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Evaluation of the efficacy of a simulation model used in oral and maxillofacial surgery education
No full textBackground: The traditional teaching methods of dental education are gradually being replaced with futuristic education methods based on the usage of educational tools such as mannequin-based simulation models and virtual reality. However, the effectiveness of mannequin-based simulation models as a learning method in the field of oral surgery remains unclear. This study aims to investigate the efficacy of training on a tooth extraction model (TEM) in view of undergraduate dental students' experience and perception of their education.
Methods: A quasi-experimental trial was implemented with two consecutive year classes, totaling 136 students at the Dentistry Faculty of Altinbas University, Turkiye. Two cohorts were created from dental students in the classes of 2023 and 2022 graduates. Cohort 1 (n = 71) received 14 h of theoretical education followed by 10 h of preclinical education on TEM. Cohort 2 (n = 65) received only 14 h of theoretical education. An anonymous questionnaire was prepared with four main sections including the preferences of learning style, participants' perceptions of the preclinical training methods, the students' competency and free text comments. Students' opinions were quantified with both 7-point Likert scales and thematic analysis. Anxiety levels were measured with the interval scale of anxiety response (ISAR). Descriptive statistics, inferential statistical and thematic analyses were conducted according to survey responses. Student characteristics were summarized and compared for two cohorts using a t-test. For all statistical analyses, the significance level was set atP ≤ 0.05.
Result: Cohort 1 was more comfortable with sequential motions performed with the forceps (P = 0.033) and felt more ready for their first clinical tooth extraction experience (P = 0.028). Cohort 2 showed a significantly higher preference for textbooks among supplementary materials (P = 0.04); however, they tended to exhibit lower self-confidence and higher anxiety levels, though without any statistical significance (P > 0.05).
Conclusion: It is clear that the students who have yet to start seeing patients benefit from increased practice with training models, which adequately reflect and represent real-life situations encountered in everyday practice
An empirical function to predict the liquefaction-induced uplift of circular tunnels
No full textTunnels buried in liquefiable soils are prone to liquefaction-induced uplift damage during strong earthquakes. Studying the parameters that affect the liquefaction-induced uplift of tunnels is crucial for enhancing the seismic resilience of tunnels, minimizing potential damage, and ensuring the safety of critical infrastructure during strong earthquakes. This study investigates the effects of tunnel diameter (D), burial depth (H), and amplitude of input shaking at the base of the soil layer (amax) on the liquefaction-induced uplift of circular tunnels using numerical simulation. A comprehensive parametric study was conducted to investigate the effect of the H/D ratio and the value of amax on the dynamic responses, such as uplifts and internal forces in the lining of the tunnel. Using the numerical results, an empirical function was proposed to estimate the liquefaction-induced uplift of circular tunnels buried in liquefiable, loose soils. Finally, the results predicted by the proposed function were compared with those of a shaking table test and a centrifuge experiment. It has been demonstrated that the burial depth of a tunnel has the greatest impact on its seismic performance. Under identical input motion, increasing the burial depth of a tunnel with a 5-m diameter from 5 to 10 m resulted in a 270% increase in uplift and increased the internal forces in the tunnel lining, noticeably
Direct-to-Implant Retropectoral Dual Plane Approach With Autologous Inferior-Based Dermal Flap: Does SPY-Elite Laser Angiographic System Reduce Complication Rates?
