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School readiness : a psychopedagogic study of children from a deprived communityNaidoo, Subromony Ramloo. January 1994 (has links)
Submitted in fulfillment of the requirements for the degree of Master of Education in the Department of Educational Psychology at the University of Zululand, 1994. / The aim of mis study was:
* to describe the life-world of pre-school children from a deprived community from a psychopedagogical perspective; and
* to determine in the light of findings obtained certain guidelines according to which accountable support could be instituted in order to meet the needs of pre-school children from a deprived community.
As introduction a psychopedagogical perspective on pre-school children is given. Education as a true human activity which finds its expression in the relationship between adult and child is examined more closely. From a psychopedagogical perspective the deprived child finds himself in a situation of dysfunctional education mainly because he goes through life with inadequate assistance and guidance of a responsible parent or adult. This results in the psychic life of the pre-school child being under-actualized. The lack of responsible adult intervention and accompaniment, which is based on the pedagogical principles of love, trust and authority, results in fee deprived child forming relationships within his life-world which are inadequate for his emancipation. The child from a deprived community feils to constitute a meaningful life-world.
It would appear that poverty together with environmentally disadvantaged conditions such as overcrowding, insufficient personal, financial and social resources, discrimination and deprivation, all interact with each other, resulting in under-actualization of the psychic life of the pre-school child.
Research literature has shown that parents of children from deprived communities were in no position to provide their children with any assistance, guidance or support. In most instances parents themselves have had little or no formal education. Families live in overcrowded homes with no electricity and proper sanitation. In most cases both parents work, leaving very early in the morning and returning late in the afternoon. The children are left on their own with hardly any control over mem.
In the light of the findings of this research, the following was recommended:
* That bridging module readiness classes should be established for children turning five years of age and that professionally qualified educators should be placed in charge of these children;
* that educational programmes for parents, teachers, school management staff, pupils and social workers should be organised to meet the varied needs of both parents and children especially from deprived communities; and
* that pre-schools should be established, registered, fully financed and controlled by the State with clearly formulated aims which are not only achievable, but are also in accordance with the realisation of the ultimate aim of education, namely, adulthood.
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Visual Perception in Pre-School ChildrenBardwell, Howard Mark 01 May 1972 (has links)
This study was undertaken to determine if sessions in discrimination tasks with the aid of instructional cues would influence the visual perceptual abilities of pre-school children. The research was conducted in the Child Development Laboratories at Utah State University. Twenty children were used--ten in the experimental group and ten in the control group. The ten children in the experimental group were given training in performing tasks that required ability in visual perception. The ten children in the control group received no such training.
It was found that the ten children who received the individualized instruction scored significantly higher on post-test visual discrimination tasks than did the ten children who received no training. The children who received the training made a significant increase in their perceptive ability. This was indicated by a comparison of beginning test scores with end ing test scores.>/p>
There was no significant difference in the visual perception abilities of boys and girls or older and younger children as measured in the visual discriminations tasks.
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Identifying Perceptions that Contribute to the Development of Successful Project Lead the Way Pre-engineering Programs in UtahMcMullin, Keith 01 May 2013 (has links)
Many secondary schools in Utah have adopted the Project Lead the Way (PLTW) pre-engineering program. Little research has been conducted in Utah to show how successful these programs are or what factors are perceived to contribute to that success. This research is about defining PLTW program success and identifying factors perceived to improve success. This was accomplished by interviewing career and technical education directors in Utah who have the PLTW program in their districts. Questionnaires were also developed to question PLTW teachers, school administrators, and counselors with PLTW in their schools about factors that might contribute to PLTW program success. A successful PLTW program in Utah was found to be a program that was perceived to meet the goals of implementation, had the ability to attract adequate student enrollment, and was perceived to promote scholarly student achievement. It was found that successful PLTW programs (a) utilize dynamic teachers taking advantage of teacher professional development, (b) capitalize on student interest in the subject and differentiate learning models and environments, (c) utilize a collaborative effort between schools, industry, and community, (d) advertise class offerings and program benefits so students can make wise class choices during registration, and (e) make sure resources and facilities are available for all the curriculum requirements.
