MODELING AND VALIDATION OF TURBOCHARGED DIESEL ENGINE AIRPATH AND COMBUSTION SYSTEMS

B. UNVER,Y. KOYUNCUOGLU,M. GOKASAN,S. BOGOSYAN 한국자동차공학회 2016 International journal of automotive technology Vol.17 No.1

The ultimate aim of this study is the development of an engine modeling approach that would facilitate the design of model-based control techniques for diesel engines. This will allow for the development of more generalized, modular control strategies for different engine types and sizes as opposed to the commonly practiced map-based engine control strategies that depend on maps and feedforward control and require lengthy modifications every time a change is made. Also, most engine modeling studies focus on either airpath or combustion systems, treating these models and their validation individually, and not as an integrated system as is actually the case. To address the need for more realistic models suitable for model-based control design, this study develops a combined airpath and combustion model for the engine, using analytical models wherever possible and derives a model with appropriate control inputs and outputs that could be used in a control scheme. The inclusion of the actuator dynamics of the Exhaust gas recirculation (EGR), variable geometry turbine (VGT), and Throttle (THR) valves in the airpath model and the consideration of nonlinearities in the combustion model allow for the development of a more thorough engine model, as well as the validation of subsystems and the whole integrated engine model using a complete World Harmonized Transient Cycle (WHTC). This test cycle finds limited use due to its challenging transients, and yet, is the demanded test cycle for emission regulations nowadays. These are unique aspects of this modeling study, the results of which indicate that the developed engine model could be used in control design and hardware-in-the-loop simulation (HILS) based engine control prototyping.

Contents : NGA Transition in Turkey: A Comparative Analysis of LLU and FTTX in An Immature Broadband Market

( M Bilal Unver ),( Mehmet Altunsoy ) 정보통신정책학회 2012 정보통신정책연구 Vol.19 No.2

Turkey is a country with an immature broadband industry. No competitive networks are operative in the broadband market and high-speed access is underdeveloped. The country faces critical regulatory junctures that will have strategic importance for future network growth. Open access regimes such as those of the European countries generally refrain from dictating a specific access model, an approach that is also applied to next-generation networks. In contrast, IP-level bitstream access (BSA) has been the predominant model governing broadband competition in Turkey. As the country is at the crossroads of implementing a framework for next-generation, high-bit rate broadband networks, it faces the question of whether it should imitate the European path by encouraging local loop unbundling (LLU) and other intermediate access policies or whether it should chart a different course that might lead to faster next-generation access (NGA) deployment. To analyse this question, the article reports a quantitative analysis of two possible transition paths from BSA: reliance on copper LLU as an interim step and a more direct and to-the-end route of fibre deployment (FTTX). For each scenario, the pay-back periods and break-even points are calculated. It is concluded that broadband competition requires remedies that facilitate FTTX deployment to tackle the problem of lack of innovation as well as to ensure competitive and faster NGA transition in Turkey. Last but not least, mandatory duct sharing rather than unbundling seems to be the most promising way to sustain and develop NGA competition in Turkey.

Antitumoral Effects of Melissa officinalis on Breast Cancer in Vitro and in Vivo

Saraydin, Serpil Unver,Tuncer, Ersin,Tepe, Bektas,Karadayi, Sule,Ozer, Hatice,Sen, Metin,Karadayi, Kursat,Inan, Deniz,Elagoz, Sahande,Polat, Zubeyde,Duman, Mustafa,Turan, Mustafa Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

Background: There is a long standing interest in the identification of medicinal plants and derived natural products for developing cancer therapeutics. Here we investigated the antiproliferative properties of Melissa officinalis (MO) from Turkey on breast cancer. Methods: MO extracts were studied for cytotoxicity against breast cancer cell lines (MCF-7, MDA-MB-468 and MDA-MB-231). In vitro apoptosis studies were performed by annexin V staining and flow cytometry analyses. Immunohistochemistry for Ki-67 and caspase 7 in the tumoral tissue sections of DMBA-induced mammary tumors in rats was also performed, along with TUNEL assays to detect apoptotic cells. In vivo anticancer activity testing was carried out with reference to inhibition of growth of DMBA induced mammary tumors in rats. Results: MO showed cytotoxicity against three cancer cell lines, inducing increase in Annexin-positive cells. Expression of caspase-7 protein and TUNEL positive cells were much higher in rats treated by MO, compared with the untreated control group, while expression of Ki-67 was decreased. Furthermore, in vivo studies showed that mean tumor volume inhibition ratio in MO treated group was 40% compared with the untreated rats. Conclusion: These results indicated that MO extrcts have antitumoral potential against breast cancer.

