• Progress in Medical Physics
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• v.1 no.1
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• pp.109-122
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• 1990

A method of making inserts for shaped fields in electron beam therapy on the Mevatron KD 67-7467 Linear Acclerator is introduced. The inserts are made from an alloy called Lipowitz metal. These are designed to fit the inside of the standard Siemens cones. Studies have shown that this method does not adversely affect field flatness. However, if the ratio of shaped field to open field is greater than about 70%, the output dose is significantly changed by the inserts. Because the cone ratios for the fields do not follow the open cone ratio curves on the Mevatron KD 67-7467, we separated the cone ratio suggested by Biggs into two parts, the insert ratio and the cone factor. The dosimetry for these shaped beams has been investigated extensively.

• Korean Management Science Review
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• v.34 no.1
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• pp.27-45
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• 2017

The purpose of this study is to empirically analyze whether open innovation activities are significant and which methods are more effective in developing new businesses. Based on the latest technological innovation survey data of the Science and Technology Policy Institute, the results were analyzed by binary logistic regression analysis. As a result of the analysis, we confirmed that open innovation activities have a positive effect on the performance of developing new businesses. In the open innovation activities, Recruitment (invitation) of specialist in related fields, Business alliance technical agreement, Dispatch of personnel, M&A, Acquisitions identify related field trends showed more influence in order. It would be beneficial to improve the performance of developing new businesses with a low probability of success if utilize more effective innovation activities in developing new business in enterprises or organizations throughout this study.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1576-1589
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• 2006

Most of surface water ways in Egypt suffer from the infestation of aquatic weeds especially submerged ones which cause lots of problems for the open channels and the water structures such as increasing water losses, obstructing the water flow, and reducing the efficiency of the water structures. Accurate simulation of the water flow behavior in such channels is very essential for water distribution decision makers. Artificial Neural Network (ANN) has been widely utilized in the past ten years in civil engineering applications for the simulation and prediction of the different physical phenomena and has proven its capabilities in the different fields. The present study aims towards introducing the use of ANN technique to model and predict the impact of the existence of submerged aquatic weeds on the hydraulic performance of open channels. Specifically the current paper investigates utilizing the ANN technique in developing a simulation and prediction model for the flow behavior in an open channel experiment that simulates the existence of submerged weeds as branched flexible elements. This experiment was considered as an example for implementing the same methodology and technique in a real open channel system. The results of current manuscript showed that ANN technique was very successful in simulating the flow behavior of the pre-mentioned open channel experiment with the existence of the submerged weeds. In addition, the developed ANN models were capable of predicting the open channel flow behavior in all the submerged weeds' cases that were considered in the ANN development process.

• International Journal of Fluid Machinery and Systems
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• v.7 no.4
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• pp.174-182
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• 2014

The ultimate objective of this study is to develop a water turbine appropriate for low-head open channels to effectively utilize the unused hydropower energy of rivers and agricultural waterways. The application of a cross-flow runner to open channels as an undershot water turbine has been considered and, to this end, a significant simplification was attained by removing the turbine casing. However, the flow field of an undershot cross-flow water turbine possesses free surfaces, and, as a result, the water depth around the runner changes with variation in the rotational speed such that the flow field itself is significantly altered. Thus, clear understanding of the flow fields observed with free surfaces to improve the performance of this turbine is necessary. In this study, the performance of this turbine and the flow field were evaluated through experiments and numerical analysis. The particle image velocimetry technique was used for flow measurements. The experimental results reflecting the performance of this turbine and the flow field were consistent with numerical analysis. In addition, the flow fields at the inlet and outlet regions at the first and second stages of this water turbine were clarified.

• Journal of the Korean Society for information Management
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• v.40 no.4
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• pp.73-94
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• 2023

This study empirically analyzed the proportion and method of Open Access (OA) in Korea, China, Japan, the United States, United Kingdom based on the Web of Science (WoS) papers. In addition, through the verification of the moderating effect, it was verified whether there is a difference in the effect of the amount of citation depending on the maturity of OA according to the countries or academic fields. As a result of the analysis, the proportion of OA was the highest in the UK at 62.7%, and the lowest in China at 38.0%. Second, the UK and US had a high proportion of indicators through self-archiving and APC-based Gold Hybrid, while only the Gold indicators were found to be prominent in China and Korea. Third, in the UK, US and Japan, the higher the proportion of OA, the greater the effect of inducing the citations. However, Korea (B=-0.00003, p<0.01) and China (B=-0.00001, p<0.01) showed the opposite direction. In addition, in most academic fields, the OA proportion had an effect of inducing citation, but a negative effect was found in the engineering field (B=-0.00002, p<0.01).

