{"id":367,"date":"2013-06-18T22:54:53","date_gmt":"2013-06-18T15:54:53","guid":{"rendered":"http:\/\/science-technology.vn\/?p=367"},"modified":"2013-06-21T10:58:49","modified_gmt":"2013-06-21T03:58:49","slug":"six-sigma","status":"publish","type":"post","link":"https:\/\/science-technology.vn\/?p=367","title":{"rendered":"Six Sigma"},"content":{"rendered":"

M\u1ed9t ng\u01b0\u1eddi qu\u1ea3n l\u00ed ph\u1ea7n m\u1ec1m vi\u1ebft cho t\u00f4i: \u201cCh\u00fang t\u00f4i mu\u1ed1n c\u1ea3i ti\u1ebfn ch\u1ea5t l\u01b0\u1ee3ng s\u1ea3n ph\u1ea9m v\u00e0 mu\u1ed1n d\u00f9ng ph\u01b0\u01a1ng ph\u00e1p Six Sigma. Ch\u00fang t\u00f4i \u0111\u00e3 nh\u1eadn \u0111\u01b0\u1ee3c v\u00e0i s\u00e1ch qu\u1ea3ng c\u00e1o v\u1ec1 ph\u01b0\u01a1ng ph\u00e1p n\u00e0y t\u1eeb c\u00e1c nh\u00e0 t\u01b0 v\u1ea5n nh\u01b0ng ch\u00fang t\u00f4i mu\u1ed1n ki\u1ec3m xem n\u00f3 l\u00e0m vi\u1ec7c t\u1ed1t th\u1ebf n\u00e0o \u1edf c\u00e1c c\u00f4ng ti kh\u00e1c tr\u01b0\u1edbc khi chi ti\u1ec1n. Xin th\u1ea7y l\u1eddi khuy\u00ean.\u201d<\/span><\/p>\n

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\u0110\u00e1p: Six Sigma l\u00e0 c\u00e1ch ti\u1ebfp c\u1eadn h\u1ec7 th\u1ed1ng \u0111\u1ec3 c\u1ea3i ti\u1ebfn k\u1ebft qu\u1ea3 c\u1ee7a qu\u00e1 tr\u00ecnh ch\u1ebf t\u1ea1o trong Motorola. Thu\u1eadt ng\u1eef n\u00e0y m\u00f4 t\u1ea3 cho c\u00e1ch m\u00f4 h\u00ecnh ho\u00e1 th\u1ed1ng k\u1ebf ch\u1ec9 ra n\u0103ng su\u1ea5t ch\u1ebf t\u1ea1o theo s\u1ed1 ph\u1ea7n tr\u0103m c\u1ee7a s\u1ea3n ph\u1ea9m kh\u00f4ng l\u1ed7i. M\u1ed9t qui tr\u00ecnh Six Sigma c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c mong \u0111\u1ee3i cho s\u1ea3n ph\u1ea9m kh\u00f4ng l\u1ed7i t\u1edbi 99.9%. V\u00e0o cu\u1ed1i nh\u1eefng n\u0103m 1980, Motorola \u0111\u1eb7t m\u1ee5c \u0111\u00edch v\u1ec1 “Six Sigma” cho m\u1ecdi ho\u1ea1t \u0111\u1ed9ng ch\u1ebf t\u1ea1o c\u1ee7a n\u00f3. \u0110i\u1ec1u quan tr\u1ecdng c\u1ea7n l\u01b0u \u00fd l\u00e0 \u0111\u00e2y l\u00e0 m\u1ee5c \u0111\u00edch h\u1ecd \u0111\u1eb7t ra, n\u00f3 kh\u00f4ng c\u00f3 ngh\u0129a m\u1ecdi th\u1ee9 h\u1ecd x\u00e2y d\u1ef1ng \u0111\u1ec1u \u0111\u00e3 \u0111\u1ea1t t\u1edbi m\u1ee9c ch\u1ea5t l\u01b0\u1ee3ng n\u00e0y nh\u01b0 ph\u1ea7n l\u1edbn m\u1ecdi ng\u01b0\u1eddi th\u01b0\u1eddng n\u00f3i t\u1edbi. M\u1eb7c d\u1ea7u Six Sigma l\u00e0 kh\u00e1i ni\u1ec7m r\u1ea5t t\u1ed1t cho c\u1ea3i ti\u1ebfn qui tr\u00ecnh trong ch\u1ebf t\u1ea1o nh\u01b0ng nhi\u1ec1u ng\u01b0\u1eddi th\u01b0\u1eddng “c\u1ee9 n\u00f3i” r\u1eb1ng h\u1ecd \u0111\u00e3 \u0111\u1ea1t t\u1edbi m\u1ee9c ch\u1ea5t l\u01b0\u1ee3ng n\u00e0y trong nhi\u1ec1u khu v\u1ef1c k\u1ec3 c\u1ea3 ph\u1ea7n m\u1ec1m.<\/p>\n

