Pertiwi Andarani - Academia.edu (original) (raw)

Papers by Pertiwi Andarani

Polish Journal of Environmental Studies, Jul 10, 2024

International Journal of Sustainable Development and Planning, Dec 28, 2023

IOP Conference Series: Earth and Environmental Science, 2019

Energy demand rises significantly correlated to human activities in recent years. In contrary, en... more Energy demand rises significantly correlated to human activities in recent years. In contrary, energy supply from unrenewable resource decreases gradually from year to year. OMW as one of the renewable resources has not been expanded well in Indonesia. Therefore, SMFC will answer the alternative technology to generate electricity from OMW. The objectives of this study are conducted to compare of waste volumes on power generation and COD removal in SMFC and determine the optimum waste volume for SMFC application affected by river sediment microorganism source and mixed waste type. SMFC reactor as MFC single chamber was designed by 2.5-liter volume of plastic houseware utilized with single graphene anode and cathode to increase the power generation. The waste volume as the independent variable was adjusted 1/3; 1/2; 2/3 of the 2.5- liter volume of SMFC reactor, whereas river sediment microorganism source and mixed waste were dependent variables. The power density and COD removal perce...

Acadlore Transactions on Geosciences

Escalating issues pertaining to the disposal of plastic waste have emerged as an alarming global ... more Escalating issues pertaining to the disposal of plastic waste have emerged as an alarming global concern, underscored by the environmental infiltration of fragmented plastic materials into terrestrial, aquatic, and atmospheric systems. This predicament is notably amplified within the African continent, where rudimentary waste management infrastructures exacerbate the situation. This review dissects the prevalence, abundance, and distribution of plastic litter and microplastics within diverse environmental compartments (namely, sediments, water bodies, and biota) across Africa. Detailed analysis of existing research findings highlights concentrations of plastic debris and microplastics, identifying the predominant types of polymers and shapes of particles present. It is observed that most African research endeavours have primarily concentrated on microplastics, albeit macroplastics or plastic litter posing substantial challenges as well. Marine environments have been the predominant focus of these studies, with freshwater ecosystems relatively understudied. The geographical focal points of these research efforts were primarily South Africa, Tunisia, and Nigeria. Conversely, a glaring lack of comprehensive studies addressing plastic pollution within terrestrial and atmospheric systems calls for urgent research attention. Documented evidence of plastic ingestion by diverse aquatic and terrestrial fauna, including insects, fish, birds, molluscs, and arthropods, reaffirms the pervasive nature of the problem within African water bodies. An evaluation of existing literature identifies polyester, polyethylene, and polypropylene as the most common types of plastics present within both freshwater and coastal systems. Unfortunately, a significant proportion of these studies failed to adequately characterize the identified plastics, thus obstructing the identification of potential sources. Consequently, it is imperative that future investigations prioritize polymer identification, which can facilitate the development and implementation of efficacious strategies for mitigating plastic pollution and curtailing environmental leakage of plastics.

Communications in science and technology, Jul 11, 2023

This paper presents the effect of microwave and ultrasound irradiation on the enzymatic hydrolysi... more This paper presents the effect of microwave and ultrasound irradiation on the enzymatic hydrolysis of water hyacinth biomass in the presence of surfactants. Prior to hydrolyzing, the water hyacinth was treated utilizing alkali with and without microwave assistance. It was revealed that the microwave improved the removal of lignin and hemicellulose. The treated water hyacinth biomass was also characterized using Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), and Fourier-Transform Infrared (FT-IR) Spectroscopy. The effect of surfactant and the assistance of microwave and ultrasound were comprehensively studied. Some parameters varied, including stirring speed, surfactant type, concentration, and reaction time. The results indicated that microwave and ultrasound could enhance the reaction rate. Tween 80 here could improve conventional, microwave-assisted, and ultrasound-assisted hydrolysis of water hyacinth biomass. It was found that the ultrasoundassisted hydrolysis was better than that of others. The results of this research can be used as the groundwork for further developing the lignocellulosic biomass hydrolysis process, especially in an advanced enzymatic hydrolysis process.

