37 research outputs found
Development of Storage Allocation Models in a Warehouse
No full textThis thesis is submitted to the Department of Industrial Engineering and Management, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Science in Engineering in Industrial Engineering and Management, December 2011.Cataloged from PDF Version of Thesis.Includes bibliographical references (pages 62-66).The developments in warehouses have significantly influenced the existing paradigms in
inventory research. Unfortunately, the attention paid by researchers in inventory theory to
the management of storage systems such as warehouses has been relatively limited. Often,
it was considered mainly to be a technical issue and therefore belong to a different area,
i.e., material handling research. The warehouse problems can be classified mainly into two
groups i.e., the design problem and the operational problem. The design problem deals
with the issues such as over all structure, sizing and dimensioning, department layout,
equipment selection, and operation strategy of the warehouse. On the other hand, the
operational problems deal with receiving and shipping, and storage and retrieval (order
picking). Chapter 2 provides a brief description of the literature related to operational
problems. Maintenance environment warehouse is very similar to production warehouse
where spare parts are stored and retrieved. In such an environment, allocation of space and
assignment of spare-parts in a warehouse is a vital problem for sound operation of a
warehouse. Miss-allocation of spare-parts takes huge time to find out parts. This problem
causes extra time consumption and money expenditure for the involvement of labor for
long time and creates risk of unavailability of spare parts that lead to improper maintenance
or repair of machines. Generally, allocations of items are done in alphanumerical order
without regard to issue frequency, size, weight or volume. As a result, it will be creates
problems in issuing/retrieving the spare parts with minimum waste of time & effort.
The objective of this research is to study the developments of operational problems related
to production warehouse especially for maintenance environment. Chapter 3 is devoted to
develop an efficient methodology to identify the similar parts i.e., sparepart_set (SPS) that
can be grouped together and be kept in one place. Doing so, it may increase the efficiency
of the storage and retrieval. The weight (popularity index) is used to identify the
Spare_part_set as slow moving or fast. The weight of a spare_part_set is the summation of
all item's frequency of usages in year. By considering weight, higher weight SPS (fast
moving) should be kept near to issue counter and less weight (slow moving) SPS is to be
placed far from counter.
In chapter 4, the model is simulated for hypothetical warehouses. The objective of the
experiment is to investigate the performance of the methodology described in the previous
chapter in terms of travel distance to collect all the items of a demand. For this purpose,
three hypothetical warehouses are considered. The first one, in which the spare parts are
stored in alphanumerical order and the second one, in which the spare parts are stored
according to the algorithm described in chapter 3 and in the third one, spare part are stored
randomly. The details of the experiment and the results of the experiment are presented in
chapter 4. The performance of the algorithm is evaluated in terms of the average travel
distance needed to collect an order of SPS. It is found that the average travel distance is
minimum (20%) less for our proposed methodology.
Lastly, in chapter 5, conclusions and some recommendations are presented.Syed Ariful IslamMaster of Science in Engineering in Industrial Engineering and Managemen
Behavioral and biochemical effects of fluoxetine on Poecilia reticulata: A relaxing state or an unapparent crisis?
No full textFluoxetine is an antidepressant used for the treatment of depression and anxiety disorders. We hypothesized that fluoxetine may positively influence the well-being of fish. We used Poecilia reticulata as a model organism and evaluated the behavioral, ecological and biochemical alterations following fluoxetine exposure at 0.05, 2.0, and 80 μg/L. For the behavioral analysis, we assessed swimming patterns, aggressiveness, social interactions and predatory behavior in a novel tank. Avoidance and colonization were evaluated as behavioral endpoints using the non-forced HeMHAS (Heterogeneous Multi-Habitat Assay System) as a novel approach to assess behavioral endpoints. The biochemical approach was based on the biotransformation enzyme activity (EROD and GST), anti-oxidative defense markers (GPx and GSH), oxidative damage indicators (LPO and DNA damage) and neurotoxicity (AChE activity). We found that the swimming patterns, aggressiveness and social behavior were reduced from 2 μg/L (p < 0.001) and the time spent by P. reticulata in the top and bottom areas differed significantly from 0.05 μg/L (p < 0.05). Additionally, organisms exposed to fluoxetine required more time (significantly from 2 μg/L; p < 0.001) to attack all the Daphnia sp. provided as prey. Further, in the colonization and avoidance tests, P. reticulata did not display colonization behavior (50–60 % time spent in the control compartment), and exhibited only weak avoidance responses, instead appearing to be either lethargic or in a relaxing state. The biochemical analysis showed that GST and LPO levels were elevated (p < 0.001), while both the GPx and GSH were reduced (p < 0.05).This study is part of the BeingHavior project (PID2022-137402OB- I00) funded by the Spanish Ministry of Science, Innovation and Universities (MCIN/AEI/10.13039/501100011033/FEDER, EU). The authors would like to acknowledge the Science and Technology Fellowship Trust (STFT), GoB for providing doctoral funding. The authors thank Jon Nesbit for his English revision of the text. The authors also express gratitude to Dr. Syed Muneeb, Duda, Andressa, Joel, Dr. Md Khurshid Alam Bhuiyan, Dr. María Úbeda, David Salvatierra, María Pilar Gonzalez for their support during the research. Camilo Dias Seabra Pereira thanks FAPESP (Process 2022/06151-0) and CNPq for Productivity Fellowship.Peer reviewe
A 24-year-old man with fibrodysplasia ossificans progressiva: clinical challenges and management
No full textFibrodysplasia ossificans progressiva (FOP) is a rare, disabling genetic disorder characterized by progressive heterotopic ossification of skeletal muscles and connective tissues. It is recognized as the most disabling condition of extraskeletal bone formation. The worldwide prevalence is approximately 1 in 2,000,000, with no ethnic, racial, gender, or geographic predilection. The hallmark clinical features include congenital malformation of great toes (commonly bilateral hallux valgus) and recurrent episodes of heterotopic ossification, often triggered by trauma or occurring spontaneously. Pathogenesis involves dysregulated bone morphogenetic protein (BMP) signaling due to mutation in the ACVR1 gene. Here we report a case of 24-year-old male with classical FOP, presenting with bilateral deformities of the big toes and progressive ectopic ossification. Despite advances in understanding the molecular mechanisms of the disease, there are currently no definitive preventive treatments. Early recognition of FOP, particularly by pediatric clinicians, is critical to avoid exacerbating factors, such as invasive procedures or trauma that may accelerate disease progression. This case report highlights the importance of clinical vigilance and continued research into therapeutic options for this devastating condition.
