Free Vibration of Layered Circular Cylindrical Shells of Variable Thickness Using Spline Function Approximation

Free vibration of layered circular cylindrical shells of variable thickness is studied using spline function approximation by applying a point collocation method. The shell is made up of uniform layers of isotropic or specially orthotropic materials. The equations of motions in longitudinal, circumferential and transverse displacement components, are derived using extension of Love's first approximation theory. The coupled differential equations are solved using Bickley-type splines of suitable order, which are cubic and quintic, by applying the point collocation method. This results in the generalized eigenvalue problem by combining the suitable boundary conditions. The effect of frequency parameters and the corresponding mode shapes of vibration are studied with different thickness variation coefficients, and other parameters. The thickness variations are assumed to be linear, exponential, and sinusoidal along the axial direction. The results are given graphically and comparisons are made with those results obtained using finite element method

Sustainable Conservation of a Difficult Heritage in South Korea: Mapping the Conservation Resources of Sorok-do Island, Hansen’s Disease Site

South Korea’s Sorok-do island bears witness to the 100-year history of the Sorok-do hospital and the village for Hansen’s disease (leprosy) patients. All the facilities of Sorok-do were established by the Japanese imperial authorities, and the collective memories of social isolation and discrimination against Hansen’s disease patients were deeply embedded in this island during the colonial and post-colonial periods. Despite changing perceptions toward the conservation of the island’s history since the 1990s, the island’s deep collective memory remains at risk due to the increasing number of incoming settlers and the shrinking number of Hansen’s disease patients since the opening of the Sorok Bridge in 2009. Taking into consideration the historical lack of critical engagement with difficult heritage conservation in South Korea, this paper introduces a novel approach to sustainable conservation, using as a case study the Sorok-do island. We collected data using archival research, participant observation and semi-structured in-depth interviews, and analyzed them by using a position-mapping method. This paper examines the island’s multifaceted, shifting processes within its history, urban structure, and changing social meanings, and offers a new set of criteria for long-term strategies that will ensure both tangible and intangible types of conservation resources.</jats:p

Bayesian Parameter Estimation Of Modified Bartlett-Lewis Rectangular Pulse (MBLRP) Poisson Cluster Model

Stochastic rainfall generators or stochastic simulation have been widely employed to generate synthetic rainfall sequences which can be used in hydrologic models as inputs. The calibration of Poisson cluster stochastic rainfall generator (e.g. Modified Bartlett-Lewis Rectangular Pulse, MBLRP) is seriously affected by local minima that is usually estimated from the local optimization algorithm. In this regard, global optimization techniques such as particle swarm optimization and shuffled complex evolution algorithm have been proposed to better estimate the parameters. Although the global search algorithm is designed to avoid the local minima, reliable parameter estimation of MBLRP model is not always feasible especially in a limited parameter space. In addition, uncertainty associated with parameters in the MBLRP rainfall generator has not been properly addressed yet. In this sense, this study aims to develop and test a Hierarchical Bayesian Model (HBM) based parameter estimation method for the MBLRP rainfall generator that allow us to derive the posterior distribution of the model parameters. Furthermore, this study investigates the choice of the object function in the calibration process within the Hierarchical Bayesian framework. The proposed models are tested to ensure model performance throughout the rainfall networks of more than 50 rain gauges in South Korea. It was found that the HBM based MBLRP model showed better performance in terms of reproducing rainfall statistic and underlying distribution of hourly rainfall serie

A Factor Analysis of Urban Railway Casualty Accidents and Establishment of Preventive Response Systems

AbstractSince the commencement of urban railways in 1974 and KTX service in 2014, the use of railways has been steadily increasing. The number of people using rail transportation has been steadily rising. As a result, this has also led to an increase in the number of passenger-related accidents that are occurring within railway stations. In an effort to prevent such accidents, much of the rail operation system is now automated. Nevertheless, the potential risks of railway accidents are very much present today. This study has utilized the railway accident databases of rail operators to allow for analysis of different types of railway accidents, age of accident victims, gender of accident victims, pedestrian facilities involved in accidents, passengers involved in accidents, and underlying causes of rail accidents. Based on these statistics and analyses, this paper proposes the development of a railway safety education program and the establishment of railway safety education centers as a means of preventing railway accidents

Quantitative Screening of Cervical Cancers for Low-Resource Settings: Pilot Study of Smartphone-Based Endoscopic Visual Inspection After Acetic Acid Using Machine Learning Techniques

Background: Approximately 90% of global cervical cancer (CC) is mostly found in low- and middle-income countries. In most cases, CC can be detected early through routine screening programs, including a cytology-based test. However, it is logistically difficult to offer this program in low-resource settings due to limited resources and infrastructure, and few trained experts. A visual inspection following the application of acetic acid (VIA) has been widely promoted and is routinely recommended as a viable form of CC screening in resource-constrained countries. Digital images of the cervix have been acquired during VIA procedure with better quality assurance and visualization, leading to higher diagnostic accuracy and reduction of the variability of detection rate. However, a colposcope is bulky, expensive, electricity-dependent, and needs routine maintenance, and to confirm the grade of abnormality through its images, a specialist must be present. Recently, smartphone-based imaging systems have made a significant impact on the practice of medicine by offering a cost-effective, rapid, and noninvasive method of evaluation. Furthermore, computer-aided analyses, including image processing-based methods and machine learning techniques, have also shown great potential for a high impact on medicinal evaluations

