Search results for: optimal control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13230

Search results for: optimal control

8490 A Strategic Partner Evaluation Model for the Project Based Enterprises

Authors: Woosik Jang, Seung H. Han

Abstract:

The optimal partner selection is one of the most important factors to pursue the project’s success. However, in practice, there is a gaps in perception of success depending on the role of the enterprises for the projects. This frequently makes a relations between the partner evaluation results and the project’s final performances, insufficiently. To meet this challenges, this study proposes a strategic partner evaluation model considering the perception gaps between enterprises. A total 3 times of survey was performed; factor selection, perception gap analysis, and case application. After then total 8 factors are extracted from independent sample t-test and Borich model to set-up the evaluation model. Finally, through the case applications, only 16 enterprises are re-evaluated to “Good” grade among the 22 “Good” grade from existing model. On the contrary, 12 enterprises are re-evaluated to “Good” grade among the 19 “Bad” grade from existing model. Consequently, the perception gaps based evaluation model is expected to improve the decision making quality and also enhance the probability of project’s success.

Keywords: partner evaluation model, project based enterprise, decision making, perception gap, project performance

Procedia PDF Downloads 154
8489 Sexual Cognitive Behavioral Therapy: Psychological Performance and Openness to Experience

Authors: Alireza Monzavi Chaleshtari, Mahnaz Aliakbari Dehkordi, Amin Asadi Hieh, Majid Kazemnezhad

Abstract:

This research was conducted with the aim of determining the effectiveness of sexual cognitive behavioral therapy on psychological performance and openness to experience in women. The type of research was experimental in the form of pre-test-post-test. The statistical population of this research was made up of all working and married women with membership in the researcher's Instagram social network who had problems in marital-sexual relationships (N=900). From the statistical community, which includes working and married women who are members of the researcher's Instagram social network who have problems in marital-sexual relationships, there are 30 people including two groups (15 people in the experimental group and 15 people in the control group) as available sampling and selected randomly. They were placed in two experimental and control groups. The anxiety, stress, and depression scale (DASS) and the Costa and McCree personality questionnaire were used to collect data, and the cognitive behavioral therapy protocol of Dr. Mehrnaz Ali Akbari was used for the treatment sessions. To analyze the data, the covariance test was used in the SPSS22 software environment. The results showed that sexual cognitive behavioral therapy has a positive and significant effect on psychological performance and openness to experience in women. Conclusion: It can be concluded that interventions such as cognitive-behavioral sex can be used to treat marital problems.

Keywords: sexual cognitive behavioral therapy, psychological function, openness to experience, women

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8488 The Effect of Computerized Systems of Office Automation on Employees' Productivity Efficiency

Authors: Mohammad Hemmati, Mohammad Taban, Ali Yasini

Abstract:

One of the factors that can play an important role in increasing productivity is the optimal use of information technology, which in this area today has a significant role to play in computer systems of office automation in organizations and companies. Therefore, this research has been conducted with the aim of investigating the effect of the relationship between computerized systems of office automation and the productivity of employees in the municipality of Ilam city. The statistical population of this study was 110 people. Using Cochran formula, the minimum sample size is 78 people. The present research is a descriptive-looking research in terms of the type of objective view. A questionnaire was used to collect data. To assess the reliability of variables, Cornbrash’s alpha coefficient was used, which was equal to 0.85; SPSS19 and Pearson test were used to analyze the data and test the hypothesis of the research. In this research, three hypotheses of the relationship between office automation with efficiency, performance, and effectiveness were investigated. The results showed a direct and positive relationship between the office automation system and the increase in the efficiency, effectiveness, and efficiency of employees, and there was no reason to reject these hypotheses.

Keywords: efficiency, performance, effectiveness, automation

Procedia PDF Downloads 210
8487 Design and Development of Compact 1KW Floating Battery Discharge Regulator

Authors: A. Sreedevi, G. Anantaramu

Abstract:

The present space research organizations are striving towards the development of lighter, smaller, more efficient, low cost, and highly reliable power supply. Switch mode power supplies (SMPS) overcome the demerits of linear power supplies such as low efficiency, difficulties in thermal management, and in boosting the output voltage. Space applications require a constant DC voltage to supply its load. As the load varies, the battery terminal voltage tends to vary accordingly. To avoid this variation in the load terminal voltage, a DC-DC regulator is required. The conventional regulator for space applications is isolated boost topology. The proposed topology uses an interleaved push-pull converter with a current doubler secondary to reduce the EMI issues and increase efficiency. The proposed topology uses a floating technique where the converter derives power from the battery and generates only the voltage that is required to fill the gap between the bus and the battery voltage. The direct voltage sense and current loop provide tight regulation of output and better stability. Converter is designed with 50 kHz switching frequency using UC 1825 PWM controller employing both voltage and peak current mode control. Experimental tests have been carried out on the converter under different input and load conditions to validate the design. The experimental results showed that the efficiency was greater than 91%. Stability analysis is done using venable stability analyzer.

Keywords: push pull converter, current doubler, converter, PWM control

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8486 Application of MALDI-MS to Differentiate SARS-CoV-2 and Non-SARS-CoV-2 Symptomatic Infections in the Early and Late Phases of the Pandemic

Authors: Dmitriy Babenko, Sergey Yegorov, Ilya Korshukov, Aidana Sultanbekova, Valentina Barkhanskaya, Tatiana Bashirova, Yerzhan Zhunusov, Yevgeniya Li, Viktoriya Parakhina, Svetlana Kolesnichenko, Yeldar Baiken, Aruzhan Pralieva, Zhibek Zhumadilova, Matthew S. Miller, Gonzalo H. Hortelano, Anar Turmuhambetova, Antonella E. Chesca, Irina Kadyrova

Abstract:

