Supplier selection, the process of finding the right suppliers who are able to provide the buyer ... more Supplier selection, the process of finding the right suppliers who are able to provide the buyer with the right quality products and/or services at the right price, at the right time and in the right quantities, is one of the most critical activities for establishing an effective supply chain, and is typically a multi-criteria group decision problem. In many practical situations, there usually exists incomplete and uncertain information, and the decision makers cannot easily express their judgments on the candidates with exact and crisp values. Therefore, in this paper an extended VIKOR method for group decision making with intuitionistic fuzzy numbers is proposed to solve the supplier selection problem under incomplete and uncertain information environment. In other researches in this area, the weights of each decision makers and in many of them the weights of criteria are pre-determined, but these weights have been calculated in this paper by using the decision matrix of each decision maker. Also, normalized Hamming distance is proposed to calculate the distance between intuitionistic fuzzy numbers. Finally, a numerical example for supplier selection is given to clarify the main results developed in this paper.
The convergence of traditional voice-oriented telecommunications networks and data-oriented compu... more The convergence of traditional voice-oriented telecommunications networks and data-oriented computer communications networks is yielding new challenges for building systems equally adept at handling voice and data applications. While there is much discussion about packetized voice over IP networks, a little explored opportunity is the ability to more easily deploy innovative new services based on the Internet's client-server paradigm and the ease with which software agents can be introduced and migrated around the network. We discuss our new architecture for middleware services that more effectively enables the integration of telephone and data application. This horizontally-integrated architecture supports competition between interchangeable service implementations, based upon features, cost, etc. It is characterized by pervasive and seamless access across multiple cascaded networks. We describe our experiences in integrating an Internet-based core with cellular and other access networks, and our analysis of IP performance in this testbed using a graphical multi-layer protocol analysis tool. Based on our architecture, we have developed prototype converged applications for voice-actuated room control and personal "universal in-box" information management.
Mobile ad hoc networks Reliable multicast Adaptive Epidemic Bio-inspired Protocol design and anal... more Mobile ad hoc networks Reliable multicast Adaptive Epidemic Bio-inspired Protocol design and analysis a b s t r a c t An emerging approach to distributed systems exploits the self-organization, autonomy and robustness of biological epidemics. In this article, we propose a novel bio-inspired protocol: EraMobile (Epidemic-based Reliable and Adaptive Multicast for Mobile ad hoc networks). We also present extensive performance analysis results for it. EraMobile supports group applications that require high reliability. The protocol aims to deliver multicast data reliably with minimal network overhead, even under adverse network conditions. With an epidemic-based multicast method, it copes with dynamic and unpredictable topology changes due to mobility. Our epidemic mechanism does not require maintaining any tree-or mesh-like structure for multicasting. It requires neither a global nor a partial view of the network, nor does it require information about neighboring nodes and group members. In addition, it substantially lowers overhead by eliminating redundant data transmissions. Another distinguishing feature is its ability to adapt to varying node densities. This lets it deliver data reliably in both sparse networks (where network connectivity is prone to interruptions) and dense networks (where congestion is likely). We describe the working principles of the protocol and study its performance through comparative and extensive simulations in the ns-2 network simulator.
Cobb method has been shown to be the most reliable technique with a reasonable measurement error ... more Cobb method has been shown to be the most reliable technique with a reasonable measurement error to determine the kyphosis in fresh fractures of young patients. However, measurement errors may be higher for elderly patients as it may be difficult to determine the landmarks due to osteopenia and the degenerative changes. The aim of this study is to investigate the intrinsic error for different techniques used in evaluation of local sagittal plane deformity caused by OVCF. Lateral X-rays of OVCF patients were randomly selected. Patient group was composed of 28 females and 7 males and the mean age was 62.7 (55–75) years. The kyphosis angle and the vertebral body height were analyzed to reveal the severity of sagittal plane deformity. Kyphotic deformity was measured by using four different techniques; and the vertebral body heights (VBH) were measured at three different points. The mean intra-observer agreement interval for kyphosis angle measurement techniques ranged from ±7.1 to ±9.3° while it ranged from ±4.5 to ±6.5 mm for VBH measurement techniques. The mean interobserver agreement interval for kyphosis angle ranged from ±8.2 to ±11.1°, while it was between ±4.5 to ±6.5 mm for vertebral body height measurement techniques. This study revealed that although the intra and interobserver agreement were similar for all techniques, they are still higher than expected. These high intervals for measurement errors should be taken into account when interpreting the results of correction in local sagittal plane deformities of OVCF patients after surgical procedures such as vertebral augmentation techniques.
