### Seminare

## Alternative Optimization Methods for Training of Neural Networks

#### Beschreibung

To this day, the go to algorithms for training neural netowrks are stochastic gradient descent or some flavour of the Adam family. Other algorithms, such as quasi-Newton or derivative free methods are less requently used, although they can, under certain circumstances, bring better results. The goal of this work is to write a survey on the usage of alternative methods for taining, such as quasi-Newton or derivative free algorithms.

#### Voraussetzungen

Knowledge in optimization and basic linear algebra is recommended.

#### Kontakt

markus.leibl@tum.de

#### Betreuer:

## A polynomial time optimal diode insertion/routing algorithm for fixing antenna problem

#### Beschreibung

Abstract— Antenna problem is a phenomenon of plasma induced gate oxide degradation. It directly affects manufacturability of VLSI circuits, especially in deep-submicron technology using high density plasma. Diode insertion is a very effective way to solve this problem Ideally diodes are inserted directly under the wires that violate antenna rules. But in today's high-density VLSI layouts, there is simply not enough room for "under-the-wire" diode insertion for all wires. Thus it is necessary to insert many diodes at legal "off-wire" locations and extend the antenna-rule violating wires to connect to their respective diodes. Previously only simple heuristic algorithms were available for this diode insertion and routing problem. In this paper we show that the diode insertion and routing problem for an arbitrary given number of routing layers can be optimally solved in polynomial time. Our algorithm guarantees to find a feasible diode insertion and routing solution whenever one exists. Moreover we can guarantee to find a feasible solution to minimize a cost function of the form /spl alpha/ /spl middot/ L + /spl beta/ /spl middot/ N where L is the total length of extension wires and N is the total number of Was on the extension wires. Experimental results show that our algorithm is very efficient.

#### Kontakt

alex.truppel@tum.de

#### Betreuer:

## A general multi-layer area router

#### Beschreibung

Abstract— This paper presents a general multi-layer area router based on a novel grid construction scheme. The grid construction scheme produces more wiring tracks than the normal uniform grid scheme and accounts for differing design rules of the layers involved. Initial routing performed on the varying capacity grid is followed by a layer assignment stage. Routing completion is ensured by iterating local and global modifications in the layer assignment stage. Our router has been incorporated into the Custom Cell Synthesis project at MCC and has shown improved results for cell synthesis problems when compared with the router Mighty which was used in earlier versions of the project.

#### Kontakt

alex.truppel@tum.de