San Diego

The San Diego chapter of Papers We Love

Papers We Love has a Code of Conduct. Please contact one of the Meetup's organizers if anyone is not following it. Be good to each other and to the PWL community!

Chapter details

Sign-up: Please RSVP for meetings via Meetup.com

Twitter: @pwl_sd

Organizers:

Sponsors

Chapter Meetups

Dataflow Programming

Map Date/Time: 2019-07-03 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

In dataflow programming, programs are represented as directed graphs (and are often assembled visually); data “flows” through arcs and is processed by nodes.

In this presentation, we’ll compare dataflow against the imperative and functional programming paradigms, and explore the suitability of dataflow for two tasks: big data analysis and DSP.

Presenter: Marvin Humphrey

Video introduction to dataflow programming: https://www.youtube.com/watch?v=iFlT93wakVo

Paper: “Advances in Dataflow Programming Languages”, by Johnston, Hanna, and Millar (2004)

http://www.cs.ucf.edu/~dcm/Teaching/COT4810-Spring2011/Literature/DataFlowProgrammingLanguages.pdf

---

How to read the paper, in four optional steps:

0. Skip it and attend anyway - th…

Read more about this Meetup

Real-time Beat Tracking

Map Date/Time: 2019-06-06 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Getting a computer to "feel the beat" of live music, so that it can clap along or dance or play accompaniment, is devilishly difficult... but why? We'll examine a beat-tracking system which performs comparatively well (but still miserably) for a limited range of pop music inputs — and contemplate what it takes to do better.

Presenter: Marvin Humphrey

Paper: "An Audio-based Real-time Beat Tracking System for Music With or Without Drum-sounds", by Masataka Goto (2001)

http://www-labs.iro.umontreal.ca/~pift6080/H09/documents/papers/goto_jnmr.pdf

Notes:

(Reading the paper is not required — it is expected that many attendees will have at most glanced at the abstract.)

Section 5, "Applications", provides motivation — why solving the beat-tracking problem well is worthwhile. This presentation will focus on adaptive accompaniment: what it ta…

Read more about this Meetup

How to Share a Secret

Map Date/Time: 2019-05-02 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

"How to Share a Secret", by Adi Shamir (1979).

Presented by Nate Gentile.

Abstract: In this paper we show how to divide data D into n pieces in such a way that D is easily reconstructable from any k pieces, but even complete knowledge of k - 1 pieces reveals absolutely no information about D. This technique enables the construction of robust key management schemes for cryptographic systems that can function securely and reliably even when misfortunes destroy half the pieces and security breaches expose all but one of the remaining pieces.

https://cs.jhu.edu/~sdoshi/crypto/papers/shamirturing.pdf

In addition to the main talk by Nate, Marvin Humphrey will present a lightning talk on "When to Share a Secret", discussing Shamir's algorithm in the context of the death of QuadrigaCX CEO Gerald Cotten.

Read more about this Meetup

Identifying Student Misconceptions of Programming

Map Date/Time: 2019-04-04 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Identifying Student Misconceptions of Programming, by Lisa Kaczmarczyk et al. 2010.

Presented by Lisa Kaczmarczyk

We are fortunate to have this paper presented by the first author. In addition, this paper was just awarded "Top Ranked Symposium Paper of All Time" by ACM SIGCSE https://www.acm.org/media-center/2019/march/sigcse-top-10-papers

Abstract: Computing educators are often baffled by the misconceptions that their CS1 students hold. We need to understand these misconceptions more clearly in order to help students form correct conceptions. This paper describes one stage in the development of a concept inventory for Computing Fundamentals: investigation of student misconceptions in a series of core CS1 topics previously identified as both important and difficult. Formal interviews with students revealed four distinct themes, each containing many interesting miscon…

Read more about this Meetup

Lightning Talks

Map Date/Time: 2019-03-07 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Preview List: "Type-level Web APIs with Servant" / "New Directions in Cryptography Section III: Public Key Cryptography" / "Dynamo: Amazon's highly available key-value store" / "Backpage and Bitcoin: Uncovering Human Traffickers"

