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Running Time: 99 minutes
Released: 03/2014
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The Government plans to impose fines upto Rs.100 million for vessels poaching in Sri Lankan waters and proposals have also been received to increase it up to Rs 175 million.
The Foreign Fisheries Vessels Act to be presented in Parliament this year will solve the issue of poaching by Indian trawlers in Sri Lankan waters, Fisheries and Aquatic Resources Minister Mahinda Amaraweera said.
"Around 80 percent of the drafting process of the Foreign Fisheries Vessels Act has been completed and it will be presented to Parliament this year, Amaraweera said.
The minister said the new Act,fines will be imposed on the vessel owner who will have to appear in courts to secure the release of the vessel. Foreign fishermen involved in poaching in Sri Lankan territorial waters are now charged under the Immigration Act for unlawfully entering the country.
According to Indian media, Rameshwaram fishermen had been protesting against the Sri Lankan government amending its Fisheries and Aquatic Resources Act to ban bottom trawling in the territorial waters of the country, said the Minister.
Amaraweera said the Fisheries Act was amended to strengthen the International Fisheries Law and also to protect the marine resources of the country by adding that all these decisions have been taken for the benefit of Sri Lankan fishermen and not for the fishermen in other countries.
The Minister said the central government of India has realised the damage caused damage caused by bottom trawling to Sri Lanka's marine resources and they have already taken various progressive decisions to solve the issue.
"Appreciating the support extended by the Indian Government, we have agreed to consider India's request to release 42 captured Indian fishing boats in the near future." he added.
A British legislator has said he will continue to push for pressure on Sri Lanka on the human rights issue.
Newly elected as the Chair of the All Party Parliamentary Group for Tamils (APPG), Paul Scully has said human rights concerns remain in Sri Lanka and he pledged to continue to raise the issue internationally.
Scully said he would support the interests of the Tamil community in the UK while the APPG will continue to raise the issue in the UK Parliament, in Brussels and Geneva aiming to keep this in the mind of the Government, the EU and the United Nations.
The main suspect in the shooting at Nallur in Jaffna on Saturday, where Jaffna High Court Judge M. Ilancheliyan and his security detail were shot at killing a police sergeant, surrendered to police short while ago.
Police spokesman SP Ruwan Gunasekara said 39-year-old Selvarasa Jayandan was arrested after he surrendered to the Jaffna Police Station this morning.
Six Special Task Force (STF) officers were hospitalized and a 17 year old youth drowned when a tense situation erupted during a raid conducted in Karadiyanaru, Batticaloa last evening.
Police said the STF personnel from the Maha Oya camp had raided an illegal sand mining operation at the Mundeniyaru lagoon following a tip off.
The Cabinet today approved the proposal to lease out the Hambantota Port to China Merchants Company, Ports and Shipping Minister Mahinda Samarasinghe said.
Earlier, it was reported that two separate companies would be formed to deal with administrative and commercial operations of the port.
The majority equity of the company to be formed for administrative operations would be vested with the Sri Lankan side, he said.
However, the Chinese company would possess majority equity in the company proposed for commercial operations of the Port.
Sri Lanka's Leader of Opposition and the main Tamil party, Tamil National Alliance (TNA) R. Sampanthan has asked the President Maithripala Sirisena to outline a program to address the 'Missing Persons Issue' in a 'meaningful and purposeful way'.
In a letter to the President, the Opposition Leader pointed out that the Government has an obligation to the families of the missing persons to enable them to bring an end to their suffering.
The letter has also been sent to the Prime Minister Ranil Wickremesinghe.
The Megapolis and Western Development Ministry announced that it had submitted a proposal to the government to build an airport within the Colombo Port premises.
The ministry believes that if this project becomes a reality, it would be the strongest port in the region.
Minister Champika Ranawaka said if the proposal is implemented within the next 10 years, the people would capable to airlift from the Colombo Fort without going to Bandaranaike International Airport (BIA).
Protests were staged in the North today over the shooting incident targeting a prominent judge while events were also held in remembrance of the policeman killed in the incident.
Judges, Magistrates and lawyers in the North including Vavuniya and Mannar staged protests over the attack on High Court Judge M. Illanchelian.
Canadian Prime Minister, Justin Trudeau today reiterated the need for accountability in Sri Lanka. He said this in a message to mark the anniversary of Black July.
Jaffna Police have arrested two suspects in connection with Saturday's shooting at the Jaffna High Court judge M. Illancheliyan and his security officers in Nallur.
The two suspects arrested are the brother and a relative of the main suspect, who is still at large. The two suspects are being interrogated in length to find the whereabouts of the main suspect, police said.
The police teams investigating the shooting in which, a police sergeant was killed, suspects the gunman is a former LTTE cadre, the police said.
President Maithripala Sirisena today ordered the security of judges to be strengthened following the Jaffna shooting incident.
He condemned the attack aimed at High Court Judge M. Illanchelian yesterday in Nallur. He also expressed his condolence over the death of police Sergeant Sarath Premachandra during this shooting incident.
The President who paid his attention over the security of judges, directed the Inspector General of Police (IGP) to initiate a special program to strengthen the security of judges.
Former President Mahinda Rajapaksa yesterday urged the government not to take the killing of a police sergeant and wounding a constable at Nallur, Jaffna lightly.
The two policemen were providing protection to Jaffna High Court Judge M Illancheliyan, the former President said that the incumbent government had no regard for the safety and welfare of security forces and police personnel.
"The shooting incident should not be considered lightly", he told The Island, adding that the government should take immediate action to prevent the recurrence of similar incidents.
Defence State Minister Ruwan Wijewardene yesterday strongly refuted claims made by United Nations Special Rapporteur on Human Rights and Counter-terrorism Ben Emmerson that the military was maintaining torture-chambers.
Wijewardene said the government does not agree with the alleged comments made by Ben Emmerson with regards to the above subject, following his visit to Sri Lanka with several other UN Rapporteurs. Wijewardene vehemently refuted that Sri Lanka military was keeping torture-chambers at present and added that the government has a zero-tolerance policy on torture.
A Police Sergeant attached to the security detail of Jaffna High Court Judge M. Ilanchezhiyan, who was undergoing treatment at the Jaffna General Hospital for gunshot injuries in yesterday's shootout at Nallur, died early this morning, the Police said.
They said another Policeman was also injured in the shooting.
An emotional Jaffna High Court Judge Manikkavasagaar Ilanchezhiyan was seen bowing to the wife of the killed Police Sergeant following the postmortem in Jaffna this morning.
The Police Sergeant was killed due to gunshot injuries while giving escort to the Judge Ilanchezhiyan at Nallur.
High Court Judge was seen even more emotional when the wife of Police Sergeant Sarath Premachandra arrived at the scene.
All the persons responsible for the attack on Jaffna High Court Judge Ilanchezhiyan should be immediately arrested, the Tamil National Alliance said yesterday.
In a statement the TNA yesterday condemned the attack on Jaffna High Court Judge Ilanchezhiyan and urged IGP Pujith Jayasundara to investigate the incident promptly.
Two suspects had been arrested by the Police in connection with the shooting incident in which a gunman opened fire at Jaffna High Court Judge M. Ilanchezhiyan and his security detail at Nallur in Jaffna on Saturday, killing a police sergeant.
Police Spokesman SP Ruwan Gunasekara said according to the initial investigation, it was revealed that the shooting was unexpected incident but not a pre-planned attacked.
The United Nations (UN) noted that Sri Lanka has not made enough progress on addressing human rights issues and the issue on missing persons was a concern.
UN Deputy Spokesman Farhan Haq told reporters in New York that during his recent visit to Sri Lanka Jeffrey Feltman, UN Under-Secretary-General for Political Affairs, had also discussed the matter with the Government.
The National Elections Commission announced yesterday that nominations for the North-Central, Eastern and Sabaragamuwa Provincial Councils will be called on 2 October 2017.
Deputy Elections Commissioner M.M. Mohammed said the terms of the North Central, Eastern and Sabaragamuwa Provincial Councils would end on 26 September 2017.
A Tamil National Alliance delegation led by R. Sampanthan yesterday complained to visiting UN Under Secretary General for Political Affairs Jeffery Feltman about a series of issues they had with the state at the world body's office in Colombo.
The UK Foreign and Commonwealth Office's annual human rights report recognises and welcomes improvements in the human rights situation in Sri Lanka, while also emphasising the need for further progress.
