cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.14457/cu.the.2016.127
title: Marker planning for fabric cutting with sewing schedule constraint in mass customization context

description: The objective of this research is to develop heuristics for marker planning problem within a sewing schedule under mass customization production context. In this context, a number of sizes and an amount of demand in each size are varied in a wider range than a mass production system but with lesser total demand. The proposed problem is divided into two subproblems. The first subproblem corresponds with the cost dimension of a marker planning. Hence, the objective is to minimize the total cost related to a number of markers and excessive units. The second subproblem aims to integrate a sewing schedule into marker planning. Therefore, the objective is to minimize a work-in-process inventory workload. The initial solution from the first heuristic is determined by an LP relaxation of marker planning. Then, it is improved by a greedy-based algorithm. This algorithm focuses on reducing an unnecessary plies and adjusting marker patterns. Furthermore, initial solutions are randomized to avoid getting stuck with a local optimum. The second heuristic further improve a first heuristic’s solution by focusing on rearranging marker patterns in order to correspond with a sewing schedule. To measure performance of the proposed heuristics, the first heuristic is tested with many problems. For small-and medium-sized problems, the heuristic can reach to the optimal solutions in all problems while with large-sized problems, heuristic solutions are better than solutions from GA which can reach to optimal solutions as well. The second heuristic is tested with large-sized problems. The second heuristic can perform better than GA method.
DOI: 10.14457/cu.the.2016.128
title: REINFORCEMENT OF NATURAL RUBBER WITH COAL FLY ASH AND SYNTHETIC ZEOLITE

description: Natural rubber (NR) is a biopolymer consisting primarily of isoprene units produced by plants. Due to its high elasticity property, NR has been widely used for manufacturing of many industrial products. Generally, the addition of fillers in NR is required for improving its properties. This work focuses on the preparation of NR composite films by using coal fly ash and synthetic zeolite from coal fly ash as filler. The objective is to exploit coal fly ash, industrial waste as a raw material for value-added products. It can also help reduce the area for disposal of coal fly ash by landfill. Moreover, this is not only to add value of coal fly ash but also the mechanical properties of the NR composite films were improved. The NR composite films were prepared via a latex aqueous micro-dispersion process. The morphology of NR composite films combing with CFA, CFAT, SA and ZA at different loading contents were characterized by field emission scanning electron microscopy (FE-SEM). The chemical structure of NR composite films were investigated Fourier Transform Infrared (FTIR) Spectroscopy. The mechanical properties, crystallinity, water absorption capacity and toluene uptake of NR composite films were analyzed. The results demonstrated that at a suitable loading range, the mechanical properties (Young’s modulus, tensile strength, elongation at break) of the composite films were better than those of NR films. The composite films, especially NR-CFA also demonstrated considerably more resistance and structural stability in both water and toluene. As compared to the NR film, the WAC (water absorption capacity) and TU (toluene uptake) of the composite films were decreased. However, according to hydrophilic property of the fillers, the WAC values of the composite films were slightly increased with the increase of filler loading from 2-20 phr.
DOI: 10.14457/cu.the.2016.129
title: THE STUDY OF EFFECTS AND MECHANISMS OF INDUSTRIAL CONTROLLED FACTORS ON ELECTROLESS NICKEL IMMERSION GOLD (ENIG) PLATING PROCESS