Pattern of Pre-Hospital Treatment Received by Cases of Pesticide Poisoning
No full textBackground: Prehospital treatment following acute pesticide poisoning is not optimal and mortality following such poisoning is high in Bangladesh. Method: It was a prospective study in which pattern of pre-hospital treatment received and outcome of pesticide poisoned patient were studied at one adult medical unit of Dhaka Medical College Hospital from October 2005 to June 2006. Results: The number of cases of pesticide poisoning were 60 (1.98%) of 3030 admitted patients. The mean age was 24.7±8.8 years. Most of them (40, 66.7%) were male. The incidence of poisoning was high among students (11, 18.3%) and housewives (10, 16.7%). The most common cause of poisoning was intentional (55, 91.7%). Familial disharmony was underlying cause in 27 (45%) patients. More than half of the patients (41, 68.3%) purchased the poison self. 25 (41.7%) patients got first contact with physician within 30 minutes of poisoning. In majority cases (45, 75%) first contact health care provider was government hospital. Only 22 (36.7%) patients received first aid before arrival to present hospital. Among them, 19 (31.7%) patients received induced vomiting by ingestion of tamarind water or lemon water or soap water or putting finger or other substances (cow dung, human excreta etc.) in mouth and 3 (15%) patients received home remedy like milk, raw egg etc. The overall mortality was 16.7%. Conclusion: Measures should be taken to increase the awareness among general population regarding the first aid following pesticide poisoning
Strengths of concrete made with white and gray cements
No full textCement is one of the most important binding materials in civil engineering field. In construction
industry cement is having higher demand day by day. Higher consumption of cement in construction
industry leads to higher pollution. That’s why engineers recommend such cement which will be
environmentally friendly, have aesthetic properties, economical and will be sufficient enough to give
the desired strength. Generally, there two types of cement available in our local market (gray, white).
Recently it is claimed by some of the experts that gray cement concrete gives more strength than white
cement concrete. The study mainly aims at justifying the view by comparing the strength of concrete
made of white and gray cement. For this purpose, 144 cylinders were cast (4” X 8”) in total using mix
ratios 1:1.25:2.5 and 1:1.5:3 for 40% and 50% water cement ratios and 7-, 14- and 28-days curing
period. By following these criteria 72 cylinders had been cast and crushed both for white cement and
gray cement concrete separately. Results show that initial strength gaining rate of white cement
concrete is very much higher than gray cement concrete but after 28 days curing period’s ultimate
compressive strength of gray cement is more by 156 psi (minimum), 205 psi (maximum) and 181 psi
on an average where tensile strength by 48 psi (minimum), 91 psi (maximum) and 75 psi on an average
than of white cement concrete.https://www.iebbd.org
Supply Chain and Logistics of Fish: A Case Study of Jamalpur District Markets in Bangladesh
No full textFishery sector plays a vital role in the socio-economic development of Bangladesh. In the fish economy of Bangladesh, one of the most flourishing traffic activities is fish marketing. This study was aimed to investigate the fish species availability, supply chain, quality loss, price behavior and constrains associated with fish marketing in order to provide better suggestion for efficient fish marketing in Jamalpur district of Bangladesh. Data were collected form Sadar upazila markets by using a structured interview schedule, focus group discussions (FGD) and key informant interviews (KII) with the stakeholders involved in supplying fish from farm to fork, such as- aratdars, retailers, and consumers during 2020-21. A total 78 fish species were found (72 Fresh water and 2 Marine water), among them 20 frequently, 17 less amount, 25 occasionally, and 16 species were rarely available in the market. It was estimated that 72% fish species were sourced from culture fishery whereas 28% were from capture fishery. About 91.5% fishes in Jamalpur markets were supplied locally, whereas rests were from other districts. The post-harvest quality losses of fish in the sampled markets were assessed which indicate that small indigenous species (SIS) spoiled quicker than medium to large sizes fishes due to different factors. The price behavior of the fish market influenced by the demand of the fish species, quality, size, catching sources (culture fishery or capture fishery) and the purchasing time (beginning, middle or last time of market). The study found positive correlation between the market price and fish quality. Several problems of fish market were identified resulting consumer dissatisfaction and financial losses for fish traders. Considering the importance of fish market to the economy, this study suggested to take necessary steps for establishing modern fish market to ensure the adequate quality maintenance of fish with efficient marketing