The Foreign and Commonwealth Office's (FCO) made public its annual Human Rights Report for 2016 on Thursday (July 20).
Sri Lanka is one of 30 'Human Rights Priority Countries' (HRPCs), countries with which the UK looks for positive engagement that contributes to addressing human rights concerns, the British High Commission said.

subset: commoncrawl


text:
- TheGridMonster
- 3 years ago
Hi Bees,
My fingers swell like there's no tomorrow and now that I'm going to be looking at my hands (and other people will be looking at them) more often, it's really been bugging me. Any tips on how to minimize the swelling that goes on? I don't want to size up my ring because when my fingers are "normal" the ring would be too loose, but when my fingers start swelling, I end up with a muffin top that I hate. I've already been trying to avoid salty foods and drink lots of water, but is there anytihng else I can do?
Thank you!


text:
Team, Inc. (TISI) Cut to "Sell" at ValuEngine
Team, Inc. (NYSE:TISI) was downgraded by analysts at ValuEngine from a "hold" rating to a "sell" rating in a report released on Friday.
Separately, Zacks Investment Research raised Team from a "strong sell" rating to a "hold" rating in a report on Wednesday, May 10th.
Team (NYSE TISI) traded up 1.35% during mid-day trading on Friday, reaching $26.25. 243,976 shares of the company were exchanged. The stock has a 50-day moving average of $26.21 and a 200 day moving average of $31.09. The firm's market capitalization is $782.62 million. Team has a 1-year low of $23.53 and a 1-year high of $39.70.
Team (NYSE:TISI) last announced its quarterly earnings results on Tuesday, May 9th. The business services provider reported ($0.24) earnings per share (EPS) for the quarter. The business had revenue of $286.55 million during the quarter, compared to analyst estimates of $303.30 million. Team had a net margin of 0.71% and a return on equity of 4.98%. Equities research analysts forecast that Team will post $0.53 earnings per share for the current year.
ILLEGAL ACTIVITY NOTICE: "Team, Inc. (TISI) Cut to "Sell" at ValuEngine" was first reported by American Banking News and is the property of of American Banking News. If you are accessing this piece of content on another site, it was illegally stolen and reposted in violation of United States & international trademark & copyright legislation. The original version of this piece of content can be read at https://www.americanbankingnews.com/2017/06/02/team-inc-tisi-cut-to-sell-at-valuengine.html.
Institutional investors have recently made changes to their positions in the stock. UBS Group AG increased its position in shares of Team by 21.6% in the first quarter. UBS Group AG now owns 5,642 shares of the business services provider's stock worth $152,000 after buying an additional 1,003 shares during the period. Mason Street Advisors LLC increased its position in shares of Team by 7.0% in the first quarter. Mason Street Advisors LLC now owns 6,897 shares of the business services provider's stock worth $187,000 after buying an additional 452 shares during the period. Strs Ohio acquired a new position in shares of Team during the first quarter worth about $229,000. Blair William & Co. IL acquired a new position in shares of Team during the first quarter worth about $245,000. Finally, Pitcairn Co. increased its position in shares of Team by 75.9% in the first quarter. Pitcairn Co. now owns 11,482 shares of the business services provider's stock worth $310,000 after buying an additional 4,953 shares during the period. 97.74% of the stock is owned by hedge funds and other institutional investors.
Team Company Profile
Team, Inc is a provider of specialty industrial services, including inspection and assessment, required in maintaining high temperature and high pressure piping systems and vessels. The Company conducts its operations through three segments: Inspection and Heat Treating Services (IHT) Group, Mechanical Services (MS) Group and Quest Integrity (Quest Integrity) Group.
To view ValuEngine's full report, visit ValuEngine's official website.
Receive News & Ratings for Team Inc. Daily - Enter your email address below to receive a concise daily summary of the latest news and analysts' ratings for Team Inc. and related companies with MarketBeat.com's FREE daily email newsletter.


text:
The woven handles on this basket truly make the shape, and give it so much character.
Each one has been hand woven tightly with date palm leaf. It will look great on your kitchen counter holding the latest bounty from the garden, or as a catchall by the front door for keys, spare change, etc.
Handmade in Bangladesh for Fair Wages
- Woven date palm leaf
- Integrated woven handles
- 14L x 11W x 5H inches
- Made in Bangladesh
TEOT is proud to partner with vendors that demonstrate a 100% commitment to Fair Trade in all business activities.
When you purchase this product, you can rest assured that the maker was paid a fair wage by the standards of the developed country where it was purchased. These ideals are rooted in the pursuit of greater justice in world trade.
Shop the entire Fair Trade collection here.


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The Magic Spoon
You know the simple things in life that make life much more convenient, this must be one of them. The genius behind this simple yet very handy design is Ivan Erkic. It can possibly become very popular in Kuwait since most people love tea and consider it part of tradition. This design also won 2010's kitchen tools event, which is all about kitchen innovation.


text:
Quick Details
- Brand Name: BlueXtel
- Model Number: SP084
- Type: Active
- Use: Computer, Home Theatre, Karaoke Player, Mobile Phone, Portable Audio Player, Stage
- Channels: 2 (2.0)
- Special Feature: Portable, Wireless
- Place of Origin: Guangdong, China (Mainland)
- Name: Bluetooth speaker
- Bluetooth Version: V4.0
- Chip Solution: CSR8615
- Operation Frequency: 2.402-2.48GHz
- Play Time: Up to 10 hours
- Talk Time: Up to 12 hours
- Standby Time: Up to 800 hours
- Rated Power: 3W+3W
- Charge Time: <3 hours (approx)
- Operation Range: 10 meters
Packaging & Delivery
|Packaging Details:
|Plastic box
|Delivery Detail:
|Shipped in 7 days after payment
Portable Waterproof Mini Bluetooth Stereo Speaker
-IPX67 waterproof design
-Floating design
-High quality assurance
-3WX2 power
-Super Long Play
-High-quality call results
-AUX IN input support
Product Show:
Charging:In order to charge your speaker's internal battery, connect one end of the included USB cable to the charging port on your speaker. Connect the other to a USB port or AC charging adapter. The LED Light indicator turns red when take up to 3 hours.
-Press and hold the Power button for around 2s. Your speaker will enter pairing mode with voice note "powering on",the red and blue LED lights will flash alternately.
-Go to the Bluetooth Manager of your Bluetooth device. Search Bluetooth devices and select "WINSTONE" to start connecting.
-If required, enter the PIN code "0000" and confirm the entry. Once paired, you will hear your speaker audibly say: "Connected."
Click the image below to check more products
More products you can choose
ATI Electronics was founded in 1999. ATI Electronics offers Bluetooth noise canceling headsets,bluetooth carkit, bluetooth mono headsets, Bluetooth stereo headsets,Bluetooth speaker,Bluetooth keyboard and mouse,bluetooth gaming accessories,moblie phones,Tablet computer,pagers, etc.We offer high quality and competitive bluetooth products,They are all our own tooling and patent.


text:
|This article is about a/an monster in Power Rangers Operation Overdrive.
description to be added
Character History
A rapier-wielding monster with glass slippers at the sides of its head that was summoned by Kamdor alongside other monsters to battle the Overdrive Rangers, so he could snag the Star of Isis located somewhere in the Everglades. He fought Tyzonn after being created. He was the fifth monster to be destroyed by the Red Sentinel Ranger and his tornado finisher.
to be added
Modus and Arsenal
- to be added
- Prince Warrior resembles the DinoStegazord of Power Rangers Dino Thunder, the reason for this is because Prince Warrior's Boukenger counterpart, Prince, as with each primary antagonist and each individual monster of the week was visually designed as an homage to the various robots and other mecha piloted by the protagonists of the 29 previous Super Sentai Series (except for J.A.K.Q. Dengekitai), as Boukenger was the 30th anniversary series. Prince's look was based on the DinoStegazord's counterpart, the KillerOh of Bakuryuu Sentai Abaranger.
- The original footage of the Prince Warrior fighting the DriveMax Megazord & Flash Point Megazord was cut due to the Prince Warrior's counterpart Prince kissing the DriveMax's counterpart DaiBouken.
See Also
- Prince (Boukenger) - Super Sentai counterpart in Boukenger. See comparison page.