description: This research aimed to study the effects of the factors and mechanisms which were controlled by the industry on the electroless nickel immersion gold (ENIG) process including pretreatment step and condition used in ENIG. The thickness analysis of nickel and gold layers by X-ray fluorescence spectrometry (XRF) found that increasing the concentration of precursors, chelating agents, the alkalinity in the controlled range, temperature, and decreasing of oxides on the surface of the substrate resulting in a thick layer of nickel and gold. Also the phosphorus on the nickel substrate caused the thinner layer of gold. For the Ni/P alloy, the nickel composition ratio measured by energy dispersive X-ray spectrometer (EDX) would be greater due to increasing of nickel salt, alkalinity in the EN plating solution or temperature. However, increasing the temperature more than 90 oC caused decomposition of EN plating solution. Moreover, the decreasing of reducing agent resulted in increasing of nickel composition ratio of nickel alloy. The factors affected the roughness and morphology of the nickel surface measured by scanning electron microscopy (SEM) and stylus containing the morphology of the substrate, the gas bubbles generated by the plating reaction which affected the flow of the plating solution and agitation. In the case of gold roughness was based on the nickel surface roughness. The too thick gold plating layer resulted in the dropping of the adhesion between gold layer and nickel surface. The sensitive parameters of EN plating were by-product of plating reaction and pH of EN solution. For IM plating, the sensitive parameter was pH of IM plating solution.
DOI: 10.14457/cu.the.2016.130
title: Hydraulic Fracturing Designs for Low Permeability Gas Condensate Reservoirs Having Different Compositions

description: Gas condensate reservoirs have been challenging all researchers in petroleum industry for decades because of their complexities in flow behavior. After dew point pressure is reached, gas condensate will drop liquid out and increase liquid saturation near wellbore vicinity creating production loss due to the phenomenon called condensate banking or condensate blockage. Many studies indicate the damage from condensate banking in many gas condensate fields all over the world and it can be more severe if the permeability of the reservoir is low. Hydraulic fracturing in horizontal well has been proved to be a reliable method to mitigate condensate banking and to increase productivity of condensate well by means of pressure redistribution in the near wellbore vicinity. In this work, compositional reservoir simulator had been implemented to study several designs of hydraulic fracturing in low permeability condensate reservoir. The objectives of this study are to study the effect of parameters of dimensionless fracture conductivity with different fluid compositions and saturation profile near wellbore vicinity had been observed. The results indicate that fracture width has impact on controlling inertial effect. Increasing fracture width improves condensate productions in both lean and rich condensate compositions to 18.45% and 12.15% compared to non-fracture case. While, higher number of fractures allow larger contact area between fracture and reservoir and increasing condensate production to 18.45% and 11.68% in lean and rich condensate compositions respectively. Moreover, number of fractures also plays an important role in the condition of having the same Stimulated Reservoir Volume (SRV). The investigation of fracture permeability shows small benefit from increasing fracture permeability from 50,000 mD to 150,000 mD because fracture permeability at 50,000 mD is already high enough compared to reservoir permeability at 0.2 mD. In addition, from the study of condensate saturation near wellbore indicates that condensate banking can be reduced effectively with the introduction of hydraulic fracturing. Especially in rich condensate composition where revaporization occurred. The couple effect of revaporization and hydraulic fracturing has benefit on decreasing condensate banking more than considering the effect of revaporization alone.
DOI: 10.14457/cu.the.2016.131
title: SIMPLE MODEL FOR APPROXIMATION OF MUTUAL COUPLING IN MICROSTRIP PATCH ARRAY

description: A relatively simple and efficient empirical formulation for the estimation of mutual coupling between two microstrip patch antennas has been proposed in this thesis. The formulation is constructed based on the asymptotic behavior of the electromagnetic wave excited by an electric current on a grounded substrate. It is expressed by a few terms of cylindrical wave functions of two variables, which are center-to-center spacing and azimuthal angular separation between two antennas. The formulation contains coefficients which need to be determined at once, for any given antenna geometry and operating frequency, by matching with few sample values of mutual impedance for several antenna separations using the least square method. The latter are calculated by a rigorous full-wave analysis using a commercial software. The formulation with the obtained coefficients can then be used to estimate the mutual coupling between two similar antennas for any arbitrary separations. The proposed formulation is expected to be far more efficient than the exact solution due to its simple closed form. The proposed approach can be employed to efficiently estimate the mutual coupling between any elements of a microstrip patch array antenna. Some numerical examples are given to illustrate the applicability, validity, and efficiency of the proposed approach. The good agreement of the mutual impedance estimated by the present approach and that obtained by a rigorous full-wave solution has been demonstrated.
DOI: 10.14457/cu.the.2016.132
title: Effects of Polymer Adsorption and Desorption on Polymer Flooding in Waterflooded Reservoir

