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Captain or deckhand? The impact of self-leadership on employees’ work role performance under remote work
Get PDFRelying on self-determination theory, this study investigates the mediating role of psychological empowerment in the relationship between self-leadership and work role performance (task proficiency, task adaptivity, and task proactivity) in remote work settings. It also explores whether and how supervisor close monitoring moderates the indirect impact of self-leadership on work role performance. Hypotheses were tested using a two-study design including white-collar employees from a broad range of jobs and companies (Study 1) and employee-supervisor dyads working in small and medium-sized firms (Study 2) in Turkey. In Study 1, results showed that self-leadership had a positive indirect effect on employees’ work role performance through psychological empowerment. In Study 2, the cross-lagged two-wave design provided support for this indirect effect while demonstrating partial support for the moderating role of supervisor close monitoring. The current study contributes to research on self-leadership and work role performance by providing a detailed understanding of the motivational process through which self-leadership leads to increased work role performance. It also offers practical insights for enhancing self-leaders’ work role performance, particularly within the remote work context.Publisher versio
Deepsym: Deep symbol generation and rule learning for planning from unsupervised robot interaction
No full textSymbolic planning and reasoning are powerful tools for robots tackling complex tasks. However, the need to manually design the symbols restrict their applicability, especially for robots that are expected to act in open-ended environments. Therefore symbol formation and rule extraction should be considered part of robot learning, which, when done properly, will offer scalability, flexibility, and robustness. Towards this goal, we propose a novel general method that finds action-grounded, discrete object and effect categories and builds probabilistic rules over them for non-trivial action planning. Our robot interacts with objects using an initial action repertoire that is assumed to be acquired earlier and observes the effects it can create in the environment. To form action-grounded object, effect, and relational categories, we employ a binary bottleneck layer in a predictive, deep encoder-decoder network that takes the image of the scene and the action applied as input, and generates the resulting effects in the scene in pixel coordinates. After learning, the binary latent vector represents action-driven object categories based on the interaction experience of the robot. To distill the knowledge represented by the neural network into rules useful for symbolic reasoning, a decision tree is trained to reproduce its decoder function. Probabilistic rules are extracted from the decision paths of the tree and are represented in the Probabilistic Planning Domain Definition Language (PPDDL), allowing off-the-shelf planners to operate on the knowledge extracted from the sensorimotor experience of the robot. The deployment of the proposed approach for a simulated robotic manipulator enabled the discovery of discrete representations of object properties such as 'rollable' and 'insertable'. In turn, the use of these representations as symbols allowed the generation of effective plans for achieving goals, such as building towers of the desired height, demonstrating the effectiveness of the approach for multi-step object manipulation. Finally, we demonstrate that the system is not only restricted to the robotics domain by assessing its applicability to the MNIST 8-puzzle domain in which learned symbols allow for the generation of plans that move the empty tile into any given position.Japan Society for the Promotion of Science ; Osaka University ; TÜBİTAK ; Bilim AkademisiPublisher versio
Yarı iletken malzemelerin kimyasal mekanik parlatma sürecinin modellenmesi ve optimizasyonu
No full textChemical mechanical polishing (CMP) is a process of planarization of metal and dielectric surfaces typically in microelectronic devices manufacturing. Planarization is achieved by removing material from the wafer surface due to the synergistic effect of chemical and mechanical actions. In a typical CMP machine the upper part is referred to as the head. It holds the wafer, rotates and applies a force on the wafer against the lower part. The lower part is a rotating platen with an attached relatively softer pad. During CMP slurry is externally provided at a desired flow rate. The slurry is composed of chemicals (oxidizer, chelating agents, corrosion inhibitor and surfactants etc.) and nanometer-sized hard abrasive particles. The chemicals react with surface and modify the surface properties while the abrasive particles indent into the wafer surface and remove material from the wafer surface due to relative motion between