Engineering Society Research Articles

Indoor air quality control at national-level regulations: A special case in Indonesia

Introduction: While many national-level governments have worked to tighten atmospheric air quality standard, the Authors observe, Indoor Air Quality (IAQ) control as part of building-codes have remained understudied and not yet enforced in many national-level regulations. The COVID-19 pandemic seemed to trigger an immediate response worldwide for IAQ control. Indoor air pollutants need to be tightly regulated. International agencies have produced recommendations to cope with the pandemic, however, national- level IAQ standards and building codes have been slow to adapt.
 Materials and methods: IAQ regulations from various nations worldwide were studied along with the international standards: The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), and World Health Organization (WHO). A comprehensive review was conducted comparing the national-level building codes and regulations as legal implementation instruments. Focus group discussions were also conducted to complement preliminary findings and further analysis.
 Results: Except for Indonesia, bacteria and fungi have been categorized as infectious aerosols in many national-level regulations that fare up to the international standards as indoor air pollutants with their acceptable levels. However, while they set thresholds for pollutants, their effectiveness regulating IAQ in public buildings remain unknown. It also found that there is a significant lack of national building codes in Indonesia.
 Conclusion: The COVID-19 epidemic raises awareness of IAQ. The health aspect is currently being prioritized, particularly in Indonesia, where the majority of related regulations are still fragmented and prioritize energy conservation over health. This study can inform policymakers with evidence of IAQ control and practices worldwide for applicable regulatory building and implementation, as well as for health emergency and disaster risk management.

The impact of a kinetic façade on the lighting performance and energy efficiency of a public building: the case of Dubai frame

ABSTRACT This paper proposes a novel framework for selecting a kinetic system strategy to enhance the performance of the building while preserving its architectural concepts. Dubai Frame, which is one of the most iconic buildings in Dubai, was chosen to act as a case study. A parametric model was developed for adjusting the opening ratios of the panel’s solid parts in the façade geometrics using the Grasshopper plugin in Rhino. Integrated Environmental Solutions (IES) simulation software was used and validated by calibration of the actual monthly electricity bills and real measurement of lux value against the predicted readings. The simulation assessed the total energy savings in terms of electricity and cooling loads and cost savings in terms of the KW per hour of electricity generated. In addition, it examined daylight illuminance levels for nine scenarios of the proposed kinetic system. The research has revealed several important results that include the finding that the optimal kinetic system results in 20% energy savings and 31% reduction in daylight illuminance levels while taking into account the current situation of the building and its aesthetic values. Abbreviations: UAE, United Arab Emirates; IEQ, Indoor Environmental Quality; PCM, Phase change materials; ASHRAE, The American Society of Heating, Refrigerating and Air-Conditioning Engineers; LEED, Leadership in Energy and Environmental Design system; HVAC, Heating, ventilation and air conditioning; RH, Relative Humidity; WWR, Window Wall Ratio; LR, Literature Review; RSMF, Room Surface maintenance factor; LMF, Luminaire maintenance factor; VAT, Value added tax; IHG, Internal Heat Gains

Experimental investigation of desiccant dehumidification with four different combinations of silica gel desiccant wheel on indoor air quality

Indoor air quality (IAQ) describes the air quality within buildings and other structures, particularly concerning how it affects the health and comfort of building inhabitants. Your likelihood of experiencing indoor health issues can be decreased by being aware of and controlling common indoor contaminants. In addition to maintaining indoor relative humidity at or below 65%, The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) recommends temperatures between 21 and 26 °C in the summer and 20–24 °C in the winter. The EPA advises using humidity levels between 30 and 60% to stop mold from growing. Silica gel, lithium chloride, and molecular sieves 5A are excellent for dehumidification due to their strong moisture adsorption capability and potential for regeneration. Choosing the right desiccant depends on factors like adsorption capacity, pore size, and chemical compatibility, which are crucial for dehumidification applications and environments. This study compares the performance of silica gel desiccant wheels with three additional composite materials for air dehumidification, which is unusual in this work because very few studies of these combinations have been provided. For all desiccant wheels, the various operating parameters of the needed dehumidification process have been investigated and compared. For adsorption and regeneration rate, the performance of three different composite desiccant wheels was examined and compared experimentally. This experimental evaluation reveals that the composite desiccant wheel (silica gel-lithium chloride-molecular sieve 5A) has a higher adsorption and regeneration rate than others. When a composite desiccant wheel made from silica gel-lithium chloride, silica gel-molecular sieve 5A, and silica gel-lithium chloride-molecular sieve 5A was compared to the performance of a silica gel desiccant wheel, the percentage improvements in adsorption rate were 34.99%, 43.58%, and 85.5%, and the percentage increases in regeneration rate were 5.65%, 7.08%, and 14%.

