• Title/Summary/Keyword: environmental controls

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Parameter Estimation of 2-DOF Dynamic System using Particle Filter (파티클 필터를 이용한 2 자유도 동역학 시스템의 파라미터 추정)

  • Kim, Tae-Yeong;Chong, Kil-To
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.2
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    • pp.10-16
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    • 2012
  • Currently, the majority of systems which are non-linear are in need of the correct system equations for controlling and monitoring. Therefore, the correct estimation of parameters is crucial. Generally, parameters are changed due to system deterioration or sudden environmental alterations. Given the limitations of system monitoring unstable controls can arise. In the following paper, the parameter estimation method is proposed using software filters to combat these system instabilities. For dynamic instances, a powerful particle filter is used to control the nonlinear and noisy environments in which they take place. Using a setup simulation comprised of a slider and pendulum, the state variable of noise is obtained. After collecting the data, the proposed algorithm is used to estimate both the state variable and its parameters. Finally, these results are checked with correct parameter estimations to evaluate and verify the algorithms performance.

Research in Physiology Signal Change of Thermal-Comfort Evaluation by Air Conditioner Temperature Change (에어컨 온도변동에 따른 온열쾌적감 평가 및 생리신호 변화에 관한 연구)

  • Kim, Hyung-Chul;Kum, Jong-Su;Shin, Byeong-Hwan;Chung, Yong-Hyun
    • Journal of Fisheries and Marine Sciences Education
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    • v.18 no.1
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    • pp.11-18
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    • 2006
  • Man has always striven to create a thermally comfortable environment. This is reflected in building traditions around the world - from ancient history to present day. Today, creating a thermally comfortable environment is still one of the most important parameters to be considered when designing buildings. It is defined in the ISO 7730 standard as being "That condition of mind which expresses satisfaction with the thermal environment". A definition most people can agree on, but also a definition is not easily converted into physical parameters. Thermal comfort is a matter of many physical parameters, and not just one, as for example the air temperature that is set by air-conditioner. The most important matter Today's common offices and homes are only depending on air-conditioning as a cooling system during the summer. This kind of system tends to be focused on the person who controls it and those who are around the air-conditioner while thermal-comfort is neglected. Futhermore, the people's body conditions are not considered during each time that beginning, middle, last of the air-conditioning which causing displeasure of the residents more and more. This kind of operating system is set for a long time may causes unbalanced air condition and man's psychologic displeasure goes to increase.

A Study of Engineering Properties of Rock Mass Weathered by Sea water (해수에 의한 암반 풍화의 공학적 특성 연구)

  • Choi Kang-Il;Kang Coo-Won;Go Chin-Surk
    • Explosives and Blasting
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    • v.23 no.1
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    • pp.9-17
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    • 2005
  • This study is to clarify the comparative relationship and mechanical anisotropy of granite distributed in the Nam-weon on the subject of weathered rock mass sea water surroundings. Artificial weathering test is defined as a test, which controls the weathering rate and agents by controlling the weathering rate and agents by artificial environmental of salt water. Increased weathering degree is large indicated by weathering salt water, such as apparent specific gravity, absorption, porosity, uniaxial compression strength, P-wave velocity, slake durability, shore hardness, indirect tensile strength(brazilian test) and cohesion were measured. As the Weathering salt water proceeds, cracks develope increasingly. A number the cracks affect the rock deformation. Therefore, stress-strain curve of weathered salt water rock in one confined state are quite differ from weathered fresh water rock those. A reason of their deformation type is the formation of micro-cracks and potential porosity caused by artificial weathering test.