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Pre-formulation of a novel nucleotide analogue / Preformulering av en nukleotid analogRabizadegan, Mariam January 2019 (has links)
Previous studies have shown that the molecule MR1, a cGMP analogue, may be a suitable drug for neurodegenerative eye diseases. These diseases cause the eyesight to greatly deteriorate which in turn can result in the patient becoming blind. In this thesis, several salt forms of MR1 were synthesized and characterized to generate the drugs physicochemical properties, such as solubility and solid-state behavior. This in order to determine the drugs pre-formulation data. Synthesis of MR1 Na+ and MR1 Free form were performed in order generate material for solubility studies and solid state characterizations. Solid-state characterization was done in terms of X-ray, Microscopy, Hot Stage Controller, DSC, TGA and DVS. All salt forms, expect for the Free form, indicated crystallinity through X-ray analyses. However, none of the salt forms showed any clear melting point after being evaluated by DSC. TGA analysis of MR1 Na+ salt form indicated a huge weight decrease. A total amount of 15 % of the sample decreased over a very short time range in just a few seconds. The result is very extraordinary and should be controlled and analyzed once again. Results regarding amorphicity of MR1 Free form did not completely comply with results from DVS and X-ray. Further analyses should therefore be performed with extra material to obtain a more consistent result. Moreover, the solubility of the salt forms was determined and it was observed that MR1 Na+ indicated to be most soluble in all the tested buffers, as compared to MR1 TEAH+ and MR1 Free form. The pre-formulation data from this thesis are of importance for the work on understanding how the drug MR1 behaves. The work carried out in this thesis will continue (beyond the scope of this bachelor thesis) and the results herein will be used for further studies of neurodegenerative eye diseases. / Studier har visat att molekylen MR1, en cGMP analog, kan vara ett lämpligt läkemedel för neurodegenerativa ögonsjukdomar. Dessa sjukdomar leder till att synen kraftigt försämras vilket kan leda till att patienten förlorar sin synförmåga. I detta examensarbete har olika saltformer av MR1 syntetiserats för att frambringa molekylens preformuleringsdata. Denna preformuleringsdata kommer sedan användas för framtida studier inom forskningsområdet. Olika saltformer av MR1 har syntetiserats och karakteriserats med avseende på molekylens fysikalkemiska egenskaper såsom löslighet och karakterisering av dess fasta tillstånd. Syntetisering av MR1 Na+ och MR1 fri form har utförts för att få fram prover till löslighetsstudier och karakterisering av dess fasta tillstånd. Karakteriseringen av saltformernas fasta tillstånd utfördes genom tillämpning av röntgenmetoder, Mikroskopi, Hot Stage Controller, DSC, TGA och DVS. Alla saltformer förutom den fria formen visade sig ha kristallina inslag. Ingen av salterna visade någon tydlig smältpunkt efter att ha analyserats i DSC instrumentet. TGA analysen visade 15 % viktminskning för MR1 Na+ saltet, vilket är ett relativt ovanligt resultat och bör kontrolleras och repeteras ännu en gång. När MR1 fri form analyserades i DVS och röntgen instrumentet för att detektera hur amorft saltet är överstämde resultaten inte med varandra. Analysen bör därmed kontrolleras och repeteras. Löslighetsstudierna visade att MR1 Na+ har högst löslighet i jämförelse med MR1 TEAH+ och MR1 fri form när salterna analyserats i olika buffertar.