Introduction: The rapidly evolving COVID-19 pandemic, along with the re-emergence of pathogens causing acute respiratory infections (ARI), has necessitated the development of novel diagnostic tools to differentiate various causes of ARI. MALDI-MS, due to its wide usage and affordability, has been proposed as a potential instrument for diagnosing SARS-CoV-2 versus non-SARS-CoV-2 ARI. The aim of this study was to investigate the potential of MALDI-MS in conjunction with a machine learning model to accurately distinguish between symptomatic infections caused by SARS-CoV-2 and non-SARS-CoV-2 during both the early and later phases of the pandemic. Furthermore, this study aimed to analyze mass spectrometry (MS) data obtained from nasal swabs of healthy individuals. Methods: We gathered mass spectra from 252 samples, comprising 108 SARS-CoV-2-positive samples obtained in 2020 (Covid 2020), 7 SARS-CoV- 2-positive samples obtained in 2023 (Covid 2023), 71 samples from symptomatic individuals without SARS-CoV-2 (Control non-Covid ARVI), and 66 samples from healthy individuals (Control healthy). All the samples were subjected to RT-PCR testing. For data analysis, we employed the caret R package to train and test seven machine-learning algorithms: C5.0, KNN, NB, RF, SVM-L, SVM-R, and XGBoost. We conducted a training process using a five-fold (outer) nested repeated (five times) ten-fold (inner) cross-validation with a randomized stratified splitting approach. Results: In this study, we utilized the Covid 2020 dataset as a case group and the non-Covid ARVI dataset as a control group to train and test various machine learning (ML) models. Among these models, XGBoost and SVM-R demonstrated the highest performance, with accuracy values of 0.97 [0.93, 0.97] and 0.95 [0.95; 0.97], specificity values of 0.86 [0.71; 0.93] and 0.86 [0.79; 0.87], and sensitivity values of 0.984 [0.984; 1.000] and 1.000 [0.968; 1.000], respectively. When examining the Covid 2023 dataset, the Naive Bayes model achieved the highest classification accuracy of 43%, while XGBoost and SVM-R achieved accuracies of 14%. For the healthy control dataset, the accuracy of the models ranged from 0.27 [0.24; 0.32] for k-nearest neighbors to 0.44 [0.41; 0.45] for the Support Vector Machine with a radial basis function kernel. Conclusion: Therefore, ML models trained on MALDI MS of nasopharyngeal swabs obtained from patients with Covid during the initial phase of the pandemic, as well as symptomatic non-Covid individuals, showed excellent classification performance, which aligns with the results of previous studies. However, when applied to swabs from healthy individuals and a limited sample of patients with Covid in the late phase of the pandemic, ML models exhibited lower classification accuracy.

Keywords: SARS-CoV-2, MALDI-TOF MS, ML models, nasopharyngeal swabs, classification

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8485 Anti-Acanthamoeba Activities of Fatty Acid Salts and Fatty Acids

Authors: Manami Masuda, Mariko Era, Takayoshi Kawahara, Takahide Kanyama, Hiroshi Morita

Abstract:

Objectives: Fatty acid salts are a type of anionic surfactant and are produced from fatty acids and alkali. Moreover, fatty acid salts are known to have potent antibacterial activities. Acanthamoeba is ubiquitously distributed in the environment including sea water, fresh water, soil and even from the air. Although generally free-living, Acanthamoeba can be an opportunistic pathogen, which could cause a potentially blinding corneal infection known as Acanthamoeba keratitis. So, in this study, we evaluated the anti-amoeba activity of fatty acid salts and fatty acids to Acanthamoeba castellanii ATCC 30010. Materials and Methods: The antibacterial activity of 9 fatty acid salts (potassium butyrate (C4K), caproate (C6K), caprylate (C8K), caprate (C10K), laurate (C12K), myristate (C14K), oleate (C18:1K), linoleate (C18:2K), linolenate (C18:3K)) tested on cells of Acanthamoeba castellanii ATCC 30010. Fatty acid salts (concentration of 175 mM and pH 10.5) were prepared by mixing the fatty acid with the appropriate amount of KOH. The amoeba suspension mixed with KOH with a pH adjusted solution was used as the control. Fatty acids (concentration of 175 mM) were prepared by mixing the fatty acid with Tween 80 (20 %). The amoeba suspension mixed with Tween 80 (20 %) was used as the control. The anti-amoeba method, the amoeba suspension (3.0 × 104 cells/ml trophozoites) was mixed with the sample of fatty acid potassium (final concentration of 175 mM). Samples were incubated at 30°C, for 10 min, 60 min, and 180 min and then the viability of A. castellanii was evaluated using plankton counting chamber and trypan blue stainings. The minimum inhibitory concentration (MIC) against Acanthamoeba was determined using the two-fold dilution method. The MIC was defined as the minimal anti-amoeba concentration that inhibited visible amoeba growth following incubation (180 min). Results: C8K, C10K, and C12K were the anti-amoeba effect of 4 log-unit (99.99 % growth suppression of A. castellanii) incubated time for 180 min against A. castellanii at 175mM. After the amoeba, the suspension was mixed with C10K or C12K, destroying the cell membrane had been observed. Whereas, the pH adjusted control solution did not exhibit any effect even after 180 min of incubation with A. castellanii. Moreover, C6, C8, and C18:3 were the anti-amoeba effect of 4 log-unit incubated time for 60 min. C4 and C18:2 exhibited a 4-log reduction after 180 min incubation. Furthermore, the minimum inhibitory concentration (MIC) was determined. The MIC of C10K, C12K and C4 were 2.7 mM. These results indicate that C10K, C12K and C4 have high anti-amoeba activity against A. castellanii and suggest C10K, C12K and C4 have great potential for antimi-amoeba agents.

Keywords: Fatty acid salts, anti-amoeba activities, Acanthamoeba, fatty acids

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8484 Impact of Prolonged Sodium Hypochlorite Cleaning on Silicon Carbide Ultrafiltration Membranes Prepared via Low-Pressure Chemical Vapor Deposition

Authors: Asif Jan

Abstract:

Sodium hypochlorite (NaClO) is a common cleaning agent for ultrafiltration (UF) membranes. While its detrimental effects on polymeric membranes are well-documented, its impact on ceramic membranes remains less explored. This study investigates the chemical stability of silicon carbide (SiC) UF membranes prepared using low-pressure chemical vapor deposition (LP-CVD) during prolonged NaClO exposure. SiC UF membranes were fabricated via LP-CVD at two different temperature and pressure conditions. LP-CVD offers the advantage of SiC membrane fabrication at significantly lower temperatures (700-900°C) compared to conventional methods. The membranes were subjected to 200 hours of NaClO aging to assess their resilience. Before and after aging, we evaluated the properties and performance of the SiC UF membranes to identify optimal LP-CVD conditions. Our findings show that SiC UF membranes produced at 860°C via LP-CVD exhibit exceptional resistance to NaClO aging, whereas those prepared at 750°C experience significant deterioration. This highlights the crucial role of precise LP-CVD parameters in ensuring the robustness and long-term performance of SiC membranes in harsh chemical cleaning environments.

