• Title/Summary/Keyword: Adverse conditions

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Damage Conditions of the Slope Structures due to ARD (산성암반배수에 의한 사면구조물의 피해 현황)

  • Park, Sam-Gyu;Kim, Jae-Gon;Lee, Jin-Soo;Kim, Tong-Kwon;Ko, Kyung-Seok;Lee, Gyoo-Ho
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.878-883
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    • 2005
  • This paper describes the effect of acid rock drainage(ARD) produced from the cut slope on the slope structures. Acid rock drainage is originated from a rock quarry located in coal mine zone and mineralization belt of Chosen Supergroup and Ogcheon group, andesite with the pyrite, and acid sulfate soils of Tertiary in Korea. The cut slope, where acid rock drainage comes out, almost has been constructed by shotcrete and planting works. According to the field observation results, in most cases, the acid rock drainage has an adverse effect on slope structures. The shotcrete, anchors and rock bolts produced corrosive action, and bad germination and growth diseases of covering plants of the slope planting construction due to ARD.

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Paper Title : Speech Parameter Estimation and Enhancement Using the EM Algorithm (EM 알고리즘을 이용한 음성 파라미터 추정 및 향상)

  • Lee, Ki-Yong;Kang, Young-Tae;Lee, Byung-Gook
    • The Journal of the Acoustical Society of Korea
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    • v.13 no.2E
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    • pp.68-75
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    • 1994
  • In many applications of signal processing, we have to deal with densities which are highly non-Gaussian or which may have Gaussian shape in the middle but have potent deviations in the tails. To fight against these deviations, we consider a finite mixture distribution for the speech excitation. We utilize the EM algorithm for the estimation of speech parameters and their enhancement. Robust Kalman filtering is used in the enhancement process, and a detection/estimation technique is used for parameter estimation. Experimental results show that the proposed algorithm performs better in adverse SNR input conditions.

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A Study on the Characteristics of Blasting Vibration from Different Excavation Methods in Underground Mine (지하채굴공동에서 굴착방법에 따른 발파진동의 특성에 관한 연구)

  • Kang Choo-Won;Ryu Pog-Hyun
    • Explosives and Blasting
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    • v.24 no.1
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    • pp.1-8
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    • 2006
  • Recently, most of limestone quarries have been not mined by open-pit mining but by underground excavation to reduce environmental pollution. As a result, the size of underground galleries became bigger to maintain mass-production close to open-pit mining. However, the scale of pillars and galleries as well as the excavation methods may induce a few adverse problems for the stability of a mined gallery. In this study, the nomogram analysis and the prediction of rock damage zone induced by blasting were carried out. The testing conditions include concurrent blasting of two adjacent galleries, concurrent blasting of a transport drift and a inclined shaft, sequential blasting of two galleries, and separate blasting for each gallery. For each testing condition, blast vibration velocity was measured and analyzed. From the prediction formulas for blast vibration velocity derived in this study, the maximum depth of rock damage zone induced by blasting were also predicted.

Structure Evaluation for the Level Luffing Crane' Boom (레벨 러핑 크레인 붐에 대한 구조설계의 건전성 평가)

  • Kim, Min-Saeng;Lee, Jae-Chul;Jeong, Suk-Yong;Ahn, Sung-Hoon;Son, Jee-Won;Cho, Kwang-Je;Song, Chul-Ki;Park, Sil-Ryong;Bae, Tae-Han
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.6
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    • pp.526-532
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    • 2008
  • Structure evaluation for 70/15 $T{\times}105\;m$ LLC(Level Luffing Crane)'s boom was conducted by Finite Element Method. Boom modeled with beam element was fixed by luff rope and boom mount and was received loads from self weight, luff hoisting, traveling motion, slewing motion, and wind force, etc. These applied loads were calculated using various factors presented in the reference standards and were inputted in the analysis model after considering about the adverse conditions of LLC. In the research, deformation, stresses, buckling of boom were evaluated by ANSYS. Structural safety of boom was confirmed in the results of numerical analysis.

