• Title/Summary/Keyword: sample disturbance

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Cervical Spondylotic Myelopathy due to the Ochronotic Arthropathy of the Cervical Spine

  • Li, Nan;Tian, Wei;Yuan, Qiang;He, Da
    • Journal of Korean Neurosurgical Society
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    • v.59 no.1
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    • pp.65-68
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    • 2016
  • Ochronosis is a musculoskeletal manifestation of alkaptonuria, a rare hereditary metabolic disorder occurs due to the absence of homogentisic acid oxidase and leading to various systemic abnormalities related to deposition of homogentisic acid pigmentation (ochronotic pigmentation). The present case reports the clinical features, radiographic findings, treatments and results of a cervical spondylotic myelopathy woman patient due to the ochronotic arthropathy of the cervical spine. The patient aged 62 years was presented with gait disturbance and hand clumsiness. Physical examination, X-rays, computed tomography and lab results of the urine sample confirmed the presence of ochronosis with the involvement of the cervical spine. The patient underwent a modified cervical laminoplasty due to multi-segment spinal cord compression. The postoperative follow-up showed a good functional outcome with patient satisfaction. The present study concludes the conditions and important diagnostic and surgical aspects of a patient. It is necessary to identify the condition clinically and if cord compression is observed, appropriate surgical interventions needs to be instituted.

Verification and Analysis of Characteristics of Mechanical Pulsation for Combustion Stability Study in a Model Chamber (모형 연소기의 연소 불안정성 연구용 섭동 장치의 기능 검증 및 분석)

  • Min, Yong-Ho;Sohn, Chae-Hoon
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2012.05a
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    • pp.28-30
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    • 2012
  • A mechanical pulsator is manufactured for study of combustion instabilities in a model chamber with impinging-jet injectors. Artificial disturbance is generated by the device and thereby, artificial instability can be examined experimentally. A sample F(fuel)-O(dxidizer)-O-F impinging-jet injector is adopted for the test. The model chamber was designed based on the methodologies proposed in the previous work regarding geometrical dimensions and operating conditions. Pressure fluctuation data, which is obtained from the dynamic pressure transducers installed in combustion chamber, is analyzed.

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Antifouling technology and sea trial verification according to surface treatment (표면 처리를 통한 친환경 방오 기술 및 실해역 평가 연구)

  • Han, Deok-Hyun;Koh, Hyeok-Jun;Jung, Hang-Chul
    • Journal of the Korean institute of surface engineering
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    • v.55 no.6
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    • pp.425-432
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    • 2022
  • Antifouling paints that inhibit the attachment and contamination of marine organisms mainly use TBT compounds, but because of their toxic components, they cause ecosystem disturbance and environmental destruction problems, so It is necessary to research eco-friendly antifouling paints that are easy to maintain and effective antifouling technologies. In this study, physical surface treatment of silane coating and chemical antifouling technology were applied to the metal surface to secure the stability of the surface of the marine structure and inhibit the attachment and growth of marine organisms. Adhesion of marine organisms was evaluated according to the coating conditions through surface evaluation of the charged material for 15 months in the waters of the west coast of Korea. In accordance with ASTM D6990-05, antifouling properties fouling rates (FR) and physical degradation rates(PDR) were evaluated through visual inspection of the evaluation specimens. As a result of evaluating the antifouling performance of the coated surface, it was confirmed that the antifouling performance was maintained at the 50% level even after 15 months in the sample subjected to physical processing and silane coating.

Research Trends of Korean Medicine Treatments for Postoperative Sleep Improvement: Focusing on Herbal Medicine, Acupuncture, and Moxibustion (수술 후 환자의 수면 개선에 대한 한의치료 임상연구 동향 -한약, 침, 뜸 치료를 중심으로-)

  • Jun-Hee, Cho;Bo-Kyung, Kim;Jung-Hwa, Lim
    • Journal of Oriental Neuropsychiatry
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    • v.33 no.4
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    • pp.425-451
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    • 2022
  • Objectives: To review trends of clinical trials on Korean medicine treatments for postoperative sleep improvement. Methods: We searched randomized controlled trials (RCTs) on Korean medicine treatments for postoperative sleep improvement from ten domestic and foreign databases. Sample sizes, diseases, types of operation, diagnosis tools, pattern identification, interventions, outcome measurements, and main results of included studies were extracted and analyzed. Results: A total of 20 RCTs were selected. Most studies were published in China. The most common target disease was cancer, followed by cardiovascular disease. Most studies lacked detailed description regarding participants such as onset, duration of sleep disturbance, and preoperative sleep issues. Herbal medicine was the most frequently used in 12 studies. The most commonly used prescription was Suanzaoren decoction. The effectiveness of Korean medicine treatment on improving postoperative sleep was found to be significant in most studies. Conclusions: Korean medicine treatments might be effective in postoperative sleep improvement. However, the quality of included studies was low. Therefore, further well-designed research studies are needed to provide high quality clinical evidence on Korean medicine treatments for postoperative sleep improvement.