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Edible Flower Heirloom Seed Bundle
The Little Veggie Patch Co
This product is currently sold out.
Our complete range of heirloom edible flower seeds. These plants will not only help to attract pollinators, but also have a useful home in the kitchen.
Hyssop 'Anise' Heirloom Seeds
Calendula 'Pacific Beauty' Heirloom Seeds
Cornflower 'Dwarf Polka Dot'
Marigold 'Petite Series Mixed'
Nasturtium 'Double Jewel'
Sunflower 'Hi Sun'
**Seeds subject to seasonal availability and a similar variety will be subbed in for out-of-stock items**
**Shipping - Not to Western Australia**


text:
- Cameron Nichols
- 2 years ago
- Views:
1 ANSWER SET PROGRAMMING Tran Cao Son Department of Computer Science New Mexico State University Las Cruces, NM 88011, USA October 2005
2 Acknowledgement This tutorial contains some materials from tutorials on answer set programming and on knowledge representation and logic programming from those provided by Chitta Baral, available at Michael Gelfond, available at Tran Cao Son 1
3 Introduction Answer Set Programming Answer set programming is a new programming paradigm. It is introduced in the late 90 s and manages to attracts the intention of different groups of researchers thanks to its: declarativeness: programs do not specify how answers are computed; modularity: programs can be developed incrementally; expressiveness: answer set programming can be used to solve problems in high complexity classes (e.g. Σ 2 P, Π 2 P, etc.) Answer set programming has been applied in several areas: reasoning about actions and changes, planning, configuration, wire routing, phylogenetic inference, semantic web, information integration, etc. Tran Cao Son 2
4 Purpose Introduce answer set programming Provide you with some initial references, just in case... you get excited about answer set programming Tran Cao Son 3
5 Outline Foundation of answer set programming: logic programming with answer set semantics (syntax, semantics, early application). Answer set programming: general ideas and examples Application of answer set programming in Knowledge representation Constraint satisfaction problem Combinatoric problems Reasoning about action and change Planning and diagnostic reasoning Current issues Tran Cao Son 4
7 Logic Programming and Answer Set Semantics Terminologies many brorrowed from classical logic variables: X, Y, Z, etc. object constants (or simply constants): a, b, c, etc. function symbols: f, g, h, etc. predicate symbols: p, q, etc. terms: variables, constants, and f(t 1,..., t n ) such that t i s are terms. atoms: p(t 1,..., t n ) such that t i s are terms. literals: atoms or an atom preceded by. naf-literals: atoms or an atom preceded by not. gen-literals: literals or a literal preceded by not. ground terms (atoms, literals) : terms (atoms, literals resp.) without variables. Tran Cao Son 6
8 Logic Programming and Answer Set Semantics First Order Language, Herbrand Universe, and Herbrand Base L a first order language with its usual components (e.g., variables, constants, function symbols, predicate symbols, arity of functions and predicates, etc.) U L Herbrand Universe of a language L: the set of all ground terms which can be formed with the functions and constants in L. B L Herbrand Base of a language L: the set of all ground atoms which can be formed with the functions, constants and predicates in L. Example: Consider a language L 1 with variables X, Y ; constants a, b; function symbol f of arity 1; and predicate symbol p of arity 1. U L1 = {a, b, f(a), f(b), f(f(a)), f(f(b)), f(f(f(a))), f(f(f(b))),...}. B L1 = {p(a), p(b), p(f(a)), p(f(b)), p(f(f(a))), p(f(f(b))), p(f(f(f(a)))), p(f(f(f(b)))),...}. Tran Cao Son 7
9 Logic Programming and Answer Set Semantics A logic program rule is of the form Logic Programs Syntax a 0 a 1,...,a n,not a n+1,...,not a n+k (1) where a s are atoms (of a first order language L); not a is called a naf-atom. a 0 head (the left hand side) a 1,..., a n body (the right hand side) Definition 1 A logic program is a set of logic programming rules. The language L of a program Π is often given implicitly. Remark 1 From now on, we will say a rule (resp. a program) instead of a logic programming rule (resp. a logic program), for short; Special cases: a 0 (n = 0) is called a fact; a 1,..., a n (a 0 is missing) is called a constraint or a goal; k = 0 the rule is called a positive rule. Tran Cao Son 8
10 Logic Programming and Answer Set Semantics Main Definitions ground(r, L): the set of all rules obtained from r by all possible substitution of elements of U L for the variables in r. Example 1 Consider the rule p(f(x)) p(x). and the language L 1. Then ground(r, L 1 ) will consist of the following rules: p(f(a)) p(a). p(f(b)) p(b). p(f(f(a))) p(f(a)). p(f(f(b))) p(f(b)).. For a program Π: ground(π, L) = r Π ground(r, L) L Π : The language of a program Π is the language consists of the constants, variables, function and predicate symbols (with their corresponding arities) occurring in Π. In addition, it contains a constant a if no constant occurs in Π. ground(π) = r Π ground(r, L Π ). Tran Cao Son 9
11 Logic Programming and Answer Set Semantics Example 2 Π: p(a). p(b). p(c). p(f(x)) p(x). ground(π): p(a). p(b). p(c). p(f(a)) p(a). p(f(b)) p(b). p(f(c)) p(c). p(f(f(a))) p(f(a)). p(f(f(b))) p(f(b)). p(f(f(c))) p(f(c)).. Tran Cao Son 10
12 Logic Programming and Answer Set Semantics Intuition and Examples of Using LP (Positive Programs) Meaning of a rule A positive rule a 0 a 1,..., a n can be viewed as the disjunction a 0 a 1... a n which says that if a 1,...,a n are true then a 0 is true. A rule a 0 a 1,...,a n,not a n+1,...,not a n+k states that if a 1,..., a n are true and none of the a n+1,...,a n+k can be proven to be true then a 0 is true. A constraint a 1,...,a n,not a n+1,...,not a n+k holds if some a i (1 i n) is false or some a j (n + 1 j n + k) is true. Knowledge representation using LP-rules flies(x) bird(x). wet grass sprinkler on. rain humid, hot. love(x, Y ) love(y, X). if X is a bird, then X flies The grass is wet if the sprinkler is on hot and humid causes rain Love is a symmetric relationship Tran Cao Son 11
13 Logic Programming and Answer Set Semantics Herbrand Interpretation Definition 2 The Herbrand universe (resp. Herbrand base) of Π, denoted by U Π (resp. B Π ), is the Herbrand universe (resp. Herbrand base) of L Π. Example 3 For Π = {p(x) q(f(x), g(x)). r(y ) } the language of Π consists of two function symbols: f (arity 1) and g (arity 2); p, q, and r are predicate symbols; variables X, Y ; and a (added) constant a. U Π = U LΠ = {a, f(a), g(a), f(f(a)), g(f(a)), g(f(a)), g(g(a)), f(f(f(a))),...} B Π = B LΠ = {p(a), q(a, a), r(a), p(f(a)), q(a, f(a)), r(f(a)),...} Definition 3 (Herbrand Interpretation) A Herbrand interpretation of a program Π is a set of atoms from its Herbrand base. Tran Cao Son 12
14 Logic Programming and Answer Set Semantics Semantics Positive Programs without Constraints Let Π be a positive proram and I be a Herbrand interpretation of Π. I is called a Herbrand model of Π if for every rule a 0 a 1,...,a n, if a 1,...,a n are true with respect to I (or a 1,..., a n I) then a 0 is also true with respect to I. Definition 4 The least Herbrand model for a program Π is called the minimal model of Π and is denoted by M Π. Computing M P. Let Π be a program. We define a fixpoint operator T Π that maps a set of atoms (of program Π) to another set of atoms as follows. T Π (X) = {a a B Π, there exists a rule a a 1,..., a n in Π s. t. a i X} (2) Note: By a a 1,...,a n in Π we mean there exists a rule b b 1,..., b n in Π (that might contain variables) and a ground substitution σ such that a = bσ and a i = b i σ. Remark 2 The operator T Π is often called the van Emden and Kowalski s iteration operator. Tran Cao Son 13
