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The liquid radioactive waste generated by the G.A. Siwabessy reactor (RSG-GAS) is categorized into low-activity liquid radwaste (LALR) and medium-activity liquid radwaste (MALR). The radionuclide content of both LALR and MALR can use as an indicator of the structural integrity of the reactor’s systems, structures, and components (SSC). To evaluate the degradation of the reactor SSC, the radionuclide species were identified, and their activities were measured using gamma spectroscopy. Based on the identified radionuclides, the process of their formation can be traced. The radionuclides identified in LALR were 24Na, 51Cr, 59Fe, 60Co, 65Zn, and 124Sb, while the radionuclides in MALR were 24Na, 51Cr, 58Co, 59Fe, 60Co, 65Ni, 65Zn, 89Kr, 90Kr, 109Cd, 131I, 132I, 140Ba, 137Cs, 146Ce, and several others. The radionuclides found can be classified into corrosion product activation (60Co, 65Zn, 51Cr, 59Fe, 24Na, 65Ni), topaz impurities activation (51Cr, 59Fe, 60Co, 65Zn), fission product (90Kr, 140Ba, 131I, 137Cs, etc.), and demineralized water impurities activation (51Cr, 59Fe, 65Zn, 60Co, etc.). After comparing the activity value of each radionuclide with the limit value in the safety analysis report document, we can conclude that the activity of each one is below the required level. It can infer that the structural integrity of reactor SSC is still well maintain. During routine monitoring, the radionuclide content in the primary coolant fluctuates depending on the reactor load. The concentration of radionuclides detected varies when a large or small number of research samples are loaded onto the core. Nevertheless, their activities remain within the required safety limits.

This study focused on the influence of cash turnover, receivables turnover, and inventory turnover against the Net Profit Margin (NPM), showing the inequality of the results of previous studies. Therefore, this research investigates whether that inequality is associated with cash turnover, receivables turnover, and supply turnover against NPM, which becomes the focus of this study. The research used the data obtained from food and beverage manufacturing subsectors in the Southeast Asian Stock Exchange between 2012 and 2018. This study applied purposive sampling of 11 companies that provided a complete financial report, acquiring 77 samples. The statistical analyses used were multiple linear regression, partial testing, and simultaneous testing. The results of this study indicated that cash turnover and receivables turnover had no significant influence on the NPM, while the supply turnover had a significant influence on NPM. The results of the simulta-neous study of cash turnover, the turnover of receivables, and inventory turnover have a signif-icant rate of 0.010 < 0.05. It can be concluded that cash turnover, turnover receivables, and inventory rotation significantly influence the NPM.

Hydroponic is a farming method that utilizes water, minerals, and oxygen. This study aims to find out the best nutrition towards growing curly lettuce (Lactuca sativa L.) by using the NFT (nutrient film technique) hydroponic system integrated with sensors to measure EC concentration of nutrients, pH acidity, and RH air humidity. This study also incorporates a grouped randomized design with two nutritional treatment (code P1 and P2), with 20 replication. The results showed that nutrition P1 producing a better variable compared to nutrition P2 in terms of plant length, quantity of leaves, length of root, total mass of fresh plants, total mass of plant crown, total mass of fresh roots, and chlorophyl content. Key words: NFT hydroponic system, nutrition, curly lettuce

The objective of this research is to understand the condition of the structural material of the 30 MW RSG-GAS research reactor as input for the aging management program. Furthermore, this should enable a prediction of the remaining life of the components. In the current experiment, corrosion surveillance was carried out at Interim Storage for Spent Fuel (ISSF), that has similar water quality as in reactor pool by using a corrosion probe which is made of aluminum alloy and stainless steel. The probe set is designed to understand the effect of water quality in the ISSF pond. The corrosion processes observed were pitting, crevice and galvanic corrosion. Two sets of corrosion probes were immersed into the ISSF pool in 2007, hanging by steel wire, 1-meter height from the bottom surface. One probe set consists of horizontal and vertical positions. The soaking time was 7 years. The observations made were water chemical content, corrosion rate and visual analysis, macro and micro. For macro visual observations an optical microscope was used, for micro-observations SEM-EDX. From the results of macro-observations, information on the presence of galvanic corrosion, crevice and pitting was obtained. SEM-EDX provides information on the influence of chloride ions on corrosion products. This experience will be very useful in dealing with the aging process of Indonesia’s nuclear power plants in the future.