A Study on the Suitability of the Mohr-Coulomb Model for Numerical Analysis of Ground Excavation (지반굴착 시 Mohr-Coulomb 모델 적합성에 관한 수치해석적 분석)

  • Lee, Jonghyun;Jin, Hyunsik;An, Joonsang;Baek, Yong;Yoon, Hyeongsuk
    • The Journal of Engineering Geology
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    • v.30 no.1
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    • pp.1-15
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    • 2020
  • The Mohr-Coulomb model is mainly used in evaluating the behavior of the ground in numerical analyses of domestic ground excavation. This study analyzes its limitations and compares its numerical results with the hyperbolic model, a model that closely follows actual ground behavior during excavation. Recent applications of the Mohr-Coulomb model in Korea have tended to impose arbitrary special boundary conditions to control the problem of excessive heaving of the ground excavation surface. This adjustment only controls the size of the heaving of the excavation surface, implying that the ground behavior is distorted from the actual behavior. This study compares results from the hyperbolic model (hardening soil model) and the Mohr-Coulomb model, and confirms that the hyperbolic model provides both a more-suitable solution to the problem of heaving during excavation and the actual stress-strain behavior. In numerical analyses of ground excavation, the hyperbolic model is expected to give results consistent with the actual ground behavior.

Chromium and nickel concentrations in air and in serum of workers in chromium and nickel electroplating plants (도금업 근로자의 혈청과 공기중 크롬 및 니켈 농도)

  • Choi, Ho Chun;Kim, Hae Jeong;Chung, Ho Keun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.1 no.2
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    • pp.117-127
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    • 1991
  • The exposure level of chromium and nickel for chrome and nickel plating workers were evaluated. Chromium and nickel concentrations in serum from 82 exposed workers and 66 controls, who were not exposed occupationally to metals, were analyzed by flameless atomic absorption spectrophotometry. The results were as follows : 1. The recovery percent of chromium and nickel concentrations in personal air samples were 95-108.2%, 88.0-107.7%, precisions (C.V., %) were 2.7-3.1%, 2.1-4.4%. respectively. 2. The recovery percent of chromium and nickel concentrations in serum were 93.6-106.4%, 91.3-107.9% and precisions (C.V. %) were 1.1-7.6%, 2.4-5.4% respectively. 3. The exposure level of chromium and nickel concentrations in the place of preparation process were $2.0{\pm}2.00{\mu}g/m^3$, chromplating were $35.7{\pm}53.07{\mu}g/m^3$, $2.8{\pm}3.42{\mu}g/m^3$, nickelplating were $4.6.0{\pm}5.8{\mu}g/m^3$, $18.62{\pm}4.41{\mu}g/m^3$, and covering were $2.9{\pm}2.02{\mu}g/m^3$, $1.1{\pm}0.47{\mu}g/m^3$ respectively. There were significant difference of concentrations for chromium and nickel in workplaces by groups statistically. 4. Chromium concentrations in serum of exposed group and control were $0.68{\pm}0.399{\mu}g/l$, $1.41{\pm}0.748{\mu}g/l$, respectively. There were significant difference of concentrations for chromium and nickel in serum by groups statistically. 5. Chromium and nickel concentrations in serum of exposed group were not significant by workplaces.

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Environmental Impacts of Stone Quarry Exploitation - Aquatic Macroinvertebrate Community and Quarry Locality (수생태계에 미치는 석산개발의 영향 - 생물군집과 입지유형을 중심으로)

  • Lee, Sung Jin;Kim, Myoung Chul;Kim, Ji Young;Ro, Tae Ho
    • Journal of Korean Society on Water Environment
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    • v.21 no.4
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    • pp.368-378
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    • 2005
  • Inorganic matters originated from stone quarries and manufacturing plants could alter the ecological characteristics of adjacent aquatic systems, especially the structure and function of benthic macroinvertebrate community. In such situation, the locality of stone quarry and the quantity of inorganic matters would be important factors that determined the disturbing strength to the benthic macroinvertebrate community. Locality patterns of stone quarries were classified into 3 types in relation to the stream ecosystem; stream-proximity, upstream-inclusion and tributary-inclusion type. In the result of species:abundance analysis, stone quarry B (upstream-inclusion type) showed geometric distribution, while others showed broken-stick distribution pattern. The benthic macroinvertebrate communities closer to stone quarries showed smaller species numbers and standing crops among all types of stone quarries. However the values of species evenness index were not seriously different between controls and directly affected sites. These results indicated that the effect of inorganic disturbance would differ from those of organic pollution that induced the highly dominant state occupied by tolerant species. Number of occurred species, standing crops, community indices and biotic indices indicated that the community of upstream-inclusion type was the most seriously damaged from the inorganic disturbance, and the community would be very simple and unstable. Tributary-inclusion stone quarry heavily damaged to tributary system in biologically, but influence to the main stream seemed to be depended on the scale of main stream. Among 3 types of stone quarry localities, stream-proximity type induced the least damages to benthic macroinvertebrate community, though the degrees of damage were different along with distances between stream and stone quarry.