Journal of Clinical Psychology in Medical Settings, 2010
Posttraumatic Growth (PTG) is accepted as positive transformations that are a product of struggli... more Posttraumatic Growth (PTG) is accepted as positive transformations that are a product of struggling with significant stressors such as chronic illness. A model, conceptualized by Schaefer and Moos (Posttraumatic growth: Positive changes in the aftermath of crisis, pp 99–126, 1998), suggests a relative contribution of environmental and individual resources, perception of the event (PE) and coping in the development of PTG. The aim of the present study was to examine the effect of perceived social support (PSS), PE and coping on PTG. This model was tested in a sample of patients with myocardial infarction (MIP, N = 148) from various hospitals in Turkey. The structural equation analysis of the model revealed that PSS was significantly related to PTG through the effect of coping. While coping was significantly and directly related to PTG, PE was not. The findings are discussed in the context of the theoretical model with suggestions for future research.
In this paper, the concept of multiplicative transitivity of a fuzzy preference relation, as defi... more In this paper, the concept of multiplicative transitivity of a fuzzy preference relation, as defined by Tanino [T. Tanino, Fuzzy preference orderings in group decision-making, Fuzzy Sets and Systems 12 (1984) 117-131], is extended to discover whether an interval fuzzy preference relation is consistent or not, and to derive the priority vector of a consistent interval fuzzy preference relation. We achieve this by introducing the concept of interval multiplicative transitivity of an interval fuzzy preference relation and show that, by solving numerical examples, the test of consistency and the weights derived by the simple formulas based on the interval multiplicative transitivity produce the same results as those of linear programming models proposed by Xu and Chen [Z.S. Xu, J. Chen, Some models for deriving the priority weights from interval fuzzy preference relations, European Journal of Operational Research 184 (2008) 266-280]. In addition, by taking advantage of interval multiplicative transitivity of an interval fuzzy preference relation, we put forward two approaches to estimate missing value(s) of an incomplete interval fuzzy preference relation, and present numerical examples to illustrate these two approaches.
... 2006). Both L. sativus and L. cicera are cultivated in Turkey: A. Karadeniz (&amp... more ... 2006). Both L. sativus and L. cicera are cultivated in Turkey: A. Karadeniz (&) 4 N. Erdog˘an Department of Biology, Science and Art Faculty, Mehmet Akif Ersoy University, 15030 Burdur, Turkey e-mail: akaradeniz@mehmetakif.edu.tr ...