The development of tourism at Borobudur Temple has caused substantial environmental, economic, social, and cultural impacts. Therefore, it is crucial to establish a path toward a sustainable way to conduct tourism of this site. Previous studies have focused on local communities as a key player in the sustainable tourism development process. This study seeks to address the local visitors' perspective and assess their support for sustainable tourism development. Research data were collected from previous local visitors to Borobudur Temple. Of the 340 respondents to the online survey questionnaire, 267 met the criteria. We tested our hypothesis using PLS-SEM analysis and found that attitudes toward economic, social, and environment significantly affected support for sustainable tourism development. This study provides new insight into visitors' support of sustainable development and the factors affecting the variable.

ABSTRACTThe study aimed to investigate the specific soundscape dimension of visually impaired people and to learn about the possibly unique soundscape dimension elicited by the hearing sense alone. The soundscape dimension of the visually impaired will be used as a reference for improving urban parks to accommodate users inclusively. A semantic-scale questionnaire survey of sighted and visually impaired people in both in-situ and off-site modes was performed. Data were extracted using principal component analysis with polychoric correlations, which produced three soundscape dimensions elicited from the sighted and six from the visually impaired. In sum, evaluation of the park’s sonic environment identified the eventfulness soundscape dimension and the pleasantness soundscape dimension as being the most prominent for visually impaired and sighted people, respectively.HighlightsAn entirely aural soundscape method by visually impaired people is used to appraise urban parks.Soundscape dimension of eventfulness is the most prominent for visually impaired people.Visually impaired people extract more information from the acoustic environment.Visually impaired people sense the danger and direction of a space from sound.

Reaktor Serba Guna-G.A. Siwabessy (RSG-GAS reactor) is a pool type research reactor, located in Serpong village, Indonesia. For safety of RSG-GAS reactor, the maintenance level criterion of System, Structure and Component (SSC) can be carried out by assessing on occurrence likelihood of a potential risks due to ageing degradation and a Risk Priority Number (RPN) value for assigning maintenance criterion, respectively. The objective of present study is to propose using the Failure Mode and Effects Analysis (FMEA) for assigning the maintenance level criterion of SSC and implementing on JE01-AP01 primary pump within a RSG-GAS reactor. In this research paper, SSC screening and failure based maintenance methodology is identified and classified into suitable classes at radar diagram. Results show that SSC can be prioritized based on failure analysis so that maintenance level criterion for SSC can be determined. On the implemented study, preventive maintenance can be performed to JE01-AP01 primary pump because of its RPN value 270.

Reaktor Serba Guna-G.A. Siwabessy (RSG-GAS reactor) is a pool type research reactor, located in Serpong village, Indonesia. For safety of RSG-GAS reactor, the maintenance level criterion of System, Structure and Component (SSC) can be carried out by assessing on occurrence likelihood of a potential risks due to ageing degradation and a Risk Priority Number (RPN) value for assigning maintenance criterion, respectively. The objective of present study is to propose using the Failure Mode and Effects Analysis (FMEA) for assigning the maintenance level criterion of SSC and implementing on JE01-AP01 primary pump within a RSG-GAS reactor. In this research paper, SSC screening and failure based maintenance methodology is identified and classified into suitable classes at radar diagram. Results show that SSC can be prioritized based on failure analysis so that maintenance level criterion for SSC can be determined. On the implemented study, preventive maintenance can be performed to JE01-AP01 primary pump because of its RPN value 270.

Purpose: Research has been conducted to analyze the landslide in Banaran area, Ponorogo Regency. The landslides occurred on April 1, 2017. This study was conducted to know the subsurface conditions in the Banaran area to analyze the disaster mitigation efforts. The mitigation efforts are made to reduce the risk from landslides and possible landslides. Design/methodology/approach: The method used is the geo-electric resistivity method of Wenner–Schlumberger configuration. The research was conducted in three villages namely Banaran Village, Bekirang Village and Mendak Village. Findings: There are 12 resistivity measuring points with a track length of 410 m and a space of 10 m. The measured resistivity range is between 1.42 Ω.m and 67.500 Ω.m. The resistivity data and the local geological maps interpreted that the rocks in the Banaran area consist of clay, tuff lapilli, volcanic breccia and andesite lava. The landslide area begins at a depth of 8–35 m below the surface which is interpreted as tuff. Also, the thickness of the landslide material and the slope is = 400 which supports the occurrence of a more prominent landslide. The results of the parameter scoring of the landslide-prone areas indicated that the research area is very vulnerable to a landslide. The results of the interpretation indicate that the geo-electric resistivity method can provide a good overview for conducting landslide analysis, that is field slippage and potential material thickness occurrence landslide. Originality/value: This article is very specific as it attempts to discover how prone Banaran are is to landslide.

