A Congestion Detection Algorithm to Improve Delivery Ratio in the Clustered Wireless Sensor Networks

Juniven Isin D. Sasi,Hyunho Yang 한국정보통신학회 2014 2016 INTERNATIONAL CONFERENCE Vol.6 No.1

Recent studies are being conducted regarding the use of clustering protocols to improve the usability and effectiveness of wireless sensor networks (WSN). But clustering protocols are highly congested, low delivery rate ratio, and traffic in the network is high which can result to perform poorly with its duty. Duplicate packets may also occur that can cause packet collision. In clustering, nodes that are near the sink tend to receive all the packets which creates a bottleneck in the transmission process. In this paper, we propose an improvement in clustering protocols for the recent research studies. Cluster head (CH) was provided a module to check and monitor congestion and traffic status within the cluster network. This notifies the system that congestion occurs to the network and the cluster head’s duty is to update the member nodes in its cluster. In addition, sensor nodes are embedded with a dynamic calculation of transmission rate in its model. This aims to lessen congestion, minimize delay, and improve network delivery rate.

Symptoms-Based Power-Efficient Communication Scheme in WBSN

Sasi, Juniven Isin D.,Yang, Hyunho THE KOREAN INSTITUTE OF SMART MEDIA 2014 스마트미디어저널 Vol.3 No.1

It is practical nowadays to automate data recording in order to prevent loss and tampering of records. There are existing technologies that satisfy this needs and one of them is wireless sensor networks (WSN). Wireless body sensor networks (WBSN) are wireless networks and information-processing systems which are deployed to monitor medical condition of patients. In terms of performance, WBSNs are restricted by energy, and communication between nodes. In this paper, we focused in improving the performance of communication to achieve less energy consumption and to save power. The main idea of this paper is to prioritize nodes that exhibit a sudden change of vital signs that could put the patient at risk. Cluster head is the main focus of this study in order to be effective; its main role is to check the sent data of the patient that exceeds threshold then transfer to the sink node. The proposed scheme implemented added a time-based protocol to sleep/wakeup mechanism for the sensor nodes. We seek to achieve a low energy consumption and significant throughput in this study.

Kinetic deuterium isotope effects for 7-alkoxycoumarin <i>O</i>-dealkylation reactions catalyzed by human cytochromes P450 and in liver microsomes

Kim, Keon-Hee,Isin, Emre M.,Yun, Chul-Ho,Kim, Dong-Hyun,Guengerich, F. BLACKWELL 2006 FEBS JOURNAL Vol.273 No.10

<P>7-Ethoxy (OEt) coumarin has been used as a model substrate in many cytochrome P450 (P450) studies, including the use of kinetic isotope effects to probe facets of P450 kinetics. P450s 1A2 and 2E1 are known to be the major catalysts of 7-OEt coumarin <I>O</I>-deethylation in human liver microsomes. Human P450 1A2 also catalyzed 3-hydroxylation of 7-methoxy (OMe) coumarin at appreciable rates but P450 2E1 did not. Intramolecular kinetic isotope effects were used as estimates of the intrinsic kinetic deuterium isotope effects for both 7-OMe and 7-OEt coumarin dealkylation reactions. The apparent intrinsic isotope effect for P450 1A2 (9.4 for <I>O</I>-demethylation, 6.1 for <I>O</I>-deethylation) showed little attenuation in other competitive and noncompetitive experiments. With P450 2E1, the intrinsic isotope effect (9.6 for <I>O</I>-demethylation, 6.1 for <I>O</I>-deethylation) was attenuated in the noncompetitive intermolecular experiments. High noncompetitive intermolecular kinetic isotope effects were seen for 7-OEt coumarin <I>O</I>-deethylation in a baculovirus-based microsomal system and five samples of human liver microsomes (7.3–8.1 for <I>O</I>-deethylation), consistent with the view that P450 1A2 is the most efficient P450 catalyzing this reaction in human liver microsomes and indicating that the C-H bond-breaking step makes a major contribution to the rate of this P450 (1A2) reaction. Thus, the rate-limiting step appears to be the chemistry of the breaking of this bond by the activated iron-oxygen complex, as opposed to steps involved in the generation of the reactive complex. The conclusion about the rate-limiting step applies to all of the systems studied with this model P450 1A2 reaction including human liver microsomes, the most physiologically relevant.</P>