Japan Society of Civil Engineers eBooks, May 15, 2020

Journal of Ecological Engineering

The presence of microplastic pollution in coastal areas has garnered attention due to its detrime... more The presence of microplastic pollution in coastal areas has garnered attention due to its detrimental impact on aquatic ecosystems and human health. In this study, our objective was to identify and characterize microplastics in the Banger River area of Pekalongan City, which is known for its numerous industrial activities, particularly batik small-medium industries. The extraction process involved filtration, drying, wet peroxide oxidation, density separation using NaI, and identification of microplastic particles. The shape, color, and size of the particles were characterized using a stereo microscope, while Fourier Transform Infra-Red Spectrometer and the hot needle method were employed for chemical structure analysis. Given that rivers serve as primary conduits for waste transport from land to sea, we conducted sampling at different times of the day. Our findings revealed an average of 0.61 ± 0.47 particles/m 3 in the morning, 0.59 ± 0.67 particles/m 3 in the afternoon, and 0.10 ± 0.02 particles/m 3 in the evening. Among the microplastic polymers analyzed, we successfully identified polypropylene as one of the two predominant types. To establish a baseline for mitigating the release of plastic waste and microplastic residues into the environment, long-term monitoring is essential to evaluate the flow of plastic waste and microplastics from Indonesian rivers to the oceans.

IOP Conference Series: Earth and Environmental Science

Zinc is frequently reacting with inorganic species in water to form zinc species. Thus, the chemi... more Zinc is frequently reacting with inorganic species in water to form zinc species. Thus, the chemical speciation of Zinc in the aquatic environment has become a significant concern nowadays due to its adverse effect on humans and its potential toxicity in the water system. In this study, to investigate the interaction between dissolved zinc and hydro-chemical factors and to estimate the Zn speciation form, samples of river water were collected spatially from the Umeda River mainstream and tributaries in different seasons for one year. The hydrochemistry and dissolved zinc pollution characteristics of the samples were analyzed. Zn speciation was assessed by PHREEQC simulation. The result show that the main form of Zn speciation was Zinc free ion (Zn2+) in all seasons. However, in summer and spring season, the ZnCO3 and ZnOH+ concentration was higher than the other season. These speciation form may be attributed to the activities around the river in different season according to the si...

IOP Conference Series: Earth and Environmental Science

Indonesia has established a national action plan on marine plastic debris to tackle the issue of ... more Indonesia has established a national action plan on marine plastic debris to tackle the issue of marine plastic debris. Because most of the marine plastic debris in Indonesia is likely due to mismanaged plastic waste, it is important to address the problem of riverine plastic river problem in Indonesia. The objectives of this study are to visually observe the condition of the river in terms of plastic pollution, to quantify plastic litter in the river, and to develop a visual counting model of plastic litter quantification. The visual counting of plastic debris (> 2.5 cm) method based on the European standard method was applied to a river in Indonesia. The main challenge was the high turbidity of the water that obstructed visual observation. The deployment of the fishing net was also not appropriate to collect debris. Most of the plastic debris was stranded on the riverbanks, indicating that the plastic flow was likely elevated due to runoff during the rainy season. Four types of...

E3S Web of Conferences, 2018

An environmentally sound management of plastic waste in Semarang City is necessary due to increas... more An environmentally sound management of plastic waste in Semarang City is necessary due to increasing plastic waste generation; limited capacity of Jatibarang Final Disposal; dangers of open burning of plastic waste; pollution of water resources both surface water and sea water; and limited amount of raw materials for the manufacture of plastic resin. This study aims to present the assessment of plastic waste management from collection to final disposal as well as its estimated generation. A field study was conducted to identify the material flow of plastic waste, particularly PET bottles. To estimate the potential generation of plastic waste, a top-down approach was used. The volume of plastic waste in Semarang reached 16.28% of the total municipal waste, in which the highest part of inorganic waste. The total estimated plastic waste generation in Semarang City, particularly from households, was 1012.486 m3/day. There is an urgent need for improving the plastic management in Semaran...

Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan

Noise may cause serious health problems, including physiological responses, specifically in the c... more Noise may cause serious health problems, including physiological responses, specifically in the cardiovascular system. This study aims to assess occupational noise exposure and analyze the correlation between occupational noise and blood pressure in cabin and station personnel. The participants were 30 cabin personnel (train drivers) and 30 station personnel. The cabin had a Leq of 90.3 dBA while the noise level at Poncol Station was still below the threshold limit value (TLV), i.e., 75.8 dBA. The noise exposure assessment also included noise exposure profiling. The Chi-square test showed that noise influenced systolic and diastolic blood pressure changes. Furthermore, for train drivers, the t-test showed a difference in systolic and diastolic between before and after the activity. As for station personnel, there was a difference in systolic, but contrarily it was not the case in diastolic. According to the noise profile, the train whistle had the most significant noise level at 120...

