A New Stochastic Time-Cost-Quality Trade-Off Project Scheduling Problem Considering Multiple-Execution Modes, Preemption, and Generalized Precedence Relations

Reza-Pour, Farahnaz,Khalili-Damghani, Kaveh Korean Institute of Industrial Engineers 2017 Industrial Engineeering & Management Systems Vol.16 No.3

Project managers always try to make the best decisions in order to complete their projects in the shortest period of time, with the least amount of costs, and with the highest degree of quality. Therefore, the process of decision-making is conducted in a triangle of time, costs, and quality. This triangle is a crucial part of management process throughout the execution of the project. However, in all problems, some unpredictable situations may be faced. In such situations, some or all parameters of the problem are expressed by uncertain variables. In this paper, a stochastic time-cost-quality trade off project scheduling problem (STCQTP) considering multiple-execution modes, preemption, and generalized precedence relations is developed. In order to solve the STCQTP, a hybrid solution approach based on Stochastic Chance Constraint Programming (SCCP) and Goal Programming (GP) is proposed. SCCP and GP are used to handle the uncertain nature and multiple-objectives of STCQTP, respectively. Numerical example is solved in order to illustrate the applicability of proposed model and solution approach.

A New Stochastic Time-Cost-Quality Trade-Off Project Scheduling Problem Considering Multiple-Execution Modes, Preemption, and Generalized Precedence Relations

Farahnaz Reza-Pour,Kaveh Khalili-Damghani 대한산업공학회 2017 Industrial Engineeering & Management Systems Vol.16 No.3

Project managers always try to make the best decisions in order to complete their projects in the shortest period of time, with the least amount of costs, and with the highest degree of quality. Therefore, the process of decision-making is conducted in a triangle of time, costs, and quality. This triangle is a crucial part of management process throughout the execution of the project. However, in all problems, some unpredictable situations may be faced. In such situations, some or all parameters of the problem are expressed by uncertain variables. In this paper, a stochastic time-costquality trade off project scheduling problem (STCQTP) considering multiple-execution modes, preemption, and generalized precedence relations is developed. In order to solve the STCQTP, a hybrid solution approach based on Stochastic Chance Constraint Programming (SCCP) and Goal Programming (GP) is proposed. SCCP and GP are used to handle the uncertain nature and multiple-objectives of STCQTP, respectively. Numerical example is solved in order to illustrate the applicability of proposed model and solution approach.

Retinopathy of Prematurity-assist: Novel Software for Detecting Plus Disease

Elias Khalili Pour,Hamidreza Pourreza,Kambiz Ameli Zamani,Alireza Mahmoudi,Arash Mir Mohammad Sadeghi,Mahla Shadravan,Reza Karkhaneh,Ramak Rouhi Pour,Mohammad Riazi Esfahani 대한안과학회 2017 Korean Journal of Ophthalmology Vol.31 No.6

Purpose: To design software with a novel algorithm, which analyzes the tortuosity and vascular dilatation infundal images of retinopathy of prematurity (ROP) patients with an acceptable accuracy for detecting plus disease. Methods: Eighty-seven well-focused fundal images taken with RetCam were classified to three groups of plus,non-plus, and pre-plus by agreement between three ROP experts. Automated algorithms in this study weredesigned based on two methods: the curvature measure and distance transform for assessment of tortuosityand vascular dilatation, respectively as two major parameters of plus disease detection. Results: Thirty-eight plus, 12 pre-plus, and 37 non-plus images, which were classified by three experts, weretested by an automated algorithm and software evaluated the correct grouping of images in comparison toexpert voting with three different classifiers, k-nearest neighbor, support vector machine and multilayer perceptronnetwork. The plus, pre-plus, and non-plus images were analyzed with 72.3%, 83.7%, and 84.4%accuracy, respectively. Conclusions: The new automated algorithm used in this pilot scheme for diagnosis and screening of patientswith plus ROP has acceptable accuracy. With more improvements, it may become particularly useful, especiallyin centers without a skilled person in the ROP field.

