Auswahl der wissenschaftlichen Literatur zum Thema „Hilfsaktion Noma e.V“

Low density signature orthogonal frequency division multiplexing (LDS-OFDM), one type of non-orthogonal multiple access (NOMA), is a special case of multi-carrier code division multiple access (MC-CDMA). In LDS-OFDM, each user is allowed to spread its symbols in a small set of subcarriers, and there is only a small group of users that are permitted to share the same subcarrier. In this paper, we study the resource allocation for LDS-OFDM as the multiple access model in cognitive radio networks. In our scheme, SUs are allocated to certain d v subcarriers based on minimum interference or higher SINR in each subcarrier. To overcome the problem where SUs were allocated less than the d v subcarriers, we propose interference limit-based resource allocation with the fairness metric (ILRA-FM). Simulation results show that, compared to the ILRA algorithm, the ILRA-FM algorithm has a lower outage probability and higher fairness metric value and also a higher throughput fairness index.

Objectives To map publication trends and explore research hotspots of retinal vein occlusion (RVO) study. Methods Based on Web of Science Core Collection (WoSCC), a bibliometric analysis was carried out. The knowledge map was constructed by VOSviewer v.1.6.10 to visualize the annual publication number, the distribution of countries, international collaborations, author productivity, source journals, cited reference and keywords in this field. Results A total of 2,135 peer-reviewed papers were retrieved on RVO from 2009 to 2018. The United States ranks highest among countries with the most publications and the most active institution was Kyoto University. Noma H contributed the most publications in this field. Retina—The Journal of Retinal and Vitreous Disease was the most prolific journal in RVO research. The top cited references mainly presented anti-VEGF medications on the management of RVO. The keywords formed six clusters: (1) Risk factors and pathogenesis of RVO; (2) Metabolismof RVO; (3) Therapeutic use of corticosteroids on RVO; (4) Diagnostic methodsof RVO; (5) Management of macular edema secondary to RVO (6) Anti-VEGFtreatment of RVO. Conclusions The six major research hotspots could provide an insight into RVO research and valuable information for researchers to identify potential collaborators and partner institutions.

Temporomandibular joint (TMJ) is a unique joint in which both jaws must open synchronously for function. Any pathology in one or both joints results in functional problems with associated poor quality of life. TMJ ankylosis (TMJA) is a joint pathology as a result of bony and/or fibrous adhesion of the joint apparatus, resulting in partial or total loss of function. This is a retrospective study from two tertiary referral centers in northwest region of Nigeria from 2012 to 2016. Data retrieved include gender, age, etiology of ankylosis, duration of ankylosis, laterality of ankylosis, type of imaging technique, type of airway management, types of incision, surgical procedure, interpositional materials used, and complications. Data were analyzed using SPSS for Window version 20.0 (IBM Corp.). Results were presented as simple frequencies and descriptive statistics. A total of 36 patients with TMJA were seen during the study period; out of which 7 (19.4%) patients had maxillary extension of the ankylotic mass. There was a male: female ratio of 1.3:1. Four (57.1%) patients were within the age group between 5 and 10 years, two (28.6%) within the age group between 11 and 15 years, while only one (14.3%) was within the age group between 31 and 35 years. All the cases (7 [100%]) of maxillary extension were secondary to cancrum oris (noma). Cheek scarring as a result of management of cancrum oris was observed. In addition, intraoral fibrosis eliminating the upper and lower buccal sulci extending to the molar regions was also noted. With the involvement of the maxilla in the ankylotic mass, the authors have proposed modification of Sawhney's classification by the addition of Class V. The authors have suggested a name for the new classification to be “Modified Sawhney's Classification of Temporomandibular Joint Ankylosis”. Aggressive postoperative physiotherapy for a sufficient period of time (minimum of 6 months) is paramount.

Non orthogonal multiple access (NOMA) is a novel technology for transmission of the data with similar data-rate for users both at the cell center and the at cell edge. Due to its good cell coverage and large transmission bandwidth enables reliable communication for users located at the cell edge. The signals for the users are transmitted through entire spatial bandwidth by multiplexing in the power domain. This work presents the Simulink implementation of non-orthogonal multiple access over additive white Gaussian noise channel, Rayleigh and Rician fading channel. The NOMA Transmitter and the receiver blocks with SIC are implemented for two user and three user environments. Multipath fading environment was providing using parameter settings available in theblocks. Performance of the models implemented are analyzed with respect to Bit error rate (BER) v/s Eb/Noplots comparing using various modulation schemes over various channels. The results are tabulated and analyzed.