Marine Pollution Bulletin

Zinc (Zn) is crucial for life and plays a vital part in organisms' biological activities (humans,... more Zinc (Zn) is crucial for life and plays a vital part in organisms' biological activities (humans, animals, and plants). Zn, the fourth-most frequent metal in usage, is widely used in the industrial sector to create products. Zn is the third-most produced non-ferrous metal in Japan and the thirdmost released chemical in water bodies. Zn has become one of the most critical considerations concerning worldwide water quality, including in Japan, with the role of preserving aquatic life. Since 2003, the Japanese Ministry of the Environment has established an environmental quality standard (EQS) for Zn in surface water (0.030 mg/L) to conserve aquatic life. However, multiple Japanese rivers still could not comply with the EQS in 2019. Therefore, this study aimed to assess the spatial and temporal variation and the source identification of Zn in near-neutral rivers. This study was conducted in two rivers, affected mainly by urban areas (manufacturing industries) and agriculture located in the vicinity of Aizumame River and the Umeda River, Aichi, Japan. This study consisted of three survey types, i.e., monthly baseflow survey (on sunny days), hourly baseflow survey (on sunny days during weekday and weekend), and hourly stormflow survey (during a rain event). The monthly baseflow survey and the hourly baseflow survey were undertaken in the Aizumame River and the Umeda River. Because a further investigation of the possible Zn source and the underlying factors of the Zn variability was needed, more detailed water parameter measurement was conducted in the Umeda River. Water parameters [Zn, Fe (iron), particulate organic carbon (POC), temperature, pH, electroconductivity, cations, and anions] and riverbed sediments (Zn, Fe, and POC in fine sand, medium sand, and coarse sand) were measured accordingly. The metal content was measured using atomic absorption spectrometry. Hierarchical cluster analysis (HCA), flow analysis, pearson correlation, principal component factor loading analysis (PCFA), load and discharge curve (L-Q model), and end member mixing analysis (EMMA) were performed to assess the association among the parameters and to identify the potential Zn sources. In the Aizumame River, at the two downstream sampling stations (A4 = 0.059 mg/L; A5 = 0.055 mg/L), the EQS was breached in 2017. Zn levels considerably varied from undetected to 0.139 mg/L. Throughout the year, Zn concentrations along the Umeda River fluctuated in spatial and temporal, ranging from 0.002 to 0.090 mg/L. At the most downstream part of the Umeda River, the annual mean concentration value of 0.031 mg/L exceeded the EQS. Anthropogenic activities have likely influenced the riverine Zn levels in Umeda River. In the name of Allah SWT, the most gracious the most merciful It is a genuine pleasure to express my deep sense of gratitude to our honorable laboratory head, Prof. Takanobu Inoue for his excellent guidance, providing many invaluable experiences and opportunities, and kind supports during my PhD study. His meticulous scrutiny, timely advice, scholarly advice and scientific approach have helped me to accomplish this work. Similarly, sincere gratitude goes to my supervisor Assoc. Prof. Dr. Kuriko Yokota for the support and guidance to achieve the study's objectives. I also would like to thank Prof. Shigeru Kato for the constructive comments and suggestion which greatly improved this dissertation. I am grateful to other members: Dr. Makoto Saga who sacrificed his time to guide me performing analytical procedures using atomic absorption spectroscopy; and Assist. Prof. Dr. Nguyen Minh Ngoc for her kind support and guidance to conduct particulate organic carbon measurements. I am really grateful to the Japanese Ministry of Education, Culture, Sports, Science, and Technology (MEXT) for the PhD scholarship which gave me opportunities to conduct research that I always dream of. I would like to thank the Diponegoro University Board and my colleagues at Department of Environmental Engineering (Faculty of Engineering) for the endorsement and encouragement. I sincerely thank my colleagues in the Water Environment Conservation Engineering Laboratory. Special mention to Hardianti Alimuddin for her dedication to accomplish the laboratory works and Moliya Nurmalisa for her useful advice and huge supports. I would like to thank Widyastuti, Aemilia, Samim, and Suzuki for a part of sampling and laboratory works;

