natgillin/translations-raw huggingface dataset:
a minimum of 82,5 mm forward of the defined bonnet rear reference line or forward of a wrap around distance of 1700 mm, whichever is most forward at the selected test point;
najmanj 82,5 mm pred referenčno črto zadnjega dela prednjega pokrova ali pred oklepajočo razdaljo 1700 mm, kar od tega je najbolj sprednji del na izbrani preskusni točki;
a minimum of 82,5 mm rearward of the bonnet leading edge reference line or rearward of a wrap around distance of 1000 mm whichever is more rearward at the selected test point.
najmanj 82,5 mm za referenčno črto prednjega roba prednjega pokrova ali za oklepajočo razdaljo 1000 mm, kar od tega je najbolj zadnji del na izbrani preskusni točki.
The selected test points for the adult headform impactor shall be
Izbrane preskusne točke za preskus trčenja z modelom udarne glave odraslega morajo biti:
a minimum of 82,5 mm forwards of the defined bonnet rear reference line or forward of a wrap around distance of 2100 mm, whichever is most forward at the selected test point;
najmanj 82,5 mm pred referenčno črto zadnjega dela prednjega pokrova ali pred oklepajočo razdaljo 2100 mm, kar od tega je najbolj sprednji del na izbranih preskusnih točkah;
a minimum of 82,5 mm rearward of the defined bonnet leading edge reference line or rearward of a wrap around distance of 1700 mm, whichever is most rearward at the selected test point.
najmanj 82,5 mm za referenčno črto prednjega roba prednjega pokrova ali za oklepajočo razdaljo 1700 mm, kar od tega je najbolj zadnji del na izbrani preskusni točki.
If a number of test positions have been selected and the test area remaining is too small to select another test position while maintaining the minimum spacing between tests, then less than nine tests may be performed.
Če je bilo določeno število preskusnih točk izbrano in je preostalo preskusno območje premajhno, da bi se lahko ob ohranjanju predpisanih najmanjših razdalj izbrala še ena preskusna točka, se lahko izvede manj kot devet preskusov.
However, the technical services conducting the tests shall perform as many tests as necessary to guarantee the compliance of the vehicle with the head protection criteria (HPC) limit values of 1000 for the HPC1000 impact zone and 1700 for the HPC1700 impact zone, especially in the points near to the borders between the two types of zones.
Vendar pa morajo tehnične službe, ki opravljajo preskuse, izvesti toliko preskusov, kolikor je potrebno za dokaz skladnosti vozila s kriteriji zaščite glave (HPC), ki za „območje udarca HPC1000“ določajo mejno vrednost 1000 in za „območje udarca HPC1700“ mejno vrednost 1700, in sicer zlasti v točkah v bližini mej med obema območjema.
Identification of HPC1000 and HPC1700 impact zones.
Določitev območij udarca HPC1000 in HPC1700.
The manufacturer shall identify the impact zones of the bonnet top where the head protection criterion (HPC) shall not exceed 1000 (HPC1000 zone) respectively 1700 (HPC1700 zone), in accordance with the requirements set out in point 3.5 of Annex I to Regulation (EC) No 78/2009.
Proizvajalec določi območja udarca zgornje površine prednjega pokrova, na katerih kriterij zaščite glave (HPC) ne sme presegati 1000 (območje HPC1000) ali 1700 (območje HPC1700), v skladu z zahtevami iz točke 3.5 Priloge I k Uredbi (ES) št. 78/2009.
Marking of HPC1000 and HPC1700 zones
Označevanje območij HPC1000 in HPC1700
Marking of the bonnet top impact area as well as the impact zones will be based on a drawing, supplied by the manufacturer, showing a view from a horizontal plane above the vehicle that is parallel to the plane on which the vehicle is standing.
Označitev preskusnega območja zgornje površine prednjega pokrova in območij udarca se opravi na osnovi risbe, ki jo dostavi proizvajalec, v vodoravni ravnini nad vozilom, ki je vzporedna z ravnino, na kateri stoji vozilo.
A sufficient number of x and y coordinates shall be supplied by the manufacturer to mark up the areas on the actual vehicle while considering the vehicle outer contour in the z direction. The areas of the HPC1000 and HPC1700 zones may each consist of several parts, with the number of these parts not being limited.
