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In recent times, the point absorber Wave Energy Converter (WEC) has gained popularity due to its practicality. Investigating the parameters of the Hydraulic Power Take-Off (HPTO) in the WEC, including hose diameter and check valve variations, is crucial. This study analyzes optimization using the Sequential Quadratic Programming (SQP) method in MATLAB/SimScape, leading to a more comprehensive understanding of the interactions among HPTO components, such as hydraulic cylinders, check valves, hoses, accumulators, motors, and generators. Key system performance indicators, including pressure drop, flow rate, and power output, were assessed in both single and two-point absorber HPTO configurations. The optimization process yielded a maximum hydraulic power output of 7.33 kW, a mechanical power output of 6.41 kW, and an electrical power output of 5.4 kW using a 2-inch hose diameter. Additionally, utilizing a two-point absorber model enhanced power generation capacity by 47.4%, reaching 9.45 kW. The findings highlight the significant pressure drop at the check valve, with the 2-inch hose model experiencing a drop of 31.874 bar. These results demonstrate that optimizing HPTO parameters can significantly improve the efficiency of converting wave energy into electricity, providing valuable design recommendations for WEC technology.

Dewi Ikawati,1 Amelia Ganefianty,2 Nursiswati Nursiswati,3 Urip Rahayu,3 Titis Kurniawan,3 Tuti Pahria3 1Master Program of Nursing Universitas Padjadjaran, Bandung, Indonesia; 2Hasan Sadikin Hospital, Guest Lecturer Faculty of Nursing, Universitas Padjadjaran, Bandung, Indonesia; 3Faculty of Nursing, Universitas Padjadjaran, Bandung, IndonesiaCorrespondence: Nursiswati Nursiswati; Dewi Ikawati, Department Medical-Surgical Nursing, Faculty of Nursing, Universitas Padjadjaran, Citra Graha Handayani, Citra Utama street No. 22, Sumedang, Bandung, 45362, Indonesia, Tel +6281294885959, Email nursiswati@unpad.ac.id; dewi22013@mail.unpad.ac.idIntroduction: Incessant Ventricular Tachycardia is a condition characterized by multiple episodes of Ventricular Tachycardia (VT) in 24 hours, persisting despite efforts to stop the arrhythmia. In this condition, sympathectomy as the surgical procedure is considered a permanent intervention and the last resort when medications prove ineffective. This procedure comprises the cutting or clamping of sympathetic nerves to prevent the transmission of nerve signals. Therefore, this study aims to present a case report of post-sympathectomy nursing management in a patient with Incessant Ventricular Tachycardia.Case Presentation: A 59-year-old female patient was admitted to the high-care unit with a diagnosis of post-sympathectomy, Incessant Ventricular Tachycardia due to Arrhythmogenic Cardiomyopathy. Nursing problems based on NANDA included decreased cardiac output, gas exchange impairment, and activity intolerance. Furthermore, the nursing interventions for the condition included self-care management and collaboration with an anesthesiologist and cardiologist. The interventions encompassed cardiac care, airway management, and activity therapy. Tele-nursing was also conducted through video calls to monitor the patient after hospital care.Results: The planned nursing care was effective in preventing common complications that often occur after the surgical procedure. The most important key aspect is regular maintenance and monitoring. The patient was discharged on the third day after the surgery with no complaints of shortness of breath, palpitations, and gradual resumption of activities.Conclusion: Sympathectomy procedures could successfully be used to treat patients through multidisciplinary collaboration. Furthermore, nurses could emphasize post-operative care management to expedite recovery and improve patient quality of life.Keywords: sympathectomy, role of nurses, post-operative care

