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Pelaksanaan konstruksi conduit pengelak dan cofferdam merupakan pekerjaan rekayasa dengan ukuran yang cukup besar dan melibatkan banyak sumber daya dengan berbagai aktivitas kegiatan. Oleh karena itu, metode dan sistem manajemen yang efisien dan fleksibel diperlukan untuk menjamin pekerjaan dapat diselesaikan tepat waktu dan tepat biaya. Tujuan pada penelitian ini adalah melakukan penjadwalan pelaksanaan konstruksi conduit pengelak dan cofferdam yang merupakan bagian dari Bendungan Cijurey. Analisis permasalahan dilakukan dengan mengevaluasi jadwal pekerjaan, memberikan alternatif pemecahan masalah guna percepatan proyek dengan optimalisasi pekerjaan pada penambahan alat berat dan jam kerja. Dengan durasi awal pelaksanaan konstruksi selama 95 hari kerja, waktu pelaksanaan dapat dipersingkat dengan efisiensi sebesar 20% dengan penambahan jumlah alat berat dan sebesar 22.1% dengan penambahan jam kerja tambahan. Hal ini juga berdampak pada biaya pelaksanaan proyek yang terjadi efisien sebesar 2.21%Â dan 2.89% akibat penambahan jumlah alat berat dan penambahan jam kerja tambahan pada pelaksanaan konstruksi ini. Dapat disimpulkan bahwa penambahan durasi jam kerja membutuhkan anggaran yang lebih kecil dibandingkan dengan opsi penambahan alat berat, dan dipilih sebagai alternatif pilihan terbaik dalam efisiensi pekerjaan conduit pengelak dan cofferdam Bendungan Cijurey.

Applications of Enhanced Oil Recovery (EOR) are highly required and needed in Sudan to keep oil supply at stable levels. ”FUL” Oilfield in Sudan has shallow reservoir affected by big boundary and bottom water drive with high crude oil viscosity. This research, through a comprehensive analysis of the current producing wells, perforation intervals, CO2 temperature analysis, steam parameters optimization which using two approaches (deterministic and stochastic) were analyzed, using a combination of continues steam flooding, CO2 assisted steam flooding, and cyclic steam stimulation in the pilot test sector. CMG-STARS and CMOST AI simulators software was used in this study. By determining recovery factor (RF) as objective function. It could conclude that: CO2 assisted steam flooding even it could decrease the water cut, but its effect to increase the oil recovery factor is not considerable. Continuous steam flooding has the best oil recovery from these three methods.

The easiness of accessing video on various platforms can negatively impact if not done wisely, especially for children. Parental supervision is needed so that movies platforms avoid inappropriate displays such as violence. Violent scenes in movies can trigger children to commit acts of violence, which is not desired. Unfortunately, it is not easy to supervise them fully. This study proposed a method for automatic detection of violent scenes in movies. Automatic violence detection assists the parents and censorship institutions in detecting violence easily. This study uses Gated Recurrent Units (GRU) algorithm and wavelet as feature extraction to detect violent scenes. This paper shows comparative studies on the variation of the mother wavelet. The experimental results show that GRU is robust and deliver the best performance accuracy of 0.96 while combining with mother wavelet Symlet and Coiflets8. The combination of GRU with wavelet Coiflets8 shows better results than the predecessor.

This study was conducted to determine how implementation of management in the activities of the package service program. Management in question is how to implement management functions such as planning, organizing, staffing, directing, budgeting, and monitoring. This research is a descriptive research with a qualitative approach. Data collection techniques in this study were through interviews, observation, and literature review. The results or data obtained are analyzed using three stages, namely data reduction, then the data is presented in the form of narrative text and draws conclusions according to the problem formulation that has been described. The results of the study indicate that in running the program, the package service has implemented management functions. Activities related to planning are carefully arranged, the stages of activities, a series of times are aligned. Implementation in activities by grouping activities, division of labor and providing direct directions is also implemented so that it goes according to plan even though limited transportation facilities hinder the delivery of package services to the locations of the fostered libraries. Meanwhile, for coaching activities now no longer use the budget. Supervision is carried out by going directly to the target library, but the time to supervise the assisted library in the Jakarta area is still not on schedule.

Schizophrenia is a mental disorder caused by genetic factors and brain chemical factors. This disease requires early treatment. One way to detect schizophrenia is to use an electroencephalogram (EEG). An EEG is a device used to record signals generated by the brain’s electrical activity. This study was conducted on detecting Schizophrenia brain disorders based on EEG signals using the Alexnet Convolutional Neural Network (CNN) algorithm with SVM. CNN is a popular algorithm and state-of-the-art in machine learning, and SVM is still the baseline for comparing the proposed new methods. The dataset used in the study was taken from 32 normal subjects and 49 schizophrenic subjects. The data consisted of 3072 features. The test results show SVM has better performance than CNN, with a maximum accuracy of SVM 0.792 in comparison with CNN accuracy is 0.76. The fastest training time is SVM 0.5 seconds while CNN is 88 seconds, CNN training time is longer because CNN performs convolution calculations on five layers.