167S PURPOSE: We hypothesize that co-culture of NP cells with ASC will generate a microenvironmen... more 167S PURPOSE: We hypothesize that co-culture of NP cells with ASC will generate a microenvironment in which the NP differentiation capacity of ASC will be exhibited. STUDY DESIGN/SETTING: This was tested in a transwell setting using co-cultures of ASCs and NP cells in micromass and/or monolayer. PATIENT SAMPLE: NP-and ASC cells were obtained from the same scoliosis patients. OUTCOME MEASURES: real-time PCR was performed to quantify the relative expression levels of the markers runx-2, CDMP-2, and aggrecan. METHODS: NP cells were isolated according to Gan et al. (Clin Orthop Rel Res 411, p. 315, 2003), ASCs according to Zuk et al. (Tissue Eng 7, p. 211, 2001). Cells were cultured in DMEM/F12ϩ10% FCS. Co-cultures (passage 1 cells) were performed in 4 groups in transwells: (1) NP and ASC monolayer; (2) NP monolayer, ASC micromass; (3) NP micromass, ASC monolayer; and (4) NP and ASC monolayers at opposite sites of the transwell filter. After 11 days of culture, total RNA was isolated, and real-time PCR was performed to quantify the relative expression levels of cbfa1/runx-2, CDMP-2, and aggrecan (normalized to the 18S gene). RESULTS: We found that in both groups 1 and 2, the NP monolayers induced relatively high expressions in ASC for runx-2 (15.32 and 37.03 arbitrary units (a.u.), respectively) and CDMP-2 (17.5 resp. 232.3 a.u.), but no expression of aggrecan mRNA. However, both in group 3 (ASC monolayer with NP micromass culture) as well as in group 4 (ASC and NP monolayers on opposite sides of the transwell filter) only slightly elevated levels of runx-2 (2.3 and 4.9 a.u.) and CDMP-2 (5.5 and 1.6 a.u) were observed, but now also aggrecan mRNA expression could be demonstrated 1.7 a.u and 2.3 a.u). CONCLUSIONS: Our data indicate that NP cell monolayers induce early chondrogenic differentiation in ASC (relatively high runx-2 / CDMP-2, undetectable aggrecan). By contrast, when NP cells are cultured under micromass conditions or when close contacts between ASC and NP cells exist, induction progresses to later differentiation phases (lowered runx-2 / CDMP-2, upregulation of aggrecan). We conclude that in an appropriate microenvironment, as present in the nucleus, ASC can differentiate towards a NP-like phenotype and hence may enhance regeneration of DDD.
Outcome study to determine the internal consistency, and validity of adapted Turkish version of S... more Outcome study to determine the internal consistency, and validity of adapted Turkish version of Scoliosis Research Society-22 (SRS-22) Instrument. To evaluate the validity and reliability of adapted Turkish Version of SRS-22 questionnaire. The SRS-22 questionnaire is a widely accepted questionnaire to assess the health-related quality of life for scoliotic patients in the United States. However, its adaptation in languages other than the source language is necessary for its multinational use. Translation/retranslation of the English version of the SRS-22 was done, and all steps for cross-cultural adaptation process were performed properly by an expert committee. Later, SRS-22 questionnaires and previously validated Short Form-36 (SF-36) outcome instruments were mailed to 82 patients who had been surgically treated for idiopathic scoliosis. All patients had a minimum of 2 years follow-up. Fifty-four patients (66%) responded to the first set of questionnaires. Forty-seven of the first time respondents returned their second survey. The average age of the 47 patients (12 male, 35 female) was 19.8 years (range, 14-31 years). The two measures of reliability as internal consistency and reproducibility were determined by Cronbach alpha statistics and intraclass correlation coefficient, respectively. Concurrent validity was measured by comparing with an already validated questionnaire (SF-36). Measurement was made using the Pearson correlation coefficient (r). The study demonstrated satisfactory internal consistency with high Cronbach alpha values for the four of the corresponding domains (pain, 0.72; self-image, 0.80; mental health, 0.72; and satisfaction, 0.83). However, the Cronbach alpha value for function/activity domain (0.48) was considerably lower than the original questionnaire. The intraclass correlation coefficient for the same domains was 0.80, 0.82, 0.78, 0.81, and 0.76, respectively, demonstrating a satisfactory test/retest reproducibility. Considering concurrent validity, two domains had excellent correlation (r = 0.75-1), while 9 had good correlation (r = 0.50 to 0.75), and 6 had moderate correlation (r =0.25-0.50). Based on these results, question 18 in the function/activity domain with lower Cronbach alpha value was revised while question 15 was excluded. The revised SRS-22 was given to 30 adolescent idiopathic scoliosis patients not included in the index study. The revision could improve the Cronbach alpha value for function/activity domain from 0.48 to 0.81. This study demonstrated that, if measures are to be used across cultures, the items must not only be translated well linguistically but also must be culturally adapted to maintain the content validity of the instrument at a conceptual level across different cultures. This may necessitate several validation studies to ensure and improve consistency in the content and face validity between source and target versions of a questionnaire due to difficulty in detecting subtle differences in the living habits of different cultures.
