• 제목/요약/키워드: Challenge procedure

Search Result 118, Processing Time 0.025 seconds

Encryption-based Image Steganography Technique for Secure Medical Image Transmission During the COVID-19 Pandemic

  • Alkhliwi, Sultan
    • International Journal of Computer Science & Network Security
    • /
    • v.21 no.3
    • /
    • pp.83-93
    • /
    • 2021
  • COVID-19 poses a major risk to global health, highlighting the importance of faster and proper diagnosis. To handle the rise in the number of patients and eliminate redundant tests, healthcare information exchange and medical data are transmitted between healthcare centres. Medical data sharing helps speed up patient treatment; consequently, exchanging healthcare data is the requirement of the present era. Since healthcare professionals share data through the internet, security remains a critical challenge, which needs to be addressed. During the COVID-19 pandemic, computed tomography (CT) and X-ray images play a vital part in the diagnosis process, constituting information that needs to be shared among hospitals. Encryption and image steganography techniques can be employed to achieve secure data transmission of COVID-19 images. This study presents a new encryption with the image steganography model for secure data transmission (EIS-SDT) for COVID-19 diagnosis. The EIS-SDT model uses a multilevel discrete wavelet transform for image decomposition and Manta Ray Foraging Optimization algorithm for optimal pixel selection. The EIS-SDT method uses a double logistic chaotic map (DLCM) is employed for secret image encryption. The application of the DLCM-based encryption procedure provides an additional level of security to the image steganography technique. An extensive simulation results analysis ensures the effective performance of the EIS-SDT model and the results are investigated under several evaluation parameters. The outcome indicates that the EIS-SDT model has outperformed the existing methods considerably.

Outcome analysis of biplanar mandibular distraction in adults

  • Chattopadhyay, Debarati;Vathulya, Madhubari;Jayaprakash, Praveen Ambadivalappil;Kapoor, Akshay
    • Archives of Craniofacial Surgery
    • /
    • v.22 no.1
    • /
    • pp.45-51
    • /
    • 2021
  • Background: Mandibular deficiency leading to facial asymmetry causes cosmetic deformity as well as psychological stigma for the patient. Correction of these mandibular asymmetries is a major challenge. The study investigates the efficacy of bidirectional mandible distraction for the treatment of mandibular deficiency. Methods: This prospective study included six individuals aged between 17 and 24.4 years. Five patients had hemifacial microsomia and one had unilateral temporomandibular joint ankyloses. All patients underwent mandibular distraction osteogenesis. Postoperative skeletal changes in affected mandible, and changes in occlusal plane and oral commissure cant were evaluated using three-dimensional reconstruction. Patient satisfaction and understanding of the procedure were assessed through three questionnaires administered during pre-distraction, distraction and post-distraction phases. Results: In pre-distraction phase, aesthetic appearance seemed to be the primary indication for surgery. In distraction phase, pain while chewing was the primary handicap. In post-distraction phase all patients were satisfied with the aesthetic outcome. The facial deformity was improved through mandibular distraction osteogenesis. On the affected side in all the patients, height and length of the mandible increased. Canting of the occlusal plane and oral commissure was corrected. Conclusion: Bidirectional mandible distraction is an effective treatment for correction of mandible deformities in adult patients.

On the validation of ATHLET 3-D features for the simulation of multidimensional flows in horizontal geometries under single-phase subcooled conditions

  • Diaz-Pescador, E.;Schafer, F.;Kliem, S.
    • Nuclear Engineering and Technology
    • /
    • v.54 no.9
    • /
    • pp.3567-3579
    • /
    • 2022
  • This paper provides an assessment of fluid transport and mixing processes inside the primary circuit of the test facility ROCOM through the numerical simulation of Test 2.1 with the system code ATHLET. The experiment represents an asymmetric injection of cold and non-borated water into the reactor coolant system (RCS) of a pressurized water reactor (PWR) to restore core cooling, an emergency procedure which may subsequently trigger a core re-criticality. The injection takes place at low velocity under single-phase subcooled conditions and presents a major challenge for the simulation in lumped parameter codes, due to multidimensional effects in horizontal piping and vessel arising from density gradients and gravity forces. Aiming at further validating ATHLET 3-D capabilities against horizontal geometries, the experiment conditions are applied to a ROCOM model, which includes a newly developed horizontal pipe object to enhance code prediction inside coolant loops. The obtained results show code strong simulation capabilities to represent multidimensional flows. Enhanced prediction is observed at the vessel inlet compared to traditional 1-D approach, whereas mixing overprediction from the descending denser plume is observed at the upper-half downcomer region, which leads to eventual deviations at the core inlet.