Keywords: ceramic membranes, ultrafiltration membranes, wastewater treatment, chemical vapor deposition

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8483 Development of an Integrated Methodology for Fouling Control in Membrane Bioreactors

Authors: Petros Gkotsis, Anastasios Zouboulis, Manasis Mitrakas, Dimitrios Zamboulis, E. Peleka

Abstract:

The most serious drawback in wastewater treatment using membrane bioreactors (MBRs) is membrane fouling which gradually leads to membrane permeability decrease and efficiency deterioration. This work is part of a research project that aims to develop an integrated methodology for membrane fouling control, using specific chemicals which will enhance the coagulation and flocculation of compounds responsible for fouling, hence reducing biofilm formation on the membrane surface and limiting the fouling rate acting as a pre-treatment step. For this purpose, a pilot-scale plant with fully automatic operation achieved by means of programmable logic controller (PLC) has been constructed and tested. The experimental set-up consists of four units: wastewater feed unit, bioreactor, membrane (side-stream) filtration unit and permeate collection unit. Synthetic wastewater was fed as the substrate for the activated sludge. The dissolved oxygen (DO) concentration of the aerobic tank was maintained in the range of 2-3 mg/L during the entire operation by using an aerator below the membrane module. The membranes were operated at a flux of 18 LMH while membrane relaxation steps of 1 min were performed every 10 min. Both commercial and composite coagulants are added in different concentrations in the pilot-scale plant and their effect on the overall performance of the ΜΒR system is presented. Membrane fouling was assessed in terms of TMP, membrane permeability, sludge filterability tests, total resistance and the unified modified fouling index (UMFI). Preliminary tests showed that particular attention should be paid to the addition of the coagulant solution, indicating that pipe flocculation effectively increases hydraulic retention time and leads to voluminous sludge flocs. The most serious drawback in wastewater treatment using MBRs is membrane fouling, which gradually leads to membrane permeability decrease and efficiency deterioration. This results in increased treatment cost, due to high energy consumption and the need for frequent membrane cleaning and replacement. Due to the widespread application of MBR technology over the past few years, it becomes clear that the development of a methodology to mitigate membrane fouling is of paramount importance. The present work aims to develop an integrated technique for membrane fouling control in MBR systems and, thus, contribute to sustainable wastewater treatment.

Keywords: coagulation, membrane bioreactor, membrane fouling, pilot plant

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8482 Fault Tolerant (n,k)-star Power Network Topology for Multi-Agent Communication in Automated Power Distribution Systems

Authors: Ning Gong, Michael Korostelev, Qiangguo Ren, Li Bai, Saroj K. Biswas, Frank Ferrese

Abstract:

This paper investigates the joint effect of the interconnected (n,k)-star network topology and Multi-Agent automated control on restoration and reconfiguration of power systems. With the increasing trend in development in Multi-Agent control technologies applied to power system reconfiguration in presence of faulty components or nodes. Fault tolerance is becoming an important challenge in the design processes of the distributed power system topology. Since the reconfiguration of a power system is performed by agent communication, the (n,k)-star interconnected network topology is studied and modeled in this paper to optimize the process of power reconfiguration. In this paper, we discuss the recently proposed (n,k)-star topology and examine its properties and advantages as compared to the traditional multi-bus power topologies. We design and simulate the topology model for distributed power system test cases. A related lemma based on the fault tolerance and conditional diagnosability properties is presented and proved both theoretically and practically. The conclusion is reached that (n,k)-star topology model has measurable advantages compared to standard bus power systems while exhibiting fault tolerance properties in power restoration, as well as showing efficiency when applied to power system route discovery.

Keywords: (n, k)-star topology, fault tolerance, conditional diagnosability, multi-agent system, automated power system

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8481 Fault Tolerant (n, k)-Star Power Network Topology for Multi-Agent Communication in Automated Power Distribution Systems

Authors: Ning Gong, Michael Korostelev, Qiangguo Ren, Li Bai, Saroj Biswas, Frank Ferrese

Abstract:

This paper investigates the joint effect of the interconnected (n,k)-star network topology and Multi-Agent automated control on restoration and reconfiguration of power systems. With the increasing trend in development in Multi-Agent control technologies applied to power system reconfiguration in presence of faulty components or nodes. Fault tolerance is becoming an important challenge in the design processes of the distributed power system topology. Since the reconfiguration of a power system is performed by agent communication, the (n,k)-star interconnected network topology is studied and modeled in this paper to optimize the process of power reconfiguration. In this paper, we discuss the recently proposed (n,k)-star topology and examine its properties and advantages as compared to the traditional multi-bus power topologies. We design and simulate the topology model for distributed power system test cases. A related lemma based on the fault tolerance and conditional diagnosability properties is presented and proved both theoretically and practically. The conclusion is reached that (n,k)-star topology model has measurable advantages compared to standard bus power systems while exhibiting fault tolerance properties in power restoration, as well as showing efficiency when applied to power system route discovery.

Keywords: (n, k)-star topology, fault tolerance, conditional diagnosability, multi-agent system, automated power system

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8480 Cessna Citation X Performances Improvement by an Adaptive Winglet during the Cruise Flight

Authors: Marine Segui, Simon Bezin, Ruxandra Mihaela Botez

Abstract:

As part of a ‘Morphing-Wing’ idea, this study consists of measuring how a winglet, which is able to change its shape during the flight, is efficient. Conventionally, winglets are fixed-vertical platforms at the wingtips, optimized for a cruise condition that the airplane should use most of the time. However, during a cruise, an airplane flies through a lot of cruise conditions corresponding to altitudes variations from 30,000 to 45,000 ft. The fixed winglets are not optimized for these variations, and consequently, they are supposed to generate some drag, and thus to deteriorate aircraft fuel consumption. This research assumes that it exists a winglet position that reduces the fuel consumption for each cruise condition. In this way, the methodology aims to find these optimal winglet positions, and to further simulate, and thus estimate the fuel consumption of an aircraft wearing this type of adaptive winglet during several cruise conditions. The adaptive winglet is assumed to have degrees of freedom given by the various changes of following surfaces: the tip chord, the sweep and the dihedral angles. Finally, results obtained during cruise simulations are presented in this paper. These results show that an adaptive winglet can reduce, thus improve up to 2.12% the fuel consumption of an aircraft during a cruise.

