Am Mohamed - Academia.edu (original) (raw)

Papers by Am Mohamed

Ecological Monographs, 1999

Mining frequent trees is very useful in domains like bioinformatics, web mining, mining semistruc... more Mining frequent trees is very useful in domains like bioinformatics, web mining, mining semistructured data, and so on. We formulate the problem of mining (embedded) subtrees in a forest of rooted, labeled, and ordered trees. We present TREEMINER, a novel algorithm to discover all frequent subtrees in a forest, using a new data structure called scope-list. We contrast TREEMINER with

Discovery of association rules is an important problem in database mining. In this paper we prese... more Discovery of association rules is an important problem in database mining. In this paper we present new algorithms for fast association mining, which scan the database only once, addressing the open question whether all the rules can be efficiently extracted in a single database pass. The algorithms use novel itemset clustering techniques to approximate the set of potentially maximal frequent itemsets. The algorithms then make use of efficient lattice traversal techniques to generate the frequent itemsets contained in each cluster. We propose two clustering schemes based on equivalence classes and maximal hypergraph cliques, and study two traversal techniques based on bottom-up and hybrid search. We also use a vertical database layout to cluster related transactions together. Experimental results show improvements of over an order of magnitude compared to previous algorithms.

IEEE Transactions on Geoscience and Remote Sensing, 1985

This is the first paper in a two-part sequence that evaluates the microwave dielectric behavior o... more This is the first paper in a two-part sequence that evaluates the microwave dielectric behavior of soil-water mixtures as a function of water content, temperature, and soil textural composition. Part I presents the results of dielectric constant measurements conducted for five different soil types at frequencies between 1.4 and 18 GHz. Soil texture is shown to have an effect on dielectric behavior over the entire frequency range and is most pronounced at frequencies below 5 GHz. In addition, the dielectric properties of frozen soils suggest that a fraction of the soil water component remains liquid even at temperatures of -240C. The dielectric data as measured at room temperature are summarized at each frequency by polynomial expressions dependent upon both the volumetric moisture content mu and the percentage of sand and clay contained in the soil; separate polynomial expressions are given for the real and imaginary parts of the dielectric constant.

Abstract—We study the Shannon capacity of adaptive trans-mission techniques in conjunction with d... more Abstract—We study the Shannon capacity of adaptive trans-mission techniques in conjunction with diversity combining. This capacity provides an upper bound on spectral efficiency us-ing these techniques. We obtain closed-form solutions for the Rayleigh fading channel ...

Ad Hoc Networks, 2005

Recent advances in wireless sensor networks have led to many new protocols specifically designed ... more Recent advances in wireless sensor networks have led to many new protocols specifically designed for sensor networks where energy awareness is an essential consideration. Most of the attention, however, has been given to the routing protocols since they might differ depending on the application and network architecture. This paper surveys recent routing protocols for sensor networks and presents a classification for the various approaches pursued. The three main categories explored in this paper are data-centric, hierarchical and location-based. Each routing protocol is described and discussed under the appropriate category. Moreover, protocols using contemporary methodologies such as network flow and QoS modeling are also discussed. The paper concludes with open research issues. 2 sensor networks can enable a more civic use of landmines by making them remotely controllable and target-specific in order to prevent harming civilians and animals. Security applications of sensor networks include intrusion detection and criminal hunting.

Journal of Clinical Endocrinology & Metabolism, 1997

We measured arterio-venous differences in concentrations of tumor necrosis factor-alpha (TNF alph... more We measured arterio-venous differences in concentrations of tumor necrosis factor-alpha (TNF alpha) and interleukin-6 (IL-6) across a sc adipose tissue bed in the postabsorptive state in 39 subjects [22 women and 17 men; median age, 36 yr (interquartile range, 26-48 yr); body mass index, 31.8 kg/m2 (range, 22.3- 38.7 kg/m2); percent body fat, 28.7% (range, 17.6-50.7%)]. A subgroup of 8 subjects had arteriovenous differences measured across forearm muscle. Thirty subjects were studied from late morning to early evening; 19 ate a high carbohydrate meal around 1300 h, and 11 continued to fast. We found a greater than 2-fold increase in IL-6 concentrations across the adipose tissue bed [arterial, 2.27 pg/mL (range, 1.42-3.53 pg/mL); venous, 6.71 pg/mL (range, 3.36-9.62 pg/mL); P < 0.001], but not across forearm muscle. Arterial plasma concentrations of IL-6 correlated significantly with body mass index (Spearman's r = 0.48; P < 0.01) and percent body fat (Spearman's r = 0.49; P…

Proceedings of The IEEE, 1998

Page 1. A Unified Approach to the Performance Analysis of Digital Communication over Generalized ... more Page 1. A Unified Approach to the Performance Analysis of Digital Communication over Generalized Fading Channels MARVIN K. SIMON, FELLOW, IEEE, ANDMOHAMED-SLIM ALOUINI, STUDENT MEMBER, IEEE Presented ...

Journal of Continuing Education in The Health Professions, 1986

Automatic Vehicle Identification (AVI) technology can be used to significantly improve the effici... more Automatic Vehicle Identification (AVI) technology can be used to significantly improve the efficiency of lecturer's attendance system by providing the capability of automatic identification and data capture. This technology poses many new challenges on current data management systems. AVI data are time-dependent, dynamically changing, in large volumes, and carry implicit semantics. Radio frequency identification (RFID) data management systems need to effectively support such large scale temporal data created by RFID applications. These systems need to have an explicit temporal data model for RFID data to support tracking and monitoring attendance. In addition, the university needs to have an automatic method to transport data from AVI reader to database. This research proposed a framework for Automatic lecturer's Attendance system using AVI technology. A prototype has been developed to test the framework.