15 Logic Programming and Answer Set Semantics Some Examples For Π = {p(f(x)) p(x). q(a) p(x).} we have U Π = {a, f(a), f(f(a)), f(f(f(a))),...} and B Π = {q(a), p(a), p(f(a)), p(f(f(a))),...} Computing T Π (X): For X = B Π, T Π (X) = {q(a)} {p(f(t)) t U Π }. For X =, T Π (X) =. For X = {p(a)}, T Π (X) = {q(a), p(f(a))}. We have that M Π = (Why?). Tran Cao Son 14
16 Logic Programming and Answer Set Semantics Properties of T Π T Π is monotonic: T Π (X) T Π (Y ) if X Y. T Π has a least fixpoint that can be computed as follows. 1. Let X 1 = T Π ( ) and k = 1 2. Compute X k+1 = T Π (X k ). If X k+1 = X k then stops and return X k. 3. Otherwise, increase k and repeat the second step. Note: The above algorithm will terminate for positive program Π with finite B Π. We denote the least fix point of T Π with T Π ( ) or lfp(t Π ). Theorem 1 M Π = lfp(t Π ). Theorem 2 For every positive program Π without constraint, M Π is unique. Tran Cao Son 15
17 Logic Programming and Answer Set Semantics More Examples For Π 1 = {p(x) q(f(x), g(x)). r(y ) } we have that U Π1 = {a, f(a), g(a), f(f(a)), g(f(a)), g(f(a)), g(g(a)), f(f(f(a))),...} B Π1 = {p(a), q(a, a), r(a), p(f(a)), q(a, f(a)), r(f(a)),...} Computing M Π : X 0 = T Π1 ( ) = {r(a), r(f(a)), r(g(a)), r(f(f(a))),...} X 1 = T Π1 (X 0 ) = X 0 So, lfp(π 1 ) = {r(a), r(f(a)), r(g(a)), r(f(f(a))),...}. For Π 2 = {p(f(x)) p(x). q(a) p(x).} U Π2 = {a, f(a), f(f(a)), f(f(f(a))),...} B Π2 = {q(a), p(a), p(f(a)), p(f(f(a))),...} Computing M Π2 : X 0 = T Π2 ( ) = X 1 = T Π2 (X 0 ) = X 0 So, lfp(π 2 ) =. Tran Cao Son 16
18 Logic Programming and Answer Set Semantics For Π 3 = {p(f(x)) p(x). q(a) p(x). p(b).} U Π3 = {a, b, f(a), f(b), f(f(a)), f(f(b)), f(f(f(a))),...} B Π3 = {q(a), q(b), p(a), p(b), p(f(a)), p(f(b)), p(f(f(a))),...} Computing M Π3 : X 0 = T Π3 ( ) = {p(b)} X 1 = T Π3 (X 0 ) = {p(b), q(a), p(f(b))} X 2 = T Π3 (X 1 ) = {p(b), q(a), p(f(b)), p(f(f(b)))}... So, lfp(t Π3 ) = {q(a)} {p(f i (b)) i = 0, 1,...}. For Π 4 = {p a. q b. a.}, M Π4 = {a, p}. For Π 5 = {p p.}, M Π5 = For Π 6 = {p p. q.}, M Π6 = {q}. For Π 7 = {p(b). p(c). p(f(x)) p(x).},m Π7 = {p(f n (b)) n = 0,..., } {p(f n (c)) n = 0, 1....,} Tran Cao Son 17
19 Logic Programming and Answer Set Semantics Entailment For a program Π and an atom a, Π entails a (with respect to the minimal model semantics), denoted by Π = a, iff a M Π. We say that Π entails a (with respect to the minimal model semantics), denoted by Π = a, iff a M Π. Example 4 Let p(f(x)) p(x). Π = q(a) p(x). p(b). We have that M Π = lfp(t Π ) = {q(a)} {p(f i (b)) i = 0, 1,...} where f i (b) = f(f(... (f(b)))) (f repeated i times) So, we say: Π = q(a), Π = q(b), and Π = p(f i (b)) for i = 0, 1,... Tran Cao Son 18
20 Logic Programming and Answer Set Semantics Entailment Another Example Example 5 Consider the parent-child database with facts of the form p(x, Y ) (X is a parent of Y ). We can define the ancestor relationship, a(x, Y ) (X is an ancestor of Y ), using the following rules Π a = a(x, Y ) p(x, Y ). a(x, Y ) p(x, Z), a(z, Y ). Given the set of facts I = {p(a, b), p(b, c), p(c, d)}, let Π = Π a I. We can easily compute M Π = I {a(x, Y ) p(x, Y ) I} {a(a, c), a(a, d), a(b, d)} So, Π = a(a, c) and Π = a(a, d), i.e., a is an ancestor of c and d; on the other hand, Π = a(d, a), i.e., d is not an ancestor of a. Tran Cao Son 19
21 Logic Programming and Answer Set Semantics Consider a directed graph G described by a set of atoms of the form edge(x, Y ). The following program can be used to determine whether there is a path connecting two nodes of G. reachable(x, Y ) edge(x, Y ) reachable(x, Y ) edge(x, Z), reachable(z, Y ) Π G = edge(a, b) edge(b, c) edge(c, a)... It can be shown that for every pair of nodes p and q of the graph G, reachable(p, q) belongs to M ΠG iff there exists a path from p to q in the graph G. Remark 3 Reasoning using positive programs assumes the closed world assumption (CWA): anything, that cannot be proven to be true, is false. Tran Cao Son 20
22 Logic Programming and Answer Set Semantics Semantics General Logic Programs without Constraints Recall that a program is a collection of rules of the form a a 1,...,a n,not a n+1,not a n+k. Let Π be a program and X be a set of atoms, by Π X we denote the program obtained from ground(π) by 1. Deleting from ground(π) any rule a a 1,..., a n,not a n+1,not a n+k for that {a n+1,..., a n+k } X, i.e., the body of the rule contains a naf-atom not a l and a l belongs to X; and 2. Removing all of the naf-atoms from the remaining rules. Remark 4 The above transformation is often referred to as the Gelfond-Lifschitz transformation. Remark 5 Π X is a positive program. Definition 5 A set of atoms X is called an answer set of a program Π if X is the minimal model of the program Π X. Theorem 3 For every positive program Π, the minimal model of Π, M Π, is also the unique answer set of Π. Tran Cao Son 21
23 Logic Programming and Answer Set Semantics Detailed Computation Consider Π 2 = {a not b. sets {a} and {b} b not a.}. We will show that its has two answer S 1 = S 2 = {a} S 3 = {b} S 4 = {a, b} Π S 1 2 : Π S 2 2 : Π S 3 2 : Π S 4 2 : a a b b M S Π 1 = {a, b} M S 2 Π 2 = {a} M S 2 Π 3 = {b} M P S 4 = 2 M S Π 1 S 1 M S 2 Π 2 = S 2 M S 2 Π 3 2 NO Y ES Y ES NO = S 3 M Π S 4 2 S 4 Assume that our language contains two object constants a and b and consider Π = {p(x) not q(x). q(a) }. We show that S = {q(a), p(b)} is an answer set of Π. We have that Π S = {p(b) q(a) } whose minimal model is exactly S. So, S is an answer set of Π. Tran Cao Son 22
24 Logic Programming and Answer Set Semantics Π 4 = {p not p.} We will show that P does not have an answer set. S 1 =, then Π S 1 4 = {p } whose minimal model is {p}. {p} implies that S 1 is not an answer set of Π 4. S 2 = {p}, then Π S 2 4 = whose minimal model is. {p} implies that S 2 is not an answer set of Π 4. This shows that P does not have an answer set. In computing answer sets, the following theorem is useful: Theorem 4 Let Π be a program. 1. Let r be a rule in ground(p) whose body contains an atom a that does not occur in the head of any rule in ground(p). Then, S is an answer set of Π iff S is an answer set of ground(p) \ {r}. 2. Let r be a rule in ground(p) whose body contains a naf-atom not a that does not occur in the head of any rule in ground(p). Let r be the rule obtained from r by removing not a. Then, S is an answer set of P iff S is an answer set of ground(p) \ {r} {r }. Tran Cao Son 23
25 Logic Programming and Answer Set Semantics Examples about Answer Sets Remark 6 A program may have zero, one, or more than one answer sets. Π 1 = {a not b.}. Π 1 has a unique answer set {a}. Π 2 = {a not b. b not a.}. The program has two answer sets: {a} and {b}. Π 3 = {p a. a not b. b not a.} The program has two answer sets: {a, p} and {b}. Π 4 = {a not b. b not c. d.} Answer sets: {d, b}. Π 5 = {p not p.} No answer set. Π 6 = {p not p, d. r not d. d not r.} Answer set {r}. Tran Cao Son 24
26 Logic Programming and Answer Set Semantics Entailment w.r.t. Answer Set Semantics For a program Π and an atom a, Π entails a, denoted by Π = a, if a S for every answer set S of Π. For a program Π and an atom a, Π entails a, denoted by Π = a, if a S for every answer set S of Π. If neither Π = a nor Π = a, then we say that a is unknown with respect to Π. Remark 7 Π does not entail a DOES NOT IMPLY that Π entails a, i.e., reasoning using answer set semantics does not employ the closed world assumption. Example 6 Π 1 = {a not b.}. Π 1 has a unique answer set {a}. Π 1 = a, Π 1 = b. Π 2 = {a not b. b not a.}. The program has two answer sets: {a} and {b}. Both a and b are unknown w.r.t. Π 2. Π 3 = {p a. a not b. b not a.} The program has two answer sets: {a, p} and {b}. Everything is unknown. Tran Cao Son 25
27 Logic Programming and Answer Set Semantics Π 3 = {a not b. b not c. d.} Answer sets: {d, b}. Π 3 = b; Π 3 = a; etc. Π 4 = {p not p.} No answer set. p is unknown. Π 5 = {p not p, d. r not d. d not r.} Answer set {r}. Π 5 = r; Π 5 = p; etc. Π 6 = {p not a. p not b. a not b. b not a.} Two answer sets: {p, a} and {p, b}. So, Π 6 = p but Π 6 = a and Π 6 = a? (likewise b). Π 7 = {q not r. r not q. p not p. p not r.} One stable model: {p, q}. So, Π 7 = p and Π 7 = q. Tran Cao Son 26