Keywords: aerodynamic, Cessna, Citation X, optimization, winglet

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8479 Effects of Low Sleep Efficiency and Sleep Deprivation on Driver Physical Fatigue

Authors: Chen-Yu Tsai, Wen-Te Liu, Chen-Chen Lo, Kang Lo, Yin-Tzu Lin

Abstract:

Background: Driving drowsiness related to insufficient or disordered sleep accounts for a major percentage of vehicular accidents. Sleep deprivation is the primary reason related to low sleep efficiency. Nevertheless, the mechanism of sleep deprivation induces driving fatigue to remain unclear. Objective: The objective of this study is to associate the relationship between insufficient sleep efficiency and driving fatigue. Methodologies: The physical condition while driving was obtained from the questionnaires to classify the state of driving fatigue. Sleep efficiency was quantified as the polysomnography (PSG), and the sleep stages were sentenced by the reregistered Technologist during examination in a hospital in New Taipei City (Taiwan). The independent T-test was used to investigate the correlation between sleep efficiency, sleep stages ratio, and driving drowsiness. Results: There were 880 subjects recruited in this study, who had been done polysomnography for evaluating severity for obstructive sleep apnea syndrome (OSAS) as well as completed the driver condition questionnaire. Four-hundred-eighty-four subjects (55%) were classified as fatigue group, and 396 subjects (45%) were served as the control group. The ratio of stage three sleep (N3) (0.032 ± 0.056) in fatigue group were significantly lower than the control group (p < 0.01). The significantly higher value of snoring index (242.14 ± 205.51 /hours) was observed in the fatigue group (p < 0.01). Conclusion: We observe the considerable correlation between deep sleep reduce and driving drowsiness. To avoid drowsy driving, the sleep deprivation, and the snoring events during the sleeping time should be monitored and alleviated.

Keywords: driving drowsiness, sleep deprivation, stage three sleep, snoring index

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8478 Behavior of Square Reinforced-Concrete Columns Strengthened with Carbon Fiber Reinforced Polymers under Eccentric Loading

Authors: Dana J. Abed, Mu'tasim S. Abdel-Jaber, Nasim K. Shatarat

Abstract:

In this paper, an experimental study on twelve square columns was conducted to investigate the influence of cross-sectional size on axial compressive capacity of carbon fiber reinforced polymers (CFRP) wrapped square reinforced concrete (RC) short columns subjected to eccentric loadings. The columns were divided into three groups with three cross sections (200×200×1200, 250×250×1500 and 300×300×1800 mm). Each group was tested under two different eccentricities: 10% and 20% of the width of samples measured from the center of the column cross section. Four columns were developed in each arrangement. Two columns in each category were left unwrapped as control samples, and two were wrapped with one layer CFRP perpendicular to the specimen surface. In general; CFRP sheets has enhanced the performance of the strengthened columns compared to the control columns. It was noticed that the percentage of compressive capacity enhancement was decreased by increasing the cross-sectional size, and increasing loading eccentricity generally leads to reduced load bearing capacity in columns. In the same group specimens, when the eccentricity increased the percentage of enhancement in load carrying capacity was increased. The study concludes that the optimum use of the CFRP sheets for axial strength enhancement is for smaller cross-section columns under higher eccentricities.

Keywords: CFRP, columns, eccentric loading, cross-sectional

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8477 The Effectiveness of Solution-Focused Group Therapy on Improving Depressed Mothers of Child Abuser Families

Authors: Roya Maqami, Kaveh Qaderi Bagajan, Mohammad Mahdi Yousefi, Saeed Moradi

Abstract:

The purpose of this study is to investigate the efficacy of solution-focused group therapy on improving the depressed mothers of child abuser families. This study was carried out in the form of a semi-pilot, pre-test and post-test on two groups (experimental and control). Subjects include all mothers and their children that are the members of Shush and Naser Khosro child home. Beck Depression Inventory and Child Trauma Questionnaire were used to collect data. First, child abuse questionnaire was completed by children, Then Beck Depression Inventory was completed by their mothers that 22 of them were recognized as depressed and randomly divided in two groups of experimental and control. After applying pre-test for both of these groups, the intervention of solution- focused group therapy was performed in five sessions on experimental group. Finally, post-test was applied on both groups and subsequently in a month, follow-up test was performed. T-test, multivariate variance, and repeated measurement analysis of variance were used to analyze the data. According to the findings, it can be concluded that this therapy leads to the improvement of depressed mother's mood. As a result, the intervention of solution-focused group therapy is useful in order to improve the depressing mood of mothers of child abuser families.

Keywords: child abuse, depressed mothers, child abuser families, solution focused group therapy

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8476 A Model for Optimizing Inventory Replenishment and Shelf Space Management in Retail Industries

Authors: Nermine A. Harraz, Aliaa Abouali

Abstract:

The retail stores put up for sale multiple items while the spaces in the backroom and display areas constitute a scarce resource. Availability, volume, and location of the product displayed in the showroom influence the customer’s demand. Managing these operations individually will result in sub-optimal overall retail store’s profit; therefore, a non-linear integer programming model (NLIP) is developed to determine the inventory replenishment and shelf space allocation decisions that together maximize the retailer’s profit under shelf space and backroom storage constraints taking into consideration that the demand rate is positively dependent on the amount and location of items displayed in the showroom. The developed model is solved using LINGO® software. The NLIP model is implemented in a real world case study in a large retail outlet providing a large variety of products. The proposed model is validated and shows logical results when using the experimental data collected from the market.

Keywords: retailing management, inventory replenishment, shelf space allocation, showroom, backroom

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8475 Weighted Rank Regression with Adaptive Penalty Function

Authors: Kang-Mo Jung

Abstract:

The use of regularization for statistical methods has become popular. The least absolute shrinkage and selection operator (LASSO) framework has become the standard tool for sparse regression. However, it is well known that the LASSO is sensitive to outliers or leverage points. We consider a new robust estimation which is composed of the weighted loss function of the pairwise difference of residuals and the adaptive penalty function regulating the tuning parameter for each variable. Rank regression is resistant to regression outliers, but not to leverage points. By adopting a weighted loss function, the proposed method is robust to leverage points of the predictor variable. Furthermore, the adaptive penalty function gives us good statistical properties in variable selection such as oracle property and consistency. We develop an efficient algorithm to compute the proposed estimator using basic functions in program R. We used an optimal tuning parameter based on the Bayesian information criterion (BIC). Numerical simulation shows that the proposed estimator is effective for analyzing real data set and contaminated data.