Proizvajalec mora podati zadostno število koordinat x in y za označitev območij na vozilu, pri čemer upošteva zunanji obris vozila v smeri z. Območji HPC1000 in HPC1700 sta lahko sestavljeni iz več delov, pri čemer število teh delov ni omejeno.
The calculation of the surface of the impact area as well as the surface areas of the impact zones shall be done on the basis of a projected bonnet when viewed from a horizontal plane parallel to the horizontal zero plane above the vehicle, on the basis of the drawing data supplied by the manufacturer.
Površina preskusnega območja ter površini območij udarca se izračunajo na podlagi projekcije pokrova motorja na vodoravno ravnino nad vozilom, vzporedno z ničelno vodoravno ravnino, na podlagi podatkov iz risbe proizvajalca.
The state of the vehicle or subsystem shall comply with the requirements of Chapter I. The stabilised temperature of the test apparatus and the vehicle or sub-system shall be 20 °C ± 4 °C.
Stanje vozila ali podsistema mora ustrezati zahtevam iz poglavja I. Ustaljena temperatura preskusne naprave in vozila ali podsistema mora biti 20 °C ± 4 °C.
The child/small adult and adult impactors to be used for the purposes of these tests shall be the ones as described in Sections 3 and 4 of Part V.
Modeli udarne glave otroka/majhnega odraslega in odraslega, ki se uporabljajo za namene teh preskusov, morajo biti skladni z opisom iz oddelkov 3 in 4 dela V.
The impactors shall be mounted, propelled and released as specified in points 2.1 and 2.2.
Modeli udarne glave se pritrdijo, poženejo in sprožijo, kakor je določeno v točkah 2.1 in 2.2.
The direction of impact shall be on a vertical longitudinal plane of the vehicle through the point to be tested.
Smer udarca je na navpični vzdolžni ravnini vozila skozi točko, ki se preskuša.
The angle of impact for tests with the child headform impactor shall be 50° ± 2° to the Ground Reference Level.
Za preskuse trčenja z modelom udarne glave otroka znaša kot udarca 50° ± 2° glede na referenčno raven tal.
The angle of impact for tests with the adult headform impactor shall be 65° ± 2° to the Ground Reference Level.
Za preskuse trčenja z modelom udarne glave odraslega znaša kot udarca 65° ± 2° glede na referenčno raven tal.
The impact velocity of the headform impactors when striking the bonnet top shall be 9,7 ± 0,2 m/s.
Hitrost udarne glave pri udarcu v zgornjo površino prednjega pokrova motorja mora biti 9,7 ±0,2 m/s.
BRAKE ASSIST SYSTEMS SPECIFICATION
SPECIFIKACIJA SISTEMOV POMOČI PRI ZAVIRANJU
The purpose of this Part is to ensure compliance with the test requirements for the verification of Brake Assist Systems, as required by Section 4 of Annex I to Regulation (EC) No 78/2009.
Namen tega dela je zagotoviti skladnost s preskusnimi zahtevami za preverjanje sistemov pomoči pri zaviranju (BAS – Brake Assist Systems), kakor se zahteva v oddelku 4 Priloge I k Uredbi (ES) št. 78/2009.
Performance characteristics for Category ‘A’ BAS systems
Značilnosti delovanja za sisteme BAS kategorije „A“.
When an emergency condition has been sensed by a relatively high pedal force, the additional pedal force to cause full cycling of the ABS shall be reduced compared to the pedal force required without the BAS in operation.
Ko so pri sorazmerno visoki sili na pedalu zaznane razmere zaviranja v sili, se dodatna sila na pedalu, da se sproži polno delovanje protiblokirnega zavornega sistema (ABS), zmanjša v primerjavi s silo na pedalu, ki je potrebna brez delovanja BAS.
Compliance with this requirement is demonstrated if the provisions of points 7.1 to 7.3 are met.
Skladnost s to zahtevo se dokaže, če so izpolnjene določbe iz točke 7.1 do 7.3.
Performance characteristics for Category ‘B’ and Category ‘C’ BAS systems.
Značilnosti delovanja za sisteme BAS kategorij „B“ in „C“.
When an emergency condition has been sensed, at least by a very fast application of the brake pedal, the BAS shall raise the pressure to deliver the maximum achievable braking rate or to cause full cycling of the ABS.
