A Study on PF–IFF-Based Diagnosis Model of Plant Equipment Failure

There are two types of maintenance policies for equipment: breakdown maintenance and preventive maintenance. In the case of applying preventive maintenance, the maintenance is carried out based on time or the condition of the equipment. However, with the development of Information and Communications Technologies (ICT) and the Internet of Things (IoT) technology, the data collected from equipment has rapidly increased and the use of Condition-Based Maintenance (CBM) to perform appropriate maintenance based on the condition of the equipment is increasing. In this study, based on gathered sensor data, we introduce an approach to diagnosing the condition of the equipment by extracting specific data features related to the types of failures that occur with equipment. To this end, we used the K-means clustering method, support vector machine (SVM) classifier, and Pattern Frequency–Inverse Failure mode Frequency (PF–IFF) method with the Term Frequency–Inverse Document Frequency (TF–IDF) method. As a case study, we applied the proposed approach to a centrifugal pump and carried out computational experiments for assessing the performance and validity of the proposed approach.

Increasing spring dust storms in the future over the Taklimakan Desert, Northwest China: implications from changes in circulation pattern frequency in CMIP6

Dust storms over the Taklimakan Desert (TD), Northwest China, not only influence human health but also affect regional climate through direct effects of dust aerosols on solar and longwave radiation. The Coupled Model Intercomparisons Project Phase 5 (CMIP5) models project a decrease in dust storms because of a decrease in dust emissions over the TD in the future under warming scenarios. However, inaccurate simulations of dust emissions cause the CMIP5 models to simulate dust storms poorly. Here we analyzed typical circulation patterns that initiate dust storms over the TD and examined changes in the frequency of typical circulation patterns derived from the CMIP6 models in an extreme warming scenario. The results show that there will be an increase in typical circulation pattern frequency in the latter half of the 21st century compared with 1958-2014, implying an increase in dust storms over the TD in the future under the extreme warming scenario. The increase in dust storms over the TD may be related to an increase in synoptic activities in the future from the Middle Asia to the TD, which is caused by a southern movement of subtropical westerly jet stream under the extreme warming scenario.

Transient Vestibular Symptoms Preceding Posterior Circulation Stroke

Background and Purpose: The recognition of clinical features of transient vestibular symptoms (TVSs) preceding posterior circulation stroke (PCOS) would be informative to discriminate dizziness/vertigo due to vertebrobasilar transient ischemic attack from the acute transient vestibular syndrome. We sought to determine the prevalence and characteristics of TVSs preceding PCOS. Methods: We performed a prospective multicenter observational study that had recruited 447 patients with PCOS from referral-based 4 university hospitals in Korea. We investigated the timing, pattern, frequency, duration, and accompanying neurological symptoms of TVSs during the 3 months preceding PCOS. Results: The prevalence of TVSs preceding PCOS was 12% (55/447) during the previous 3 months. The TVSs preceding PCOS occurred within 1 week (33%), between 1 week and 1 month (16%), or between 1 and 3 months (51%). The TVSs were mostly dizziness/vertigo with (36%) or without (60%) imbalance, while the remaining 4% had an isolated imbalance. The dizziness/vertigo was spinning in 38% and was aggravated during head position in 45%. The duration of TVSs was mostly a few seconds (55%) or minutes (38%). Approximately 72% of the patients with PCOS had TVSs 1 to 5 times, while 16% had >10 times. Accompanying neurological symptoms, including headache, tinnitus, limb weakness, sensory change, dysarthria, visual field defect, and diplopia, were reported in 11%. Conclusions: Preceding TVSs can occur in 12% of PCOS during the previous 3 months. Isolated dizziness/vertigo of unknown cause needs to be considered as a vertebrobasilar transient ischemic attack symptom, especially in patients with vascular risk factors. The characteristics of isolated vestibular symptom in vertebrobasilar transient ischemic attacks is highly variable and atypical compared with other transient ischemic symptoms.

Review of urological cancers in Damaturu, Nigeria

Background: Urological cancers (UC) remain a major global burden and a significant cause of high morbidity and mortality. In other to plan and tackle this burden, there is need to audit the pattern of these malignancies in our locality which is currently lacking. Hence, the objectives of our study were to describe the histological pattern, frequency and demographic characteristics of urological cancers seen in Damaturu.Methods: The reports of all the urological specimens that were histologically diagnosed as malignant between November 2017 to October 2019 in the histopathology department of Yobe state university teaching hospital, were analyzed. The department keeps newly established cancer registry for the state.Results: Fifty-five UC were diagnosed, with male to female ratio of 13.8:1. These UC constitute 34.1% of the 161 urological specimens assessed and 26.4% of all types of medical cancers diagnosed in the period of study. Prostate cancer dominates the UC (41; 73.8%), followed by bladder cancers (11; 19.8%) and the remaining kidney, penis and testicular cancers (1; 1.8%) each.Conclusions: Urological cancers are very common in our region, particularly prostate cancers in which majority were poorly differentiated. This report though analyzed few cancers, the proportion of UC is high. Urothelial cancer of the bladder is now more frequent than squamous cell carcinoma. This study can serve as basis for future epidemiologic studies targeting at the risk factors, awareness and prevention of UC.