28 Logic Programming and Answer Set Semantics Further intuitions behind the semantics A set of atoms S is closed under a program Π if for all rules of the form a 0 a 1,...,a m,not a m+1,...,not a n. in Π, {a 1,...,a m } S and {a m+1,..., a n } S = implies that a 0 S. A set of atoms S is said to be supported by Π if for all p S there is a rule of the form p a 1,...,a m,not a m+1,...,not a n. in Π, such that {a 1,...,a m } S and {a m+1,..., a n } S =. A set of atoms S is an answer set of a program Π iff (i) S is closed under Π and (ii) there exists a level mapping function λ (that maps atoms in S to a number) such that for each p S there is a rule in Π of the form p a 1,..., a m,not a m+1,...,not a n. such that {a 1,...,a m } S, {a m+1,..., a n } S = and λ(p) > λ(a i ), for 1 i m. Note that (ii) above implies that S is supported by Π. Tran Cao Son 27
30 Logic Programming and Knowledge Representation Our knowledge Commonsense Reasoning is often incomplete (it does not contain complete information about the world), and contains defaults (rules which have exceptions, also called normative sentences). contains preferences between defaults (prefer a conclusion/default). For this reasons, we often jump to conclusions (ignore what we do not now), and know to deal with exceptions and preferences. Example 7 We know Normally, birds fly. Normally, computer science students can program. Normally, students work hard. Normally, things do not change. Normally, students do not watch TV. Normally, the speed limit on highways is 70 mph. Normally, it is cold in December. From this, we make conclusions such as Tweety flies if we know that Tweey is a bird; Monica can program if she is a computer science student; etc. Tran Cao Son 29
31 Logic Programming and Knowledge Representation Representing Defaults Normally, a s are b s. b(x) a(x),not ab(r, X) 1 Normally, birds fly. f lies(x) bird(x), not ab(bird f ly, X) Normally, animals have four legs. numberof legs(x, 4) animal(x), not ab(animal, X) Normally, fishs swim. swim(x) f ish(x), not ab(f ish, X) Normally, computer science students can program. can program(x) student(x), is in(x, cs),not ab p (X) Normally, students work hard. hard working(x) student(x), not ab(x) Typically, classes start at 8am. start time(x, 8am) class(x), not ab(x) 1 r is the name of the statement; ab(x) or ab r(x) can also be used. Tran Cao Son 30
32 Logic Programming and Knowledge Representation Example 8 (Birds) Suppose that we know r 1 : Normally, birds fly. r 3 : Penguins are birds. r 3 : Penguins do not fly. r 4 : Tweety is a penguin. r 5 : Tim is a bird. r 1 : flies(x) bird(x),not ab(r 1, X) r 2 : bird(x) penguin(x) Π b = r 3 : ab(r 1, X) penguin(x) r 4 : penguin(tweety) r 5 : bird(tim) Answer set of Π b :? Tran Cao Son 31
33 Logic Programming and Knowledge Representation Π b = Answer set of Π b : r 1 : flies(x) bird(x),not ab(r 1, X) r 2 : bird(x) penguin(x) r 3 : ab(r 1, X) penguin(x) r 4 : penguin(tweety) r 5 : bird(tim) {bird(tim), flies(tim), penguin(tweety), ab(r 1, tweety), bird(tweety) Π b = flies(tim) and Π b = flies(tweety) Tran Cao Son 32
34 Logic Programming and Knowledge Representation Defaults Example Example 9 (Animals) Consider the following information: Normally lions and tigers are cats. Sam and John are lions. Sam is not a cat. Sam is a sea lion. This information can be represented by the following program Π a = r 1 : cat(x) lion(x),not ab(r 1, X) r 2 : cat(x) tiger(x),not ab(r 2, X) r 3 : lion(x) sea lion(x) r 4 : ab(r 1, X) sea lion(x) r 5 : sea lion(sam) r 6 : lion(john) We can check that Π a entails that sam is a lion but not a cat while john is a cat which is a lion. Tran Cao Son 33
35 Logic Programming and Knowledge Representation Defaults More Examples Example 10 We know that computers are normally fast machines, the commodore is a slow machine because it is an old one. This can be represented by the following program: Π c = r 1 : fast machine(x) computer(x),not ab(x) r 2 : old(x) comodore(x) r 3 : computer(x) comodore(x) r 4 : ab(x) old(x) The Boeing 747, concord, and FA21314 are airplanes. Airplanes normally fly unless they are out of order. FA21314 is out of order. r 1 : flies(x) airplane(x),not ab(x) r 2 : ab(x) out of order(x) r Π airplanes = 3 : airplane(boeing 747) r 4 : airplane(concord) r 5 : airplane(fa21324) r 6 : out of order(fa21324) Tran Cao Son 34
37 Extensions of Logic Programming and Computing Answer Sets Additional Features for Knowledge Representation and Reasoning To add expressiveness and make logic programming a more suitable language for knowledge representation and reasoning, additional features and constructors are introduced: classical negation: instead of atoms, literals are used in the rule l 0 l 1,...,l n,not l n+1,...,not l n+k where l i is a literal (an atom a or its negation a). This will allow us to represent and reason with negative information. epistemic disjunction: rule is allowed to have epistemic disjunction in the head l 0 or... or l m l m+1,...,l m+n,not l m+n+1,...,not l m+n+k where or is a epistemic disjunction. This rule states that if l m+1,..., l m+n are true and there is no reason for believing that the l m+n+1,..., l m+n+k are true then at least one of the l 0,..., l m is believed to be true. nested expression: allowing not not l. Tran Cao Son 36
38 weighted-atom: Extensions of Logic Programming and Computing Answer Sets l{l 0 = w 0,..., l k = w k,not l k+1 = w k+1,...,not l k+n = w k+n }u where l i s are a literal, w i are integers, and l and u are two integers. This atom is true with respect to a set of literals S if l 0 j k l j S w j + k+1 j k+n Special case: choice atom w i = 1 for every i. l j S w j u Programs with weight constraints are defined by allowing weight atoms to appear in place of atoms. Answer set semantics: defined accordingly. See for example, M. Gelfond and V. Lifschitz, Classical negation in logic programs and disjunctive databases, New Generation Computing, 1991, pp V. Lifschitz, L. R. Tang and H. Turner, Nested expressions in logic programs, Annals of Mathematics and Artificial Intelligence, Vol. 25, 1999, pp I. Niemelä and P. Simons. Extending the Smodels System with Cardinality and Weight Constraints.Logic-Based Artificial Intelligence, pp Kluwer Academic Publishers, Tran Cao Son 37
39 Extensions of Logic Programming and Computing Answer Sets Using Classical Negation Π b = r 1 : flies(x) bird(x),not ab(r 1, X) r 2 : bird(x) penguin(x) r 3 : ab(r 1, X) penguin(x) r 4 : penguin(tweety) r 5 : bird(tim) In the bird example, Penguins do not fly is more intuitive than Normally, penguins do not fly. So, r 3 of Π b should be changed to r 3 : flies(x) penguin(x). Doing so will make the program Π b inconsistent! Obviously, r 1 does not account for the class of birds who do not fly. We should change the rule r 1 to r 1 : flies(x) bird(x),not ab(r 1, X),not flies(x) The new program, Π b = Π b \ {r 1, r 3 } {r 1, r 3} will correctly answer the same questions such as does Tim flies and does Tweety fly? Tran Cao Son 38
40 Suppose that we have a list of professor and their courses: Extensions of Logic Programming and Computing Answer Sets Professor Course mike ai sam db staff C where staff stands for someone an unknown professor who might be different than mike and sam. This list can be expressed by a set of atoms of the form teach(p, C) (P teaches C): teach(mike, ai), teach(sam, db), and teach(staf f, c). By default, we know that if a professor P teaches the course C, then (P, C) will be listed (and hence the atom teach(p, C) will be present.) Thus, by default, professor P does not teach the course C if teach(p, C) is not present. The exception to this rule are the courses taught by staff. This leads to the following two rules: teach(p, C) not teach(p, C), not ab(p, C). ab(p, C) teach(staf f, C) This will allow us to conclude that mike teaches ai but we do not know whether he teaches c or not. Tran Cao Son 39