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Use of Pre-Rigor Deboned Beef from Holstein Cattle for Sausage ProductionTheradiyil Sukumaran, Anuraj 10 August 2018 (has links)
The objectives of this study were to determine the effects of deboning time (pre- and post-rigor), processing steps (grinding - GB; salting - SB; batter formulation - BB), and storage time on the microbiological, technological, sensory, and willingness-to-pay attributes of beef sausage. Using the chuck primals from 5 24-month-old Holstein steers, beef was deboned within 2 h post-mortem (pre-rigor) or 72 h (post-rigor) and processed to sausages using beef bratwurst spice mix, water/ice slurry, corn syrup, erythorbate, nitrite, salt, and 0.25% w/w sodium tripolyphosphate and a typical cooking cycle ending at 74 ¡ãC. Samples were collected during grinding, salting, batter formulation, and storage of cooked sausages. Beef deboning time did not influence bacterial counts (P ¡Ý 0.138). However, salting of raw ground beef resulted in a 0.4-log reduction in both aerobic plate count and Salmonella (P ¡Ü 0.001). Lactic acid bacteria increased from 0.5 log on d 0 to 3.8 log on d 120 of vacuum storage (P ¡Ü 0.019). The pH was greater in pre-rigor GB and SB than in post-rigor GB and SB (P < 0.001). However, deboning time had no effect on metmyoglobin reducing activity, cooking loss, and color of raw beef mixtures. Protein solubility of pre-rigor SB (124.3 mg/kg) tended to be greater than that of post-rigor SB (113.9 mg/kg; P = 0.071). TBARS were greater in BB but decreased during vacuum storage of cooked sausage (P ¡Ü 0.018). With the exception of chewiness and saltiness being 52.9 N-mm and 0.3 points greater in post-rigor sausage (P = 0.040 and 0.054, respectively), instrumental texture profile analysis and descriptive sensory analysis detected no difference between pre- and post-rigor sausages (P ¡Ý 0.153). Consumers preferred the aroma, flavor, and overall acceptability of pre-rigor sausage when compared to post-rigor sausage (P = 0.008, 0.029, and 0.011, respectively). Average predicted demand was 0.7 lb greater for pre-rigor than post-rigor sausage at any price point from $1/lb to $10/lb (P ¡Ü 0.001).
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Perceptions of the members of an online support group for women with gynecologic cancers and pre-cancers regarding online support, illness, information, and awarenessParrish, Elaine 30 April 2011 (has links)
The purpose of this study was to describe the perceptions of women diagnosed with gynecologic cancers or pre-cancers regarding participation in an online support group. The study contributed to the literature regarding online support for women with gynecologic cancers and pre-cancers. The data were analyzed using the descriptive univariate analysis method of frequency distribution presented in percentages. Out of a population of 472 members of an online support group for women with gynecologic cancers and pre-cancers, 379 (80%) participated in the study. A survey instrument consisting of 6 parts was used in this study. Part I and Part IV of the instrument were designed to collect data regarding the benefits (personal enrichments) of participating in an online support group. Part II and Part III were designed to collect data regarding the advantages of a support group being online, while Part V collected data regarding online support, illness, information, awareness, and sense of self. Part VI collected demographic information and personal information. The research questions posed in the study were developed to examine benefits, advantages, and information about participating in an online support group. The results from this study indicated that there are many benefits (personal enrichments) of online support for the women with gynecologic cancers and pre-cancers who joined these groups, as well as many advantages for them of a support group being online. The results also suggested that although these members were demographically different and were experiencing a variety of gynecologic cancers and pre-cancers, they were very cohesive in their wants and needs from online support. The results indicated that the experiences, both physical and emotional, of the women in these groups were more similar than different. Conclusions and recommendations based on the findings in this study indicated that online support is a positive addition to the lives of the women dealing with cancers and pre-cancers and that more in-depth studies should be conducted and the information disseminated to cancer patients.
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Validation of Bioluminescent Escherichia Coli O157:H7 for Use as a Pre-Harvest Food Safety ModelDuoss, Heather Ann 12 May 2012 (has links)
Cattle are naturally colonized by enterohemorrhagic Escherichia coli within the gastrointestinal tract. The most notorious of the enterohemorrhagic E. coli is E. coli O157:H7, which can cause serious illness to humans if ingested. To ensure that the United States has a safe food supply, research is ongoing in pre-harvest food safety and pathogen intervention strategies. While advances in pre-harvest intervention strategies are encouraging, no method has proven to completely eliminate and/or control O157:H7. A key limitation to successful pathogen intervention strategies is the inability to track and monitor pathogens in a real-time fashion. Through the use of bioluminescent plasmids harboring the luxCDABE cassette, pathogen tracking could be a viable solution. Bioluminescent plasmids are capable of facilitating the tracking, pathogenesis and physical locations of pathogens, thus enabling researchers to have a better understanding of the pathogenic process.