Ecological Monographs, 1999

Mining frequent trees is very useful in domains like bioinformatics, web mining, mining semistruc... more Mining frequent trees is very useful in domains like bioinformatics, web mining, mining semistructured data, and so on. We formulate the problem of mining (embedded) subtrees in a forest of rooted, labeled, and ordered trees. We present TREEMINER, a novel algorithm to discover all frequent subtrees in a forest, using a new data structure called scope-list. We contrast TREEMINER with

Discovery of association rules is an important problem in database mining. In this paper we prese... more Discovery of association rules is an important problem in database mining. In this paper we present new algorithms for fast association mining, which scan the database only once, addressing the open question whether all the rules can be efficiently extracted in a single database pass. The algorithms use novel itemset clustering techniques to approximate the set of potentially maximal frequent itemsets. The algorithms then make use of efficient lattice traversal techniques to generate the frequent itemsets contained in each cluster. We propose two clustering schemes based on equivalence classes and maximal hypergraph cliques, and study two traversal techniques based on bottom-up and hybrid search. We also use a vertical database layout to cluster related transactions together. Experimental results show improvements of over an order of magnitude compared to previous algorithms.

IEEE Transactions on Geoscience and Remote Sensing, 1985

This is the first paper in a two-part sequence that evaluates the microwave dielectric behavior o... more This is the first paper in a two-part sequence that evaluates the microwave dielectric behavior of soil-water mixtures as a function of water content, temperature, and soil textural composition. Part I presents the results of dielectric constant measurements conducted for five different soil types at frequencies between 1.4 and 18 GHz. Soil texture is shown to have an effect on dielectric behavior over the entire frequency range and is most pronounced at frequencies below 5 GHz. In addition, the dielectric properties of frozen soils suggest that a fraction of the soil water component remains liquid even at temperatures of -240C. The dielectric data as measured at room temperature are summarized at each frequency by polynomial expressions dependent upon both the volumetric moisture content mu and the percentage of sand and clay contained in the soil; separate polynomial expressions are given for the real and imaginary parts of the dielectric constant.

Abstract—We study the Shannon capacity of adaptive trans-mission techniques in conjunction with d... more Abstract—We study the Shannon capacity of adaptive trans-mission techniques in conjunction with diversity combining. This capacity provides an upper bound on spectral efficiency us-ing these techniques. We obtain closed-form solutions for the Rayleigh fading channel ...

Ad Hoc Networks, 2005

Recent advances in wireless sensor networks have led to many new protocols specifically designed ... more Recent advances in wireless sensor networks have led to many new protocols specifically designed for sensor networks where energy awareness is an essential consideration. Most of the attention, however, has been given to the routing protocols since they might differ depending on the application and network architecture. This paper surveys recent routing protocols for sensor networks and presents a classification for the various approaches pursued. The three main categories explored in this paper are data-centric, hierarchical and location-based. Each routing protocol is described and discussed under the appropriate category. Moreover, protocols using contemporary methodologies such as network flow and QoS modeling are also discussed. The paper concludes with open research issues. 2 sensor networks can enable a more civic use of landmines by making them remotely controllable and target-specific in order to prevent harming civilians and animals. Security applications of sensor networks include intrusion detection and criminal hunting.

Journal of Clinical Endocrinology & Metabolism, 1997

We measured arterio-venous differences in concentrations of tumor necrosis factor-alpha (TNF alph... more We measured arterio-venous differences in concentrations of tumor necrosis factor-alpha (TNF alpha) and interleukin-6 (IL-6) across a sc adipose tissue bed in the postabsorptive state in 39 subjects [22 women and 17 men; median age, 36 yr (interquartile range, 26-48 yr); body mass index, 31.8 kg/m2 (range, 22.3- 38.7 kg/m2); percent body fat, 28.7% (range, 17.6-50.7%)]. A subgroup of 8 subjects had arteriovenous differences measured across forearm muscle. Thirty subjects were studied from late morning to early evening; 19 ate a high carbohydrate meal around 1300 h, and 11 continued to fast. We found a greater than 2-fold increase in IL-6 concentrations across the adipose tissue bed [arterial, 2.27 pg/mL (range, 1.42-3.53 pg/mL); venous, 6.71 pg/mL (range, 3.36-9.62 pg/mL); P < 0.001], but not across forearm muscle. Arterial plasma concentrations of IL-6 correlated significantly with body mass index (Spearman's r = 0.48; P < 0.01) and percent body fat (Spearman's r = 0.49; P…

Proceedings of The IEEE, 1998

Page 1. A Unified Approach to the Performance Analysis of Digital Communication over Generalized ... more Page 1. A Unified Approach to the Performance Analysis of Digital Communication over Generalized Fading Channels MARVIN K. SIMON, FELLOW, IEEE, ANDMOHAMED-SLIM ALOUINI, STUDENT MEMBER, IEEE Presented ...

Journal of Continuing Education in The Health Professions, 1986

Automatic Vehicle Identification (AVI) technology can be used to significantly improve the effici... more Automatic Vehicle Identification (AVI) technology can be used to significantly improve the efficiency of lecturer's attendance system by providing the capability of automatic identification and data capture. This technology poses many new challenges on current data management systems. AVI data are time-dependent, dynamically changing, in large volumes, and carry implicit semantics. Radio frequency identification (RFID) data management systems need to effectively support such large scale temporal data created by RFID applications. These systems need to have an explicit temporal data model for RFID data to support tracking and monitoring attendance. In addition, the university needs to have an automatic method to transport data from AVI reader to database. This research proposed a framework for Automatic lecturer's Attendance system using AVI technology. A prototype has been developed to test the framework.