description: Polymer Flooding is one of the most well-known methods in Enhanced Oil Recovery (EOR) technology which can be implemented after either primary or secondary recovery. Polymer can lower the mobility ratio of the displacement mechanism by means of increasing viscosity of injected water. Therefore, polymer flooding can increase volumetric sweep efficiency. Moreover, polymer adsorption onto rock surface can decrease permeability contrast in reservoir with high heterogeneity. Due to reduction of the absolute permeability, effective permeability to water is also reduced. Once polymer is adsorbed onto rock surface, polymer can also be desorbed when different fluids are injected. This study focuses on polymer adsorption/desorption behavior in the reservoir as well as effects on operating parameters and interest reservoir conditions. Reservoir simulator called STARS® commercialized by Computer Modeling Group is utilized to assess interest effects. The results show that performing polymer flooding after water pre-injection sooner can increase oil recovery factor in the shortest period and similar results are also obtained from higher injection rate. The difference of polymer mass injected into the reservoir, represented by polymer concentration affects the optimum polymer slug size. Higher polymer concentration requires smaller slug size of polymer to attain constant oil recovery factor, vice versa. Polymer desorption causes polymer re-employment from the previously adsorbed onto rock surface, resulting in improving of sweep efficiency in the further period of polymer flooding process. However, the optimum value of polymer desorption degree in difference polymer concentration exists. When using high polymer concentration, total polymer desorption allows chasing water to bypass polymer slug, causing adverse effect on sweep efficiency. In reservoir with variation in permeability, polymer can be injected to retard early water breakthrough. However, degree of polymer desorption should be zero to allow permanent adsorption as reduction of relative permeability to water can be maintained to ensure slow movement of inject fluid. Magnitude of polymer adsorption does not affect much on oil recovery factor when degree of polymer desorption is varied. In high magnitude of polymer adsorption, zero polymer desorption causes less effective polymer to maintain viscosity whereas effects of reduction of relative permeability dominates effects of maintaining viscosity in case of 50 percent polymer desorption. Combination of total desorption with high residual resistant factor shows favorable results. Sweep efficiency is improved also at boarder of flood pattern and moreover, diverting of chasing water to border zones results in very favorable sweep efficiency.
DOI: 10.14457/cu.the.2016.133
title: SETUP TIME IMPROVEMENT FOR A FASTENER MANUFACTURING PROCESS

description: The objective of this research is to reduce setup time of bolt forming process in a fastener manufacturing company. The essential requirement to improve setup time arises from value stream mapping of current production process. Cause and effect diagram is used for problem analysis of setup operation. The improvement area of this research is selected by weight score matrix based on information from the analysis. Methodology is divided into three phases; planning phase, improvement phase and implementation phase. Basis and necessary information of this research are defined in planning phase. In improvement phase, setup time improvement framework is developed consisting of two steps improvement. The first step improvement applies a well-known tool for setup time reduction, Single minute exchange of dies (SMED). For the second step improvement, lean tools and techniques are used to further analyze setup operation and improve setup time including Pareto, Five Whys, Spaghetti diagram, and 5S. Finally, full improvement implementation is successfully performed in the implementation phase. As a result of this research’s improvement, setup time of bolt forming process is able to reduce from 4 hours and 9 minutes to 1 hour and 14 minutes. The total of 2 hours and 54 minutes is accounted for 70 percent in setup time reduction. Furthermore, the company gains various benefits including ability to produce smaller batch size in order to avoid overproduction, reduction of waiting time and inventory level, and improvement of production process flexibility and responsiveness.
DOI: 10.14457/cu.the.2016.134
title: STATIC ONE-TO-ONE MULTI-VEHICLE PICKUP AND DELIVERY PROBLEM WITH MULTIPLE DEPOTS