Detailed List:
_________________________
"Type-level Web APIs with Servant"
Presented by Erik Aker
https://www.andres-loeh.de/Servant/servant-wgp.pdf
_________________________
"New Directions in Cryptography Section III: Public Key Cryptography"
Presented by Mike Mull
https://ee.stanford.edu/~hellman/publications/24.pdf
_________________________
"Dynamo: Amazon's highly available key-value store"
Presented by Marvin Humphrey
http://ww…

Read more about this Meetup

December Social Hour

Map Date/Time: 2018-12-06 07:00pm Location: Stout Public House - 1125 6th Ave, San Diego 92101 92101

It's getting on December,
The holidays are here!
We've feasted and shopped,
and we miss your CS cheer!

Toilsome relatives flocked,
Fattening desserts quite well stocked,
Yet we haven't a speaker,
oh dear!

Please come join us for the PWL December social hour! We will be right down the street from our usual venue, at Stout Public House on sixth avenue, just south of B street!

Street parking on 6th, 7th & 8th Avenues north of B Street is usually easy at that hour. Meters nearby are free after 6. Read signage before you park on A street.

If you're interested in presenting a paper please fill out this form (https://docs.google.com/forms/d/e/1FAIpQLScaI-fWdys27-ByT_HdtsJ73V4AxZr0hf1GSqLsQ1IwAaPdIQ/viewform) or talk to us in person at the meetup.

Read more about this Meetup

The Properties and Promises of UTF-8

Map Date/Time: 2018-11-01 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

"The Properties and Promises of UTF-8", by Martin J. Dürst (1997).

Presented by Marvin Humphrey.

OVERVIEW:

Created by Ken Thompson one night in September 1992 on a placemat in a New Jersey diner, UTF-8 is a spectacular quintuple bank shot of design: optimal across so many criteria that it's hard to believe anybody could pull it off.

Over the years, UTF-8 has increasingly eclipsed all of the alternatives. UTF-1 and UTF-7 are obsolete and only of historical interest; UTF-32 has limited practical utility; UCS-2 can't express all of Unicode... the only serious competitor remaining is UTF-16, but UTF-8 has continued to gain market share.

In 1997, Martin J. Dürst gave a talk at the 11th International Unicode Conference in San Jose on "The Properties and Promises of UTF-8". Two decades later at Papers We Love San Diego, we will review those marvelous properties and contemplate all of the promises that UTF-8 has fulfilled.

DOWNLOAD:

Read more about this Meetup

Differential Privacy

Map Date/Time: 2018-10-04 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

"Differential Privacy", by Cynthia Dwork (2006).

Presented by Mike Mull.

ABSTRACT:

In 1977 Dalenius articulated a desideratum for statistical databases: nothing about an individual should be learnable from the database that cannot be learned without access to the database. We give a general impossibility result showing that a formalization of Dalenius’ goal along the lines of semantic security cannot be achieved. Contrary to intuition, a variant of the result threatens the privacy even of someone not in the database. This state of affairs suggests a new measure, differential privacy, which, intuitively, captures the increased risk to one's privacy incurred by participating in a database. The techniques developed in a sequence of papers [8, 13, 3], culminating in those described in [12], can achieve any desired level of privacy under this measure. In many cases, extremely accurate information about the database can be provided while simultaneously ensuring very h…

Read more about this Meetup

On Data Banks and Privacy Homomorphisms

Map Date/Time: 2018-09-06 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

"On Data Banks and Privacy Homomorphisms", by Rivest, Adleman, and Dertouzos (1978).

Presented by Nate Gentile.