Co-production leadership is an emerging leadership model which is not a leader-centred. It involves leaders and followers working together to determine organisational outcomes. The followers' personal characteristics will determine the extent to which followers are involved in the leadership process. Followers also have a variety of beliefs about their role, both in the traditional perspective and within the framework of a partnership with leaders. This makes the co-production leadership model influences follower behaviours in the form of compliance and constructive resistance. This study aimed to develop a model of co-production leadership by examining the followers' characteristics as a predictor, and its impact on the follower behaviours, such as compliance and constructive resistance. This research was conducted on a political party, which has not been done in previous studies. To test the model developed in this study, partial least square (PLS) analysis was employed.

Post-traumatic central slip injuries complicated by boutonniere deformity continue to be Post-traumatic central slip injuries, resulting in boutonniere deformity, are a complex issue that can significantly impact hand function and quality of life. The deformity should be easily reduceable in the acute phase, but if left untreated, it shortens the oblique retinacular ligament, leading to chronic contracture. This is a challenging issue in hand surgery, as chronic central slip defects cannot be sutured like other tendon. Various methods for reconstructing central slips have been discussed, but the best method for subacute or chronic injuries remains unclear. This case presents a case of chronic traumatic boutonniere deformity with central slip defect reconstruction.

Trees and shrubs of the genus Cordiaare widely distributed in the warmer regions, including Indonesia. The aim of this study was to evaluate the analgesic and anti-inflammatory properties of the ethanolic extract of plant leaves in Wistar albino rats. The analgesic activity was evaluated using the hot plate method and acetic acid-induced writhing, and the anti-inflammatory activity was determined using carrageenan-induced paw oedema. The results showed that the Cordia sebestenaethanol extract (100, 200 and 400 mg/kg) exhibited significant analgesic effects in a dose-dependent manner in the two pain models tested. The extract also exhibited significant anti-inflammatory effects in the carrageenan-induced inflammation test. The data obtained support the traditional folklore therapeutic claim about its analgesic and anti-inflammatory properties. Nonetheless, further scientific investigation is required to establish its analgesic and anti-inflammatory properties in other experimental models and clinical settings.

Air pollution has become a growing concern, especially in urban cities with rapidly developing economies, increasing infrastructure and vehicular population, and reduced green spaces. Fossil fuel and transportation are the main source of pollutive particles (e.g., sulfur oxide and nitrous) released into the atmosphere. Once they have entered the atmosphere, these particles create health problems, degrade air quality, and cause acid rain. Seasonal investigations on rainwater chemistry and particulate matter pollution (SPM, PM10, and PM2.5) were conducted to understand the recent state of the ambient air quality in Jakarta, Indonesia. The characteristics of PM2.5were also analyzed during Ied Al Fitr in 2016 and 2017. Based on the observational data, the ambient air quality in Jakarta improved during the period of our study (2000–2016). The chemical constituents, i.e., the anion and cation concentrations, in precipitation show decreasing trends starting from 2006. Moreover, the PM10and SPM concentrations also decreased slightly. The causes of these favorable trends are climatic conditions—namely, an increasing trend of rainfall—and policy intervention. Additionally, an assessment during the feast of Ied Al Fitr in 2016 and 2017 indicated a further decrease in PM2.5due to highly reduced inner-city traffic. These events exhibited an extreme reduction of the PM2.5concentration in Jakarta.

To improve production efficiency and quality of fiber-glass boatyards many research have been done both through technological as well as management aspects. One of these developments is Vacuum Assisted Resin Transfer Molding (VARTM) which is claimed to have high strength and material efficiency. This method has not much been applied in Indonesian boatyards, most of them are still using conventional hand lay-up. The research is aimed to investigate the strength of the composite and the optimum amount of materials to obtain the required strength for its application on boat buildings. Experimental approach was conducted in the research using 800 biaxial and 900 unidirectional E-glass for reinforcement, and vinylester (RIPOXY R-802-EX-1) resin for the matrix. The ultimate tensile strength and Youngs modulus of the composites are obtained through tensile and flexural test based on ASTM D 3039 and ASTM D 790 standards. The data obtained are used to determine the optimum number of layers and fiber content on certain locations of the boat hull structure in order to comply with the requirements of classification rules.