A Case Report of Patient with Meningioma of Brain Clinically Improved By Acupuncture Treatment(Dongshiqixue) (침치료(동씨기혈(董氏奇穴))로 임상증상이 호전된 뇌수막종 환자 1례)

  • Lee, Kang-Su;Moon, Woong-A;Lee, Jin-Hwa
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.9 no.1
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    • pp.47-52
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    • 2003
  • Acupuncture is a complementary medical treatment whose use in cancer patients has been recommended by the American Cancer Society (ACS) for the treatment of cancer and treatment-related symptoms. Pain, nausea, breathlessness, vasomotor symptoms and limb edema have all been found to respond to this treatment modality. This has become quite familiar to many Koreans not only for pain, but also for many other health problems, both in acute and chronic conditions. Actually, acupuncture is a therapeutic technique that is part of a larger system of traditional oriental medicine. There are several styles of acupuncture. We treated one 72-year-old female patient with Dongshiqixue Acupuncture Technique who had refused surgical operation for brain meningioma showing right hemiparesis, dysarthria, headache and dizziness. During the acupuncture treatment, there were no other adverse effects. After six day's treatment, she could ambulate and make usual life all by herself. On her brain magnetic resonence image follow-up, there was no interval change in meningioma. After discharged from our hospital, she has kept up her independent daily life as before. So it is suggested that some acupuncture treatment should be effect on brain meningioma clinically.

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Why Dynamic Security for the Internet of Things?

  • Hashemi, Seyyed Yasser;Aliee, Fereidoon Shams
    • Journal of Computing Science and Engineering
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    • v.12 no.1
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    • pp.12-23
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    • 2018
  • The Internet of Things (IoT) ecosystem potentially includes heterogeneous devices with different processing mechanisms as well as very complicated network and communication models. Thus, analysis of data associated with adverse conditions is much more complicated. Moreover, mobile things in the IoT lead to dynamic alteration of environments and developments of a dynamic and ultra-large-scale (ULS) environment. Also, IoT and the services provided by that are mostly based on devices with limited resources or things that may not be capable of hosting conventional controls. Finally, the dynamic and heterogeneous and ULS environment of the IoT will lead to the emergence of new security requirements. The conventional preventive and diagnostic security controls cannot sufficiently protect it against increasing complication of threats. The counteractions provided by these methods are mostly dependent on insufficient static data that cannot sufficiently protect systems against sophisticated and dynamically evolved attacks. Accordingly, this paper investigates the current security approaches employed in the IoT architectures. Moreover, we define the dynamic security based on dynamic event analysis, dynamic engineering of new security requirements, context awareness and adaptability, clarify the need for employment of new security mechanism, and delineate further works that need to be conducted to achieve a secure IoT.

A Study on the Establishment of Criteria for Safe Unberthing in Pohang by "PC-based DeskTop Ship Maneuvering Simulator for trainning purpose" (선박조종연습용 PC Desktop Simulator를 이용한 포항항 지반 기준설정에 관한 연구)

  • 허용범;윤점동
    • Journal of the Korean Institute of Navigation
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    • v.20 no.3
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    • pp.13-30
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    • 1996
  • It is general that large ships entering or leaving a port located in the East coast of Korean peninsular are often exposed athwart to swell while maneuvering in the vicinity of breakwater at harbor enterance or to prevailing wind inside the port in winter. Particulary, Many VLCCs laden with ore coal are calling at Pohang Port, on account of which it is likely that one of those VLCCs block the port if they were to run aground in fairway due to adverse circumstance of swell, prevailing winds or improper shiphandling. This accident may result in delay of delivery of raw material for Pohang Steel Mill which will bring about shortcomings of steel products for nationwide relevant industries causing national economic shock. Therefore, This study basically aims at establishment of certain criteria for safe unberthing of VLCC in this port to prevent such unexpected disaster because any VLLC is highly affected by external forces when in ballast condition. Computer simulations are unavoidable to fulfull this study successfuly and many simulations have been carried out repeatedly to find a model of safe unberthing under various unfavourable wind conditions. The "PC-based ship maneuvering simulator for training purpose" was used to perform numerous simulations at the least economic burden and to verify its availability that it can be used not only for training but also some other purposes. purposes.