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Advanced Pre-processing Techniques for cloud-based Degradation Detection using Artificial Intelligence (AI)Seddik, Essam January 2021 (has links)
Predictive maintenance is extremely important to fleet owners. On-duty automobile engine failures add cost of extra towing, gas and labor expenses which can add up to millions of dollars every year. Early knowledge of upcoming failures helps reduce these expenses. Thus, companies invest considerably in fault detection and diagnosis (FDD) systems to reduce unnecessary costs. Artificial Intelligence (AI) is getting increasingly used in the data driven signal based FDD industry because it requires less labor and equipment. It also results in higher productivity since it can operate continuously. This research offers Artificial Intelligence based solutions to detect and diagnose the degradation of three Internal Combustion Engine (ICE) parts which may cause on-duty failures: lead-acid accessory battery, spark plugs, and Exhaust Gas Recirculation (EGR) valve. Since the goal behind most FDD systems is cost
reduction, it is important to reduce the cost of the FDD test. Therefore, all the FDD solutions proposed in this research are based on three types of built-in sensors: battery voltage sensor, knock sensors and speed sensor. Furthermore, the engine database, the Machine Learning (ML) and Deep Learning (DL) models, and the virtual operating machines were all stored and operated in the cloud.
In this research, eight Machine Learning (ML) and Deep Learning (DL) models are proposed to detect degradations in three vehicle parts mentioned above. Additionally, novel advanced pre-processing approaches were designed to enhance the performance of the models. All the developed models showed excellent detection accuracies while classifying engine data obtained under artificially and physically induced fault conditions. Since some variant data samples could not be detected due to experimental flaws, defective sensors and changes in temperature and humidity, novel pre-processing methods were proposed for Long Short-Term Memory Networks (LSTM-RNN) and Convolutional Neural Networks (CNN) which solved the data variability problem and outperformed the previous ML/DL models. / Thesis / Doctor of Philosophy (PhD) / Predictive maintenance is extremely important to fleet owners. On-duty automobile engine failures add cost of extra towing, gas and labor expenses which can add up to millions of dollars every year. Early knowledge of upcoming failures helps reduce these expenses. Thus, companies invest considerably in fault detection and diagnosis (FDD) systems to reduce unnecessary costs. Artificial Intelligence (AI) is getting increasingly used in the data driven signal based FDD industry because it requires less labor and equipment. It also results in higher productivity since it can operate continuously. This research offers Artificial Intelligence based solutions to detect and diagnose the degradation of three Internal Combustion Engine (ICE) parts which may cause on-duty failures: lead-acid accessory battery, spark plugs, and Exhaust Gas Recirculation (EGR) valve. Since the goal behind most FDD systems is cost
reduction, it is important to reduce the cost of the FDD test. Therefore, all the FDD solutions proposed in this research are based on three types of built-in sensors: battery voltage sensor, knock sensors and speed sensor. Furthermore, the engine database, the Machine Learning (ML) and Deep Learning (DL) models, and the virtual operating machines were all stored and operated in the cloud.
In this research, eight Machine Learning (ML) and Deep Learning (DL) models are proposed to detect degradations in three vehicle parts mentioned above. Additionally, novel advanced pre-processing approaches were designed to enhance the performance of the models. All the developed models showed excellent detection accuracies while classifying engine data obtained under artificially and physically induced fault conditions. Since some variant data samples could not be detected due to experimental flaws, defective sensors and changes in temperature and humidity, novel pre-processing methods were proposed for Long Short-Term Memory Networks (LSTM-RNN) and Convolutional Neural Networks (CNN) which solved the data variability problem and outperformed the previous ML/DL models.
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The Relation of Some Factors to Certain Difficulties Recognized by Teachers in Their TeachingWorthington, Lawrence G. 08 1900 (has links)
This study has been made for three purposes: 1) to find out what difficulties experienced and inexperienced teachers recognize in their teaching; 2)to find out what factors have influenced these difficulties; and 3)to find out, if possible, which difficulties could be eliminated with further pre-service training.