Anti-proliferative effects of Bifidobacterium adolescentis SPM0212 extract on human colon cancer cell lines

<p>Abstract</p> <p>Background</p> <p>Lactic acid bacteria (LAB) are beneficial probiotic organisms that contribute to improved nutrition, microbial balance, and immuno-enhancement of the intestinal tract, as well as anti-tumor activity. The aim of the present work was to study the growth inhibition of tumor cells by butanol extract of <it>Bifidobacterium adolescentis </it>isolated from healthy young Koreans.</p> <p>Methods</p> <p>The anti-proliferative activity of <it>B. adolescentis </it>isolates was assessed by XTT assays on three human colon cancer cell lines (Caco-2, HT-29, and SW480). The effects of <it>B. adolescentis </it>SPM0212 butanol extract on tumor necrosis factor-α (TNF-α) and nitric oxide (NO) production were tested using the murine macrophage RAW 264.7 cell line.</p> <p>Results</p> <p>The butanol extract of <it>B. adolescentis </it>SPM0212 dose-dependently inhibited the growth of Caco-2, HT-29, and SW480 cells by 70%, 30%, and 40%, respectively, at 200 μg/mL. Additionally, the butanol extract of <it>B. adolescentis </it>SPM0212 induced macrophage activation and significantly increased the production of TNF-α and NO, which regulate immune modulation and are cytotoxic to tumor cells.</p> <p>Conclusion</p> <p>The butanol extract of <it>B. adolescentis </it>SPM0212 increased activity of the host immune system and may improve human health by helping to prevent colon cancer as a biological response modifier.</p

Inhaled corticosteroid use and risks of lung cancer and laryngeal cancer

SummaryBackgroundChronic inflammation has been implicated in the pathogenesis of several cancers, including lung and laryngeal cancer. The objective of the study is to elucidate the association between ICS use and diagnosis of lung and laryngeal cancer.MethodsA nested case–control study based on the Korean national claims database included new adult users of inhaled medications between January 1, 2007, and December 31, 2010. Patients diagnosed with lung cancer or laryngeal cancer after enrollment were identified as cases and up to five control individuals matched for age, sex, diagnosis of asthma or COPD, Charlson Comorbidity Index scores, number of health care visits, and initiation date were selected.ResultsFrom the 792,687 eligible cohort, 9177 individuals diagnosed with lung cancer were matched with 37,048 controls. Additionally, 408 laryngeal cancer patients and 1651 controls were matched. ICS use was associated with a decreased rate of lung cancer diagnosis [adjusted odds ratio (aOR), 0.79; 95% confidence interval (CI), 0.69–0.90]. The inverse association between ICS use and lung cancer risk was dose dependent (P < 0.0001 for the trend). However, no reduction in the risk of laryngeal cancer among ICS users was identified (aOR, 1.06; 95% CI, 0.62–1.18).ConclusionThe use of ICS is associated with a reduced risk of lung cancer but not of laryngeal cancer

Cinnamaldehyde enhances in vitro parameters of immunity and reduces in vivo infection against avian coccidiosis

The effects of cinnamaldehyde (CINN) on in vitro parameters of immunity and in vivo protection against avian coccidiosis were evaluated. In vitro stimulation of chicken spleen lymphocytes with CINN (25-400ng/ml) induced greater cell proliferation compared with the medium control (P<0·001). CINN activated cultured macrophages to produce higher levels of NO at 1·2-5·0μg/ml (P<0·001), inhibited the growth of chicken tumour cells at 0·6-2·5μg/ml (P<0·001) and reduced the viability of Eimeria tenella parasites at 10 and 100μg/ml (P<0·05 and P<0·001, respectively), compared with media controls. In chickens fed a diet supplemented with CINN at 14·4mg/kg, the levels of IL-1β, IL-6, IL-15 and interferon-γ transcripts in intestinal lymphocytes were 2- to 47-fold higher (P<0·001) compared with chickens given a non-supplemented diet. To determine the effect of CINN diets on avian coccidiosis, chickens were fed diets supplemented with CINN at 14·4mg/kg (E. maxima or E. tenella) or 125mg/kg (E. acervulina) from hatch for 24d, and orally infected with 2·0×104 sporulated oocysts at age 14d. CINN-fed chickens showed 16·5 and 41·6% increased body-weight gains between 0-9d post-infection (DPI) with E. acervulina or E. maxima, reduced E. acervulina oocyst shedding between 5-9 DPI and increased E. tenella-stimulated parasite antibody responses at 9 DPI compared with control