The purpose of this study were to determine the effect of enjoyment, flow experience, and trust toward the level of intention to play in online game playerunknown's battlegrounds (PUBG) mobile in Bengkulu. This study uses a quantitative approach using primary data obtained through online questionnaires. This study involved users of the game PUBG mobile in Bengkulu. The total sample in this study was 140 users of the game PUBG mobile in Bengkulu using the convenience sampling method. The data processing technique of this study used Statistical Package For Social Science (SPSS) software version 21.0. The analysis which is used including validity test, reliability test, and t test for hypothesis testing. The result revealed that; 1). Enjoyment has a positive and has a significant influence toward the level of intention to play; 2). Flow experience has a positive and has a significant influence toward the level of intention to play; 3). Trust has a positive and has a significant influence toward the level of intention to play felt by users of the PUBG mobile game in the Bengkulu.

A high performance surfactant formulation was developed using more universally accepted Winsor type phase behavior tests rather than relying primarily on interfacial tension (IFT) measurement for the first time for Daqing oilfield. A surfactant mixture of alkylbenzene sulfonate and fatty alcohol propoxylated ether sulfate was identified which was able to form middle-phase microemulsion with Daqing less reactive crude oil (acid number below 0.1 mg KOH/g crude), lower oil water IFT to ultralow level, and hold desired aqueous stability. Winsor type phase behavior tests at various water oil ratios (WORs) showed the optimum salinity changed slightly from 1.95% to 2% when WOR was increased from 5:5 to 9:1 due to the low reactivity of the Daqing crude oil. To investigate the significance of salinity on Daqing alkaline-surfactant-polymer (ASP) flooding, 4 salinity profiles were designed during coreflooding that corresponded to different types of microemulsions including III–III–I, I–III–I, II–III–I, and III–III–III. For each coreflooding, 0.3 pore volume (PV) of ASP slug with 0.3% total surfactant concentration and 0.2 PV polymer drive was injected. The results demonstrated when negative salinity gradient (3.0%–2.0%–0.5% Na2CO3 in waterflood, ASP, and polymer slugs) was applied, the highest incremental oil recovery of 45.9% original oil in place (OOIP) was achieved. If no Na2CO3 was added in water preflush prior to the injection of ASP slug, the lowest incremental recovery of 32.8% OOIP was observed. For a constant salinity profile at optimum salinity, an intermediate oil recovery (37.4%) was encountered. The measurement of surfactant and Na2CO3 concentrations in the effluents indicated that when negative salinity gradient (II–III–I) was applied, the surfactant loss in the porous media and the oil phase was moderate compared to the two corefloods with III–III–III (highest surfactant loss) emulsion and I–III–I emulsion (lowest surfactant loss). This implied that at optimized salinity profile, the surfactants were more close to hydrophobic-hydrophilic balance during the propagation in the reservoir, which showed the highest potential of increasing oil recovery for the Daqing Oilfield without significantly increasing chemical consumption.

In this study, we conducted an alkaline/surfactant/polymer (ASP) coreflood at real reservoir temperature and pressure using reservoir core plugs and active live oil. The live oil was prepared by dissolving gases (CH4 and CO2) into dead crude with acid number of 1 mg KOH/g oil and their miscibility under reservoir conditions (62 °C and 1700 psig) was tested in a sapphire PVT cell. The results verified the oil and gases were able to reach one single phase after contact time close to 9 hours, which meant no phase separation would occur during live oil coreflood as long as pore pressure was maintained above 1700 psig. After the miscibility test, live oil coreflood was carried out in porous media made of a 1-ft long reservoir core stack. This stack was first restored to the natural reduced reservoir environment following a thorough cleaning. Surfactant formulation screened based on phase behavior tests with dead crude showed remarkable aqueous solubility and interfacial tension reduction capability (solubilization ratio around 60 cc/cc). As low as 0.3% surfactant concentration was used in this coreflood. The injection of 0.3 PV ASP and 3.15 PV polymer recovered 44.5% original oil in place over waterflooding, which accounted for over 90% waterflooding residual oil. The analysis indicated ASP slug was injected at overoptimum salinity (live oil supposed to have a decreased optimum salinity compared to dead crude), which partially fitted the concept of negative salinity gradient that played a positive influence on oil displacement.

