REGULAR INJECTIVITY AND EXPONENTIABILITY IN THE SLICE CATEGORIES OF ACTIONS OF POMONOIDS ON POSETS

Farsad, Farideh,Madanshekaf, Ali Korean Mathematical Society 2015 대한수학회지 Vol.52 No.1

For a pomonoid S, let us denote Pos-S the category of S-posets and S-poset maps. In this paper, we consider the slice category Pos-S/B for an S-poset B, and study some categorical ingredients. We first show that there is no non-trivial injective object in Pos-S/B. Then we investigate injective objects with respect to the class of regular monomorphisms in this category and show that Pos-S/B has enough regular injective objects. We also prove that regular injective objects are retracts of exponentiable objects in this category. One of the main aims of the paper is to draw attention to characterizing injectivity in the category Pos-S/B under a particular case where B has trivial action. Among other things, we also prove that the necessary condition for a map (an object) here to be regular injective is being convex and present an example to show that the converse is not true, in general.

Channel and Noise Models for Nonlinear Molecular Communication Systems

Farsad, Nariman,Na-Rae Kim,Eckford, Andrew W.,Chan-Byoung Chae IEEE 2014 IEEE journal on selected areas in communications Vol.32 No.12

<P>Recently, a tabletop molecular communication platform has been developed for transmitting short text messages across a room. The end-to-end system impulse response for this platform does not follow previously published theoretical works because of imperfect receiver, transmitter, and turbulent flows. Moreover, it is observed that this platform resembles a nonlinear system, which makes the rich body of theoretical work that has been developed by communication engineers not applicable to this platform. In this work, we first introduce corrections to the previous theoretical models of the end-to-end system impulse response based on the observed data from experimentation. Using the corrected impulse response models, we then formulate the nonlinearity of the system as noise and show that through simplifying assumptions it can be represented as Gaussian noise. Through formulating the system's nonlinearity as the output a linear system corrupted by noise, the rich toolbox of mathematical models of communication systems, most of which are based on linearity assumption, can be applied to this platform.</P>

REGULAR INJECTIVITY AND EXPONENTIABILITY IN THE SLICE CATEGORIES OF ACTIONS OF POMONOIDS ON POSETS

Farideh Farsad,Ali Madanshekaf 대한수학회 2015 대한수학회지 Vol.52 No.1

For a pomonoid S, let us denote Pos-S the category of S-posets and S-poset maps. In this paper, we consider the slice cate- gory Pos-S/B for an S-poset B, and study some categorical ingredients. We first show that there is no non-trivial injective object in Pos-S/B. Then we investigate injective objects with respect to the class of regu- lar monomorphisms in this category and show that Pos-S/B has enough regular injective objects. We also prove that regular injective objects are retracts of exponentiable objects in this category. One of the main aims of the paper is to draw attention to characterizing injectivity in the cate- gory Pos-S/B under a particular case where B has trivial action. Among other things, we also prove that the necessary condition for a map (an ob- ject) here to be regular injective is being convex and present an example to show that the converse is not true, in general.

On Generators in the Category of Actions of Pomonoids on Posets and its Slices

Farideh, Farsad,Ali, Madanshekaf Department of Mathematics 2022 Kyungpook mathematical journal Vol.62 No.4

Where S is a pomonoid, let Pos-S be the category of S-posets and S-poset maps. We start off by characterizing the pomonoids S for which all projectives in this category are either generators or free. We then study the notions of regular injectivity and weakly regularly d-injectivity in this category. This leads to homological classification results for pomonoids. Among other things, we get find relationships between regular injectivity in the slice category Pos-S/BS, for any S-poset BS, and generators and cyclic projectives in Pos-S.

On the control of structural/compositional ratio of coherent order-disorder interfaces

Forghani, Farsad,Han, Jong Chan,Moon, Jongun,Abbaschian, Reza,Park, Chan Gyung,Kim, Hyoung Seop,Nili-Ahmadabadi, Mahmoud Elsevier 2019 JOURNAL OF ALLOYS AND COMPOUNDS Vol.777 No.-

<P><B>Abstract</B></P> <P>Order-disorder coherent interfaces determine the microstructure and mechanical properties of precipitation-hardened high-temperature alloys. The characteristics of these interfaces can be defined by a compositional width, δ, and structural width, δ′. The latter, which can be considered as the width of the ordered part of the interface, can play an important role in high-temperature mechanical behavior of precipitation-hardened alloys. This is due to the fact that diffusion in the ordered part of the interface is generally much slower than diffusion in the disordered phase, thus hindering the solid-state diffusion-based phenomena. Here, we investigate the order-disorder interface in a Ni-19Al (at.%) alloy as a model alloy for Ni-based superalloys using atomic-resolution scanning transmission electron microscopy and three-dimensional atom probe tomography. Then, we employ thermodynamic modeling to describe the interplay between the structural and compositional interface widths in binary Ni-Al and in ternary Ni-Al-Cr and Co-Al-W systems. We introduce the δ′/δ ratio as a critical parameter that varies significantly in different alloys. Our findings offer a general pathway to control the δ′/δ ratio of interfaces, which in turn affect the high-temperature properties of precipitation-hardened alloys.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Characterization of the order-disorder coherent interface in a Ni-19Al model alloy. </LI> <LI> Describing the dual nature of order-disorder coherent interfaces. </LI> <LI> Prediction of the structural interface width δ′ based on the thermodynamic modeling. </LI> <LI> Introducing the δ′/δ ratio as a critical parameter that varies in different alloys. </LI> </UL> </P>

