http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
On the Residual Empirical Distribution Function of Stochastic Regression with Correlated Errors
Zakeri, Issa-Fakhre,Lee, Sangyeol The Korean Statistical Society 2001 Communications for statistical applications and me Vol.8 No.1
For a stochastic regression model in which the errors are assumed to form a stationary linear process, we show that the difference between the empirical distribution functions of the errors and the estimates of those errors converges uniformly in probability to zero at the rate of $o_{p}$ ( $n^{-}$$\frac{1}{2}$) as the sample size n increases.
Zakeri Fatemeh,Vosoughi Mahsa,Maghsoudi Hafez,Denayer Joeri F. M. 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.4
Microporous titanosilicate ETS-4 zeotype membrane, with its 4 Å pore openings, is an adequate material for the kinetic separation of nitrogen from methane. Obtaining high N 2 /CH 4 permselectivity, small-sized ETS-4 powder was synthesized by aging method, and then utilized as membrane seeding powder. Highly N 2 -selective ETS-4 membranes were fabricated utilizing a new recipe and the secondary growth approach on α-alumina supports. XRD, FESEM, and EDX studies were used to analyze the synthesized ETS-4 powder and membranes. The eff ect of membrane activation temperature (80–140 °C) on permeance of N 2 was evaluated. In addition to N 2 and CH 4 , the membrane permeance was also evaluated for O 2 and Ar gases. Regarding the ETS-4 membranes, N 2 permeance increased gradually as the activation temperature was raised in the 80–140 °C range, reaching its highest value (i.e., 2.6 × 10 −8 mol m −2 s −1 Pa −1 ) after activation at 140 °C. The permeances of N 2 and CH 4 gases were measured at 30, 50, and 70 °C, and a pressure diff erence up to 600 kPa. N 2 /CH 4 permselectivity of 75.19 (N 2 permeance of 1.94 × 10 –8 mol m- 2 s −1 Pa −1 ) were obtained at 30 °C and 200 kPa of feed pressure. The results revealed that ETS-4 membranes have great potential for N 2 removal from natural gas due to highest N 2 /CH 4 permselectivity among the other membranes.
Zakeri Mohammadreza,Mirahmadizadeh Alireza,Azarbakhsh Habibollah,Dehghani Seyed Sina,Janfada Maryam,Moradian Mohammad javad,Moftakhar Leila,Sharafi Mehdi,Heiran Alireza 대한예방의학회 2024 예방의학회지 Vol.57 No.2
Objectives: The coronavirus disease 2019 (COVID-19) pandemic led to increased mortality rates. To assess this impact, this ecological study aimed to estimate the excess death counts in southern Iran.Methods: The study obtained weekly death counts by linking the National Death Registry and Medical Care Monitoring Center repositories. The P-score was initially estimated using a simple method that involved calculating the difference between the observed and expected death counts. The interrupted time series analysis was then used to calculate the mean relative risk (RR) of death during the first year of the pandemic.Results: Our study found that there were 5571 excess deaths from all causes (P-score=33.29%) during the first year of the COVID-19 pandemic, with 48.03% of these deaths directly related to COVID-19. The pandemic was found to increase the risk of death from all causes (RR, 1.26; 95% confidence interval [CI], 1.19 to 1.33), as well as in specific age groups such as those aged 35-49 (RR, 1.21; 95% CI, 1.12 to 1.32), 50-64 (RR, 1.38; 95% CI, 1.28 to 1.49), and ≥65 (RR, 1.29; 95% CI, 1.12 to 1.32) years old. Furthermore, there was an increased risk of death from cardiovascular diseases (RR, 1.17; 95% CI, 1.11 to 1.22).Conclusions: There was a 26% increase in the death count in southern Iran during the COVID-19 pandemic. More than half of these excess deaths were not directly related to COVID-19, but rather other causes, with cardiovascular diseases being a major contributor.
Zakeri, Zahra,Lockshin, Richard A. Elsevier 2019 Biochemical pharmacology Vol.162 No.-
<P><B>Abstract</B></P> <P>International Cell Death Society held its 25th meeting, entitled “About canonical, non-canonical, and immunogenic cell death: basic mechanisms and translational applications” in Seoul, South Korea, May 31-June 2, 2018, addressed the most current issues in the field. Now that many types and pathways of cell death are recognized, attention has turned to how the threshold to death is maintained or surpassed, and how and what intracellular signals control the process. Most of the speakers addressed these topics, focusing on mitochondria and on new high-resolution techniques that promise to answer current questions.</P>
Masoumeh Zakeri,Mohamed Mahmoud Nasef,Ebrahim Abouzari-Lotf,Arezoo Moharami,MAJID M. HERAVI 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.29 No.-
Green approaches to the synthesis of spiro-4H-pyrans are reported based on the one-pot and three-component condensation via a domino Knoevenagel/Michael/cyclization sequence. These approachesinvolve evaluation of the activity of several organocatalysts in water as a reaction media and also undersolvent-free in both microwave irradiation and ball milling conditions. Extensive experiments werecarried out to optimize the reaction parameters including type and amount of catalyst, reactiontemperature and time. Microwave irradiation in presence of 4-dimethylaminopyridine (DMAP) wasobserved as the best procedure with good yields, short reaction time, environmental friendliness, andconvenient operation.
