Generalized formulation of linear nonquadratic weighted optimal error shaping guidance laws

This study presents a novel extension to the theory of optimal guidance laws represented by the nontraditional class of performance indices: nonquadratic-type signal Lp" role="presentation">Lp norm for the input weighted by an arbitrary positive function. Various missile guidance problems are generally formulated into a scalar terminal control problem based on the understanding of the predictor–corrector nature. Then, a new approach to derive the optimal feedback law, minimizing the nonquadratic performance index, is proposed by using the Hölderian inequality. The proposed extension allows a more general family of formulations for the design of closed-form feedback solutions to various guidance problems to be treated in a unified framework. The equivalence between the proposed approach and other design methodologies is investigated. In general, the type of input norm mainly determines the variability of input during the engagement while trading off against the rate of error convergence. The analytic solution derived in this study is verified by comparison with the solution from numerical optimization, and the effect of the exponent p" role="presentation">p in the performance index on the trajectory and command is demonstrated by numerical simulations

Composite model reference adaptive control with parameter convergence under finite excitation

A new parameter estimation method is proposed in the framework of composite model reference adaptive control for improved parameter convergence without persistent excitation. The regressor filtering scheme is adopted to perform the parameter estimation with signals that can be obtained easily. A new framework for residual signal construction is proposed. The incoming data is first accumulated to build the information matrix, and then its quality is evaluated with respect to a chosen measure to select and store the best one. The information matrix is built to have full rank after sufficient but not persistent excitation. In this way, the exponential convergence of both tracking error and parameter estimation error can be guaranteed without persistent oscillation in the external command which drives the system. Numerical simulations are performed to verify the theoretical findings and to demonstrate the advantages of the proposed adaptation law over the standard direct adaptation law

Are Histrionic Personality Traits Associated with Irritability during Conscious Sedation Endoscopy?

Aim. We aimed to evaluate whether histrionic personality traits are associated with irritability during conscious sedation endoscopy (CSE). Materials and Methods. A prospective cross-sectional study was planned. Irritability during CSE was classified into five grades: 0, no response; I, minimal movement; II, moderate movement; III, severe movement; IV, fighting against procedure. Patients in grades III and IV were defined as the irritable group. Participants were required to complete questionnaire sheet assessing the extent of histrionic personality traits, extraversion-introversion, and current psychological status. The present authors also collected basic sociodemographic data including alcohol use history. Results. A total of 32 irritable patients and 32 stable patients were analyzed. The histrionic personality trait score of the irritable group was higher than that of the stable group (9.5 ± 3.1 versus 6.9 ± 2.9; P = 0.001), as was the anxiety score (52.8 ± 8.6 versus 46.1 ± 9.6; P = 0.004). Heavy alcohol use was more frequently observed in the irritable group (65.6% versus 28.1%; P = 0.003). In multivariate analysis, all these three factors were independently correlated with irritability during CSE. Conclusion. This study revealed that histrionic personality traits, anxiety, and heavy alcohol use can affect irritability during CSE

The Validity of Translation Tasks as an EFL Reading Comprehension Assessment Method in Korean High School Classrooms

2008This study attempts to investigate the validity of translation tasks as a reading comprehension assessment in Korean high school classrooms and to identify the traits of the students who are good readers of English but not good translators. First the study explores the correlation between a translation task and a recall task for reading comprehension. Results showed a significant correlation between the two task scores (r=.902, p<0.01). However, there was a discrepancy between the High English Proficiency (HEP) and the Low English Proficiency (LEP) groups (r=.777, p<0.01) vs. (r=.912, p<0.01). Five students from the HEP group showed a significant discrepancy in z-‐ scores of the two tasks. In an attempt to identify the reasons for the discrepancy, the study reports the English learning backgrounds, reading habits and attitude of the five students. An interview of the students revealed that those who are good readers of English but not good translators learned English from native speakers of English or in an English speaking environment beginning at an early age and had less experience in reading classes taught through the grammartranslation method. The findings suggest that despite the close correlation between recall and translation tasks, assessing reading comprehension through translation may fail to identify students who are already good readers of English but not good translators

A case report of type VI dual left anterior descending coronary artery anomaly presenting with non-ST-segment elevation myocardial infarction

