A multiple hill climbing approach to software module clustering

Automated software module clustering is important for maintenance of legacy systems written in a 'monolithic format' with inadequate module boundaries. Even where systems were originally designed with suitable module boundaries, structure tends to degrade as the system evolves, making re-modularization worthwhile. This paper focuses upon search-based approaches to the automated module clustering problem, where hitherto, the local search approach of hill climbing has been found to be most successful. In the paper we show that results from a set of multiple hill climbs can be combined to locate good 'building blocks' for subsequent searches. Building blocks are formed by identifying the common features in a selection of best hill climbs. This process reduces the search space, while simultaneously 'hard wiring' parts of the solution. The paper reports the results of an empirical study that show that the multiple hill climbing approach does indeed guide the search to higher peaks in subsequent executions. The paper also investigates the relationship between the improved results and the system size

Characterization of Rate Region in Interference Channels with Constrained Power

In this paper, an $n$-user Gaussian interference channel, where the power of the transmitters are subject to some upper-bounds is studied. We obtain a closed-form expression for the rate region of such a channel based on the Perron-Frobenius theorem. While the boundary of the rate region for the case of unconstrained power is a well-established result, this is the first result for the case of constrained power. We extend this result to the time-varying channels and obtain a closed-form solution for the rate region of such channels.Comment: 21 Pages, The Conference Version is Submitted to IEEE International Symposium on Information Theory (ISIT2007

Optimal Order of Decoding for Max-Min Fairness in KK-User Memoryless Interference Channels

A $K$-user memoryless interference channel is considered where each receiver sequentially decodes the data of a subset of transmitters before it decodes the data of the designated transmitter. Therefore, the data rate of each transmitter depends on (i) the subset of receivers which decode the data of that transmitter, (ii) the decoding order, employed at each of these receivers. In this paper, a greedy algorithm is developed to find the users which are decoded at each receiver and the corresponding decoding order such that the minimum rate of the users is maximized. It is proven that the proposed algorithm is optimal.Comment: 11 Pages, Submitted to IEEE International Symposium on Information Theory(ISIT 2007

Mass Profile of the Infall Region of the Abell 2199 Supercluster

Using a redshift survey of 1323 galaxies (1092 new or remeasured) in a region of 95 square degrees centered on the nearby galaxy cluster Abell 2199, we analyze the supercluster containing A2199, A2197, and an X-ray group. The caustic technique accurately reproduces the true mass profiles of simulated simple superclusters (i.e., superclusters where the virial mass of one cluster is 2-10 times the virial mass of all other clusters in the supercluster). We calculate the masses of the two main components of A2197 (A2197W and A2197E) using archival X-ray observations and demonstrate that the A2199 supercluster is simple and thus that the caustic technique should yield an accurate mass profile. The mass profile is uncertain by ~30% within 3 Mpc/h and by a factor of two within 8 Mpc/h and is one of only a few for a supercluster on such large scales. Independent X-ray mass estimates agree with our results at all radii where they overlap. The mass profile strongly disagrees with an isothermal sphere profile but agrees with profiles suggested by simulations. We discuss the interplay of the supercluster dynamics and the dynamics of the bound subclusters. The agreement between the infall mass profile and other techniques shows that the caustic technique is surprisingly robust for simple superclusters (abridged).Comment: 49 pages, 20 figures, to appear in The Astronomical Journal, version containing high-resolution figures available at http://cfa-www.harvard.edu/~krines/a2199mp.p

Optimal FRP Jacket Placement in RC Frame Structures Towards a Resilient Seismic Design

