• Title/Summary/Keyword: Deterioration Factor

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Analysis of Microclimate and Conservation Environment of the Stone Buddha and Shrine in Unjusa Temple, Hwasun, Korea (화순 운주사 석조불감의 보존환경 및 미기상 분석)

  • Park, Sung-Mi;Lee, Chan-Hee;Lee, Myeong-Seong;Kim, Sa-Dug
    • Economic and Environmental Geology
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    • v.42 no.1
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    • pp.73-84
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    • 2009
  • The stone Buddha and Shrine of Unjusa temple (Korean Treasure No. 797) at Hwasun formed in Koryo Dynasty is unique style which faces each other the back parts of south and north within the stone Shrine. The stone Buddha and Shrine is highly evaluated in historical, artistic and academic respects. But, the stone properties have been exposed in the open system various aspects of degradations weathered for a long time without specific protective facilities. To inquire into relative deterioration and environmental factor, air temperature and relative humidity of the stone Buddha and Shrine were monitored for a year of the indoor and outdoor, respectively. As a result, the temperature shows increase and decrease according to the seasons in the tendency to clear. While the relative humidity is high to keep all four seasons. Highly relative humidity environment induces dew condensation on the interior of stone Buddha and Shrine. The dew condensation is recorded at the spring, summer and winter season. The summer season is double the total of spring and winter season. In the case of summer, dew condensation is long time continued due to high temperature and relative humidity that is kept by more than nearly 100%. There is progress towards chemical weathering throughout dissolve rock properties and alteration on the rock surface. In the case of winter, dew condensation is not kept for a long time as summer. In the winter, which showing a below zero may add physical weathering throughout moisture that happen by dew condensation to repeat freezing and thawing. Therefore, the reduction plan of the relative humidity effect on dew condensation should be prepared.

Use Impacts of Trail and Campsite on Natural Environments in Mt. Palgong Natural Park (팔공산자연공원에서의 등산로 및 야영장 이용이 자연환경에 미치는 영향)

  • 권태호
    • Journal of the Korean Institute of Landscape Architecture
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    • v.17 no.3
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    • pp.21-34
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    • 1990
  • Trail and campground deteriorations and their environmental changes of soil and vegetation were studied in Tonghwa -Sa district of Mt. Palgong Natural Park through 1988 into 1989. The results are summarized as follows : 1. The bare width of trail as one of the trail condition factor was significantly greater on the more heavily used trail. Deterioration types of trail which had higher frequency for a total of 45 observations were rock exposure(42%), trail deepening(40%) and root exposure(18%) in the high order. And also sound type on which the trail was not deteriorated at all amounted to 33% of all observations. 2. Ecological changes of soil and vegatation of trailsides were not found at a uniform tendency except that soil hardness was slightly decreased from trail edge to the forest, but they could be grouped by the type of user\`s behavior and site conditions. Use impacts on the natural environment of trailside in Mt. Palgong are still far from the severe harmulness. 3. Worse damages to compground condition were appeared in Bawi-gol than Susu-gol campsite. Types of mechanically damaged trees were tree with exposed root(63% ), scared tree(43% ), mutilated tree(30 % ) and felled tree in highly frequent order. And diameter increments of trees in campsites were oppressed by the campers. 4. Tree damage types and their frequencies could be basic as a means of which grasp the bounds of user's impacts. User's disturbance on campsite extended to the distance of 70∼90m from the core of campsite at Pawi-gol and 20∼30m at Susu-gol respectively. As the tolerant trees to use impact, Lespedeza maximowiczii, Rhus trichocarpa, Acer palmatum, Rubus crataegifolius and Celastrus orbiculatus were considered.

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The effect analysis of birefringence of plastic f$\heta$ Iens on the beam diameter (플라스틱 f$\heta$렌즈의 복굴절이 결상빔경에 미치는 영향분석)