description: The research describes a static case of the pickup and delivery problem with multiple depots and proposes a solution approach that forces a combination of requests in a particular route. To solve the problem, the model is implemented using General Algebraic Modelling System (GAMS) with CPLEX as the solver. Euclidean distances are considered as the total cost between nodes. Instances based on existing studies are used for computational experiments. Best-bound search and depth-first search methods of the branch-and-bound algorithm are also compared. Results of the trials implemented in GAMS are presented in the study. The optimal solutions found with routes having combined requests show significant distance reduction compared to the typical individual service of one request per route. Results also show that as the number of allowed requests in one route is increased, the effect of the number and variation of depots also decreases. The main contribution of this research are applications in GAMS that can solve the static case of the messenger problem in a multi-depot variation, a setup with few available literature. The study can be beneficial for logistics companies especially those of which specializing in pickup and delivery services.
DOI: 10.14457/cu.the.2016.135
title: Inventory Policy Improvement for a Kitchenware Trader

description: The research objectives are to improve inventory policy for a kitchenware trader in order to reduce the inventory level and improve internal operations. The product movement in 12 months of 2015 for 738 SKUs is evaluated and categorised. Five groups are 1) Non-moving stock 2) Stock with no sales last 6 months 3) Short-period stock 4) New product stock and 5) Remaining185 SKUs. Strategic managements for each group are proposed. The remaining 185 SKUs are classified based on operational aspect by using ABC Pareto. The continuity of demand is the first criteria for sequencing the importance of products, since it can divide groups of continuous and intermittent demand items. The second criteria is number of order in 2015. The third and fourth criteria are the value of sales and average inventory value, respectively. Forecasting approaches and error indicators, and inventory system are proposed. Periodic review policy is proposed for all groups because of high transportation costs. The simulations of the proposed methodology are performed for the policy assessment by using Microsoft Excel. Actual operations in five months between January to May, 2016 are compared with the implementation of the proposed policy. The results show the reduction of inventory level for group A and B, while the service level of the proposed policy can perform without stock out period. Finally, the slow moving products in group C cannot be concluded as it is considered inadequate historical data and comparison period.
DOI: 10.14457/cu.the.2016.137
title: Effects of iron and inflammation on astrocytes functions

description: Iron accumulation and inflammation are present in a variety of neurodegenerative diseases include Alzheimer's disease and Parkinson's disease. Nowadays it has not yet known what the specifically causes neurodegeneration. There is probably not one single, but several factor are important to describe the etiology of these diseases. In this study, ferric ammonium citrate, pro-inflammatory cytokines including interleukin 1β and tumor necrosis factor alpha and combined were investigated the altered astrocytes functions. The results showed that FAC and combination of cytokines were markedly induced intracellular iron accumulation, free iron and reactive oxygen species, while the proliferation was inhibited in the presence of combination. In addition, the results demonstrated that iron enriched astrocytes alters the genes expression profiles involved in iron homeostasis by increased the expression of iron importer and storage genes couple with decreased in iron exporter gene. According to this condition, the rearrangement of astrocytes cytoskeletons were observed in an alteration of intermediate filaments, GFAP and vimentin, which refer to an initially activated astrocytes. Moreover, the combination of FAC and cytokines was able to induce the expression of the inflammation response genes including IL-1β, IL-6 and TNF-a. At the same time, the presence of FAC and combination of cytokines were significantly increased cytokines levels including IL-1β, IL-6 and TNF-a and glutamate secretion compared to unexposed control cells. Taken together, these findings suggest that astrocytes in neurodegenerative disorders are oxidatively stressed due to their tendency to accumulate iron, express and release more of cytokines and glutamate that can be harmful to neuron.
DOI: 10.14457/cu.the.2016.138
title: Role of autotaxin for the pathogenesis of liver fibrosis in biliary atresia

