EPI Manual Codes

Search Tips - May 2000

What are Electrical Patents Index Manual Codes (EPI MAnual Codes) ?
If you are carrying out subject searches in Derwent World Patents Index (Derwent WPI), Derwent's Manual Codes are a very useful extra tool to have in your toolbox. Derwent developed these codes - one system for chemistry, one for electronics/electrical engineering - to enable you to search in the most convenient and accurate way for topics which often prove difficult to retrieve using other methods. Chemical Patents Manual Codes (CPI Manual Codes) are only available to Derwent subscribers; codes in the electronics/electrical engineering field (the EPI Manual Codes system) are available to everybody.

It is the EPI Manual Codes which we are going to look at in detail here.

First, we will explain what the codes are and how they fit into the overall structure of Derwent World Patents Index (Derwent WPI); next, we will discuss the similarities and differences between Derwent Manual Codes and the International Patent Classification (IPC); finally we will explain how to find the right codes for your search.

At the end of this Tip you will find search examples on each of the hosts (Dialog, Questel.Orbit and STN).

What does "EPI" stand for? How does the system work?
"EPI" stands for Electrical Patents Index. This is one of the three file segments which make up Derwent WPI, the others being CPI (Chemical Patents Index) and EngPI (Engineering Patents Index). Every invention in Derwent WPI falls into one - or sometimes more than one - of these categories.

Within each of these file segments, inventions are assigned to different Derwent Classifications - again, one or more according to their subject matter. The letters of the alphabet are used, with some gaps to allow for future expansion. Everything in the EPI file segment is classified using letters S to X. These broad classifications are very useful if you need a quick way to cover a broad subject area; the whole field of domestic electrical appliances, for example, could be covered by searching Derwent Class X27. They can also help you solve the problem of ambiguous search terms; incorporating X27 into a search on microwaves would ensure that you covered only domestic microwave ovens and not other applications of microwave technology. They are also very useful in online statistical analyses using RANK, MEMSORT and ANALYSE - for example in identifying a competitor's key areas of activity. A handy guide to the complete Derwent Classification, for all subject areas, is available free-of-charge on request.

Each Derwent Classification is only the broadest level of the full Manual Code hierarchy. X27, the domestic appliances classification used in our examples above, splits into garden appliances, cooking appliances, cleaning appliances, etc - and each of these divides into further levels of detail. There are nearly 9000 EPI Manual Codes altogether.

Why use EPI Manual Codes?
There are many occasions when words alone will not be sufficient to define your search topic. It may be that the appropriate words can have several different meanings in different contexts, or that there are too many synonyms or too many different ways of describing the subject. It may even be that you are not familiar enough with the technology to be confident in your ability to construct an adequate search strategy. These are the occasions when Manual Codes can help you. Consider, for example, the subject of cash-dispensing machines (ATMs). This would be difficult to search adequately using words alone, especially since there are so many aspects of the subject to cover. You can solve the problem using Manual Codes. T05-L03 covers the topic in one go - and you can even specify whether it is cash dispensing (T05-L03A5) or cash-depositing (T05-L03A1) that particularly interests you.

What is the difference between EPI Manual Codes and the International Patent Classification (IPC)?
Overall, Derwent Manual Codes and IPCs should be regarded as complementary; there will be some occasions when Manual Codes bring much better results and there will be other occasion when IPCs are more appropriate. There are parts of the EPI Manual Codes system which are very closely related to the IPC, but in general it is structured in a different way. Depending on the subject matter of your search, it is usually beneficial to consider using both classification systems to obtain the best results. Here is a comparison:

• The IPC covers all technologies; EPI Manual Codes cover electronics/electrical engineering and related subject areas.
• The IPC is applied differently by different patent offices and inconsistencies can arise; Manual Codes are assigned consistently by teams of subject experts at Derwent.
• The IPC may be assigned to different levels by different patent offices; Derwent staff always assign most specific Manual Code possible.
• New editions of IPC are brought into use at different times by different patent offices; new Manual Codes have always been introduced at the start of a production year.
• The hierarchical position of a particular classification within the IPC is not always clear from the number of characters; EPI Manual Codes have a well-defined hierarchy (ie an extra character always means a finer subdivision).
• The IPC is usually assigned for the main aspect of invention only; Manual Codes are assigned for the invention per se and also for significant applications and examples of its use.