CLEAN – Soil, Air, Water, 2022

2016 2nd International Conference of Industrial, Mechanical, Electrical, and Chemical Engineering (ICIMECE), 2016

One of the automotive design car developments is speedometer position change. There are two speed... more One of the automotive design car developments is speedometer position change. There are two speedometer positions used by the public, i.e. in behind the steer and on the center of dashboard. Speedometer position affects the visual scanning time information on the speedometer (glance). Total Time glances are very influential to distraction and workload while driving. The purpose of this study is to determine the position of the speedometer that minimizes distraction and workload while driving. The type of this research is a real experimental study using real cars on the road. The number of respondents involved was 12 peoples. Distraction data were obtained from the total glances while driving (using cameras). While the workload while driving was obtained from a questionnaire adapted from DALI (Driving Load Activity Index). Based on the analysis of total glances and questionnaires, speedometer on the center of dashboard showed a higher total glances and higher average value of global ...

Bad weather is one of the factors that cause traffic accidents. Accidents happen because visibili... more Bad weather is one of the factors that cause traffic accidents. Accidents happen because visibility decreases when bad weather occurs. In order to prevent accidents, roads need to be installed traffic signs. One type of traffic sign is a Variable Speed Limit (VSL). In this study, the relationship between driver compliance and VSL (when driver's visibility is reduced) is measured and analyzed. Primary data was collected by filling out a closed questionnaire with a Likert scale of 1-5. The total respondents in this study are 130 people who have passed the Banyumanik-Bawen toll road. Primary data in this research is analyzed by Structural Equation Modeling (SEM) method. The first result, human factor and VSL satisfaction are significant to driver compliance during any weather conditions. The second result, driver compliance during fog or mild rainy weather conditions, is only influenced by human factors. In conclusion, when bad weather conditions human factors and satisfaction with...

Water Supply, 2022

Heavy metal contamination in the urban river has become the most severe problem in the urban envi... more Heavy metal contamination in the urban river has become the most severe problem in the urban environment, especially zinc (Zn) compound is harmful to the environment at current levels of exposure. This study aims to assess the impact of urbanization and industrialization to Zn pollution in surface sediment at the Umeda River. Triplicate surface sediment samples were collected at 9 sample points. Atomic Absorption Spectrophotometer (AAS) was used for analyzing the Zn and Fe concentrations. The surface sediments in the Umeda River contained 48–159 mg/kg of Zn. The results indicated that Zn concentrations were abundant in the ascending order of 600–1,000 μm, 300–600 μm, and smaller than 300 μm. The higher the grain size, the higher the POC in which might contribute to the higher Zn and Fe concentration. In addition, the sediment quality guidelines indicated that the Zn levels in the study area did not constitute a major threat to biota. Normalization with Fe showed that the Zn pollutio...

Limbah cair elektroplating mengandung berbagai logam berat, senyawa organik dan juga anorganik. L... more Limbah cair elektroplating mengandung berbagai logam berat, senyawa organik dan juga anorganik. Limbah yang langsung dibuang ke lingkungan akan menyebabkan penurunan kualitas lingkungan dan akan membahayakan makhluk hidup. Untuk itu perlu adanya pengolahan terhadap limbah elektroplating. Penelitian ini bertujuan untuk menganalisis kemampuan tumbuhan kayu apu (Pistia stratiotes L.) dalam menyisihkan kromium total dan COD limbah elektroplating. Penelitian ini dilakukan dengan sistem batch tertutup dengan variasi jumlah tumbuhan (2, 4, 6 tumbuhan) dan waktu tinggal (3, 6, 9, 12, 15 hari). Karakteristik awal limbah elektroplating pada penelitian ini yaitu kromium total 1,9784 mg/l dan COD 38,105 mg/l. Efisiensi penyisihan kromium total terjadi pada reaktor enam tumbuhan yaitu sebesar 95,01% hingga konsentrasi menjadi 0,0987 mg/l. Sedangkan efisiensi penyisihan COD terjadi pada reaktor kontrol sebesar 50,41% dengan konsentrasi akhir 18,89 mg/l. Fitoremediasi limbah elektroplating dapat d...

