Total Inventory Research Articles

Unexpected Dioxin Formation During Digestion of Soil with Oxidizing Acids.

Dioxins, such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), are among the most toxic unintentionally produced persistent organic pollutants, and their emission is of great concern. Herein, we discovered abundant dioxin formation in soil and various organic carbon-containing matrices after digestion with aqua regia. Σ17PCDD/Fs concentrations were in the range of 66.6-142,834 pg/g dw (5.6-17,021 pg WHO2005-TEQ/g dw) in 19 soil samples after digestion with aqua regia for 6 h. Σ17PCDD/Fs concentration was significantly and positively correlated with soil organic carbon content (R2 = 0.89; p < 0.01). Compared with cellulose and lignin, humic acid served as an important organic matter component that was converted to PCDD/Fs during soil digestion. Strong oxidation and production of reactive chlorine by aqua regia may be the key factors in the formation of PCDD/Fs. The yearly emission of PCDD/Fs due to digestion with strong acids by the inspection and testing industry was estimated to be 83.8 g TEQ in China in 2021 based on the highest level, which was ∼0.9% of the total dioxin inventory in China. Great attention should be paid to unexpected dioxin formation during digestion processes considering the potential risk of release from laboratories and enterprises.

Indicators of the biological cycle of 90Sr in birch forests of the Bryansk region 30 years aft er the Chernobyl fallout

In the paper, the features of the biological cycle of 90Sr in the birch forests of the Bryansk region in the remote period aft er the Chernobyl fallout are discussed. Specific activity and inventories of 90Sr in soil, diff erent structures and types of tree and herbaceous-shrubby stories, higher fungi, and litter are given. It is shown that at present the major part of 90Sr in the contaminated birch forests of the Bryansk Polesie is accumulated in the soil (82,3%), of which about 71% is in the mineral soil horizons. The biota contains only 17,7% of the total radionuclide inventory with maximum values in the tree story. Th e contribution of herbaceous-shrubby vegetation and higher fungi is small, &lt;0,5%. In birch forests 3,07 kBq·m-2 90Sr is involved in the biological cycle, which is about 3% of its total stock in the ecosystem and approximately corresponds to the radioactive decay of this radionuclide. The main part of the 90Sr goes for formation of annual growth of the stand, while the contribution of higher fungi to the cycle exceeds the contribution of the herbaceous-shrubby layer. Th e 90Sr return to soil is lower (48,2%) than its fi xation in annual biomass growth (51,8%).

Inventory Management Analysis at UD Nuada Truss Tabanan Branch

Inventory management must be considered by the company so that the inventory costs incurred do not burden the company too high and anticipate the occurrence of inventory shortages. This research was conducted at UD Nuada Truss Tabanan branch with the aim of knowing whether the performance of inventory management is optimal or not. This study uses descriptive analysis techniques using quantitative and qualitative data obtained from observations and interviews. This descriptive analysis technique will be explained in stages starting with ABC analysis, calculating EOQ, safety stock, reorder point, maximum inventory, inventory turnover, and total inventory cost. The results showed that the inventory management implemented by UD Nuada Truss Tabanan branch was not optimal. This is shown by the comparison of the total inventory cost incurred by the company's inventory management which is higher than the inventory management using the EOQ method. the total inventory cost incurred by the company's inventory management was IDR 69,074,629, while the inventory management using the EOQ method was IDR 53,038,890. The application of inventory management using the EOQ method provides efficiency to the company in the amount of IDR 16,035,739 (23.22%).

Application of the Economic Order Quantity (EOQ) Method in Soybean Raw Material Inventory Control at the Haji Maman Tofu Factory in Matraman District, East Jakarta

This research is based on the lack of implementation of a method in controlling the inventory of soybean raw materials at Haji Maman’s Tofu Factory in the Matraman District of East Jakarta. Haji Maman’s Tofu Factory stil relies on daily records and sometimes uses estimates or assumption in its operational activities. In the procurement of raw materials, there is often an excess due to the lack of precise calculations regarding the ordering needs of raw materials, resulting in accumulation in the warehouse. In this study, the researcher utilized the Economic Order Quantity (EOQ) method, which determines the optimal quantity of raw material orders for each purchase, the optimal purchase frequency, and establishes the Re-Order Point. The approach and type of research used is a quantitative research method with a descriptive research approach. The objective of this study is to examine the implementation of the EOQ method in controlling the inventory of soybean raw materials at Haji Maman’s Tofu Factory in the Matraman District of East Jakarta. Data Collection was conducted through observation and interviews with Mr. Haji Maman, the owner. The data analysis technique employed was the EOQ method, taking into account purchase frequency, Re-Order Point, and Total Inventory Cost (TIC). The results of this study indicate that the optimal average frequency of raw material orders is 17 times per year. The total inventory cont using Haji Maman’s Tofu Factory policy amounts to Rp. 9,709,261, while using the EOQ method it amounts to Rp. 7,492,129, resulting in savings of Rp. 2,217,132 for Haji Maman’s Tofu Factory. The Re-Order Point is determined to be 216 kilograms.