What do EPI Manual Codes look like?
EPI Manual Codes always have the same format. Here is a typical hierarchy, showing the progression from the W01 Derwent Classification to the detailed W01-C02B7A Manual Code:

You can search at any of these levels - but do remember that if you want to include all the narrower levels in your search, you must truncate your search term. For example, if you search W01-C you will only retrieve the relatively small number of records which have been coded at the generic Telephony level (ie inventions of very broad scope); you will not retrieve inventions which have been assigned more specific codes. In order to cover the whole of telephony, you must truncate:

To search a specific Manual Code, enter it just as it is displayed:

How do I find the right code for my search?
There are several different methods:

• Use the EPI Manual Codes Manual: consult the subject index, IPC concordance or familiar sections within the classification itself.
• Carry out a rough preliminary search then use an inexpensive format (28 on Dialog, TICO on Questel.Orbit, TI TRIAL on STN) to check the Manual Codes in the records you have found.
• Carry out the most accurate preliminary search you can then use statistical analysis (Rank, Memsort or Analyse) to identify the most common Manual Codes within the set of records you have retrieved.
• On STN, an online thesaurus is available (see search example below).
• Contact the Derwent Customer Services Help Desk and, if necessary, communicate directly with a coder.

Whichever method you use to find the right code for your search, make sure you check the exact scope of the code and the date it was introduced; if a code was only introduced in 1992, a search using that code will over cover the period from 1992 onwards! The EPI Manual Codes Manual will give you guidance and will also suggest suitable alternatives.

Using EPI Manual Codes on Dialog: Search Example
Our topic is earthquake prediction and our aim is to retrieve as much as possible on this topic. This would be a difficult search to tackle using words - there is no single precise way to describe this subject - and there are no suitable IPCs. However, Derwent Manual Codes can probably help us. We begin with a rough word search, then we display a few records - to check that we are retrieving the right kind of information and also to get a preliminary idea of which Manual Codes have been applied to the records that are of interest to us. Having established that our search is fairly accurate, we can then use RANK to find out which Manual Code is the one that has been most commonly applied to these records. Having checked the definition and scope of the Manual Codes we have identified, we can now carry out a much more effective search.

Begin searching in Derwent World Patents Index (File 351):

? b 351

Carry out a rough word search ("(w)" means that search terms are adjacent to each other in the specified order; "(2n)" means that there can be up to 2 words in between the search terms and that the search terms can appear in any order):

? s earthquake? or earth(w)quake?

? s predict? or forecast?

? s s1(2n)s2

Display a couple of records in an inexpensive format to check relevance and obtain a preliminary indication of appropriate Manual Codes:

? t 3/28/30-31

  3/28/30

DIALOG(R)File 351:DERWENT WPI

(c) 2002 Derwent Info Ltd. All rts. reserv.



011843745    **Image available**

WPI Acc No: 98-260655/199823

XRPX Acc No: N98-205486

  Seismic activity earthquake predictor - has 

  dielectric receiving precursor seismic 

  electromagnetic waveforms.

Number of Countries: 076  Number of Patents: 003

Title Terms: SEISMIC; ACTIVE; EARTHQUAKE; PREDICT; 

  DIELECTRIC; RECEIVE; PRECURSOR; SEISMIC; 

  ELECTROMAGNET; WAVEFORM

Derwent Class: S03

International Patent Class (Main): G01V-003/12

International Patent Class (Additional): G01R-029/00; 

  G01V-001/16; G01V-003/16; G01V-011/00

File Segment: EPI

Manual Codes (EPI/S-X): S03-C02X; S03-C05

 3/28/31

DIALOG(R)File 351:DERWENT WPI

(c) 2002 Derwent Info Ltd. All rts. reserv.



011844745    **Image available**

WPI Acc No: 98-261655/199823

Related WPI Acc No: 98-261656

XRAM Acc No: C98-081359

XRPX Acc No: N98-206202

  Measuring electrical parameters of soil for 

  earthquake prediction - can determine strong 

  variations of the vertical gradient of the 

  electrical field of the soil associated with 

  the incoming earthquakes

Number of Countries: 021  Number of Patents: 003

Title Terms: MEASURE; ELECTRIC; PARAMETER; SOIL; 

  EARTHQUAKE; PREDICT; CAN; DETERMINE; STRONG; 

  VARIATION; VERTICAL; GRADIENT; ELECTRIC; FIELD; 

  SOIL; ASSOCIATE; INCOMING; EARTHQUAKE

Derwent Class: A85; S03

International Patent Class (Main): G01V-003/08

International Patent Class (Additional): G01R-029/00; 