  • 임천석
    • Korean Journal of Optics and Photonics
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    • v.11 no.2
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    • pp.73-79
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    • 2000
  • We measure a beam diameter of scan and sub-scan direction of LSD (Laser Scanning Urnt) which uses $fheta$ lens produced by injecLion molding method as a scanning lens. While the measured beam diameter in scan direction, which is $62muextrm{m}$ to $68\mu\textrm{m}$, shows similar size comparing to the design beam diameter, the sub-scan beam diameter shows sIzable beam diameter deviation as much as 37 11m ranging from $78\mu\textrm{m}$ to $115\mu\textrm{m}$. Injection molding lens has the surface figure error due to the shrinkage III the cooling time and the internal distortion (birefringence) due to the uneven cooling conditIOn so that these bring about wavefront aberration (i.e., the enlargement of beam size), and are eventually expre~sed as the deterioration of the pdnting image. In this paper. we first measure and analyze beam diameter, birefringence (polanzation ratio), and asphedcal figure error of mIens in order to know the principle cause of the beam diameter deviation in sub-scan directIOn. And Lhen. through the analysis of a designed depth of focus and a calculated field curvature (imaging position of the optical axis directIon) using the above figure elTor data, we know Lhat the birefringence IS the main factor of sizable beam diameter deVIation in sub-scan direction. ction.

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Preparation of Bismuth Telluride Thin Films using RF magnetron sputtering and Study on Their Thermoelectric Properties (RF 마그네트론 스퍼터링을 이용한 Bismuth Telluride 박막의 제조와 그 열전 특성 연구)

  • Kim, Dong-Ho;Lee, Gun-Hwan
    • Journal of the Korean Vacuum Society
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    • v.14 no.4
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    • pp.215-221
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    • 2005
  • Thermoelectric bismuth telluride thin films were prepared on $SiO_{2}$/Si substrate with co-sputtering of bismuth and tellurium targets. The effects of deposition temperature on surface morphology, crystallinity and electrical transport properties were investigated. Hexagonal crystallites were clearly visible at the surface of films deposited above $290 ^{\circ}C$. Change of dominant phase from rhombohedral $Bi_2Te_3$ to hexagonal BiTe was confirmed with X-ray diffraction analysis. The deviation from stoichiometric composition at high deposition temperature resulted in the change of structural and electrical characteristics. Seebeck coefficients of all samples have negative value, indicating the prepared $Bi_XTe_Y$ films are n-type thermoelectric. Optimum of Seebeck coefficient and power factor were obtained at the deposition temperature of $225 \^{circ}$C (about -55 $\mu$V/K and $3\times10^{-4}$ W/$k^{2}$m, respectively). Deterioration of thermoelectric properties at higher temperature.

Total Deformity Angular Ratio as a Risk Factor for Complications after Posterior Vertebral Column Resection Surgery

  • Lee, Byoung Hun;Hyun, Seung-Jae;Han, Sanghyun;Jeon, Se-Il;Kim, Ki-Jeong;Jahng, Tae-Ahn;Kim, Hyun-Jib
    • Journal of Korean Neurosurgical Society
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    • v.61 no.6
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    • pp.723-730
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    • 2018
  • Objective : The aim of the present study was to identify whether the deformity angular ratio (DAR) influences the occurrence of complications after posterior vertebral column resection (PVCR) and to establish the DAR cut-off value. Methods : Thirty-six consecutive patients undergoing PVCR from December 2010 to October 2016 were reviewed. The relationships between the total, sagittal, and coronal DAR and complications were assessed using receiver operator characteristics curves. The patients were divided into two groups according to a reference value based on the cut-off value of DAR. Demographic, surgical, radiological, and clinical outcomes were compared between the groups. Results : There were no significant differences in the patient demographic and surgical data between the groups. The cut-off values for the total DAR (T-DAR) and the sagittal DAR (S-DAR) were 20.2 and 16.4, respectively (p=0.018 and 0.010). Both values were significantly associated with complications (p=0.016 and 0.005). In the higher T-DAR group, total complications (12 vs. 21, p=0.042) and late-onset complications (3 vs. 9, p=0.036) were significantly correlated with the T-DAR. The number of patients experiencing complications (9 vs. 11, p=0.029) and the total number of complications (13 vs. 20, p=0.015) were significantly correlated with the S-DAR. Worsening intraoperative neurophysiologic monitoring was more frequent in the higher T-DAR group (2 vs. 4) than in the higher S-DAR group (3 vs. 3). There was no difference in neurological deterioration between the groups after surgery. Conclusion : Both the T-DAR and the S-DAR are risk factors for complications after PVCR. Those who had a T-DAR >20.2 or S-DAR >16.4 experienced a higher rate of complications after PVCR.

