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"This research was conducted at P.T. “ED” Aluminium, Yogyakarta, an industrial aluminum foundry that produces manually operated cooking appliances. The workers complain of muscle pain and fatigue, and of always having to pursue production targets in order to fulfill goods shipment deadlines. Also evident was the unergonomic work system, where the liquid aluminum was often spilled due to workers having to adopt an unnatural work posture when pouring the liquid aluminum into molds. Therefore, the researchers’ aims were to improve the operator’s working posture, reduce the workload, eradicate musculoskeletal complaints, improve time efficiency, and increase productivity by redesigning the liquid aluminum pouring tools using an integrated participatory ergonomics method combined with an appropriate technology (AT) concept. Furthermore, ergonomics intervention was conducted in the redesigning of the pouring tools. The result was an ergonomic liquid aluminum pouring tool. The ergonomics intervention results from use of the newly designed pouring tools allowed for a more natural working posture, improvement in the workload category from heavy to medium, a 26.13% reduction of the workload, and a 19.64% reduction in musculoskeletal disorders. Time efficiency increased by 25.81%, and productivity increased by 26.60%."

"The Aluminum 7075 (Al 7075) alloy is a precipitation hardening material instead of a strain hardening material. These mechanical properties are of a particular microstructure obtained by thermo-mechanical treatments. Among other things, this is a complicated microstructure which is responsible for the mechanical performance. The evolution of the mechanical properties of aluminum alloys is dependent on aging time parameters after heat treatment. In this study, the material has undergone a tempering heat treatment followed by a series of tensile tests. The experimental data (tensile curves in three directions during maturation time) is used to describe the evolution of the mechanical characteristics in terms of loading directions and maturation time, denoted respectively as: Ψ and t. The tensile curves are the source of data to begin the problem of identifying the behavior law of studied material using Barlat?s model and Hollomon?s isotropic hardening law. Thus, from the identified parameters (anisotropy coefficients and hardening coefficients), the evolution of the Lankford coefficient, deformation rate and load surfaces during the maturation time for three load directions (0°: rolling direction, 45° and 90°) are described. This study allows optimizing the response of the aluminum alloy to plastic strains, resulting from forming processes measured against the best time during maturation and the best load direction."

"Literature studiesindicate that information technology (IT) clusters encourage innovation andincrease firm-level productivity by providing external economies and facilitatingjoint action for its members. The purpose of this study is to identify theexternal economy and joint action factors that affect firm innovation andproductivity in the IT cluster. A research model was developed based on earliermodels of joint action and external economies. The model consists of three externaleconomy related factors, i.e., access to skills, finance, and infrastructure, aswell as three joint action related factors, i.e., vertical, horizontal, andresearch and development (R&D) cooperation as the independent variables,firm innovation as the intervening variable, the firm?s absorptive capacity asthe moderating variable, and firm productivity as the dependent variable. Datacollection was conducted through a survey with respondents from 32 IT firmslocated in three clusters in Bandung and one cluster in Cimahi (West Java ?Indonesia). The partial least square (PLS) approach was used for hypothesestesting. The results indicate that horizontal cooperation, access toinfrastructure, and access to skill have a positive impact on productivity,while horizontal cooperation and R&D cooperation have a positive impact oninnovation. Finally, firm innovation is proven to positively influence firmproductivity."

"The kinetics of aluminumleaching from sludge solid waste (SSW) using hydrochloric acid at differentleaching temperatures (30-90°C) was studied. A mathematical model was developed based on ashrinking core model by assuming first-order kinetics mechanisms for leachingand an equilibrium linear at the solid-liquidinterface. The proposed model is suited to fit experimental data with threefitting parameters and to simulate the leaching of aluminum from SSW, which wasvalidated with the mass transfer coefficient (kc, cm/s),diffusion coefficient (De,cm2/s), and reaction rate constants (k, cm/s). The evaluated kc,De, and k are expected to follow an increasingtrend with increasing temperature. The correlation coefficient ≥ 0.9795, theroot mean square error ≤ 0.399, the mean relative deviation modulus ≤ 6.415%,and the value of activation energy is 13.27 kJmol-1. The proposed model could describe the kinetics ofaluminum leaching from the SSW DWT in accordance with test parameters andrelevant statistical criteria. Valuable information on the results of this workcan be given for the purposes of the simulation, optimization, scaling-up, anddesign of the leachingprocess."

"Thedevelopment of the construction industry in Indonesia has been substantiallycontributing to the enhancement of the social and economic development of thepeople. However, its expansion has also become an issue, as the developmentmight be implicated in the abuse of environmental sustainability when thepractices of conducting the construction project abandon the rules and regulationsof sustainable green construction concepts. Therefore, this study attempted tointroduce a quantitative assessment tool called the Green Construction SiteIndex (GCSI) to evaluate the performance of an ongoing project to meet thesustainable green construction concept. The aim of this study was toinvestigate the effectiveness of GCSI as a quantitative assessment tool tomeasure the implementation of the green construction concept conducted byongoing projects. Data were collected by onsite direct observation, interviewswith key personnel, and project documentation review. Data were organized andanalyzed using descriptive elaboration. The results showed that three aspects,the Efficiency Index (IE), Productivity Index (IP), andAwareness Index (IA), were effective in assessing 10 ongoingconstruction projects, categorized as Non-Commercial Non-Residential Building,Commercial Residential Building, and Commercial Non-Residential Building. Theindex generated using GCSI, upon assessing 10 buildings, was 3.39 and fell intothe Good category with IE = 3.51, IP = of 2.86, and IA= 3.84. Another finding shows that the Project Organizational CommitmentIndex (POCI) to the indicator ofthe GCSI was 3.31 (Good category) with IPOL = 3.36, IPRO =3.49, and IPRAC = 2.75. The capability of the GCSI to identify threeaspects within a construction project simultaneously and comprehensivelysuggests the importance of its function as an effective tool that givesbenefits to not only the contactors, but also to the authorities that controlthe green construction?related performance. Therefore, the GCSI is expected tobe applied as a standardized reference by both the construction industries andregulating authorities. Despite its satisfactory findings, the GCSI needs to befurthered to achieve its reliability and validity to be adopted internationally."

"An efficient Region-Based Image Retrieval (RBIR) system must consider query region determination techniques and target regions in the retrieval process. A query region is a region that must contain a Region of Interest (ROI) or saliency region. A query region determination can be specified manually or automatically. However, manual determination is considered less efficient and tedious for users. The selected query region must determine specific target regions in the image collection to reduce the retrieval time. This study proposes a strategy of query region determination based on the Region Importance Index (RII) value and relative position of the Saliency Region Overlapping Block (SROB) to produce a more efficient RBIR. The entire region is formed by using the mean shift segmentation method. The RII value is calculated based on a percentage of the region area and region distance to the center of the image. Whereas the target regions are determined by considering the relative position of SROB, the performance of the proposed method is tested on a CorelDB dataset. Experimental results show that the proposed method can reduce the Average of Retrieval Time to 0.054 seconds with a 5x5 block size configuration."

"Every organization today needs a mission statement as the saying goes. Many consider mission statement s as to be important to bunsine success...."

"Time synchronization is a vital process in wireless sensor networks, where energy sources are highly limited. In this work, we propose a broadcast-based skew correction technique that will improve both the accuracy and the lifetime of any time synchronization protocol that only corrects time offsets among sensor nodes. Using time information transmitted periodically by the root node, each client node can compensate its software clock frequency in real time after an initial offset correction. The experimental results show that a clock skew below 0.05 us/s can be consistently achieved with appropriate compensation parameters after the correction process is stabilized."