  G01V-001/00; G01V-003/38; G08C-017/00

File Segment: CPI; EPI

Manual Codes (CPI/A-N): A09-A03; A12-E13

Manual Codes (EPI/S-X): S03-C02B; S03-C05

Polymer Indexing (PS):

  <01>

  *001* 018; R00232 G1650 G1649 D01 D19 D18 D31 D50 

        D76 D86 F08 F07; H0000; P1127 P1105 H0293 

        D01 D19 D18 F07

  *002* 018; ND01; Q9999 Q7874; Q9999 Q7476 Q7330; 

        K9483-R; K9676-R; K9416; K9905

 

Use RANK to find out which Manual Code appears most frequently in this set of records:

? rank mc
DIALOG RANK Results
-------------------------------
RANK: S3/1-193 Field: MC= File(s): 351
(Rank fields found in 172 records - - 118 unique terms) Page 1 of 15

Search the Manual Code for earthquake prediction: S03-C05:

? s mc=s03-c05
S4 286 MC=S03-C05

? s s3 or s4
S5 411 S3 OR S4

What has the Manual Code search brought us that we would not have found with our initial word search?

? s s4 not s3
L6 218 S4 NOT S3

? t 6/26/4,12,44,199

The Manual Code has enabled us to carry out a much more accurate search - and has even retrieved records that we would have missed with our initial word search.

Using EPI Manual Codes on Questel.Orbit: Search Example
Our topic is earthquake prediction and our aim is to retrieve as much as possible on this topic. This would be a difficult search to tackle using words - there is no single precise way to describe this subject - and there are no suitable IPCs. However, Derwent Manual Codes can probably help us. We begin with a rough word search, then we display a few records - to check that we are retrieving the right kind of information and also to get a preliminary idea of which Manual Codes have been applied to the records that are of interest to us. Having established that our search is fairly accurate, we can then use MEMSORT (or GET) to find out which Manual Code is the one that has been most commonly applied to these records. Having checked the definition and scope of the Manual Codes we have identified, we can now carry out a much more effective search.

Begin searching in Derwent World Patents Index (Derwent WPI):

file dwpi

Carry out a rough word search ("2d" means that there can be up to 2 words in between our search terms and that the search terms can appear in any order):

1 - earthquake+ or earth quake+
* * SS 1: Results 10818

2 - predict+ or forecast+
* * SS 2: Results 21246

3 - 1 2d 2
* * SS 3: Results 193

Display a couple of records in an inexpensive format to check relevance and obtain a preliminary indication of appropriate Manual Codes:

li tico 30-31

  30/193 WPIL - (C) Derwent

  AN  - 1998-260655 [23]

  XP  - N1998-205486

  DC  - S03

  TI  - Seismic activity earthquake predictor 

- has dielectric receiving precursor seismic 

electromagnetic waveforms.

  IC  - G01V-003/12 G01R-029/00 G01V-001/16 

  G01V-003/16 G01V-011/00

  MC  - EPI:  S03-C02X S03-C05

  NP  - 3

  NC  - 76

  31/193 WPIL - (C) Derwent

  AN  - 1998-261655 [23]

  XR  - 1998-261656

  XA  - C1998-081359

  XP  - N1998-206202

  DC  - A85 S03

  TI  - Measuring electrical parameters of soil for 

        earthquake prediction - can determine strong 

        variations of the vertical gradient of the

        electrical field of the soil associated with 

        the incoming earthquakes

  IC  - G01V-003/08 G01R-029/00 G01V-001/00 G01V-003/38 

        G08C-017/00

  MC  - CPI:  A09-A03 A12-E13

      - EPI:  S03-C02B S03-C05

  PI01- [001] 018; R00232 G1650 G1649 D01 D19 D18 D31 

        D50 D76 D86 F08 F07;

        H0000; P1127 P1105 H0293 D01 D19 D18 F07

[002] 018; ND01; Q9999 Q7874; Q9999 Q7476 Q7330; 

K9483-R; K9676-R; K9416; K9905

  NP  - 3

  NC  - 21

  UA  - 1998-23

Use MEMSORT to find out which Manual Code appears most frequently in this set of records:

mems ss 3 1-193 /mc
Total number of terms extracted: 558
Number of terms now in MEM2: 123

li mems
Memory is of type MEMSORT (statistical analysis)

Search the Manual Code for earthquake prediction: S03-C05:

4 - *mems 2 /mc
* * SS 4: Results 286

5 - 3 or 4
* * SS 5: Results 411

What has the Manual Code search brought us that we would not have found with our initial word search?