Polish Journal of Environmental Studies, Jul 10, 2024

International Journal of Sustainable Development and Planning, Dec 28, 2023

IOP Conference Series: Earth and Environmental Science, 2019

Energy demand rises significantly correlated to human activities in recent years. In contrary, en... more Energy demand rises significantly correlated to human activities in recent years. In contrary, energy supply from unrenewable resource decreases gradually from year to year. OMW as one of the renewable resources has not been expanded well in Indonesia. Therefore, SMFC will answer the alternative technology to generate electricity from OMW. The objectives of this study are conducted to compare of waste volumes on power generation and COD removal in SMFC and determine the optimum waste volume for SMFC application affected by river sediment microorganism source and mixed waste type. SMFC reactor as MFC single chamber was designed by 2.5-liter volume of plastic houseware utilized with single graphene anode and cathode to increase the power generation. The waste volume as the independent variable was adjusted 1/3; 1/2; 2/3 of the 2.5- liter volume of SMFC reactor, whereas river sediment microorganism source and mixed waste were dependent variables. The power density and COD removal perce...

Acadlore Transactions on Geosciences

Escalating issues pertaining to the disposal of plastic waste have emerged as an alarming global ... more Escalating issues pertaining to the disposal of plastic waste have emerged as an alarming global concern, underscored by the environmental infiltration of fragmented plastic materials into terrestrial, aquatic, and atmospheric systems. This predicament is notably amplified within the African continent, where rudimentary waste management infrastructures exacerbate the situation. This review dissects the prevalence, abundance, and distribution of plastic litter and microplastics within diverse environmental compartments (namely, sediments, water bodies, and biota) across Africa. Detailed analysis of existing research findings highlights concentrations of plastic debris and microplastics, identifying the predominant types of polymers and shapes of particles present. It is observed that most African research endeavours have primarily concentrated on microplastics, albeit macroplastics or plastic litter posing substantial challenges as well. Marine environments have been the predominant focus of these studies, with freshwater ecosystems relatively understudied. The geographical focal points of these research efforts were primarily South Africa, Tunisia, and Nigeria. Conversely, a glaring lack of comprehensive studies addressing plastic pollution within terrestrial and atmospheric systems calls for urgent research attention. Documented evidence of plastic ingestion by diverse aquatic and terrestrial fauna, including insects, fish, birds, molluscs, and arthropods, reaffirms the pervasive nature of the problem within African water bodies. An evaluation of existing literature identifies polyester, polyethylene, and polypropylene as the most common types of plastics present within both freshwater and coastal systems. Unfortunately, a significant proportion of these studies failed to adequately characterize the identified plastics, thus obstructing the identification of potential sources. Consequently, it is imperative that future investigations prioritize polymer identification, which can facilitate the development and implementation of efficacious strategies for mitigating plastic pollution and curtailing environmental leakage of plastics.

Communications in science and technology, Jul 11, 2023

This paper presents the effect of microwave and ultrasound irradiation on the enzymatic hydrolysi... more This paper presents the effect of microwave and ultrasound irradiation on the enzymatic hydrolysis of water hyacinth biomass in the presence of surfactants. Prior to hydrolyzing, the water hyacinth was treated utilizing alkali with and without microwave assistance. It was revealed that the microwave improved the removal of lignin and hemicellulose. The treated water hyacinth biomass was also characterized using Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), and Fourier-Transform Infrared (FT-IR) Spectroscopy. The effect of surfactant and the assistance of microwave and ultrasound were comprehensively studied. Some parameters varied, including stirring speed, surfactant type, concentration, and reaction time. The results indicated that microwave and ultrasound could enhance the reaction rate. Tween 80 here could improve conventional, microwave-assisted, and ultrasound-assisted hydrolysis of water hyacinth biomass. It was found that the ultrasoundassisted hydrolysis was better than that of others. The results of this research can be used as the groundwork for further developing the lignocellulosic biomass hydrolysis process, especially in an advanced enzymatic hydrolysis process.