Ocean waves represent a substantial renewable energy source, prompting this study's exploration of harnessing this potential via multi-point floating absorbers equipped with hydraulic Power Take-Off (PTO) systems. The study's primary motivation is to comprehensively model a Wave Energy Converter (WEC), including the hydraulic PTO system's control mechanism and protection system. To optimize the WEC design, we first investigate the hydrodynamic parameters of the floating absorber, employing potential flow theories and assessing the effects of varying the diameter-to-draft ratio. Our research involves analyzing Response Amplitude Operators (RAOs) and hydrodynamic forces for different ratios to identify the most effective design, followed by using computed wave forces as inputs for PTO simulations in MATLAB/SimScape to determine the unit parameters. The analysis of RAOs and wave-exciting forces reveals that diameter-to-draft ratios between 0.67 and 1.0 yield the best WEC performance, offering promising recommendations. In the final step, we compare the performance of single and multi-point absorber system simulations, assessing factors such as pressure drop, flow rate, and power output at the hydraulic motor. This comparison concludes that multi-point absorbers generate a more stable power output than their single-absorber counterparts.

In recent times, the point absorber Wave Energy Converter (WEC) has gained popularity due to its practicality. Investigating the parameters of the Hydraulic Power Take-Off (HPTO) in the WEC, including hose diameter and check valve variations, is crucial. This study analyzes optimization using the Sequential Quadratic Programming (SQP) method in MATLAB/SimScape, leading to a more comprehensive understanding of the interactions among HPTO components, such as hydraulic cylinders, check valves, hoses, accumulators, motors, and generators. Key system performance indicators, including pressure drop, flow rate, and power output, were assessed in both single and two-point absorber HPTO configurations. The optimization process yielded a maximum hydraulic power output of 7.33 kW, a mechanical power output of 6.41 kW, and an electrical power output of 5.4 kW using a 2-inch hose diameter. Additionally, utilizing a two-point absorber model enhanced power generation capacity by 47.4%, reaching 9.45 kW. The findings highlight the significant pressure drop at the check valve, with the 2-inch hose model experiencing a drop of 31.874 bar. These results demonstrate that optimizing HPTO parameters can significantly improve the efficiency of converting wave energy into electricity, providing valuable design recommendations for WEC technology. [ABSTRACT FROM AUTHOR]

The present work evaluated the characteristics of ciplukan (Physalis angulata L.) microcapsule extracts prepared by spray drying method. Different water ratios namely X1 (1:2), X2 (1:5), and X3 (1:10), and maltodextrin concentrations namely Y1 (5%) and Y2 (10%) were applied in a spray drying system to produce microcapsule extracts. Investigations of physical properties (pH, moisture, water activity, total solid, solubility, and colour), as well as morphological characteristics by scanning electron microscopy (SEM) and functional properties (antioxidant, total phenolic, total flavonoid, and quercetin content) were carried out. Results showed that water ratio and maltodextrin gave a significant effect on the physical properties of microcapsule extract with X1 (1:2) and Y1 (5 %) having significant effect on total phenolic, flavonoid, and quercetin contents, and antioxidant properties of ciplukan extract microcapsule. Furthermore, the scanning electron microscopy (SEM) illustrated the morphological structure of microcapsule extract, which showed a spherical structure. All combinations of water ratios and maltodextrin concentrations showed agglomeration, except for X1Y2. In correlation analysis using partial least square, the antioxidant activity of microcapsule extract was proportional to physicochemical properties, total phenolic, total flavonoid, and quercetin contents of microcapsule extract. The present work revealed that water extraction ratios and maltodextrin concentrations affected microcapsule extract of ciplukan. The combination of X1 (1:2) and Y1 (5%) retained the functional properties of ciplukan microcapsule extract. [ABSTRACT FROM AUTHOR]

The future thermal power plant is expected to operate at higher temperature to improve its efficiency and to reduce greenhouse gas emission. This target requires better corrosion properties of ferritic steels, which commonly used as materials for superheater and reheater of boiler tubes. In this work, chromium enrichment on the surface of ferritic steel is studied. The deposited chromium is expected to become a reservoir for the formation of chromia protective layer. Chromium was deposited on the substrate of steel by pack cementation process for two hours at the temperature of 850ºC, 950ºC and 1050ºC, respectively. XRD analysis indicated that chromium was successfully deposited at all temperatures. Somehow, SEM cross sectional image showed that continuous layer of chromium was not continuously formed at 850oC. Therefore, this research clarify that chromium enrichment by pack cementation may be conducted at the temperature above 950°C.