Human Activity Recognition in Smart Homes Based on a Difference of Convex Programming Problem

( Vahid Ghasemi ),( Ali A. Pouyan ),( Mohsen Sharifi ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.1

Smart homes are the new generation of homes where pervasive computing is employed to make the lives of the residents more convenient. Human activity recognition (HAR) is a fundamental task in these environments. Since critical decisions will be made based on HAR results, accurate recognition of human activities with low uncertainty is of crucial importance. In this paper, a novel HAR method based on a difference of convex programming (DCP) problem is represented, which manages to handle uncertainty. For this purpose, given an input sensor data stream, a primary belief in each activity is calculated for the sensor events. Since the primary beliefs are calculated based on some abstractions, they naturally bear an amount of uncertainty. To mitigate the effect of the uncertainty, a DCP problem is defined and solved to yield secondary beliefs. In this procedure, the uncertainty stemming from a sensor event is alleviated by its neighboring sensor events in the input stream. The final activity inference is based on the secondary beliefs. The proposed method is evaluated using a well-known and publicly available dataset. It is compared to four HAR schemes, which are based on temporal probabilistic graphical models, and a convex optimization-based HAR procedure, as benchmarks. The proposed method outperforms the benchmarks, having an acceptable accuracy of 82.61%, and an average F-measure of 82.3%.

Effectiveness of Acceptance and Commitment Therapy on Life Expectancy of Female Cancer Patients at Tehran's Dehshpour Institute in 2015

Ghasemi, Farahnaz,Dehghan, Fateme,Farnia, Vahid,Tatari, Faeze,Alikhani, Mostafa Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.8

Background: Acceptance and commitment therapy (ACT) increases the psychological flexibility of people afflicted with cancer, and consequently improves their adaptability. The present research was conducted with the aim of determining the effectiveness of ACT for people afflicted with cancer. Materials and Methods: The present research was of semi-pilot type with a pre-test and post-test plan for the proof group. The demographics of the community were composed of all the women with cancer who were under treatment in Tehran's Dehshpour therapeutic center in 2015. The sample was composed of 24 people who were selected as available and chosen randomly in two groups of test and proof. All the participants responded to Snyder questionnaire in two pre-test and post-test stages, and the test group participated in treatment sessions after conducting the pre-test. Results: After collecting the information, data analysis was conducted in two description and inferential levels. The test results of covariance analysis showed that the two groups' hope was meaningfully different. Hope in the test group, compared to the proof group, increased meaningfully. Conclusions: The results show that the ACT is effective in increasing hope of patients with cancer.

Learning and Leveraging Conventions in the Design of Haptic Shared Control Paradigms for Steering a Ground Vehicle

Vahid Izadi,Amir H. Ghasemi 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.10

The main objective of this paper is to establish a framework to study the co-adaptation between humans and automation systems in a haptic shared control framework. We specifically used this framework to design control transfer strategies between humans and automation systems to resolve a conflict when co-steering a semi-automated ground vehicle. The proposed framework contains three main parts. First, we defined a modular structure to separate partner-specific strategies from task-dependent representations and use this structure to learn different co-adaption strategies. In this structure, we assume the human and automation steering commands can be determined by optimizing cost functions. For each agent, the costs are defined as a combination of a set of hand-coded features and vectors of weights. The hand-coded features can be selected to describe task-dependent representations. On the other hand, the weight distributions over these features can be used as a proxy to determine the partner-specific conventions. Second, to leverage the learned co-adaptation strategies, we developed a map connecting different strategies to the outputs of human-automation interactions by employing a collaborative-competitive game concept. Finally, using the map, we designed an adaptable automation system capable of co-adapting to human driver’s strategies. Specifically, we designed an episode-based policy search using the deep deterministic policy gradients technique to determine the optimal weights vector distribution of automation’s cost function. The simulation results demonstrate that the handover strategies designed based on co-adaption between human and automation systems can successfully resolve a conflict and improve the performance of the human automation teaming.

