Petra Christian University

About: Petra Christian University is a education organization based out in Surabaya, Indonesia. It is known for research contribution in the topics: Population & Customer satisfaction. The organization has 2412 authors who have published 2893 publications receiving 10429 citations.

Pengujian model regresi untuk pengukuran produktivitas tenaga kerja: kasus industri kecil di jawa tengah

Abstract: Managers of small industries need accurate information regarding the type of workers which are most productive. This information can be obtained through regression analysis only if the regression model which is used is correct. This analysis has the objective of determining the proper regression model among four possibilities, including the linear model, quadratic model, square root model and logarithmic model. In addition, another objective is to determine the impact of several influential variables on labor productivity. Although the linear model is often used in productivity research, this analysis shows that for the data used in this study, the quadratic model is the best regression model to be used. It can be concluded that for managers of small businesses: 1) work experience does not make a difference but that age has a negative and significant relationship with productivity; 2) the level of education is significant, though the effect is unclear; 3) educational level may not be ignored but is less important than worker age; 4) it seems that younger workers have higher productivity according to this analysis, perhaps due to greater enthusiasm or an ability to work harder. Abstract in Bahasa Indonesia : Para manajer usaha kecil memerlukan informasi yang tepat mengenai jenis pekerja yang paling produktif. Informasi yang tepat itu dapat diperoleh dari analisis regresi jika dan hanya jika model regresi yang digunakan menjadi tepat. Analisis ini bertujuan untuk menentukan model regresi yang paling tepat dari empat kemungkinan yaitu, model linear, model kuadrat, model akar serta model logarithmic. Selain itu, ada tujuan menentukan pengaruh dari beberapa faktor yang berpengaruh terhadap produktivitas tenaga kerja di industri kecil. Walaupun model linear sering digunakan dalam penelitian produktivitas, analisis ini membuktikan bahwa untuk data yang digunakan dalam analisis ini, model kuadrat menjadi model regresi yang paling tepat untuk digunakan. Kesimpulan untuk para manajer industri kecil adalah bahwa 1) pengalaman kerja tidak berpengaruh tetapi umur mempunyai hubungan yang negatif dan signifikan dengan produktivitas; 2) pendidikan mempunyai pengaruh yang signifikan walaupun hubungannya kurang jelas; 3) tingkat pendidikan tidak dapat diabaikan tetapi menjadi kurang penting dibandingkan dengan umur; 4) orang yang lebih muda menjadi lebih produktif dalam analisis ini, mungkin karena mereka lebih semangat atau dapat bekerja lebih keras. Kata kunci : produktivitas, industri kecil, pengujian model regresi

Komposisi dalam fotografi

Abstract: At the first time%2C Frederick Scott Archer found collodion%2C an element of photography%2C that covered the glasses and can be put it on obscura camera to have the picture. This methode has used before%2C in all European and American countries. The photographer%2C at that time%2C had not cared about the quality of the picture. Meanwhile together advanced technology%2C human discovered some elements that can make a picture became more sharply. From that point%2C photographers become more appreciate with photography work. All sorts of aspects that can give more value for the picture%2C has been more attractived%2C ie: composition that can help to discover a better quality of photography work. Abstract in Bahasa Indonesia : Pada mulanya Frederick Scott Archer menemukan collodion%2C bahan baku fotografi%2C yang dilapiskan ke kaca dan langsung dipasang pada kamera obscura untuk menghasilkan gambar. Cara ini digunakan untuk memotret di seluruh Eropa dan Amerika. Para fotografer pada zaman itu masih belum memperhatikan kualitas gambar. Namun%2C seiring dengan perkembangan zaman dan kecanggihan teknologi%2C manusia menemukan bahan yang dapat membuat sebuah gambar menjadi tajam%2C dan penggemar fotografi pun mulai memperhatikan nilai lebih karya fotografi. Berbagai aspek penunjang keberhasilan yang memberikan nilai lebih mulai diperhatikan%2C antara lain komposisi yang dapat membantu terwujudnya suatu karya fotografi yang bermutu. photography%2C composition

Performance Evaluation of MMA7260QT and ADXL345 on Self Balancing Robot

Abstract: A self balancing robot (SBR) controller needs to detect platform inclination. For this purpose, an accelerometer is used. From various types of accelerometer, we can divide into digital and analog ones. The problem is how to select the right type for the SBR. This paper evaluates the performance of the ADXL345, 3-axis digital output accelerometer and the MMA7260QT, 3-axis analog output accelerometer. The Arduino is used to read data from the sensor and send it to PC for plotting. Both sensors use the lowest sensitivity. The sensors are evaluated with three criteria, i.e. stationary, dynamical response and collaborating with ITG3200 3-axis gyroscope for Kalman filter fusion. For stationary criterion, the ADXL345 is better than the other sensor for all stationary position. For dynamical response, both sensors suffer from the noise due to acceleration of the platform. The sensors do not only sense the gravity but also the acceleration of the platform when it is moved. But the noise level for the ADXL345 is lower than the other. Using Kalman filter makes both sensors show good performance for a SBR application. If three criteria are combined with hardware aspect, then the authors recommend using the ADXL345. Besides, it has several useful features to handle abrupt acceleration.

Study of the Discrete Shear Gap Technique in Timoshenko Beam Elements

Abstract: A major difficulty in formulating a finite element for shear-deformable beams, plates, and shells is the shear locking phenomenon. A recently proposed general technique to overcome this difficulty is the discrete shear gap (DSG) technique. In this study, the DSG technique was applied to the linear, quadratic, and cubic Timoshenko beam elements. With this technique, the displacement-based shear strain field was replaced with a substitute shear strain field obtained from the derivative of the interpolated shear gap. A series of numerical tests were conducted to assess the elements performance. The results showed that the DSG technique works perfectly to eliminate the shear locking. The resulting deflection, rotation, bending moment, and shear force distributions were very accurate and converged optimally to the corresponding analytical solutions. Thus the beam elements with the DSG technique are better alternatives than those with the classical selective-reduced integration.

A proposal of data quality for data warehouses environment

Abstract: The quality of the data provided is critical to the success of data warehousing initiatives. There is strong evidence that many organisations have significant data quality problems, and that these have substantial social and economic impacts. This paper describes a study which explores modeling of the dynamic parts of the data warehouse. This metamodel enables data warehouse management, design and evolution based on a high level conceptual perspective, which can be linked to the actual structural and physical aspects of the data warehouse architecture. Moreover, this metamodel is capable of modeling complex activities, their interrelationships, the relationship of activities with data sources and execution details.