Abstract: Encryption is a well-known technique for preserving the privacy of sensitive information. One of the basic, apparently inherent, limitations of this technique is that an information system working with encrypted data can at most store or retrieve the data for the user; any more complicated operations seem to require that the data be decrypted before being operated on. This limitation follows from the choice of encryption functions used, however, and although there are some truly inherent limitations on what can be accomplished, we shall see that it appears likely that there exist encryption functions which permit encrypted data to be operated on without preliminary decryption of the operands, for many sets of interesting operations. These special encryption functions we call "privacy homomorphisms"...

Read more about this Meetup

A Neural Algorithm of Artistic Style

Map Date/Time: 2018-08-02 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

A Neural Algorithm of Artistic Style
https://arxiv.org/pdf/1508.06576.pdf

Presented by Andrew Carroll
github: https://github.com/antcarro

Abstract:
How would Georges Serat have painted the view at Sunset Cliffs? How would Hokusai have painted the breaks off of La Jolla? What would a hurricane over San Diego look like? Though we can't change history or the climate to visualize these possibilities, a clever algorithm proposed by Gatys, Ecker and Bethge and built atop convolutional neural networks can get us close. "Neural Style Transfer", as it has become known, is a family of techniques that can reimagine a target image in a completely different style, provided by a second image or painting. Recent classics from this collection of techniques include skylines reimagined as though they were the subject of Starry Night, Benedict Cumbe…

Read more about this Meetup

GloVe: Global Vectors for Word Representation

Map Date/Time: 2018-07-05 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

GloVe: Global Vectors for Word Representation
https://nlp.stanford.edu/pubs/glove.pdf

Presented by Michael Jalkio, Data Engineer at Classy
github: https://github.com/mjalkio

Abstract:
Recent methods for learning vector space representations of words have succeeded in capturing fine-grained semantic and syntactic regularities using vector arithmetic, but the origin of these regularities has remained opaque. We analyze and make explicit the model properties needed for such regularities to emerge in word vectors. The result is a new global logbilinear regression model that combines the advantages of the two major model families in the literature: global matrix factorization and local context window methods. Our model efficiently leverages statistical information by training only on the nonzero elements in a word-word cooccurrence m…

Read more about this Meetup

Open Sound Control [1997]

Map Date/Time: 2018-06-07 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

"Open Sound Control: A New Protocol for Communicating with Sound Synthesizers", by Matthew Wright and Adrian Freed [1997]

Presented by Marvin Humphrey, Software Consultant and in a past life, an Audio Mastering Engineer.

Abstract: "Open SoundControl is a new protocol for communication among computers, sound synthesizers, and other multimedia devices that is optimized for modern networking technology. Entities within a system are addressed individually by an open-ended URL-style symbolic naming scheme that includes a powerful pattern matching language to specify multiple recipients of a single message. We provide high resolution time tags and a mechanism for specifying groups of messages whose effects are to occur simultaneously. There is also a mechanism for dynamically querying an Open SoundControl system to find out its capabilities and documentation of its features."

Read more about this Meetup

A Categorical Theory of Patches

Map Date/Time: 2018-05-03 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

A Categorical Theory of Patches
https://arxiv.org/abs/1311.3903

Presented by Ben Sima, a Clojure/Haskell hacker

Abstract:
When working with distant collaborators on the same documents, one often uses a version control system, which is a program tracking the history of files and helping importing modifications brought by others as patches. The implementation of such a system requires to handle lots of situations depending on the operations performed by users on files, and it is thus difficult to ensure that all the corner cases have been correctly addressed. Here, instead of verifying the implementation of such a system, we adopt a complementary approach: we introduce a theoretical model, which is defined abstractly by the universal property that it should satisfy, and work out a concrete description of it. We begin by defining a category of files and patches, where the operation of merging the effe…

Read more about this Meetup

Bitcoin: A Peer-to-Peer Electronic Cash System

Map Date/Time: 2018-04-05 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Bitcoin: A Peer-to-Peer Electronic Cash System by Satoshi Nakamoto
https://bitcoin.org/bitcoin.pdf

Presented by Gabriel Bonner, Software Engineer at Independa

Of course you're aware of Bitcoin, you probably know some other cryptocurrencies and you might even have money in the market. But do you really understand how it works, under the hood? Why is the blockchain protocol considered secure enough that investors have poured billions of dollars into it and whole new industries have sprung up around it? Join us to take a deep dive into a technology that seems poised to revolutionize the financial industry, and perhaps others. Whether you're a blockchain bull, skeptic, cynic, or blockhead we welcome you to learn about this popular topic and participate in a lively discussion after the presentation.