In-Situ early anomaly detection and remaining useful lifetime prediction for high-power white LEDs with distance and entropy-based long short-term memory recurrent neural networks

High-power white light-emitting diodes (LEDs) have demonstrated superior efficiency and reliability compared to traditional white light sources. However, ensuring maximum performance for a prolonged lifetime use presents a significant challenge for manufacturers and end users, especially in safety–critical applications. Thus, identifying functional anomalies and predicting the remaining useful lifetime (RUL) is of enormous importance in the operational longevity of the device. To address such challenges, this study proposes a combination of distance-based Mahalanobis distance (MD), entropy generation rate (EGR), and deep learning models for improved anomaly detection and RUL prediction accuracy. Unlike conventional health indicators based on luminous flux data that are challenging to monitor relevant optical performance, the MD and EGR methods are employed to extract in-situ monitored thermal and electrical data as new health indicators. Long short-term memory recurrent neural networks (LSTM-RNN) and convolutional neural networks (CNN) are established to detect anomalies and predict the RUL. The accelerated degradation tests of 3 W high-power white LED have been conducted, and the online and offline collected experimental data are deployed for model development and performance evaluation. The performance of the proposed methods is compared against the Illuminating Engineering Society of North America (IESNA) TM-21 method. The results indicate that LSTM-RNN, when combined with either MD or EGR, can detect anomalies with significantly fewer data (70 %) than is typically required. Furthermore, a significant improvement in prediction accuracy in RUL prediction based on MD and EGR-constructed time series health indicators and employed with the LSTM-RNN model demonstrates the effectiveness of the proposed methods.

Virus spreading in cruiser cabin

This paper concerns virus droplet simulations in a typical cruiser's cabin. Effects of ventilation rates and positions of the coughing person were investigated. The study also emphasizes the importance of including evaporation models to simulate the process accurately. A higher ventilation rate is not always the best strategy to avoid the spread of airborne diseases, as saliva droplets can spread further at high ventilation rates. Regardless of the ventilation strategy, they evaporate faster than the room's air renewal. One should aim for minimum droplet spreading inside the cabin and different ventilation strategies for occupied cabins. The authors propose using ventilation systems at medium flow rates of around 120 m3/h or three air changes per hour when a cabin is occupied. This value is also close to the recommended value of 108 m3/h from the latest standard by the American Society of Heating, Refrigerating and Air-Conditioning Engineers. The suggested value minimizes droplet spreading while maintaining good ventilation, comfort, and energy consumption.