In this study, we investigated the influence of polymer retention (both irreversible and reversible retentions) on the unusually high resistance factor provided by hydrophobically associative polymers (AP) in porous media. As a comparison, a commercial partially hydrolyzed polyacrylamide (HPAM) was also tested. Coreflood or dynamic method was used to assess retention (both irreversible and reversible) and resistance factor in sandstone cores at a flux of around 11 ft/d. To make fair comparison, in some corefloods, HPAM solutions was injected in the same core after the completion of associative polymer injection cycle. The results indicated: (1) the retention of fresh associative polymer was nearly four times of that from fresh HPAM and this was indicated by the residual resistance factor measurement. Resistance factor provided by fresh associative polymer was almost ten times higher than that from HPAM even though they showed similar viscosity property in a viscometer; (2) Compared with fresh HPAM, a substantial excess reversible retention (44.6 μg/g rock) was detected for fresh associative polymer that was comparable to its irreversible retention (41.0 μg/g rock); (3) Degraded associative polymer showed reduced irreversible retention (32.7% less) and almost no reversible retention difference was observed between associative polymer and HPAM. The resistance factor by degraded associative polymer was almost half of that from fresh solution. In the absence of excess irreversible and reversible retentions caused by HPAM, the degraded associative still provided much higher resistance factor than HPAM; (4) The unusually high resistance factor from associative polymer could be ascribed to the irreversible retention that caused permeability reduction, reversible retention which provided resistance to polymer flow in porous media without affecting core permeability, and also the intermolecular association between hydrophobic monomers in associative polymer.

Scaling problems and complex produced fluid treatment are amongst the issues attributed to the use of alkali in Daqing chemical enhanced oil recovery (EOR) operations. These problems have incurred additional operating cost due to damage suffered by production/injection wells, surface facilities, and possibly the reservoir. This study presents the formulation of surfactant mixtures for chemical EOR in the absence of alkali by using combination of zwitterionic and anionic surfactants. The zwitterionic-anionic surfactant mixtures were formulated and screened based on aqueous stability, interfacial tension (IFT) measurement, and microemulsion phase behavior. Coreflood experiments were conducted to investigate recovery performance of the selected surfactant pair. Mixture of cocamidopropyl hydroxysultaine and alcohol propoxy sulfate outperformed other mixtures of zwitterionic and anionic surfactants investigated. This binary surfactant mixture appeared as a clear and transparent aqueous solution, achieved ultralow IFT in spinning-drop IFT measurement, and formed substantial middle-phase microemulsion in phase behavior test, indicating a synergistic behavior between the surfactant pair. The ultralow IFT achieved by the binary surfactant mixture led to displacement 63–75% of residual oil in place during coreflood experiments, for which the surfactant retention was around 0.08 mg/g rock. This result shows that zwitterionic-anionic surfactant mixture can provide an alternative approach toward optimizing chemical EOR processes without alkali.

This study focused on the influence of oil reactivity (ability to react with alkali to generate in situ surfactants) on salinity profile design during alkaline/surfactant/polymer (ASP) flooding. Two surrogate oils with different total acid number (TAN) were used. After determination of optimum salinity via phase behavior tests, 3 ASP corefloods with I-III-I, II-III-I (negative salinity gradient), and I-II-I salinity profiles were performed for each oil. ASP flooding was applied as a post-polymer enhanced oil recovery (EOR) method in this study. The results demonstrated: (1) for both low TAN oil and high TAN oil, when I-III-I salinity profile was employed, incremental oil recovery was less than 20% original oil in place (OOIP); (2) when negative salinity gradient was applied, high oil recovery from 33.5% to 38.5% OOIP was achieved over polymer flooding, resulting in cumulative recovery over 95% in spite of oil reactivity; (3) distinct trends were observed for corefloods with I-II-I salinity profile. For low TAN oil, an incremental recovery of only 20% OOIP was attained; by contrast, for high TAN oil, the incremental recovery was as high as 35.1%, which could be attributed to the generation of a large amount of in situ soaps that had lower optimum salinity compared to the added surfactants; and (4) ASP flooding proved to be an effective EOR approach to significantly reduce residual oil after polymer flooding if appropriate salinity profile was adopted. This study provides some guidance on salinity profile design when ASP flooding is considered for oils with different reactivity.