Japan Society of Civil Engineers eBooks, May 15, 2020

Journal of Ecological Engineering

The presence of microplastic pollution in coastal areas has garnered attention due to its detrime... more The presence of microplastic pollution in coastal areas has garnered attention due to its detrimental impact on aquatic ecosystems and human health. In this study, our objective was to identify and characterize microplastics in the Banger River area of Pekalongan City, which is known for its numerous industrial activities, particularly batik small-medium industries. The extraction process involved filtration, drying, wet peroxide oxidation, density separation using NaI, and identification of microplastic particles. The shape, color, and size of the particles were characterized using a stereo microscope, while Fourier Transform Infra-Red Spectrometer and the hot needle method were employed for chemical structure analysis. Given that rivers serve as primary conduits for waste transport from land to sea, we conducted sampling at different times of the day. Our findings revealed an average of 0.61 ± 0.47 particles/m 3 in the morning, 0.59 ± 0.67 particles/m 3 in the afternoon, and 0.10 ± 0.02 particles/m 3 in the evening. Among the microplastic polymers analyzed, we successfully identified polypropylene as one of the two predominant types. To establish a baseline for mitigating the release of plastic waste and microplastic residues into the environment, long-term monitoring is essential to evaluate the flow of plastic waste and microplastics from Indonesian rivers to the oceans.

IOP Conference Series: Earth and Environmental Science

Zinc is frequently reacting with inorganic species in water to form zinc species. Thus, the chemi... more Zinc is frequently reacting with inorganic species in water to form zinc species. Thus, the chemical speciation of Zinc in the aquatic environment has become a significant concern nowadays due to its adverse effect on humans and its potential toxicity in the water system. In this study, to investigate the interaction between dissolved zinc and hydro-chemical factors and to estimate the Zn speciation form, samples of river water were collected spatially from the Umeda River mainstream and tributaries in different seasons for one year. The hydrochemistry and dissolved zinc pollution characteristics of the samples were analyzed. Zn speciation was assessed by PHREEQC simulation. The result show that the main form of Zn speciation was Zinc free ion (Zn2+) in all seasons. However, in summer and spring season, the ZnCO3 and ZnOH+ concentration was higher than the other season. These speciation form may be attributed to the activities around the river in different season according to the si...

IOP Conference Series: Earth and Environmental Science

Indonesia has established a national action plan on marine plastic debris to tackle the issue of ... more Indonesia has established a national action plan on marine plastic debris to tackle the issue of marine plastic debris. Because most of the marine plastic debris in Indonesia is likely due to mismanaged plastic waste, it is important to address the problem of riverine plastic river problem in Indonesia. The objectives of this study are to visually observe the condition of the river in terms of plastic pollution, to quantify plastic litter in the river, and to develop a visual counting model of plastic litter quantification. The visual counting of plastic debris (> 2.5 cm) method based on the European standard method was applied to a river in Indonesia. The main challenge was the high turbidity of the water that obstructed visual observation. The deployment of the fishing net was also not appropriate to collect debris. Most of the plastic debris was stranded on the riverbanks, indicating that the plastic flow was likely elevated due to runoff during the rainy season. Four types of...

E3S Web of Conferences, 2018

An environmentally sound management of plastic waste in Semarang City is necessary due to increas... more An environmentally sound management of plastic waste in Semarang City is necessary due to increasing plastic waste generation; limited capacity of Jatibarang Final Disposal; dangers of open burning of plastic waste; pollution of water resources both surface water and sea water; and limited amount of raw materials for the manufacture of plastic resin. This study aims to present the assessment of plastic waste management from collection to final disposal as well as its estimated generation. A field study was conducted to identify the material flow of plastic waste, particularly PET bottles. To estimate the potential generation of plastic waste, a top-down approach was used. The volume of plastic waste in Semarang reached 16.28% of the total municipal waste, in which the highest part of inorganic waste. The total estimated plastic waste generation in Semarang City, particularly from households, was 1012.486 m3/day. There is an urgent need for improving the plastic management in Semaran...

Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan

Noise may cause serious health problems, including physiological responses, specifically in the c... more Noise may cause serious health problems, including physiological responses, specifically in the cardiovascular system. This study aims to assess occupational noise exposure and analyze the correlation between occupational noise and blood pressure in cabin and station personnel. The participants were 30 cabin personnel (train drivers) and 30 station personnel. The cabin had a Leq of 90.3 dBA while the noise level at Poncol Station was still below the threshold limit value (TLV), i.e., 75.8 dBA. The noise exposure assessment also included noise exposure profiling. The Chi-square test showed that noise influenced systolic and diastolic blood pressure changes. Furthermore, for train drivers, the t-test showed a difference in systolic and diastolic between before and after the activity. As for station personnel, there was a difference in systolic, but contrarily it was not the case in diastolic. According to the noise profile, the train whistle had the most significant noise level at 120...