No full textPurposeThe study aims to investigate the complications and long-term outcomes associated with retropectoral DTI breast reconstruction with IDF utilizing the SPY-Elite laser angiographic system.Material and MethodThis retrospective study was conducted from June 2017 to January 2023. We examined 52 patients (85 breasts) treated with a direct-to-implant retropectoral dual plane approach with IDF implant coverage. Informed consent was duly obtained from every participant. Inclusion criteria dictated that patients should have medium to large breasts and a second or third degree of ptosis, as per the Regnault ptosis scale. During the intraoperative evaluation, the mastectomy flaps and IDF were assessed with the SPY-Elite laser angiographic system using near-infrared imaging. We recorded patient demographics, characteristic data, and complications.ResultsA total of 52 patients, aged 27 to 63, underwent 85 mastectomies using a direct-to-implant retropectoral approach with inferior dermal flap. The average age of the patients was 48, and their average body mass index was 30.8, with a range of 28 to 43. The distance from the nipple to the inframammary fold varied between 14 and 24 cm. The implants used had an average size of 275 cc, ranging from 250 to 650 cc. Textured anatomic implants with either moderate plus or high profile were used in all cases. The sternal notch to nipple distance for these patients ranged from 24 to 38 cm. During the evaluation using the SPY-Elite laser angiographic system, insufficient distal marginal perfusion was detected in five out of 85 inferior dermal flaps, measuring between 2 and 5 cm2. These areas were subsequently debrided, and the reconstructions were successfully completed, representing 5.8% of cases. No instances of necrosis related to IDF have been observed. There have been no failed assessments conducted by SPY ICG.In total, the complication rate was 15.2%, with minor complications occurring in 8.2% of the breasts (7 out of 85) and major ones in 7% (6 out of 85). The subjects were monitored for an average of 14 months, the duration ranging from 12 to 24 months.ResultsA total of 52 patients, aged 27 to 63, underwent 85 mastectomies using a direct-to-implant retropectoral approach with inferior dermal flap. The average age of the patients was 48, and their average body mass index was 30.8, with a range of 28 to 43. The distance from the nipple to the inframammary fold varied between 14 and 24 cm. The implants used had an average size of 275 cc, ranging from 250 to 650 cc. Textured anatomic implants with either moderate plus or high profile were used in all cases. The sternal notch to nipple distance for these patients ranged from 24 to 38 cm. During the evaluation using the SPY-Elite laser angiographic system, insufficient distal marginal perfusion was detected in five out of 85 inferior dermal flaps, measuring between 2 and 5 cm2. These areas were subsequently debrided, and the reconstructions were successfully completed, representing 5.8% of cases. No instances of necrosis related to IDF have been observed. There have been no failed assessments conducted by SPY ICG.In total, the complication rate was 15.2%, with minor complications occurring in 8.2% of the breasts (7 out of 85) and major ones in 7% (6 out of 85). The subjects were monitored for an average of 14 months, the duration ranging from 12 to 24 months. ConclusionInferior dermal flaps have considerable advantages, such as a natural autologous blood supply, a more realistic tissue thickness and texture, lower costs, and better tolerance to post-reconstruction radiation. Moreover, using the IDF technique and assessing the perfusion of IDF and mastectomy flaps through the SPY-Elite laser angiographic system appears to be a dependable, efficient way to achieve good cosmetic results in one operation, eliminating the need for additional surgeries.Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266
Textual Authenticity in the AI Era: Evaluating BERT and RoBERTa with Logistic Regression and Neural Networks for Text Classification
No full textContinental; et al.; Forvia; Hamilton; Magna; Schaeffler16th International Symposium on Electronics and Telecommunications, ISETC 2024 -- 7 November 2024 through 8 November 2024 -- Timisoara -- 205402AI-generated content impersonating human writing is an issue that has gained attention as AI spreads its wings. This particular study serves as a comparison between the existing Logistic Regression and Feedforward Neural Networks (FNNs) by employing sentence-BERT-appended models and RoBERTa in the determination of authenticity in a given text. A dataset that was balanced between human-written and AI-generated texts was utilized. Techniques like tokenization and normalization were first used, followed by feature extraction using transformer-based models. Cross-validation and confusion matrix analysis that used measures such as accuracy, precision, recall, F1 score, and ROC AUC were included to guarantee the models' robustness. The hybrid RoBERTa-FNN model that was deposed challengers was the most outstanding model in respect of precision and recall, and the highest accuracy (99.95%) was obtained as mentioned in the data. The improved performance serves as a proof of how effectively RoBERTa uses its embeddings to represent context on the fine-grained level required for this kind of text classification. This work is a stepping stone to the creation of strong AI text detection systems, besides our advancements to the knowledge of models and embedding performance with respect to text classification. The results lay emphasis on the selection of model configuration and the embedding technique, as they are the key factors in achieving the best results in practical applications. © 2024 IEEE
2000-2021 yılları arasında Türkiye'nin ihracat ve ithalat arasındaki ilişkisinin sanayi sektörü açısından analizi
Get PDFTürkiye Cumhuriyeti’nin kuruluş hedefi muasır medeniyetler seviyesinin üzerinde bir
gelişim gerçekleştirmektedir. Bu hedef doğrultusunda 1923 yılından beri sanayileşme devlet
planlamalarının baş rolü olmuştur. Sanayileşmeye önem verilmesinin sebebi ise dış ticaret
alanında pay sahibi olmak ve bu payı kalıcı bir ekonomik güce çevirmek arzusudur. Sürekli
gelişen ve değişen dünyada küreselleşme sürecinin başlaması ile birlikte sanayileşme ve
iktisadi büyüme ülkelerin gelişmişlik düzeyleri için en önemli kıstas haline gelmiştir. Bu
nedenle diğer ülkelerde de olduğu gibi Türkiye’de de belirli dönemlerde farklı stratejiler
uygulanarak sanayileşmenin en etkin hale getirilmesi için çaba sarf edilmiştir.