41 Extensions of Logic Programming and Computing Answer Sets Answer Sets of Programs with Constraints For a set of ground atoms S and a constraint c a 0,..., a n,not a n+1,...,not a n+k we say that c is satisfied by S if {a 0,..., a n } \ S or {a n+1,..., a n+k } S. Let Π be a program with constraints. Let Π O = {r r Π, r has non-empty head} (Π O is the set of normal logic program rules in Π) and (Π C is the set of constraints in Π). Π C = Π \ Π O Definition 6 A set of atoms S is an answer sets of a program Π if it is an answer set of Π O and satisfies all the constraints in ground(π C ). Example 11 Π 2 = {a not b. b not a.} has two answer sets {a} and {b}. But, Π 2 = {a not b. b not a. not a} has only one answer set {a}. Tran Cao Son 40
42 Extensions of Logic Programming and Computing Answer Sets Computing Answer Sets Complexity: The problem of determining the existence of an answer set for finite propositional programs (programs without function symbols) is NP-complete. For programs with disjunctions, function symbols, etc. it is much higher. A consequence of this property is that there exists no polynomial-time algorithm for computing answer sets. Special cases: answer sets of positive programs without function symbols can be computed in polynomial time in the size of the program. A good survey on the complexity and expresiveness of different classes of logic programs can be found in Chitta Baral. Knowledge representation, reasoning and declarative problem solving, Cambridge University Press, Answer set solvers: Programs that compute answer sets of (finite and grounded) logic programs. Two main approaches: Tran Cao Son 41
43 Extensions of Logic Programming and Computing Answer Sets Direct implementation: Due to the complexity of the problem, most solvers implement a variation of the generate-and-test algorithm. The advantage of this approach is that we are free to invent! Many systems: Smodels available at Dlv available at deres available at nomore available at Using SAT solvers: A program Π is translated into a satisfiabilty problem F Π and a call to a SAT solver is made to compute solution of F Π. The main task of this approach is to write the program for the conversion from Π to F Π. Recent discoveries ensure that there is an one-to-one correspondence between solutions of F Π and answer sets of Π (e.g., see paper from the ASSAT web site). Two systems: Cmodels available at ASSAT available at Remark 8 Most of the above systems make use of lparse, a grounding program for logic programs with function symbols (typed) and weight constraints. The program is available at the Smodels web site. Tran Cao Son 42
44 Extensions of Logic Programming and Computing Answer Sets Remark 9 A Java implementation of Smodels, called Jsmodels, is available at Usage of lparse and Smodels lparse: a preprocessor for programs using as input to Smodels. Some restrictions apply: Finite domains: every variable is typed and has a finite domain; Safe rule: variables appear in the head of a rule must occur in the body of the rule, in a predicate that specifies the domain of the variable; Built-in predicates: assign, plus, minus, etc.. (see lparse user s manual for more). Do not use them in your programs or you will get errors. Command line: lparse <options> prog1 prog2... smodels number of models Tran Cao Son 43
46 Answer Set Programming Brief History and References Answer set programming was introduced in V. W. Marek, M. Truszczynski. Stable models and an alternative logic programming paradigm. In The Logic Programming Paradigm, K.R. Apt, V.W. Marek, M. Truszczynski, D.S. Warren (eds.), pp Springer-Verlag, I. Niemelä. Logic programming with stable model semantics as a constraint programming paradigm. Annals of Mathematics and Artificial Intelligence, 25(3,4): , Take off thanks to the development of several answer set solvers (Smodels and Dlv), the application of answer set programming in several applications such as planning, system configuration, cryptography, NASA s application, etc. 2001: first symposium on answer set programming: Answer Set Programming: Towards Efficient and Scalable Knowledge Representation and Reasoning, now: several symposia on ASP (http://wasp.unime.it/) now: several papers on answer set programming have been published. Tran Cao Son 45
47 Answer Set Programming Main Idea Given a problem P, whose solutions are S 1,..., S n which can be computed by generating a hypothetical solution and testing whether it is really a solution. This process is very similar to the process of computing answer sets of a logic program Π: given a program Π its answer sets can be computed by generating a set of atoms X and checking whether X is an answer set of Π This gives us the idea: Solve P by representing P as a logic program Π P whose answer sets correspond one-to-one to S 1,..., S n using the follong steps: Repesenting P as Π P ; Computing answer sets of Π P ; and Converting answer sets of Π Π to solutions of P Tran Cao Son 46
49 Examples Graph Coloring Coloring Figure 1: Graph Coloring Problem Problem: Given a (bi-directed) graph and three colors red, green, and yellow. Find a color assignment for the nodes of the graph such that no edge of the graph connects two nodes of the same color. Tran Cao Son 48
50 Examples Graph Coloring Example 12 (Graph coloring problem) Given a (bi-directed) graph and three colors red, green, and yellow. Find a color assignment for the nodes of the graph such that no edge of the graph connects two nodes of the same color. Representation: A graph can be specified by the set of nodes and the set of edges. Solution: A mapping from the set of nodes to the set of colors {red, green, yellow} such that no edge connects two nodes of the same color. Solving the problem (manualy): Numbering the nodes from 1 to n Assigning each node a color Checking if the assignment is a solution, i.e., satisfies the constraints no edge connects two nodes of the same color Tran Cao Son 49
51 Examples Graph Coloring Program Writing a program to solve the graph coloring problem: Graph representation: The nodes: node(1),...,node(n). The edges: edge(i, j). Solution repesentation: use the predicate color(x, Y ) - node X is assigned the color Y. Generating the solutions: Each node is assigned one color. The three rules color(x, red) not color(x, green), not color(x, yellow). (3) color(x, green) not color(x, red), not color(x, yellow). (4) color(x, yellow) not color(x, green), not color(x, red). (5) or the weighted rule 1{color(X, red), color(x, yellow), color(x, green)}1 node(x). can be used. (The weighted rule says that each node should be colored using exactly one color.) Tran Cao Son 50
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The iMouse M20 Wireless Ergonomic Optical Mouse from Adesso is a 2.4 GHz RF wireless mouse that offers 30' (9.1m) of wireless freedom and eliminates the constraints wired mice often cause. Its optical sensor tracking method allows you to work on any surface with better speed and accuracy. In addition, this mouse includes 3 distinct levels of DPI resolution - 500, 1000 and 1500. For precise targeting it features 500 DPI, for quick response 1000 DPI, and for fast maneuvers 1500 DPI. You can easily switch between these DPI resolutions with the DPI switch button located on top of the mouse. All these features, along with its ergonomic design, provide better control, response, and comfort, with minimal hand movement.
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The club resort is an exquisite piece of architecture dating from the sixteenth century. It is the ideal place to stay during guests' journey of discovery of the ancient citadel of Machu Picchu. Offering a total of 126 guest rooms, the hotel also features a caf�, bar, restaurant, conference facilities and room and laundry services.