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<strong>PRE-CHAMBER JET IGNITION IN AN OPTICALLY-ACCESSIBLE CONSTANT-VOLUME GASOLINE ENGINE</strong>Dong Eun Lee (16637403) 08 August 2023 (has links)
<p>In Chapter 2, an experiment has been developed to investigate the passive pre-chamber jet ignition process in gasoline engine configurations and low-load operating conditions. The apparatus adopted a modified 4-cylinder 2.0L gasoline engine to enable single-cylinder operation. To reduce the complexity, the piston position was fixed at a predefined position relative to the top dead center (TDC) to simulate thermodynamic conditions at ignition and injection timings. High-speed Infrared (IR) imaging was applied to visualize the jet penetration and ignition process inside the main cylinder and to investigate the cyclic spatial variability. Two passive pre-chambers with different total nozzle areas and numbers of nozzles were used. In addition, the pre-chamber volume and pressure at ignition timing were varied to examine their effect on jet ignition performance. Misfire behavior was observed in the main chamber of all test cases, and the results suggested that the main cause is a high Residual Mass Fraction (RMF) in the pre-chamber affecting the subsequent cycle. A larger total nozzle area, smaller volume, higher pressure, and fuel-lean operation tended to mitigate the misfire behavior. For a test case with a spark pressure of 6 bar, a reduced cyclic variability in terms of coefficient of variation peak cylinder pressure (COVPmax) from 10.03% to 7.38% and combustion phasing variation from 81 crank angle degree (CAD) to 12 CAD were observed with increasing pre-chamber volume-to-area (V/A) ratio from 59.37 m to 103.11 m, but slightly higher misfire frequency was observed, from 46.67% to 50.00%, suggesting an accurate combination of pre-chamber design parameters is needed to improve overall performance at low-load operation.</p>
<p>In Chapter 3, it examines the influence of passive pre-chamber nozzle diameter and dilution level on jet formation and engine performance. Utilizing a modified constant-volume gasoline direct injection engine with an optically-accessible piston, we tested three passive pre-chambers with nozzle diameters of 1.2, 1.4, and 1.6 mm, while nitrogen dilution varied from 0 to 20%. With the help of high-speed imaging, we captured pre-chamber jet formations and subsequent flame propagation within the main chamber. Our novel findings reveal that asymmetric temporal and spatial jet formation patterns arising from pre-chambers significantly impact engine performance. The larger nozzle diameter pre-chambers exhibited the least variation in jet formation due to their improved scavenging and main mixture filling processes, but had the slowest jet velocity and lowest jet penetration depth. At no dilution condition, the 1.2 mm-PC demonstrated superior performance attributed to higher pressure build-up in the pre-chamber, resulting in accelerated jet velocity and increased jet penetration depth. However, at high dilution condition, the 1.6 mm-PC performed better, highlighting the importance of scavenging and symmetry jet formation. This study emphasizes the importance of carefully selecting the pre-chamber nozzle diameter, based on the engine's operating conditions, to achieve an optimal and balanced configuration that can improve both jet formation and jet characteristics, as well as scavenging.</p>
<p>In Chapter 4, it investigates the influence of passive pre-chamber nozzle diameter on jet ignition and subsequent main chamber combustion under varying load conditions and dilution levels using a constant-volume optical gasoline direct injection engine. The results reveal that as the load decreases, both fuel availability and flow conditions deteriorate, leading to delayed and inferior jet characteristics that affect main chamber ignition and combustion processes. In high and medium load conditions without dilution, the smallest nozzle diameter pre-chamber (1.2mm-PC) shows improved jet ignition and main combustion due to earlier jet ejection, enhanced penetration, and intensified jet. This is facilitated by the smaller nozzle diameter enabling faster and higher pre-chamber pressurization. Conversely, under low load conditions, the largest nozzle diameter pre-chamber (1.6mm-PC) performs better, likely due to improved scavenging and reduced residual levels, resulting in less compromised pre-chamber combustion and subsequent jet characteristics. The nozzle diameter also has a significant impact on cycle-to-cycle variations, with smaller diameters enhancing jet ignition performance but increasing variability. The effect of external residuals (dilution) on jet ignition performance varies depending on the nozzle diameter, with the 1.6mm-PC exhibiting less degradation and demonstrating earlier jet ejection and CA50 timing compared to smaller nozzle diameter pre-chambers at higher dilution conditions. The improved scavenging and relatively lower residual levels in the larger nozzle diameter pre-chamber contribute to its increased resistance to dilution and potential extension of dilution tolerance.</p>
