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A terrestrial based communication system cannot guarantee line-of-sight for node mobility and dynamic terrestrial constraints. To solve problems, airborne communication relay, the use of unmanned aerial vehicle (UAV) as a relay node (RN) has been studied. The RN provides communication relay between disconnected networks. However, to the best of our knowledge, suitable MAC for airborne communication relay has not been studied. In airborne communication relay, two transmission phases are needed: 1) a transmitter node to the RN and 2) the RN to a receiver node. When adapting current 802.11 WLAN to airborne communication relay, contention based CSMA/CA MAC increases latency for two transmission phase. Because of increase of latency, the RN cannot relay the packet frame quick enough and continuous transmission failure occurs buffer overflow in the RN. In this paper, we studies problems when adapting 802.11 WLAN to airborne communication relay and proposes suitable MAC protocol for airborne communication relay, called a frame relay CSMA/CA (FR-CSMA/CA). The FR-CSMA/CA skips contention in relay phase to reduce latency and to solve buffer overflow in the RN. Moreover, the FR-CSMA/CA only changes parameters of the RN, so which improves performance of the current CSAM/CA scheme keeping compatibility with current communication system.

Permanent facial nerve damage is one of the most critical complications that can occur during otologic and neurosurgical procedures. As a result, facial nerve monitoring equipment is now used in most of otologic surgeries. The monitoring devices used for this purpose usually evaluate the activity of facial muscle in response to stimulation to the facial nerve. For these purposes, electromyography and the train-of-four (TOF) method is commonly used clinically, but these approaches have an important limitation: this qualitative method only depends on visual information of finger movement. Thus, in this study, a new factor that can be used to quantitatively the stage of muscle relaxation at the facial nerve was developed based on the degree of muscle relaxation and electro-stimulation. Ketamine intravenous anesthesia and isoflurane inhalation anesthesia was given to 13 rabbits. A 28 G unipolar needle-electrode was inserted at an exposed facial nerve, and stimulated (0.1 mA–5.0 mA) with an electrical stimulator. Also, the degree of muscle relaxation based electromyographic signal acquisition was performed while increasing the dose of neuromuscular blockades. After data noise reduction and normalization, the collected EMG signals were divided into 33 variables, and a new evaluation factor was developed using statistical methods based on multiple linear regression models and principal component analysis. A new evaluation factor was identified that can be used to quantitatively estimate each phase in muscle relation. The evaluating factors that were calculated in accordance with the electrical simulation resulted in improved results (r = 0.96) when compared to the existing assessment methods. (T1 ratio r = 0.72; T4/T1 ration r = 0.52).

Purpose: The goal of this study was to build an accurate digital factory that evaluates the performance of a factory using computer simulation. To achieve this goal, we evaluated the effect of worker-related variables on production in a simulation model using comparative analysis of two cases. Methods: The overall work process and worker-related variables were determined and used to build a simulation model. Siemens PLM Software's Plant Simulation was used to build a simulation model. Also, two simulation models were built, where the only difference was the use of the worker-related variable, and the total daily production analyzed and compared in terms of the in dividual process. Additionally, worker efficiency was evaluated based on worker analysis. Results: When the daily production of the two models were compared, a 0.16% error rate was observed for the model where the worker-related variables were applied and error rate was approximately 5.35% for the model where the worker-related variables were not applied. In addition, the production in the individual processes showed lower error rate in the model that included the worker-related variables than the model where the worker-related variables were not used. Also, among the total of 22 workers, only three workers satisfied the IFRS (International Financial Reporting Standards) suggested worker capacity rate (90%). Conclusions: In the daily total production and individual process production, the model that included the worker-related variables produced results that were closer to the real production values. This result indicates the importance of work er elements as input variables, in regards to building accurate simulation models. Also, as suggested in this study, the model that included the worker-related variables can be utilized to analyze in more detail actual production. The results from this study are expected to be utilized to improve the work process and worker efficiency.