This study discusses the results of experiments on flexural strength of the concrete beams using bambo strip notch as reinforcement, with variations in the distance between the notch at 40 mm and 50 mm. The flexural parameters assessed were the flexural moments and load-deflection behaviour. The number of concrete beams specimen was 9 units. One sets for 3 beams containing round steel 8 mm as reinforcement and two sets of 6 beams containing bamboo as reinforcement were tested for flexural strength under third point loading. All beam specimens size is 110x150x1700 mm. The data recorded while tested the flexure were a failure load, deflection and failure models. The failure loads of beams increased with increase in the number of notches bamboo strip in the tensile zone. The ultimate moment experimental and theoretical of bamboo strip notched concrete beams increased, with increase the number of notches bamboo strip in the tensile zone. Thus it can be concluded that inclusion of bamboo strip notches as reinforcement in tension zone improved the flexural capacity of concrete beams.

A lotus type-porous copper will be used to substitute wick materials from tabulate coral capillary for heat pipe applications. The lotus type-porous material are normally fabricated using Gasar process, in which unidirectional solidification was applied to the metal-eutectic systems to obtain long cylindrical pores in the direction of solidification. A new process is proposed to fabricate the lotus type-porous material using slip casting and sintering. As an initial work, this paper is aimed to obtain appropriate processing parameters of fabrication of lotus-type porous copper using slip casting and sintering techniques. Nylon strings were used as pore formers to form cylindrical pores. They were coated with copper slurry consisting of copper powder and binding agent. The coated nylon strings were arranged in a mold and the slurry were poured. After drying, these castings were sintered at various sintering temperatures and sintering times. The results showed that starch as the binding agent is superior to PVA. The mixture of starch-water with starch content of 97%, the copper slurry with copper content of 50% by volume, the copper powder size of 200 µm, the sintering temperatur of 900°C, and the sintering time of 60 minutes are able to produce lotus-type porous copper similar to that produced through Gasar process.

Medical malpractice and prostate cancer screening are important issues in the current landscape of health care. We identified factors contributing to litigation in the diagnosis of prostate cancer.

Management Accountants (“MA”) are strategic partners in provideing information for decision-making, but they have a problem on how to mastering IFRS (International Financial Reporting Standard) based on the G20 agreement. In this research, there are three main objectives to be achieved, first, Review the knowledge of IFRS in Indonesian MA, then, second, compare it with the Malaysian MA, and, third, learn the application of IFRS in the Malaysian. The research method is a qualitative. The results of the research in sample data will show that the knowledge of IFRS for Indonesian MA still has a minority when compared to Malaysian.

Background Schwannomas of the anterior skull base (ASB) and sinonasal tract are extremely rare. These lesions mimic other pathologies such as olfactory groove meningiomas, hemangiopericytomas, and esthesioneuroblastomas. Because of their low incidence, ASB and sinonasal tract schwannomas have not been well characterized. A systematic review of ASB and sinonasal tract schwannomas was conducted to further elucidate the presentation and surgical management of these lesions.Methods A MEDLINE/PubMed search was performed, identifying 71 articles representing 94 cases of ASB and sinonasal schwannomas. Each case was analyzed for demographics, clinical presentation, anatomic location, radiographic features, and surgical treatment.Results In 94 patients with ASB and sinonasal schwannomas, 44 (46.8%) were exclusively sinonasal, 30 cases (31.9%) were exclusively intracranial, 12 (12.8%) were primarily intracranial with extension into the paranasal sinuses, and 8 (8.5%) were primarily sinonasal with intracranial extension. Headaches and nasal obstruction were the most common presenting symptoms occurring in 30.9 and 29.8% of cases, respectively. Magnetic resonance imaging typically showed a hyperintense mass on T2-weighted imaging (70%) and hypointense (41%) on T1-weighted imaging. Most patients underwent surgical gross total resection via craniotomy, endoscopic endonasal approach, rhinotomy, or other sinonasal approaches. Recurrence occurred in three cases ranging from 4 months to 13 years. Postoperative complications included cerebral spinal fluid leakage, bacterial meningitis, epidural hematoma, and pneumocranium.Conclusion ASB and sinonasal schwannomas are rare lesions and should be considered in the differential diagnosis of ASB masses involving the cribriform plate with sinonasal extension. Gross total resection of these lesions should be considered the goal of operative management.

