Abstract:
To provide a reproduction method for enabling an automatic selection and reproduction of a music data suitable for a user&#39;s preference during the reproduction, for reproducing a contents data given with an attribute data, and having the steps of: reproducing a plurality of the contents data in a predetermined pattern successively; monitoring an execution of a predetermined input operation during reproducing the contents data; specifying an attribute data common to the plurality of the contents data, to which the input operation is not executed during the reproduction, when a number of the input operations exceeds a predetermined value; and reproducing a contents data given with the common attribute data.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS  
       [0001]     The present invention contains subject matter related to Japanese Patent Application JP 2005-74664 filed in the Japanese Patent Office on Mar. 16, 2005, the entire contents of which being incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a reproduction method and a reproduction apparatus for selecting and reproducing a contents data successively, and a recording medium.  
         [0004]     2. Description of the Related Art  
         [0005]     Recently, due to improving a large capacity and a small size of a hard disk drive (HDD) or other recording medium and a compression technology of a music data (audio data), an enormous number of the music data is able to be stored into the recording medium in a portable reproduction apparatus, a personal computer, or other electronic device.  
         [0006]     Such electronic device for example is provided with a function of automatically selecting and reproducing the music data stored into the HDD (referred to Japanese Unexamined Patent Application (Kokai) No. 2004-54023, for example).  
       SUMMARY OF THE INVENTION  
       [0007]     In the electronic device described above, however, a lot of the music data in which a user has not interested is also stored into the HDD, so, when the device automatically reproduces the enormous number of the music data stored into the HDD, the music data in which the user has not interested is also reproduced frequently.  
         [0008]     The present invention is to provide a reproduction method and a reproduction apparatus enabling an automatic selection and reproduction of a contents data suitable for a user&#39;s preference.  
         [0009]     According to an embodiment of the present invention, there is provided a reproduction method for reproducing a contents data given with an attribute data, the method having the steps of: reproducing a plurality of the contents data in a predetermined pattern successively; monitoring an execution of a predetermined input operation during reproducing the contents data; specifying an attribute data common to the plurality of the contents data, to which the input operation is not executed during the reproduction, when a number of the input operations exceeds a predetermined value; and reproducing a contents data given with the common attribute data.  
         [0010]     According to an embodiment of the present invention, there is provided a reproduction apparatus reproducing a contents data given with an attribute data, the apparatus having: a reproduction unit reproducing a plurality of the contents data successively; an operation unit inputting a predetermined input operation; a control unit monitoring the input operation of the operation means during reproducing the contents data, specifying an attribute data common to a plurality of the contents data, to which the input operation is not executed during the reproduction, when the number of the input operations exceeds a predetermined value, and reproducing the contents data given with the common attribute data.  
         [0011]     According to an embodiment of the present invention, there is provided a recording medium used to a reproduction apparatus reproducing a contents data given with an attribute data, the medium of recording data for: reproducing a plurality of the contents data in a predetermined pattern successively; monitoring an execution of a predetermined input operation during reproducing the contents data; specifying an attribute data common to the plurality of the contents data, to which the input operation is not executed during the reproduction, when a number of the input operations exceeds a predetermined value; and reproducing the contents data given with the common attribute data.  
         [0012]     According to a reproduction method, a reproduction apparatus, and a recording medium in embodiments of the present invention, it is able to automatically select a contents data suitable for a user&#39;s preference for a reproduction. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     The above and other features of embodiments of the present invention will be apparent in more detail with reference to the accompanying drawings, in which:  
         [0014]      FIG. 1  is a schematic view illustrating a configuration of an audio reproduction apparatus according to an embodiment of the present invention;  
         [0015]      FIG. 2  is a view for illustrating an attribute and an attribute item of a music data stored into an HDD shown in  FIG. 1 ;  
         [0016]      FIG. 3  is a view for illustrating a headphone shown in  FIG. 1 ;  
         [0017]      FIG. 4  is a flowchart for illustrating a first automatic reproduction operation of the audio reproduction apparatus shown in  FIG. 1 ;  
         [0018]      FIG. 5  is a view for illustrating an example of the automatic reproduction operation shown in  FIG. 4 ;  
         [0019]      FIG. 6  is a view for illustrating a group defined by the audio reproduction apparatus shown in  FIG. 1 ;  
         [0020]      FIG. 7  is a view for illustrating a second automatic reproduction operation of the audio reproduction apparatus shown in  FIG. 1 ;  
         [0021]      FIG. 8  is a view following  FIG. 7  and for illustrating the second automatic reproduction operation of the audio reproduction apparatus shown in  FIG. 1 ;  
         [0022]      FIG. 9  is a view for illustrating other example of a group according to an embodiment of the present invention; and  
         [0023]      FIG. 10  is a view for illustrating other example of a group according to an embodiment of the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0024]     Preferred embodiments of an audio reproduction apparatus (a contents reproduction apparatus) according to the present invention will be described in more detail with reference to the accompanying drawings.  
