Modelling network memory servers with parallel processors, break-downs and repairs.

This paper presents an analytical method for the performability evaluation of a previously reported network memory server attached to a local area network. To increase the performance and availability of the proposed system, an additional server is added to the system. Such systems are prone to failures. With this in mind, a mathematical model has been developed to analyse the performability of the proposed system with break-downs and repairs. Mean queue lengths and the probability of job losses for the LAN feeding the network memory server is calculated and presented

On the structure and evolution of planets and their host stars −- effects of various heating mechanisms on the size of giant gas planets

It is already stated in the previous studies that the radius of the giant planets is affected by stellar irradiation. The confirmed relation between radius and incident flux depends on planetary mass intervals. In this study, we show that there is a single relation between radius and irradiated energy per gram per second ($l_-$), for all mass intervals. There is an extra increase in radius of planets if $l_-$ is higher than 1100 times energy received by the Earth ($l_\oplus$). This is likely due to dissociation of molecules. The tidal interaction as a heating mechanism is also considered and found that its maximum effect on the inflation of planets is about 15 per cent. We also compute age and heavy element abundances from the properties of host stars, given in the TEPCat catalogue (Southworth 2011). The metallicity given in the literature is as [Fe/H]. However, the most abundant element is oxygen, and there is a reverse relation between the observed abundances [Fe/H] and [O/Fe]. Therefore, we first compute [O/H] from [Fe/H] by using observed abundances, and then find heavy element abundance from [O/H]. We also develop a new method for age determination. Using the ages we find, we analyse variation of both radius and mass of the planets with respect to time, and estimate the initial mass of the planets from the relation we derive for the first time. According to our results, the highly irradiated gas giants lose 5 per cent of their mass in every 1 Gyr.Comment: 15 pages, 13 figures, 3 tables. Accepted by MNRA

Analyzing the Effects of Display Characteristics and Cognitive Variables on Performance Using Keystroke and Eye Movement Data

Information about how operators use their eyes while interacting with visual displays is often an overlooked aspect of human-computer interaction. Such information is fundamental to assessing the quality of software interfaces and understanding the cognitive processes that underlie operator behavior. Other research evaluating information displays evolved from using reaction time and subjective data as dependent variables to using oculometric measures. In the current research conventional performance measures are coupled with oculometric measures to evaluate the influence display characteristics and cognitive variables have on performance. Twelve subjects used a software program to complete a series of specified tasks. Subjects were asked to search for 36 item from the database in a serial manner. Both keystroke and oculometric data were recorded while the subjects used the software database. Four dependent variables were derived from this data: task time, error rate, dwell time and dwell frequency. The four independent variables were information density, display layout, task complexity, and experience. Out of the four independent variables used in the current research, task complexity, a cognitive variable, clearly had the largest effect on both the time-based measures of performance and the oculometric measures of performance. Task complexity yielded a main effect in the task time data, the error rate data, the dwell time data and the dwell frequency data. Increases in task complexity yielded increases in task time, error rate, dwell time and dwell frequency. The results also showed that local information density had an effect on task time but only when overall density of the software interface was higher. While it was found that information density had a consistent effect on the frequency of dwells these results support other research that shows information density has a limited effect on performance. The display layout variable also had a limited influence on both performance and oculometric measures

Classes of Analytic Functions Defined by a Differential Operator Related to Conic Domains

Let A be the class of functions f(z) = z + ∑ k = 2∞ a k z k analytic in an open unit disc ∆. We use a generalized linear operator closely related to the multiplier transformation to study certain subclasses of A mapping ∆ onto conic domains. Using the principle of the differential subordination and the techniques of convolution, we investigate several properties of these classes, including some inclusion relations and convolution and coefficient bounds. In particular, we get many known and new results as special cases.Нехай A — клас функцій f(z) = z + ∑∞k = 2akzk, аналітичних у відкритому одиничному крузі Δ. До вивчення деяких підкласів A, що відображають Δ на конічні області, застосовано узагальнений лінійний оператор, тісно пов'язаний з перетворенням множення. За допомогою принципу диференціального підпорядкування та техніки згорток вивчено деякі властивості цих класів, що включають деякі співвідношення включення та згорток, а також оцінки для коефіцієнтів. Наприклад, низку відомих та нових результатів отримано як частинні випадки

Evaluation of the relationship between stylohyoid complex morphology and maxillary/mandibular position using cone beam computed tomography