Racial differences exist in the incidence of prostate cancer (PCa). Although many studies have looked at the performance of prostate-specific antigen (PSA) and PSA density (PSAD) in the detection of PCa, only a few have looked at it in relation to Indonesian men. The objective of this study is to find out better PSA and PSAD cutoff point in the detection of PCa in Indonesian men.

In recent years, many infrastructures have been deteriorating. In order to maintain sustainability of those infrastructures which have significant influence on social lifelines, economical and rational maintenance management should be carried out to evaluate the life cycle cost (LCC). The development of structural health monitoring systems, such as deriving evaluation techniques for the field structural condition of existing structures and identification techniques for the significant engineering properties of new structures, can be considered as the first step in resolving the above problem. New innovative evaluation methods need to be devised to identify the deterioration of infrastructures, e.g. steel tendons, cables in cable-stayed bridges and strands embedded in pre- or post-tensioned concrete structures. One of the possible solutions that show ‘AtoE’ characteristics, i.e., (a)ccuracy, (b)enefit, (c)ompendiousness, (d)urability and (e)ase of operation, elasto-magnetic (EM) actual stress sensory technology utilizing the sensitivity of incremental magnetic permeability to stress change, has been developed. Numerous verification tests on various steel materials have been conducted. By comparing with load cell, strain gage and other sensory technology measurement results, the actual stresses of steel tendons in a pre-stressed concrete structure at the following stages have been thoroughly investigated: (i) pre-stress change due to set-loss (anchorage slippage) at the tendon fixation stage; (ii) pre-stress change due to the tendon relaxation stage; (iii) concrete creep and shrinkage at the long term pre-stressing stage; (iv) pre-stress change in the cyclic fatigue loading stage; and (v) pre-stress change due to the re-pre-stress setting stage. As the result of this testing, it is confirmed that EM sensory technology enables one to measure actual stress in steel wire, strands and steel bars precisely without destroying the polyethylene covering sheath and enables one to provide adequate accuracy and reliability for monitoring actual stresses of those steel tendons during the life cycle of infrastructures. An example of a field application at a cable-stayed bridge is described.

KNOTTED1-like homeobox (KNOX) genes serve important roles in meristem function and many developmental processes in all higher plants. In Arabidopsis, studies of KNOXgenes especially among members of class II KNOXgenes remain limited and functional data are largely lacking. In the present study, we established a reproducible protocol that is important for genetic studies of KNOXgenes using Arabidopsisinsertional mutants. This protocol contains a reproducible and serial procedure containing detailed and step-by-step laboratory and field works covering all experiment steps from the screening of homozygous mutant lines to the KNOXexpression analysis using qRT-PCR in a single paper. The troubleshooting and challenges that might occur are also presented and discussed. T-DNA insertion mutants for all Arabidopsis KNOXgenes (except for knat4) were isolated based on kanamycin screening, phenotype selection, and PCR genotyping. Surprisingly, the insertions resulted in strong repression of the respective KNOXgenes. However, no gene suppression was observed for the positively selected knat5mutant. Moreover, qRT-PCR was effective for transcript analysis among the knoxmutant samples. The use of different relative expression quantification produces a similar indication of expression level. Overall, the proposed procedure is highly effective for expression studies of KNOXgenes in Arabidopsismutants and will serve as a fundamental work protocol to open opportunities for genetic studies of genes involving insertional mutants in Arabidopsis.

“Neonatal hepatitis” may result from a variety of metabolic and toxic causes as well as infection. Recent interest has evolved from study of the neonatal-hepatitis-biliary atresia symptom complex. New information about the development of hepatic function has provided insights into the mechanisms of biliary lipid secretion, the regulation of protein synthesis, and the processing and excretion of whole proteins or exogenously derived antigens in the bile.

Summary In a boy with a defect in fatty acid oxidation due to the hepatic form of carnitine palmitoyltransferase-1 deficiency, plasma carnitine concentrations were found to be twice normal. The elevation in plasma carnitine levels was accompanied by an unusually high renal threshold for free carnitine, suggesting a secondary increase in carnitine transport. Similar to other fatty acid oxidation disorders involving the carnitine cycle, urinary dicarboxylic acids were not abnormally elevated during illnesses. The combination of elevated plasma carnitine levels and absence of dicarboxylic aciduria may help to distinguish the hepatic form of carnitine palmitoyltransferase-1 deficiency from other defects in fatty acid oxidation.