<p>In Chapter 5, it presents an analysis of the effects of pre-chamber nozzle orientation on dilution tolerance in a constant-volume optical engine. Using a combination of experimental and numerical methodologies, we provide novel insights into how variations in nozzle number, orientation, and size influence combustion performance under different dilution conditions. The findings reveal that an increase in the number of nozzles, for a fixed A/V ratio, tends to enhance ignition performance and stability across a range of dilution scenarios, primarily due to an increase in ignition points and a larger ignition surface area. Meanwhile, swirling pre-chambers, despite their potential to boost initial combustion performance at no dilution condition, may limit dilution tolerance due to the complexity of their internal flow dynamics and increased heat loss through nozzle surfaces. Furthermore, pre-chambers combining swirling and straight nozzle orientations fail to synergize the benefits of each type, and instead, exacerbate challenges such as heat loss, flame quenching, and unfavorable flow dynamics. These findings emphasize the complexity and nuanced trade-offs involved in optimizing pre-chamber design for improved dilution tolerance and suggest potential directions for future research in this area.</p>
<p>In Chapter 6, it investigates the behavior of pre-chamber knock in comparison to traditional spark ignition engine knock, using a modified constant-volume gasoline engine with an optically-accessible piston. The aim is to provide a deeper understanding of pre-chamber knock combustion and its potential for mitigating knock. Five passive pre-chambers with different nozzle diameters, volumes, and nozzle numbers were tested, and nitrogen dilution was varied from 0 to 10%. The stochastic nature of knock behavior necessitates the use of statistical methods, leading to the proposal of a high-frequency band-pass filter (37-43 kHz) as an alternative pre-chamber knock metric. Pre-chamber knock combustion was found to exhibit fewer strong knock cycles compared to SI engines, indicating its potential for mitigating knock intensity. High-speed images revealed pre-chamber knock primarily occurs near the liner, where end-gas knock is typically exhibited. The study identified that increasing pre-chamber nozzle diameter resulted in a larger dispersion of knock cycles and more severe knock intensity, likely due to shorter jet penetration depth requiring more time for end-gas consumption. Strategies for mitigating knock in pre-chamber combustion systems include reducing the pre-chamber volume for a fixed A/V ratio and increasing dilution level. The results of this study offer valuable insights for developing effective knock mitigation approaches in pre-chamber combustion systems, contributing to the advancement of more efficient and reliable engines.</p>
<p>In Chapter 7, a numerical investigation of different premixed gaseous injection strategies was performed to understand their impact on the scavenging and mixture formation of an air-fuel premixed pre-chamber with high exhaust gas recirculation (EGR) operations. EGR dilution is effective for reducing coolant heat loss, pumping work at throttled conditions, and mitigates knock at high-load conditions, thus increasing engine efficiency. To further extend the EGR limit of an air-fuel premixed pre-chamber engine, the effects of different injection strategies (including timing, duration, pressure, pre-chamber volume, and hardware) on the EGR level, trap efficiency, and parasitic loss were determined. Regardless of injection duration and upstream pressure, injecting too early not only increased the amount of the injected premixed gas leaking into the main chamber but also was inefficient in reducing the EGR level in the pre-chamber. To reduce the EGR level in the pre-chamber to a level where successful ignition and combustion of the pre-chamber mixture is possible, the injection timing should be delayed to be close to the ignition timing. A premixed air-fuel injection is thus proposed to reduce the time required for air-fuel mixing in the pre-chamber. With a delayed end of injection (EOI), both leakage amount and EGR level were reduced compared to the cases with earlier injection timings. The results show that an injection with 15 bar upstream pressure, 20 CA duration, EOI of −20 CAD aTDC (ignition timing), and with guided injection hardware for the base pre-chamber volume resulted in about 0.17% air compression parasitic loss, over a 94% trap efficiency, at the same time maintaining the mean EGR level in the pre-chamber below 20%, ensuring good pre-chamber combustion. With a 50% increase in pre-chamber volume from the base case, the parasitic loss increased by 65% (from 0.17% to 0.28% loss), indicating a problem with a larger pre-chamber with a separate air valve and injector.</p>
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