Bu çalışmada Türkiye’nin ithalat ve ihracat hamleleri tarihsel süreçlerle açıklandıktan sonra
2000 ile 2021 yılları arasındaki ihracat ve ithalat arasındaki ilişki sanayi sektörü özelinde
analize tabi tutulmuştur. Nitekim Türkiye’de 2000 yılı Ocak ayından - 2021 yılı Aralık
sonuna kadar aylık verileri kullanılarak sanayi sektörü açısından ihracat ve ithalat arasındaki
ilişkisinin nedensellik yöntemiyle incelenerek ilgili literatüre katkı sağlanması amacıyla
analizler gerçekleştirilmiştirThe founding goal of the Republic of Turkey is to achieve development above the level of
contemporary civilizations. In line with this goal, industrialization has been the leading role
in state planning since 1923. The reason why industrialization is given importance is the
desire to have a share in the field of foreign trade and to turn this share into a permanent
economic power. With the beginning of the globalization process in a constantly developing
and changing world, industrialization and economic growth have become the most important
criteria for the development levels of countries. For this reason, as in other countries, efforts
have been made to make industrialization most effective by applying different strategies in
certain periods in Turkey.
In this study, after Turkey's import and export moves were explained through historical
processes, the relationship between exports and imports between 2000 and 2021 was
analyzed specifically for the industrial sector. As a matter of fact, analyzes were carried out
in Turkey in order to contribute to the relevant literature by examining the relationship
between exports and imports in terms of the industrial sector with the causality method,
using monthly data from January 2000 to the end of December 2021
A strategic approach for livability improvement in the historical quarter of Gaziantep
Get PDFCity’s identity can be represented by architecture and historical heritage, it is where we can
recognize how the city’s founders have established and lived. Through the years and
according to the continuous development, the architectural heritage of Gaziantep historical
quarter had lost its capability to serve current modern life requirements and became
unliveable. The thesis argues that, the livability with its comprehensive meaning varies
according to cultures, living circumstances, time, economic, social life, and environment.
Many efforts were produced to conserve architectural heritage and make it as possible kept
up with modern life demands, although these efforts the historical quarters’ environment still
not enough to be lived in. In some cases, these restored parts were hiding behind them many
dilapidated and unauthorized buildings, which represented duality in value and livability.
This study aims to eliminate this duality and improve the livability by evaluating the
livability environmental criteria of the historical quarters of Gaziantep city according to
common indicators in the literature review and previous studies, by observation and
questionnaires, which aim to take in consideration people’s experiences in living within
these quarters and spot the light on the important urban indicators of livability environmental
dimension. The results of this evaluation will contribute to determine whether these quarters
require radical new urban plan or rehabilitation and restoration plans are enough to fill the
gap with present time living needs
Antimicrobial Effects of Nanocrystalline Silver-Loaded Wound Dressings in Full-Skin Thickness Rat Burn Wounds
No full textIntroduction: Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care to minimize mortality and morbidity. Despite major advances in the management of burn patients, infectious complications remain a major contributor to morbidity and mortality. In this experimental study, the effect of two different nanocrystalline silver dressings on Candida albicans-contaminated full-thickness burn wounds in rats was analyzed. Methods: A full-thickness skin burn was formed in a total of 24 female 200-230 gr Sprague-Dawley rats. After the burn wound was seeded with 10 8 CFU/ml standard strain of Candida albicans ATCC90028, the animals were separated into three groups, and the antifungal activity of nanocrystalline silver-containing nanofiber dressing and Acticoat dressing was compared. All rats were sacrificed on the seventh day. Biopsies were obtained from the center of the burn eschar and the paravertebral muscles beneath the burn eschar. Blood was drawn from the left ventricle, and lung biopsies were examined by performing thoracotomies. Results: There was no significant difference in Candida and bacteria growth on the burn eschar, muscle, lung tissue, and blood cultures among the groups (p>0.5). Discussion and Conclusion: Nanocrystalline silver dressings facilitate wound healing and have wide antimicrobial effects. Although these effects are well known, the antifungal and antibacterial activity of the nanocrystalline silver dressings used in our study could not be revealed
Restoration of voltage and frequency for AC islanded microgrids based on stochastic cooperative secondary control
Get PDFMicrogrid (MG) is considered one of the new models for electricity production and
distribution that relies on renewable sources of energy, and it is also the basis for this modern
model. Also, the complex interaction between different types of production equipment as
well as the unique features of renewable energy sources make MG management extremely
complex and challenging. In this thesis, stochastic distributed cooperative control (SDCC)
is suggested as a very effective approach for managing MGs. This is due to its ability to
address multiple objectives at once and its capacity to accurately represent complex systems.
