• Nuclear Engineering and Technology
• /
• v.52 no.6
• /
• pp.1252-1258
• /
• 2020

This study explores the ability of non-destructive assay techniques to detect a partial material defect in which 100 g of plutonium are diverted from the center of a 1000 g can of PuO₂ powder. Four safeguards measurements techniques: neutron multiplicity counting, calorimetry, gravimetry, and gamma ray spectroscopy are used in an attempt to detect the defect. Several materials are added to the partial defect PuO₂ can to replicate signatures of the diverted material. ²⁵²Cf is used to compensate for the doubles neutron counts, ²⁴¹Am is used to compensate for the decay heat, and aluminum is used to compensate for the weight. Although, the doubles and triples difference before and after diversion are statistically indistinguishable with the AWCC in fast and thermal mode, the difference in the singles counts are statistically detectable in both modes. The relatively short half-life of ²⁵²Cf leads to a decrease (three sigma uncertainty) in the doubles neutron counts after 161 days. Combining this with the precise quantity of ²⁴¹Am needed (10.7 g) to mimic the heat signature and the extreme precision in ²⁵²Cf mass needed to defeat neutron multiplicity measurements gives reassurance in the International Atomic Energy Agency's ability to detect partial material defects.

• Journal of Forest and Environmental Science
• /
• v.31 no.3
• /
• pp.225-234
• /
• 2015

Mangroves are important coastal ecosystems and are located at the inter-tidal zones of tropical and sub-tropical belts. The global mangrove forests are declining dramatically because of the conversion of forests to shrimp farming, over-exploitation, pollution and freshwater diversion. The Bangladesh Forest Department initiated mangrove afforestation throughout the coastal belts of Bangladesh in 1966 to provide better protection for the coastal communities. Up to 1990, 120,000 ha of mangroves had been planted and it is one of the largest coastal afforestaton programs in the world. The objective of this study is to exploit the spatial extent of mangrove plantation and their dynamics of changes over the last two decades using multispectral Landsat imagery. The study area covers the coastal areas of Bangladesh that is extended over the eastern part of Sundarbans up to Teknaf, the southern tip of mainland Bangladesh. Mangrove plantations were interpreted visually on computer screen and interactive delineation of forest boundary was done. The mangrove plantation area has been estimated as 32,725, 47,636 and 43,166 ha for the year of 1989, 2000 and 2010, respectively. Mangrove deforestation by human activity has increased almost six times in the recent decade in comparison to the previous one. The mangrove forest loss due to coastal erosion has slightly declined in the 2000s. Mangroves have been lost primarily because of agricultural expansion. The result of this investigation will be helpful to understand the dynamics of mangrove plantation and the main drivers of changes in this coastal ecosystem.

• Journal of the Korean Society of Costume
• /
• v.56 no.8 s.108
• /
• pp.45-59
• /
• 2006

The change into the information society converts people's daily lift into nomadic lifestyle, and this change of lifestyle needs to reinforce the portability in fashion. The purpose of this study is to know the historical diversion of the rallying system, characteristics and reason of this change after recognizing of the implication of fashion and portable methods. The carrying system from the primitive age to modern society was changed from use of body to designing potable equipments - belts, wrapping cloths, bags, pockets, etc. These are changed by modifying of the form of society and fashion. This change result from the development of technique, the entry of women in public affair, the change of life style, the impoverishment of nature. The carrying system of modern fashion means not only the spares in the clothing, but also a new attached system in which nomadic necessities are transformed or unified. The carrying system becomes one of the important details which designers cannot neglect in designing, and must be. developed with consideration of use and function.

• The Journal of Sustainable Design and Educational Environment Research
• /
• v.6 no.2
• /
• pp.53-65
• /
• 2007

Our society is changing into the society of knowledge and information since the advent of 21st century. This may require that schooling need to have a new paradigm. Korea has already entered into the aging society with the help of various population control policies such as birth control from 1960s, and is expecting to go into the so called ultra- aging society. Elementary and middle schools have been facing the rapid decrease in the number of students since the mid-1980s, which high schools are now confronting with. The present study investigates how to effectively utilize extra classrooms at schools. The present study offers eight basic directions that may help establish the utilization planning of extra classrooms. One direction is offering an appropriate space utilization environment, another is to present a plan for having special classrooms. Others are having multi-purpose classrooms, management on the unified rooms for library and audio-visual teaching, securing facilities rooms for the school staff. And others are the planning of the diversion of living space for improving sanitation and the provision of meals, the necessity of the extension or rebuilding of school buildings for other uses according to school development schemes, the utilization planning for community residents to which each school belong.