Determination of collapse safety of shear wall-frame structures

Emel Yükseli Cengiz,Ahmet Isin Saygun 국제구조공학회 2007 Structural Engineering and Mechanics, An Int'l Jou Vol.27 No.2

A new finite shear wall element model and a method for calculation of 3D multi-storied only shear walled or shear walled – framed structures using finite shear wall elements assumed ideal elasto –plastic material are developed. The collapse load of the system subjected to factored constant gravity loads and proportionally increasing lateral loads is calculated with a method of load increments. The shape functions over the element are determined as a cubic variation along the story height and a linear variation in horizontal direction because of the rigid behavior of the floor slab. In case shear walls are chosen as only one element in every floor, correct solutions are obtained by using this developed element. Because of the rigid behavior of the floor slabs, the number of unknowns are reduced substantially. While in framed structures, classical plastic hinge hypothesis is used, in nodes of shear wall elements when vertical deformation parameter is exceeded εe, this node is accepted as a plastic node. While the system is calculated with matrix displacement method, for determination of collapse safety, plastic displacements and plastic deformations are taken as additional unknowns. Rows and columns are added to the system stiffness matrix for additional unknowns.

NUMERICAL INVESTIGATION ON OIL PAN DESIGN PARAMETERS TO IMPROVE ENGINE PERFORMANCE DURING OIL COOL DOWN AND WARM UP PERIODS

Yusuf Kartal,Ovun Isin 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.3

For developing automotive industry, one of the focusing point is reduction of engine friction level to decrease both engine emissions and fuel consumption. Important part of researchers have focused on cold engine start period, which has higher friction loses. Shorter warm up period and faster heating of engine oil help to provide better engine performance. Not only warm up time but also better cool down period after engine stops, dramatically effects engine efficiency. If oil temperature stays hot for longer time during the vehicle key-off duration, it brings an important advantageous at the next start. Main purpose of this study is to investigate oil temperature changes depending on the design parameters of the oil pan. This investigation is done for oil warm up and cool down periods by mathematical model, which is validated for 2.0 L and 4 cylinders diesel engine. Design improvement combinations against base steel oil pan has been examined throughly in terms of oil temperature changes, warm up and cool down time, frictional loses and weight reduction opportunity. As a result, 5 mm thickness plastic oil pan with windage tray application is the best solution option since it brings both 12.5 % friction decreasing in cold start after 2 hours key-off duration, and 43 % weight reduction.

Economic Crisis and Managers' Behavior: Planned Behavioral Theory Approach

Gokhan Cinar,Ferruh Isin,Adnan Hushmat 한국유통과학회 2016 KODISA ICBE (International Conference on Business Vol.2016 No.-

The purpose of this study is to put forward the behavioral trends of the trading firms in the face of economic crisis. A questionnaire study is conducted to 167 firms and their behavioral aspects in crisis period is modeled using planned behavioral theory. The empirical analysis is conducted using Structural Equation Models (SEM). The findings show that the subjective norms and perceptions effect self-confidence and decisions. The results may help in taking necessary measures for operational continuity of the firms in a more rational environment.

Acute Lymphoblastic Leukemia Associated with Brucellosis in Two Patients with Fever and Pancytopenia

Bulent Eser,Fevzi Altuntas,Isin Soyuer,Ozlem Er,Ozlem Canoz,Hasan Senol Coskun,Mustafa Cetin,Ali Unal 연세대학교의과대학 2006 Yonsei medical journal Vol.47 No.5

Brucellosis is a disease involving the lymphoproliferative system, which may lead to changes in the hematological parameters; however, pancytopenia is a rare finding. However, malignant diseases in association with brucellosis are rarely the cause of pancytopenia. Herein, two cases with fever and pancytopenia, diagnosed as simultaneous acute lymphoblastic leukemia and brucellosis are presented. Anti-leukemic therapy and brucellosis treatment were administered simultaneously, and normal blood parameters obtained. The first patient is in complete remission; the other recovered from the brucellosis, but later died due to a leukemic relapse.