Deacidification Effect of Campbell Early Must through Carbonic-Maceration Treatment: Isolation and Properties of the Bacteria Associated with Deacidification (Carbonic Maceration처리에 의한 Campbell Early 발효액의 감산 효과: 감산 관련 미생물의 분리 및 특성)

  • Chang, Eun-Ha;Jeong, Seok-Tae;Jeong, Sung-Min;Lim, Byung-Sun;Noh, Jung-Ho;Park, Kyo-Sun;Park, Seo-Jun;Choi, Jong-Uck
    • Food Science and Preservation
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    • v.18 no.6
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    • pp.973-979
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    • 2011
  • The grape cultivar Campbell Early has high levels of malic acid as well as tartaric acid. The high concentration of total acid in the Campbell Early wine is a critical aspect of the wine's sensory characteristics. To prevent the deterioration of the wine's quality, which is caused by the strong sour taste derived from the raw material in wine making, the deacidification factor was investigated via carbonic maceration under different temperature conditions, especially in the presence or absence of malolactic bacteria. Based on the results of the presence test of the malolactic bacteria during carbonic-maceration treatment, Lactobacillus brevis, Lactobacillus plantarum, and Streptococcus thermophilus were characterized morphologically and were identified via biochemical tests and 16S-rRNA-gene-sequencing analysis. The isolated strains were found not to consume malic acid and to produce lactic acid. Moreover, these strains were consumed as soluble solids. The isolated strains are popularly known as lactic-acid bacteria and should have produced lactic acid from glucose. The Oenococcus oeni of the malolactic bacteria was not isolated. These results showed that the isolated strains are not deacidified during carbonic-maceration treatment.

Association of Hemoglobin Levels and Cognitive Function in Alzheimer's Disease and Mild Cognitive Impairment (알츠하이머병과 경도인지장애에서 헤모글로빈 농도와 인지기능과의 연관성)

  • Park, Joon Kyung;Lee, Kang Joon;Kim, Hyun
    • Korean Journal of Psychosomatic Medicine
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    • v.24 no.1
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    • pp.94-101
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    • 2016
  • Objectives : Anemia is a common problem in the management of elderly patients. Recent studies reported that anemia was associated with cognitive impairment and Alzheimer's disease. This study was aimed to analyze the differences of hemoglobin levels in Korean patients with Alzheimer's disease(AD) dementia, mild cognitive impairment(MCI), and healthy controls. Furthermore, the study also examined if any association between hemoglobin levels and cognitive functions existed. Methods : A total of 116 Korean elderly adults were participated in this study(mean age 74.67 years ; 60.3% female). The Korean version of the Mini-Mental State Examination(MMSE-K), Clinical Dementia Rating(CDR) and Global Deterioration Scale(GDS) were applied to all subjects. Hematological and related blood chemistry values were investigated. Results : We found that patients with AD dementia had significantly lower hemoglobin and hematocrit levels than MCI subjects and healthy control group. The hemoglobin levels showed a positive correlation with MMSE-K and negative correlation with CDR, GDS. Conclusions : Among Korean elderly, low hemoglobin level is associated with a cognitive impairment. This study indicates that AD is associated with anemia, and low hemoglobin levels may contribute to potentially useful clinical markers of AD. The risk factor for dementia needs to be confirmed by prospective longitudinal studies in a larger group of patients.

Quality Change of Packaged Pears in PLA Tray for Export due to Vibration Stress by Simulated Transport Environment (PLA 트레이 포장 수출용 배의 수송 모의환경 진동 스트레스에 의한 품질변화)

  • Choi, Dong-Soo;Son, Jae-Yong;Kim, Jin-Se;Kim, Yong-Hoon;Park, Chun-Wan;Hwang, Sung-Wook;Park, Jong-Min;Jung, Hyun-Mo
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.27 no.2
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    • pp.109-114
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    • 2021
  • The characteristics of vibrational stress (shock and vibration) during transport and the possibility of damage to the packaged pears by functional PLA tray were investigated. And this study was conducted to analyze how environmental conditions by simulated transport environment affect quality factors such as weight loss (%) and soluble solid content (SSC, %), and firmness (bioyield strength, kPa) of packaged pears by PLA tray and Expanded PET foam pad (Group 1), EPE cushion cup pad and net (Group 2) for exporting. Pears with or without vibration stress were stored for 30 days at low temperatures (5 ± 0.8℃, 80 ± 5% relative humidity). There was the statistically significant difference (p ≤ 0.05) between pears with and without vibration stress for weight loss, soluble solid content, and firmness (bioyield strength) after 30 days storage. Vibration stress accelerated pear quality deterioration during storage, resulting in increased weight loss, soluble solids content, and reduced hardness. The firmness (bioyield strength) and weight changes of pears with PLA trays were smaller than those of conventional packaging box systems. It was determined that the firmness of agricultural products was a quality factor closely related to the storage period and that PLA could be applied.