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.22 no.3
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• pp.373-391
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• 2011

To understand the characteristics of open access journals in Korea, this research examined the 1,438 KCI journals in the fields of humanities, social sciences, natural sciences, engineering, medicine, agriculture & oceanography, art & sports, and interdisciplinary. 21% of the KCI journals are freely available at the publisher's websites or open access DBs(OA). 34% are available only in the commercial fulltext DBs(TA) and 34% combined TA and OA. 48% of the OA journals can be found on the free fulltext DBs and 52% are accessed on the publisher's websites. OA journals in humanities and social science are available mainly on the publisher's websites. As compare with this, OA journals of STM fields are available via the free fulltext DBs. Medicine(30%) and social sciences(25%) have the highest overall share of OA. There are field differences in the rate of OA journals. In the fields of social sciences and humanities, 15% of the journal are open access. In case of medicine field, 60% are open access journals. OA journals in natural science and engineering are each 33% and 24%.

• Korea Science and Art Forum
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• v.37 no.3
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• pp.135-145
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• 2019

IFC(Industry Foundation Classes) is used for information exchange in BIM-based collaboration process, and it does not secure reliability of information exchange results between fields due to structural limitations. In the end, it is a realistic problem that we have to use specialized BIM software by field, and we can not secure smooth interoperability in the process of information exchange and change. This study was conducted to find ways to secure the interoperability of BIM work between architecture and structure fields by utilizing Open Source provided by software developers to solve these problems. First, through expert survey and in-depth interview, information and improvement factors required in the process of collaboration between architecture and structure were derived. Second, in order to find a solution to the improvement factors, existing studies related to Open-API and domestic and overseas APIs were investigated and analyzed. Third, Ad-On was developed to secure interoperability by using Open API, mainly BIM S/W, which is mainly used in each field. As a result of the study, the possibility of securing interoperability through the management of the design change history between fields was confirmed by using API. It is judged that the application range of API will be expanded to the construction and maintenance field in the future. Therefore, in order to increase the usability for application diffusion, further research on interface improvement through user-centered verification is needed.

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.30-37
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• 2007

Pellets and prey remains were analyzed to compare diets and foraging tactics of Eurasian eagle owls (Bubo bubo) in two different habitat types: forested areas and open fields. Overall 150 prey items of three taxa were identified from 66 pellets and 82 prey remains, and the birds were the most important prey in biomass (78.04%) and in frequency (56.67%). Eurasian eagle owls frequently used rats (Rattus spp.), ring-necked pheasants (Phasianus colchicus), and stripped field mice (Apodemus agrarius), but the ring-necked pheasant was most important in biomass in both habitat types. The owls generally foraged various prey in biomass but the mean mass of vertebrate prey used by the Eurasian eagle owls was 503.3g in central Korea. According to the comparison of diets in the two different habitat types, the owls used bigger and more diverse prey in forested areas than in open fields. In forested areas, the Eurasian eagle owls frequently foraged the pheasants and Mandarin ducks (Aix galericulata), but they preferred prey of particular sizes to prey of particular taxa. In open fields, however, the owls showed opportunistic foraging tactics by selecting many small mammals such as rodents or a few large birds.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.138-151
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• 2013

This study was carried out to investigate the distribution and habitat types of prickly lettuce, Lactuca scariola of Europe origin for supplying the basic data of management plan. It showed fairly nation-wide distribution although excessive growth was rather limited in the wild. Its habitat types were divided into four types like open fields, roadsides, seashores and riversides. Species diversity examined by species rank-dominance curve tended to increase over riverside > seashores > open fields > roadsides. As a result of analyzing life form, therophytes were more than 50%, means that the habitats of L. scariola were disturbed by human activities etc. Urbanization Index was analyzed 9.1% in roadsides, 7.4% in seashores, 5.8% in open fields and riversides. It has high spread potential with a large number of wind-flying seed per plant. It was evaluated that prickly lettuce was mainly spread along the newly constructed road, expressway and invaded the original ecosystem in the cultivated land as weeds. But it has played a role as a pioneer species in open fields. It is recommended to remove where it has considerable impact on the native plant species of conservation value.

• International Journal of Advanced Culture Technology
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• v.8 no.2
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• pp.297-304
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• 2020

Recently, open source automatic machine learning solutions have been applied in many fields. To apply open source automated machine learning to real world problems, you need to write code with expertise in machine learning. Writing code without machine learning knowledge is challenging. To solve this problem, the automatic machine learning solutions provided by startups are made easy to use with a clean user interface. In this paper, we review automatic machine learning solutions of startups.