Keywords: adaptive penalty function, robust penalized regression, variable selection, weighted rank regression

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8474 Rapid Detection of Melamine in Milk Products Based on Modified Gold Electrode

Authors: Rovina Kobun, Shafiquzzaman Siddiquee

Abstract:

A novel and simple electrochemical sensor for the determination of melamine was developed based on modified gold electrode (AuE) with chitosan (CHIT) nanocomposite membrane, zinc oxide nanoparticles (ZnONPs) and ionic liquids ([EMIM][Otf]) to enhance the potential current response of melamine. Cyclic voltammetry and differential pulse voltammetry were used to investigate the electrochemical behaviour between melamine and modified AuE in the presence of methylene blue as a redox indicator. The experimental results indicated that the interaction of melamine with CHIT/ZnONPs/([EMIM][Otf])/AuE were based on the strong interaction of hydrogen bonds. The morphological characterization of modified AuE was observed under scanning electron microscope. Under optimal conditions, the current signal was directly proportional to the melamine concentration ranging from 9.6 x 10-5 to 9.6 x 10-11 M, with a correlation coefficient of 0.9656. The detection limit was 9.6 x 10-12 M. Finally, the proposed method was successfully applied and displayed an excellent sensitivity in the determination of melamine in milk samples.

Keywords: melamine, gold electrode, zinc oxide nanoparticles, cyclic voltammetries, differential pulse voltammetries

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8473 Waste to Biofuel by Torrefaction Technology

Authors: Jyh-Cherng Chen, Yu-Zen Lin, Wei-Zhi Chen

Abstract:

Torrefaction is one of waste to energy (WTE) technologies developing in Taiwan recently, which can reduce the moisture and impurities and increase the energy density of biowaste effectively. To understand the torrefaction characteristics of different biowaste and the influences of different torrefaction conditions, four typical biowaste were selected to carry out the torrefaction experiments. The physical and chemical properties of different biowaste prior to and after torrefaction were analyzed and compared. Experimental results show that the contents of elemental carbon and caloric value of the four biowaste were significantly increased after torrefaction. The increase of combustible and caloric value in bamboo was the greatest among the four biowaste. The caloric value of bamboo can be increased from 1526 kcal/kg to 6104 kcal/kg after 300oC and 1 hour torrefaction. The caloric value of torrefied bamboo was almost four times as the original. The increase of elemental carbon content in wood was the greatest (from 41.03% to 75.24%), and the next was bamboo (from 47.07% to 74.63%). The major parameters which affected the caloric value of torrefied biowaste followed the sequence of biowaste kinds, torrefaction time, and torrefaction temperature. The optimal torrefaction conditions of the experiments were bamboo torrefied at 300oC for 3 hours, and the corresponding caloric value of torrefied bamboo was 5953 kcal/kg. This caloric value is similar to that of brown coal or bituminous coal.

Keywords: torrefaction, waste to energy, calorie, biofuel

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8472 Mapping the Turbulence Intensity and Excess Energy Available to Small Wind Systems over 4 Major UK Cities

Authors: Francis C. Emejeamara, Alison S. Tomlin, James Gooding

Abstract:

Due to the highly turbulent nature of urban air flows, and by virtue of the fact that turbines are likely to be located within the roughness sublayer of the urban boundary layer, proposed urban wind installations are faced with major challenges compared to rural installations. The challenge of operating within turbulent winds can however, be counteracted by the development of suitable gust tracking solutions. In order to assess the cost effectiveness of such controls, a detailed understanding of the urban wind resource, including its turbulent characteristics, is required. Estimating the ambient turbulence and total kinetic energy available at different control response times is essential in evaluating the potential performance of wind systems within the urban environment should effective control solutions be employed. However, high resolution wind measurements within the urban roughness sub-layer are uncommon, and detailed CFD modelling approaches are too computationally expensive to apply routinely on a city wide scale. This paper therefore presents an alternative semi-empirical methodology for estimating the excess energy content (EEC) present in the complex and gusty urban wind. An analytical methodology for predicting the total wind energy available at a potential turbine site is proposed by assessing the relationship between turbulence intensities and EEC, for different control response times. The semi-empirical model is then incorporated with an analytical methodology that was initially developed to predict mean wind speeds at various heights within the built environment based on detailed mapping of its aerodynamic characteristics. Based on the current methodology, additional estimates of turbulence intensities and EEC allow a more complete assessment of the available wind resource. The methodology is applied to 4 UK cities with results showing the potential of mapping turbulence intensities and the total wind energy available at different heights within each city. Considering the effect of ambient turbulence and choice of wind system, the wind resource over neighbourhood regions (of 250 m uniform resolution) and building rooftops within the 4 cities were assessed with results highlighting the promise of mapping potential turbine sites within each city.

Keywords: excess energy content, small-scale wind, turbulence intensity, urban wind energy, wind resource assessment

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8471 Effect of Dietary Inclusion of Moringa oleifera Leaf Meal on Blood Biochemical Changes and Lipid Profile of Vanaraja Chicken in Tropics

Authors: Kaushalendra Kumar, Abhishek Kumar, Chandra Moni, Sanjay Kumar, P. K. Singh, Ajeet Kumar

Abstract:

Present study investigated the dietary inclusion of Moringa oleifera leaf meal (MOLM) on production efficiency, hemato-biochemical profile and economy of Vanaraja birds under tropical condition. Experiment was conducted for a period of 56 days on 300 Vanaraja birds randomly divided in to five different experimental groups including control of 60 birds each group replicated with 20 chicks in each replicate. T1, T2, T3, T4, and T5 were offered with 0, 5, 10, 15, and 20% Moringa oleifera leaf meal along with basal ration. All the standard managemental practices were followed during experimental period including vaccination schedule. Locally available Moringa oleifera leaves were harvested at mature stage and allowed to dry under shady and aerated conditions. Thereafter, dried leaves were milled to make a leaf meal and stored in the airtight nylon bags to avoid any possible contamination from foreign material and use for experiment. Production parameters were calculated based on the amount of feed consumed and weight gain every weeks. The body weight gain of T2 group was significantly (P < 0.05) higher side whereas T3 group was comparable with control. The feed conversion ratio for T2 group was found to be significantly (P < 0.05) lower than all other treatment groups, while none of the group was comparable with each other. At the end of the experiment blood samples were collected from birds for haematology study while serum biochemistry performed using spectrophotometer following statndard protocols. The haematological attributes were significantly (P > 0.05) not differed among the groups. However, serum biochemistry showed significant reduction (P < 0.05) of blood urea nitrogen, uric acid and creatinine level with higher level of MOLM diet, indicates better utilization of protein supplemented through MOLM. The total cholesterol and triglyceride level was declined significantly (P < 0.05) as compare to control group with increased level of MOLM in basal diet, decreasing trend of serum cholesterol noted. However, value of HDL for T3 group was highest and for T1 group was lowest but no significant difference (P < 0.05) found among the groups. It might be due to presence of β-sitosterol a bioactive compound present in MOLM which causes lowering of plasma concentration of LDL. During experiment total, LDL and VLDL level was found to be decreased significantly (P < 0.05) as compare to control group. It was observed that the production efficiency of birds significantly improved with 5% followed by 10% Moringa oleifera leaf meal among the treatment groups. However, the maximum profit per kg live weight was noted in 10 % level and least profit observed in 20% MOLM fed group. It was concluded that the dietary inclusion of MOLM improved overall performances without affecting metabolic status and effective in reducing cholesterol level reflects healthy chicken production for human consumption.

Keywords: hemato biochemistry, Moringa oleifera leaf meal, performance, Vanaraja birds

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8470 Participants’ Perception and a Student Protest of Peking University in 2014

Authors: Ruanzhenghao Shi

Abstract:

Student movements have persisted in mainland China, especially in elite universities since the Tiananmen Prodemocracy Movement, contrary to the lack of studies on them. However, the participants' repertoire, mobilization and mode of interaction with authorities are vastly different from their predecessors in the 1980s as well as their western counterparts. In most of the cases, agents, cognizant of the high cost of action and their vulnerability to the authorities, consciously curtailed certain repertoire and themes of resistance. Thus these movements, without appreciable organized force, were self-interested, fragmentally mobilized, lowly integrated and limited within the campus. This study documents the 2014 protest against Yanching Academy program at Peking University, a top-tier Chinese university that played the leading role in the 1989 protest. The 2014 case is different from abovementioned trend of submissive resistance in the last twenty years, insofar as it is a value-oriented and emotion-driven collective action with the resurgence of some repertoire. The participants perceived the university's contemporary ineffectiveness and clumsiness in control and administration, higher Party authorities' indifference to less-political themes, and an increasing number of potential advocates, including students, intellectuals and social media. It shows that resisters' perception of their relative strength to their opponents - in this case, the university and its system for controlling students - under specific circumstances, not merely political opportunities or institutional changes, stimulates the participants and thus contributes to the mobilization and organization of a collective action, even under severe social control.

Keywords: collective action, China, university students, resistance

Procedia PDF Downloads 147
8469 Applying Cationic Porphyrin Derivative 5, 10-Dihexyl-15, 20bis Porphyrin, as Transfection Reagent for Gene Delivery into Mammalian Cells

Authors: Hajar Hosseini Khorami

Abstract:

Porphyrins are organic, aromatic compounds found in heme, cytochrome, cobalamin, chlorophyll , and many other natural products with essential roles in biological processes that their cationic forms have been used as groups of favorable non-viral vectors recently. Cationic porphyrins are self-chromogenic reagents with a high capacity for modifications, great interaction with DNA and protection of DNA from nuclease during delivery of it into a cell with low toxicity. In order to have high efficient gene transfection into the cell while causing low toxicity, genetically manipulations of the non-viral vector, cationic porphyrin, would be useful. In this study newly modified cationic porphyrin derivative, 5, 10-dihexyl-15, 20bis (N-methyl-4-pyridyl) porphyrin was applied. Cytotoxicity of synthesized cationic porphyrin on Chinese Hamster Ovarian (CHO) cells was evaluated by using MTT assay. This cationic derivative is dose-dependent, with low cytotoxicity at the ranges from 100 μM to 0.01μM. It was uptake by cells at high concentration. Using direct non-viral gene transfection method and different concentration of cationic porphyrin were tested on transfection of CHO cells by applying derived transfection reagent with X-tremeGENE HP DNA as a positive control. However, no transfection observed by porphyrin derivative and the parameters tested except for positive control. Results of this study suggested that applying different protocol, and also trying other concentration of cationic porphyrins and DNA for forming a strong complex would increase the possibility of efficient gene transfection by using cationic porphyrins.

Keywords: cationic porphyrins, gene delivery, non-viral vectors, transfection reagents

Procedia PDF Downloads 192
8468 Heat Treatment of Additively Manufactured Hybrid Rocket Fuel Grains

Authors: Jim J. Catina, Jackee M. Gwynn, Jin S. Kang

Abstract:

Additive manufacturing (AM) for hybrid rocket engines is becoming increasingly attractive due to its ability to create complex grain configurations with improved regression rates when compared to cast grains. However, the presence of microvoids in parts produced through the additive manufacturing method of Fused Deposition Modeling (FDM) results in a lower fuel density and is believed to cause a decrease in regression rate compared to ideal performance. In this experiment, FDM was used to create hybrid rocket fuel grains with a star configuration composed of acrylonitrile butadiene styrene (ABS). Testing was completed to determine the effect of heat treatment as a post-processing method to improve the combustion performance of hybrid rocket fuel grains manufactured by FDM. For control, three ABS star configuration grains were printed using FDM and hot fired using gaseous oxygen (GOX) as the oxidizer. Parameters such as thrust and mass flow rate were measured. Three identical grains were then heat treated to varying degrees and hot fired under the same conditions as the control grains. This paper will quantitatively describe the amount of improvement in engine performance as a result of heat treatment of the AM hybrid fuel grain. Engine performance is measured in this paper by specific impulse, which is determined from the thrust measurements collected in testing.