Design and Load Map of the Next Generation Convergence Security Framework for Advanced Persistent Threat Attacks

  • Lee, Moongoo
    • IEIE Transactions on Smart Processing and Computing
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    • v.3 no.2
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    • pp.65-73
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    • 2014
  • An overall responding security-centered framework is necessary required for infringement accidents, failures, and cyber threats. On the other hand, the correspondence structures of existing administrative, technical, physical security have weakness in a system responding to complex attacks because each step is performed independently. This study will recognize all internal and external users as a potentially threatening element. To perform connectivity analysis regarding an action, an intelligent convergence security framework and road map is suggested. A suggested convergence security framework was constructed to be independent of an automatic framework, such as the conventional single solution for the priority defense system of APT of the latest attack type, which makes continuous reputational attacks to achieve its goals. This study suggested the next generation convergence security framework to have preemptive responses, possibly against an APT attack, consisting of the following five hierarchical layers: domain security, domain connection, action visibility, action control, and convergence correspondence. In the domain, the connection layer suggests a security instruction and direction in the domains of administrative, physical and technical security. The domain security layer has consistency of status information among the security domain. A visibility layer of an intelligent attack action consists of data gathering, comparison and decision cycle. The action control layer is a layer that controls the visibility action. Finally, the convergence corresponding layer suggests a corresponding system of before and after an APT attack. The administrative security domain had a security design based on organization, rule, process, and paper information. The physical security domain is designed to separate into a control layer and facility according to the threats of the control impossible and control possible. Each domain action executes visible and control steps, and is designed to have flexibility regarding security environmental changes. In this study, the framework to address an APT attack and load map will be used as an infrastructure corresponding to the next generation security.

Role of Vitamin D Deficiency and Lack of Sun Exposure in the Incidence of Premenopausal Breast Cancer: a Case Control Study in Sabzevar, Iran

  • Bidgoli, Sepideh Arbabi;Azarshab, Hamid
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3391-3396
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    • 2014
  • Background: Vitamin D has been suggested as one of the critical factors for female reproductive health with protective activities against different cancers but there are conflicting facts regarding its role on breast cancer without any clear data on premenopausal cases. This study aimed to evaluate the role of vitamin D from dietary sources and sunlight exposure on the incidence of premenopausal breast cancer. Materials and Methods: We conducted a case control study on 60 newly diagnosed premenopausal breast cancer patients and 116 normal women who lived in Sabzevar and surrounding villages in Razavi, Khorasan, a rural and conservative area of Iran. Results: The mean concentrations of 25-OH vitamin D in cases and controls were $15.2{\pm}8.15$ vs $15.5{\pm}7/45ng/ml$, both well below normal values elsewhere. In fact 50% of analyzed individuals showed very severe or severe vitamin D deficiency and the rest (25%) were detected in suboptimal levels. Although the lack of vitamin D and calcium supplementation increased slightly the risk of premenopausal breast cancer (p=0.009, OR=1.115, CI 95%=1.049-1.187), higher prevalence of weekly egg consumption (86.66% vs 96.55%, p=0.023, OR=0.232, CI 95% 0.065-0.806) showed a slight protective role. The last but the most important risk factor was lack of sunlight exposure because the breast cancer patients had total body coverage from sun (p=0.007, OR=10.131, CI 98% 0.314-78.102). Conclusion: This study pointed out the role of vitamin D and other possible risk factors on the development and growth of breast tumors in this special geographical region. Although this study has revealed the interactions between hormonal and environmental factors in this province of Iran, understanding the deficiency pattern and its contribution to other lifestyle factors elsewhere is also necessary.

