Modelling and Verification of a Cluster-tree Formation Protocol Implementation for the IEEE 802.15.4 TSCH MAC Operation Mode

Correct and efficient initialization of wireless sensor networks can be challenging in the face of many uncertainties present in ad hoc wireless networks. In this paper we examine an implementation for the formation of a cluster-tree topology in a network which operates on top of the TSCH MAC operation mode of the IEEE 802.15.4 standard, and investigate it using formal methods. We show how both the mCRL2 language and toolset help us in identifying scenarios where the implementation does not form a proper topology. More importantly, our analysis leads to the conclusion that the cluster-tree formation algorithm has a super linear time complexity. So, it does not scale to large networks.Comment: In Proceedings MARS 2017, arXiv:1703.0581

Communication Patterns in Mean Field Models for Wireless Sensor Networks

Wireless sensor networks are usually composed of a large number of nodes, and with the increasing processing power and power consumption efficiency they are expected to run more complex protocols in the future. These pose problems in the field of verification and performance evaluation of wireless networks. In this paper, we tailor the mean-field theory as a modeling technique to analyze their behavior. We apply this method to the slotted ALOHA protocol, and establish results on the long term trends of the protocol within a very large network, specially regarding the stability of ALOHA-type protocols.Comment: 22 pages, in LNCS format, Submitted to QEST'1

Novi pristup za poboljšanje karakteristika UPQC-a tijekom nesimetričnih i distorzijskih uvjeta tereta temeljen na teoriji trenutne snage

In order to deal with power quality problems under distortional and unbalanced load conditions, this paper presents a new control method for a four-wire three-phase unified power quality conditioner (UPQC) which is based on instantaneous power p-q theory. The proposed control approach is based on instantaneous power and is optimized by using a self-tuning filter (STF), without using any low-pass filters (LPFs) or phase locked loop (PLL), and without measuring load or filter currents. In this approach, the load and source voltages are used to generate the reference voltages of a series active power filter (APF) and source currents are used to generate the reference currents of a shunt APF. Therefore, the number of times that current is measured is reduced and system performance is improved. The performance of the proposed control approach is evaluated in terms of power factor correction, source neutral current mitigation, load balancing and mitigation of the current and voltage harmonics of distortional and unbalanced loads in a three-phase four-wire system. The results obtained by MATLAB/SIMULINK software show the effectiveness of the proposed control technique in comparison to the conventional p-q method.U ovom radu prikazana je nova metoda upravljanja za trofazni četverožični UPQC (engl. unified power quality conditioner) temeljena na teoriji trenutne vrijednosti snage koja je prikladna za upravljanje tijekom distorzijskih i nesimetričnih uvjeta na teretu. Predloženo upravljanje temelji se na teoriji o trenutnoj radnoj i jalovoj snazi i optimirano je korištenjem samopodešavajućeg fitera, bez korištenja niskopropusnih filtera ili PLL-a i bez mjerenja struje tereta i filtra. Korišteni su naponi na teretu i napon izvora kako bi se generirala referentna vrijednost napona aktivnog filtra, a struje izvora koriste se za generiranje referentne vrijednosti struje aktivnog filtra. Na taj način smanjen je broj mjerenja struje i sustav ima bolje značajke. Uz predloženi sustav upravljanja testire su mogućnosti korekcije faktora snage, smanjenja neutralne struje izvora, balansiranja tereta, smanjenje harmonika u struji i naponu. Rezultati dobiveni pomoću MATLAB/SIMULINK-a pokazuju učinkovitost predloženog sustava upravljanja

Modelling and Verification of a Cluster-tree Formation Protocol Implementation for the IEEE 802.15.4 TSCH MAC Operation Mode

Correct and efficient initialization of wireless sensor networks can be challenging in the face of many uncertainties present in ad hoc wireless networks. In this paper we examine an implementation for the formation of a cluster-tree topology in a network which operates on top of the TSCH MAC operation mode of the IEEE 802.15.4 standard, and investigate it using formal methods. We show how both the mCRL2 language and toolset help us in identifying scenarios where the implementation does not form a proper topology. More importantly, our analysis leads to the conclusion that the cluster-tree formation algorithm has a super linear time complexity. So, it does not scale to large networks

Histopathologic effects of Carthamus tinctorius on the brain liver and kidney of the new born mice