Preface

The development of Geotechnical Engineering goes together through the Case Histories considering the geological and geotechnical condition of the site. The most primitive geotechnical case histories may be dated back to 4000 BC in Egypt and until today; Geotechnical case histories have been the backbone of the sustainable growth of the infrastructures for the city and other purposes. The conference on Case Histories in Geotechnical Engineering reflects the motivations of our engineers to exchange knowledge and ideas due to the many problems that arise in the last decade. The growth of the economy of Indonesia recently is amazing, and the same for most Asian countries. Together all these factors have caused the increasing need of geotechnical advisory. The awareness of the demand for keeping up with the geotechnical technology motivated our university with series of workshop and conference about Case histories in Geotechnical Engineering. In conjunction with this conference AsRTC6 (Asian Regional Technical Committee) of GeoUrban Engineering take part in the GEOCASE 2023 Conference to enhance the meaningful of this conference theme.Many universities, research institutions, contractors and geotechnical consultants have gained experience and knowledge which are suitable for particular site. Case histories are also of significant values for the state of the art practice. Hence the seminar is very important event for exchange of ideas and experience and for contribution all over the world..I would like to extend my appreciation to all of you who have been travelling from far distance and specially to the Keynote Speakers and authors who made their efforts to share their knowledge and experience to the audience. This conference cannot be successful without the support of Universitas Katolik Parahyangan – Indonesia, Universiti Teknologi Malaysia – Malaysia, National Taiwan University of Science and Technology – Taiwan, National Chung Hsing University (NCHU), Taiwan, and Universiti Tun Hussein Onn – Malaysia. Also Himpunan Ahli Teknik Tanah Indonesia (HATTI), Himpunan Ahli Konstruksi Indonesia (HAKI), International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE), Indonesian Ministry of Public Works and Housing (PUPR), and Institution of Civil Engineers (ICE) for the cooperation and continuous support.Last but not least, to all members of the committee for their endless hard work and dedication, I have to acknowledge that they are the people behind the scene, for without them, this event will not come to reality.Finally to all participants, I wish you find this conference useful and beneficial to you, and your institution.Thank you.Prof. Ir. Paulus P. Rahardjo, Ph.D.Chairman of GEOCASE 2023 ConferenceList of Conference Co-Chair, Advisory Committee, Organizing Committee are available in this pdf.

Effectiveness of Alternative Assessment Tools used in EiS-SULAM Projects for Sustainable Communities in Engineering Programme

Service-Learning Malaysia-University for Society (SULAM) approach integrates theory and practice to expose students to real-world community problems and develop their higher-order thinking skills (HOTs). However, there is a lack of research on alternative assessment tools used to evaluate SULAM projects in engineering programs. This study focuses on the assessment tools used for the Engineers in Society (EIS) course integrated with SULAM (EiS-SULAM) and their effectiveness. A questionnaire survey was administered to 462 civil engineering students who took the EiS-SULAM course during the October 2020, March 2021, and October 2021 semesters. Of the 462 students, 165 responded to the questionnaire, resulting in a response rate of 36%. The students' perspectives were triangulated with the direct attainment of the program outcomes for the course based on the assessments used. The results showed that all students met the 50% cut-off mark for the EiSSULAM course, satisfying the EAC Standard 2020 criterion. The study highlights that the four assessment tools used in the EIS course are effective, but there is a room for improvement. The students suggested the need for financial support from the university, improvements to the assessment tools, facilities such as internet, conducive environment to enhance their learning experience, and additional support from lecturers/advisors highlighting the importance of quality guidance and mentorship for student success. The study's findings could help improve engineering assessment instruments to enhance the students’ skill sets related to sustainable community. However, the use of purposive sampling may limit the generalizability of the results to other engineering programmes or institutions. The results suggest that the EIS-SULAM course is effective in developing students' HOTs and achieving essential skill sets for societal well-being. In conclusion, this study provides valuable insights into the effectiveness of assessment tools in SULAM projects for engineering programmes and its potential to develop the essential skill sets required for community and societal well-being. Future research could explore the effectiveness of SULAM in different engineering programmes and institutions using different sampling methods. In addition, promising avenue for future research is the integration of Artificial Intelligence (AI), such as ChatGPT, in the development of assessment prompts for engineering courses. This research could focus on creating AI-powered prompts aligned with course and program outcomes to enhance the efficiency and effectiveness of student evaluation.

Recent Research Trend Analysis for the Journal of Society of Korea Industrial and Systems Engineering Using Topic Modeling

Recent Research Trend Analysis for the Journal of Society of Korea Industrial and Systems Engineering Using Topic Modeling