Abstract: A purely peer-to-peer version of electronic cash would allow online payments to be sent dire…

Read more about this Meetup

AlphaGo: Mastering the game of Go with deep neural networks and tree search

Map Date/Time: 2018-03-01 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Mastering the game of Go with deep neural networks and tree search
https://storage.googleapis.com/deepmind-media/alphago/AlphaGoNaturePaper.pdf

Presented by Katie Everett

Paper Abstract:
The game of Go has long been viewed as the most challenging of classic games for artificial intelligence owing to its enormous search space and the difficulty of evaluating board positions and moves. Here we introduce a new approach to computer Go that uses ‘value networks’ to evaluate board positions and ‘policy networks’ to select moves. These deep neural networks are trained by a novel combination of supervised learning from human expert games, and reinforcement learning from games of self-play. Without any lookahead search, the neural networks play Go at the level of state-of-the-art Monte Carlo tree search programs that simulate thousands of random games of self-pla…

Read more about this Meetup

Discussion Group - The Meltdown Paper

Map Date/Time: 2018-02-01 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

-Meltdown-

In what been described as perhaps the worst CPU vulnerability ever, the recently disclosed Meltdown attack affects every Intel x86 processor made within the past 23 years, and also some ARM-based processors. Mitigations for the Meltdown vulnerability have appreciably slowed down servers, consumer computers, and smartphones worldwide, and sparked a massive conversation in the global technology community about a new class of sidechannel attack. Come join the conversation as we host a discussion group on the meltdown paper. https://meltdownattack.com/meltdown.pdf

The discussion group is to be chaired by Daniel Norman. Previous discussion groups we've hosted resulted in fascinating and quite lively conversation. You don't have to read the paper to join the discussion, but it is encouraged that you do so.

Pizza and beverages provided by güdTECH. Street parking on 6th, 7th & 8th Ave…

Read more about this Meetup

Monads for Functional Programming

Map Date/Time: 2018-01-04 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Monads for Functional Programming by Philip Wadler
http://homepages.inf.ed.ac.uk/wadler/papers/marktoberdorf/baastad.pdf

Presented by Erik Aker, Software Engineer at Qualcomm

Computer Scientist Philip Wadler is one of the co-creators of the Haskell programming language, a lazy, pure, Functional Programming language. Being a “pure” language, Haskell was initially only capable of evaluating functions without side effects, which unfortunately ruled out all forms of interacting with the operating system (file IO, user input, user output, etc.). If you’ve ever included a “print” statement in a computer program, then you may be able to imagine the scope of this limitation. In fact, programs that can’t talk to the outside world are typically not very interesting, but Haskell overcame …

Read more about this Meetup

Raft: In Search of an Understandable Consensus Algorithm

Map Date/Time: 2017-11-02 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

In Search of an Understandable Consensus Algorithm (Extended Version)
AKA - The Raft Paper

https://raft.github.io/raft.pdf

Presented by Chris Hiestand, Systems Consultant at Kistek LLC

How does a distributed system maintain a consistent state that is resilient to failures, while keeping that system understandable by the average engineer? Raft is an answer to that problem and is being used by many modern tools including etcd and consul.

As a supplement to the paper, check out these great visualizations:

https://raft.github.io/
http://thesecretlivesofdata.com/raft/

Street par…

Read more about this Meetup

HyperLogLog in Practice: Algorithmic Engineering of a State of The Art...