Supplier selection, the process of finding the right suppliers who are able to provide the buyer ... more Supplier selection, the process of finding the right suppliers who are able to provide the buyer with the right quality products and/or services at the right price, at the right time and in the right quantities, is one of the most critical activities for establishing an effective supply chain, and is typically a multi-criteria group decision problem. In many practical situations, there usually exists incomplete and uncertain information, and the decision makers cannot easily express their judgments on the candidates with exact and crisp values. Therefore, in this paper an extended VIKOR method for group decision making with intuitionistic fuzzy numbers is proposed to solve the supplier selection problem under incomplete and uncertain information environment. In other researches in this area, the weights of each decision makers and in many of them the weights of criteria are pre-determined, but these weights have been calculated in this paper by using the decision matrix of each decision maker. Also, normalized Hamming distance is proposed to calculate the distance between intuitionistic fuzzy numbers. Finally, a numerical example for supplier selection is given to clarify the main results developed in this paper.
The convergence of traditional voice-oriented telecommunications networks and data-oriented compu... more The convergence of traditional voice-oriented telecommunications networks and data-oriented computer communications networks is yielding new challenges for building systems equally adept at handling voice and data applications. While there is much discussion about packetized voice over IP networks, a little explored opportunity is the ability to more easily deploy innovative new services based on the Internet's client-server paradigm and the ease with which software agents can be introduced and migrated around the network. We discuss our new architecture for middleware services that more effectively enables the integration of telephone and data application. This horizontally-integrated architecture supports competition between interchangeable service implementations, based upon features, cost, etc. It is characterized by pervasive and seamless access across multiple cascaded networks. We describe our experiences in integrating an Internet-based core with cellular and other access networks, and our analysis of IP performance in this testbed using a graphical multi-layer protocol analysis tool. Based on our architecture, we have developed prototype converged applications for voice-actuated room control and personal "universal in-box" information management.
Mobile ad hoc networks Reliable multicast Adaptive Epidemic Bio-inspired Protocol design and anal... more Mobile ad hoc networks Reliable multicast Adaptive Epidemic Bio-inspired Protocol design and analysis a b s t r a c t An emerging approach to distributed systems exploits the self-organization, autonomy and robustness of biological epidemics. In this article, we propose a novel bio-inspired protocol: EraMobile (Epidemic-based Reliable and Adaptive Multicast for Mobile ad hoc networks). We also present extensive performance analysis results for it. EraMobile supports group applications that require high reliability. The protocol aims to deliver multicast data reliably with minimal network overhead, even under adverse network conditions. With an epidemic-based multicast method, it copes with dynamic and unpredictable topology changes due to mobility. Our epidemic mechanism does not require maintaining any tree-or mesh-like structure for multicasting. It requires neither a global nor a partial view of the network, nor does it require information about neighboring nodes and group members. In addition, it substantially lowers overhead by eliminating redundant data transmissions. Another distinguishing feature is its ability to adapt to varying node densities. This lets it deliver data reliably in both sparse networks (where network connectivity is prone to interruptions) and dense networks (where congestion is likely). We describe the working principles of the protocol and study its performance through comparative and extensive simulations in the ns-2 network simulator.
Cobb method has been shown to be the most reliable technique with a reasonable measurement error ... more Cobb method has been shown to be the most reliable technique with a reasonable measurement error to determine the kyphosis in fresh fractures of young patients. However, measurement errors may be higher for elderly patients as it may be difficult to determine the landmarks due to osteopenia and the degenerative changes. The aim of this study is to investigate the intrinsic error for different techniques used in evaluation of local sagittal plane deformity caused by OVCF. Lateral X-rays of OVCF patients were randomly selected. Patient group was composed of 28 females and 7 males and the mean age was 62.7 (55–75) years. The kyphosis angle and the vertebral body height were analyzed to reveal the severity of sagittal plane deformity. Kyphotic deformity was measured by using four different techniques; and the vertebral body heights (VBH) were measured at three different points. The mean intra-observer agreement interval for kyphosis angle measurement techniques ranged from ±7.1 to ±9.3° while it ranged from ±4.5 to ±6.5 mm for VBH measurement techniques. The mean interobserver agreement interval for kyphosis angle ranged from ±8.2 to ±11.1°, while it was between ±4.5 to ±6.5 mm for vertebral body height measurement techniques. This study revealed that although the intra and interobserver agreement were similar for all techniques, they are still higher than expected. These high intervals for measurement errors should be taken into account when interpreting the results of correction in local sagittal plane deformities of OVCF patients after surgical procedures such as vertebral augmentation techniques.