A CFD-FEM analysis for Anaconda WEC with mooring lines

Anaconda wave energy converter (WEC) [1] is a typical flexible tube WEC design. In the past decade, the hydro-elastic performance of Anaconda model has been studied through experiments [2-3] and reduced-order numerical simulations [4-5]. However, to date, most of the undertaken research assumes that both ends of the tube are fixed, neglecting mooring lines that exist at designed conditions. The tube is allowed to move freely head to waves when mooring lines are considered. This is evident by an experiment conducted by Checkmate Flexible Engineering Ltd., where they observed a significant heave motion of Anaconda WEC, which may impact the dynamic response of WEC and further the energy conversion [6]. In our previous work [7], supported by the EPSRC project BASM-WEC (No. EP/V040553/1), a coupled numerical analysis tool using computational fluid dynamics (CFD) and finite element method (FEM) has been proposed to perform a numerical study for an Anaconda WEC model without considering mooring lines.In this paper, the coupled fluid-structure interaction (FSI) analysis tool [7] based on CFD-FEM method will be used to investigate Anaconda WEC with mooring lines. To account for the effects of free motion of WEC, we develop a sub-module to be embedded into the existing tool. The fluid and structure are solved by a two-phase CFD solver developed based on OpenFOAM and a three-dimensional FEM code CalculiX, respectively. The strong coupling between OpenFOAM and CalculiX is achieved by a multi-physics coupling tool preCICE.For the flexible tube, a commercial Natural Rubber material is studied. The hyper-elastic model YEOH is utilized to describe the nonlinear behaviour of material, and the model constants are calculated from the bi-axial tests. With the tool developed, numerical simulations are performed for different given regular waves. The flow details, velocity and pressure variation, structure deformation and stress distribution will be fully examined to better understand energy conversion performance of Anaconda WEC with mooring lines.
 References[1] Farley F J M D, Rainey R C T. Distensible tube wave energy converter: U.S. Patent 7,980,071[P]. 2011-7-19.[2] Chaplin J R, Heller V, Farley F J M, et al. Laboratory testing the Anaconda[J]. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2012, 370(1959): 403-424.[3] Heller V, Chaplin J R, Farley F J M, et al. Physical model tests of the anaconda wave energy converter[C]//Proc. 1st IAHR European Congress. 2000.[4] Farley F J M, Rainey R C T, Chaplin J R. Rubber tubes in the sea[J]. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2012, 370(1959): 381-402.[5] Babarit A, Singh J, Mélis C, et al. A linear numerical model for analysing the hydroelastic response of a flexible electroactive wave energy converter[J]. Journal of Fluids and Structures, 2017, 74: 356-384.[6] Checkmate Flexible Engineering, https://www.checkmateukseaenergy.com/, accessed 15th December 2022.[7] Huang Y, Xiao Q, Idarraga G, et al. Numerical analysis of flexible tube wave energy converter using CFD-FEA method[C]//International Conference on Offshore Mechanics and Arctic Engineering. American Society of Mechanical Engineers, 2023 (submitted).

Temporal and spatial heterogeneity of indoor and outdoor temperatures and their relationship with thermal sensation from a global perspective

People spend most of their time indoors. However, indoor temperature and individual thermal exposure are generally not considered in epidemiological studies of temperature and health. Based on the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) RP-884 Database, the ASHRAE Global Thermal Comfort Database II and the Chinese Thermal Comfort Database, this study first explored the relationship between outdoor temperature, indoor temperature and thermal sensation from a global perspective. Moreover, the potential influence of spatiotemporal heterogeneity on health studies was explored. A breakpoint was found at approximately 11.5 °C in the segmented regression of indoor and outdoor temperature, and the slope of the curve was greater when outdoor temperature was above the breakpoint (n = 67,896). Based on multi-group propensity score matching (PSM) and generalizedadditivemodels (GAM), spatiotemporal heterogeneity was found in the relationship between indoor and outdoor temperatures after adjusting for building type and year. Furthermore, the relationship between indoor temperature and thermal sensation was influenced by the outdoor temperature. This study highlights the importance of considering indoor temperature or individual thermal exposure in temperature-related health studies.

Experimental investigation of thermophysical properties of ethylene glycol based secondary fluids

Aqueous solutions of ethylene glycol are commonly used as secondary fluids in different indirect refrigeration systems and heat pumps as well as nanofluids. A very extensive literature review has been done, including more than 90 references published from 1905 to 2023. Despite the wide application and importance, especially in the energy sector, ethylene glycol solutions seem to be less investigated in low temperature ranges and more research is required to improve the quality and quantity of available data. The novelty of this paper is to investigate the most important thermophysical properties of ethylene glycol solutions in low temperatures. In this study a different approach was made and solutions having a specific freezing point temperature (between -5 and -50 ºC) rather than specific concentration were investigates in temperature ranges applicable for different cooling applications. The concentrations giving a certain freezing point temperature seemed to deviate in some cases with 1–2 wt-% between different sources. Nevertheless, the density results were in rather good agreement with all reference data. The viscosity results were lower by up to ±10% compared to reference values. Additionally, the obtained experimental results for thermal conductivity were higher by up to 12% compared to ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) data. The specific heat capacity results were higher by up to 14.6% and 5.4% than current reference data. There is a high probability that the current ASHRAE data for specific heat are actually indirectly calculated values from thermal conductivity data and not validated using differential scanning calorimetry techniques.