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The Impact Analyses on the Downstream by the Existing Golf Course (골프장 유출수가 하류수계에 미치는 영향)

  • Lee, Byoung Ho;Kim, Seong Deuk;Cho, Hong Je;Cho, Tae Kyu
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.3
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    • pp.239-251
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    • 1992
  • There has been a great deal of controversy in the views on the impact of the pesticide pollution from the golf courses. The stream and reservoir associated with a existing golf course were investigated. The parameters include the ones related with eutrophication, heavy metals, pesticides. and aquatic ecological conditions. It was found that the impact on the aquatic ecosystem by the pollution from the golf course was not so serious. An aquatic ecological food chain was well established in the reservoir which belongs to the golf course. In contradiction to the general recognition, the livestock farming and agricultural farming gave much more adverse impacts on the stream than the golf course.

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Efficacy and safety of growth hormone treatment for children born small for gestational age

  • Hwang, Il Tae
    • Clinical and Experimental Pediatrics
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    • v.57 no.9
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    • pp.379-383
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    • 2014
  • Recombinant growth hormone (GH) is an effective treatment for short children who are born small for gestational age (SGA). Short children born SGA who fail to demonstrate catch-up growth by 2-4 years of age are candidates for GH treatment initiated to achieve catch-up growth to a normal height in early childhood, maintain a normal height gain throughout childhood, and achieve an adult height within the normal target range. GH treatment at a dose of $35-70{\mu}g/kg/day$ should be considered for those with very marked growth retardation, as these patients require rapid catch-up growth. Factors associated with response to GH treatment during the initial 2-3 years of therapy include age and height standard deviation scores at the start of therapy, midparental height, and GH dose. Adverse events due to GH treatment are no more common in the SGA population than in other conditions treated with GH. Early surveillance in growth clinics is strongly recommended for children born SGA who have not caught up. Although high dose of up to 0.067 mg/kg/day are relatively safe for short children with growth failure, clinicians need to remain aware of long-term mortality and morbidity after GH treatment.

An Integrated Watershed Environmental Assessment and Classification of the Mid-Nakdong River Region (낙동강 중류 지역의 통합적 유역환경평가 및 유형화)

  • Jung, Sung-Gwan;Park, Kyung-Hun
    • Journal of Environmental Impact Assessment
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    • v.13 no.3
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    • pp.137-151
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    • 2004
  • Many of today's environmental problems are regional in scope and their effects overlap and interact. The purpose of this paper is to developed a simple method for an integrated assessment of environmental conditions across the Mid-Nakdong River Region, by combining data on land use, impervious cover, roads, streams, riparian areas, forest patches, population, pollutant loadings, soil erosion and topography. A cluster analysis was used to identify groups of sub-watersheds with similar environmental characteristics. The mean value for each group was used to find watershed that may be more vulnerable to future environmental degradation. Watersheds in cluster I and II had high amount of forest, but the amount of riparian vegetation was low. Watersheds in cluster III, which located in the middle Geumho River and the main course of Nakdong River, had a greater proportion of their agriculture, a greater proportion of agriculture on steep slopes, and less forest adjacent to streams. Watersheds in cluster IV and V were in the most urbanized areas of the region. The principal adverse impacts for watersheds in this group were high scores for urban area, impervious cover, pollutant loadings, population density, forest fragmentation, and low amounts of forest and riparian forest cover. Notwithstanding the exploratory nature of cluster analysis, it appears to be a useful tool for grouping watersheds with similar environmental characteristics.