Ko so zaznane razmere zaviranja v sili, vsaj pri zelo hitri uporabi zavornega pedala, BAS dvigne tlak, da se zagotovi najvišja dosegljiva stopnja zaviranja ali da se sproži polno delovanje sistema ABS.
The requirement set out in this point shall be complied with if the provisions of points 8.1 to 8.3 are met.
Skladnost z zahtevo iz te točke se dokaže, če so izpolnjene določbe iz točke 8.1 do 8.3.
For the purposes of this Part, the following definitions shall apply:
V tem delu se uporabljajo naslednje opredelitve pojmov:
‘Category A Brake Assist System’ means a system which detects an emergency braking condition based on the brake pedal force applied by the driver;
„Sistem pomoči pri zaviranju kategorije A“ je sistem, ki zazna stanje zaviranja v sili na podlagi pritiska, s katerim voznik pritisne na zavorni pedal.
‘Category B Brake Assist System’ means a system which detects an emergency braking condition based on the brake pedal speed applied by the driver;
„Sistem pomoči pri zaviranju kategorije B“ je sistem, ki zazna stanje zaviranja v sili na podlagi hitrosti, s katero voznik pritisne na zavorni pedal.
‘Category C Brake Assist System’ means a system which detects an emergency braking condition based on multiple criteria, one of which shall be the rate at which the brake pedal is applied.
„Sistem pomoči pri zaviranju kategorije C“ je sistem, ki zazna stanje zaviranja v sili na podlagi več meril, med katerimi je tudi hitrost, s katero se uporabi zavorni pedal.
Whilst performing the tests set out in this Part, the following variables shall be measured:
Med izvajanjem preskusov, določenih v tem delu, se izmerijo naslednje spremenljivke:
Brake pedal force, Fp, applied at the centre of the brake pedal plate following a tangential arc to the brake pedal pivot;
sila na zavornem pedalu, Fp, ki v obliki tangentnega loka okoli tečaja zavornega pedala deluje na sredino površine zavornega pedala;
Vehicle longitudinal velocity, vx;
vzdolžna hitrost vozila vx;
Vehicle longitudinal acceleration, ax;
vzdolžni pospešek vozila ax;
Brake temperature, Td, measured on the surface of the braking path of the disc or drum of the front brakes;
temperatura zavor Td, izmerjena na zavorni površini zavornega koluta ali bobna prednjih zavor;
Brake pressure, P, where applicable;
zavorni tlak P, kadar je ustrezno;
Brake pedal travel, Sp, measured at the centre of the pedal plate or at a position on the pedal mechanism where the displacement is proportional to the displacement at the centre of the pedal plate allowing simple calibration of the measurement.
pot zavornega pedala Sp, izmerjena v sredini površine pedala ali na mestu mehanizma pedala, kjer je premik sorazmeren s premikom sredine površine pedala, kar omogoča enostavno kalibracijo meritve.
The variables listed in Section 3 shall be measured by means of appropriate transducers.
Spremenljivke iz oddelka 3 se izmerijo z ustreznimi senzorji.
Accuracy, operating ranges, filtering techniques, data processing and other requirements are described in ISO Standard 15037-1:2006.
Točnost meritev, merilna območja, tehnike filtriranja, obdelava podatkov in druge zahteve so opisane v standardu ISO 15037–1:2006.
Accuracy of pedal force and disc temperature measurements shall be as follows:
Meritve sile na pedalu in temperature koluta je treba opraviti z naslednjo točnostjo:
Typical operating range of the transducers
Tipično območje delovanja senzorjev
Recommended maximum recording errors
Priporočene najvišje napake pri beleženju
Pedal force
Sila na pedalu
0 to 2000 N
0 do 2000N
Brake disc temperature
Temperatura zavornih kolutov
Brake Pressure [1]
Zavorni tlak [1]
A sampling rate for data acquisition of at least 500 Hz is required.
Za odčitavanje podatkov je potrebna frekvenca vzorčenja vsaj 500 Hz.
Further details on analogue and digital data processing of the BAS test procedures are described in Appendix II to this Part.
Podrobnosti o analogni in digitalni obdelavi podatkov preskusnih postopkov BAS so opisane v dodatku II k temu delu.
Alternative measuring methods to those referred to above may be allowed, provided they demonstrate at least an equivalent level of precision.