Looking back on 20 years of the International Society of Paddy and Water Environment Engineering (PAWEES), focusing on the period before and after the establishment of PAWEES

Looking back on 20 years of the International Society of Paddy and Water Environment Engineering (PAWEES), focusing on the period before and after the establishment of PAWEES

Integration of Deep Learning for Automatic Recognition of 2D Engineering Drawings

In an environment where manufacturing precision requirements are increasing, complete project plans can consist of hundreds of engineering drawings. The presentation of these drawings often varies based on personal preferences, leading to inconsistencies in format and symbols. The lack of standardization in these aspects can result in inconsistent interpretations during subsequent analysis. Therefore, proper annotation of engineering drawings is crucial as it determines product quality, subsequent inspections, and processing costs. To reduce the time and cost associated with interpreting and analyzing drawings, as well as to minimize human errors in judgment, we developed an engineering drawing recognition system. This study employs geometric dimensioning and tolerancing (GD&T) in accordance with the ASME (American Society of Mechanical Engineers) Y14.5 2018 specification to describe the language of engineering drawings. Additionally, PyTorch, OpenCV, and You Only Look Once (YOLO) are utilized for training. Existing 2D engineering drawings serve as the training data, and image segmentation is performed to identify objects such as dimensions, tolerances, functional frames, and geometric symbols in the drawings using the network model. By reading the coordinates corresponding to each object, the correct values are displayed. Real-world cases are utilized to train the model with multiple engineering drawings containing mixed features, resulting in recognition capabilities surpassing those of single-feature identification. This approach improves the recognition accuracy of deep learning models and makes engineering drawing and image recognition more practical. The recognition results are directly stored in a database, reducing product verification time and preventing errors that may occur due to manual data entry, thereby avoiding subsequent quality control issues. The accuracy rates achieved are as follows: 85% accuracy in detecting views in 2D engineering drawings, 70% accuracy in detecting annotation groups and annotations, and 80% accuracy in text and symbol recognition.

Daylighting Assessment of a Heritage Place of Instruction and Office Building in Alice, South Africa

Mitigation of post-occupancy building energy consumption has resulted in the change of building design to utilise ambient weather factors for indoor thermal conditioning and lighting. This has increased the construction of new buildings with large glazing façades and reduced adaptive use of heritage buildings as they are considered not designed to meet modern energy use requirements. This paper evaluates the daylighting performance of a heritage place of instruction and office building. A quantitative research approach based on building information simulation tools was adopted. Autodesk Revit 2021 and Integrated Environmental Solutions Virtual Environment (IESVE) 2021 were used in modelling and simulating the building daylighting performances. The building’s annual daylight performance analysed with climate-based daylight modelling shows that points in the analysed spaces were within the UDI300-2000 for more than 50% of the occupied period (07h00 to 17h00) in a year. The sDA300,50% was found to be 100% in most spaces, which is considered a favourable daylit space according to the Illuminance Engineering Society of North America (IESNA). Further, discomfort glare analysis revealed that the building daylight glare is imperceptible, with an average daylight glare probability of 21.2%. The 1:14 window–wall ratio contributes to the building daylighting relative to orientation without constituting visual discomfort. Overall, climate-based daylight modelling revealed that the building’s annual daylight level meets the IESNA requirements with an imperceptible daylight glare.