Quantitative and Semiquantitative Health Risk Assessment of Occupational Exposure to Styrene in a Petrochemical Industry

Moshiran, Vahid Ahmadi,Karimi, Ali,Golbabaei, Farideh,Yarandi, Mohsen Sadeghi,Sajedian, Ali Asghar,Koozekonan, Aysa Ghasemi Occupational Safety and Health Research Institute 2021 Safety and health at work Vol.12 No.3

Background: Styrene is one of the aromatic compounds used in acetonitrile-butadiene-styrene (ABS) producing petrochemicals, which has an impact on health of workers. Therefore, this study aimed to investigate the health risks of styrene emitted from the petrochemical industry in Iran. Methods: Air samples were collected based on NIOSH 1501 method. The samples were analyzed by the Varian-cp3800 gas chromatograph. Finally, risk levels of styrene's health effects on employees were assessed by the quantitative method of the U.S. Environmental Protection Agency (U.S. EPA) and the semiquantitative way by the Singapore Occupational Safety and Health Association. Results: Based on the results, the employees had the highest average exposure to styrene vapors (4.06 × 10^-1mg.(kg - day)^-1) in the polybutadiene latex (PBL) unit. Therefore, the most top predictors of cancer and non-cancer risk were 2.3×10^-4 and 7.26 × 10^-1, respectively. Given that the lowest average exposure (1.5 × 10^-2mg.(kg - day)^-1) was in the dryer unit, the prediction showed a moderate risk of cancer (0.8 × 10^-6) and non-cancer (2.3 × 10^-3) for the employees. The EPA method also predicted that there would be a definite cancer risk in 16% and a probable risk in 76% of exposures. However, according to the semiquantitative approach, the rate of risk was at the "low" level for all staff. The results showed that there was a significant difference (p < 0.05) between the units in exposure and health risk of styrene (p < 0.05). Conclusion: Given the high risk of styrene's health effects, appropriate control measures are required to reduce the exposure level.

Exopolysaccharide from Pantoea sp. BCCS 001 GH isolated from nectarine fruit: production in submerged culture and preliminary physicochemical characterizations

Seyyed Vahid Niknezhad,Mohammad Hossein Morowvat,Ghasem Najafpour Darzi,Aida Iraji,Younes Ghasemi 한국식품과학회 2018 Food Science and Biotechnology Vol.27 No.6

Exopolysaccharide (EPS), as potential microbial base polysaccharide source, has plenty of applications due to its unique physicochemical structure. A Pantoea sp. BCCS 001 GH bacterium with the ability to produce a high amount of EPS was identified by 16S rRNA gene sequencing and biochemical tests. The synthesis of EPS by Pantoea sp. BCCS 001 GH was 13.50 g/L in 48 h when sucrose was used as substrate. The proposed protocol was desirably rapid for massive prodcution of EPS and showed the remarkable impact of sucrose and disodium hydrogen phosphate, peptone, Triton x-100 and 2% (v/v) inoculum size on the yields of EPS production. The EPS was mainly composed of glucose and galactose in a relative molar ration (glucose/galactose) of 85.18:14.82, respectively. The preliminary characterization showed the average molecular- weight of EPS is about 2.522 9 106 Da. The microscopics morphology of polymer was formed irregularly shaped structures.

Haemocytes immunity of rose sawfly, Arge ochropus (Hym.: Argidae) against entomopathogenic nematodes, Steinernema carpocapsae and Heterorhabditis bacteriophora

Hadi Sheykhnejad,Mohammad Ghadamyari,Vahid Ghasemi,Salar Jamali,Javad Karimi 한국응용곤충학회 2014 Journal of Asia-Pacific Entomology Vol.17 No.4

The rose sawfly, Arge ochropus (Gmelin), is one of the most destructive pests attacking rose bushes in northernIran. In the present study, the haemocyte reactions of A. ochropus larvaewere assessed against two entomopathogenicnematodes, Steinernema carpocapsae (Weiser) and Heterorhabditis bacteriophora Poinar. With injection ofinfective juveniles of H. bactriophora into A. ochropus larvae, the total haemocyte count showed alternatingfluctuations at all time intervals. Encapsulation occurred 22 hours post injection (hpi) of H. bacteriophorainfective juveniles into the rose sawfly larvae, while melanization was observed after 24 h. In the case of S. carpocapsae, initial attachment of the haemocytes was detected at 18 hpi and complete encapsulation at24 hpi; no melanization was observed. In general, findings showed strong immune responses of the rose sawflylarvae against H. bacteriophora,while these reactionswere weakened for S. carpocapsae. Therefore, it is concludedthat S. carpocapsae has more ability to overcome the host defence system, and this research provides a newwindow on its potential as a biocontrol agent.