Probabilistic Convective Initiation Nowcasting with Reduced Satellite - NWP Predictors over Iran

Reza Khandan,Seyed Kazem Alavipanah,Arastoo Pour Biazar,Maryam Gharaylou 한국기상학회 2018 Asia-Pacific Journal of Atmospheric Sciences Vol.54 No.3

Geostationary satellites are able to nowcast Convective Initiation (CI) for the next 0–6 h. Compared to using satellite predictors only, the incorporation of satellite and NumericalWeather Prediction (NWP) predictors can provide the possibility to reduce false alarm rates in 0–1:30 Convective Initiation Nowcasting (COIN). However, the correlation among these predictors not only can cause error in COIN, but also increases the runtime. In this study for the first time, all effective predictors in Satellite Convection Analysis and Tracking version 2 (SATCASTv2) and NWP were applied over Iran from22ndMarch 2015 to 9th January 2016. In applying SATCASTv2 over Iran, it was necessary to make some modifications to the algorithm, such as removing case specific thresholds of satellite predictors and rearranging COIN predictors. Then, SATCASTv2 was tested and evaluated with both the full and reduced set of predictors. The results suggested that using fixed thresholds for temporal difference predictors could miss COIN in some cases. To investigate the possibility of improving computational efficiency, a dimension reduction was conducted by Factor Analysis (FA) and the number of predictors was reduced from 22 to 11. TheNWP-satellite, reduced NWP-satellite, and satellite predictors were used as input in Random Forest (RF), as a parametric machine learning method, for COIN evaluation. The Combination ofNWP model and satellite predictors had lower false alarm rates in contrast with satellite predictors. This is in agreement with previous studies. The results from statistical metrics showed that the reduced NWP-satellite predictors had comparable performance to the NWP-satellite predictors over study area, but decreased the run time by almost 50%. The results indicated that Convective Inhibition (CIN) was the most significant predictor when the reduced set of predictors was used.

Kinetics study of CO hydrogenation on a precipitated iron catalyst

Ali Nakhaei Pour,Mohammad Reza Housaindokht,Jamshid Zarkesh,Mohammad Irani,Ensieh Ganji Babakhani 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.2

The kinetics of the gas–solid Fischer–Tropsch synthesis over a precipitated Fe/Cu/La/SiO2 catalyst was studied in a well mixed, continuous spinning basket reactor. A wide range of synthesis gas conversions have been obtained by varying experimental conditions. Several Langmuir–Hinshelwood–Hougen–Watson type rate equations were derived based on detailed sets of possible reaction mechanisms originating from the carbide, enolic and combined enol/carbide mechanisms. Three models for the Fischer–Tropsch reaction rate were fitted to the experimental reaction rates. Kinetic parameters of models are determined using the genetic algorithm approach (GA), followed by the Levenberg–Marquardt (LM) method to make refined optimization, and are validated by means of statistical analysis. Simulations using the optimal kinetic models derived showed good agreement with experimental data.

Evaluation of Methylobacterium radiotolerance and Sphyngomonas yanoikoaie in Sentinel Lymph Nodes of Breast Cancer Cases

Yazdi, Hamid Reza,Movafagh, Abolfazl,Fallah, Fateme,Shargh, Shohreh Alizadeh,Mansouri, Neda,Pour, Atefeh Heidary,Hashemi, Mehrdad Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.no.sup3

It has been established that different kinds of bacteria agents are involved in various cancers. Although the mechanism of tumorigenesis is not clearly understood, there is evidence for the presence of bacteria within tumors, with at least a progression effect for some bacteria that prepare suitable microenvironments for tumor cell growth. The aim of current study was to evaluate bacterial dysbiosis in sentinel lymph nodes of breast cancer patients. One hundred and twenty three fresh-frozen sentinel lymph nodes and a corresponding number of normal adjacent breast tissue specimens and five normal mastectomy samples were investigated employing RT-PCR. In addition using genus-specific primers were applied. There was a significant differences as presence of Methylobacterium radiotolerance DNA recorded between patients and normal control group (p= 0.0). Based on our research work, further studies into the role of microbes in breast cancer would be of great interest.

Size dependence on reduction kinetic of iron based Fischer–Tropsch catalyst

Ali Nakhaei Pour,Mohammad Reza Housaindokht,Ensieh Ganji Babakhani,Mohammad Irani,Seyed Mehdi Kamali Shahri 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.3

Catalyst structure has a significant influence on its kinetic behavior. In this work, effect of nanoparticle size on reduction kinetics of iron FTS catalyst [0] has been studied. Fe/Cu/La catalysts were prepared via bulk precipitation and microemulsion methods to produce a series of iron oxides with different particle size. In microemulsion method, the catalyst particle size was changed with type of surfactant such as SDS, Triton X-100, and SDBS. Size dependence on reduction rate constant (kr) was evaluated using the formation and growth of nuclei model (3D). The results showed that when the catalyst particle size increased, the reduction rate of iron catalyst decreased. A value of 3.11 nm and 0.53 h1were obtained for h parameter and size independent part of reduction rate constant (k1), which are consistent with the values reported in literatures.