Poleg navedenih metod so dovoljene tudi druge metode, če pokažejo vsaj enakovredno raven točnosti.
Test vehicle loading condition:
Pogoji obremenitve preskusnega vozila:
The vehicle shall be unladen.
Vozilo mora biti neobremenjeno.
There may be, in addition to the driver, a second person on the front seat who is responsible for noting the results of the tests.
Poleg voznika je lahko na sprednjem sedežu še ena oseba, ki je odgovorna za beleženje rezultatov preskusov.
The tests as described in Sections 7 and 8 shall be carried out from a starting test speed of 100 ± 2 km/h.
Preskusi, kakor so opisani v oddelkih 7 in 8, se izvedejo pri začetni hitrosti 100 ± 2 km/h.
The vehicle shall be driven at the test speed in a straight line.
Vozilo vozi s preskusno hitrostjo v ravni črti.
The average temperature of the front brakes shall be measured, in accordance with point 3.4 and recorded before each test and shall lie between 65 °C and 100 °C prior to any test.
Povprečna temperatura prednjih zavor se izmeri v skladu s točko 3.4 in zabeleži pred vsakim preskusom; pred vsakim preskusom mora znašati med 65 °C in 100 °C.
The braking tests shall be performed on a dry asphalt test track in accordance with ISO Standard 15037-1:1998.
Preskusi zaviranja se izvedejo na suhi asfaltni preskusni podlagi v skladu s standardom ISO 15037–1:1998.
For the tests, the reference time, t0, is defined as the moment when the brake pedal force reaches 20N.
Za preskuse se določi referenčni čas t0, kot trenutek, ko sila na zavornem pedalu doseže 20 N.
For vehicles equipped with a brake system assisted by an energy source, the applied pedal force necessary depends on the energy level that exists in the energy storage device.
Za vozila, opremljena s sistemom zaviranja, ki mu pomaga energetski vir, je uporabljena sila na pedalu nujno odvisna od energetske ravni, ki je v napravi za shranjevanje energije.
Therefore, sufficient energy level shall be ensured at the beginning of the test.
Zato je treba na začetku preskusa zagotoviti zadostno raven energije.
Assessment of the Presence of a Category ‘A’ BAS
Ocena prisotnosti BAS kategorije „A“
A Category ‘A’ BAS shall meet the test requirements contained in Sections 7.1 and 7.2.
BAS kategorije „A“ mora izpolnjevati preskusne zahteve iz oddelkov 7.1 in 7.2.
Test 1: Reference test to determine FABS and aABS
Preskus 1: Referenčni preskus za določitev FABS in aABS.
The reference values FABS and aABS shall be determined in accordance with the procedure described in Appendix I.
Referenčne vrednosti FABS in aABS se določijo v skladu s postopkom, opisanim v dodatku I.
Test 2: For activation of BAS
Preskus 2: za aktiviranje BAS.
Once an emergency braking condition has been detected, systems sensitive to pedal force shall show a significant increase in the ratio of:
Po zaznavi stanja zaviranja v sili morajo sistemi, občutljivi na silo na pedalu, pokazati znatno povečanje razmerja med:
brake line pressure to brake pedal force, where permitted by point 7.2.5 or
tlakom zavornega voda in silo na zavornem pedalu, kadar je to dovoljeno v skladu s točko 7.2.5., ali
vehicle deceleration to brake pedal force.
pojemkom vozila in silo na zavornem pedalu.
The performance requirements for a Category ‘A’ BAS are met if a specific brake application characteristic can be defined that exhibits a decrease of between 40 % and 80 % in required brake pedal force for (FABS — FT) compared to (FABSextrapolated — FT).
Zahteve glede zmogljivosti za BAS kategorije „A“ so izpolnjene, če je mogoče opredeliti posebno karakteristiko zaviranja, pri kateri je potrebna sila na pedalu za (FABS – FT) med 40 % do 80 % nižja kot (FABS ekstrapolirano – FT).
FT and aT are threshold force and threshold deceleration as shown in Figure 1.
FT in aT sta mejni vrednosti za silo in pojemek, kakor je prikazano na sliki 1.
The values of FT and aT shall be supplied to the Technical Service at the time of submission of the type-approval application.
Vrednosti za FT in aT se predložijo tehnični službi ob predložitvi vloge za homologacijo.