Hydrodynamic retention is one of the contributors to polymer loss in porous media. In this study, effects of flow rate, polymer molecular weight, and core permeability on hydrodynamic retention were investigated. To quantify hydrodynamic retention, injection of two identical polymer banks at different rates separated by 100 pore volumes of brine flushing was performed. Three HPAM polymers with molecular weights of 6–8 million, 12 million, and 20 million Daltons were tested in a 135 mD sandstone core and xanthan polymer with molecular weight of 2–2.5 million Daltons was tested in an 87 mD sandstone core. The retention of 6–8 million Daltons HPAM in a 1,650 mD sandstone core was also measured. Polymer retention in a fresh core was first measured at low injection rate of 3.11 ft/day. Then, 100 PV of 2% NaCl brine was injected to displace all the mobile polymer molecules in the core till pressure drop across the core became stable. Hydrodynamic retention at elevated flow rates was determined after the completion of retention at lower rates and comparisons with the initial polymer retention were made. Retention of 96.1 μg/g in the 135 mD core was detected for the 6–8 million HPAM at a flow rate of 3.11 ft/day. Increase of flow rate from 3.11 ft/day to 6.22 ft/day and 12.4 ft/day resulted in incremental retention of 2.27 μg/g and 5.38 μg/g, respectively. The injection of a higher molecular weight polymer at the same rate was performed after retention was satisfied with a lower molecular weight polymer. It was found the degree of hydrodynamic retention was greater when higher molecular weight polymers were injected. When core permeability was changed from 135 mD to 1,650 mD, both the initial and hydrodynamic retention were dramatically decreased. The initial retention of xanthan was 66.7 μg/g in an 87 mD sandstone core, which was smaller compared to the retention of HPAM in the similar core. However, hydrodynamic retention measurements of xanthan gives 3.26 μg/g and 6.38 μg/g increments with the increase of flow rate from 3.11 ft/day to 6.22 ft/day and 12.4 ft/day, which suggested that the retention of xanthan is slightly more sensitive to the change of injection rate than HPAM. This study also implied that measurement of residual resistance factor after polymer injection should be completed after sufficient brine flushing (around 100 PV), otherwise, an overestimated residual resistance factor might be provided.

The purpose of this research is to gain empirical evidence about the influence of firm size, leverage, systematic risk, and investment opportunity set on earnings response coefficient on manufacturing companies listed in Indonesia Stock Exchange for 2012-2014. Samples selected by using purposive sampling method. This research used a sample of one hundred fourty one manufacturing companies. The result of this research indicate that only systematic risk have an influence on earnings response coefficient while firm size, leverage, and investment opportunity set has not an influence on earnings response coefficient. For a better results, further research may add another variable that influence on earnings response coefficient.

Surfactant mixtures, consisting of commercially available zwitterionic and anionic surfactants, have been formulated at low-pH condition to obtain ultra-low interfacial tension (IFT). The surfactant systems show good interfacial performance during IFT measurements and subsequent phase behavior tests. The ultralow IFT (magnitude of 10-3 dynes/cm) is reached by formulating a mixed surfactant system that utilizes the synergism principle between a zwitterionic surfactant with amphoteric quality (amine oxide) and various anionic surfactants. Over 40 formulas with various surfactant species, surfactant ratio, pH, and salinity were screened. Screening process for the surfactant mixtures was based on IFT measurement using spinning drop tensiometer and qualitative assessment of solubility, followed by phase behavior tests. All the tests were done using dead crude oil sample and under low surfactant concentration (0.3 – 0.5 weight percent). Possible applications of this surfactant system, such as alkali-free chemical flooding and CO2-foam flooding, will be discussed.

The tendency of the existing infrastructure is not in accordance with the needs of the community because it is top down. Therefore, this study aims to assess community participation in managing community-based sanitation. Studies conducted focusing on participatory processes and the level of community participation in the provision of sanitation in the village program Mangunharjo precisely in RT 03 and 04 RW I. The method used in this research is quantitative and qualitative. The level of community participation in the management of the sanitation program has high participation category that has meaning on the degree of power-sharing community which has occurred rights, responsibilities and authority between the community and government to participate. Meanwhile, at the stage of organizing the participation category includes medium category (tokensm) in which the wishes of the people has been discussed, but the decision rests with the government. It is influenced by the role of the Village and Chairman of RT / RW is too dominant so that the public is not very enthusiastic in participating at the stage of organizing and resigned to the decision of the facilitator. Implementation of the program when viewed from the principle pelaksaaan almost matches that is about 80%, planning, implementation, and evaluation is fully in accordance with the principle only at the stage of organizing has obstacles described earlier which resulted in incompatibility in principle with the implementation of the program. That there is a relationship between the facilitator and community involvement, if the facilitator can perform their duties well as explaining the program well and excessive interference, then the public will enthusiastically participate. The Government needs to show its commitment in the implementation of the provision of community-based sanitation program (PSBM) in terms of giving people an opportunity to participate fully in sanitation management stages.