Deceleration-Time Data for the Verification of Calculation Models of the Penetration with Erosion in Target

Author(s):  
MIKHAIL SOTSKIY ◽  
VLADISLAV VELDANOV
2017 ◽  
Vol 9 (7) ◽  
pp. 168781401770559 ◽  
Author(s):  
Qing Song ◽  
Yongxiang Dong ◽  
Miao Cui ◽  
Bin Yu

A method for predicting the residual velocity and deceleration of a projectile during normal low-velocity impact on a 2024-O thin aluminium plate is developed based on the similarity theory. Geometric scaling, the dissimilar materials of the projectile and different target thicknesses are considered. By a similitude analysis, the simulation criteria between the modelling and prototype experiments are obtained. The dimensionless velocity and deceleration of a projectile can be predicted by the relationship equations with the dimensionless dynamic pressure, projectile density and target thickness. On the basis of experimental data, the dimensionless residual velocity relationship is obtained and verified. In the range of normalised target thicknesses of [Formula: see text] (where H is target thickness and [Formula: see text] is projectile diameter), the deceleration–time data during penetration is simplified as a triangular wave. Moreover, it can be characterised using the maximum deceleration, the time to the maximum deceleration and the period of the triangular wave. Through a simulation analysis, three dimensionless deceleration characteristics of the projectile are developed to replicate a prototype-like deceleration–time process in a scaled model.


2018 ◽  
Vol 22 (1) ◽  
pp. 112-125 ◽  
Author(s):  
Yong Peng ◽  
Hao Wu ◽  
Qin Fang ◽  
Ziming Gong

Deceleration time histories of the 25.3 mm diameter, 428 g projectile penetration/perforation into 41 MPa reinforced concrete slabs with thicknesses of 100, 200, and 300 mm, are discussed. An ultra-high g small-caliber deceleration data recorder with a diameter of 18 mm is employed to digitize and record the acceleration during launch in the barrel, as well as the deceleration during penetration or perforation into targets. The accelerometer mounted in the data recorder measures rigid-body projectile deceleration as well as structural vibrations. To validate these complex signals, a validation approach for the accuracy of the recorded deceleration time data is proposed based on frequency characteristic analyses and signal integrations, and three sets of whole-range deceleration time data are validated. As the deceleration of the rigid-body projectile is the main concern, a signal processing approach is further given to obtain the rigid-body deceleration data, that is, using a low-pass filter to remove the high-frequency responses associated with vibrations of the projectile case and the internal supporting structure. The first valley frequency from the spectrum analysis is determined to be the critical cutoff frequency. To verify the accuracies of the theoretical model and the numerical simulation in predicting projectile motion time histories, theoretical projectile penetration/perforation deceleration time models are given and numerical simulations are performed. The predicted projectile time histories consist well with the validated deceleration time test data, as do their corresponding velocity and displacement time curves.


GeroPsych ◽  
2011 ◽  
Vol 24 (4) ◽  
pp. 169-176 ◽  
Author(s):  
Philippe Rast ◽  
Daniel Zimprich

In order to model within-person (WP) variance in a reaction time task, we applied a mixed location scale model using 335 participants from the second wave of the Zurich Longitudinal Study on Cognitive Aging. The age of the respondents and the performance in another reaction time task were used to explain individual differences in the WP variance. To account for larger variances due to slower reaction times, we also used the average of the predicted individual reaction time (RT) as a predictor for the WP variability. Here, the WP variability was a function of the mean. At the same time, older participants were more variable and those with better performance in another RT task were more consistent in their responses.


2009 ◽  
Vol 14 (2) ◽  
pp. 109-119 ◽  
Author(s):  
Ulrich W. Ebner-Priemer ◽  
Timothy J. Trull

Convergent experimental data, autobiographical studies, and investigations on daily life have all demonstrated that gathering information retrospectively is a highly dubious methodology. Retrospection is subject to multiple systematic distortions (i.e., affective valence effect, mood congruent memory effect, duration neglect; peak end rule) as it is based on (often biased) storage and recollection of memories of the original experience or the behavior that are of interest. The method of choice to circumvent these biases is the use of electronic diaries to collect self-reported symptoms, behaviors, or physiological processes in real time. Different terms have been used for this kind of methodology: ambulatory assessment, ecological momentary assessment, experience sampling method, and real-time data capture. Even though the terms differ, they have in common the use of computer-assisted methodology to assess self-reported symptoms, behaviors, or physiological processes, while the participant undergoes normal daily activities. In this review we discuss the main features and advantages of ambulatory assessment regarding clinical psychology and psychiatry: (a) the use of realtime assessment to circumvent biased recollection, (b) assessment in real life to enhance generalizability, (c) repeated assessment to investigate within person processes, (d) multimodal assessment, including psychological, physiological and behavioral data, (e) the opportunity to assess and investigate context-specific relationships, and (f) the possibility of giving feedback in real time. Using prototypic examples from the literature of clinical psychology and psychiatry, we demonstrate that ambulatory assessment can answer specific research questions better than laboratory or questionnaire studies.