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I've decided to take up the 20 Days of WoW Blogging Challenge by Saga of Spellbound to commemorate my 3 month anniversary at the end of January. I also figured it would be a good way to get the writing juices flowing and generate some content between the usual gold making posts. On with the show!
Before I started this blog, I actually did some guest posts for other blogs, so I've decided to cover both my first blog post ever, and my first post on this blog.
My First Blog Post
The first blog post I ever wrote was How Does One Measure an Economy over at JMTC. At the time of writing that post I was fiddling around with a php script to quantify a market, so see how it ebbed and flowed, and to compare different economies. It was fun while it lasted, but a change in the TUJ API I was using made me abandon it, that and it wasn't really all that useful. This article was mostly a compendium of my thoughts during the design process for this script.
First Post on The Golden Crusade
How to Exit Gracefully From the Gold Making Scene was my first post returning, again, to goblineering. I had realized how much I could have done to ease my transition back into gold making, so I decided to share some Do's and Don'ts of the process.
Check out my other posts in the 20 Days of WoW Blogging Challenge


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|Publication number
|Publication type
|Application number
|Publication date
|Jan 24, 2012
|Filing date
|Sep 27, 2007
|Priority date
|Sep 27, 2006
|Fee status
|Also published as
|Publication number
|Paul Andrew Edwards, John Hennessy
|Original Assignee
|Electronics For Imaging, Inc.
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (71), Classifications (6), Legal Events (2)
|External Links: USPTO, USPTO Assignment, Espacenet
This application claims the benefit of U.S. Provisional Application No. 60/847,567 filed on Sep. 27, 2006. The disclosure of the above application is incorporated herein by reference.
The present disclosure relates to ink jet printers and, more particularly, relates to industrial ink jet printers having a modular construction.
The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Industrial ink jet printing systems are designed to serve users with specific and varied requirements. Some users may only need a relatively simple configuration consisting of an unwind, print zone, ink curing zone and a rewind spindle, while other users would also require a web cleaner, web pretreatment zone, a web guide, additional curing zones or many other application specific modules. In addition, digital printing system design must make use of highly accurate backplane surfaces to which the web transport elements (drive rollers, idlers, dancer rolls, etc) and print hardware are mounted to. In order to meet the highly varied needs of all users in the marketplace, it is necessary to create many custom printing systems, each one special, highly engineered and not cost effective enough to wider markets.
As an alternative, one very large system could be designed that had space for all possible configurations, features and options. This approach would reduce the engineering effort, and standardize the design and construction. However, it would force all users to purchase a machine that is potentially much larger and more expensive than they need, again not cost effective. From an engineering standpoint, it would also necessitate a very large back plane, which is more difficult to keep in a true plane, resulting in negative performance characteristics.
Previous work in digital press design revolved around custom printer design specific to a user, or a design lacking the options or features that users need. Digital printing systems lack the ability to cost effectively add or change features and options for their varied users.
The present teachings are superior to methods previously used because it uses a modular approach to digital printer system design. The design comprises a base module containing the main drive elements and print zone, common on all print systems. This module is made up of the main module back plane, and a machine base "rail system" which would allow additional modules to be added before or after the base module. The rail system is expandable and provide for easy drop in and bolt up add on modules. Add on modules are designed for unwinding substrates, web cleaning, corona treating, static control, pre-treatment, coating, curing, graphic printing, additional curing, laminating, die cutting, waste removal, serial number printing, sheeting, rewind, or any other feature or further process that the digital market required.
This approach standardizes the designs significantly, allows for easy expansion of features, maintains appropriate cost profiles in that users pay for the modules they need, and not for modules or features they do not. It also allows changes to be made in the field, as user's needs changes or expand. Finally, from an engineering standpoint, smaller backplanes are easier and more cost effective to manufacture. Additionally, when a design change is necessary, it would affect only the design of that module, and would not affect the entire printer system.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.
The present teachings use a modular approach to designing and building digital printers for industrial use. According to these teachings, print modules are designed for specific purposes and added to the expandable base support. The base support can consist of a main backplane or backplanes and a rail system that can be expanded to accept removable modules at various positions along the base support. In those embodiments using a rail system, the rail system provides basic support and alignment for modules 12, both during initial build and during field modifications. Options and features can be organized logically, placed into the rail system, aligned and affixed in place using standard fasteners and fastening methods. One or more printing functions are designed into a module depending on the characteristics required. Examples may include a module that handles the unwind spindle and tension dancer functions, a module that handles web cleaning and corona treatment and modules that include specific UV lamps from outside vendors. If a change to a configuration is needed, or a new capability is desired, the existing modules can conveniently be loosened and slid down or removed to make room for the new module. With this expandable rail system, feature upgrades can be done with minimal effort.
With particular reference to the figures, a modular ink jet printer system 10 is provided having a plurality of modular components or modules 12. Each of the plurality of modules 12 can be either stand alone modules that are arranged inline and optionally mounted together with tie bars 14 (
With reference to
With reference to
In some embodiments, as illustrated in
In some embodiments, it is desirable to position the plurality of modules 12 accurately to base support 16 and to other modules 12 before securing them. To this end, such positioning and/or alignment of modules 12 can be accomplished by machining a receptacle (such as a locating aperture 30 that could include a circular hole, half-hole, or other shape) into the edge of module 12. A corresponding single pin 32 can extend from base support 16 and communicate with locating apertures 30 from multiple modules 12 as illustrated in
Hurdles overcome within this design include ensuring accurate module placement, designing modules that contain complementary functionality, and standardizing modules 12 so that they can be changed out in the field easily, without re-positioning the remaining modules.
Modular ink jet printer system 10 is being implemented to successfully adjust the digital print equipment to the exact customer needs without having to have multiple single purpose machines. It will also provide for easy field upgrades for customers that find new products to print or require new or additional components.
In some embodiments, a base module or primary module can be used that is larger than other modules of the assembly, as it may contain most critical drive and print functions. The remaining modules or expansion modules can vary in size, depending on the design requirements for that specific module. All modules are designed to place operator functions in an ergonomic zone, limiting the overall height to a practical range.
Electrical, mechanical, piping, pneumatic, other machine utilities and signals are routed to the necessary modules using expandable cabinetry and expandable ducting. Very robust brackets and connecting bars will be utilized to ensure that backplanes of modules 12 being assembled stay truly planar on the base rail system.
|Cited Patent
|Filing date
|Publication date
|Jan 16, 1974
|Mar 11, 1975
|Pitney Bowes Inc
|Ink jet postage printing apparatus
|May 30, 1978
|Oct 28, 1980
|Xerox Corporation
|Modular laser printing system
|Mar 10, 1983
|Aug 14, 1984
|A. B. Dick Company
|Ink composition for ink jet printing
|Mar 9, 1983
|Jan 15, 1985
|Pitney Bowes Inc.
|Postage printing apparatus having a movable print head in a print drum
|Jun 1, 1987
|Feb 7, 1989
|Xerox Corporation
|Ink compositions for impact typewriter ribbons
|Apr 26, 1990
|Nov 26, 1991
|Mannesmann A.G.
|Expandable module frame for mounting printer and accessory modules
|Jun 27, 1990
|Apr 14, 1992
|Xaar Limited
|Jet printing ink compositions and methods
|Jan 28, 1991
|Oct 13, 1992
|Trident, Inc.
|High definition impulse ink jet in compositions
|Jan 11, 1991
|Nov 3, 1992
|Trident, Inc.
|Rapidly drying impulse ink jet ink compositions
|Aug 25, 1992
|May 3, 1994
|Sci Systems, Inc.
|Airline ticket printer with stepper motor for selectively engaging print head and platen
|Apr 15, 1993
|Dec 27, 1994
|Minolta Camera Kabushiki Kaisha
|Recording solution for ink jetting
|Sep 14, 1993
|Feb 28, 1995
|Videojet Systems International, Inc.
|Drop-on-demand ink composition with environmental advantages
|Aug 8, 1994
|Aug 22, 1995
|Videojet Systems International, Inc.
|High temperature jet printing ink
|Apr 21, 1993
|Nov 21, 1995
|Quad/Tech, Inc.
|Apparatus and method for addressing variable thickness signatures
|Apr 25, 1994
|Apr 23, 1996
|Videojet Systems, Inc.