Background: The aim of this study was to examine the morphologic features of the stylohyoid complex (SHC) and its relation to maxillomandibular position using three-dimensional cone beam computed tomography (CBCT) images. Materials and methods: CBCT images from 157 individuals (74 females, 83 males) were analysed in this study. SHC length, width, and sagittal and transverse angles were measured. The subjects were grouped as skeletal class I, II, and III in order to determine the relative positions of the maxilla and mandible in the sagittal plane and as hypodivergent, normodivergent, and hyperdivergent according to the vertical rotation of the mandible in relation to the skull base. Mann-Whitney U and Kruskal-Wallis H tests were used for statistical analysis. Results: Mean SHC length was 23.56 ± 8.05 mm on the right side and 22.0 ± 6.51 mm on the left; mean SHC width was 3.31 ± 1.40 mm on the right and 2.93 ± 1.30 mm on the left. Mean sagittal angle was 27.43 ± 6.75° on the right side, 27.70 ± 6.51° on the left; mean transverse angle was 70.39 ± 4.59° on the right side and 71.79 ± 4.99° on the left. The only significant difference based on skeletal classification was greater SHC length among males compared to females in the class III group (p < 0.05). Conclusions: No significant relationship was observed between SHC morphology and position of the maxilla or mandible. However, the gender difference observed among class III subjects suggests that SHC morphology may be affected by craniofacial morphology. Maxillofacial surgeons should investigate this anatomical landmark variation before surgical interventions involving this region, such as temporomandibular joint procedures

Anatomical characteristics of the lingual foramen in ancient skulls: a cone beam computed tomography study in an Anatolian population

Background: The purpose of this study is to evaluate the anatomical features of lingual foramina and their bony canals in Anatolian ancient mandibles (9–10th century) by using cone beam computed tomography (CBCT). Materials and methods: Fifty-eight ancient dry mandibles were scanned with CBCT. Lingual foramina were grouped into midline, paramedian, posterior foramina and combination of these groups. Midline group was also classified according to internal surface of the mandible (gonial tubercles [GTs]). The incidence, vertical distance and diameter of lingual foramina were measured according to age groups and gender. Results: The incidence of the lingual foramen was 96.6%. Midline of the symphysis had the highest incidence (34.4%) of foramina (p < 0.05), followed by both midline and paramedian type (32.8%; p < 0.05). Classification in terms of GT represented class 3 as the most encountered group (28.6%). Number of foramina observed in the mandibles ranged from 0 to 6 with the incidence of 3.4% and 32.8%, respectively. The male and < 35 years groups presented larger measurement values in midline region (p < 0.05). Conclusions: Mandibular lingual foramina and bony canals are frequently present in ancient mandibles. When compared with modern subjects, similar findings are observed according to published literatures. CBCT is also proved to be an effective imaging modality in the detection of lingual foramina and canals in anthropological studies

Procjena produktivnosti alternativnih metoda koranja drvnog sortimenta

In Turkey, timber debarking stages are generally carried out by using axes. However, this method takes a lot of time and requires more work forces. In addition, since leaving residual trees with bark in stands increases the risk of insect damages, residual trees require quick barking process. In recent years, chainsaw mounted debarking tools have been widely used in debarking stages due to performing jobs quicker with less labor force. In this study, two different debarking methods including using axes and debarking tool were analyzed by considering operation productivity. The field studies were conducted in Brutian Pine (Pinus brutia Ten.) stand located in Bahçe Forest Enterprise Chief of Osmaniye Forest Enterprise Directorate in Adana Regional Forestry Directorate. As a result of study, the productivity of chainsaw mounted debarking tool was found to be five times higher than that of using axes for debarking. Thus, use of chainsaw mounted debarking tool is better alternative than use of axe in debarking activities, as it takes less time and minimize physical work load of the loggers.U Turskoj se faze koranja drveta obično obavljaju uz pomoć sjekira. Međutim, ta metoda zahtijeva puno vremena i puno radne snage. Uz to, budući da ostavljanje drveta s korom u sastojinama povećava rizik od oštećenja insektima, zahtijeva hitan proces guljenja kore. Posljednjih godina puno se koriste guljači kore koji se montiraju na motornu pilu, budući da se posao obavlja brže s manjim brojem radne snage. U ovoj studiji, analizirane su dvije različite metode koranja u razmatranju produktivnosti rada koje uključuju uporabu sjekira i guljač kore koji se montira na motornu pilu. Terenske studije provedene su u sastojini brucijskog bora (Pinus brutia Ten.) koja se nalazi u Upravi šuma Bahçe u regionalnom šumskom gospodarstvu Adane. Rezultat studije bio je da je produktivnost pila za koranje bila pet puta veća od uporabe sjekira za koranje. Tako je guljač kore koji se montira na motornu pilu bolja alternativa od uporabe sjekire u guljenju kore, budući da je kod njega potrebno manje vremena te smanjuje fizički rad drvosječa

Foramen Scapulae Osseum

We determined that anomaly of foramen scapula osseum on a skeleton of left scapula which has been in Department of Anatomy in Medical Faculty of Dicle University. Incisura scapulae, just medial to the basis of the coracoid process, we observed that the superior transverse scapular ligament ossifies, resulting in a complete osseous passage which is named foramen scapula osseum. A very narrow scapular foramen can produce a complete peripheral compression syndrome of the suprascapular nerve (paresis of supraspinatus and infraspinatus muscles). That variation may an important role for determining in paresis of suprascapular nerve