The value of aT shall be between 3,5m/s2 and 5,0m/s2.
Vrednost aT mora biti med 3,5 m/s2 in 5,0 m/s2.
A straight line is drawn from the origin through the point FT, aT (as shown in Figure 1a).
Iz izhodišča se skozi točko FT, aT nariše ravna črta (kakor je prikazano na sliki 1a).
The value of brake pedal force ‘F’, at the point of intersection between this line and a horizontal line defined by a = aABS, is defined as FABS, extrapolated:
Vrednost sile na zavornem pedalu „F“ na točki sečišča med to črto in vodoravno črto, opredeljeno z a = aABS, je opredeljena kot FABS, ekstrapolirana:
FABS, extrapolated
FABS, ekstrapolirano
As an alternative, which can be selected by the manufacturer, in the case of vehicles of GVM > 2500 kg of category N1, or M1 derived from those N1 vehicles, the pedal force figures for FT, FABS,min, FABS,max and FABS,extrapolated may be derived from the brake line pressure response characteristic instead of the vehicle deceleration characteristic.
Proizvajalec lahko kot alternativo za vozila kategorije N1 z bruto maso nad 2500 kg ali za vozila kategorije M1, ki so izvedena iz navedenih vozilih kategorije N1, vrednosti za silo na pedalu za FT, FABS,min, FABS,max in FABS,extrapolirano pridobi iz karakteristike odzivnega tlaka v zavornem vodu in ne karakteristike pojemka vozila.
This shall be measured as the brake pedal force is increasing.
To se izmeri med naraščanjem sile na zavornem pedalu.
The pressure, at which ABS cycling commences, shall be determined by making five tests from 100 ± 2 km/h in which the brake pedal is applied up to the level which produces ABS operation and the five pressures at which this occurs as determined from front wheel pressure records, shall be recorded and the mean value obtained as pabs.
Tlak, pri katerem začne delovati cikel ABS, se določi z izvedbo petih preskusov z začetno hitrostjo od 100 ± 2 km/h, pri katerih se zavorni pedal pritisne do stopnje, ki povzroči delovanje ABS, in se nato zabeleži ustrezna vrednost tlaka, ki ustreza navedbi tlaka na prednjih kolesih; dobljena srednja vrednost se označi kot Pabs.
The threshold pressure PT shall be stated by the manufacturer and correspond to a deceleration in the range of 2,5–4,5 m/s2.
Mejno vrednost praga tlaka PT določi proizvajalec in mora ustrezati pojemku v razponu 2,5–4,5 m/s2.
Figure 1b shall be constructed in the manner set out in point 7.2.4 but using line pressure measurements to define the parameters set out in point 7.2.5 above where:
Slika 1b se oblikuje tako, kot je določeno v točki 7.2.4., za določitev parametrov iz točke 7.2.5. pa je treba uporabiti meritve tlaka zavornega voda, pri čemer je:
Pedal force characteristic needed in order to achieve maximum deceleration with category ‘A’ BAS
Značilna sila na pedalu, ki je potrebna za doseganje najvišjega pojemka BAS kategorije „A“
Between 3,5 and 5,0 m/s2
Med 3,5 in 5,0 m/s2
Brake Pedal force, F
Zavorna sila pedala, F
Force change threshold
Mejna sprememba sile
The presence of a Category ‘A’ BAS is proven if
Prisotnost BAS kategorije „A“ se dokaže, če
where,
pri čemer je,
FT– Data evaluation
FT– Ovrednotenje podatkov
≤ FABS, extrapolated
≤ FABS, ekstrapolirana
≥ FABS, extrapolated
≥ FABS, ekstrapolirana
Assessment of the Presence of a Category ‘B’ BAS
Ocena prisotnosti BAS kategorije „B“
A Category ‘B’ BAS shall meet the test requirements contained within Sections 8.1 and 8.2 of this Part.
BAS kategorije „B“ mora izpolnjevati preskusne zahteve iz oddelkov 8.1 in 8.2.
The vehicle shall be driven in a straight line at the test starting speed specified in 6.1.
Vozilo vozi v ravni črti pri začetni hitrosti, določeni v točki 6.1.
The driver shall apply the brake pedal quickly according to Figure 2, simulating emergency braking so that BAS is activated and ABS is fully cycling.