Map Date/Time: 2017-10-05 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

HyperLogLog in Practice: Algorithmic Engineering of a State of The Art Cardinality Estimation Algorithm
https://static.googleusercontent.com/media/research.google.com/en/us/pubs/archive/40671.pdf

Presented by Mike Mull, Software Engineer

Abstract:

Cardinality estimation has a wide range of applications and is of particular importance in database systems. Various algorithms have been proposed in the past, and the HyperLogLog algorithm is one of them. In this paper, we present a series of improvements to this algorithm that reduce its memory requirements and significantly increase its accuracy for an important range of cardinalities. We have implemented our proposed algorithm for a system at Google and evaluated it empirically, c…

Read more about this Meetup

An Axiomatic Basis for Computer Programming

Map Date/Time: 2017-08-03 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

An Axiomatic Basis for Computer Programming by C.A.R. Hoare
https://github.com/papers-we-love/papers-we-love/blob/master/comp_sci_fundamentals_and_history/axiomatic-basis-computer-programming.pdf

Presented by Valentin Robert (twitter)

Street parking on 6th, 7th & 8th Avenues north of B Street is usually easy at that hour. Meters nearby are free after 6. Read signage before you park on A street. 

If you're interested in presenting a paper please fill out this form or talk to us in per…

Read more about this Meetup

Personal Dynamic Media

Map Date/Time: 2017-07-06 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Xerox PARC in the 1970s was a legendary hothouse of innovation, producing such technological marvels as the laser printer, Ethernet, "object-oriented programming" (as a coherent paradigm)... and the world's first GUI workstation: the Xerox Alto.

The vision which led to the Alto is most fully laid out in the 1977 magazine article "Personal Dynamic Media", which describes the "interim Dynabook", a prototype laptop.  The article captures a moment of rapid evolution in how humans interact with computers, describing nascent forms of many now-ubiquitous GUI applications, anticipating the PC revolution of the 1980s -- and offering insight into what made PARC so special and how we might replicate aspects of the PARC environment today.

Personal Dynamic Media by Alan Kay and Adele Goldberg.

Presented by Marvin Humphrey.

Street parking on 6th, 7th & 8th Avenues north of B Street is usuall…

Read more about this Meetup

Spanner, TrueTime & The CAP Theorem

Map Date/Time: 2017-05-04 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Spanner, TrueTime & The CAP Theorem

https://research.google.com/pubs/pub45855.html

Presented by Daniel Norman

Abstract:
Spanner is Google's highly available global-scale distributed database. It provides strong consistency for all transactions. This combination of availability and consistency over the wide area is generally considered impossible due to the CAP Theorem. We show how Spanner achieves this combination and why it is consistent with CAP. We also explore the role that TrueTime, Google's globally synchronized clock, plays in consistency for reads and especially for snapshots that enable consistent and repeatable analytics.

Street parking on 6th, 7th & 8th Avenues north of B Street is usually easy at that hour. Meters nearby are free after 6. Read signage before you park on A street.

If you're interested in presenting a paper please fill out

Read more about this Meetup

Monoids: Theme and Variations (Functional Pearl)

Map Date/Time: 2017-04-06 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Monoids: Theme and Variations (Functional Pearl)

http://repository.upenn.edu/cis_papers/762/

Presented by Jesse Williamson, Developer of soft wares, Scripter of Javas.

