An integrated shipment planning and storage capacity decision under uncertainty

Currently, refined petroleum products are manufactured by six refineries in South Africa. The supply of refined petroleum products is supplemented by imports of refined petroleum products. These refined petroleum products are transported by pipeline, rail, road, sea and a combination thereof to depots across the country. These products are then distributed directly to commercial customers through points of resale in the form of retail service stations. The challenge is that the storage facilities and distribution networks in South Africa are currently utilised to its full capacity. There is a need to expand current storage infrastructure or to erect new storage facilities to facilitate imports. Durban Port that currently handles 70% of the country’s crude oil and 40% of refined products is also utilised to its full capacity. The investigated problem pertains to the limited storage and transport capacity available for the distribution of petroleum products in the country. The interview protocol, which was based on the literature reviewed, was used for compiling the primary data for the case study. Selected findings revealed that the respondents perceived that storage capacity is the most significant constraint militating against adequate supply by the supply chain. The findings also indicated that the respondents were of the opinion that transport rates and routes (cost of logistics) are the greatest contributor to the prices of products. As a result, there appears to be a major scope for improvement in terms of the usage of pipelines and rails for the movement of petroleum products.Keywords: Petroleum products, storage facilities, supply chain, transportation, South African energy sector.Disciplines: civil engineering, architecture, business studies, energy studies

Multiple-method analysis of logistics costs

One of unique characteristics of Thai jasmine rice is its aroma, which can easily reduce in various conditions during post-harvesting activities, especially in rice milling stage. This study aims to investigate logistics cost analysis of the rice mill of Kasetwisai Agricultural Cooperative, Ltd. by using activity based costing (ABC) method and to define key activities for the improvement of the rice aroma loss reduction. The results show that the activity that has the highest logistics cost is warehousing at 26.52%, followed by material handling at 24.27%, transportation at 12.33% and packaging at 10.84% of the total logistics cost, respectively. The total logistics cost per unit of the rice mill is about 4.52 baht/kg. Findings from an in-depth interview revealed that warehousing and transportation can be major activities influencing aroma loss in jasmine rice. To reduce the aroma loss in a cost effective way, the Kasetwisai Agricultural Cooperative, Ltd. should focus on storage time and temperature in warehousing and transportation systems. In addition, the collaboration of the rice miller with supply chain partners should be encouraged to cut the logistics cost and to improve the quality of rice. Keywords: Activity Based Costing; Aromatic Rice; Jasmine Rice; Logistics Cost; Value Chain

The rapid increase in global warming due to greenhouse gas emission, accompanying the development of human civilization, has led to the establishment of the global common goal of achieving called Net-zero, by 2050. To reach this goal, several efforts are being made through the expansion of renewable energy and methods such as CCS (Carbon Capture and Storage). This study describes a simulation study aimed at improving the efficiency of CO2 storage using the CO2-EWR (Enhanced Water Recovery) technology, as well as an evaluation of its feasibility in the field, through indirect comparative analysis with pilot data.The CO2-EWR technology takes advantage of the concept that the pressure in the aquifer decreases due to the extraction of produced water, allowing for additional CO2 injection into the aquifer due to the reduced pressure. In the field experiment, a steel pipe with a diameter of 0.2 m and a length of 5 m was filled with glass beads (70-110 µm) to simulate aquifer conditions. In the experiments, absolute permeability was measured, and 85 Bar of supercritical CO2 was injected into the pipe, simulating aquifer conditions of 35°C and 80 Bar. And supercritical CO2 flow rate at the breakthrough point at the back end of the pipe was measured. The absolute permeability, measured using Darcy’s law, was found to be approximately 6548 mD and CO2 flow rate at the breakthrough point was 5.46 kg. The simulation modeling conditions involved filling a pipe of the same size with small size glass beads (40-70 µm) and injecting 40°C, 84 Bar supercritical CO2 into a simulated environment of 40°C and 80 Bar, with a breakthrough point of supercritical CO2 flow rate measured at 3.69 kg. Although a direct comparison between the field data and the modeling conditions is difficult due to differences in conditions, the higher permeability and injection pressure in the field data suggest meaningful results. Near future, direct comparisons of modeling results under identical conditions as the field site, along with additional CO2-EWR tests, simulating various conditions, are expected to provide reasonable data. This data will contribute to optimizing the CO2 injection efficiency and storage capacity, offering a guideline for field application. AcknowledgementThis work was supported by Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government (MOTIE) (20212010200010, Technical development of enhancing CO2 injection efficiency and increase in storage capacity)