This paper proposes an optimal plan for seismically retrofitting reinforced concrete (RC) frame structures. In this method, the columns are wrapped by fiber-reinforced polymer (FRP) layers along their plastic hinges. This technique enhances their ductility and increases the resiliency of the structure. Two meta-heuristic algorithms (i.e., genetic algorithm and particle swarm optimization) are adopted for this purpose. The number of FRP layers is assumed to be the design variable. The objective of the optimization procedure was to provide a uniform usage of plastic hinge rotation capacity for all the columns, while minimizing the consumption of the FRP materials. Toward this aim, a single objective function containing penalty terms is introduced. The seismic performance of the case study RC frame was assessed by means of nonlinear pushover analyses, and the capacity of the plastic hinge rotation for FRP-confined columns was evaluated at the life safety performance level. The proposed framework was then applied to a non-ductile low-rise RC frame structure. The optimal retrofit scheme for the frame was determined, and the capacity curve, inter-story drift ratios, and fragility functions were computed and compared with alternative retrofit schemes. The proposed algorithm offers a unique technique for the design of more resilient structures.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Microencapsulation of saffron petal anthocyanins with cress seed gum compared with Arabic gum through freeze drying

In this research, encapsulation efficiency of cress seed gum (CSG) as a native hydrocolloid was compared with Arabic gum (AG) and maltodextrin (dextrose equivalent of 20 (M20), and 7 (M7)) for saffron (Crocus sativus) petal's extract by freeze drying method. Combinations of CSG-M20, AG-M20, and M7-M20 with ratios of 50:50 and M20 alone (100%) were used as wall materials. A mixture of 1:5 (based on dry matter) between core (concentrated anthocyanin extract of saffron petal) and wall materials were freeze dried and stability of encapsulated anthocyanins along with color parameters (a∗, b∗, L∗, C, H° and TCD) of final powders were measured during 10 weeks of storage (at 35 °C as an accelerated method). Total anthocyanins were determined through pH differential method every week. Four prepared formulations of encapsulated powders didn't show any significant differences (P > 0.01) in terms of total anthocyanin content measured immediately after production and after 10 weeks storage. AG-M20 mixture and M20 alone showed the highest and lowest TCD, respectively. The mixture of CSG-M20 in comparison with AG-M20 and M20 had the same protecting effect (P < 0.01) but showed a relatively high TCD (9.33). © 2015 Elsevier Ltd. All rights reserved

Dynamic window secured implicit geographic forwarding for wireless sensor network.

Routing security is a major concerned in Wireless Sensor Network since a large scale of unattended nodes is deployed in ad hoc fashion with no possibility of a global addressing due to a limitation of node's memory and the node have to be self organizing when the systems require a connection with the other nodes. It becomes more challenging when the nodes have to act as the router and tightly constrained on energy and computational capabilities where any existing security mechanisms are not allowed to be fitted directly. These reasons thus increasing vulnerabilities to the network layer particularly and to the whole network, generally. In this paper, a Dynamic Window Secured Implicit Geographic Forwarding (DWSIGF) routing is presented where a dynamic time is used for collection window to collect Clear to Send (CTS) control packet in order to find an appropriate hoping node. The DWIGF is expected to minimize a chance to select an attacker as the hoping node that caused by a blackhole attack that happen because of the CTS rushing attack, which promise a good network performance with high packet delivery ratios

Comparison of Outcomes between Endoscopic and Transcleral Cyclophotocoagulation.