Marine Pollution Bulletin

Zinc (Zn) is crucial for life and plays a vital part in organisms' biological activities (humans,... more Zinc (Zn) is crucial for life and plays a vital part in organisms' biological activities (humans, animals, and plants). Zn, the fourth-most frequent metal in usage, is widely used in the industrial sector to create products. Zn is the third-most produced non-ferrous metal in Japan and the thirdmost released chemical in water bodies. Zn has become one of the most critical considerations concerning worldwide water quality, including in Japan, with the role of preserving aquatic life. Since 2003, the Japanese Ministry of the Environment has established an environmental quality standard (EQS) for Zn in surface water (0.030 mg/L) to conserve aquatic life. However, multiple Japanese rivers still could not comply with the EQS in 2019. Therefore, this study aimed to assess the spatial and temporal variation and the source identification of Zn in near-neutral rivers. This study was conducted in two rivers, affected mainly by urban areas (manufacturing industries) and agriculture located in the vicinity of Aizumame River and the Umeda River, Aichi, Japan. This study consisted of three survey types, i.e., monthly baseflow survey (on sunny days), hourly baseflow survey (on sunny days during weekday and weekend), and hourly stormflow survey (during a rain event). The monthly baseflow survey and the hourly baseflow survey were undertaken in the Aizumame River and the Umeda River. Because a further investigation of the possible Zn source and the underlying factors of the Zn variability was needed, more detailed water parameter measurement was conducted in the Umeda River. Water parameters [Zn, Fe (iron), particulate organic carbon (POC), temperature, pH, electroconductivity, cations, and anions] and riverbed sediments (Zn, Fe, and POC in fine sand, medium sand, and coarse sand) were measured accordingly. The metal content was measured using atomic absorption spectrometry. Hierarchical cluster analysis (HCA), flow analysis, pearson correlation, principal component factor loading analysis (PCFA), load and discharge curve (L-Q model), and end member mixing analysis (EMMA) were performed to assess the association among the parameters and to identify the potential Zn sources. In the Aizumame River, at the two downstream sampling stations (A4 = 0.059 mg/L; A5 = 0.055 mg/L), the EQS was breached in 2017. Zn levels considerably varied from undetected to 0.139 mg/L. Throughout the year, Zn concentrations along the Umeda River fluctuated in spatial and temporal, ranging from 0.002 to 0.090 mg/L. At the most downstream part of the Umeda River, the annual mean concentration value of 0.031 mg/L exceeded the EQS. Anthropogenic activities have likely influenced the riverine Zn levels in Umeda River. In the name of Allah SWT, the most gracious the most merciful It is a genuine pleasure to express my deep sense of gratitude to our honorable laboratory head, Prof. Takanobu Inoue for his excellent guidance, providing many invaluable experiences and opportunities, and kind supports during my PhD study. His meticulous scrutiny, timely advice, scholarly advice and scientific approach have helped me to accomplish this work. Similarly, sincere gratitude goes to my supervisor Assoc. Prof. Dr. Kuriko Yokota for the support and guidance to achieve the study's objectives. I also would like to thank Prof. Shigeru Kato for the constructive comments and suggestion which greatly improved this dissertation. I am grateful to other members: Dr. Makoto Saga who sacrificed his time to guide me performing analytical procedures using atomic absorption spectroscopy; and Assist. Prof. Dr. Nguyen Minh Ngoc for her kind support and guidance to conduct particulate organic carbon measurements. I am really grateful to the Japanese Ministry of Education, Culture, Sports, Science, and Technology (MEXT) for the PhD scholarship which gave me opportunities to conduct research that I always dream of. I would like to thank the Diponegoro University Board and my colleagues at Department of Environmental Engineering (Faculty of Engineering) for the endorsement and encouragement. I sincerely thank my colleagues in the Water Environment Conservation Engineering Laboratory. Special mention to Hardianti Alimuddin for her dedication to accomplish the laboratory works and Moliya Nurmalisa for her useful advice and huge supports. I would like to thank Widyastuti, Aemilia, Samim, and Suzuki for a part of sampling and laboratory works;

