Cristian DOICIN

Prof. Dr. Cristian DOICIN


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 November 2020 in Materials
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Journal Article
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SIMONA CAVALUSIMONA CAVALU
SIMONA CAVALU
Antoniac IulianAntoniac Iulian
Antoniac Iulian
AMAurel Mohan
Aurel Mohan
FBFlorian Bodog
Florian Bodog
CDCristian DOICIN
Cristian DOICIN
ASAugustin Semenescu
Augustin Semenescu
A novel strategy to improve the success of soft and hard tissue integration of titanium implants is the use of nanoparticles coatings made from basically any type of biocompatible substance, which can advantageously enhance the properties of the material, as compared to its similar bulk material. So, most of the physical methods approaches involve the compaction of nanoparticles versus micron-level particles to yield surfaces with nanoscale grain boundaries, simultaneously preserving the chemistry of the surface among different topographies. At the same time, nanoparticles have been known as one of the most effective antibacterial agents and can be used as effective growth inhibitors of various microorganisms as an alternative to antibiotics. In this paper, based on literature research, we present a comprehensive review of the mechanical, physical, and chemical methods for creating nano-structured titanium surfaces along with the main nanoparticles used for the surface modification of titanium implants, the fabrication methods, their main features, and the purpose of use. We also present two patented solutions which involve nanoparticles to be used in cranioplasty, i.e., a cranial endoprosthesis with a sliding system to repair the traumatic defects of the skull, and a cranial implant based on titanium mesh with osteointegrating structures and functional nanoparticles. The main outcomes of the patented solutions are: (a) a novel geometry of the implant that allow both flexible adaptation of the implant to the specific anatomy of the patient and the promotion of regeneration of the bone tissue; (b) porous structure and favorable geometry for the absorption of impregnated active substances and cells proliferation; (c) the new implant model fit 100% on the structure of the cranial defect without inducing mechanical stress; (d) allows all kinds of radiological examinations and rapid osteointegration, along with the patient recover in a shorter time.

30 January 2024 in Education Sciences
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PSPaulina Spanu
Paulina Spanu
MUMihaela-Elena ULMEANU
Mihaela-Elena ULMEANU
CDCristian DOICIN
Cristian DOICIN
Community engagement is fundamental for tertiary education, as it allows universities to connect with external stakeholders, create social impact, and improve the development of strategies for public engagement. The current study aims to evaluate the level of community engagement in tertiary education, assess the level of sustainable practices, and identify areas for improvement. The research employed a survey method, using a standardized questionnaire to gather data from 44 respondents, representing 35 European universities from nine countries. The survey covered various aspects of community engagement, such as university commitment, documentation, public awareness, investments, incentives, training, and stakeholder engagement. Quantitative analysis was employed using ANOVA and AHP to analyze the data collected from 20 questions. The results revealed that universities have a clear commitment to public engagement and have well-documented policies in place. However, there were areas identified for improvement, such as increasing investments to encourage public engagement and offering more training activities to support it. Additionally, the universities were found to have a limited target group for their community engagement activities and insufficient communication of the results of impact assessments. The findings of this study will be used to improve the development of strategies and enhance public engagement in tertiary education through the Academic Third Mission.

29 April 2023 in Bioengineering
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MUMihaela-Elena ULMEANU
Mihaela-Elena ULMEANU
IMIleana Mariana Mateș
Ileana Mariana Mateș
CDCristian DOICIN
Cristian DOICIN
MMMarian Mitrica
Marian Mitrica
VCVasile Alin Chirteș
Vasile Alin Chirteș
ASAugustin Semenescu
Augustin Semenescu
Traumatic brain injury is a leading cause of death and disability worldwide, with nearly 90% of the deaths coming from low- and middle-income countries. Severe cases of brain injury often require a craniectomy, succeeded by cranioplasty surgery to restore the integrity of the skull for both cerebral protection and cosmetic purposes. The current paper proposes a study on developing and implementing an integrative surgery management system for cranial reconstructions using bespoke implants as an accessible and cost-effective solution. Bespoke cranial implants were designed for three patients and subsequent cranioplasties were performed. Overall dimensional accuracy was evaluated on all three axes and surface roughness was measured with a minimum value of 2.209 μm for Ra on the convex and concave surfaces of the 3D-printed prototype implants. Improvements in patient compliance and quality of life were reported in postoperative evaluations of all patients involved in the study. No complications were registered from both short-term and long-term monitoring. Material and processing costs were lower compared to a metal 3D-printed implants through the usage of readily available tools and materials, such as standardized and regulated bone cement materials, for the manufacturing of the final bespoke cranial implants. Intraoperative times were reduced through the pre-planning management stages, leading to a better implant fit and overall patient satisfaction.