Optimalisasi Ventilasi Ruang Kelas untuk Mencegah Penularan Covid-19 dengan Setting Experiment

The spread of the SARS-CoV-2 virus has forced many schools to implement health protocols such as wearing masks, social distancing, and limiting the number of students in classrooms when face-to-face learning resumes as it did before the pandemic. This is due to the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC) stating that Covid-19 can spread through the air (airborne). In addition to implementing health protocols, another important thing is to maintain classroom ventilation. By increasing the ventilation of outside air into the classroom, the risk of virus transmission can be reduced, and the indoor air quality can be improved. Introducing as much outside air as possible into the room is one important way to prevent the spread of Covid-19 because it can reduce the concentration of the virus in the room. ASHRAE (American Society of Heating, Refrigerating, and Air Conditioning Engineers) recommends a minimum of 6 ACH (Air Change per Hour) for classrooms. Research conducted on one middle school classroom in Tangerang Selatan, equipped with 2 AC units and 1 window, showed that the ASHRAE standard can be met by opening the window at least 50% during learning activities and turning on 1 AC unit with the fan setting at full speed to achieve an ACH greater than 6. If besides wanting to prevent the transmission of Covid-19, you also want to create comfort during the learning process, you can turn on both AC units with the fan setting at low to full speed. Keywords: Airborne, ASHRAE, Social distancing, US-CDC, WHO

Impact of the interface on the fatigue life of steel-based explosively welded heterostructured plates

Melted zones, microcracks, shear bands, and elastic incompatibility of explosively welded materials are features that may initialize cracks at the interface and reduce fatigue strength. This study aims to determine the effect of interfacial defect-like structures on the fatigue strength of explosively welded corrosion-resistant plates. Cyclic axial loading was applied to seven distinct layer-by-layer compositions of Ti Gr 1, Zr 700 alloys, and carbon steels. The interfacial wave height as a metric of potential fatigue life influencing factors along with measured strain amplitude was applied as the input quantities for the Machine Learning based model, i.e. the Gaussian process for regression (GPR). This is a novel and successful application of GPR to estimate the effect of interfacial wave height on the fatigue life of explosively welded plates. For the first time, the effect of the interface feature on fatigue life was estimated quantitatively. The Digital Image Correlation technique was applied to measure the field of cyclic strain for the purpose of verifying if a single strain amplitude is representative of a heterostructured plate. It was found that interfacial wave height is an important feature and its increase by 100 µm reduces the fatigue life of analysed plates by 36%. Additionally, to validate the applicability of explosively welded plates to engineering structures under cyclic loading, the experimental fatigue lives were compared with the design curve of the American Society of Mechanical Engineers (ASME) code.

Tunnel lighting calculation model based on bidirectional reflectance distribution function: Considering the dynamic changes in light transmittance in road tunnels

The current tunnel lighting calculation method does not completely consider the dynamic change in light transmittance in a tunnel and reflection characteristics of the tunnel sidewall. Thus, the measured and calculated values of road surface illuminance present a considerable difference, which seriously affects the tunnel lighting design and quality evaluation. To overcome this limitation, in this study, in addition to theoretical analysis and measured experiments, the changing trend in light attenuation is analyzed and a light attenuation model is established. Next, a bidirectional reflectance distribution function that can accurately reflect the reflection characteristics of tunnel sidewall is combined with the light attenuation model and calculation steps based on optical theory to construct a tunnel lighting calculation model considering light transmittance (TLCM-LT). Finally, theoretical calculation and actual measurement verification are conducted via an experimental tunnel simulation, and the results obtained using TLCM-LT are compared with the values calculated based on the Commission Internationale de l'éclairage (CIE), Illuminating Engineering Society of North America (IESNA), and Industry Standards of the People’s Republic of China (JTG) specifications. The results show that the average relative error of the TLCM-LT in a smoke-free environment is 1.31 %. In the presence of smoke, the average relative error of the model fluctuates in the range of 2.19–6.8 % with the change in light transmittance in the tunnel, which is significantly lower than the errors obtained based on the CIE, IESNA, and JTG specifications. Compared with a cement sidewall, the average increase rates in road surface illuminance and illuminance uniformity of the highly diffuse reflective sidewall are 23.21 and 3.65 %, respectively.

