Samun sa

A cikin aikin injiniya mai aminci, kalmar nan samuwa tana da ma'anoni masu zuwa:samuwa

• Matsayin da tsarin, tsarin ko kayan aiki ke cikin takamaiman yanayin aiki da alhakin aiki a farkon manufa, lokacin da aka kira manufa a wani ba a sani ba, watau bazuwar, lokaci.
• Halin yiwuwar wani abu zai yi aiki da gamsarwa a wani lokaci lokacin da aka yi amfani da shi a karkashin yanayin da aka bayyana a cikin kyakkyawan yanayin tallafi.

Yawancin tsarin samuwa na yau da kullun ana iya ƙayyade su a matsayin 99.98%, 99.999% ko 99.9996%. Sabanin, rashin samuwa, shine 1 minus samuwa.

Wakilin

MA sauki wakilC na samuwa (A) shine rabo na sa ran darajar uptime na tsarin zuwa jimlar da ake tsammani dabi'un sama da sauka lokaci (wanda ke haifar da "cikakken lokaci" C na lura taga)

$A={\frac {E[\mathrm {uptime} ]}{E[\mathrm {uptime} ]+E[\mathrm {downtime} ]}}={\frac {E[\mathrm {uptime} ]}{C}}$

WA daidaitattun don samuwa (A) shine rabo na Matsakaicin Lokaci don Rashin Nasara (MTTF) da Matsakaicin Lokacin Tsakanin Rashin Nasarawa (MTBF), ko

$A={\frac {MTTF}{MTTF+MTTR}}={\frac {MTTF}{MTBF}}$

Idan muka ayyana aikin matsayi

X (t)

{\displaystyle X (t) }

kamar yadda

$X(t)={\begin{cases}1,&{\text{sys functions at time }}t\\0,&{\text{maintenance}}\end{cases}}$

sA da haka, kasancewar A (t) a lokacin t > 0 ana wakilta ta

$A(t)=\Pr[X(t)=1]=E[X(t)].\,$

Dole ne a bayyana matsakaicin samuwa a kan wani lokaci na ainihin layin. Idan muka yi la'akari da wani abu mai mahimmanci

c > 0

{\displaystyle c>0}

, sa'an nan matsakaicin samuwa ana wakilta shi kamar yadda

$A_{c}={\frac {1}{c}}\int _{0}^{c}A(t)\,dt.$

Yankewa (ko daidaitaccen yanayin) ana wakilta shi da

$A=\lim _{c\rightarrow \infty }A_{c}.$

An kuma bayyana iyakance matsakaicin samuwa a kan wani lokaci

[ 0 , c ]

{\displaystyle [0,c]}

kamar yadda,

$A_{\infty }=\lim _{c\rightarrow \infty }A_{c}=\lim _{c\rightarrow \infty }{\frac {1}{c}}\int _{0}^{c}A(t)\,dt,\quad c>0.$

Samun shine yiwuwar cewa wani abu zai kasance a cikin yanayin aiki da alhakin aiki a farkon manufa lokacin da aka kira manufa a lokaci mara kyau, kuma an bayyana shi gabaɗaya a matsayin lokacin aiki da aka raba ta jimlar lokacin (lokacin aiki tare da lokacin aiki).

Jerin vs Abubuwan da ke cikin layi daya

jerin vs sassan layi daya

Bari mu ce wani bangare na jerin ya kunshi bangarorin A, B da C. Sa'an nan kuma wannan tsari ya shafi:

Samun sashi na jerin = (samun sashi A) x (samun bangare B) x (kasancewar bangare C)

Sabili da haka, haɗakar wadatar abubuwa da yawa a cikin jerin koyaushe ƙasa da wadatar abubuwan da ke cikin mutum.

A gefe guda, wannan tsari ya shafi sassan layi daya:

Samun sassan layi daya = 1 - (1 - kasancewar sashi A) X (1 - kasancewarsa na sashi B) X (1: kasancewar sashe C)

10 runduna, kowannensu yana da kashi 50% na samuwa. Amma idan an yi amfani da su a layi daya kuma sun kasa da kansu, za su iya samar da wadata mai yawa.

A cikin ma'ana, idan kuna da N sassan layi daya kowannensu yana da X, to:

Samun sassan layi daya = 1 - (1 - X) ^ N

Yin amfani da sassan layi daya na iya kara yawan wadatar tsarin gaba ɗaya. Misali idan kowane daga cikin rundunoninku yana da kashi 50% kawai, ta hanyar amfani da rundunonin 10 a layi daya, zaku iya samun 99.9023% samuwa.