CLEAN – Soil, Air, Water, 2022

2016 2nd International Conference of Industrial, Mechanical, Electrical, and Chemical Engineering (ICIMECE), 2016

One of the automotive design car developments is speedometer position change. There are two speed... more One of the automotive design car developments is speedometer position change. There are two speedometer positions used by the public, i.e. in behind the steer and on the center of dashboard. Speedometer position affects the visual scanning time information on the speedometer (glance). Total Time glances are very influential to distraction and workload while driving. The purpose of this study is to determine the position of the speedometer that minimizes distraction and workload while driving. The type of this research is a real experimental study using real cars on the road. The number of respondents involved was 12 peoples. Distraction data were obtained from the total glances while driving (using cameras). While the workload while driving was obtained from a questionnaire adapted from DALI (Driving Load Activity Index). Based on the analysis of total glances and questionnaires, speedometer on the center of dashboard showed a higher total glances and higher average value of global ...

Bad weather is one of the factors that cause traffic accidents. Accidents happen because visibili... more Bad weather is one of the factors that cause traffic accidents. Accidents happen because visibility decreases when bad weather occurs. In order to prevent accidents, roads need to be installed traffic signs. One type of traffic sign is a Variable Speed Limit (VSL). In this study, the relationship between driver compliance and VSL (when driver's visibility is reduced) is measured and analyzed. Primary data was collected by filling out a closed questionnaire with a Likert scale of 1-5. The total respondents in this study are 130 people who have passed the Banyumanik-Bawen toll road. Primary data in this research is analyzed by Structural Equation Modeling (SEM) method. The first result, human factor and VSL satisfaction are significant to driver compliance during any weather conditions. The second result, driver compliance during fog or mild rainy weather conditions, is only influenced by human factors. In conclusion, when bad weather conditions human factors and satisfaction with...

Water Supply, 2022

Heavy metal contamination in the urban river has become the most severe problem in the urban envi... more Heavy metal contamination in the urban river has become the most severe problem in the urban environment, especially zinc (Zn) compound is harmful to the environment at current levels of exposure. This study aims to assess the impact of urbanization and industrialization to Zn pollution in surface sediment at the Umeda River. Triplicate surface sediment samples were collected at 9 sample points. Atomic Absorption Spectrophotometer (AAS) was used for analyzing the Zn and Fe concentrations. The surface sediments in the Umeda River contained 48–159 mg/kg of Zn. The results indicated that Zn concentrations were abundant in the ascending order of 600–1,000 μm, 300–600 μm, and smaller than 300 μm. The higher the grain size, the higher the POC in which might contribute to the higher Zn and Fe concentration. In addition, the sediment quality guidelines indicated that the Zn levels in the study area did not constitute a major threat to biota. Normalization with Fe showed that the Zn pollutio...

Limbah cair elektroplating mengandung berbagai logam berat, senyawa organik dan juga anorganik. L... more Limbah cair elektroplating mengandung berbagai logam berat, senyawa organik dan juga anorganik. Limbah yang langsung dibuang ke lingkungan akan menyebabkan penurunan kualitas lingkungan dan akan membahayakan makhluk hidup. Untuk itu perlu adanya pengolahan terhadap limbah elektroplating. Penelitian ini bertujuan untuk menganalisis kemampuan tumbuhan kayu apu (Pistia stratiotes L.) dalam menyisihkan kromium total dan COD limbah elektroplating. Penelitian ini dilakukan dengan sistem batch tertutup dengan variasi jumlah tumbuhan (2, 4, 6 tumbuhan) dan waktu tinggal (3, 6, 9, 12, 15 hari). Karakteristik awal limbah elektroplating pada penelitian ini yaitu kromium total 1,9784 mg/l dan COD 38,105 mg/l. Efisiensi penyisihan kromium total terjadi pada reaktor enam tumbuhan yaitu sebesar 95,01% hingga konsentrasi menjadi 0,0987 mg/l. Sedangkan efisiensi penyisihan COD terjadi pada reaktor kontrol sebesar 50,41% dengan konsentrasi akhir 18,89 mg/l. Fitoremediasi limbah elektroplating dapat d...