Importance: Traditionally cyclophotocoagulation has been reserved as a treatment of last resort for eyes with advanced stage glaucoma, but increasingly it is offered to eyes with less severe disease. Endoscopic approaches in particular are utilized in increasing numbers of patients despite only a small number of publications on its results. Objective: The purpose of this study was to compare the efficacy and safety of endoscopic and transcleral cyclophotocoagulation (ECP and TCP) procedures in eyes with refractory glaucomas. Design, Setting, and Participants: A chart review was performed on consecutive patients who underwent ECP and TCP at a tertiary ophthalmology care center between January 2000 and December 2010. Cases with fewer than 3 months of follow-up or that had concurrent pressure reducing procedures were excluded. The main outcome measures examined were intraocular pressure (IOP), number of glaucoma medications, best corrected visual acuity (BCVA), additional glaucoma procedure required, and complications. Main Outcomes and Measures: Forty-two eyes (42 patients) that underwent ECP and forty-four eyes (44 patients) that underwent TCP were identified. The TCP group had a statistically higher mean age (71.2 ± 16.7 vs. 58.1 ± 22.9 years, respectively), larger proportion of neovascular glaucoma (40.9% vs. 16.7%), worse initial BCVA (logMAR 2.86 vs. 1.81), and higher preoperative IOP (45.3 vs. 26.6 mmHg) than the ECP group. At 12 months follow-up, the mean IOP difference between groups was not statistically significant, although the change in IOP from baseline to 12 months was greater for the TCP group (p = 0.006). The rates of progression to no light perception (NLP) and phthisis bulbi were significantly higher amongst TCP eyes than ECP eyes (27.2% vs. 4.8%, p = 0.017, and 20.5% vs. 0%, p = 0.003, respectively). Of these eyes that progressed, a majority had neovascular glaucoma (NVG). Corneal decompensation was the most frequent complication following ECP (11.9%). Conclusions and Relevance: In patients with preoperative BCVA of 20/400 or better, overall complication rates (cystoid macular edema, exudative retinal detachment, inflammation, cornea decompensation) were higher after ECP than with TCP. In refractory glaucomas in a real world setting (not a trial), TCP was more frequently used in ischemic eyes. TCP was associated with a higher rate of progression to phthisis bulbi and loss of light perception than ECP. However, ECP was associated with a clinically significant rate of corneal decompensation. These outcomes likely were related to the severity of underlying ocular diseases found in these eyes

The potential and challenges of monitoring-supported energy efficiency improvement strategies in existing buildings

The ongoing EU-supported CAMPUS 21 explores the energy efficiency potential of integrated security, control, and building management software. The main objective of the project is to compare the energy and indoor-environmental performance of a number of existing facilities before and after real or virtual implementation of monitoring-based control improvement measures

Magnetic Resonance Imaging of Optic Nerve Traction During Adduction in Primary Open-Angle Glaucoma With Normal Intraocular Pressure.

PurposeWe used magnetic resonance imaging (MRI) to ascertain effects of optic nerve (ON) traction in adduction, a phenomenon proposed as neuropathic in primary open-angle glaucoma (POAG).MethodsSeventeen patients with POAG and maximal IOP ≤ 20 mm Hg, and 31 controls underwent MRI in central gaze and 20° to 30° abduction and adduction. Optic nerve and sheath area centroids permitted computation of midorbital lengths versus minimum paths.ResultsAverage mean deviation (±SEM) was -8.2 ± 1.2 dB in the 15 patients with POAG having interpretable perimetry. In central gaze, ON path length in POAG was significantly more redundant (104.5 ± 0.4% of geometric minimum) than in controls (102.9 ± 0.4%, P = 2.96 × 10-4). In both groups the ON became significantly straighter in adduction (28.6 ± 0.8° in POAG, 26.8 ± 1.1° in controls) than central gaze and abduction. In adduction, the ON in POAG straightened to 102.0% ± 0.2% of minimum path length versus 104.5% ± 0.4% in central gaze (P = 5.7 × 10-7), compared with controls who straightened to 101.6% ± 0.1% from 102.9% ± 0.3% in central gaze (P = 8.7 × 10-6); and globes retracted 0.73 ± 0.09 mm in POAG, but only 0.07 ± 0.08 mm in controls (P = 8.8 × 10-7). Both effects were confirmed in age-matched controls, and remained significant after correction for significant effects of age and axial globe length (P = 0.005).ConclusionsAlthough tethering and elongation of ON and sheath are normal in adduction, adduction is associated with abnormally great globe retraction in POAG without elevated IOP. Traction in adduction may cause mechanical overloading of the ON head and peripapillary sclera, thus contributing to or resulting from the optic neuropathy of glaucoma independent of IOP