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In facing global business competition, it is necessary to improve performance and competitiveness not only through products quality and cost efficiency, but also the use of Intellectual Capital, which includes Human Capital, Structure Capital, and Relational Capital. Similar to companies in general, the implementation of Intellectual Capital will also have an impact on MSMEs. The object of this research is the UMKM owned by the Difabel Community in Klaten. The test results show that all Intellectual Capital variables consisting of Human Capital, Structure Capital, and Relational Capital have a significant effect on the performance of MSMEs.

In industrial processing, side products are produced in the form of liquid waste containing heavy metals, including Cr (III) which can have a negative impact on the environment. Some egg shell characteristics containing  high concentrations of CaCO3 and have a natural pore structure can be used as adsorbers (biosorbents) of heavy metals produced by the processing industry. The purpose of this study was to obtain the optimum conditions of absorption (adsorption) of Cr (III) metals carried out by egg shell biosorbents. The research method was carried out experimentally which included the preparation of egg shell waste biosorbents, determining the optimum time, as much as 1.0 gram of eggshell biorsorbent was put into 25 ml of heavy metal waste solution with a concentration of 50 ppm, then adsorption was carried out with time variations of 5, 10, 20 , 30, 40, 50, 60 and 120 minutes. Variation of  Cr concentration  were 50,0 ppm; 100,0 ppm,  150,0 ppm; 200,0 ppm; 250,0 ppm; 300,0 ppm; 350,0 ppm, 400,0 ppm; 450,0 ppm; 500,0 ppm; dan 1000 ppm. After that the mixture is filtered and the filtrate is read on the Atomic Absorption Spectrophotometer (AAS) to find out the maximum adsorption. The results showed the optimum conditions of adsorption of Cr (III) metals obtained an optimum time of 40 minutes with an absorption capacity of 1242.46 µg Cr (III) / g biosorbent, and optimum concentration with optimum treatment time and weight at 200 ppm with an absorption capacity of 4984 , 99 µg Cr (III)/g biosorbent. The adsorption isotherm adopts the Freundlich isotherm or physically (physical) type, because the linearity of the Freundlich isotherm obtained from the calculation results is R2 = 0.7312 or 73.12% higher than the Langmuir isotherm ie R2 = 0.0335 or 3.35%.  Keyword : Cr (III) heavy metal, eggshell biosorbent, optimum adsorption conditions

BLDC motor applications used in various forms in instrumentation, robotics, household, and transportation. One application of transportation equipment used as a propeller of electric bicycle vehicles. The value of the bicycle vehicle adjusted to the speed set, the amount that has determined. The purpose used in this study is to improve the efficiency of the regulation of BLDC motors on electric bicycles. Indicators of increasing performance are increasingly steady-state errors, and transient response required. The method used in this research is to do mathematical modeling in the form of transfer and optimization function equations. The model used is the model with the structure of the transfer function, while the optimization method used in this study is the Ziegler-Nichols method and firefly algorithm. The firefly algorithm is used in this study to obtain optimal Kp, Ki, and Kd values. The results showed that the firefly algorithm achieved better performance compared to the Ziegler-Nichols method.

Measurement of firm performance becomes very important for management to evaluate and planning for future goals. Several factors can affect firm performance, including profitability, ownership structure, and company size. For that this study aims to examine the effect of profitability, ownership structure, company size on firm performance with capital structure as an intervening variable. Data obtained during the period 2016-2018 from manufacturing companies listed on the Indonesia Stock Exchange. The results in this study indicate profitability, ownership structure and firm size simultaneously (together) affect the capital structure. Profitability, ownership structure, firm size, and capital structure simultaneously (together) affect the firm's performance.