Removal of a Bronchial Foreign Body by Bronchoscopic Cryotherapy: A Case Study

  • Kim, Hyoyeon;Byun, Gwanghyun;Lee, Sang Joon;Woo, Seung Hoon
    • Medical Lasers
    • /
    • v.10 no.1
    • /
    • pp.55-59
    • /
    • 2021
  • A foreign body in the airway can be a potentially life-threatening event. The diagnosis and treatment of foreign bodies in the airway are a challenge for otolaryngologists. Despite the improvements in medical care and public awareness, approximately 3,000 deaths occur each year from foreign body aspiration. A high degree of vigilance is required to ensure prompt treatment and avoid the complications of foreign body aspiration. The author encountered a case of a 77-year-old female patient who had aspirated an unknown foreign body that was fixed in her main bronchus. An initial attempt was made to remove it with a flexible bronchoscope but failed due to the patient's hypoxemic state during the procedure. Under general anesthesia, a rigid bronchoscopic examination was performed, but it was difficult to approach the object due to the bronchus curvature. Instead, a cryotherapy instrument of bronchoscopy was applied. The foreign body was frozen and removed to the carina, where a laryngoscope and laryngeal forceps were used to remove it.

Lymphovenous anastomoses with three-dimensional digital hybrid visualization: improving ergonomics for supermicrosurgery in lymphedema

  • Will, Patrick A.;Hirche, Christoph;Berner, Juan Enrique;Kneser, Ulrich;Gazyakan, Emre
    • Archives of Plastic Surgery
    • /
    • v.48 no.4
    • /
    • pp.427-432
    • /
    • 2021
  • The conventional approach of looking down a microscope to perform microsurgical procedures is associated with occupational injuries, anti-ergonomic postures, and increased tremor and fatigue, all of which predispose microsurgeons to early retirement. Recently, three-dimensional (3D) visualization of real-time microscope magnification has been developed as an alternative. Despite its commercial availability, no supermicrosurgical procedures have been reported using this technology to date. Lymphovenous anastomoses (LVAs) often require suturing vessels with diameters of 0.2-0.8 mm, thus representing the ultimate microsurgical challenge. After performing the first documented LVA procedure using 3D-augmented visualization in our unit and gaining experience with this technique, we conducted an anonymized in-house survey among microsurgeons who had used this approach. The participants considered that 3D visualization for supermicrosurgery was equivalent in terms of handling, optical detail, depth resolution, and safety to conventional binocular magnification. This survey revealed that team communication, resident education, and ergonomics were superior using 3D digital hybrid visualization. Postoperative muscle fatigue, tremor, and pain were also reduced. The major drawbacks of the 3D visualization microscopic systems are the associated costs, required space, and difficulty of visualizing the lymphatic contrast used.

Concealed Policy and Ciphertext Cryptography of Attributes with Keyword Searching for Searching and Filtering Encrypted Cloud Email

  • Alhumaidi, Hind;Alsuwat, Hatim
    • International Journal of Computer Science & Network Security
    • /
    • v.22 no.6
    • /
    • pp.212-222
    • /
    • 2022
  • There has been a rapid increase in the use of cloud email services. As a result, email encryption has become more commonplace as concerns about cloud privacy and security grow. Nevertheless, this increase in usage is creating the challenge of how to effectively be searching and filtering the encrypted emails. They are popular technologies of solving the issue of the encrypted emails searching through searchable public key encryption. However, the problem of encrypted email filtering remains to be solved. As a new approach to finding and filtering encrypted emails in the cloud, we propose a ciphertext-based encrypted policy attribute-based encryption scheme and keyword search procedure based on hidden policy ciphertext. This feature allows the user of searching using some encrypted emails keywords in the cloud as well as allowing the emails filter-based server toward filter the content of the encrypted emails, similar to the traditional email keyword filtering service. By utilizing composite order bilinear groups, a hidden policy system has been successfully demonstrated to be secure by our dual system encryption process. Proposed system can be used with other scenarios such as searching and filtering files as an applicable method.

Forming Simulation of EV Motor Hairpin by Implementing Mechanical Properties of Polymer Coated Copper Wire (고분자 필름 및 구리선 이종 물성을 고려한 EV모터용 헤어핀 성형 공정 해석)

  • D. C. Kim;Y. J. Lim;M. Baek;M. G. Lee;I. S. Oh
    • Transactions of Materials Processing
    • /
    • v.32 no.3
    • /
    • pp.122-128
    • /
    • 2023
  • As electric vehicles (EV) have increasingly replaced the conventional vehicles with internal combustion engines (ICE), most of automotive makers are actively devoting to the technology development of EV parts. Accordingly, the manufacturing process for power source has been also shifting from engine/transmission to EV motor/reducer system. However, lack of experience in developing the EV motor still remains as a technical challenge. In this paper, we employed the forming simulation based on finite element modeling to solve this problem. In particular, in order to increase the accuracy of the forming simulation, we introduced the elastic-plastic constitutive model parameters for polymer-copper hybrid wire by investigating the individual strain-stress curves, and elastic modulus of polymer and copper. Then, the reliability of modeling procedure was confirmed by comparing the simulated results with experiments. Finally, the identified mechanical properties and finite element modeling were applied to a hairpin forming process, which involves multiple deformation paths such as bending, pressing, widening, and twisting. The proposed numerical approach can replace common experience or experiment based trials by reducing production time and cost in the future.