Keywords: acrylonitrile butadiene styrene, additive manufacturing, fused deposition modeling, heat treatment

Procedia PDF Downloads 113
8467 Workaholism: A Study of Iranian Journalists at Gender, Career, and Educational Diversity

Authors: Minavand Mohammad, Maghsoudi Masoud, Mousavi Mahdis, Vahed Zahra, Hamidi Shabnam

Abstract:

While workaholism in organizations has received considerable popular attention, our understanding of it on the basis of research proof is limited. This comes from the deficiency of both appropriate definitions and measures of the concept. The purpose of this paper is to investigate gender, career and educational diversity in three workaholism components among Iranian journalists. Data were collected from 243 journalists (110 men and 133 women) using nameless completed questionnaires, with a 48 percent response rate. No gender differences found between male and female respondents, so there seems no consistency with previous findings. Furthermore, the results showed that different levels of jobs and education score correspondingly on the measures of work involvement, feeling driven to work and work enjoyment. All data are gathered using self report questionnaires. It is not evident the extent to which these findings would generalize to men and women in other vocations. This investigation has a contribution to the small but growing literature on flow and optimal experience in media organizations in Iran.

Keywords: gender, career, education, workaholism, Iranian journalists, work involvement, work enjoyment, feeling driven to work

Procedia PDF Downloads 381
8466 The Impact of One Session of Kumite Training, Speed Kata and Strength Kata on the Rate of Viscosity, Fibrinogen and Plasma Lipid Profile in Young Karate Player Women

Authors: Miesam Golzadeh Gangraj, Abbas Ganbari Niaki, Lila Bahrami

Abstract:

The main aim of this study is to investigate the effect of one session of Karate training (Kumite, speed Kata and strength Kata) on viscosity, fibrinogen and plasma lipid profile in young Karate player women. To this end, 40 individuals with required condition were selected and randomly placed in four groups. 10 mL forearm venous blood was taken before and immediately after a session of training for measuring variables. Data were analyzed using statistical methods (covariance, by consideration of group factor) and Bonfferoni post hoc test and the significant difference was determined in P ≤ 0.05. The variation of plasma fibrinogen concentration was not meaningful. The variation of plasma viscosity concentration was not meaningful in groups and between groups. The variation of cortisol concentration was meaningful before and after and between control and experimental groups; however, no difference was observed between three experimental groups. The variation of complete cholesterol, neither tri-glyceride nor intense lipoprotein, was meaningful and significant difference was just seen between control and Kumite groups. The results show that despite meaningful changes in fibrinogen levels, plasma viscosity has not been much affected that might be due to lack of variation in other effective variables such as TG, HDL and hematocrit. Based on the results of present study, it seems that the use of speed Kata seems to be more appropriate to increase the performance of Karate player than strength Karate.

Keywords: female karate player, viscosity, fibrinogen, cortisol, lactate di-dehydrogenase

Procedia PDF Downloads 182
8465 Spino-Pelvic Alignment with SpineCor Brace Use in Adolescent Idiopathic Scoliosis

Authors: Reham H. Diab, Amira A. A. Abdallah, Eman A. Embaby

Abstract:

Background: The effectiveness of bracing on preventing spino-pelvic alignment deterioration in idiopathic scoliosis has been extensively studied especially in the frontal plane. Yet, there is lack of knowledge regarding the effect of soft braces on spino-pelvic alignment in the sagittal plane. Achieving harmonious sagittal plane spino-pelvic balance is critical for the preservation of physiologic posture and spinal health. Purpose: This study examined the kyphotic angle, lordotic angle and pelvic inclination in the sagittal plane and trunk imbalance in the frontal plane before and after a six-month rehabilitation period. Methods: Nineteen patients with idiopathic scoliosis participated in the study. They were divided into two groups; experimental and control. The experimental group (group I) used the SpineCor brace in addition to a rehabilitation exercise program while the control group (group II) had the exercise program only. The mean ±SD age, weight and height were 16.89±2.15 vs. 15.3±2.5 years; 59.78±6.85 vs. 62.5±8.33 Kg and 162.78±5.76 vs. 159±5.72 cm for group I vs. group II. Data were collected using for metric Π system. Results: Mixed design MANOVA showed that there were significant (p < 0.05) decreases in all the tested variables after the six-month period compared with “before” in both groups. Moreover, there was a significant decrease in the kyphotic angle in group I compared with group II after the six-month period. Interpretation and conclusion: SpineCor brace is beneficial in reducing spino-pelvic alignment deterioration in both sagittal and frontal planes.

Keywords: adolescent idiopathic scoliosis, SpineCor, spino-pelvic alignment, biomechanics

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8464 Development and Characterization of a Bio-Sourced Composite Material Based on Phase Change Material and Hemp Shives

Authors: Hachmi Toifane, Pierre Tittelein, Anh Dung Tran Le, Laurent Zalewsi

Abstract:

This study introduces a composite material composed of bio-sourced phase-change material (PCM) of plant origin combined with hemp shives, developed in response to environmental challenges in the construction sector. The state of the art emphasizes the low thermal storage capacity of bio-based materials and highlights increasing need for developing sustainable materials that offer optimal thermal, mechanical, and hydric performances. The combining of PCM's thermal properties and hygric properties of hemp shives results in a material that combines lightness, strength, and hygrothermal regulation. Various formulations are being assessed and compared to conventional hemp concrete. Thermal characterization includes the measurements of thermal conductivity and numerical simulations to evaluate the thermal storage capacity. The results indicate that the addition of PCM significantly enhances the material's thermal storage capacity, positioning this one as a promising, eco-friendly solution for sustainable construction and for improving the energy efficiency of buildings.