Journal of Clinical Psychology in Medical Settings, 2010
Posttraumatic Growth (PTG) is accepted as positive transformations that are a product of struggli... more Posttraumatic Growth (PTG) is accepted as positive transformations that are a product of struggling with significant stressors such as chronic illness. A model, conceptualized by Schaefer and Moos (Posttraumatic growth: Positive changes in the aftermath of crisis, pp 99–126, 1998), suggests a relative contribution of environmental and individual resources, perception of the event (PE) and coping in the development of PTG. The aim of the present study was to examine the effect of perceived social support (PSS), PE and coping on PTG. This model was tested in a sample of patients with myocardial infarction (MIP, N = 148) from various hospitals in Turkey. The structural equation analysis of the model revealed that PSS was significantly related to PTG through the effect of coping. While coping was significantly and directly related to PTG, PE was not. The findings are discussed in the context of the theoretical model with suggestions for future research.
In this paper, the concept of multiplicative transitivity of a fuzzy preference relation, as defi... more In this paper, the concept of multiplicative transitivity of a fuzzy preference relation, as defined by Tanino [T. Tanino, Fuzzy preference orderings in group decision-making, Fuzzy Sets and Systems 12 (1984) 117-131], is extended to discover whether an interval fuzzy preference relation is consistent or not, and to derive the priority vector of a consistent interval fuzzy preference relation. We achieve this by introducing the concept of interval multiplicative transitivity of an interval fuzzy preference relation and show that, by solving numerical examples, the test of consistency and the weights derived by the simple formulas based on the interval multiplicative transitivity produce the same results as those of linear programming models proposed by Xu and Chen [Z.S. Xu, J. Chen, Some models for deriving the priority weights from interval fuzzy preference relations, European Journal of Operational Research 184 (2008) 266-280]. In addition, by taking advantage of interval multiplicative transitivity of an interval fuzzy preference relation, we put forward two approaches to estimate missing value(s) of an incomplete interval fuzzy preference relation, and present numerical examples to illustrate these two approaches.
... 2006). Both L. sativus and L. cicera are cultivated in Turkey: A. Karadeniz (&amp... more ... 2006). Both L. sativus and L. cicera are cultivated in Turkey: A. Karadeniz (&) 4 N. Erdog˘an Department of Biology, Science and Art Faculty, Mehmet Akif Ersoy University, 15030 Burdur, Turkey e-mail: akaradeniz@mehmetakif.edu.tr ...