Investigation of Supporting Electrolyte Effect on Supercapacitor Properties of Poly(Carbazole) Films

Duran, Berrin,Unver, Irem Cakmakci,Bereket, Gozen The Korean Electrochemical Society 2020 Journal of electrochemical science and technology Vol.11 No.1

In this study poly(carbazole) films deposited on stainless steel have been investigated as electrode material for supercapacitor applications. Poly(carbazole) films were electrodeposited using cyclic voltammetry in presence of lithium, sodium and tetrabutylammonium perchlorate salts. Poly(carbazole) films doped with perchlorate anions having different counter cations were characterized by SEM, ATR-FTIR and solid state conductivity measurements. Capacitive behaviours of PCz coated steel electrodes were tested by cyclic voltammetry, charge-discharge analysis and electrochemical impedance spectroscopy. It was found that counter cation of the dopant is significantly effective on the capacitive performance on the obtained PCz films and the PCz film synthesized from lithium perchlorate has the better capacitive performance than the poly(carbazole)s synthesized from sodium perchlorate and tetrabutylammonium perchlorate salts.

Chemopreventive Effects of Hydatid Disease on Experimental Breast Cancer

Altun, Ahmet,Saraydin, Serpil Unver,Soylu, Sinan,Inan, Deniz Sahin,Yasti, Cinar,Ozdenkaya, Yasar,Koksal, Binnur,Duger, Cevdet,Isbir, Cemil,Turan, Mustafa Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.4

Breast cancer is one of the most common and letal cancers in all over the world. Since there have been significant improvements in treatment of breast cancer, there is still a big need for alternative approaches. In this study, we aimed to investigate protective role of hydatid disease against breast cancer. Twenty Wistar rats were divided into two groups of 10 rats each Group I (control) and Group II. In Group II intraperitoneal hydatidosis was performed. Then DMBA was applied to mammary tissues of all rats. Immunohistochemistry studies for Ki-67 and S-100 in the tumoral tissue sections of DMBA induced mammary tumor in rats were performed. TUNEL Assay was used to detect apoptotic cells of tumoral tissue. In vivo anticancer activity testing was carried out by preventing the tumorigenesis by DMBA in mammary tissue of rats. The expressions of the Ki-67 and S-100 protein decreased in rats who had Hydatid Disease (HD) (Group II), compared with the control rats (Group I). TUNEL positive cells were higher in rats with HD (Group II), compared with the control rats (Group I). In vivo studies showed that HD prevented the tumorigenesis by DMBA in mammary tissue of rats with 50 percent.In the light of the evidence the present study showed that HD may have chemopreventive effects on DMBA induced breast cancer.

Identification and characterization of lactic acid bacteria isolated from traditional cone yoghurt

Kamil Bostan,Ayla Unver Alcay,Semiha Yalçin,Ufuk Eren Vapur,Mustafa Nizamlioglu 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.6

Cone yoghurt is a yoghurt variety produced by adding only pine cones to milk without culture in a limited area of Turkey. The present study was conducted to identify and characterize lactic flora in traditional cone yoghurt. Morphological, cultural, physiological, biochemical, and genotypic characteristics were employed to identify lactic acid bacteria isolates from cones and cone yoghurts. Streptococcus salivarius subsp. thermophilus (S. thermophilus) and Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) were obtained from both cones and yoghurts. Among the isolates, L. plantarum was frequently isolated except for these two bacteria (S. thermophilus and L. bulgaricus). The results indicate that the cone yoghurt has a mixed microflora contrary to the yoghurt produced by the addition of a starter culture and S. thermophilus, and L. bulgaricus in cone yoghurt originates from the pine cones.

Validity and reliability of performance tests as balance measures in patients with total knee arthroplasty

( Devrim Can Sarac ),( Bayram Unver ),( Vasfi Karatosun ) 대한슬관절학회 2022 대한슬관절학회지 Vol.34 No.-

Purpose: This study aimed to investigate validity and reliability of the Timed Up and Go Test (TUG), 10 Meter Walk Test (10MWT), Single Leg Stance Test (SLST), 2 Minute Walk Test (2MWT), and Five Times Sit-to-Stand Test (5xSST) for evaluating balance in patients with total knee arthroplasty (TKA). Materials and Methods: This cross-sectional study included 41 participants who had undergone TKA 6 months before the study due to osteoarthritis. Participants performed the TUG, 10MWT, SLST, 5xSST, and 2MWT. Each of the tests was performed twice, with a 1-day interval between tests. Intraclass correlation coefficient (ICC) models were used to determine the test-retest reliability. The level of correlations between performance tests and Berg Balance Scale and Fall Efficacy Scale-International were used to establish concurrent and convergent validity of the performance tests, respectively. Results: The mean age of the subjects was 64.07 ± 10.57 years. All tests showed excellent reliability (ICC > 0.94), excluding SLST that demonstrated good test-retest reliability (ICC = 0.72). All of the tests (SLST, 10MWT, 5xSST, 2MWT, TUG) were found to have good validity (rho > 0.704). Conclusions: According to these results, TUG, 10MWT, SLST, 5xSST, and 2MWT are reliable and valid outcome measures in patients with TKA, and could be used to assess balance after TKA surgery.