19 January 2021 in Sustainability
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MUMihaela-Elena ULMEANU
Mihaela-Elena ULMEANU
CDCristian DOICIN
Cristian DOICIN
PSPaulina Spanu
Paulina Spanu
Sustainability of learning environments is a key pillar of all societal development frameworks. A variety of research address the development of education as a fine balanced relation between flexibility, adaptability, innovation, and efficient resource allocation. The main limitation of current approaches is the lack of correlation between various efficiency analyses and budget expenditure of learning environments. The current research aims at undertaking a comparative evaluation of a sustainable framework in STEM intensive programs for secondary and tertiary education. This was done using several established methods like the Plan, Do, Check, Act cycle for the development main framework, the Analytic Hierarchy Process for efficiency evaluation and Value Analysis for budget expenditure allocations and improvement identification. The main framework is based on learning objectives defined in accordance with Blooms’ revised taxonomy and student feedback was collected through surveys and group feedback. The main results of the study show that the framework had overall efficiencies over the 80% threshold in both secondary and tertiary education, whilst some of the components scored under 65%, identifying immediate improvement features. Further research involves the transition to an online and mixed teaching environment, by adapting the content and framework structure with the aid of smart learning environments.

1 July 2023 in Proceedings of the International Conference on Business Excellence
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AUAndreea Maria Ungureanu
Andreea Maria Ungureanu
CDCristian DOICIN
Cristian DOICIN
CSCostel Stanca
Costel Stanca
Aurel Mihail TITUAurel Mihail TITU
Aurel Mihail TITU
The scientific paper aims to present the performance evaluation methods in ports and port organizations and the contributions that an integrated quality management system can bring. Water transport is the most reliable mode of transport, both in terms of transport capacity and in terms of consumption and environmental aspects, compared to other modes of transport. But it cannot function at an optimal level without complex and permanent on-shore management. The port organizations have an important contribution in the global performance of the port and thus in the economy of a country that is open to the sea. By approaching an integrated quality management system, port organizations can achieve the expected performance in a planned and systemic way in terms of quality, environment, logistics supply chain security, etc. The paper analyzes the performance assess in ports and port organizations, the most common applied regulations and management systems in port organizations and the advantages an integrated quality management system brings in increasing organizational performance by preventing losses and improving processes using known methodologies globally promoted such as Lean. It also highlights the relationship of mutual dependence that the port performance and the port organizations performance have on each other.

4 April 2026 in Sensors
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Journal Article
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BABogdan Felician Abaza
Bogdan Felician Abaza
ASAndrei Alexandru Staicu
Andrei Alexandru Staicu
CDCristian DOICIN
Cristian DOICIN
The paper introduces a computationally efficient semantic-aware route planning framework for indoor mobile robots, designed for real-time execution on resource-constrained edge hardware (Raspberry Pi 5, CPU-only). The proposed architecture fuses monocular object detection with 2D LiDAR-based range estimation and integrates the resulting semantic annotations into the Nav2 Route Server for penalty-weighted route selection. Object localization in the map frame is achieved through the Angular Sector Fusion (ASF) pipeline, a deterministic geometric method requiring no parameter tuning. The ASF projects YOLO bounding boxes onto LiDAR angular sectors and estimates the object range using a 25th-percentile distance statistic, providing robustness to sparse returns and partial occlusions. All intrinsic and extrinsic sensor parameters are resolved at runtime via ROS 2 topic introspection and the URDF transform tree, enabling platform-agnostic deployment. Detected entities are classified according to mobility semantics (dynamic, static, and minor) and persistently encoded in a GeoJSON-based semantic map, with these annotations subsequently propagated to navigation graph edges as additive penalties and velocity constraints. Route computation is performed by the Nav2 Route Server through the minimization of a composite cost functional combining geometric path length with semantic penalties. A reactive replanning module monitors semantic cost updates during execution and triggers route invalidation and re-computation when threshold violations occur. Experimental evaluation over 115 navigation segments (legs) on three heterogeneous robotic platforms (two single-board RPi5 configurations and one dual-board setup with inference offloading) yielded an overall success rate of 97% (baseline: 100%, adaptive: 94%), with 42 replanning events observed in 57% of adaptive trials. Navigation time distributions exhibited statistically significant departures from normality (Shapiro–Wilk, p < 0.005). While central tendency differences between the baseline and adaptive modes were not significant (Mann–Whitney U, p = 0.157), the adaptive planner reduced temporal variance substantially (σ = 11.0 s vs. 31.1 s; Levene’s test W = 3.14, p = 0.082), primarily by mitigating AMCL recovery-induced outliers. On-device YOLO26n inference, executed via the NCNN backend, achieved 5.5 ± 0.7 FPS (167 ± 21 ms latency), and distributed inference reduced the average system CPU load from 85% to 48%. The study further reports deployment-level observations relevant to the Nav2 ecosystem, including GeoJSON metadata persistence constraints, graph discontinuity (“path-gap”) artifacts, and practical Route Server configuration patterns for semantic cost integration.