Molecular communications: channel model and physical layer techniques

Guo, Weisi,Asyhari, Taufiq,Farsad, Nariman,Yilmaz, H. Birkan,Li, Bin,Eckford, Andrew,Chae, Chan-Byoung Institute of Electrical and Electronics Engineers 2016 IEEE wireless communications Vol.23 No.4

<P>This article examines recent research in molecular communications from a telecommunications system design perspective. In particular, it focuses on channel models and state-of-the-art physical layer techniques. The goal is to provide a foundation for higher layer research and motivation for research and development of functional prototypes. In the first part of the article, we focus on the channel and noise model, comparing molecular and radio-wave pathloss formulae. In the second part, the article examines, equipped with the appropriate channel knowledge, the design of appropriate modulation and error correction coding schemes. The third reviews transmitter and receiver side signal processing methods that suppress inter-symbol interference. Taken together, the three parts present a series of physical layer techniques that are necessary to produce reliable and practical molecular communications.</P>

A Psychological Model Applied to Mathematical Problem Solving

Hassan Alamolhodaei,Najmeh Farsad 韓國數學敎育學會 2009 수학교육연구 Vol.13 No.3

Factors Associated with Adherence to Colorectal Cancer Screening among Moderate Risk Individuals in Iran

Taheri-Kharameh, Zahra,Noorizadeh, Farsad,Sangy, Samira,Zamanian, Hadi,Shouri-Bidgoli, Ali Reza,Oveisi, Helaleh Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.18

Background: Colorectal cancer is one of the most common neoplasms in Iran. Secondary prevention (colorectal cancer screening) is important and a most valuable method of early diagnosis of this cancer. The objectives of this study were to determine the factors associated with colorectal cancer screening adherence among Iranians 50 years and older using the Health Belief Model. Materials and Methods: This cross-sectional study was conducted from June 2012 to May 2013. A convenience sample of 200 individuals aged 50 and older was recruited from the population at outpatient clinics in teaching hospitals. Data gathering tools were the Champions health belief model scale (CHBMS) with coverage of socio-demographic background and CRC screening information. Multiple logistic regression was performed to identify factors associated with colorectal cancer screening adherence. Results: The mean age of participants was $62.5{\pm}10.8$ and 75.5% were women. A high percentage of the participants had not heard or read about colorectal cancer (86.5%) and CRC screening (93.5%). Perceived susceptibility to colorectal cancer had the lowest percentage of all of the subscales. Participants who perceived more susceptibility (OR =2.99; CI 95%: 1.23-5.45) and reported higher knowledge (OR =1.29; CI 95%: 1.86-3.40) and those who reported fewer barriers (OR =.37; CI 95%:.21-.89), were more likely to have carried out colorectal cancer screening. Conclusions: Our findings indicated that CRC knowledge, perceived susceptibility and barriers were significant predictors of colorectal cancer screening adherence. Strategies to increase knowledge and overcome barriers in risk individuals appear necessary. Education programs should be promoted to overcome knowledge deficiency and negative perceptions in elderly Iranians.

SMIET: Simultaneous Molecular Information and Energy Transfer

Guo, Weisi,Deng, Yansha,Yilmaz, H. Birkan,Farsad, Nariman,Elkashlan, Maged,Eckford, Andrew,Nallanathan, Arumugam,Chae, Chan-Byoung IEEE 2018 IEEE wireless communications Vol.25 No.1

<P>The performance of communication systems is fundamentally limited by the loss of energy through propagation and circuit inefficiencies. The emergence of the Internet of Nano Things ecosystem means there is a need to design and build nanoscale energy efficient communication subsystems. In this article, we show that it is possible to achieve ultra low energy communications at the nanoscale, if diffusive molecules are used for carrying data. While the energy of electromagnetic waves will inevitably decay as a function of transmission distance and time, the energy in individual molecules does not. Over time, the receiver has an opportunity to recover some, if not all, of the molecular energy transmitted. The article demonstrates the potential of ultra-low energy SMIET through point-to-point systems, two different nano-relay systems, and multiple access systems. It also discusses the benefits of crowd energy harvesting compared to traditional wavebased systems.</P>

Comparative Chemical Composition and Antiproliferative Activity of Aerial Parts of Salvia leriifolia Benth. and Salvia acetabulosa L. Essential Oils Against Human Tumor Cell In Vitro Models

Monica R. Loizzo,Federica Menichini,Rosa Tundis,Marco Bonesi,Farsad Nadjafi,Antoine M. Saab,Natale Giuseppe Frega,Francesco Menichini 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.1

The aim of this work was to examine the chemical composition and antiproliferative activity of Salvia leriifolia Benth. and Salvia acetabulosa L. oils. S. leriifolia oil was characterized by 50 components, whereas 19 components were identified in S. acetabulosa. S. leriifolia oil was characterized by camphor (10.5%), 1,8-cineole (8.6%), camphene (6.2%), and α-pinene (4.7%). α-Pinene (52.3%), 1,8-cineole (27.7%), and camphor (6.7%) were the major components in S. acetabulosa oil. Both oils exerted a strong antiproliferative activity comparing with vinblastine against COR-L23 with 50% inhibitory concentration (IC50) values of 7.5 and 6.5μg/mL for S. leriifolia and S. acetabulosa, respectively. Salvia oils showed an interesting activity also on C32 (IC50=6.3 and 9.1μg/mL for S. acetabulosa and S. leriifolia, respectively). S. acetabulosa was also found to possess cytotoxic activity against renal adenocarcinoma (IC50=6.8μg/mL). The results clearly showed that for both Salvia species the antiproliferative activity could not be related to the major abundant compounds. Consequently, the minor components may be involved in some type of synergism with the other active compounds.