6 - 4 not 3
* * SS 6: Results 218

li ti 4,12,44,199

The Manual Code has enabled us to carry out a much more accurate search - and has even retrieved records that we would have missed with our initial word search.

Using EPI Manual Codes on STN: Search Example
Our topic is earthquake prediction and our aim is to retrieve as much as possible on this topic. This would be a difficult search to tackle using words - there is no single precise way to describe this subject - and there are no suitable IPCs. However, Derwent Manual Codes can probably help us. We begin with a rough word search, then we display a few records - to check that we are retrieving the right kind of information and also to get a preliminary idea of which Manual Codes have been applied to the records that are of interest to us. Having established that our search is fairly accurate, we can then use ANALYSE to find out which Manual Code is the one that has been most commonly applied to these records. The next step is to check the definition in STN's online thesaurus. Finally, we repeat the search - this time using the Manual Code.

Begin searching in Derwent World Patents Index (WPINDEX/WPIDS/WPIX):

=> file wpindex

Carry out a rough word search ("2a" means that there can be up to 2 words in between our search terms and that the search terms can appear in any order):

=> s earthquake? or earth quake?

=> s predict? or forecast?

=> s l1 (2a) l2

Display a few titles free-of-charge to check that this search is performing as expected:

=> d scan

Display a couple of records in an inexpensive format to check relevance and obtain a preliminary indication of appropriate Manual Codes:

=> d ti trial 30-31

L3   ANSWER 30 OF 193  WPINDEX  COPYRIGHT 2002 Derwent 

     INFORMATION LTD  

TI   Seismic activity earthquake predictor - has 

     dielectric receiving precursor seismic 

     electromagnetic waveforms..

AN   1998-260655 [23]   WPINDEX

DNN  N1998-205486

TT   TT: SEISMIC ACTIVE EARTHQUAKE PREDICT DIELECTRIC 

         RECEIVE PRECURSOR SEISMIC ELECTROMAGNET WAVEFORM.

DC   S03

IC   ICM  G01V-003-12

     ICS  G01R-029-00; G01V-001-16; G01V-003-16; G01V-011-00

MC   EPI: S03-C02X; S03-C05

PNC  3

CYC  76

L3   ANSWER 31 OF 193  WPINDEX  COPYRIGHT 2002 Derwent 

     INFORMATION LTD  

TI   Measuring electrical parameters of soil for 

     earthquake prediction - can determine strong 

     variations of the vertical gradient of the 

     electrical field of the soil associated with the 

     incoming earthquakes.

AN   1998-261655 [23]   WPINDEX

CR   1998-261656 [23] 

DNN  N1998-206202       DNC C1998-081359

TT   TT: MEASURE ELECTRIC PARAMETER SOIL EARTHQUAKE 

         PREDICT CAN DETERMINE STRONG VARIATION VERTICAL 

         GRADIENT ELECTRIC FIELD SOIL ASSOCIATE INCOMING 

         EARTHQUAKE.

DC   A85 S03

IC   ICM  G01V-003-08

     ICS  G01R-029-00; G01V-001-00; G01V-003-38; G08C-017-00

MC   CPI: A09-A03; A12-E13

     EPI: S03-C02B; S03-C05

PNC  3

CYC  21

Use ANALYSE to find out which Manual Code appears most frequently in this set of records:

=> analyse
ENTER ANSWER SET OR ANALYZE L# OR (L3):.
ENTER ANSWER NUMBER OR RANGE (1-):.
ENTER DISPLAY CODE (TI) OR ?:mc
L4 ANALYZE L3 1- MC : 121 TERMS

=> d
L4 ANALYZE L3 1- MC : 121 TERMS

Check STN's online thesaurus of Manual Codes to find out more about S03-C05:

=> e s03-c05+all/mc

******END***

Search the Manual Code for earthquake prediction: S03-C05:

=> s s03-c05/mc
S03-C05 EARTHQUAKE PREDICTION

=> s l3 or l5

What has the Manual Code search brought us that we would not have found with our initial word search?

=> s l5 not l3

=> d scan

The Manual Code has enabled us to carry out a much more accurate search - and has even retrieved records that we would have missed with our initial word search.

Further assistance please contact your local Derwent Help Desk.