description: Biliary atresia (BA) is one of the most common causes of neonatal cholestasia. The etiology of BA remains mysterious. Lack of reliable noninvasive diagnostic biomarkers of BA may leads to delayed diagnosis and worse patient outcome. Hence, the identification of noninvasive biomarkers to assess liver fibrosis is desirable. The main aim of this study was to explore various contributors for hepatic dysfunction including autotaxin (ATX), relative telomere length (RLT), global DNA methylation and oxidative stress whether these biomarkers could be related to the pathogenesis of liver fibrosis in BA. One hundred and fourteen post operative BA patients and 114 age-matched healthy controls were enrolled. We found that BA patients had higher circulating ATX and liver stiffness than controls. Our findings showed that elevated circulating ATX was associated with status of jaundice, hepatic dysfunction, and liver stiffness in postoperative BA. In addition, the current study provides evidences for up-regulation of ATX mRNA expression in liver specimens of BA patients compared to those in controls. The up-regulation of ATX expression in BA liver samples was performed with immunohischemical detection of ATX antigens within the liver bile duct epithelia and the hepatocytes. ATX mRNA expression was also significantly elevated and correlated with a decrease in ATX promoter methylation in BA patients compared to the controls. Moreover, this study supports the association between RTL in peripheral blood leukocytes and higher risk of liver fibrosis in BA. RLT in blood leukocytes was also associated with disease severity, showing that BA patients with advanced-stage exhibited excessive telomere shortening. Additionally, this study reported that, independent of risk factors, hypomethylation of retrotransposable DNA elements (Alu and LINE-1) was associated with shorter telomeres, elevated oxidative DNA damage, and a higher risk of liver fibrosis in BA. Based on the aforementioned findings, combinations of circulating ATX levels, hepatic ATX expression, relative telomere length, global DNA methylation, and oxidative DNA damage could serve as possible noninvasive biomarkers reflecting the disease severity and the development of liver fibrosis in the post Kasai BA patients. Autotaxin could play a crucial role in the pathogenesis of liver fibrosis in chornic liver disease including biliary atresia.
DOI: 10.14457/cu.the.2016.139
title: Relationships between personal factors, self-efficacy, psychological empowerment, organizational support, and professional behavior of Indonesian nurses, west java province, Indonesia

description: The purposes of this descriptive research were to 1) study professional behavior and examine relationships between personal factors (educational level and working experience), self efficacy, psychological empowerment, organizational support, and professional behavior of Indonesian nurses, West Java province, Indonesia. Samples were 160 professional nurses included in this study. Study instruments were Personal factors, General Self Efficacy Scale (GSE), Perceived Organizational Support (POS), Psychological Empowerment Questionnaire (PEQ), and Professional Behavior Questionnaire (PBQ) examined content analysis by a panel of experts. The reliability with Cronbach’s alpha of GSE, POS, PEQ, and PBQ were .748, .888, .709, and .971 respectively. Data analysis were by using frequency, percentage, mean, standard deviation, Pearson correlation, and Chi-square. The study findings were as follows: 1. Professional behavior of professional nurses was at good level (x = 4.00, SD =0.47). 2. Personal factors including working experience and educational level were found: 2.1 Working experience was moderately and positively related to professional behavior at significance level of .05. (r=.499). 2.2 Educational level was moderately related to professional behavior at significance level of .05. (x2 = 20.36). 3. Organizational support was lowly and positively related to professional behavior at significance level of .05. (r=.210). 4. Psychological empowerment was moderately and positively related to professional behavior at significance level of .05. (r=.558). 5. Self efficacy was moderately and positively related to professional behavior at significance level of .05. (r=.576). The findings indicated that organizational support and psychological empowerment were positively related to professional behavior. Thus, nurse executive should support all materials for nursing practice and enhance psychological empowerment for professional nurses in order to increase professional behavior.