Historically, hierarchical structures have been developed with three levels, each operating
on distinct time scales. Maintaining system stability and operating at a rapid rate to ensure
accurate power distribution is one of the most important primary-level functions. While the
function of the secondary control level is to return the variables that were modified by the
primary control level, The tertiary level of control is concerned with achieving optimal
economic distribution in addition to reducing the monetary cost associated with energy
production. Also, proper coordination between the main grid and MG is ensured.
Nevertheless, standalone MGs are susceptible to rapid fluctuations in both power output and
demand while exhibiting a sluggish reaction time at the tertiary control level. A recent study
indicates that it is advisable to do this control within a time frame like that employed at the
SC level. Therefore, this thesis presents a new SDCC approach in the specific setting of island AC
MGs. The primary aim is to attain SC over frequency and voltage. The controllers used in
this work are based on cooperative control methods that use a virtual impedance and
stationery proportional resonant droop control integrated with the intelligent averaging
distributed SC utilized by the Dragonfly algorithm (DA). The potential for achieving meansquare synchronization in the domain of voltage and frequency restoration for DGs is
demonstrated by the proposed methodology. In addition to attaining optimal economic
performance, it is imperative to guarantee an effective allocation of active power. This is
achieved by employing a sparse communication network, which efficiently mitigates data
congestion and minimizes the requirement for substantial information sharing in
communication. The distributed architecture under consideration offers a logical and
cohesive resolution that harmonizes the divergent objectives of reactive power sharing and
voltage management.
Comprehensive experimental and modelling investigations have supported the efficacy of
the suggested SDCC systems in MGs. These studies have focused on the operational
situations in MGs, such as load changes, the ability to adapt to changes in MG configuration
(like disconnecting and reconnecting DGs), and communication link failures. Further
experiments have been undertaken to underscore the advantages of the methodologies that
have been proposed.Mikro şebeke (MG), yenilenebilir enerji kaynaklarına dayanan elektrik üretim ve
dağıtımının yeni modellerinden biri olarak kabul edilmektedir ve aynı zamanda bu modern
modelin temelidir. Ayrıca, farklı türde üretim ekipmanlarının karmaşık etkileşimi ve
yenilenebilir enerji kaynaklarının benzersiz özellikleri, MG yönetimini son derece karmaşık
ve zorlu hale getirmektedir. Bu tezde, MG'lerin yönetimi için çok etkili bir yaklaşım olarak
stokastik dağıtılmış kooperatif kontrol (SDCC) önerilmektedir. Bu, birden fazla amacı aynı
anda ele alabilme ve karmaşık sistemleri doğru bir şekilde temsil etme kapasitesi nedeniyle
tercih edilmektedir.
Tarihsel olarak, her biri farklı zaman ölçeklerinde çalışan üç seviyeli hiyerarşik yapılar
geliştirilmiştir. Sistem kararlılığını korumak ve doğru güç dağıtımını sağlamak için hızlı bir
şekilde çalışmak, birincil seviye işlevlerinin en önemlilerinden biridir. İkincil kontrol
seviyesinin işlevi ise, birincil kontrol seviyesi tarafından değiştirilen değişkenleri geri
döndürmektir. Üçüncül kontrol seviyesi ise enerji üretimi ile ilgili parasal maliyeti
azaltmanın yanı sıra, optimal ekonomik dağılımın sağlanması ile ilgilidir. Ayrıca, ana şebeke
ile MG arasında uygun koordinasyon sağlanır. Ancak, bağımsız MG'ler hem güç çıktısında
hem de taleplerinde hızlı dalgalanmalara maruz kalırken, üçüncül kontrol seviyesinde yavaş
tepki süresi sergilerler. Son zamanlardaki bir çalışma, bu kontrolün, SC seviyesinde
kullanılan zaman çerçevesi içinde yapılmasının tavsiye edildiğini göstermektedir. Bu nedenle, bu tez, ada AC MG'lerinin belirli ortamında yeni bir SDCC yaklaşımı
sunmaktadır. Birincil amaç, frekans ve gerilim üzerinde SC elde etmektir. Bu çalışmada
kullanılan kontrolörler, sanal empedans kullanan ve Dragonfly algoritması (DA) tarafından
kullanılan akıllı ortalama dağıtılmış SC ile entegre edilen sabit orantılı rezonanslı droop
kontrolü ile işbirlikçi kontrol yöntemlerine dayanmaktadır. Önerilen metodoloji ile DG'ler
için gerilim ve frekans restorasyonu alanında ortalama kare senkronizasyonunun sağlanma
potansiyeli gösterilmiştir. Optimal ekonomik performansa ulaşmanın yanı sıra, aktif gücün
etkili bir şekilde tahsis edilmesini sağlamak çok önemlidir. Bu, veri tıkanıklığını etkili bir
şekilde azaltan ve iletişimde önemli bilgi paylaşımı gereksinimini en aza indiren seyrek bir
iletişim ağı kullanılarak gerçekleştirilir. Ele alınan dağıtılmış mimari, reaktif güç paylaşımı
ve gerilim yönetiminin farklı amaçlarını uyumlu hale getiren mantıklı ve bütüncül bir çözüm
sunmaktadır.