How Managers React to Crisis?: A Planned Behavior Theory Approach

Gokhan Cinar,Ferruh Isin,Adnan Hushmat 한국유통과학회 2016 Asian Journal of Business Environment (AJBE) Vol.6 No.4

Purpose - Not all firms are able to completely eliminate the risk arising out of the crisis. Success hides in the ability to perceive the market expectations accurately and take correct decisions. This study aims to analyze the firms’ decisions at gross-root level. Research Design, Data, and Methodology - Primary data is obtained with the help of specially designed questionnaires from the agriproducts export firms that are members of export union of Turkey. The study is based on four theoretical structures: general planned behavior theory model, perception-leading behavior control and subjective norm model, perceived-behavioralcontrol leading perception and subjective norm models, and perceptions and subjective norms leading behavior control model. Structural Equation Models (SEM) is used to conduct the empirical analysis. Results - The findings show perceptions and subjective norms leading behavior control model as the best one, concluding that the environmental pressures and positive perceptions have significant effect on the strategic decisions of the agriproducts export firms. Conclusion - Policy tools like creating positive perception in the markets, providing sufficient information and financial support to the firms and increasing market competition can be used effectively to achieve the said objective.

Determination of collapse safety of shear wall-frame structures

Cengiz, Emel Yukselis,Saygun, Ahmet Isin Techno-Press 2007 Structural Engineering and Mechanics, An Int'l Jou Vol.27 No.2

A new finite shear wall element model and a method for calculation of 3D multi-storied only shear walled or shear walled - framed structures using finite shear wall elements assumed ideal elasto - plastic material are developed. The collapse load of the system subjected to factored constant gravity loads and proportionally increasing lateral loads is calculated with a method of load increments. The shape functions over the element are determined as a cubic variation along the story height and a linear variation in horizontal direction because of the rigid behavior of the floor slab. In case shear walls are chosen as only one element in every floor, correct solutions are obtained by using this developed element. Because of the rigid behavior of the floor slabs, the number of unknowns are reduced substantially. While in framed structures, classical plastic hinge hypothesis is used, in nodes of shear wall elements when vertical deformation parameter is exceeded ${\varepsilon}_e$, this node is accepted as a plastic node. While the system is calculated with matrix displacement method, for determination of collapse safety, plastic displacements and plastic deformations are taken as additional unknowns. Rows and columns are added to the system stiffness matrix for additional unknowns.

Early and Late Complications after Inguinofemoral Lymphadenectomy for Vulvar Cancer

Cirik, Derya Akdag,Karalok, Alper,Ureyen, Isin,Tasci, Tolga,Kalyoncu, Rukiye,Turkmen, Osman,Kose, M Faruk,Tulunay, Gokhan,Turan, Taner Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.13

Background: We aimed to determine the frequency of early and late complications following groin surgery for vulvar cancer and analyze possible risk factors. Materials and Methods: This retrospective cohort study included 99 women who underwent for vulvar cancer. The early (${\leq}1$ month) complications were wound infection, breakdown and lymphocyst and late (>1 month) complications were lower limb lymphedema, incontinence and erysipelas. The risk factors for developing each of the complications were analyzed with regression analysis. Results: In the entire cohort, 29 (29.3%) women experienced early and 12 (12.1%) had late complications. Wound complications including infection and breakdown were the leading early complications (23.2%). In the multivariate analysis, both obesity (body mass index ${\geq}30kg/m^2$) and advanced age (${\geq}65years$) were found as independent predictive factors for early complications. Obese women of advanced age had 6.32 times more risk of experiencing any of the early complications, when compared to non-obese and young women (55.6% vs 8.7%). The most common late complication was lower limb lymphedema (10.1%) that was more frequently seen in young women. However, neither age nor lymph node count were significantly associated with the occurrence of lower limb lymphedema. Conclusions: More than 40% of the women suffered from postoperative complications after inguinofemoral lymphadenectomy in the current study. While advanced age and obesity were the significant predictors for any of the early complications, there was no identified risk factor for lower limb lymphedema.