Abstract

The monoid is a humble algebraic structure, at first glance even downright boring. However, there’s much more to monoids than meets the eye. Using examples taken from the diagrams vector graphics framework as a case study, I demonstrate the power and beauty of monoids for library design. The paper begins with an extremely simple model of diagrams and proceeds through a series of incremental variations, all related somehow to the central theme of monoids. Along the way, I illustrate the power of compositional semantics; why you should also pay attention to the monoid’s even humbler cousin, the semigroup; monoid homomorphisms; and monoid actions…

Read more about this Meetup

Discussion Group: As We May Think

Map Date/Time: 2017-03-02 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

As We May Think (html) (pdf) by Vannevar Bush

Presented By Lisa Kaczmarczyk, owner of a business that provides research and evaluation services for the hi-tech industry and academia, and an Adjunct Professor of Computer Science at Harvey Mudd College

Summary via Wikipedia:

"As We May Think" is a 1945 essay by Vannevar Bush which has been described as visionary and influential, anticipating many aspects of information society. It was first published in The Atlantic in July 1945 and republished in an abridged version in September 1945—before and after the atomic bombings of Hiroshima and Nagasaki. Bush expresses his concern for the direction of scientific efforts toward destruction, rather than understan…

Read more about this Meetup

Discussion Group: Reflections on Trusting Trust

Map Date/Time: 2017-01-05 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Reflections on Trusting Trust, Ken Thompson, 1984
https://www.ece.cmu.edu/~ganger/712.fall02/papers/p761-thompson.pdf

Discussion led by Marvin Humphrey, freelance software developer and a Director at the Apache Software Foundation

A selection of discussion questions will be posted in advance of the meetup. Attendees are encouraged to add their own questions.

Street parking on 6th, 7th & 8th Avenues north of B Street is usually easy at that hour. Meters nearby are free after 6. Read signage before you park on A street. 

If you're interested in presenting a paper please fill out this form or talk to us in person at the meetup. 

Read more about this Meetup

On the Criteria To Be Used in Decomposing Systems into Modules

Map Date/Time: 2016-12-01 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

On the Criteria To Be Used in Decomposing Systems into Modules 
https://www.cs.umd.edu/class/spring2003/cmsc838p/Design/criteria.pdf

Presented by Chris Hiestand, Software Engineer at Zesty.io

Street parking on 6th, 7th & 8th Avenues north of B Street is usually easy at that hour. Meters nearby are free after 6. Read signage before you park on A street. 

If you're interested in presenting a paper please fill out this form or talk to us in person at the meetup. 

Read more about this Meetup

On the Resemblance and Containment of Documents

Map Date/Time: 2016-11-03 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

On the Resemblance and Containment of Documents
http://www.cs.princeton.edu/courses/archive/spr05/cos598E/bib/broder97resemblance.pdf

Presented by Mike Mull, Software Engineer at Intensity Corp.

Street parking on 6th, 7th & 8th Avenues north of B Street is usually easy at that hour. Meters nearby are free after 6. Read signage before you park on A street. 

If you're interested in presenting a paper please let us know by adding a comment or contacting us via email or on twitter, or talk to us in person at the meetup. 

Read more about this Meetup

Chord: A Scalable Peer-to-peer Lookup Protocol for Internet Applications

Map Date/Time: 2016-10-06 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

Presented by Yuri Gorokhov, Software Engineer at MindTouch

Chord: A Scalable Peer-to-peer Lookup Protocol for Internet Applications
https://pdos.csail.mit.edu/papers/ton:chord/paper-ton.pdf

Street parking on 6th, 7th & 8th Avenues north of B Street is usually easy at that hour. Meters nearby are free after 6. Read signage before you park on A street. 

If you're interested in presenting a paper please let us know by adding a comment or contacting us via email or on twitter, or talk to us in person at the meetup. 

Read more about this Meetup

PWLSD First Meetup - A Critique of CAP Theorem

Map Date/Time: 2016-08-04 07:00pm Location: güdTECH Offices - 600 B Street, Ste 2120, San Diego

A Critique of the CAP Theorem by Martin Kleppmann
https://arxiv.org/abs/1509.05393

Presented by Daniel Norman

Street parking on 6th, 7th & 8th Avenues north of B Street is usually easy at that hour. Meters are free after 6. Read signage before you park on A street. 

If you're interested in presenting a paper please let us know by adding a comment or contacting us via email or on twitter, or talk to us in person at the meetup.

Read more about this Meetup