Analysis Of Spare Parts Inventory Planning And Control To Improve Cost Efficiency At Pt Manunggal Jaya Makmur

PT Manunggal Jaya Makmur is one of the companies engaged in the transportation and contracting-based sector that provides integrated services from the start point to the end. In addition, it is also engaged in the repair of heavy equipment such as mixer trucks, dump trucks, colt diesel, and repair of other heavy equipment. In supporting the company's activities, PT. Manunggal Jaya Makmur implements a strategy for supplying raw materials and spare parts. In its operational activities, PT. Manunggal Jaya Makmur is still constrained by the overstock problem which ultimately causes a buildup of goods. In this study, material classification was carried out using ABC Theory analysis. Then the methods used in planning and controlling inventory management are the POQ and EOQ methods. After getting the results, the methods used during the research will be compared with the methods that have been applied so far in the company to find out the most effective methods to be applied in cost efficiency and work productivity and can maximize the profits received by the company. Based on the analysis carried out, the cost of calculating the total inventory of spare parts using the EOQ method was Rp. 205,513,000, the LFL method was Rp. 274,141,349 and the POQ method was Rp. 273,502,120. So, from these data, it can be concluded that the most optimal total cost of inventory is the EOQ method to produce greater profits and minimize overstock.

210Pb Deposition Distribution in the Northern Hemisphere Based on a Long-Range Atmospheric Transport and Deposition Model Calculation

This study delves into the long-term atmospheric transport and deposition of 210Pb in the Northern Hemisphere by using the atmospheric transport model HIRAT. The calculation for the four-year (2012–2015) period showed an average deposition flux of 13.0 Bq m−2 month−1 with significant seasonal variations characterized by higher deposition rates during summer and lower during winter. High deposition was found in the Northern Bay of Bengal and Bangladesh regions, Southern China, the Western Philippine Sea, the Eastern Japan Sea, the Northwestern Pacific region, the Eastern and Western coasts of North America, the Caribbean Sea, the Eastern Pacific region off of Central America, the Central Atlantic region between Central America and Africa, and the Northwestern Atlantic Ocean. Deposition patterns varied across latitudinal zones, with tropical areas experiencing the highest deposition and polar/subpolar zones the lowest. This study emphasized the impact of monsoons on the significantly large 210Pb deposition in the Japan Sea region. Furthermore, this study showed that the lower troposphere (0 to 3 km) dominates with about 53%, and the middle troposphere (3 to 6 km) and upper troposphere (above 6 km) also contribute significantly to the total 210Pb inventory with 37% and 10%, respectively. These findings provide essential insights into the characteristics of atmospheric transport and deposition of 210Pb, and their mechanisms.

Aplikasi Metode EOQ Dalam Efisiensi Total Biaya Persediaan dan Optimasi Pengendalian Persediaan Bahan Baku Thinner di PT. XYZ

Raw material procurement policies play an important role in the production activities of a company. In order to maintain customer trust, PT. XYZ is very concerned about the quality and timeliness of the products it produces. This research was conducted to analyze raw material procurement policies and apply the Economic Order Quantity (EOQ) method which is considered effective as a measure to optimize inventory control efforts and minimize total inventory costs. This study shows that the total inventory cost (TIC) using EOQ has a more economical amount of Rp. 150,080, compared to the TIC resulting from company policy, namely Rp. 967,671. The EOQ model also takes into account the economical purchasing process which is carried out 5 times a year with a purchase quantity of 239 units per order, reorders are made when the remaining stock is 44 units and safety stock is 32 units. In order to maximize the inventory function, the maximum stock or limit on the availability of stock in the warehouse is also taken into account, which is 277 units.