         [0025]     Note that, a music data will be applied as an example of a contents data in the present embodiment.  
         [0026]      FIG. 1  is a schematic view illustrating a configuration of an audio reproduction apparatus  1  according to an embodiment of the present invention.  
         [0027]     (Audio Reproduction Apparatus  1 )  
         [0028]     As shown in  FIG. 1 , the audio reproduction apparatus  1  for example has a universal serial bus (USB) interface  11 , a synchronous DRAM (SDRAM)  12 , a hard disk drive (HDD)  13 , a liquid crystal display (LCD) panel  14 , an input device  15 , a flash memory  16 , a central processing unit (CPU)  17 , and a wireless interface  21 .  
         [0029]     The USB interface  11 , the SDRAM  12 , the HDD  13 , the flash memory  16 , the CPU  17 , and the wireless interface  21  for example are connected via a data line  10 .  
         [0030]     The USB interface  11  is connected to a personal computer  3  and performs with the personal computer  3  an input and output operation of data.  
         [0031]     The SDRAM  12  temporary stores a data related to a processing of the CPU  17 .  
         [0032]     The HDD  13  stores a compressed music data.  
         [0033]     The music data is written from the personal computer  3  through the USB interface  11  into the HDD  13 .  
         [0034]     The HDD  13  for example has a storage capacity of 20 GB and is capable of storing the music data for about 10 thousand tracks (700 compact disk&#39;s worth of data) compressed by for example adaptive transform acoustic coding (ATRAC)  3 .  
         [0035]     Each track&#39;s worth of the music data stored into the HDD  13  (hereinafter, referred to a music data, for simplification) is given with an attribute (an attribute data) related to an attribute items, such as a file name data, an artist data, an album data, a music title data, a genre data, a music composer data, a released year data, a file production time data, and a device transfer time data as shown in  FIG. 2 , which are described in an attribute management table data PTABLE.  
         [0036]     In the present embodiment, the attribute data is not limited to a belonged ID3 tag and may be applied with a data designating a uniqueness of a contents data. For example, the attribute data may be designated with a tempo of a music as the attribute for example.  
         [0037]     The attribute management table data PTABLE for example is stored into the SDRAM  12  shown in  FIG. 1 , and is suitably updated by the CPU  17 .  
         [0038]     The LCD panel  14  displays various screens by the CPU  17 .  
         [0039]     Main screens displayed on the LCD panel  14  are for example a music selection screen, a setting screen, and a reproduction screen, which are respectively replaced (transited) in response to a user&#39;s key operation.  
         [0040]     The input device  15  is an operation unit such as a button for designating by a user a reproduction instruction, a reproduction stop instruction, a forward reproduction, a reverse reproduction, a skip (SKIP), a back skip (BSKIP), and a reproduction mode.  
         [0041]     In the present embodiment, as the above reproduction mode, a shuffle mode for randomly selecting and reproducing a plurality of the music data is defined for example.  
         [0042]     The flash memory  16  for example stores a program PRG in which an operation of the CPU  17  is defined.  
         [0043]     The CPU  17  controls an operation of the audio reproduction apparatus  1  based on the program PRG read out from the flash memory  16 , namely the CPU  17  performs a processing described in the present embodiment.  
         [0044]     The CPU  17  reads out the selected music data from the HDD  13  and decodes the same, and outputs the resultant to the wireless interface  21 .  
         [0045]     In the present embodiment, the CPU  17  defines a single or a plurality of group to which the music data belongs in the respective music data stored in the HDD  13 .  