the wafer and pad. The combination of chemical and mechanical effects limits our ability to understand the complex material removal mechanism in CMP. Intensive efforts have gone into developing models to explain the complex mechanism of material removal in CMP processes. The material removal rate in chemical mechanical processes have a linear dependency on applied down pressure. However, some experimental studies have reported nonlinear relationship between MRR and applied pressure. The nonlinearity can be attributed to complex interactions among the wafer, pad, abrasive particles, and chemical agents in the slurry. Therefore, in modelling CMP process coupling of both the chemical and mechanical actions is imperative to provide insight into the nonlinear behavior of MRR. Since, treating the chemical effects only as a mere means of softening the wafer surface fails to explain the nonlinear behavior of MRR in silicon dioxide CMP. Here, we present a model that couples micro-contact mechanics with diffusion of slurry into the wafer and predict MRR in CMP of silicon dioxide. The model is validated with experimental results available in the literature. In case of barrier CMP, different materials are simultaneously polished and CMP is expected to achieve a planar surface. The developed model can be utilized to optimize CMP input conditions to achieve similar material removal during barrier CMP. The material removal depends on material properties and the process input parameters. Several studies have investigated the role of slurry chemistry to achieve a certain material removal selectivity of different materials on a patterned wafer. Here we propose a methodology of achieving planar patterned surface of Cu/Mn/MnN system using a model-based optimization for mechanical process parameters. The parameters include applied force, slurry solid concentration, and abrasive particle size. The methodology has been developed via optimization using a genetic algorithm. The proposed methodology suggests that a lower downforce is the key parameter to achieve the desired material removal selectivity and planarity. The first part of the study suggests a low material removal rate (MRR) to achieve a lower standard deviation in MRR. The second part investigates the standard deviation in the thickness removed in the average time needed to remove a known thickness of the materials under consideration. It has been found that the application of lower downforce can also minimize the standard deviation in the thickness removed and a planar patterned surface can be achieved. Another way to achieve uniform material removal of different materials is the formulating of slurry chemistry. During chemical mechanical planarization process for nodes of 10nm and beyond, galvanic corrosion, material removal rate selectivity and defectivity issues need to be addressed. Better understanding of atomic scale chemical and mechanical interactions at the wafer surface to can provide useful insight and guidelines. This study also experimentally investigates the CMP Cu/Mn/MnN system with different slurry formulating. Ex-situ electrochemical analyses of Cu/Mn/MnN system were conducted to evaluate the passivation in different slurry formulations. The slurry formulations used were 0.1 M, 0.2 M, 0.3 M and 0.5 M oxidizer (H2O2) with abrasive solid loading of 2.5 %wt. The results of electrochemical analyses are compared with post CMP surface topography and material removal rate selectivity. It has been found that material removal selectivity of 1:0.8:0.88 can be achieved for Cu/Mn/MnN system, for a slurry composition of 0.3 M H2O2, under 30 N down force and 2.5 %wt. solid concentration of the slurry. The effect of mechanical components such as slurry solid concentration and applied force was also investigated. It was found that for an optimized concentration of oxidizer, more control over material removal selectivity can be achieved by optimizing the mechanical input parameters. The application of lower applied force and lower slurry solid concentration are needed to achieved the objective. This finding is in agreement with the material removal selectivity predicted with model based optimization. The model developed in this work can be used to predict MRR in a typical CMP. Also, the model can be used to optimize the CMP input conditions to achieved a desired MRR. The experimental approach proposed in this work can be beneficial to the barrier layer CMP for advanced interconnect integration schemes for sub-10 nm.Genel olarak mikroelektronik cihazların imalatında kullanılan Chemical-Mechanical Polishing (CMP), veya Türkçe tabirle kimyasal-mekanik parlatma olarak bilinen işlem metal ve dielektrik yüzeylerin düzlemselleştirmelerinde kullanılır. Kimyasal-Mekanik Parlatma (düzlemselleştirme) işleminden geçen bir malzeme aynı anda hem kimyasal hem de mekanik olarak işlemlere maruz bırakılarak yüzeyinden mikroskobik olarak parçalar çıkartılır. Tipik bir CMP makinesindeki üst kısma "baş" olarak tabir edilir ve tabakayı