Lura Lura cewa Redundancy ba koyaushe ke haifar da mafi girma samarwa ba. A zahiri, sake fasalin yana ƙaruwa rikice-rikice wanda ya rage kasancewa. A cewar Marc BroOKER, don amfani da Redundancy, tabbatar da cewa

redundancy ba koyaushe yana haifar da wadata mafi girma ba. A zahiri, redundancy yana ƙara rikitarwa wanda hakan ke rage wadata. A cewar Marc Brooker, don amfani da redundancy, tabbatar da cewa:

1. Kuna samun ci gaba mai kyau a cikin cikakkiyar tsarin ku
2. Abubuwan da ke cikinka sun kasa da kansu
3. Tsarinku na iya gano abubuwan da suka dace masu lafiya
4. Tsarinku na iya daidaitawa da kuma daidaitawa da abubuwan da ba su da amfani.

Hanyoyi da dabaru don samar da samfurin

Ana haɓaka Diagrams na Amincewa ko Nazarin Itace don lissafin kasancewar tsarin ko yanayin gazawar aiki a cikin tsarin ciki har da dalilai da yawa kamar:

• Misalai na amintacce
• Misalai masu kiyayewa
• Ka'idojin kiyayewa
• Rashin amfani
• Rashin nasarar da aka saba da shi
• Binciken ganewar asali
• Matsayin gyare-gyare
• Yanayin gyare-gyare
• Rashin cin nasara
• Gudanar da gwajin
• Lokaci na aiki / manufofi / jihohin tsarin
• Abubuwan da suka dace kamar; matakan ajiya a wurare daban-daban, lokutan sufuri, lokutan gyare-gyare a layin gyare-gine daban-daban.
• Rashin tabbas a cikin sigogi

Bugu da ƙari, waɗannan hanyoyin suna iya gano abubuwa masu mahimmanci da yanayin gazawar ko abubuwan da suka shafi kasancewar.

Ma'anar a cikin tsarin injiniya

Samun, asal_i (Ai) Da yiwuwar cewa wani abu zai yi aiki da gamsarwa a wani lokaci lokacin da aka yi amfani da shi a ƙarƙashin yanayin da aka bayyana a cikin kyakkyawan yanayin tallafi. Ya cire lokacin dabaru, jira ko lokacin gudanarwa, da kuma lokacin kiyayewa. Ya haɗa da lokacin gyarawa. Ana samun wadatar asali ne daga nazarin ƙirar injiniya:

1. Tasirin wani abu mai gyarawa (refurbishing / remanufacture ba gyara ba ne, amma maimakon maye gurbin) akan kasancewar tsarin, wanda yake aiki, daidai yake da lokaci tsakanin gazawar MTBF / (MTBF + yana nufin lokaci don gyara MTTR).
2. Tasirin wani abu daya / wanda ba za a iya gyarawa ba (za a iya gyara / sake yin shi) akan wadatar tsarin, wanda yake aiki, daidai yake da matsakaicin lokacin gazawar (MTTF) / (MTT F + matsakaicin lokaci don gyara MTTR).

Ya dogara ne akan adadi a ƙarƙashin ikon mai zanen.

Samun, wanda aka samu (Aa) Da yiwuwar cewa wani abu zai yi aiki da gamsarwa a wani lokaci lokacin da aka yi amfani da shi a ƙarƙashin yanayin da aka bayyana a cikin kyakkyawan yanayin tallafi (watau, cewa ma'aikata, kayan aiki, adadi, da dai sauransu suna nan take). Ya cire lokacin dabaru da jira ko lokacin gudanarwa. Ya haɗa da rigakafi mai aiki da gyaran gyare-gyare.

Kasancewa, mai aiki (Ao) Yiwuwar abu zai yi aiki mai gamsarwa a wani lokaci da aka ba da lokacin amfani da shi a cikin yanayin aiki na gaske ko na gaske. Ya haɗa da lokacin kayan aiki, lokacin shirye-shiryen, da jira ko lokacin gudanarwa, da duka na rigakafi da gyaran gyare-gyare. Wannan ƙimar tana daidai da ma'anar lokacin tsakanin gazawa ( MTBF ) an raba ta lokacin tsaka-tsaki tsakanin gazawar da ma'anar raguwa (MDT). Wannan ma'auni yana ƙaddamar da ma'anar samuwa ga abubuwan da masana dabaru da masu tsara manufa ke sarrafawa kamar yawa da kusancin kayan aiki, kayan aiki da ma'aikata zuwa kayan masarufi.