Density and characteristics of Green mussels (Perna viridis) in Percut Sei Tuan coastal, North Sumatra, Indonesia

Percut Sei Tuan is a coastal area on the east coast of North Sumatra which has a lot of natural resource potential, one of them which is green mussels (Perna viridis). Green mussels have many benefits, namely for consumption, cultivation and bioindicator. This study aimed to determine the density, habitat location, growth pattern, frequency distribution of green mussels, physical-chemical parameters of water, a substrate of the bottom waters, and the relationship of green clams density to water and substrate parameters. The study was conducted in July-September 2020. Data analysis included density, the relationship of total length and weight of green mussels, the frequency distribution of shell lengths, and Principal Component Analysis (PCA). The results showed that the density of green mussels at stations I, II, and III were 352 ind/m2, 3 ind/m2, and 1 ind/m2, respectively. The relationship between the length and weight of green shells shows that the growth was negative allometric. The water condition, seen from the physical, chemical, and substrate parameters, was still suitable for P. viridis. Water and substrate parameters that were positively related to the density of green mussels were water temperature, nitrate, phosphate, C-organic, percentage of silt and clay. Parameters that were negatively related were salinity, pH, and percentage of sand in the bottom substrate. The present study suggested that Station I was an appropriate area for the growth and reproduction of green mussels.

THE TIPLING RIVER FLOW ANALYSIS TO ASSESS MICRO HYDRO POWER AND DIVERSION BASED IRRIGATION POTENTIAL

Micro hydropower projects and diversion based irrigation projects are dependent on the amount of water flowing in the river of concern. Analyses of historical River Flow information are crucial to understand its pattern, frequency and predictability. Statistical analysis is the basis for a better scientific comprehension of the river flow system. Based on this information designing of such projects as well as making management plans for any future eventualities are possible. In this paper historical discharge information for a period of 19 years is collected and analyzed. Based on the water level and volume of discharge information of the river for the year 1995, various stage discharge rating curves are prepared. The best fitted curve is used for the estimation of the discharge for the remaining years where only the stage information is available. Daily discharge hydrographs for 19 years is prepared along with annual discharge computation for each of the 19 years of observation period. Preparation of flow duration curve helped to understand what is to be expected minimum from the river and what could be the most risky situation for a river project in this river and make necessary allowances for designing such project. Finally seasonal and monthly time series models are prepared so that the future discharge could be scientifically forecasted for predicting the future of such projects.

Acquisition of broken plural patterns by Jordanian children

This study examines the acquisition of broken plural (BP) patterns generated by child speakers of Jordanian Arabic (JA). Data were collected from 20 Jordanian children via an experimental production test. Children were given pictures of a set of singular entities depicting nouns and pictures containing their plural counterparts, and they were asked to say the names of the items in the pictures in an attempt to provide their corresponding plural forms. The results reveal that the acquisition of correct BP patterns appears critical for children. The feminine sound plural (FSP) was employed as the default pattern by children and thus is acquired before the BP, with the acquired patterns mainly shaped by productivity, predictability (but not familiarity) and overgeneralization (morphological, phonological, and semantic). Based on the oral speech corpus produced by adult JA speakers, published in Semarchive, a rough count of plural pattern frequencies was undertaken. The FSP proved to be less frequent than BPs in tokens and can thus be considered a minority default, a finding that calls into question the validity of Boudelaa and Gaskell’s corpus (2002. A re-examination of the default system for Arabic plurals. Language and Cognitive Processes 17(3). 321–343) on JA. Although 3- to 5-year-old children use the FSP as the most productive pattern, frequency does not significantly contribute to the predictability of the distribution in shaping the correct plural form at this stage of learning BPs.

Comparative Performance of Popular Methods for Hybrid Detection using Genomic Data

Interspecific hybridization is an important evolutionary phenomenon that generates genetic variability in a population and fosters species diversity in nature. The availability of large genome scale datasets has revolutionized hybridization studies to shift from the examination of the presence or absence of hybrids in nature to the investigation of the genomic constitution of hybrids and their genome-specific evolutionary dynamics. Although a handful of methods have been proposed in an attempt to identify hybrids, accurate detection of hybridization from genomic data remains a challenging task. The available methods can be classified broadly as site pattern frequency based and population genetic clustering approaches, though the performance of the two classes of methods under different hybridization scenarios has not been extensively examined. Here, we use simulated data to comparatively evaluate the performance of four tools that are commonly used to infer hybridization events: the site pattern frequency based methods HyDe and the D-statistic (i.e., the ABBA-BABA test), and the population clustering approaches structure and ADMIXTURE. We consider single hybridization scenarios that vary in the time of hybridization and the amount of incomplete lineage sorting (ILS) for different proportions of parental contributions (γ); introgressive hybridization; multiple hybridization scenarios; and a mixture of ancestral and recent hybridization scenarios. We focus on the statistical power to detect hybridization, the false discovery rate (FDR) for the D-statistic and HyDe, and the accuracy of the estimates of γ as measured by the mean squared error for HyDe, structure, and ADMIXTURE. Both HyDe and the D-statistic demonstrate a high level of detection power in all scenarios except those with high ILS, although the D-statistic often has an unacceptably high FDR. The estimates of γ in HyDe are impressively robust and accurate whereas structure and ADMIXTURE sometimes fail to identify hybrids, particularly when the proportional parental contributions are asymmetric (i.e., when γ is close to 0). Moreover, the posterior distribution estimated using structure exhibits multimodality in many scenarios, making interpretation difficult. Our results provide guidance in selecting appropriate methods for identifying hybrid populations from genomic data.