yerinde tutup belirlenen bir hızda döndürerek altta bulunan bir parçanın üstüne güç uygular. Altta bulunan tablanın üzerine işlemden geçecek malzemeye nispeten yumuşak bir malzemeden yapılan bir levha bağlanır. CMP işleminde içi nanometre-boyutlu parçacıklarla dolu kimyasalı (oksitleyici, şelatlayıcı, korozyon önleyici ve yüzey aktif maddelerden oluşan bir solüsyon), aynı zamanda bulamaç (slurry) olarak adlandırılır, istenilen debide malzemenin yüzeyine pompalanır. CMP süresince kimyasal yüzeyle reaksiyona girip özelliklerini değiştirirken, içinde bulunan nano-parçacıklar dönme hareketi nedeniyle yüzeyi fiziksel olarak değiştirir. CMP'deki kimyasal ve mekanik etkiler nedeniyle ortaya çıkan kompleks malzeme kaldırma mekanizmasını anlama kabiliyetimizi sınırlamaktadır. Bu mekanizmayı açıklamak ve çeşitli modeller geliştirmek için yoğun çabalar harcanarak malzeme kaldırma hızının levhanın üzerine uygulanan basınçla lineer bir ilişki içinde olduğu ortaya çıkmıştır; fakat yakın zamanlarda yapılan deneylerde bu ilişkinin lineer olmadığını ispatlayan veri ortaya çıkmıştır. Malzeme yüzeyinin altta bulunan yumuşak levha ile teması, nano-parçacıklarla ve kimyasal solüsyonla olan etkileşimi lineer olamayan ilişkiye neden olabilir. Bu nedenle, CMP işlemini modellerken her iki etkileşimin (kimyasal ve mekanik) birbirine olan bağımlılıkları malzeme kaldırma hızının lineer olmayan davranışını açıklığa kavuşturmak için önemlidir. Kimyasal etkilerin yalnızca silikon devre levhası (wafer) yüzeylerini yumuşatmanın bir yolu olarak ele alınması, silikon dioksitin CMP'deki MRR'sinin doğrusal olmayan davranışını açıklayamamasına neden olabilir. Bu çalışmada, nano-parçacıkların yüzey ile teması ve kimyasalın yüzeye olan difüzyonu arasındaki ilişkiyi göz önünde bulundurarak, silikon dioksitin CMP'deki malzeme kaldırma hızını tahmin edebilen bir model sunuyoruz. Geliştirdiğimiz model, literatürde mevcut olan deneysel sonuçlar ile doğrulanmıştır. Buna ek olarak model artan basınçla silikon dioksitin malzeme kaldırma hızındaki (MRR) doğrusal olmayan artışı açıklamak için kullanılabilir. Bariyer malzemelari için yapılan CMP'de, farklı malzemeler aynı anda parlatılır ve CMP'nin düzlemsel bir yüzey elde etmesi beklenir. Ayrıca, geliştirilen model bariyer CMP işlemi sırasında homojen malzeme kaldırma elde etmek için CMP koşullarını optimize etmek için kullanılabilir. Malzemenin özelliklerine ve CMP'ye parametrelerine göre malzeme kaldırma işlemi farklılık gösterir. Yapılan çeşitli araştırmalarda, istenilen miktarda malzeme kaldırımını gerçekleştirebilmek için bulamaç (slurry) kimyasının farklı malzemelerle yapılan desenli levhaların üzerindeki etkisi gözlemlenmiştir. Burada, mekanik işlem parametrelerini optimize edebilmek için bahsedilen modeli kullanarak Cu/Mn/MnN sistemlerinin düzlemsel desenli yüzeyini elde etmek için bir metodoloji öneriyoruz. Uygulanan kuvvet, bulamaç katı konsantrasyonu ve aşındırıcı parçacık boyutları istenilen yüzey karakteristiklerini yakalamamızı sağlayacak parametrelerdır. Bu parametreleri kullanarak genetik algoritma yardımı ile model tabablı optimizasyon yapılmıştır. Ortaya çıkan metodoloji, istenilen malzeme kaldırma oranı ve düzlemselliğini elde edebilmek için düşük düzeyde uygulanan kuvvetin önemli bir parametre olduğunu öne sürüyor. Araştırmanın ilk kısmı, malzeme kaldırma oranında (MRR) daha düşük bir standart sapma elde etmek için düşük bir MRR öneriyor. Araştırmanın ikinci kısmı ise, gereken ortalama süre içinde kaldırılan malzeme kalınlığındaki standart sapmayı incelemektedir. Uygulanan kuvveti azaltmak, çıkartılan malzeme kalınlığındaki standart sapmayı en aza indirebileceği ve düzlemsel desenli yüzey elde edilebileceği bulunmuştur. Farklı malzemelerin homojen bir şekilde kaldırmasını sağlamanın bir başka yolu, bulamaç kimyasının formüle edilmesidir. 10nm ve daha küçük düğümler (nodes) için kimyasal ve mekanik düzlemselleştirme işlemi sırasında galvanik korozyon, istenilen malzeme kaldırma oranı ve kusurluluk sorunlarının göz önünde bulundurulması gereklidir. Levha üzerindeki atomik boyutlarda olan kimyasal ve mekanik etkileşimlerin daha iyi bir şekilde anlaşılması faydalı bilgiler ve öneriler sağlayabilir. Bu çalışma aynı zamanda Cu/Mn/MnN sistemlerinin CMP'de çeşitli bulamaç (slurry) formülasyonları deneysel olarak araştırmaktadır. Farklı bulamaç formülasyonlarında pasivasyonu değerlendirmek için Cu/Mn/MnN sistemlerinin ex-situ elektrokimyasal analizleri yapılmıştır. Kullanılan bulamaç formülasyonları sırasıyla 0.1 M, 0.2 M, 0.3 M, 0.4 M, 0.5 M oksitleyici (H2O2) ve %2.5 bulamaç katı konsantrasyonu içermektedir. Elektrokimyasal analizlerden gelen veriler, CMP işlemi sonrası yüzey topografisi ve malzeme kaldırma oranı seçiciliği ile karşılaştırılmıştır. Cu/Mn/MnN sistemleri için 1:0.8:0.88'lik malzeme kaldırma seçiciliğine ulaşabilmek için, 0.3 M H2O2 bulamaç birleşimi, %2.5'luk katı konsantrasyonu ve 30 N kuvvetin gerekli olduğu bulunmuştur. Bulamaç katı konsantrasyonu ve uygulanan kuvvet gibi mekanik bileşenlerin etkisi de araştırmıştı. Amaca ulaşmak için daha düşük uygulama kuvveti ve bulamaç katı konsantrasyonu kullanılması gerekli olduğu bulunmuştur. Bu çalışmada geliştirilen model, tipik bir CMP işleminde MRR'yi tahmin etmek için kullanılabilir. Ayrıca geliştirilen model, istenilen MRR'ye ulaşmak için CMP giriş koşullarını optimize etmek için kullanılabilir. Bu çalışmada önerilen deneysel yaklaşım, 10-nm ve altı için geliştirilmiş ara bağlantı entegrasyon şemaları bariyer katmanı CMP için faydalı olabilir