         [0046]     The CPU  17  for example defines a plurality of the group based on the attribute data to the music data stored in the HDD  13  based on the attribute item and the attribute shown in  FIG. 2 , and stores the data into the SDRAM  12 .  
         [0047]     The CPU  17 , as later description, updates the above group when a predetermined condition is fulfilled, and updates the data stored in the SDRAM  12  in response to the above update.  
         [0048]     In the present embodiment, the CPU  17  for example defines as the above group a newly-arrived group including as a contents a music data transferred from the personal computer  3  to the HDD  13  during a predetermined period, a group including as a contents a music data of the same artist or album, and a group including as a contents a music data of the same genre, released year, or keyword.  
         [0049]     Note that, in the present embodiment, a group defined based on an attribute of date or other time factors is also referred to a time group.  
         [0050]     The wireless interface  21  transmits to the headphone  31  by electromagnetic waves the decoded music data input from the CPU  17 .  
         [0051]     (Headphone  31 )  
         [0052]     The headphone  31 , as shown in  FIG. 3 , for example has a wireless interface  33 , an audio output circuit  34 , a speaker  35 , and an operation unit group  36 .  
         [0053]     A data transmission among the wireless interface  33 , the audio output circuit  34 , and the operation unit group  36  is performed via a data line  32 .  
         [0054]     The wireless interface  33  receives by wireless signal the decoded music data transmitted by the wireless interface  21  of the audio reproduction apparatus  1  shown in  FIG. 1 , and outputs the same to the audio output circuit  34 .  
         [0055]     The audio output circuit  34  outputs to the speaker  35  an audio signal corresponding to the music data input from the wireless interface  33 .  
         [0056]     The speaker  35  has a left speaker and a right speaker, and outputs the audio signal input from the audio output circuit  34 .  
         [0057]     The operation unit group  36  for example has a volume operation unit  37 , a forward reverse (FW·RV) operation unit  38 , and a SKIP·BSKIP operation unit  39 .  
         [0058]     The volume operation unit  37  is used for controlling a volume of sound output from the speaker  35 .  
         [0059]     The forward reverse operation unit  38  is used for designating the forward reproduction or the reverse production.  
         [0060]     The SKIP·BSKIP operation unit  39  is used for designating a music skip or a music back skip.  
         [0061]     Blow, an automatic music selection operation based on a processing of the CPU  17  of the audio reproduction apparatus  1  shown in  FIG. 1  will be described.  
       FIRST OPERATION EXAMPLE  
       [0062]      FIG. 4  is a flowchart for illustrating a first automatic reproduction operation of the audio reproduction apparatus  1  shown in  FIG. 1 .  
         [0063]     Step ST 11   
         [0064]     The CPU  17  shown in  FIG. 1  monitors a SKIP operation signal input via the wireless interface  21  based on an operation of the SKIP·BSKIP operation unit  39  shown in  FIG. 3 , and judges whether or not an input pattern of a SKIP instruction fulfills a predetermined condition.  
         [0065]     The condition is for example a condition where a predetermined number of the SKIP instructions are input during a fullshuffled-pattern reproduction, or a condition where an input frequency of the SKIP instruction exceeds a predetermined reference value. The condition is for example defined to satisfy a user, who loses interest in the fullshuffled-pattern reproduction.  
         [0066]     In the present embodiment, the CPU  17  randomly selects and reproduces the entire music data stored in the HDD  13  or a music data determined in advance during the fullshuffled-pattern reproduction.  
         [0067]     The CPU  17  for example judges that the SKIP instruction is input when only predetermined ratio (for example, quarter) in the music is reproduced or a portion giving a deep impression to a person in the music is not reproduced after starting the reproduction of the music data.  
         [0068]     The CPU  17  judges that the SKIP instruction is not input to the reproducing music data when a back SKIP instruction is input.  
         [0069]     Step ST 12   
         [0070]     The CPU  17  for example compares an attribute data PRP of a plurality of the music data (the music data listened by a user), to which the SKIP instruction is not input, among a plurality of the music data of which a reproduction is started just before judging that the SKIP instruction fulfills the input condition at step ST 11 , and specifies a common attribute data and an attribute item data of the attribute data.  
         [0071]     When the common attribute data is a predetermined artist, the attribute item data is artist.  