2018 ◽  
Vol 30 (3) ◽  
pp. 328-338 ◽  
Author(s):  
Maria Bertling ◽  
Jonathan P. Weeks

2019 ◽  
Vol 2 (1) ◽  
pp. 217-222
Author(s):  
Dhio Emerko Ginting ◽  
Fani Ade Irma ◽  
Sri Rezeki Arbaningsih ◽  
Siti Hajar

WHO telah menetapkan Indonesia sebagai negara dengan jumlah perokok terbesar ketiga. Ada tiga zat kimia yang paling sangat berbahaya, yaitu tar, nikotin, karbon monoksida yang terkandung dalam rokok. Hasil penelitian di Inggris menunjukkan kepada kita bahwa kurang lebih 50% perokok yang merokok sejak remaja mengalami kematian akibat penyakit yang berhubungan dengan kebiasaan merokok mereka. Penelitian ini bertujuan untuk mengetahui tentang pengaruh asap rokok dengan proses kaskade clotting time. Jenis penelitian ini adalah penelitian analitik dengan menggunakan desain cross-sectional. Penelitian ini menggunakan sampel populasi laki-laki di Fakultas Kedokteran di UMSU yang diwawancara untuk mengetahui bahwa mereka merokok atau tidak, setelah itu, sampel diperiksa clotting time dan bleeding time. Data yang terkumpul dianalisis dengan uji chi-square. Hasil penelitian menunjukkan p = 0,000 bahwa ada hubungan merokok dengan clotting time dan bleeding time pada perokok berat dan sedang. Pada perokok berat dan moderat terdapat hubungan bermakna antara penurunan bleeding time dan peningkatan clotting time dengan merokok. Tidak ada hubungan antara clotting time dan merokok pada perokok ringan.


2019 ◽  
Vol 11 (1) ◽  
pp. 41-50
Author(s):  
Heni Purwaningsih ◽  
Umi Aniroh ◽  
Eko Mardiyaningsih

Program pembangunan kesehatan di Indonesia masih berfokus pada upaya peningkatan derajat kesehatan ibu dan anak terutama pada masa prenatal. Hal ini disebabkan masih tingginya Angka Kematian Ibu (AKI) dan Angka Kematian Bayi (AKB). ASI yang diberikan sejak usia dini dan dilanjutkan dengan ASI eksklusif selama 6 bulan dapat menurunkan angka kesakitan dan angka kematian bayi serta meningkatkan tumbuh kembang bayi secara optimal.  Penelitian ini bertujuan untuk mengetahui efektifitas pemberian konseling laktasi terhadap pelaksanaan menyusui pada ibu hamil trimester III. Desain penelitian menggunakan quasi eksperimen dengan rancangan One Group Pre-test dan  Post-test Desain. Populasi dalam penelitian ini adalah ibu hamil trimester III dan sampel yang diambil adalah 18 ibu hamil. Alat penggumpulan data menggunakan lembar observasi BREAST (body position, respons, emotional bonding, anatomy dan sucking time). Analisis data menggunakan wilcoxon.Hasil penelitian didapatkan pelaksanaan menyusui sebelum dilakukan konseling laktasi dalam kategori kurang (72,2%) sedangkan pelaksanaan menyusui setelah dilakukan konseling laktasi (77,8%) dalam kategori baik. Konseling laktasi efektif dilakukan untuk meningkatkan pelaksanaan menyusui denganp-value 0,003 (p<0,005).Konseling laktasi seharusnya diberikan pada masa prenatal sehingga pada saat postpartum, ibu sudah mampu memberikan asi secara maksimal. Pendampingan terhadap ibu hamil juga berperan dalam pelaksanaan pemberian ASI.   Kata kunci : Konseling laktasi, ASI, pelaksanaan menyusui   THE EFFECTIVENESS OF LACTATION COUNSELING IN THE 3rd TRIMESTER PREGNANT WOMEN ON BREASTFEEDING IMPLEMENTATION   ABSTRACT Indonesia's health development program still focuses on improving mother and child health, especially at the prenatal stage. It is due to the high maternal mortality rate (MMR) and Infant Mortality Rate (IMR). Breastmilk given from an early age and continued with exclusive breastfeeding for six months can reduce infants morbidity and mortality rate and increase their optimal growth. The purpose is to investigate the effectiveness of lactation counseling to the implementation of breastfeeding in third-trimester. The study design used quasi experiments with one group pre-test and post-test. Population was the 3rd-trimester pregnant mothers, and the samples were 18 mothers. The data collection tool used BREAST observation sheets (body position, response, emotional bonding, anatomy and sucking time). Data analysis used Wilcoxon. The result of the research shows that breastfeeding before lactation counseling is in less category (72,2%) while breastfeeding after lactation counseling (77,8%) is in a goodcategory. Effective lactation counseling is performed to improve the implementation of breastfeeding with p-value 0.003 (p <0.005). Lactation counseling should be given during the prenatal period so that at the time of postpartum, the mother has been able to give breastmilk maximally. Mentoring for pregnant women also plays a role in the implementation of breastfeeding Keywords: lactation counseling, breast milk, breastfeeding implementation


Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 399-P
Author(s):  
ANN MARIE HASSE ◽  
RIFKA SCHULMAN ◽  
TORI CALDER

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