• Journal of environmental and Sanitary engineering
• /
• v.21 no.2 s.60
• /
• pp.11-19
• /
• 2006

Ran numerical analysis about simplicity warm current model (simple turbulence model) to examine closely distributed laying stress on NOx of contaminant that happen in downtown that building is massed and result is as following. Downtown building is massed and transfer of vehicles can know that frequent area receives greatly effect of building. Pollution displays class kind phenomenon striking in the building, class kind done pollution that show high density being mixed with pollution that happen in vehicles being flowed in again side know can. Divide velocity vector of pollution and density change to ancient city and did numerical analysis. Because NOx is flowed in diversion of water neighborhood by continuous this kind in Godo 20m point, density showed density of $0.0907mg/m^3s$, and can know that Banryuhyeon that Pollution strikes in the building at ancient city 30m point is decreased and approaches with freedom flowing without cooperation (cavity) phenomenon remarkably. Because pollution strikes in the building at distance shaft 383m point, class kind do phenomenon that know appeared notedly Nopeungeonmulgwanat between building pollution density $0.067mg/m^3$ head of a families high appear.

• Journal of Korean Institute of Fire Investigation
• /
• v.11 no.1
• /
• pp.155-166
• /
• 2007

This study is to deduce problems and grope for its solution by investigating the general operation status about the present fire investigation in Korea. As for the problems, this study is to point out that they are application of diversion by the function of law for fire investigation, execution of individualized fire investigation by each institution, total lack of information sharing system for fire investigation, and weakness of cause investigation for arson. The reform measures are as follows: the unity of law for fire investigation, joint investigation by the related institutions, early introduction of civil fire investigation expert system, extension of special research institutes for fire investigation, introduction of system for sharing information of fire investigation, and operation of fire investigation team for cause investigation for arson.

• Wind and Structures
• /
• v.26 no.2
• /
• pp.69-74
• /
• 2018

Nowadays, using math logic in great civil projects is considered by the clients to achieve the goals of project including quality optimization, costs, avoiding individual, emotional and political decision making, long-term and short-term goals and they are the main requirements of each project and should be considered by the decision makers to avoid the illogical decision making applied on the majority of civil projects and this imposes great financial and spiritual costs on our country. The present study attempts to present one of the civil projects (Ghasre Shirin storage dam) whose client was not ministry of energy for the first time and the short-term and long-term goals of the private sector were applied based on the triangle of quality, cost and time. Also, the math logic and model (multi-criteria decision making method and decision making matrix) is used in one of the most important sections of project, sealing element, policies and new materials (Geosynthetics) are considered and this leads to suitable decision making in this regard. It is worth to mention that this method is used for other sections of a dam including body, water diversion system, diaphragm and other sectors or in other civil projects of building, road construction, etc.

• The Journal of Information Systems
• /
• v.23 no.4
• /
• pp.1-24
• /
• 2014

This study is intended to examine two issues related with social media messages. At first, the authors investigate that how they can categorize messages in the social media and how corporate twitters and brand twitters communicate with consumers. Secondly, after dividing messages in the social media into several groups, the authors investigate how each type of messages differ one another in terms of the consumer response. For examining these research issues, the authors gather twitter message data of global top 100 brands and categorize messages into 5 types (i.e., interactivity, diversion, information sharing, promotional, content) based on the motivation of communication and the format of the messages. Especially, the authors use content analysis methodology, which is normally used as the qualitative approach, in order to identify the type of messages. Furthermore, the authors present interactivity type of messages can communicate better with consumers and induce more favorable responses from consumers in the social media than any other type of messages. This research can provide implications in terms of theoretical, methodological, and managerial perspective.

• Journal of the Korean Institute of Rural Architecture
• /
• v.9 no.3
• /
• pp.83-92
• /
• 2007

The importance of residents' participation has become more prominent to promote better living condition and quality of life in rural communities due to the skeptical views on the outcomes of the rural community supporting projects led by organizations and institutions. This study analyzes White Dandelion Eco-Village in Hoebuk Myeon, Boeun Kun, Chungbuk where community development is being done by its residents. By examining the formation background and the history of the village, and various participation forms and methods of the residents, I am to derive the ideal rural community development project led by the villagers themselves. To achieve successful supporting projects for rural communities by many different organizations and methods, it is necessary to have followings; residents' affectionate attentions for the community as well as good ideas and intentions, excellent leaders who gather all the efforts and transform them into good plans, well made strategies and continuous endeavor, and the diversion of thoughts of the supporting project experts and the organizations.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.37 no.3
• /
• pp.306-319
• /
• 2013

This study explores various issues of appearance management behavior for plus-size women in Korea with a focus on clothing. In-depth interviews and focused group interviews were conducted with 24 plus-size women. The interviews were recorded and the transcripts were analyzed based on grounded theory. Discomfort was the main phenomenon involving the experience of plus-size women related to appearance management. Psychological as well as physiological/physical discomfort, unmet needs (regarding clothing) and inconvenient shopping experiences were frequently mentioned. Causal conditions for discomfort were obesity, social stigma, and an underdeveloped clothing market for plus-size consumers. Interviewees developed strategies to cope with discomfort (suppressing clothing need, loss of interest in clothing, diversion from clothing needs, sole focus on physical comfort, dress-up and increase in shopping channels, and change in shopping patterns) that depended on contextual conditions (such as duration of obesity and attitudes of people) close to the interviewees. The discomfort of interviewees decreased or continued depending on if they became ambivalent about their obese condition, lost weight, or utilized plus-size specialty stores.