Voznik pritisne na zavorni pedal hitro, v skladu s sliko 2, pri čemer simulira zasilno zaviranje, tako da se BAS aktivira, ABS pa je v polnem delovanju.
In order to activate BAS the brake pedal shall be applied as specified by the vehicle manufacturer.
Za aktiviranje BAS se zavorni pedal uporabi, kakor določi proizvajalec vozila.
The manufacturer shall notify the Technical Service of the required brake pedal input at the time of submission of the application for type-approval.
Proizvajalec o potrebni sili na pedalu obvesti tehnično službo, in sicer ob predložitvi vloge za homologacijo.
It shall be demonstrated to the satisfaction of the Technical Service that the BAS activates under the conditions specified by the manufacturer as follows:
Tehnični službi je treba predložiti zadostne dokaze, da se BAS aktivira pod pogoji, ki jih določi proizvajalec, na naslednji način:
For category B systems, definition of the brake pedal speed which shall be achieved in order to activate the Brake Assist System (e.g. pedal stroke speed 9 mm/s) during a given time interval).
za sisteme kategorije B, opredelitev hitrosti zavornega pedala, ki jo je treba doseči za aktiviranje sistema pomoči pri zaviranju (npr. hitrost premika pedala 9 mm/s) v določenem časovnem intervalu;
For category C systems, definition of the input variables affecting the decision to activate the Brake Assist System, the relationship between them and the pedal application required to activate the Brake Assist System for the tests described in this Part.
za sisteme kategorije C, opredelitev vhodnih spremenljivk, ki vplivajo na odločitev o aktiviranju BAS, razmerja med njimi in načina uporabe pedala, ki je potreben za aktiviranje BAS za preskuse, opisane v tem delu.
After t = t0 + 0,8 s and until the vehicle has slowed down to a speed of 15 km/h, the brake pedal force shall be maintained in a corridor between FABS, upper and FABS, lower.
Po času t = t0 + 0,8 s in dokler vozilo ne zmanjša hitrost na 15 km/h, se sila na zavornem pedalu ohranja v območju med FABS, zgornji in FABS, spodnji.
Where FABS, upper is 0,7 × FABS and FABS, lower is 0,5 × FABS.
Pri tem je FABS, zgornji 0,7 × FABS, spodnji pa 0,5 × FABS.
The requirements also are considered to be met if, after t = t0 + 0,8 s, the pedal force falls below FABS, lower provided the requirement of point 8.3 is fulfilled.
Zahteve so izpolnjene tudi, če po času t = t0+0,8 s sila na pedalu pade pod FABS, spodnja, pod pogojem, da je izpolnjena zahteva iz točke 8.3.
The presence of BAS category ‘B’ is proven if a mean deceleration of at least 0,85 × aABS is maintained from the time when t = t0 + 0,8 s to the time when the vehicle speed has been reduced to 15 km/h.
Prisotnost BAS kategorije „B“ se dokaže, če se od časa t = t0 + 0,8 s do časa, ko je bila hitrost vozila zmanjšana na 15 km/h, ohrani vsaj povprečni pojemek 0,85 × aABS.
Example of test 2 of a Category ‘B’ BAS system.
Primer preskusa 2 sistema BAS kategorije „B“
Brake pedal force F
sila na zavornem pedalu F
Deceleration ax
pojemek ax
Brake pedal force
zavorna sila pedala
FABS, super
FABS, zgornja
FABS, lower
FABS, spodnja
deceleration
pojemek
Initial pedal force
začetna sila na pedalu
+ 0,8 seconds
+ 0,8 sekund
Phase of panic pedal application
faza paničnega pritiska na pedal
Phase of BAS-evaluation (ending at speed of 15 km/h)
faza ocene – BAS (konec pri hitrosti 15 km/h)
Assessment of the Presence of a Category ‘C’ BAS.
Ocena prisotnosti BAS kategorije „C“
A Category ‘C’ BAS shall meet the test requirements of points 8.2 and 8.3
BAS kategorije „C“ mora izpolnjevati preskusne zahteve iz oddelkov 8.2 in 8.3.
A Category ‘C’ BAS shall meet the requirements of point 8.3.
BAS kategorije „C“ mora izpolnjevati zahteve iz točke 8.3.
Method for Determination of FABS and aABS
Metoda za določitev FABS in aABS