In a boy with a defect in fatty acid oxidation due to the hepatic form of carnitine palmitoyltransferase-1 deficiency, plasma carnitine concentrations were found to be twice normal. The elevation in plasma carnitine levels was accompanied by an unusually high renal threshold for free carnitine, suggesting a secondary increase in carnitine transport. Similar to other fatty acid oxidation disorders involving the carnitine cycle, urinary dicarboxylic acids were not abnormally elevated during illnesses. The combination of elevated plasma carnitine levels and absence of dicarboxylic aciduria may help to distinguish the hepatic form of carnitine palmitoyltransferase-1 deficiency from other defects in fatty acid oxidation.

Flash points of organic molecules play an important role in preventing flammability hazards and large databases of measured values exist, although millions of compounds remain unmeasured. To rapidly extend existing data to new compounds many researchers have used quantitative structure‐property relationship (QSPR) analysis to effectively predict flash points. In recent years graph‐based deep learning (GBDL) has emerged as a powerful alternative method to traditional QSPR. In this paper, GBDL models were implemented in predicting flash point for the first time. We assessed the performance of two GBDL models, message‐passing neural network (MPNN) and graph convolutional neural network (GCNN), by comparing against 12 previous QSPR studies using more traditional methods. Our result shows that MPNN both outperforms GCNN and yields slightly worse but comparable performance with previous QSPR studies. The average R2and Mean Absolute Error (MAE) scores of MPNN are, respectively, 2.3 % lower and 2.0 K higher than previous comparable studies. To further explore GBDL models, we collected the largest flash point dataset to date, which contains 10575 unique molecules. The optimized MPNN gives a test data R2of 0.803 and MAE of 17.8 K on the complete dataset. We also extracted 5 datasets from our integrated dataset based on molecular types (acids, organometallics, organogermaniums, organosilicons, and organotins) and explore the quality of the model in these classes.

Batang Kuranji is one of the biggest river in Padang City with catchment area of 202,7 km2. In the middle segment of this river have degraded significantly, especially in the downstream side of Gunung Nago Dam after the big flash flood in 2012. This also supported by the steep river slope of 0.017 and the activity of excavation of sand and gravel downstream of Gunung Nago Dam. Based on this, the authors are interested in examining the study of riverbed change and bed-load transport in the middle segment of the Batang Kuranji River, to determine the amount of sediment and changes in riverbed elevations that occur and analyse the location of proper building to reduce water damage. In conducting this research, researchers collected primary data, namely direct sampling in the field and secondary data from various relevant literature sources. In this study seven methods of calculating bed-load transport were used, including Meyer Peter Muller, Einstein, Einstein-Brown, Kalinske, Frijlink, Engelund and Hansens, and Van Rijn. Based on the results, there was a change in riverbed elevation, in the period of 2011 to 2013 there was a scour volume of 902,527 m3 greater than the sediment volume of 193,435 m3 where the sediment occurred was only 21.43% with the deepest scour 10.52 m. Kalinske sediment transport method has the closest value to manual calculation. The comparison between Kalinske method and manual calculation respectively; 0.056 m3/day and 0.187 m3/day in S12 sample; 0.312 m3/day and 0.554 m3/day in S23 sample; and 0.020 m3/day and 0.081 m3/day in S33.

The purpose of this study is to explore the role of e-commerce that is expected to provide significant benefits in the business world. Companies that are able to properly implement e-commerce can grow the number of profits, increasing customer numbers, in addition to giving a positive impact on the development of e-commerce business is not profitable. The method used was a descriptive method with a qualitative approach. This method was used to describe the phenomenon of business actor activity in utilizing e-commerce to increase the sales force of the business. With the utilization and use of internet technology, the role of e-commerce is expected to provide great benefits for the company. The result of this research shows that companies that are able to utilize e-commerce can improve competitiveness and sales.

XYZ is a distributor of various consumer goods products. The company plans its delivery routes daily and in order to obtain route construction in a short amount of time, it simplifies the process by assigning drivers based on geographic regions. This approach results in inefficient use of vehicles leading to imbalance workloads. In this paper, we propose a combined method involving heuristic and optimization to obtain better solutions in acceptable computation time. The heuristic is based on a time-oriented, nearest neighbor (TONN) to form clusters if the number of locations is higher than a certain value. The optimization part uses a mathematical modeling formulation based on vehicle routing problem that considers heterogeneous vehicles, time windows, and fixed costs (HVRPTWF) and is used to solve routing problem in clusters. A case study using data from one month of the company's operations is analyzed, and data from one day of operations are detailed in this paper. The analysis shows that the proposed method results in 24% cost savings on that month, but it can be as high as 54% in a day.