Hydrogenated carbon monolayer in biphenylene network offers a potential paradigm for nanoelectronic devices
No full textA metallic carbon monolayer in the biphenylene network (specified as C ohs) becomes an insulator upon hydrogenation (specified as CH ohs). Patterned dehydrogenation of this CH ohs can offer a variety of intriguing functionalities. Composite structures constituted by alternating stripes of C and CH ohs with different repeat periodicity and chirality display topological properties and can form heterostructures with a tunable band-lineup or Schottky barrier height. Alternating arrangements of these stripes of finite size enable one to also construct double barrier resonant tunneling structures and 2D, lateral nanocapacitors with high gravimetric capacitance for an efficient energy storage device. By controlled removal of H atom from a specific site or dehydrogenation of an extended zone, one can achieve antidoping or construct 0D quantum structures like antidots, antirings/loops, and supercrystals, the energy level spacing of which can be controlled with their geometry and size for optoelectronic applications. Conversely, all these device functions can be acquired also by controlled hydrogenation of a bare C ohs monolayer. Since all these processes are applied to a monolayer, the commensurability of electronically different materials is assured. These features pertain not only to CH ohs but also to fully hydrogenated Si ohs.Academy of Science of Turkey ; High Performance and Grid Computing Center ; National Center for High-Performance Computing of Turkey ; TUBITAK ULAKBIM ; Alexander von Humboldt-Stiftung , Ulusal Yüksek Başarımlı Hesaplama Merkezi, Istanbul Teknik Üniversitesi ; Kırıkkale Üniversitesi ; Bilim Akademisi ; TÜBİTAK ; Leibniz-Rechenzentru
The impact of leadership styles on performance and mediating effect of organizational culture: A study in flight schools
No full textNowadays, the aviation sector is growing rapidly and the need for human resources in the airline industry is increasing. In order to meet the increasing pilot need, the number of flight schools and universities that provide pilot training with the support of relevant authorities is also increasing. This increase in the number of student pilots is accompanied by questions about how to ensure the continuity of quality and safety in flight training. In this context, it is very important for the flight schools to evaluate the variables that may affect the student pilot performance and to take the necessary precautions. In our study teacher leadership and organizational culture are assessed as important variables and examined. In aviation literature, there is a very small number of explanatory studies on flight performance and leadership. Additionally, no study has been found on teacher leadership of student pilots. In this context, how leadership styles affect student pilots' performances positively and negatively was investigated in our research. Organizational culture is considered as an important predictor of performance in today's organizations. In this context, it has emerged that studies have been carried out that the organizational culture is an important variable in improving organizational and individual performance. Leadership styles of teacher pilots and organizational culture have been explored in the student pilots' performance process. In this context, our work has included performance, leadership styles and organizational culture. Regarding the methodology part of this study, 151 student pilots in the flight training organizations formed the universe and a survey was conducted, analysed and explained. Considering the effect of dynamic leadership, the present study analysed the impact of leadership and culture on flight performance. It is assumed that the most effective leadership styles can be found within group dynamics consisting of members who have diverse and individual cultural orientations. Individual differences that are caused by cultural norms can be considered as the outcomes of leadership behaviour. It was concluded that flight crew leadership cannot be analysed without considering the culture variable since behaviour is influenced by both individual and environmental factors. Moreover, since the performance outcomes of the crew resource management were evaluated, the cultural attitude of the crew and leader was considered.Publisher versio
A two-generation study: The transmission of attachment and young adults’ depression, anxiety, and social media addiction