Cross-Leg Free Flap: Crossing the Border Zone of Ischemic Limb-A Case Report of Limb Salvage Procedure following a Delayed Diagnosis of Popliteal Artery Injury

  • Hui Yuan Lam;Wan Azman Wan Sulaiman;Wan Faisham Wan Ismail;Ahmad Sukari Halim
    • Archives of Plastic Surgery
    • /
    • v.50 no.2
    • /
    • pp.188-193
    • /
    • 2023
  • Vascular injury following traumatic knee injury quoted in the literature ranges from 3.3 to 65%, depending on the magnitude and pattern of the injury. Timely recognition is crucial to ensure the revascularization is done within 6 to 8 hours from the time of injury to avoid significant morbidity, amputation, and medicolegal ramifications. We present a case of an ischemic limb following delayed diagnosis of popliteal artery injury after knee dislocation. Even though we have successfully repaired the popliteal artery, the evolving ischemia over the distal limb poses a reconstruction challenge. Multiple surgical debridement procedures were performed to control the local tissue infection. Free tissue transfer with chimeric latissimus dorsi flap was done to resurface the defect. However, the forefoot became gangrenous despite a free muscle flap transfer. His limb appeared destined for amputation in the vicinity of tissue and recipient vessels, but we chose to use a cross-leg free flap as an option for limb salvage.

Experimental analysis of blast loading effects on security check-post

  • Muhammed Rizvan Akram;Ali Yesilyurt
    • Structural Engineering and Mechanics
    • /
    • v.87 no.3
    • /
    • pp.273-282
    • /
    • 2023
  • Concrete construction, one of the oldest building practices, is commonly used in all parts of the world. Concrete is the primary building material for both residential and commercial constructions. The challenge of protecting the buildings, hence nation, against the attack of terrorism has raised the importance to explore the understanding of building materials against the explosion. In this research, a security check-post (reinforced concrete frame filled with plain cement concrete) has been chosen to study the behavior of structural elements under blast loading. Eight nitroglycerines-based dynamite blasts with varying amounts of explosive charge, up to 17 kg weight has been carried out at various scale distances. Pressure and acceleration time history records are measured using blast measuring instruments. Security check post after being exposed by explosive loading are photographed to view cracking/failure patterns on the structural elements. It is noted that with the increase of quantity of explosive, the dimensions of spalling and crack patterns increase on the front panels. Simple empirical analyses are conducted using ConWep and other design manuals such as UFC 3-340-02 (2008) and AASTP-1 (2010) for the purpose of comparison of blast parameters with the experimental records. The results of experimental workings are also compared with earlier researchers to check the compatibility of developed equations. It is believed that the current study presents the simple and preliminary procedure for calculating the air blast and ground shock parameters on the structures exposed to blast explosion.

Blunt abdominal trauma resulting in pancreatic injury in a pediatric patient in Australia: a case report

  • Harmanjit Dev;Colin Kikiros
    • Journal of Trauma and Injury
    • /
    • v.36 no.3
    • /
    • pp.310-314
    • /
    • 2023
  • Pancreatic trauma from a blunt injury is fairly uncommon in the pediatric population. Furthermore, such trauma with associated disruption of the pancreatic duct (PD) is even less prevalent and is associated with high morbidity and mortality. Pancreatic injuries in the pediatric population are often missed and hence require a thorough workup in children presenting with any form of abdominal injury. This case report describes a young boy who presented with abdominal pain and did not initially inform medical staff about any injury. For this reason, his initial provisional diagnosis was appendicitis, but he was later found to have transection of the pancreas with injury to the PD on imaging. The management of such injuries in pediatric patients often poses a challenge due to a lack of pediatric physicians trained to perform interventions such as endoscopic retrograde cholangiopancreatography. Furthermore, such interventions carry a higher risk when performed on children due to the smaller size of their pancreatic ducts. As a result, our patient had to be transferred to an adult center to undergo this procedure. Thus, maintaining a high degree of suspicion, along with a detailed history and examination, is crucial for the early diagnosis and management of pancreatic injuries.