This research tries to shed light on precise values of logistics costs that so far undisclosed. The values are important for every project planners to evaluate, control and monitoring, and especially imperative for procurement activities. Tender, bidding, and defining the scope of contracts and value can be well organized without time-consuming. This research uses methodology previously developed by Subiyanto (2020a) and discussed only a few particular and directly related to the logistics. The model had been decomposed by utilizing path analysis and the data had been regressed to define variables as the most inflator for logistics. The findings are total logistics costs in Indonesia generally at around 14.6% to total costs of investment. It consists following of insurance cost 0.11%, costs for customs clearance 6.52%, foreign logistics costs 6.62%, domestic manufacture 0.47%, and domestic logistics costs 0.89%. This research is not discussing logistics costs relating to human resources, human travelling, and internal logistics conducted by vendors or contractors as the scope included counted within their procurement contract. These results are important as guidance for project planners, controllers, and other parties to prepare costs more precisely. Negotiating to the banks will be easier as the more precise amount of budgets had been estimated. Due to the important values that have been identified, there will help transparency and governance conducting the projects. Procurement processes involving societies are more objective and better. This is a novelty finding as previous researchers have not decided yet.

Storage capacity of carbon dioxide hydrates in the presence of sodium dodecyl sulfate (SDS) and tetrahydrofuran (THF)

Metal organic frameworks (MOFs) are widely studied because of their unique structures and wide applications represented by gas separation, gas sensor and electrocatalysis. In our previous research, 4 types of Zn-telephthalic acid (TPA) MOFs were synthesized via microwave hydrothermal reaction by varying pH of precursor solution. One of the Zn-TPA MOFs in a Zn4(OH)6(C8H6O4) composition exhibited a stable reversible redox reaction accompanied with proton exchange owing to its structural rigidity brought by para positional carboxyl groups (–COOH), to show its usefulness as a negative electrode material for redox batteries. In this study, we have employed trimellitic acid (1,2,4-benzenetricarboxylic acid, abbreviated as TMLA) for synthesis of Zn-based MOFs. TMLA has an extra carboxyl groups to the structure of TPA, so that an increased storage capacity is anticipated. Aqueous solutions containing 0.1 M Zn (CH3COO) 2 and 0.035 M TMLA with pH adjusted between 7 and 5 by KOH were put into a Teflon-lined vessels for microwave (2.45 GHz) reaction at 150℃ for 30 min. The powder samples were centrifugally collected, washed and dried for analysis by XRD and TG-DTA. Paste containing 35wt% powder was coated F-doped tin oxide (FTO) glass to fabricate mesoporous electrodes with ca. 10 μm thickness for their evaluation by cyclic voltammetry and chronoamperometry in a 0.1 M KCl. Three types of Zn-TMLA MOFs were synthesized depending on pH and two of them in layered structures with 14.4 and 12.2 Å spacing could be isolated, with their compositions determined as Zn5(OH)7(C9H3O6) and Zn4(OH)5(C9H3O6)•1.5H2O from TG-DTA, named as types A and B, respectively. Both A and B exhibit reversible redox reactions as shown in Fig. 1, with their coulombic reversibility of 85 and 90%, E 1/2 values of -1.12 and -1.10 V vs. Ag/AgCl, respectively (determined from 70 mV s-1 scans), similar to 90% and -1.03 V found for Zn-TPA MOF. Oxidation peaks are positively shifted on the slow end of the potential scanning, unlike the case with Zn-TPA, which might be associated with reconstruction of the MOF structure, upon proton exchange in the redox reactions expressed as follows, Zn5(OH)7(C9H3O6) + 3H+ + 3e- ⇄ Zn5(OH)7(C9H6O6) (A) Zn4(OH)5(C9H3O6) + 3H+ + 3e- ⇄ Zn4(OH)5(C9H6O6) (B) The presence of an extra carboxylate in TMLA could be the reason of the structural flexibility to cause the observed change. An important difference is noticed for kinetic behavior between A and B. While A shows slow reduction and relatively fast oxidation, similar to that found for Zn-TPA MOF, those of B are highly reversible, indicating facile exchange of protons, possibly owing to the presence of hydration water in its structure. Potentiostatic full charging an discharging of the electrodes revealed redox active fractions of 31 and 22% of the total amount of A and B deposited on FTO according to the reactions expressed by Eqs. (A) and (B) above, respectively, being somewhat smaller than the value found for Zn-TPA (35%). However, when the absolute storage capacity per molar amount of Zn is compared, similar values of 1.79 × 104, 1.59 × 104, and 1.69 × 104 C mol-1 are found for A, B and Zn-TPA, respectively. Thus, upon improvements of redox active fractions by optimizing the film preparation procedure as well as the thickness, higher storage capacity is expected for Zn-TMLA MOFs than Zn-TPA, because of the contribution of the third carboxylic acid group. Figure 1