Optimal inventory policies for finite horizon deterministic inventory models for non-instantaneous deteriorating items and permissible-delay in payment

This paper is concerned with the search for the optimal inventory policy for a finite horizon inventory model with time-varying demand, non-instantaneous deteriorating items, and permissible delay in payment. The optimal inventory policy consists of the determination of the number and timing of replenishment schedules that minimise some total inventory costs. The search for such policy is formulated as a mixed integer nonlinear programming problem (MINLP). It turns out that the non-instantaneous deterioration phenomenon coupled with permissible delay in payment introduce non-smoothness in the objective function of the MINLP. This leads to failure of direct applications of known solution methods to the MINLP. To circumvent this problem, a methodology is proposed for solving fully the MINLP problem. It is shown, through careful mathematical analysis, that earlier results on similar problems can be adapted to solve this problem. Conditions under which the solution of the MINLP is unique are identified. Moreover, convexity with respect to the number of replenishment orders is established. This makes the search for the optimal inventory policy handy. Numerical experiments are also conducted to test the applicability, to identify the key elements and to provide managerial insights to the model.

Development of Inventory Model to Reduce Total Inventory Costs at RSUD Mentawai

The inventory policy problem is a problem in the inventory system related to how to ensure that each usage demand can be met at minimal cost. In the healthcare industry, it is imperative that the procurement and use of stock is not only cost-effective, but also that the required stock is always available. Discrepancies between total inventory and usage can lead to damage to BMHP inventory as the items have expiry dates, as well as excess total inventory costs. The problem of total inventory costs exceeding the budget occurs because overstock is 83% of the total need, overstock is caused by an excessive number of drug orders purchased. The purpose of this study is to reduce the total cost of inventory by considering expiry costs, inspection cost, shortage cost, order cost, holding cost using the EOQ method. The first stage in this study is to calculate the optimal order quantity value, then find the expected number of drug expirations. These results will be used to calculate the total inventory cost of five types of medical materials. for the inspection cost value, if the number of expired medical materials is above 20, the inspection cost value is not equal to zero. The calculation results found that the total inventory cost was Rp. 162,904,965, this cost is less than the actual cost of Rp. 185,843,346.00 with a difference of 12%.

Minimizing Fresh Fruit Bunches Inventory Costs Using Continuous Review System and Blanked Order System Methods

PT X is a company engaged in palm oil processing. The company's inventory of FFB raw materials is erratic, depending on the production needs. In processing palm oil raw materials, companies in the logistics or inventory department cannot be separated from the problem of FFB raw material inventory, which is part of the primary needs for company production. This company faces issues, namely the fluctuation in demand and lead time for placing orders, which can cause stockouts and shortages in FFB raw material inventories, which disrupts production process activities. The purpose of the research conducted was to conduct an analysis of raw material inventory control using the continuous review system and blanked order system methods to avoid the occurrence of raw material shortages in the raw material inventory to be used and to minimize the total inventory costs that must be incurred at the company and determine the best inventory method. The results obtained from this study were getting a safety stock of 1,638 tons and a known reorder point of 5,093 tons for the schedule of reordering FFB raw materials using the continuous review system method. Based on the results of calculating inventory costs using the constant review system method, it is the most optimal method with a minimal total inventory cost compared to the blanked order system method and the previous company policy, with savings generated by 0.10%.

Penerapan Metode Economic Order Quantity (EOQ) Pada UD MBO Bakery di Kabupaten Jember

This research is a type of quantitative descriptive research with the aim of analyzing the optimal amount of wheat flour raw material inventory, safety stock, reoder point, total cost and comparing the company's conventional method of wheat flour raw material inventory control system with the EOQ method. The analytical tools used are the Economic Order Quantity (EOQ) method, order frequency, ROP (reorder point), SS (safety stock), TIC (Total Inventory Cost), and POM-QM software. Based on the results of the analysis, it is known that in 2022 the purchase of UD MBO Bakery raw materials was 139,575 kg with an order quantity of 2,908 kg or 116 bags/order and an order frequency of 50 times/year with an average of 4 times/month and a total inventory cost of IDR 3,919,700.00. Calculations using the EOQ method obtained the optimal amount of raw material purchases in 2022 of 8,063 kg or 322 bags per order with a frequency of purchases of 17 times/year or orders every 18 days and the total cost of inventory using the EOQ method is IDR 2,419,040.81. This shows that calculations using the EOQ method can save total inventory costs of IDR 1,500,659.19.