زمینه و هدف: گل های گیاه گلرنگ (Carthamus tinctorius L.) جهت تهیه رنگ و طعم در صنایع غذایی مورد استفاده قرار می‌گیرند، ولی عوارض آن در دوران شیردهی بر نوزاد مشخص نشده است. این مطالعه به منظور بررسی اثرات احتمالی مصرف این گیاه در دوران شیردهی بر روی بافت های مغز، کبد و کلیه نوزادان موش سوری انجام شده است. روش بررسی: در این مطالعه تجربی 32 سر موش ماده آبستن، از نژاد سوری بطور تصادفی به 4 گروه 8 تایی تقسیم شدند. پس از زایمان به گروه 1 (گروه شاهد)، سرم فیزیولو‍ژی و به گروه های 2 تا 4 عصاره متانولی گلرنگ به طور روزانه و به مدت 25 روز (تا پایان دوره شیر دهی) به ترتیب با دوزهای10،20 و 40 میلی گرم به ازای هر کیلوگرم وزن بدن و به صورت داخل صفاقی تزریق شد. مقادیر پارامترهای هماتولو‍ژیک نوزادان در پایان دوره آزمایش مورد سنجش قرار گرفت. نمونه های بافتی کبد، کلیه و مغز نوزادان نر پس از رنگ آمیزی با هماتوکسیلین و ائوزین از نظر آسیب شناسی مورد مطالعه قرار گرفتند. داده ها پس از اطمینان از نرمال بودن به کمک آزمون های آماری ANOVA و شفه تجزیه و تحلیل شدند. یافته ها: عصاره گلرنگ اختلاف معنی داری در تعداد گلبول های سفید، قرمز، هموگلوبین و هماتوکریت گروه های تیمار با گروه شاهد نشان نداد. در آسیب شناسی بافتی بر خلاف گروه کنترل در کلیه ها، کبد و مغز موش های نوزاد تیمار شده با عصاره آسیب های ملایم تا شدیدی مشاهده شد. نتیجه گیری: نتایج بررسی حاضر نشان داد که مصرف عصاره گل گلرنگ در مادران شیرده، برای نوزادان سمی بوده و باعث ایجاد آسیب هایی در بافت های کبد، کلیه و همچنین مغز می شود. لذا بهتر است از مصرف آن در دوره شیردهی خودداری گردد

The Relationship of the Process of Reading in EGP with the Process of Reading in ESP and the Product of Reading in EGP and ESP (Hubungan antara Proses Membaca dalam EGP dengan Proses Membaca dalam ESP dan Hasilan Membaca dalam EGP dan ESP)

ABSTRACT This study using ex post facto design had two purposes. First, it attempted to fi nd out if there was any relationship between the process of reading in EGP (English for General Purposes) and ESP (English for Specicfi c Purpose

Safety Profile of Carthamus Tinctorius L. in Lactation: Brain, Renal and Hepatotoxicity

Background and Objective: Safflower (Carthamus tinctorius L.) is used as dye and flavor in food industry. However, its effects on the infant during lactation has not been yet determined. The present study was conducted with the aim of investigating the possible effects of taking this herb during lactation on brain, liver, kidney and hematologic parameters of newborn mice. Methodology: In this experimental study, 32 pregnant Balb/C mice were randomly divided into four groups of 8. Following the delivery, group 1 (control group) received normal saline injection, and group 2 to 4 received daily intraperitoneal injection of 10, 20 and 40mg/kg methanolic safflower extract for 25 days (until the end of lactation period), respectively. The newborns' hematological parameters were assessed at the end of the study period. Liver, kidney and brain tissue samples of male newborns were histopathologically studied after staining with Hematoxylin & Eosin. Data were analyzed using ANOVA and Scheffe's tests. Results: Use of safflower did not cause any significant difference in the number of White Blood Cells, Red Blood Cells, Hemoglobin and Hematocrit in treatment group in comparison with the control group. In histopathological study, mild to severe injuries were observed in kidney, liver and brain tissues of newborn mice treated with the extract. Conclusions: The results of the present study revealed that taking Safflower extract during lactation period may be toxic for infants and cause some damage in the liver, kidney and brain tissue. Therefore, it is better for lactating mothers to refrain from its use

Age-specific functional response of Aphidius matricariae and Praon volucre (Hym.: Braconidae) on Aphis gossypii (Hem.: Aphididae)

The cotton aphid, Aphis gossypii Glover is a major pest of greenhouse cucumber in the world. In this study, age specific functional response of Aphidius matricariae Haliday and Praon volucre (Haliday) were investigated on A. gossypii at 25±1°C, 60±5% RH and a photoperiod of 14 L: 10 D h. The results showed that the functional response of A. matricariae was type III during 1st, 2nd, 3rd, 4th and 5th days and type II in 6th day of adult parasitoid lifetime. The type of functional response of P. volucre was type II in whole parasitoid lifetime. The highest b value (0.02±0.003 h-1) and the lowest handling time (Th) (0.70±0.013 h) of A. matricariae were observed in the 1st day of parasitoid lifetime. The maximum attack rate (T/Th) of A. matricariae occurred in the first day of parasitoid lifetime (34.28 nymphs). The maximum searching efficiency of P. volucre was determined in the 2nd and 3rd days (0.03±0.003 and 0.03±0.005 h-1) and the minimum handling time was recorded in the 2nd day (0.97±0.140 h) of adult female life. The maximum parasitism rate was 24.74 nymphs in the two day old female, and then decreased in adult female age. The results suggest that A. matricariae and P. volucre are highly effective biological agents in suppressing A. gosspii population on cucumber in greenhouses

The Mean Drift: Tailoring the Mean Field Theory of Markov Processes for Real-World Applications

The statement of the mean field approximation theorem in the mean field theory of Markov processes particularly targets the behaviour of population processes with an unbounded number of agents. However, in most real-world engineering applications one faces the problem of analysing middle-sized systems in which the number of agents is bounded. In this paper we build on previous work in this area and introduce the mean drift. We present the concept of population processes and the conditions under which the approximation theorems apply, and then show how the mean drift is derived through a systematic application of the propagation of chaos. We then use the mean drift to construct a new set of ordinary differential equations which address the analysis of population processes with an arbitrary size