         [0072]     Step ST 13   
         [0073]     When the CPU  17  judges that for example the attributes was specified at step ST 12 , it proceeds to step ST 14 , otherwise, when judging it is not, it proceeds to step ST 15 .  
         [0074]     Step ST 14   
         [0075]     The CPU  17  selects a group corresponding to the attribute indicated by the specified attribute data, in an attribute item indicated by the attribute item data specified at step  12 .  
         [0076]     The group for example includes as a contents a plurality of the music data indicating the same attribute in a predetermined attribute item.  
         [0077]     Step ST 15   
         [0078]     The CPU  17  selects in a predetermined reference an attribute item different from the attribute item used for selecting the group to be reproduced, and selects in a predetermined reference an attribute in the selected attribute item.  
         [0079]     The CPU  17  selects the attribute item and the attribute randomly or based on a priority given to the group for example.  
         [0080]     Then the CPU  17  selects the group corresponding to the selected attribute.  
         [0081]     Step ST 16   
         [0082]     The CPU  17  designates the group selected at step ST 14  or step ST 15  as a subject to be reproduced.  
         [0083]     Step ST 17   
         [0084]     The CPU  17  selects in the shuffled pattern a plurality of the music data belonging to the group designated at step ST 16 , reads out the selected music data from the HDD  13 , and decodes the same.  
         [0085]     The CPU  17  outputs the decoded music data to the wireless interface  21 , which transmits to the headphone  31  by wireless signal the music data input from the CPU  17 .  
         [0086]     The headphone  31  receives the above music data by the speaker  35 , and outputs an audio signal of the music data through the audio output circuit  34  to the speaker  35 .  
         [0087]      FIG. 5  is a view for illustrating a first automatic music selection operation of the audio reproduction apparatus  1  shown in  FIG. 1 .  
         [0088]     As shown in  FIG. 5 , the CPU  17  shown in  FIG. 1  for example selects the music data in the fullshuffled pattern, and reproduces the music data [ 1 ], [ 2 ], [ 3 ] and [ 4 ] successively.  
         [0089]     The CPU  17  receives a SKIP instruction by an operation of the SKIP·BSKIP operation unit  39  shown in  FIG. 3  during reproducing the music data [ 1 ] and [ 3 ], and judges whether or not the SKIP instruction fulfills an input pattern condition determined in advance (step ST 11  in  FIG. 4 ).  
         [0090]     The condition for example is a condition where a predetermined number of the SKIP instructions are input during the fullshuffled-pattern reproduction.  
         [0091]     When judging the above condition is fulfilled, the CPU  17  compares an attribute data of the reproduced music data to which the SKIP instruction is not executed during the fullshuffled-pattern reproduction, and specifies a common attribute data (step ST 12  in  FIG. 4 ).  
         [0092]     In the case illustrated in  FIG. 5  for example, the CPU  17  compares the attribute data of the music data [ 2 ] and [ 4 ], and specifies for example an artist AR 4  as a common attribute data.  
         [0093]     The CPU  17  selects a group (AR 4 ) including as a content the specified artist AR 4  (step ST 14  in  FIG. 4 ), designates the same as a subject to be reproduced (step ST 16  in  FIG. 4 ), and starts the shuffled reproduction by applying a group G (AR 4 ) shown in  FIG. 6  as the subject.  
         [0094]     Namely, the CPU  17  reads out from the HDD  13  the music data given with the specified common attribute data, and reproduces the same subsequent to a reproduction of the music data [ 4 ].  
         [0095]     In an example illustrated in  FIG. 5 , the music data [ 5 ] to [ 11 ] of the artist AR 4  is read out from the HDD  13  and reproduced.  
         [0096]     As shown in  FIG. 5 , each in the successively reproduced music data [ 10 ] and [ 11 ], when the SKIP instruction is input, the CPU  17  randomly selects artists except for the artist AR 4  from the artist of a classification item (step ST 16  in  FIG. 4 ).  
         [0097]     As shown in  FIG. 5 , for example, the CPU  17  selects an artist AR 5 .  
         [0098]     The CPU  17  selects a music data of the randomly selected artist in the shuffled pattern and reproduces the same (step ST 17  in  FIG. 4 ).  
