The purpose of this study was to determine the results of the development of an electronic module on multiple integral materials and students' perceptions of the product being developed. The type of ...research conducted is R&D research with the chosen development model being the 4-D development model. The research sample used was two expert lecturers as product assessors and 25 students as samples whose perceptions were measured. The sampling technique used was purposive sampling with the instruments used were student needs questionnaires, material validation, media validation, and student perceptions. Data analysis for the questionnaire is descriptive statistics, while for instrument validation data using reliability and validity tests. The results of the data obtained indicate that the product is feasible to use and can be accessed using a mobile phone via the link provided by the author, while the perception of the electronic module obtained shows a very good perception. Thus, this module is considered feasible and ready to be used to assist students in understanding the multiple integral materials.
This research aims to determine prospective mathematics teacher students' learning obstacles and knowledge acquisition process on the concept of fold integrals and their applications. In the ...acquisition process, students extract, structure, and organize knowledge both obtained from reading results and information received during the learning process in class; this is studied comprehensively. This research is Didactical Design Research. The research participants were 46 fourth-semester students in a study program producing prospective mathematics teachers. Research data comes from tests, observations, interviews, and documentation. The stages of data analysis are identification, clarification, reduction, and verification, which are then presented in a narrative descriptive manner. This research is essential because apart from identifying learning obstacles, various types of learning obstacles and the process of knowledge acquisition on related concepts and their multiple causes are also analyzed. The results obtained were (1) Students experienced ontogenic learning obstacles of psychological, instrumental, and conceptual types in the fold integral concept; apart from that, epistemological learning obstacles were also identified; (2) the process of acquiring knowledge related to the concept of double and triple integrals and their applications is not yet running perfectly, hampered by prerequisite knowledge, lack of technical ability, weak mastery of concepts, and limited understanding related to student habits. Further studies need to be carried out regarding the diffusion process by lecturers to facilitate the knowledge acquisition process so that students can construct the fold integral concept well. Penelitian ini bertujuan mengetahui hambatan belajar dan proses akuisisi pengetahuan mahasiswa calon guru matematika pada konsep integral lipat beserta aplikasinya. Pada proses akuisisi, mahasiswa melakukan ekstraksi, strukturisasi, dan pengorganisasian pengetahuan baik yang diperoleh dari hasil baca maupun informasi yang diterima selama proses belajar di kelas, hal ini dikaji secara kpmprehensif. Penelitian ini merupakan penelitian Didactical Design Research. Partisipan penelitian sebanyak 46 mahasiswa semester empat pada program studi penghasil calon guru matematika. Data penelitian berasal dari tes, observasi, wawancara, dan dokumentasi. Tahapan analisis data yaitu identifikasi, klarifikasi, reduksi, dan verifikasi, yang kemudian disajikan secara deskriptif naratif. Penelitian ini penting dilakukan, karena selain diidentifikasi hambatan belajar, juga dianalisa berbagai tipe hambatan belajar beserta proses akuisisi pengetahuan pada konsep terkait beserta berbagai penyebanya. Hasil yang diperoleh adalah (1) Mahasiswa mengalami hambatan belajar ontogenik tipe psikologis, instrumental, dan konseptual pada konsep integral lipat, selain itu teridentifikasi juga hambatan belajar epistemologis; (2) proses akuisisi pengetahuan terkait konsep integral lipat dua dan lipat tiga beserta aplikasinya belum berjalan sempurna, terkendala oleh pengetahuan prasyarat, kurangnya kemampuan teknis, lemahnya penguasaan konsep, dan terbatasnya pemahaman terkait dengan kebiasaan mahasiswa. Perlu dilakukan kajian lebih lanjut terkait proses difusi yang dilakukan dosen untuk memfasilitasi proses akuisisi pengetahuan, sehingga mahasiswa dapat mengkonstruksi konsep integral lipat dengan baik.
Probabilistic load flow (PLF) is a powerful and widely used tool to address the random nature of renewable energy resources for the planning and operation of power systems. In this study, a new ...approach using a combination of the multiple integral method (MIM) and the cumulant method (CM) is proposed for PLF studies. The PLF problem with high dimensionality is decomposed into a bi-level problem and solved by MIM and CM to reduce the computational burden significantly while achieving satisfactory accuracy. The proposed method is applied to the IEEE 118-bus system and is compared with CM and point estimate method. Simulation results show that the proposed method achieves great computational efficiency and accuracy.
In this paper, a generalized differentiation–integration observer is presented based on sensors selection. The proposed differentiation–integration observer can estimate the multiple integrals and ...high-order derivatives of a signal, synchronously. The parameters selection rules are presented for the differentiation–integration observer. The theoretical results are confirmed by the frequency–domain analysis. The effectiveness of the proposed observer is verified through the numerical simulations on a quadrotor aircraft: i) through the differentiation–integration observer, the attitude angle and the uncertainties in attitude dynamics are estimated synchronously from the measurements of angular velocity; ii) a control law is designed based on the observers to drive the aircraft to track a reference trajectory.
We consider the sums
S
(
k
)
=
∑
n
=
0
∞
(
−
1
)
n
k
(
2
n
+
1
)
k
and
ζ
(
2
k
)
=
∑
n
=
1
∞
1
n
2
k
with 𝑘 being a positive integer. We evaluate these sums with multiple integration, a modern ...technique. First, we start with three different double integrals that have been previously used in the literature to show 𝑆(2) = π2/8, which implies Euler's identity ζ(2) = π2/6. Then, we generalize each integral in order to find the considered sums. The 𝑘 dimensional analogue of the first integral is the density function of the quotient of 𝑘 independent, nonnegative Cauchy random variables. In see king this function, we encounter a special logarithmic integral that we can directly relate to 𝑆(𝑘). The 𝑘 dimensional analogue of the second integral, upon a change of variables, is the volume of a convex polytope, which can be expressed as a probability involving certain pairwise sums of 𝑘 independent uniform random variables. We use combinatorial arguments to find the volume, which in turn gives new closed formulas for 𝑆(𝑘) and ζ(2𝑘). The 𝑘 dimensional analogue of the last integral, upon another change of variables, is an integral of the joint density function of 𝑘 Cauchy random variables over a hyperbolic polytope. This integral can be expressed as a probability involving certain pairwise products of these random variables, and it is equal to the probability from the second generalization. Thus, we specifically highlight the similarities in the combinatorial arguments between the second and third generalizations.