Influence of stiffener edge on the buckling load of holed composite plates
Mahnaz Zakeri,Ali Mozaffari,Mohamad A. Katirae 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.29 No.5
In this paper, buckling load of edge stiffened composite plates is assessed. The effect of stiffener edge size, circular hole, and the fiber orientation angle on buckling behavior of composite plates under uni-axial compressive load is investigated. This paper includes two parts as experimental and numerical studies. L-shape composite plates are manufactured in three different layups. Then the buckling loads are experimentally determined. Subsequently, by using the numerical simulation, the size variation effects of stiffener edge and circular cutout on the plate buckling loads are analyzed in five different layups. The results show that cutout size, stiffener edge height and fiber orientation angle have important effects on buckling load. In addition, there is an optimum height for stiffener edge during different conditions.
Investigation on dynamic behavior of railway track in transition zone
Jabbar-Ali Zakeri,Vida Ghorbani 대한기계학회 2011 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.25 No.2
Railway track transition zone is a zone where track stiffness changes abruptly. This change occurs where the slab track connects to a conventional ballasted track, at the abutments of open-deck bridges, at the beginnings and ends of tunnels, at road and railway level crossings, and at locations where rigid culverts are placed close to the bottom of sleepers. In this paper, ballasted and slab tracks are simulated by two-dimensional model with two-layer masses. The transition zone is divided into three segments, each having a length of 6meters with different specification and stiffness. The model of track consists of a Timoshenko beam as a rail and slab, lumped mass as sleepers, and spring and damper as ballast, sub-grade, and rail pad. The results of the dynamic analysis are presented and compared in two circumstances – one considering the transition zone and the other its absence.
Field investigation on load distribution and deflections of railway track sleepers
Jabbar Ali Zakeri,Javad Sadeghi 대한기계학회 2007 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.21 No.12
Despite the significant role of sleepers in railway track mechanical behavior, no thorough mechanistic approach has been presented for the development of the loading pattern they experience. The current theoretical methods in the analysis of the railway track system need further calibration and verification using field-measured data. In this paper, using specific load-cells between sleepers and the rail and beneath the sleepers, the vertical loading conditions of these main track elements are studied. The lateral resistance of the concrete sleepers in the ballasted tracks is investigated by using full scale sleeper pull-out tests. Moreover, track deflections under the sleeper as the main track analysis parameter are measured and the results are discussed. In this paper, with the results obtained from extensive field measurements, some suggestions are made leading to an improvement in the current understanding of the sleeper loading pattern and the track deflections.
Sensitive Analysis of Track Parameters on Train- Track Dynamic Interaction
Jabbar Ali Zakeri,He Xia 대한기계학회 2008 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.22 No.7
Dynamic behavior of railway tracks when trains are running is influenced by several factors, i.e. rolling stock, the components of superstructure and their specifications. Usually, features like the sleeper spacing, rail pad stiffness, bal-last damping and stiffness have an effect on the dynamic response of the track. The best method to study the dynamic behavior of the track is to model the track assembly and the train as a whole and carry out an analysis of dynamic inter-action. Such analysis makes the identification of the tracks dynamic behavior easer and helps to anticipate the deterio-presents tracktrain dynamic interaction without considering irregularity of the rail face. A sensitivity analysis was carried out on the selected model. The analysis was undertaken with the view of varying one of the mentioned parame-ters and the results were presented to further identify the deterioration of the track elements. The results indicate that reducing sleeper spacing, rail pad stiffness, ballast stiffness, and increasing ballast damping reduces wheel-rail, rail-sleeper, and sleeper - ballast contact forces. Keywords
Mohammad Ali Zakeri,Adnan Rashid Aziz,Elham Rahiminezhad,Mahlagha Dehghan 대한중환자의학회 2024 Acute and Critical Care Vol.39 No.1
Background: Muscle weakness is prevalent in intensive care patients. This study focused on comparing the effects of massage and range of motion (ROM) exercises on muscle strength and intensive care unit-acquired weakness (ICU-AW) among patients with coronavirus disease 2019 (COVID-19). Methods: This study was a randomized clinical trial that recruited patients (n=45) with COVID-19 admitted to the ICU and divided them into three groups (ROM exercises, massage, and control). We evaluated muscle strength and ICU-AW in the arms and legs using a hand dynamometer. The Medical Research Council sum score was determined before and after the intervention. Results: The study findings were that 0%, 20%, and 100% of the participants in the ROM exercises, massage, and control groups had ICU-AW on the 7th day of ICU admission. The ROM exercise group had greater muscle strength in the hands and legs than the massage and control groups, and the massage group had greater muscle strength than the control group. Conclusions: Massage and ROM exercises could improve muscle strength and reduce ICU-AW in COVID-19 patients admitted to the ICU.