Keywords: hemp composite, bio-sourced phase change material, thermal storage, hemp shives

Procedia PDF Downloads 39
8463 A Gauge Repeatability and Reproducibility Study for Multivariate Measurement Systems

Authors: Jeh-Nan Pan, Chung-I Li

Abstract:

Measurement system analysis (MSA) plays an important role in helping organizations to improve their product quality. Generally speaking, the gauge repeatability and reproducibility (GRR) study is performed according to the MSA handbook stated in QS9000 standards. Usually, GRR study for assessing the adequacy of gauge variation needs to be conducted prior to the process capability analysis. Traditional MSA only considers a single quality characteristic. With the advent of modern technology, industrial products have become very sophisticated with more than one quality characteristic. Thus, it becomes necessary to perform multivariate GRR analysis for a measurement system when collecting data with multiple responses. In this paper, we take the correlation coefficients among tolerances into account to revise the multivariate precision-to-tolerance (P/T) ratio as proposed by Majeske (2008). We then compare the performance of our revised P/T ratio with that of the existing ratios. The simulation results show that our revised P/T ratio outperforms others in terms of robustness and proximity to the actual value. Moreover, the optimal allocation of several parameters such as the number of quality characteristics (v), sample size of parts (p), number of operators (o) and replicate measurements (r) is discussed using the confidence interval of the revised P/T ratio. Finally, a standard operating procedure (S.O.P.) to perform the GRR study for multivariate measurement systems is proposed based on the research results. Hopefully, it can be served as a useful reference for quality practitioners when conducting such study in industries. Measurement system analysis (MSA) plays an important role in helping organizations to improve their product quality. Generally speaking, the gauge repeatability and reproducibility (GRR) study is performed according to the MSA handbook stated in QS9000 standards. Usually, GRR study for assessing the adequacy of gauge variation needs to be conducted prior to the process capability analysis. Traditional MSA only considers a single quality characteristic. With the advent of modern technology, industrial products have become very sophisticated with more than one quality characteristic. Thus, it becomes necessary to perform multivariate GRR analysis for a measurement system when collecting data with multiple responses. In this paper, we take the correlation coefficients among tolerances into account to revise the multivariate precision-to-tolerance (P/T) ratio as proposed by Majeske (2008). We then compare the performance of our revised P/T ratio with that of the existing ratios. The simulation results show that our revised P/T ratio outperforms others in terms of robustness and proximity to the actual value. Moreover, the optimal allocation of several parameters such as the number of quality characteristics (v), sample size of parts (p), number of operators (o) and replicate measurements (r) is discussed using the confidence interval of the revised P/T ratio. Finally, a standard operating procedure (S.O.P.) to perform the GRR study for multivariate measurement systems is proposed based on the research results. Hopefully, it can be served as a useful reference for quality practitioners when conducting such study in industries.

Keywords: gauge repeatability and reproducibility, multivariate measurement system analysis, precision-to-tolerance ratio, Gauge repeatability

Procedia PDF Downloads 257
8462 Sensitivity of Steindachneridion parahybae Mature Oocytes versus Embryos at Low Temperature

Authors: Tais Silva Lopes, Danilo Caneppele, Elizabeth Romagosa

Abstract:

Surubim-do-Paraíba, Steindachneridion parahybae is a species of South American fish in critical conditions of extinction. Researches have been developed with the objective of conserving the biological material of this species. We evaluated the cooling of mature oocytes in the cryoprotective solutions containing the following alcohols: methanol, Propylene glycol and DMSO, each at concentrations of 1M, 2M and 4M, totaling nine treatments. After being submitted to treatments, the oocytes were maintained for 120 minutes in cooling to -5.52±2.58⁰C. A sample of oocytes was submitted to negative control (NC), kept in 90% L-15 solution, and positive control (PC), fertilized and taken directly to the incubator. Fertilization and hatching rates were evaluated. In order to compare the sensitivity of oocytes to embryos of the same species, the embryos maintained as CP in the previous assay were used in the free-flow stage (about 22 hours post fertilization) and submitted to the same treatments (prepared in distilled water) and also cooled for 120 min. The evaluation was done by the hatch rate. There was no fertilization rate of the oocytes submitted to the cooling with propylene glycol; the other cryoprotectants presented values of at most 3.7% of fertilization (Methanol 1M), and no treatment completed development until hatching. The cooled embryos had a significant percentage of normal larvae in all treatments, but inversely proportional to the increase in the concentration of the alcohols. DMSO 1M was the most promising treatment for embryo cooling, with 41.7% ± 20.2 of normal larvae, while mature oocytes were highly sensitive to cold.

Keywords: cryoconservation, cooling, embryos, freezing, oocytes, south American fish

Procedia PDF Downloads 235
8461 Antihypertensive Effect of Formulated Apium graveolens: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Authors: Maryam Shayani Rad, Seyed Ahmad Mohajeri, Mohsen Mouhebati, Seyed Danial Mousavi

Abstract:

High blood pressure is one of the most important and serious health-threatening because of no symptoms in most people, which can lead to sudden heart attack, heart failure, and stroke. Nowadays, herbal medicine is one of the best and safest strategies for treatment that have no adverse effects. Apium graveolens (celery) can be used as an alternative treatment for many health conditions such as hypertension. Natural compounds reduce blood pressure via different mechanisms in which Apium graveolens extract provides potent calcium channel blocking properties. A randomized, double-blind, placebo-controlled, cross-over clinical trial was done to evaluate the efficacy of formulated Apium graveolens extract with a maximum yield of 3-n-butylphthalide to reduce systolic and diastolic blood pressure in patients with hypertension. 54 hypertensive patients in the range of 20-68 years old were randomly assigned to the treatment group (26 cases) and the placebo control group (26 cases) and were crossed over after washout duration. The treatment group received at least 2 grams of formulated powder in hard capsules orally, before each meal, 2 times daily. The control group received 2 grams of placebo in hard capsules orally, exactly as the same as shape, time, and doses of treatment group. Treatment was administrated in 12 weeks with 4 weeks washout period at the middle of the study, meaning 4 weeks drug consumption for the treatment group, 4 weeks washout and 4 weeks placebo consumption, and vice versa for the placebo control group. The clinical assessment was done 4 times, including at the beginning and ending of the drug and placebo consumption period by 24-hour ambulatory blood pressure monitoring (ABPM) holter, which measured blood pressure every 15 minutes continuously. There was a statistically significant decrease in both systolic blood pressure (SBP) and diastolic blood pressure (DBP) at the end of drug duration compared to baseline. The changes after 4 weeks on average was about 12.34 mm Hg for the SBP (P < 0.005) and 7.83 mm Hg for the DBP (P < 0.005). The results from this clinical trial study showed this Apium graveolens extract formulation in the mentioned dosage had a significant effect on blood pressure-lowering for hypertensive patients.

Keywords: Apium graveolens extract, clinical trial, cross-over, hypertension

Procedia PDF Downloads 208