210Pb-dating of sediments with models assuming a constant flux: CFCS, CRS, PLUM, and the novel χ-mapping. Review, performance tests, and guidelines

The 210Pb-based method has been widely used for five decades to determine absolute ages in recent sediments on the centennial scale. Decoding a chronology from the empirical data set requires a series of assumptions that define a mathematical model of the sedimentary conditions. This work aims to provide a comprehensive review of the fundamentals of the existing family of models assuming a constant flux of excess 210Pb at the sediment surface, namely the CFCS, CRS, and PLUM models, and to present the novel χ-mapping versions of the CFCS and CF models. Their performance is assessed with a selected group of five cores from literature data, with varve chronologies or independent time marks. The PLUM model did not produce reliable chronologies in any of the cores studied. The CRS model is too sensitive to an accurate estimation of the total inventory. A weighted-fit and the χ-mapping versions of the CFCS model are prone to over-represent the younger regions of the core. The CFCS model with least squares fitting and the χ-CF models performed best under the most common sedimentary conditions, which involve temporal variability in the fluxes randomly distributed in the time line. A practical strategy is suggested to identify the occurrence of such sedimentary conditions through the combined use of a set of models, providing this way further strength to the 210Pb-dating.

Predictors of Burden in Carers of Patients with Impulse Control Behaviors in Parkinson's Disease.

Impulse control behaviors (ICBs) are problematic, reward-based behaviors, affecting 15% to 35% of patients with Parkinson's disease. Evidence exists of increased carer burden as a result of these behaviors; however, little is known about the variables mediating this effect and their management. To identify factors predictive of carer burden in a cohort of patients with Parkinson's disease with ICBs to enable the development of targeted therapeutic interventions for carers. Data were collected from 45 patients with clinically significant ICBs and their carers, including levodopa equivalent daily dosage, motor and neuropsychiatric symptoms, cognitive function, and ICB severity. Carer burden was quantified by Zarit Burden Interview (ZBI). Univariate analyses were performed using the Spearman rank correlation. Linear regression was used to create a multivariate model for predicting ZBI. Univariate analysis identified significant correlations between ZBI and patient total Neuropsychiatric Inventory (NPI) (r s = 0.50), 4 NPI subscores (agitation/aggression, r s = 0.41; depression/dysphoria, r s = 0.47; apathy/indifference, r s = 0.49; and irritability/lability, r s = 0.38; all P < 0.02), and the carer 28-item General Health Questionnaire (GHQ-28) (r s = 0.52, P < 0.0005). Multivariate linear regression retained total NPI and GHQ-28 scores and were collectively predictive of 36.6% of the variance in the ZBI. Our study suggests that depressive symptoms and aspects of executive dysfunction (apathy and disinhibition) in the patient are potential drivers of carer burden in patients with ICBs. Such findings suggest the presence of executive difficulties and/or mood disturbance should point the clinician to inquire about burden in the caring role and encourage the carer to seek help for any of their own general health problems, which may compound carer burden.

A heuristic approach for multi-echelon inventory optimisation in a closed-loop supply chain

This study deals with a closed-loop supply chain where inventory levels are controlled by an order-up-to inventory policy. The system under consideration is the cylinder-packaged gas supply chain of Air Liquide company, where empty cylinders used by customers are returned to be filled again by company plants. First, we examine the goodness of fit for demand distributions based on company real data. This enables us to better characterise demands pertaining to different classes of products. Then, we formulate the multi-echelon serial inventory model to be optimised and propose a heuristic to compute the target inventory levels that helps in achieving the desired customer service level while minimising the total inventory cost. The proposed heuristic is easy to implement in the field and gives results close those obtained using a simulation-optimisation approach that is more time-consuming. Finally, we perform a numerical analysis based on company real data and compare several methods that can be used to compute the target inventory levels by varying mainly two assumptions: parameters regarding demand distributions and metrics used to assess customer service levels.

Characterization of the central nervous system penetrant and selective purine P2X7 receptor antagonist JNJ-54175446 in patients with major depressive disorder