Dubi tsarin injiniya don ƙarin bayani

Misali na asali

Idan muna amfani da kayan aiki wanda ke da matsakaicin lokacin gazawar (MTTF) na shekaru 81.5 kuma matsakaicin lokaci don gyara (MTTR) na awa 1:

MTTF a cikin sa'o'i = 81.5 × 365 × 24 = 713940 (Wannan amintaccen ma'auni ne kuma sau da yawa yana da babban matakin rashin tabbas!)

Samun asali (Ai) = 713940 / (713940+1) = 713740 / 713941 = 99.999860%= 713940 / (713940+1) = 713940 / 713941 = 99.999860%

Rashin samuwa = 1 / 713940 = 0.000140%

Cutar saboda kayan aiki a cikin sa'o'i a kowace shekara = 1/rate = 1/MTTF = 0.01235 hours a kowace shekara.

Littattafai

An kafa samuwa sosai a cikin wallafe-wallafen samfurin stochastic da kuma ingantaccen kulawa. Barlow da Proschan [1975] sun bayyana kasancewar tsarin gyare-gyare a matsayin "mai yiwuwa tsarin yana aiki a wani lokaci da aka ƙayyade t. " Blanchard [1998] ya ba da ma'anar inganci na samuwa a matsayin "ma'auni na matakin tsarin da ke cikin yanayin aiki da kuma alhakin a farkon aikin lokacin da aka kira aikin a wani lokaci mara kyau". Wannan ma'anar ta fito ne daga MIL-STD-721. Lie, Hwang, da Tillman [1977] sun samar da cikakken bincike tare da rarraba tsarin samuwa.

Ana rarraba matakan samuwa ta hanyar ko dai lokacin sha'awa ko hanyoyin tsarin lokacin aiki. Idan lokacin sha'awa shine babban damuwa, muna la'akari da nan take, iyakancewa, matsakaici, da iyakance matsakaicin samuwa. An haɓaka ma'anar da aka ambata a sama a cikin Barlow da Proschan [1975], Lie, Hwang, da Tillman [1977], da Nachlas [1998]. Rarrabawar farko ta biyu don samuwa ya dogara da hanyoyin daban-daban don lokacin aiki kamar wadatar asali, samun wadata, da wadatar aiki. (Blanchard [1998], Lie, Hwang, da Tillman [1977]). Mi [1998] yana ba da wasu sakamakon kwatankwacin samuwa la'akari da wadatar asali.

Ana iya samun samuwa da aka yi la'akari da ƙirar ƙira a cikin Barlow da Proschan [1975] don samfuran maye gurbin, Fawzi da Hawkes [1991] don tsarin R-out-of-N tare da spares da gyare-gyare, Fawzi da Hawkes [1990] don jerin tsarin tare da maye gurbin da gyarawa, Iyer [1992] don gyaran gyaran gyare-gyaren da ba daidai ba [1992] Nau'in gyare-gyare na zamani, Murdoch 5. [1998, 1989] don samfuran kulawa na rigakafi, da Wang and Pham [1996] don ƙirar kulawa mara kyau. Wani cikakken littafin kwanan nan na Trivedi da Bobbio [2017].

Aikace-aikacen

Ana amfani da fa'idar samuwa sosai a aikin injiniyan wutar lantarki . Misali, Kamfanin Amintaccen Lantarki na Arewacin Amurka ya aiwatar da Tsarin Samar da Samun Samar da Bayanai a cikin 1982.

Dubi kuma

• Dogaro da shi
• Injiniyanci mai aminci
• Injiniyanci na tsaro
• Jerin halayen ingancin tsarin
• Matsayin tafiye-tafiye na ƙarya
• Kulawa ta hanyar yanayi
• Rahoton kuskure
• Samun yawa
• RAMS

Tushen

•  
• K. Trivedi da A. Bobbio, Amincewa da Samun Injiniya: Misali, Bincike da Aikace-aikace, Cambridge University Press, 2017.

Haɗin waje

• Amincewa da Abubuwan Gaskiya
• Amincewa da Tsarin
• Samun da Hanyoyi daban-daban don Ƙididdige shi
• Ta yaya za a bi da kuma inganta wadatar Fasaha?