In this paper, we analyze an underlay two-way decode-and-forward scheme in which secondary relays use successive interference cancellation (SIC) technology to decode data of two secondary sources sequentially, and then generate a coded signal by superposition coding (SC) technology, denoted as SIC-SC protocol. The SIC-SC protocol is designed to operate in two time slots under effects from an interference constraint of a primary receiver and residual interference of imperfect SIC processes. Transmit powers provided to carry the data are allocated dynamically according to channel powers of interference and transmission, and a secondary relay is selected from considering strongest channel gain subject to increase in decoding capacity of the first data and decrease in collection time of channel state information. Closed-form outage probability expressions are derived from mathematical manipulations and verified by performing Monte Carlo simulations. An identical scheme of underlay two-way decodeand-forward relaying with random relay selection and fixed power allocations is considered to compare with the proposed SIC-SC protocol, denoted as RRS protocol. Simulation and analysis results show that the non-identical outage performances of the secondary sources in the proposed SIC-SC protocol are improved by increasing the number of the secondary relays and the interference constraint as well as decreasing the residual interference powers. Secondly, the performance of the nearer secondary source is worse than that of the farther secondary source. In addition, the proposed SIC-SC protocol outperforms the RRS comparison protocol, and effect of power allocations through channel powers is discovered. Finally, derived theory values are precise to simulation results. Keywords: Successive interference cancellation, superposition coding, power allocation, underlay cognitive radio, non-orthogonal multiple access, outage probability. 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Noma is a neglected non-contagious disease of the face and mouth affecting children living in extreme poverty. Due to the quick spread of the disease, the mortality rate is estimated at 90% when treatment is not started within two weeks of onset. Even though Hilfsaktion Noma e.V. (HAN) has been actively spreading awareness about the disease and offering treatment and reconstructive surgery, the mortality rate has not decreased. Moreover, patients reaching the noma centre often present severe sequela, affecting their speech, eating and drinking ability. Therefore, this study investigates the challenges faced by noma patients to seek medical care in Niger and how to overcome them. A mixed-method approach was performed; a survey among healthcare workers of HAN was supplemented with an interview with a key informant of the organisation in order to get a wider understanding of the possible challenges noma patients encounter. Accessibility to healthcare, as well as distance to the hospital and lack of transportation means were identified as the challenges with the highest impact on the health-seeking behaviour of noma patients. The lack of knowledge about noma and treatment costs were the second main challenge. This information gap is reflected in stigmatization, inadequate health care staff and seeking aid from traditional healers, which seriously endangers the life of patients. To overcome these challenges, a community-based surveillance system in combination with a multisectoral approach was proposed. This low-cost system can not only eliminate noma by facilitating the early detection of noma patients, but it can also contribute to sustainable health in Niger and other countries in the Noma belt.

Analiza ritmi£nosti števnih podatkov je postala pomembna v mnogih vidikih znanosti, inženirstva in celo ekonomije. Obstajajo metode z namenom detekcije ritmi£nosti zveznih podatkov, ki pa ve£i-noma niso primerne za analizo števnih podatkov. V prispevku predstavimo metodologijo, ki omo-go£a analizo ritmi£nosti v števnih podatkih. Me-toda združuje metodo cosinor z uporabo razli£-nih ra£unskih regresijskih modelov, ki so primerni za analizo števnih podatkov. Omogo£a tako de-tekcijo ritma kot tudi ocenitev parametrov ritma, primerjavo zgrajenih modelov in iskanje optimal-nega števila komponent za metodo cosinor ter is-kanje najbolj ustreznega tipa števnega modela. Vzpostavljena metoda omogo£a primerjavo zazna-nega ritma v odvisnosti od razli£nih parametrov ritmi£nosti in izra£un njihovih intervalov zaupa-nja. Celotno metodologijo smo testirali na te-denski periodi£nosti realnih podatkov COVID-19 obolenj v Sloveniji.