The methane hydrate formation rate and storage capacity seriously restrict hydrate storage and transportation technology development. In this study, the methane hydrate formation process in a 0.30 wt % sodium dodecyl sulfate (SDS) and mixed systems of 0.30 wt % SDS with saturated sodium sulfate (Na2SO4) was investigated. The effects of SDS concentration and initial pressure in the mixed systems on the methane hydrate formation rate and amount were studied. It was found that the methane hydrate formation process can be divided into four stages: the first rapid formation stage, the nucleation aggregation stage, the second rapid formation stage, and the hydrate stable stage. The precipitated Na2SO4 crystals provided seeds for methane hydrate formation, which can improve the hydrate formation rate and storage capacity. The Na2SO4 crystals mainly affect the first rapid formation stage and the nucleation aggregation stage. The methane hydrate formation rate in the first stage under the synergistic effect of 0.30 wt % SDS+Na2SO4 is 1.2 times higher than that of SDS alone. When increasing the formation pressure from 6 to 10 MPa, the hydrate formation rate under the synergistic effect of 0.30 wt % SDS+Na2SO4 in the first stage increased by 8 times. In the SDS+saturated Na2SO4 system, the methane hydrate formation rate and storage capacity increase with the increase of SDS concentration. SDS concentration mainly affects the first rapid formation stage. This paper is helpful to propose a new method for the methane hydrate rapid formation and is crucial for the development of hydrate storage and transportation technology.

PT. OPQ is a company engaged in the automotive manufacturing industry. The company produces bolts for the safety area, it is related to the lower body of the four-wheeled vehicle. PT. OPQ was established in 2014 and today has already been the supplier for several major automotive companies in Indonesia. The demand of PT OPQ that must be fulfilled is increasing as the amount of consumer is increasing too. Due to the high demand, so the raw material stockout occurs. This make the company's service level is below the standard. This study involved 48 sku of material raw materials that have normal distributed demand. Inventory policy applied in this research is periodic review (R, s, S) with the aim to minimize total cost of inventory and improve service level of company. The result of this research was found to decrease total inventory cost by 15% with the value of existing inventory cost Rp1.100.879.479,- to Rp 936.061.349,- . In addition, service level at PT. OPQ has increased with the value of existing conditions 85% to 99%.

Domestic product oil sales companies are striving for decreasing logistics cost and improving logistics service level to strengthen core competitiveness. The paper will explore how to optimize the secondary distribution of oil product, with respecting to the relationship between logistics cost and logistics service level. Firstly, the character of product oil logistics and the relationship of benefit deviation between logistics cost and logistics service is elaborated. Secondly, the optimization model of product oil secondary distribution based on particular service level is built. At last an example is introduced to verify the effectiveness of this model. The result provides some support on decision making to the domestic product oil sales companies.