Comparison of transverse dental changes induced by the palatally applied Frog appliance and buccally applied Karad’s integrated distalizing system

Fatma Deniz Uzuner,Emine Kaygisiz,Fatih Unver,Tuba Tortop 대한치과교정학회 2016 대한치과교정학회지 Vol.46 No.2

Objective: To compare the transverse dental changes induced by the palatally applied Frog appliance and buccally applied Karad’s integrated distalizing system(KIDS). Methods: We evaluated the pre- and post distalization orthodontic models of 39 patients, including 19 treated using the Frog appliance, which is palatally positioned (Frog group), and 20 treated using KIDS, which is buccally positioned (KIDS group). Changes in intermolar and interpremolar distances and the amount of maxillary premolar and molar rotation were evaluated on model photocopies. Wilcoxon and Mann-Whitney U tests were used for statistical evaluations. A p-value of < 0.05 was considered statistically significant. Results: Significant distopalatal rotation of premolars and distobuccal rotation of molars were observed in Frog group (p < 0.05), while significant distopalatal rotation of molars (p < 0.05), with no significant changes in premolars, was observed in KIDS group. The amount of second premolar and first molar rotation was significantly different between the two groups (p < 0.05 and p < 0.001, respectively). Furthermore, expansion in the region of the first molars and second premolars was significantly greater in KIDS group than in Frog group (p < 0.001 for both). Conclusions: Our results suggest that the type and amount of first molar rotation and expansion vary with the design of the distalization appliance used.

Health Beliefs Concerning Breast Self-examination of Nurses in Turkey

Sevinc Tastan,Emine Iyigün,Ayse Kılıc,Vesile Unver 한국간호과학회 2011 Asian Nursing Research Vol.5 No.3

Purpose: The purpose of the study was to evaluate the health beliefs regarding breast self-examination (BSE) and their relationship with age, educational status and history of breast cancer in the family among nurses working in a university hospital. Methods: A cross-sectional design was used, with a convenience sample of 381 nurses at a military university hospital in Ankara in Turkey. Data were collected by using a personal data form and the Champion’s Health Belief Model Scale. Descriptive statistics, logistic regression, Mann-Whitney U test and Kruskal Wallis Test were conducted. Results: The proportion of nurses reported doing BSE regularly is 47.2%. Controlling variables such as age,body mass index, the age at first birth, breast cancer in the family history and educational background,we found that the subscales of the health belief model, BSE benefit (OR ¼ 0.782), self-efficacy (OR ¼ 0.919), and risk perception (OR ¼ 0.114) have statistically significant effects on the risk of not making BSE. Conclusion: It is important to be aware of the health beliefs of nurses regarding BSE so that their own health can be protected and improved. Beneficial attitudes and behaviors of nurses regarding BSE will enable them to provide more effective services to women regarding breast cancer. Understanding the nurses’ health beliefs, attitude and behavior that are influential to make BSE will guide nursing practices towards early diagnosis of breast cancer at the societal level.

Effect of surface treatments on shear bond strength of resin composite bonded to CAD/CAM resin-ceramic hybrid materials

Gungor, Merve Bankoglu,Nemli, Secil Karakoca,Bal, Bilge Turhan,Unver, Senem,Dogan, Aylin The Korean Academy of Prosthodonitics 2016 The Journal of Advanced Prosthodontics Vol.8 No.4

PURPOSE. The purpose of this study was to assess the effect of surface treatments on shear bond strength of resin composite bonded to thermocycled and non-thermocycled CAD/CAM resin-ceramic hybrid materials. MATERIALS AND METHODS. 120 specimens ($10{\times}10{\times}2mm$) from each material were divided into 12 groups according to different surface treatments in combination with thermal aging procedures. Surface treatment methods were airborne-particle abrasion (abraded with 50 micron alumina particles), dry grinding (grinded with $125{\mu}m$ grain size bur), and hydrofluoric acid (9%) and silane application. According to the thermocycling procedure, the groups were assigned as non-thermocycled, thermocycled after packing composites, and thermocycled before packing composites. The average surface roughness of the non-thermocycled specimens were measured after surface treatments. After packing composites and thermocycling procedures, shear bond strength (SBS) of the specimens were tested. The results of surface roughness were statistically analyzed by 2-way Analysis of Variance (ANOVA), and SBS results were statistically analyzed by 3-way ANOVA. RESULTS. Surface roughness of GC were significantly lower than that of LU and VE (P<.05). The highest surface roughness was observed for dry grinding group, followed by airborne particle abraded group (P<.05). Comparing the materials within the same surface treatment method revealed that untreated surfaces generally showed lower SBS values. The values of untreated LU specimens showed significantly different SBS values compared to those of other surface treatment groups (P<.05). CONCLUSION. SBS was affected by surface treatments. Thermocycling did not have any effect on the SBS of the materials except acid and silane applied GC specimens, which were subjected to thermocycling before packing of the composite resin.