Sensory and Motor Behavior Evidences Supporting the Usefulness of Conditioned Medium from Dental Pulp-Derived Stem Cells in Spinal Cord Injury in Rats

Farzaneh Dehghani,Reza Asadi-Golshan,Vahid Razban,Esmaeil Mirzaei,Abdolkarim Rahmanian,Sahar Khajeh,Zohreh Mostafavi-Pour 대한척추외과학회 2018 Asian Spine Journal Vol.12 No.5

Study Design: Experimental animal study. Purpose: This study aimed to assess effects of conditioned medium (CM) of dental pulp-derived stem cells loaded in collagen hydrogel on functional recovery following spinal cord injury (SCI). Overview of Literature: SCI affects sensory and motor functions, and behavioral recovery is the most essential purpose of therapeutic intervention. Recent studies have reported that CM from dental pulp-derived stem cells has therapeutic benefits. In addition, collagen hydrogel acts as a drug delivery system in SCI experiments. Methods: Stem cells from human exfoliated deciduous teeth (SHEDs) were cultured, and SHED-CM was harvested and concentrated. Collagen hydrogel containing SHED-CM was prepared. The rats were divided into five groups receiving laminectomy, compressive SCI with or without intraspinal injection of biomaterials (SHED-CM), and collagen hydrogel with or without SHED-CM. Basso, Beattie, and Bresnahan (BBB) scoring, inclined plane, cold allodynia, and beam walk tests were performed for 6 weeks to assess locomotor, motor, sensory, and sensory-motor performances, respectively. Results: Scores of the rats receiving SHED-CM loaded in collagen hydrogel were significantly better than those of the other injured groups at 1-week post-injury for BBB, 2 weeks for inclined plane, 2 weeks for cold allodynia, and 4 weeks for beam walk tests (p <0.05). The differences remained significant throughout the study. Conclusions: Intraspinal administration of SHED-CM loaded in collagen hydrogel leads to improved functional recovery and proposes a cell-free therapeutic approach for SCI.

Studies on product distribution of nanostructured iron catalyst in Fischer–Tropsch synthesis: Effect of catalyst particle size

Ali Nakhaei Pour,Mohammad Reza Housaindokht 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.2

The dependencies of hydrocarbon product distributions of Fischer–Tropsch synthesis by iron catalystson catalysts particle size are studied. The concept of two superimposed Anderson–Schulz–Florydistributions applied for represent size dependency of product distributions. A series of catalysts withdifferent particle size are prepared by microemulsion method. It is found that the carbon number ofproduced hydrocarbon decreased with decreasing the catalyst particle size. These results indicate the H2concentration on catalyst surface decreased by increasing the catalyst particle size. Thus theconcentration of monomers that exhibited higher degree of hydrogenation (like CH2 species) on thesurface of catalyst increased with decreasing the catalyst particle size.

Studies of carbonaceous species in alkali promoted iron catalysts during Fischer–Tropsch synthesis

Ali Nakhaei Pour,Mohammad Reza Housaindokht,Jamshid Zarkesh,Sayyed Faramarz Tayyari 한국공업화학회 2010 Journal of Industrial and Engineering Chemistry Vol.16 No.6

The effects of La, Mg and Ca promoters on carbonaceous surface and bulk iron carbide species formed in the alkali promoted iron catalysts are studied under realistic Fischer–Tropsch synthesis (FTS) conditions. Compositions of bulk iron phase and phase transformations of carbonaceous species during pretreatment and FTS reaction were characterized using the temperature-programmed surface reaction with hydrogen (TPSR-H2) and XRD techniques. Many carbonaceous species on surface and bulk were qualitatively and quantitatively identified by combined TPSR-H2 and XRD spectra of the alkali promoted iron catalyst. These species, sorted by the their reactivity with H2 from high to low, were recognized as (a) adsorbed, atomic carbon; (b) amorphous, lightly polymerized hydrocarbon or carbon surface species;(c) bulk carbides and (d) disordered and moderately ordered graphitic surface carbons. The results revealed that while the surface basicity of the iron catalyst increased the CO dissociation proceeds faster than carbon hydrogenation. This phenomenon leads to excessive carbon deposition and formation of inactive iron carbide phases and graphitic type carbonaceous surface species, and consequently leads to catalyst deactivation. 2010 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.