|Ink jet composition for printing on textiles
|May 5, 1995
|Oct 15, 1996
|E. I. Du Pont De Nemours And Company
|Water-based silver-silver chloride compositions
|Dec 2, 1994
|Apr 1, 1997
|Illinois Superconductor Corporation
|Electromagnetic resonant filter comprising cylindrically curved split ring resonators
|Aug 14, 1995
|May 20, 1997
|Williamson Printing Corporation
|Combined lithographic/flexographic printing apparatus and process
|Jan 21, 1997
|Mar 10, 1998
|Xerox Corporation
|Charge generation layer containing mixture of terpolymer and copolymer
|Jun 12, 1995
|Apr 14, 1998
|Brother Kogyo Kabushiki Kaisha
|Jet printing ink and printing method using the ink
|Dec 12, 1994
|Jun 2, 1998
|Xerox Corporation
|Mounting arrangement for a raster output scanner
|Aug 27, 1997
|Dec 8, 1998
|Minnesota Mining And Manufacturing Company
|Thermal printing apparatus
|Mar 28, 1996
|Nov 16, 1999
|Rexam Industries Corp.
|Flexible composite surfacing film and method for producing same
|Apr 10, 1996
|Feb 1, 2000
|Rodi; Anton
|Printing press with replaceable units allowing for different methods of printing
|Jun 26, 1998
|Apr 11, 2000
|Mitsubishi Pencil Kabushiki Kaisha
|Ink composition for writing instrument
|Oct 6, 1998
|Sep 5, 2000
|3M Innovative Properties Company
|Piezo inkjet inks and methods for making and using same
|Apr 9, 1998
|Oct 3, 2000
|Seiko Epson Corporation
|Printing apparatus, printing method, and recording medium
|Apr 30, 1999
|May 15, 2001
|Macdermid Acumen, Inc.
|Ink composition and a method of making the ink composition
|Aug 24, 1999
|Jul 3, 2001
|Toshiba Tec Kabushiki Kaisha
|Color ink jet printer
|Jun 11, 1999
|Aug 21, 2001
|Kodak Polychrome Graphics Llc
|Surfactant-pretreated printing plate substrate, lithographic printing plate and method for production thereof
|Aug 4, 2000
|Dec 11, 2001
|Hitachi Koki Co., Ltd
|Print head having array of printing elements for printer
|Oct 30, 2000
|Feb 12, 2002
|Eastman Kodak Company
|Protective epoxy overcoat for imaging elements
|May 31, 2000
|Jul 2, 2002
|Rexam Graphics Inc.
|Glossy ink jet medium
|Jun 29, 2001
|Sep 3, 2002
|Hewlett-Packard Company
|Printing strategy for improved image quality and durability
|Jul 19, 2000
|Sep 24, 2002
|Mitsubishi Polyester Film Corporation
|Film for ink jet recording sheet
|Feb 23, 2000
|Feb 25, 2003
|Brian C. Ewert
|Variable image printing using inkjet printer
|Dec 20, 2000
|Mar 11, 2003
|Eastman Kodak Company
|Print masks for high speed ink jet printing
|Feb 18, 1999
|Mar 18, 2003
|Toshiba Tec Kabushiki Kaisha
|Driving method for recording head
|Mar 26, 1999
|Jun 10, 2003
|Spectra, Inc.
|Single-pass inkjet printing
|Apr 17, 2002
|Jul 1, 2003
|Hewlett-Packard Development Company, L.P.
|Preparations for ink-jet printing on common household surfaces
|Jul 16, 2001
|Jul 8, 2003
|Eastman Kodak Company
|Continuous ink-jet printing apparatus with pre-conditioned air flow
|Feb 9, 2001
|Jul 12, 2001
|Kellett Richard M.
|Ink jet fluid composition and ink jet printing using same
|Jun 22, 2001
|Mar 14, 2002
|Fox James E.
|Ink for inkjet printing that produces a durable image
|Mar 13, 2000
|Aug 15, 2002
|Chizuo Ozawa
|Recording medium printing apparatus
|May 13, 2002
|Dec 5, 2002
|Lin An-Chung Robert
|Colorless toner formulated to improve light fastness of ink jet ink prints
|Oct 30, 2001
|May 1, 2003
|Gunther Max S.
|Inkjet printing using pigmented and dye-based inks
|Jan 22, 2003
|Jul 31, 2003
|Senichi Yoshizawa
|Ink jet recording sheet
|May 14, 2003
|Nov 20, 2003
|Wellspring Trust
|High-speed, high-resolution color printing apparatus and method
|Apr 2, 2003
|Nov 27, 2003
|Baxter William R.S.
|Method and apparatus for creating an image on an article and printed article
|Dec 23, 2002
|Dec 4, 2003
|Ludwig Bret W.
|Ink jet receptive coating
|Sep 12, 2003
|Apr 29, 2004
|Fuji Photo Film Co., Ltd.
|Sheet for ink jet recording, ink for ink jet recording, manufacturing method of ink for ink jet recording, ink set for ink jet recording, and ink jet recording method
|Dec 20, 2002
|Jun 24, 2004
|Westvaco Corporation, A Corporation Of The State Of Delaware
|Polymer blend compositions
|Sep 15, 2003
|Sep 16, 2004
|Fuji Xerox Co., Ltd.
|Recording apparatus
|Apr 9, 2003
|Oct 14, 2004
|Milliken & Company
|Methods employed in solvent-based ink jet printing
|Dec 12, 2003
|Jun 16, 2005
|Forest Corporation
|Base printed with ink receptive medium
|Oct 25, 2004
|Sep 1, 2005
|Tom Look
|Laminated cards and methods of manufacture for secure applications
|Nov 3, 2005
|May 4, 2006
|Samsung Electronics Co., Ltd.
|Printing method and apparatus for an ink-jet printer having a wide printhead
|Oct 14, 2000
|Apr 25, 2002
|Tampoprint Gmbh
|Printing on to surfaces for decoration, uses ink jet printing in a single-stage combined with prior coating with a primer and/or subsequent covering with a protective varnish
|Apr 6, 1994
|Dec 14, 1994
|Taiyo Yuden Co., Ltd.
|Optical information medium and method for fabricating same
|May 25, 1999
|Dec 15, 1999
|Konica Corporation
|Line type ink-jet printer
|Sep 11, 2002
|Mar 19, 2003
|Toshiba Tec Kabushiki Kaisha
|Recording head and recording apparatus using the same
|Oct 22, 2002
|May 7, 2003
|Hewlett-Packard Company
|Ink compositions and methods of ink-jet printing on hydrophobic media
|Jan 15, 2002
|Dec 3, 2003
|Seiko Epson Corporation
|Oily ink composition for ink-jet recording, and ink-jet recording method
|Title not available
|Title not available
|Dec 21, 1999
|Jun 28, 2001
|Citizen Watch Co., Ltd.
|Ink receiving element and method for printing
|Jul 13, 2001
|Jan 24, 2002
|Genaissance Pharmaceuticals, Inc.
|Haplotypes of the mmp13 gene
|Jan 15, 2002
|Jul 18, 2002
|Seiko Epson Corporation
|Oily ink composition for ink-jet recording, and ink-jet recording method
|Feb 5, 2001
|Aug 15, 2002
|Avery Dennison Corporation
|Topcoat compositions, substrates containing a topcoat derived therefrom, and methods of preparing the same
|Sep 4, 2003
|Mar 18, 2004
|Canon Kabushiki Kaisha
|Image forming process and image forming apparatus
|Nov 6, 2003
|May 27, 2004
|Creo Il. Ltd.
|Using continuous spray inkjet system for accurately printing titanium oxide based inks
|U.S. Classification
|International Classification
|Cooperative Classification
|European Classification
|Sep 12, 2008
Owner name: ELECTRONICS FOR IMAGING, INC., CALIFORNIA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:EDWARDS, PAUL ANDREW;HENNESSY, JOHN;REEL/FRAME:021524/0152;SIGNING DATES FROM 20080820 TO 20080827
Owner name: ELECTRONICS FOR IMAGING, INC., CALIFORNIA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:EDWARDS, PAUL ANDREW;HENNESSY, JOHN;SIGNING DATES FROM 20080820 TO 20080827;REEL/FRAME:021524/0152
|Jul 8, 2015
|Fee payment
Year of fee payment: 4