         [0099]     Then, the CPU  17  receives the SKIP instruction by an operation of the SKIP·BSKIP operation unit  39  shown in  FIG. 3  during reproducing the music data [ 12 ] and [ 14 ], and judges whether or not the SKIP instruction fulfills the input pattern condition determined in advance.  
         [0100]     The condition is for example a condition where a predetermined number of the SKIP instructions are input during reproducing the music data of a predetermined artist.  
         [0101]     When judging the condition is fulfilled, the SKIP·BSKIP operation unit  39  selects the attribute items except for the artist, selects successively the music data of the attribute randomly selected in the selected attribute item, and reproduces the same.  
         [0102]     In the example illustrated in  FIG. 5 , the CPU  17  successively reads out from the HDD  13  the music data for example where a genre is “pop”, and reproduces the same.  
       SECOND OPERATION EXAMPLE  
       [0103]      FIG. 7  and  FIG. 8  are flowcharts for illustrating a second automatic reproduction operation of the audio reproduction apparatus  1  shown in  FIG. 1 .  
         [0104]     The present operation example is also an operation example in the shuffled reproduction.  
         [0105]     Step ST 21   
         [0106]     The CPU  17  shown in  FIG. 1  monitors an operation signal from the input device  15  shown in  FIG. 1  and an operation signal from the headphone  31  through the wireless interface  21 , and, when judging some operation signal is input, proceeds to step ST 22 .  
         [0107]     Step ST 22   
         [0108]     The CPU  17  performs a standby operation when the operation signal input at step ST 11  is a PAUSE short press action, or performs a power-off operation and then returns to step ST 21  when the operation signal is a PAUSE long press action.  
         [0109]     Step ST 23   
         [0110]     When judging that the entire music data in the designated group is selected and reproduced as a subject to be shuffle-reproduced, the CPU  17  proceeds to step ST 24 , otherwise, when judging it is not, proceeds to step ST 25 .  
         [0111]     Step ST 24   
         [0112]     The CPU  17  designates the following group as a subject to be reproduced.  
         [0113]     In this case, the CPU  17  designates a group corresponding to other undesignated attribute in the attribute item used for the previous designation.  
         [0114]     The CPU  17  may designate a group having the highest propriety in the undesignated groups based on the priority given to the group.  
         [0115]     Step ST 25   
         [0116]     The CPU  17  judges whether or not the SKIP instruction is input by the operation of the SKIP·BSKIP operation unit  39  shown in  FIG. 3 , based on the operation signal input from the wireless interface  21 .  
         [0117]     When judging that the SKIP instruction is input, the CPU  17  specifies a reproduction ratio data S(s) indicating that how much ratio the reproducing music data is reproduced at a timing where the above SKIP instruction is input, based on the operation signal.  
         [0118]     The CPU  17  judges whether or not the specified reproduction ratio data S(s) exceeds a predetermined threshold R.  
         [0119]     When judging that the data S(s) exceeds the threshold R, the CPU  17  proceeds to step ST 26 , otherwise, when judging that it does not, it returns to step ST 21 .  
         [0120]     Step ST 26   
         [0121]     The CPU  17  adds “ 1 ” into the number of skips in the reproducing group.  
         [0122]     The CPU  17  adds “ 1 ” into a data K(n) indicating the number of skips in the past of the music data reproducing when the SKIP instruction is input.  
         [0123]     Step ST 27   
         [0124]     The CPU  17  judges whether or not “K(n)/K(s)&gt;Ns” is formed based on a data K(s) indicating the number of reproductions in the past of the music data reproducing when the SKIP instruction is input, the data K(n) generated at step ST 26 , and the predetermined threshold Ns, and proceeds to step ST 28  when judging it is formed, otherwise it proceeds to step ST 29  when judging it is not.  
         [0125]     Step ST 28   
         [0126]     The CPU  17  transmits the reproducing music data from the designating group to a low priority group (a predetermined group) determined in advance.  
         [0127]     The CPU  17  lowers a selection priority for the low priority group compared with other groups, or designates the group as a subject to be unselected in a group selection.  
         [0128]     Step ST 29   
         [0129]     When judging that “n” is less than the maximum number of skips in the group, the CPU  17  proceeds to step ST 31 , otherwise it proceeds to step ST 30  when judging it is not.  