BACKGROUND: Type VI dual left anterior descending artery (LAD) is a rare coronary anomaly, the first case of which has recently been described. This is the first report of type VI dual LAD anomaly in which the patient presented with non-ST-segment elevation myocardial infarction and percutaneous coronary intervention was performed in the anomalously originating LAD. CASE PRESENTATION: A 52-year-old man with diabetes, hypertension and hyperlipidemia presented with chest pain without ST elevation on EKG, although the patient’s troponin I level was elevated. Coronary angiography revealed a short LAD originating from the left main coronary artery and a long LAD originating from the proximal portion of the right coronary artery (RCA). Three-dimensional reconstruction of computed tomography of images revealed that the long LAD originated from the proximal RCA and coursed between the right ventricular outflow tract (RVOT) and the aortic root before entering the mid anterior interventricular groove. The high take-off RCA originated underneath the RVOT, pointing downwards and forming an acute angle with the proximal portion of the long LAD. The anomalous long LAD displayed significant stenosis. We performed successful percutaneous coronary intervention (PCI) in the anomalous artery. CONCLUSION: With accurate understanding of the coronary anatomy and appropriate hardware selection, successful PCI can be performed in the in the long LAD in patients with type VI dual LAD anomaly

EFFECTS OF MO, CR, AND V ADDITIONS ON TENSILE AND CHARPY IMPACT PROPERTIES OF API X80 PIPELINE STEELS

In this study, four API X80 pipeline steels were fabricated by varying Mo, Cr, and V additions, and their microstructures and crystallographic orientations were analyzed to investigate the effects of their alloying compositions on tensile properties and Charpy impact properties. Because additions of Mo and V promoted the formation of fine acicular ferrite (AF) and granular bainite (GB) while prohibiting the formation of coarse GB, they increased the strength and upper-shelf energy (USE) and decreased the energy transition temperature (ETT). The addition of Cr promoted the formation of coarse GB and hard secondary phases, thereby leading to an increased effective grain size, ETT, and strength, and a decreased USE. The addition of V resulted in a higher strength, a higher USE, a smaller effective grain size, and a lower ETT, because it promoted the formation of fine and homogeneous of AF and GB. The steel that contains 0.3 wt pct Mo and 0.06 wt pct V without Cr had the highest USE and the lowest ETT, because its microstructure was composed of fine AF and GB while its maintained excellent tensile properties.X1126sciescopu

AFJPDA: a multiclass multi-object tracking with appearance feature-aided joint probabilistic data association

This study addresses a multiclass multi-object tracking problem in consideration of clutters in the environment. To alleviate issues with clutters, we propose the appearance feature-aided joint probabilistic data association filter. We also implemented simple adaptive gating logic for the computational efficiency and track maintenance logic, which can save the lost track for re-association after occlusion or missed detection. The performance of the proposed algorithm was evaluated against a state-of-the-art multi-object tracking algorithm using both multiclass multi-object simulation and real-world aerial images. The evaluation results indicate significant performance improvement of the proposed method against the benchmark state-of-the-art algorithm, especially in terms of reduction in identity switches and fragmentation.This research was supported by the UK Research and Innovation-funded project HADO: project number 1002481

Building relationships through integrated online media platforms: Analysis of top 100 global brands

Many studies have examined organizations’ use of specific types of online media, but few studies have examined how organizations generate dialogues and develop relationships by using multiple online communication platforms. This study takes an integrated approach by examining how top global organizations incorporate brand Web sites, Facebook, and Twitter to cultivate relationships with stakeholders. Its findings suggest that those particular online media are used similarly, that is, more for information dissemination than user engagement and more for one-way than two-way communication. The findings also suggest that the types of products promoted can affect the way that organizations use different online media to develop relationships

Rates and subsequent clinical course of fetal congenital anomalies detected by prenatal targeted ultrasonography of 137 cases over 5 years in a single institute: a retrospective observational study

Background With the establishment of international guidelines and changes in insurance policies in Korea, the role of targeted ultrasonography has increased. This study aimed to identify the rates and clinical course of anomalies detected using prenatal targeted ultrasonography. Methods This study was a retrospective analysis of all pregnancies with targeted ultrasonography performed in a single secondary medical center over 5 years. Results Fetal anomalies were detected by targeted ultrasonography in 137 of the 8,147 cases (1.7%). The rates of anomalies were significantly higher in female fetuses (2.0% vs. 1.3%). In cases of female fetuses, the rate of anomalies was significantly higher in the advanced maternal age group (2.4% vs. 1.2%). In cases of male fetuses, the rate of anomalies was significantly higher in nulliparous (2.4% vs. 1.5%) and twin (5.7% vs. 1.9%) pregnancies. Pulmonary anomalies were significantly more common in the multiparity group (17.6% vs. 5.8%). Among the 137 cases, 17.5% terminated the pregnancy, 16.8% were diagnosed as normal after birth, and 42.3% were diagnosed with anomalies after birth or required follow-up. Conclusion Through the first study on the rates and clinical course of anomalies detected by targeted ultrasonography at a single secondary center in Korea, we found that artificial abortions were performed at a high rate, even for relatively mild anomalies or anomalies with good prognosis. We suggest the necessity of a nationwide study to establish clinical guidelines based on actual incidences or prognoses