Engineering characterization of intermediate geomaterials - A review

  • T. Ashok Kumar;Ramanandan Saseendran;V. Sundaravel
    • Geomechanics and Engineering
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    • v.33 no.5
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    • pp.453-462
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    • 2023
  • Intermediate Geomaterials (IGMs) are natural formation materials that exhibit the engineering behavior (strength and compressibility) between soils and rocks. The engineering behavior of such material is highly unpredictable as the IGMs are stiffer than soils and weaker/softer than rocks. Further, the characterization of such material needs exposure to both soil and rock mechanics. In most conventional designs of geotechnical structures, the engineering properties of the IGMs are either aligned with soils or rocks, and this assumption may end up either in an over-conservative design or under-conservative design. Hence, many researchers have attempted to evaluate its actual engineering properties through laboratory tests. However, the test results are partially reliable due to the poor core recovery of IGMs and the possible sample disturbance. Subsequently, in-situ tests have been used in recent years to evaluate the engineering properties of IGMs. However, the respective in-situ test finds its limitations while exploring IGMs with different geological formations at deeper depths with the constraints of sampling. Standard Penetration Test (SPT) is the strength-based index test that is often used to explore IGMs. Moreover, it was also observed that the coefficient of variation of the design parameters (which represents the uncertainties in the design parameters) of IGMs is relatively high, and also the studies on the probabilistic characterization of IGMs are limited compared with soils and rocks. With this perspective, the present article reviews the laboratory and in-situ tests used to characterize the IGMs and explores the shear strength variation based on their geological origin.

A Cross-Validation of the Korean Version of the Revised Memory and Behavioral Problems Checklist(K-RMBPC): Exploratory and Confirmatory Analyses ("한국형 기억 및 행동문제 개정점검표(Korean Version of the Revised Memory and Behavioral Problems Checklist: K-RMBPC)"의 타당화를 위한 탐색적 연구)

  • Lee, Min-Hong;Yoon, Eun-Kyung
    • Korean Journal of Social Welfare
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    • v.59 no.2
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    • pp.65-88
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    • 2007
  • This study evaluates psychometric properties of the Revised Memory and Behavioral Problems Checklist(RMBPC) in Korean version. The sample includes 387 South Korean family caregivers who provide the majority of day to day tasks and emotional care for their older family members with physical and/or cognitive disabilities. The psychometric properties of the RMBPC are verified by item analysis, exploratory factor analysis(EFA) & confirmatory factor analysis(CFA). For cross-validity, the randomly divided two samples are used: one sample for EFA(n=193, 387/2) and the other sample for CFA(n=194, 387/2). The internal consistency of the K-RMBPC is excellent, and the convergent and criterion-related validity of the K-RMBPC with related variables is empirically confirmed. An EFA based on the Principal Component Analysis(PCA) method with varimax rotation explains 65.85% of variance accounted for by the three factors. A CFA also verifies that the model fit was acceptable. The shorter Korean version of the RMBPC is found reliable and valid. The translated checklist would be very useful for clinical and research settings by (a) focusing on observable, conceptually relevant, potentially modifiable behaviors and (b) using objective criteria within a self-administered framework, to enable clinicians and researchers to pinpoint areas of disturbance and target intervention goals for patients and caregivers in a cost-effective manner.

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Short Sleep Duration and Its Correlates among Cancer Survivors in Korea: the Korea National Health and Nutrition Examination Surveys

  • Yoon, Hyung-Suk;Yang, Jae Jeong;Song, Minkyo;Lee, Hwi-Won;Lee, Yunhee;Lee, Kyoung-Mu;Lee, Sang-Ah;Lee, Jong-koo;Kang, Daehee
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.11
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    • pp.4705-4710
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    • 2015
  • Background: Though a large proportion of cancer survivors are assumed to be commonly affected by sleep disturbance, few studies have focused on short sleep problems and its correlates among Korean cancer survivors. The purpose of this study was to evaluate the prevalence of short sleep in adult cancer survivors from a nationwide population-based sample and to identify risk factors for short sleep duration. Materials and Methods: Based on the fourth and fifth Korea National Health and Nutrition Examination Surveys (2007-2012), 1,045 cancer survivors and 33,929 non-cancer controls were analyzed. The prevalence of short sleep was compared between these two groups. Associations between short sleep and its correlates were evaluated using multiple logistic regression among cancer survivors: odds ratios (ORs) and 95% confidence intervals (95%CIs) were estimated after adjusting for sociodemographic factors, lifestyle factors, psychological conditions, and cancer-related factors. Results: About 8.1% of cancer survivors slept for less than 5 hours per day (6.2% men and 9.3% women), whereas this was the case for only 3.7% of non-cancer controls. Cancer survivors who had the lowest household income level showed a significantly higher likelihood for short sleep (adjusted OR 2.82, 95%CI 1.06-7.54). Self-reported poor health and depressive symptoms were found to be associated with significantly increased likelihood for short sleep in cancer survivors (adjusted OR 3.60, 95%CI 1.40-9.26 and adjusted OR 2.00, 95%CI 1.17-3.42). Gastric cancer survivors had a 3.97-fold increased risk for short sleep (95%CI 1.60-9.90). Conclusions: The prevalence of short sleep occurs at a high rate among the Korean cancer survivors, which may indicate a poorer quality of life and a higher risk of future complications in survivorship. Targeted interventions that can assist cancer survivors to cope with sleep disturbances as well as ensuring psychological stability are warranted to reduce the latent disease burden.