Traditionally, any capacity planning problem is modeled with deterministic workloads by considering the peak workload for resource allocation. In the context of businesses using cloud service, cloud provider could allocate resources for peak workload which could lead to under utilization of resource and charging users for unused yet provisioned resources. Hence we came up with a better capacity planning algorithm which could ensure that we plan for peak usage but do not provision for it.In our approach, we modeled the problem as a stochastic optimization problem with the objective of minimizing the number of servers considering two important constraints a) stochastic nature of workloads and b) minimizing the application SLA violations. We implemented the model using genetic algorithm and to address the stochastic nature of work loads, we reserved a free pool of resources in each server by the quantity determined by our algorithm. We evaluated the solution with real sever utilization data from a datacenter seeking consolidation. We did comparative analysis on the number of servers required suggested by our solution vs. peak work loads based solutions for various service levels. Our results illustrate that reserving certain amount of resources in servers for addressing variability of workloads gives better results in terms of lesser number of servers compared to packing resources based on peak workloads for the same service levels.

The Facility layout of flexible manufacturing workshop is designed under process principle, which is suitable for medium and small batch production．However, large WIP is produced under this facility layout model, and the material transport is relatively disorderly, the production cost is caused very high. Aiming on the problem, the facility layout with variety of materials is researched, and the mathematical model of lowest logistics cost is established with the total logistics cost as the objective function. Finally, according to the workshop equipment layout optimization process, the simulation mode in unit is established with the computer simulation software eM-Plant, and the logistics cost is optimized and compared with the initial result.

Storage capacity plan and transition of heterogeneous energy at regional strategic level: A financial derivative perspective

The current work shows the application of reverse logistics in the supply chain of a multinational company wich distributes mass consumption products focused on re-utilization of packaging boxes, and increase of storage capacity and product transportation. Based on the methodologies developed, there is a model developed in multinational company of consumer products dentered on the OTB, PMBOK and Lean Six Sigma methodologies. This model has been successfully implemented in: Brazil, Mexico, Argentina and Colombia. The execution includes the following stages: identifying which products or stock keeping units in the warehouse can be standardized, designing packaging prototypes of packages or boxes that can be reused from the manufacturers of raw materials until the finished product and that can be used for reuse in packaging of other similar products, quality tests are executed in order to ensure the strength and longevity of the boxes. As a result of its implementation, an increase of financial efficiency was obtained for the company in case, , reducing its logistics costs in comparison with the sales revenues by around 8%, as well as a significant improving of its environmental management.

Objective To assess the impact of two different automated dispensing machines (‘robots’) on safety, efficiency and staff satisfaction, in a UK hospital setting. Setting An NHS teaching hospital trust with two main sites each comprising 450 beds. A Swisslog Pack Picker automated dispensing machine was installed in the dispensary at site 1 in December 2003, and a Rowa Speedcase at site 2 in October 2005. Method A before-and-after study design was used on each site, with site 2 acting as a control for site 1. Staff recorded data on dispensing errors identified at the final-check stage; an observer recorded the time taken to label, pick and assemble dispensed items; we recorded turnaround times for the different types of prescription and assessed storage space efficiency. We also used questionnaires to explore staff views. Key findings The robot resulted in a significant decrease in dispensing errors on each site (from 2.7 to 1.0% of dispensed items on site 1, and from 1.2 to 0.6% on site 2). Reductions occurred in errors involving wrong content; there was no clear effect on labelling errors. There were reductions in the time required to pick items for dispensing; there was no impact on labelling or assembly times. There was no conclusive effect on turnaround times. Increases in storage capacity occurred on each site; staff on site 2 were more satisfied following introduction of the robot; there was no difference on site 1. Conclusion Installation of a dispensary robot has modest benefits in terms of reduced dispensing errors, reduced picking times, increased staff satisfaction and increased storage capacity; there was no conclusive impact on turnaround times. These findings seem to be independent of the type of robot installed.