Computational physiological models for individualised mechanical ventilation: a systematic literature review focussing on quality, availability, and clinical readiness

BackgroundIndividualised optimisation of mechanical ventilation (MV) remains cumbersome in modern intensive care medicine. Computerised, model-based support systems could help in tailoring MV settings to the complex interactions between MV and the individual patient's pathophysiology. Therefore, we critically appraised the current literature on computational physiological models (CPMs) for individualised MV in the ICU with a focus on quality, availability, and clinical readiness.MethodsA systematic literature search was conducted on 13 February 2023 in MEDLINE ALL, Embase, Scopus and Web of Science to identify original research articles describing CPMs for individualised MV in the ICU. The modelled physiological phenomena, clinical applications, and level of readiness were extracted. The quality of model design reporting and validation was assessed based on American Society of Mechanical Engineers (ASME) standards.ResultsOut of 6,333 unique publications, 149 publications were included. CPMs emerged since the 1970s with increasing levels of readiness. A total of 131 articles (88%) modelled lung mechanics, mainly for lung-protective ventilation. Gas exchange (n = 38, 26%) and gas homeostasis (n = 36, 24%) models had mainly applications in controlling oxygenation and ventilation. Respiratory muscle function models for diaphragm-protective ventilation emerged recently (n = 3, 2%). Three randomised controlled trials were initiated, applying the Beacon and CURE Soft models for gas exchange and PEEP optimisation. Overall, model design and quality were reported unsatisfactory in 93% and 21% of the articles, respectively.ConclusionCPMs are advancing towards clinical application as an explainable tool to optimise individualised MV. To promote clinical application, dedicated standards for quality assessment and model reporting are essential.Trial registration number PROSPERO—CRD42022301715. Registered 05 February, 2022.

Subjective Assessment of Light Environment Quality based on Human-centric Lighting

The light environment quality, in general, can be assessed from various metrics of that have been made by standard institutions such as the Indonesian National Standard (SNI), Illuminating Engineering Society (IES), or the International WELL Building Institute. However, the development of research in the field of lighting has shifted from focusing on visual quality and energy to Human-Centric Lighting (HCL). HCL requires an assessment metric to measure quality from the subjective point of view of occupants. There are two types of subjective judgments in light environment quality research, that are subjective judgments for post-experiment conditions and subjective judgments for pre & post-experiment conditions. Subjective assessment of the light environment quality based on Human-centric Lighting can be divided into three categories, that are visual, emotional and biological assessments. For the subjective assessment instrument of the visual category, researchers can use the glare sensation assessment standard. Meanwhile, for the assessment of the light environment quality from the emotional category, there is no specific standard. And for assessing the light environment quality from the biological category, researchers can use commonly used assessment standards, such as the Karolinska Sleepiness Scale (KSS), Pittsburgh Sleep Quality Index (PSQI), and Epworth Sleepiness Scale (ESS). For an assessment category that does not have a standard, the researcher can arrange a research instrument from the results of the literature review and adapt it to the conditions of the research study object.

ANALISIS PENGENDALIAN KUALITAS CACAT DIMENSI PADA HEADER BOILER MENGGUNAKAN METODE FMEA DAN FTA DI PT. IHI POWER SERVICE INDONESIA (IPSI)

IHI Power Service Indonesia is a company engaged in the Boiler Pressure Part Industry (Fabrication) in every production activity it always strives to produce quality products according to ASME standards (American Society of Mechanical Engineers). Production results are less than the maximum. In the 2020 period the total production was 28,527 tons and the number of defects was 364 tons, in the 2021 period the total production was 22,703 tons and the number of defects was 301 tons. The author uses the Failure Mode And Effect Analysis (FMEA) method and the Failure Tree Analysis (FTA) method. From the results of data processing using a Pareto diagram based on the RPN value obtained from the FMEA method, the dominant type of defect is obtained, namely Hole Distance with an RPN value of 364.5 and Dimension Length with a value of 351.17, then analyzed using FTA, at the proposed improvement stage it is proposed to use the 5W+1H method. Factors that cause defects include inaccurate and faded measuring instruments, rare maintenance on radial drilling machines and blades that are rarely replaced. Proposed improvements to reduce defects include requesting replacement of measuring instruments, carrying out regular maintenance of radial drilling drilling machines, holding shift schedules for operators, conducting training for operators.