Önerilen SDCC sistemlerinin MG'lerdeki etkinliği, kapsamlı deneysel ve modelleme
araştırmaları ile desteklenmiştir. Bu çalışmalar, MG'lerdeki yük değişiklikleri, MG
yapılandırmasındaki değişikliklere uyum sağlama yeteneği (DG'lerin bağlantısının kesilmesi
ve yeniden bağlanması gibi) ve iletişim bağlantısı arızaları gibi operasyonel durumlara
odaklanmıştır. Ayrıca, önerilen metodolojilerin avantajlarını vurgulamak için ek deneyler
yapılmıştır
Control of a quadruple tank system using two PID controllers
No full textThis work details the mathematical modeling of a nonlinear multi-input multiple-output (MIMO) quadruple tank system (QTS) using the linearization principle and forming a Jacobean matrix to represent the system in a state space model. Using simulation tools in MATLAB software (Matlab /Simulink), a quadruple tank system is designed as well as a proportional-integral-derivative (PID) controller design to control the required liquid (water) level in the quadruple tank system (QTS).Initially, the parameters of the two PID controllers were tuned using a trial and error method, which involved setting the controller parameters manually, and the Automatically Tune the two PID controller method was then employed to tune the gain parameters of each PID controller. Finally, the genetic algorithm was used, which is a research and improvement method used to obtain the optimal values for the PID parameters. In addition, the effect of PID controllers on the steady-state response and transient response of a quadruple tank system was analysed. The results showed that using genetic algorithm-based optimization (GA) is easy to implement for both linear and nonlinear systems and that a response of a system with the presence of the PID controller, which was adjusted using a genetic algorithm (GA) with the size of population 50 and the ISE fitness function, shows the best response compared to other the classical PID controllers’ responses
The effect of supply chain transparency and agility on intention to adopt blockchain among SMEs
Get PDFThe main objective of this study was to examine how supply chain agility and transparency
impact the adoption of blockchain technology by small and medium-sized enterprises in Iraq.
Data were collected using a questionnaire distributed to 24 small and medium-sized
enterprises in the food service sector in Baghdad, Iraq. Random sampling techniques were
used to collect data. Correlation and regression analysis were used to examine the
relationship between the variables. The results showed a significant positive relationship
between supply chain agility and transparency and the adoption of blockchain technology.
In addition, a regression analysis was conducted to evaluate the impact of supply chain
transparency and agility on the adoption of the blockchain system. The results showed a
strong positive effect of supply chain agility and transparency on the adoption of the
blockchain system.Bu çalışmanın temel amacı, tedarik zinciri çevikliği ve şeffaflığının Irak'taki küçük ve orta
ölçekli işletmeler tarafından blockchain teknolojisinin benimsenmesini nasıl etkilediğini
incelemekti. Veriler, Irak'ın Bağdat kentinde yemek hizmeti sektöründe faaliyet gösteren 24
küçük ve orta ölçekli işletmeye dağıtılan bir anket kullanılarak toplanmıştır. Veri toplamak
için tesadüfi örnekleme teknikleri kullanıldı. Değişkenler arasındaki ilişkiyi incelemek için
korelasyon ve regresyon analizi kullanıldı. Sonuçlar, tedarik zinciri çevikliği ve şeffaflığı ile
blockchain teknolojisinin benimsenmesi arasında önemli bir pozitif ilişki olduğunu gösterdi.
Ayrıca tedarik zinciri şeffaflığının ve çevikliğinin blockchain sisteminin benimsenmesine
etkisini değerlendirmek için bir regresyon analizi yapıldı. Sonuçlar, tedarik zinciri çevikliği
ve şeffaflığının blockchain sisteminin benimsenmesinde güçlü ve olumlu bir etkisi olduğunu
gösterdi