         [0130]     Step ST 30   
         [0131]     The CPU  17  sets a priority of the designating group at the lowest position.  
         [0132]     The CPU  17  selects and designates a subsequent group having the highest priority, and performs a shuffled-reproduction of the group to be subjected.  
         [0133]     The CPU  17  initializes “n” to be 0.  
         [0134]     Step ST 31   
         [0135]     The CPU  17  judges whether or not a current time displayed by a timer in the audio reproduction apparatus  1  and a time indicated by the attribute data corresponding to a plurality of group hold in advance are matched, and proceeds to step ST 32  when judging they are matched, otherwise it returns to step ST 21  when judging they are not.  
         [0136]     The time may be applied with for example Christmas Day, New Year&#39;s Day, and a user&#39;s birthday.  
         [0137]     Step ST 32   
         [0138]     The CPU  17  designates a group corresponding to the attribute data judged that the times are matched at step ST 31 , and performs the shuffled-reproduction of the group to be subjected.  
         [0139]     Note that, the group allocated with the attribute data indicating a time described above may be possible to be a lower priority group if a frequency of the SKIP instruction increases in the same way as other groups.  
         [0140]     As described above, according to the audio reproduction apparatus  1 , when the frequency of the SKIP instruction exceeds a reference during reproducing in a predetermined reproduction mode, a common attribute of the reproduced music data to which an effective SKIP instruction is not input is specified and the music data of the specified attribute is changed as a subject to be reproduced.  
         [0141]     Namely, according to the audio reproduction apparatus  1 , the apparatus learns an attribute of the music data suitable for a user&#39;s preference based on a user&#39;s SKIP instruction, and is able to automatically select the music data suitable for the user&#39;s preference and reproduce the same.  
         [0142]     According to the audio reproduction apparatus  1 , a group is defined based on the attribute of the music data and the change operation is performed by applying the group as a unit, so various groups suitable for the user&#39;s preference are defined, consequently, an automatic reproduction suitable for the same can be performed, and a processing load of the apparatus along an automatic music selection can be reduced.  
         [0143]     According to the audio reproduction apparatus  1 , the time group is defined based on a keyword and a released date of the music data, so a reproduction of the music data suitable for a season can be realized.  
         [0144]     The present invention is not limited the above embodiment.  
         [0145]     For example, the CPU  17  may perform a processing of step ST 31  shown in  FIG. 8  once, not every time, when reaching the processing of step ST 31  at the predetermined number of times.  
         [0146]     The CPU  17  may define as the time group in step ST 32  for example a group (G) ( 80 &#39;s) including as a contents a music data released in  80 &#39;s as shown in  FIG. 9 .  
         [0147]     The CPU  17  as shown in  FIG. 10  may define a group G (night) including as a contents the music data where the genre are “J-pop” and “pop” and a group G (morning) including as a contents the music group where the genre is “classical”, and select the group G (morning) at a predetermined condition in the forenoon and the group G (night) at a predetermined condition at night based on the attribute data corresponding to the current time data displayed by the timer and the groups (morning) and (night).  
         [0148]     In the above embodiment, while the case is described that the CPU  17  selects and reproduces a plurality of the music data belonging to the selected group successively in the shuffled pattern, the music data may be selected and reproduced in the selected group for example successively in a predetermined order (an order from the beginning of a group list toward the end).  
         [0149]     The CPU  17  may collect a music data where the frequency of the skip instruction is few (a predetermined frequency or less) to form a new play list (group), and manage the formed play list in the same way as other play lists.  
         [0150]     In the above embodiment, while the case is described that the audio reproduction apparatus  1  selects and decodes a music to form a music data, which is transmitted to the headphone  31 , a server at home having the same function as the audio reproduction apparatus  1  may be used instead of using the audio reproduction apparatus  1  and a client (for example, a personal computer) provided with a speaker may be used instead of using the headphone  31 .  
         [0151]     Further, a server on internet may be used instead of using the audio reproduction apparatus  1  and a personal computer provided with a speaker may be used instead of using the headphone  31 .  
         [0152]     The present invention can be applied to a data processing system for selecting and reproducing the music data successively.  
         [0153]     It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors in so far as they are within scope of the appeared claims or the equivalents thereof.