issue of the Journal, gives full instructions for the statistical analysis of such trials by means of life tables and the logrank test, including a worked example, and discusses the interpretation of trial results, including brief reports of particular trials. Both parts of this report are relevant to all clinical trials which study time to death, and would be equally relevant to clinical trials which study time to other particular classes of untoward event: first stroke, perhaps, or first relapse, metastasis, disease recurrence, thrombosis, transplant rejection, or death from a particular cause. Part I, in this issue, collects together ideas that have mostly already appeared in the medical literature, but Part II, next month, is the first simple account yet published for non-statistical physicians of how to analyse efficiently data from clinical trials of survival duration. Such trials include the majority of all clinical trials of cancer therapy; in cancer trials, however, it may be preferable to use these statistical methods to study time to local recurrence of tumour, or to study time to detectable metastatic spread, in addition to studying total survival. Solid tumours can be staged at diagnosis; if this, or any other available information in some other disease is an important determinant of outcome, it can be used to make the overall logrank test for the whole heterogeneous trial population more sensitive, and more intuitively satisfactory, for it will then only be necessary to compare like with like, and not, by chance, Stage I with Stage III.

• 전기의세계
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• v.2
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• pp.6-14
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• 1949

Telemetering may be described as the art of metering at a considerable distance those quantities which are ordinarily encountered in industry, and in the generation of electric power. It is in the production of electric power that telemetering is particularly important, for it permits the system operator, or load dispatcher, to have before him at all times a continuous graphic record of the power output of each individual generating station together with an automatically made continuous graphic record of the total system output. There desired individual graphic records may be obtained showing power flow in or out, on important tie lines, etc. Such arrangements have the very great advantage that loads may be assigned to each generating station so that the best over-all system economy may be obtained and the system operator at all times may see with his own eyes that loads scheduled are actually held at the various stations. Moreover, with such equipment, in the event of system or station trouble the load dispatcher can see exactly what station, or stations, are affected and to what extent, without having to get in touch with anyone by telephone. Decisions can, therefore, be quickly reached for rescheduling the load. One of the most accurate and reliable telemetering systems is based on the use of potentiometric circuits, the fundamentals of which are discussed below. A member of such telemetering systems have been installed for the Boston Edicon Co., Boston, Massachusetts, the Consolidated Edison Co. of New York City. The Public Service Gas & Electric Co. of Newark, new Jersey. The Philadelphia Electric Co. for Philadelphia, Pennsylvania, and the Pennsylvania Railroad Co. for their electrified zone between New York and Washington a distance of over 200 miles. The scale of the totalizing recorder for the New York area is 3,000,00 KW. That of the totalizing recorder for the Philadelphia area is 2,000,000 KW. The initial installation using this type of equipment described was placed in service for the Philadelphia Electric Co. in 1923. All of the original recording instruments are still in service, later instruments have been added to take care of additions to the power system and naturally these later recorders have incorporated in those refinements in design made since the earlier ones were manufactured. Many other installations of similar equipment have been made in the United States in various locations such as at St. Louis, on the West Coast, at Baltimore and in Washington, D.C. While the use of these basic potentiometric circuits involves the use of continuous metallic circuits of good insulation resistance and free of grounds, nevertheless, intermediate transmission links, involving and impulse method suitable for use on telephone Morse carrier channels is available. This same method may be employed on power line carrier systems and is also suitable for use on beam type microwave transmission. Many impulse type units are also used as a link in these potantiometric methods. For the sake of brevity a description is given only of these basic potentiometric circuits. If there is sufficient interest in Korea, a further paper can be given covering those impulse circuits also.

• Journal of the Korean Geotechnical Society
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• v.18 no.3
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• pp.51-59
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• 2002

This paper deals with development of a damage risk assessment system for adjacent buildings to under-passing tunnel face considering 3D-ground movement. The system consists of building and ground information module, monitoring data module, settlement evaluation module, and building damage risk assessment module. The major modules, settlement evaluation module and building damage assessment module, are based on settlement estimation model suggested by Attewell et al (1982) and the building damage assessment method by Mair et al. (1996). After estimating 3D-ground movements due to tunneling with settlement evaluation module, damage assessment far buildings is performed using building damage risk assessment module. The developed system has two major functions; 1) calculation of 3D-settlement with ground loss ($V_{s}$)or maximum settlement ($w_{max}$) and inflection point (i) using various empirical formulae, monitoring data, numerical results, and so on; 2) assessment of damage risk for adjacent buildings of arbitrary section with position change of tunnel face. The field data given by Boscadin and Cording (1989) leer the case of two-storied masonry building near the Metro tunnel in Washington D.C. was simulated to verify the applicability of the developed system.

• Environmental Analysis Health and Toxicology
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• v.14 no.1_2
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• pp.1-12
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• 1999

Recently, several new methods for the detection of genetic damages in vitro and in vivo based on molecular biological techniques were introduced according to the rapid progress in toxicology combined with cellular and molecular biology. Among these methods, mouse lymphoma thymidine kanase (tk) gene forward mutation assay, single cell gel electrophoresis (comet assay) and transgenic animal and cell line model as a target gene of lac I (Big Blue) and lac Z (Muta Mouse) gene mutation are newly introduced based on molecular toxicological approaches. The mouse lymphoma tk$\^$+/-/ gene assay (MOLY) using L5178Y tk$\^$+/-/ mouse lymphoma cell line is one of the mammalian forward mutation assays, and has many advantages and more sensitive than hprt assay. The target gene of MOLY is a heterozygous tk$\^$+/-/ gene located in 11 chromosome, so it is able to detect the wide range of genetic changes like point mutation, deletion, rearrangement, and mitotic recombination within tk gene or deletion of entire chromosome 11. The comet assay is a rapid, simple, visual and sensitive technique for measuring and analysing DNA breakages in mammalian cells, Also, transgenic animal and cell line models, which have exogenous DNA incorporated into their genome, carry recoverable shuttle vector containing reporter genes to assess endogenous effects or alteration in specific genes related to disease process, are powerful tools to study the mechanism of mutation in vivo and in vitro, respectively. Also in vivo acridine orange supravital staining micronucleus assay by using mouse peripheral reticulocytes was introduced as an alternative of bone marrow micronucleus assay. In this respect, there was an International workshop on genotoxicity procedure (IWGTP) supported by OECD and EMS (Environmental Mutagen Society) at Washington D. C. in March 25-26, 1999. The objective of IWGTP is to harmonize the testing procedures internationally, and to extend to finalization of OECD guideline, and to the agreement of new guidelines under the International Conference of Harmonization (ICH) for these methods mentioned above. Therefore, we introduce and review the principle, detailed procedure, and application of MOLY, comet assay, transgenic mutagenesis assay and supravital staining micronucleus assay.