Role of Household Exposure, Dietary Habits and Glutathione S-Transferases M1, T1 Polymorphisms in Susceptibility to Lung Cancer among Women in Mizoram India

  • Phukan, Rup Kumar;Saikia, Bhaskar Jyoti;Borah, Prasanta Kumar;Zomawia, Eric;Sekhon, Gaganpreet Singh;Mahanta, Jagadish
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.7
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    • pp.3253-3260
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    • 2014
  • Background: A case-control study was conducted to evaluate the effect of household exposure, dietary habits, smoking and Glutathione S-Transferases M1, T1 polymorphisms on lung cancer among women in Mizoram, India. Materials and Methods: We selected 230 newly diagnosed primary lung cases and 460 controls from women in Mizoram. Multivariate logistic regression analysis was performed to estimate adjusted odds ratio (OR). Results: Exposure of cooking oil fumes (p<0.003), wood as heating source for cooking (p=0.004), kitchen inside living room (p=0.001), improper ventilated house (p=0.003), roasting of soda in kitchen (p=0.001), current smokers of tobacco (p=0.043), intake of smoked fish (p=0.006), smoked meat (p=0.001), Soda (p<0.001) and GSTM1 null genotype (p=0.003) were significantly associated with increased risk of lung cancer among women in Mizoram. Significantly protective effect was observed for intake of bamboo shoots (p=<0.001) and egg (p<0.001). A clear increase in dose response gradient was observed for total cooking dish years. Risk for lung cancer tends to increase with collegial effect of indoor environmental sources (p=0.022). Significant correlation was also observed for interaction of GST polymorphisms with some of dietary habits. Conclusions: We confirmed the important role of exposure of cooking oil emission and wood smoke, intake of smoked meat, smoked fish and soda (an alkali preparation used as food additives in Mizoram) and tobacco consumption for increase risk of lung cancer among Women in Mizoram.

Lack of Association of BRCA1 and BRCA2 Variants with Breast Cancer in an Ethnic Population of Saudi Arabia, an Emerging High-Risk Area

  • Hasan, Tarique Noorul;Shafi, Gowhar;Syed, Naveed Ahmed;Alsaif, Mohammed Abdullah;Alsaif, Abdulaziz Abdullah;Alshatwi, Ali Abdullah
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.5671-5674
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    • 2013
  • Incidence of breast cancer shows geographical variation, even within areas of ethnic homogeneity. Saudi Arabia has witnessed an increase in occurrence of breast cancer in its unexplored ethnic populations over the past few years. We aimed at determining whether any association exists between single nucleotide polymorphisms in breast cancer associated gene 1 (BRCA1) and breast cancer associated gene 2 (BRCA2) and the risk of breast cancer. TaqMan based Real Time Polymerase chain reaction genotyping assays were used to determine the frequency of single nucleotide polymorphisms in BRCA1 (rs799917) and BRCA2 (rs144848) in a group of 100 breast cancer patients and unaffected age matched controls of Saudi Arabian origin. The present data revealed that neither BRCA1 nor the BRCA2 studied variant show any significant association with the disease. This study failed to find any role of the concerned variants in breast cancer either as risk or as prognostic factors. The small number of patients registered was one of the limitations of this study. In summary, comparison of mutation profile with other ethnic populations and regions reflected both differences and similarities indicating co-exposure to a unique set of risk factors. The differences could be due to exposure to particular environmental carcinogens; different lifestyle, reproductive pattern; dietary or cultural practices of Saudi Arabian women that need further investigations.