JNJ-54175446 is a selective purine P2X7 receptor (P2X7R) antagonist that attenuates microglial IL-1β/IL-18 release. In healthy volunteers, JNJ-54175446 suppressed peripheral interleukin (IL)-1β release, and attenuated dexamphetamine-induced improvements of mood and (visuo)motor performance in a human dexamphetamine-challenge paradigm. In depression, P2X7R inhibition may dampen immune-related dysregulation of mood. These results suggest that the impact of P2X7R inhibition is most prominent in situations where mood regulation is disrupted. Total sleep deprivation (TSD) results in an acute emotional perturbation, which yields a transient antidepressant effect. In the current study, TSD was applied as a behavioral challenge to investigate whether such effects could be modulated by JNJ-54175446. This was a double-blind, placebo-controlled, randomized study to assess the safety and pharmacokinetics of JNJ-54175446 and explore its effects in patients with single episode and recurrent major depressive disorder (MDD) (N = 69) and baseline total Inventory of Depressive Symptomatology Clinician Rated (IDS-C) > 30. Patients were randomized to receive JNJ-54175446 throughout the 10-day treatment period, placebo for days 1–3 followed by JNJ-54175446 or placebo throughout. All patients underwent 36 h of TSD starting on day three until the evening of day four. The early start group was hypothesized to experience a reduced effect from TSD whilst the late starting group was hypothesized to experience prolonged effects from the TSD. JNJ-54175446 was well-tolerated and adverse events were mild to moderate. JNJ-54175446 reduced IL-1β release by LPS-stimulated peripheral white blood cells in the presence of the P2X receptor agonist benzyl adenosine triphosphate (BzATP). JNJ-54175446 did not have a significant effect on mood as assessed using the Hamilton Depression Rating Scale, 17 items (HDRS17) and the Self-rated Quick Inventory of Depressive Symptoms (QIDS-SR). However, JNJ-54175446 blunted an acute reduction of anhedonia that occurred as a result of TSD, assessed by the Snaith-Hamilton Pleasure Scale (SHAPS) and the Probabilistic Instrumental Learning Task (PILT).

Controls on the Stratiform Copper Mineralization in the Western Syncline, Upper Peninsula, Michigan

The Western Syncline hosts reduced-facies, or Kupferschiefer-type, sedimentary rock-hosted stratiform Cu deposits (SSC) in the lowermost meters of the Nonesuch Formation, which is part of a thick section of clastic sedimentary rocks that comprise the upper fill of the Mesoproterozoic Midcontinent Rift of North America. Located in the Porcupine Mountains Cu district in Upper Peninsula, Michigan, these blind deposits were discovered in 1956, but are not yet developed, although recent renewed interest may result in near-term production. The deposits are distinguished by their relatively undeformed nature and lack of superposed hydrothermal events. Prior to lithification, chalcocite mineralization replaced diagenetic pyrite within two discrete tabular, albeit discontinuous, potential orebodies referred to as the lower Cu-bearing sequence (LCBS) and the upper Cu-bearing sequence (UCBS). The Top Cu Zone transgresses lithologic boundaries, suggesting that a limited volume of Cu-bearing fluids moved vertically upwards through the unlithified stratigraphy, since reductant pyritic rocks above this zone are essentially barren of Cu. The total Cu inventory that has a reasonable expectation of economic extraction is 3678 M lbs. of Cu with 15.3 M oz. of byproduct Ag. When a cutoff grade of 0.9% Cu over a minimum thickness of 2 m is applied to justify an underground room-and-pillar mine, the LCBS and UCBS are not continuous over the Western Syncline. Sedimentology is the first-order control of potential ore and its continuity; dark-gray shales and siltstones deposited under low-energy, anoxic conditions are preferred host rocks, whose thickness must be &gt;2 m to be potential ore since host-rock thickness determines economic viability of extraction. Furthermore, stratigraphy influences the time constraints on mineralization as the lithification process impedes vertical permeability and thus the flow of Cu-bearing fluids upward through the unlithified section. Syn-sedimentary tectonic movements, likely along pre-existing buried faults, are a third-order control as the thickness of host rocks is enhanced under such conditions. Therefore, an understanding of the depositional and tectonic history throughout the Western Syncline is fundamental to understanding the limits of possible economic exploitation and to optimizing ore extraction.

Integration of ABC Analysis with Fuzzy DEMATEL and Fuzzy TOPSIS in Supplier Selection and Ranking Problems

While performing Always Better Control (ABC) analysis in an automobile industry, A category items are given higher priority, neglecting B and C category items which comprise 80% of the total inventory. Little attention to tail spend account poses problems in managing suppliers, unscheduled deliveries, and environmental issues. To address this gap a Multi-criteria decision making approach is proposed for supplier selection in each inventory class by integrating ABC Analysis with Fuzzy Decision-making trial and evaluation laboratory and Fuzzy Technique for Order Preference by Similarity to Ideal Solution. The best suppliers are selected based on criteria weights and criteria interrelationships for each A, B, and C inventory items. The study shows that managers have to focus on key criteria rather than a whole set of criteria for A, B, and C inventory suppliers thus saving costs and effort. The results show that delivery and environmentally friendly products as common and important criteria for supplier selection in each inventory items. The research results will help the decision-makers and policymakers in solving the supplier selection problems in the automobile sector and other similar sectors.