167S PURPOSE: We hypothesize that co-culture of NP cells with ASC will generate a microenvironmen... more 167S PURPOSE: We hypothesize that co-culture of NP cells with ASC will generate a microenvironment in which the NP differentiation capacity of ASC will be exhibited. STUDY DESIGN/SETTING: This was tested in a transwell setting using co-cultures of ASCs and NP cells in micromass and/or monolayer. PATIENT SAMPLE: NP-and ASC cells were obtained from the same scoliosis patients. OUTCOME MEASURES: real-time PCR was performed to quantify the relative expression levels of the markers runx-2, CDMP-2, and aggrecan. METHODS: NP cells were isolated according to Gan et al. (Clin Orthop Rel Res 411, p. 315, 2003), ASCs according to Zuk et al. (Tissue Eng 7, p. 211, 2001). Cells were cultured in DMEM/F12ϩ10% FCS. Co-cultures (passage 1 cells) were performed in 4 groups in transwells: (1) NP and ASC monolayer; (2) NP monolayer, ASC micromass; (3) NP micromass, ASC monolayer; and (4) NP and ASC monolayers at opposite sites of the transwell filter. After 11 days of culture, total RNA was isolated, and real-time PCR was performed to quantify the relative expression levels of cbfa1/runx-2, CDMP-2, and aggrecan (normalized to the 18S gene). RESULTS: We found that in both groups 1 and 2, the NP monolayers induced relatively high expressions in ASC for runx-2 (15.32 and 37.03 arbitrary units (a.u.), respectively) and CDMP-2 (17.5 resp. 232.3 a.u.), but no expression of aggrecan mRNA. However, both in group 3 (ASC monolayer with NP micromass culture) as well as in group 4 (ASC and NP monolayers on opposite sides of the transwell filter) only slightly elevated levels of runx-2 (2.3 and 4.9 a.u.) and CDMP-2 (5.5 and 1.6 a.u) were observed, but now also aggrecan mRNA expression could be demonstrated 1.7 a.u and 2.3 a.u). CONCLUSIONS: Our data indicate that NP cell monolayers induce early chondrogenic differentiation in ASC (relatively high runx-2 / CDMP-2, undetectable aggrecan). By contrast, when NP cells are cultured under micromass conditions or when close contacts between ASC and NP cells exist, induction progresses to later differentiation phases (lowered runx-2 / CDMP-2, upregulation of aggrecan). We conclude that in an appropriate microenvironment, as present in the nucleus, ASC can differentiate towards a NP-like phenotype and hence may enhance regeneration of DDD.
Outcome study to determine the internal consistency, and validity of adapted Turkish version of S... more Outcome study to determine the internal consistency, and validity of adapted Turkish version of Scoliosis Research Society-22 (SRS-22) Instrument. To evaluate the validity and reliability of adapted Turkish Version of SRS-22 questionnaire. The SRS-22 questionnaire is a widely accepted questionnaire to assess the health-related quality of life for scoliotic patients in the United States. However, its adaptation in languages other than the source language is necessary for its multinational use. Translation/retranslation of the English version of the SRS-22 was done, and all steps for cross-cultural adaptation process were performed properly by an expert committee. Later, SRS-22 questionnaires and previously validated Short Form-36 (SF-36) outcome instruments were mailed to 82 patients who had been surgically treated for idiopathic scoliosis. All patients had a minimum of 2 years follow-up. Fifty-four patients (66%) responded to the first set of questionnaires. Forty-seven of the first time respondents returned their second survey. The average age of the 47 patients (12 male, 35 female) was 19.8 years (range, 14-31 years). The two measures of reliability as internal consistency and reproducibility were determined by Cronbach alpha statistics and intraclass correlation coefficient, respectively. Concurrent validity was measured by comparing with an already validated questionnaire (SF-36). Measurement was made using the Pearson correlation coefficient (r). The study demonstrated satisfactory internal consistency with high Cronbach alpha values for the four of the corresponding domains (pain, 0.72; self-image, 0.80; mental health, 0.72; and satisfaction, 0.83). However, the Cronbach alpha value for function/activity domain (0.48) was considerably lower than the original questionnaire. The intraclass correlation coefficient for the same domains was 0.80, 0.82, 0.78, 0.81, and 0.76, respectively, demonstrating a satisfactory test/retest reproducibility. Considering concurrent validity, two domains had excellent correlation (r = 0.75-1), while 9 had good correlation (r = 0.50 to 0.75), and 6 had moderate correlation (r =0.25-0.50). Based on these results, question 18 in the function/activity domain with lower Cronbach alpha value was revised while question 15 was excluded. The revised SRS-22 was given to 30 adolescent idiopathic scoliosis patients not included in the index study. The revision could improve the Cronbach alpha value for function/activity domain from 0.48 to 0.81. This study demonstrated that, if measures are to be used across cultures, the items must not only be translated well linguistically but also must be culturally adapted to maintain the content validity of the instrument at a conceptual level across different cultures. This may necessitate several validation studies to ensure and improve consistency in the content and face validity between source and target versions of a questionnaire due to difficulty in detecting subtle differences in the living habits of different cultures.
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