No full textSocial media use is on the rise among young adults (YA) and evidence suggests a positive association between social media addiction (SMA) and the psychological symptoms of depression and anxiety globally. However, the contribution of attachment and its transgenerational influence on YAs’ SMA and psychological symptoms have not been widely explored. Thus, we examined how parental reports of attachment (anxiety and avoidance) can directly and through YAs’ attachment predict YAs’ SMA, depression and anxiety symptoms. A sample of 375 YAs (MAge = 21.22) and their parents completed the Emotions in Close Relationships-Revised Questionnaire (Fraley et al., 2000), and the Brief Symptom Inventory (Deragotis, 1992). The SMA Scale (Sahin, 2018) was responded to by only YAs. We tested the pattern of associations in a path model. Parental attachment anxiety predicted YAs’ attachment anxiety and only paternal attachment avoidance predicted YAs’ attachment avoidance. YAs’ attachment anxiety and avoidance predicted their depression and anxiety. However, YAs’ attachment anxiety uniquely predicted their SMA. Both parents’ attachment anxiety indirectly predicted the link between YAs’ attachment anxiety and depression, but only paternal attachment avoidance indirectly predicted the association between YAs’ attachment avoidance and depression. Furthermore, paternal attachment avoidance indirectly predicted the association between YAs’ attachment avoidance and anxiety symptoms. Maternal attachment anxiety indirectly predicted SMA via YAs’ attachment anxiety. While parental anxiety and paternal avoidance may impact YAs’ symptoms, YAs’ and maternal attachment anxiety can shape SMA. The findings about the differential role of attachment in YAs’ psychological symptoms and SMA can facilitate further research and interventions
Centroidal momentum observer: Towards whole-body robust control of legged robots subject to uncertainties
No full textThis paper aims to provide robust dynamic motion control and eliminate parameter uncertainty in single-legged robots with a centroidal momentum-based control algorithm. In order to ensure the continuity of the movement despite external disturbances, the disturbance observer (DOB), which is frequently used in the motion control literature, is used. A one-legged robot model was simulated using MSC ADAMS, and then a centroidal momentum-based control algorithm and Zero Moment Point (ZMP)-based control algorithm were developed. The performances of the controllers were tested in the simulation environment in line with three different scenarios, unknown load, external forces and external momentum disturbances. The controllers were evaluated by comparing the selected reference orbital positions with the center of mass (CoM) positions on the x and z axes and the ZMP positions on the x-axis. The simulation results satisfactorily validated the proposed centroidal momentum observer as it performed well in all tested conditions.TÜBİTA
Hybrid workplace: Activity-based office design in a post-pandemic era
No full textN/AAustralian University Librarians ; University of SydneyPublisher versio
Marrying WebRTC and DASH for Interactive Streaming
No full textWebRTC is a set of W3C and IETF standards that allows the delivery of real-time content to users, with an end-to-end latency of under half a second. Support for WebRTC is built into all modern browsers across desktop and mobile devices, and it allows for streaming of video, audio and data. While the original focus of WebRTC has been on videoconferencing, it is increasingly being used today for real-time streaming of premium content because its ultra-low latency features enable several new user experiences, especially those that involve user interactivity, that are not easy to deliver or even possible with the traditional broadcast or streaming delivery protocols. Because of this increasing usage for premium content, the integration of WebRTC with the de facto adaptive streaming protocols such as MPEG's Dynamic Adaptive Streaming over HTTP (DASH) is essential. This paper gives information about the DASH Industry Forum's exploration activity on this very subject
“Generation Me”: An intra-nationally bounded generational explanation for convergence and divergence in personal vs. social focus cultural value orientations
No full textResponding to calls by international business scholars to examine contextual factors driving cultural change in developing and traditionally collectivistic countries, we examine cultural values shift in one such country, Turkey, from 1998 to 2019. Confirming study hypotheses, results evidenced a trajectory toward individualism. The percentage of respondents endorsing personal focus values in 2019 was over double that in 2009. Generational differences drove this shift – Late Millennials (born 1992–2001) in 2019 were over twice as likely to endorse personal over social focus values as same-age Early Millennials (born 1982–1991) in 2009. These trends were most pronounced in the most urbanized Turkish provinces