Suggestion of Modified Compression Index for secondary consolidation using by Nonlinear Elasto Viscoplastic Models (비선형 점탄소성 모델을 이용한 2차압밀이 포함된 수정압축지수개발)

  • Choi, Bu-Sung;Im, Jong-Chul;Kwon, Jung-Keun
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.1115-1123
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    • 2008
  • When constructing projects such as road embankments, bridge approaches, dikes or buildings on soft, compressible soils, significant settlements may occur due to the consolidation of these soils under the superimposed loads. The compressibility of the soil skeleton of a soft clay is influenced by such factors as structure and fabric, stress path, temperature and loading rate. Although it is possible to determine appropriate relations and the corresponding material parameters in the laboratory, it is well known that sample disturbance due to stress release, temperature change and moisture content change can have a profound effect on the compressibility of a clay. The early research of Tezaghi and Casagrande has had a lasting influence on our interpretation of consolidation data. The 24 hour, incremental load, oedometer test has become, more or less, the standard procedure for determining the one-dimensional, stress-strain behavior of clays. An important notion relates to the interpretation of the data is the ore-consolidation pressure ${\sigma}_p$, which is located approximately at the break in the slope on the curve. From a practical point of view, this pressure is usually viewed as corresponding to the maximum past effective stress supported by the soil. Researchers have shown, however, that the value of ${\sigma}_p$ depends on the test procedure. furthermore, owing to sampling disturbance, the results of the laboratory consolidation test must be corrected to better capture the in-situ compressibility characteristics. The corrections apply, strictly speaking, to soils where the relation between strain and effective stress is time independent. An important assumption in Terzaghi's one-dimensional theory of consolidation is that the soil skeleton behaves elastically. On the other hand, Buisman recognized that creep deformations in settlement analysis can be important. this has led to extensions to Terzaghi's theory by various investigators, including the applicant and coworkers. The main object of this study is to suggestion the modified compression index value to predict settlements by back calculating the $C_c$ from different numerical models, which are giving best prediction settlements for multi layers including very thick soft clay.

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Measurement of Wax Appearance Temperature Using Image Processing (영상 처리기법을 이용한 오일의 왁스생성온도 측정)

  • Hwang, Soon-Hye;Kang, Pan-Sang;Lim, Jong-Se
    • Journal of Energy Engineering
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    • v.25 no.1
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    • pp.1-8
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    • 2016
  • When the oil is produced in the low temperature environment, wax can be accumulated in petroleum production system(pipeline, riser) and causes problems such as pipeline stucking, disturbance of the oil production. These problems can be lead to time-consuming and economic losses for flow assurance. For prediction and mitigation of wax deposition, it is necessary to measure the Wax Appearance Temperature(WAT) which is a temperature when the wax crystals start to be formed. WAT standard measurement method of transparent oil has to determine the cloud point of sample to the naked eye and cannot be applied to continuous change of the temperature. In this study, wax behavior of transparent oil samples are recorded depending on temperature using Visualized WAT Measurement System. Also, WATs of transparent oil samples are measured by image processing and compared with the result of the standard method.

A Comparative Study on the Relationship between Tree Form and Volume in Stands of Pinus koraiensis and Larix leptolepis (잣나무의 낙엽송림(落葉松林)에 있어서 수형(樹型)과 재적간(材積間)의 관계(關係) 비교(比較))

  • Kim, Ji Hong;Lee, Chong Koo
    • Journal of Korean Society of Forest Science
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    • v.74 no.1
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    • pp.82-87
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    • 1986
  • Noticed that large number of the Korean white pine (Pinus koraiensis S. et Z.) has lost its typical excurrent tree from by removal of apical shoot in the process of cone harvesting, the investigation and analysis for the species were made on the basis of the relationship among DBH, total height, merchantable height, and merchantable volume, compared with normally grown Japanese larch (Larix leptolepis Gordon). One hundred sample trees for each species were selected in the same aged stands for the study. Results have indicated that the pine has shown abnormal height growth pattern mainly by the disturbance of external artificial force. The pine's forked and/or crooked stems by the reason lave led the result of less merchantable volume in the same DBH classes. Consequently, the pine would have undesirable tree form in terms of timber production, unless free from apical shoot disturbances. Considered to the merit of the Korean white pine that can produce timber and pine nuts, management alternatives for the pine stand were suggested to achieve maximum rate of return for the silvicultural investment.

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