Assessment of phthalic acid esters plasticizers in sediments of coastal Alabama, USA: Occurrence, source, and ecological risk

Considering the ubiquitous occurrences and ecotoxicity of phthalates (PAEs), it is essential to understand their sources, distribution, and associated ecological risks of PAEs in sediments to assess the environmental health of estuaries and support effective management practices. This study provides the first comprehensive dataset on the occurrence, spatial variation, inventory, and potential ecological risk assessment of PAEs in surface sediments of commercially and ecologically significant estuaries in the southeastern United States, Mobile Bay and adjoining eastern Mississippi Sound. Fifteen PAEs were widely detected in the sediments of the study region, with total concentrations varying between 0.02 and 3.37 μg/g. The dominance of low-molecular-weight (LMW) PAEs (DEP, DBP and DiBP) relative to high-molecular-weight (HMW) PAEs (DEHP, DOP, DNP) indicates that residential activities have stronger impacts than industrial activities on PAE distributions. The total PAE concentrations displayed an overall decreasing trend with increasing bottom water salinity, with the maximum concentrations occurring near river mouths. These observations suggest that river inputs were an important pathway by which PAEs were transported to the estuary. Linear regression models identified sediment adsorption (measured by total organic carbon and median grain size) and riverine inputs (measured by bottom water salinity) as significant predictors for the concentrations of LMW and HMW PAEs. Estimated 5-year total inventories of sedimentary PAEs in Mobile Bay and the eastern Mississippi Sound were 13.82 tons and 1.16 tons, respectively. Risk assessment calculations suggest that LMW PAEs posed a medium-to-high risk to sensitive aquatic organisms, and DEHP posed a low or negligible risk to the aquatic organisms. The results of this study provide important information needed for establishing and implementing effective practices for monitoring and regulating plasticizer pollutants in estuaries.

Perencanaan Kebijakan Persediaan Vaksin Booster Dengan Metode Continuous Review (s,S) Untuk Mengurangi Overstock Di Rumah Sakit Tentara Kota Pematangsiantar

Pematangsiantar City Army Hospital is one of the state-owned health facilities that provides booster vaccination services with 4 types of booster vaccines available, namely sinovac, astrazeneca, pfizer and moderna. The uncertain level of demand for booster vaccines causes the Pematangsiantar City Army Hospital to require booster vaccine inventory policy planning using the continuous review (s,S) method to prevent overstock which results in considerable cost expenditures. From the calculation of booster vaccine inventory control using the continuous review method (s,S), it is obtained that the total inventory cost has a significant percentage change. For the type of sinovac, the percentage change in total inventory costs reaches 92% of the total inventory costs in the existing conditions, for astrazeneca reaches 58% of the total inventory costs in the existing conditions, for pfizer reaches 60% of the total inventory costs in the existing conditions, and for moderna reaches 95% of the total inventory costs in the existing conditions. The results of the calculation of the total cost of inventory with continuous review (s,S) can provide a decrease in costs incurred by the Pematangsiantar City Army Hospital. This is because the continuous review (s,S) inventory policy minimises the cost of vaccine shortages which are quite costly.

Optimasi Biaya Pengendalian Persediaan Alat Suntik (Spuit) Dengan Metode Optimisasi Robust Menggunakan Aplikasi Python Di RSUD Dr. Pirngadi

Inventory control is very important for companies because without proper inventory control the company will experience problems in meeting consumer needs both in the form of goods and services produced by the company. RSUD Dr. Pirngadi is one of the companies that uses conventional methods to calculate the total cost of inventory so that the costs incurred both for ordering syringes and storage costs are still high, therefore it is necessary to control the inventory of syringes which aims to minimise inventory costs so that company goals can be achieved. In solving the problem of controlling inventory costs to minimise total inventory costs, namely using robust optimisation. Robust optimisation is an optimisation model that contains uncertainty data to obtain the right solution using linear program solving. The results of research at the RSUD Dr. Pirngadi obtained the total cost of inventory according to company policy for the use of 3 mL Terumo syringes is Rp.426,104,665 while the robust optimisation method is Rp.319,647,106 so it can be concluded that by applying the robust optimisation method to the company can save inventory costs of Rp.106,987,599 or 25%. Furthermore, the total inventory cost of using a 5 mL Terumo syringe according to company policy is Rp.208,402,454 while the robust optimisation method is Rp.166,608,139 so it can be concluded that by applying the robust optimisation method to the company can save inventory costs of Rp.41,794,315 or 20%.