Test Results of the Long Baseline Navigation Solutions under a Large a Priori Position Uncertainty

A method is proposed for long baseline navigation of autonomous underwater vehicles (AUV) to be used in the case of a large a priori position uncertainty. The new modified method is based on the iterated Kalman filter (IKF) working with different initial linearization points. The final solution is calculated by clustering and weighting the IKF results. This approach allows position estimates to be determined in accordance with the global maximum of posteriori probability density of coordinates. The test results obtained with the use of three beacons and an underwater vehicle are presented.

DIAGNOSIS OF STUDENTS’ ERRORS IN FINDING AREAS BY INTEGRATION

This study aims to diagnose students' errors in finding the area using integration. Errors can be seen from the student completion steps that are not correct. This type of research is qualitative research. The applied instruments were diagnostic tests and interview guidelines. The subjects consisted of Universitas Muhammadiyah Parepare students from Mathematics Education Study Program. Then, the researchers selected three subjects from 23 subjects that committed various errors. The results showed that the errors were: (1) Conceptual error, (a) substitution errors for the lower bound and upper bound, (b) misunderstanding in drawing the graph of a function. (2) Procedural errors dealing with incorrect calculation operation. (3) Final solution errors dealing with incapability to find the accurate answers based on the questions. Therefore, it is necessary to diagnose errors made by students using integration to calculate the area so that for lecturers, it becomes a reference to minimize errors made by students and find solutions for the mistakes made.

Neo-Hobbesianism in the DPRK: A Provisional Theory of Authoritarianism

This article presents an original historical-philosophical conception that attempts to discern the matter, form, and power of the Democratic People’s Republic of Korea (dprk). A panoramic and problematizing cognitive framework, the theory configurates 629 years of sociopolitical history from 1392 to 2021 and then comparatively discusses the dprk system in relation to ancient democracy and liberal democracy from Pericles to Samuel P. Huntington. The article is divided into three parts, which outline the theory and its principles, map historical foundations and political phases, and address social relations, state will, and political reality. Description and analysis convey the thesis that the dprk polity is home to a Neo-Hobbesian formation: a hybrid state entity that is historically modern, politically absolutist, and illiberally democratic, with a transforming cross-civilizational physiognomy. By design, the “soft” theory is conceived to stimulate academic discussion and debate, not declare a final solution.

Forced into Exile and Fighting Back

The Red Guards, backed by the Maoist military representatives stationed in Jack’s office, cajoled Yuan-tsung and Jack into going to the backwater Upper Felicity Village, which was the Red Guards’ final solution to the problem of disposing of the couple. But Yuan-tsung reconnected with Jack’s American brother-in-law, Jay Leyda, who was teaching at York University in Canada. Eventually, with the secret help of a fellow victim Yuan-tsung had met by happenstance on a bus, and despite some letters intercepted by Red Guards, Jack was able to get messages from Leyda. Leyda succeeded in organizing a speech tour for Jack to Canadian and American universities, and informed Zhou Enlai of it. On the prime minister’s personal order, Jack was brought back to Beijing and granted exit visas for the family. After the tour of Chinese cities arranged by Zhou Enlai, Jack, Yuan-tsung, and their son left China in May 1971, two months before Kissinger’s secret visit to China in July.

About the features of the least squares method with linearization when determining nonlinear parameters of functional dependencies

The features of approximation of empirical data by functional dependence with nonlinear parameters using the two-stage least squares method are considered in this paper. A method of simplified parameter estimation by constructing a new expression that depends on the parameters in a linear way is described. To obtain the final solution, the least squares estimation of the main dependence linearized in terms of parameters is performed. The influence of various forms of noise imposed on the theoretical dependence on the approximations is modeled.