The Fate of Proximal Junctional Vertebral Fractures after Long-Segment Spinal Fixation : Are There Predictable Radiologic Characteristics for Revision surgery?

  • Jang, Hyun Jun;Park, Jeong Yoon;Kuh, Sung Uk;Chin, Dong Kyu;Kim, Keun Su;Cho, Yong Eun;Hahn, Bang Sang;Kim, Kyung Hyun
    • Journal of Korean Neurosurgical Society
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    • v.64 no.3
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    • pp.437-446
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    • 2021
  • Objective : To investigate the radiographic characteristics of the uppermost instrumented vertebrae (UIV) and UIV+1 compression fractures that are predictive of revision surgery following long-segment spinal fixation. Methods : A total 27 patients who presented newly developed compression fracture at UIV, UIV+1 after long segment spinal fixation (minimum 5 vertebral bodies, lowest instrumented vertebra of L5 or distal) were reviewed retrospectively. Patients were divided into two groups according to following management : revisional surgery (group A, n=13) and conservative care (group B, n=14). Pre- and postoperative images, and images taken shortly before and after the occurrence of fracture were evaluated for radiologic characteristics Results : Despite similar degrees of surgical correction of deformity, the fate of the two groups with proximal junctional compression fractures differed. Immediately after the fracture, the decrement of adjacent disc height in group A (32.3±7.6 mm to 23.7±8.4 mm, Δ=8.5±6.9 mm) was greater than group B (31.0±13.9 mm to 30.1±15.5 mm, Δ=0.9±2.9 mm, p=0.003). Pre-operative magnetic resonance imaging indicated that group A patients have a higher grade of disc degeneration adjacent to fractured vertebrae compared to group B (modified Pfirrmann grade, group A : 6.10±0.99, group B : 4.08±0.90, p=0.004). Binary logistic regression analysis indicated that decrement of disc height was the only associated risk factor for future revision surgery (odds ratio, 1.891; 95% confidence interval, 1.121-3.190; p=0.017). Conclusion : Proximal junctional vertebral compression fractures with greater early-stage decrement of adjacent disc height were associated with increased risk of future neurological deterioration and necessity of revision. The condition of adjacent disc degeneration should be considered regarding severity and revision rate of proximal junctional kyphosis/proximal junction failures.

Factors Influencing Driving ability and Its Measurements in Older Driver: A Systematic Review (고령자의 운전능력 영향요인 및 측정도구에 대한 체계적 문헌고찰)

  • Woo, Ye-Shin;Shin, Ga-In;Park, Sang-Mi;Park, Hae Yean
    • 한국노년학
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    • v.38 no.1
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    • pp.225-241
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    • 2018
  • Self-driving is meaningful activity for older persons because it enlarges the range of activity and provides opportunities for social participation. Driving is a complex activity that requires integration of physical, cognitive and sensory functions and is influenced by human and psychological factors. Age related functional deterioration affects the driving ability of older drivers. The purpose of this study is to investigate the factors affecting the risk of accidents and driving cessation of elderly drivers through systematic literature review. MEDLINE, EMBASE, Cochrane Library, KoreaMed, Pubmed were used for searching articles published from 2007 to 2017. 'aged', 'aging', 'automobile driving', 'age factors' were used as search terms and 18 articles were finally selected for analysis among 1,458 articles. In result of the study, the most significant effect showed in the physical domain, the driving habit and the performance function. The most frequent used tools evaluated driving habit and the cognitive function. In demographic characteristics, there was a correlation with the driving discontinue according to sex and age. This study emphasizes the necessity of preparing measures for safety driving with elderly. In addition, it suggests the necessity of systematically services such as individual education programs based on various driving cessation related factors of the elderly.