Six Sigma bao g\u1ed3m m\u1ed9t v\u00f2ng \u0111\u1eddi c\u1ea3i ti\u1ebfn c\u00f3 n\u0103m pha: X\u00e1c \u0111\u1ecbnh v\u1ea5n \u0111\u1ec1; \u0110o hi\u1ec7u n\u0103ng; Ph\u00e2n t\u00edch l\u1ed7 h\u1ed5ng gi\u1eefa hi\u1ec7u n\u0103ng hi\u1ec7n th\u1eddi v\u00e0 hi\u1ec7u n\u0103ng nh\u1eafm t\u1edbi; Th\u1ef1c hi\u1ec7n c\u1ea3i ti\u1ebfn; v\u00e0 Ki\u1ec3m so\u00e1t qui tr\u00ecnh (DMAIC). V\u00e0 nhi\u1ec1u k\u0129 thu\u1eadt ph\u00e2n t\u00edch th\u1ed1ng k\u00ea \u0111\u1ec3 ph\u00e2n t\u00edch d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c thu th\u1eadp trong pha \u0111o nh\u01b0 “S\u01a1 \u0111\u1ed3 ch\u1ea1y”, “Ph\u00e2n t\u00edch c\u0103n nguy\u00ean”, “Ki\u1ec3m so\u00e1t gi\u1edbi h\u1ea1n” v.v.<\/p>\n

V\u1ec1 l\u00ed thuy\u1ebft, n\u00f3 l\u00e0 logic v\u00e0 d\u1ec5 gi\u1ea3i th\u00edch. Trong th\u1ef1c t\u1ebf, th\u1ef1c hi\u1ec7n Six Sigma y\u00eau c\u1ea7u s\u1ef1 h\u1ed7 tr\u1ee3 m\u1ea1nh c\u1ee7a qu\u1ea3n l\u00ed, nhi\u1ec1u \u0111\u00e0o t\u1ea1o, v\u00e0 nhi\u1ec1u n\u1ed7 l\u1ef1c ngang qua m\u1ecdi m\u1ee9c qu\u1ea3n l\u00ed v\u00e0 c\u00f4ng nh\u00e2n. D\u1eef li\u1ec7u \u0111\u01b0\u1ee3c thu th\u1eadp cho ph\u00e2n t\u00edch ph\u1ea3i c\u00f3 ch\u1ea5t l\u01b0\u1ee3ng cao \u0111\u1ec3 nh\u1eadn di\u1ec7n khu v\u1ef1c c\u0103n nguy\u00ean cho c\u1ea3i ti\u1ebfn. Ch\u1eebng n\u00e0o c\u00f4ng ti c\u00f2n ch\u01b0a thi\u1ebft l\u1eadp t\u1ed1t qui tr\u00ecnh v\u00e0 c\u00f3 k\u1ec9 lu\u1eadt v\u1ec1 v\u0103n ho\u00e1 \u0111o v\u00e0 s\u1ea3n ph\u1ea9m ph\u1ea3i c\u00f3 ch\u1ea5t l\u01b0\u1ee3ng tuy\u1ec7t \u0111\u1ed1i cao nh\u01b0 trong y t\u1ebf, qu\u00e2n s\u1ef1, hay s\u1ea3n ph\u1ea9m h\u1ea1t nh\u00e2n n\u01a1i \u0111\u1ed9 ch\u00ednh x\u00e1c v\u00e0 an to\u00e0n l\u00e0 m\u1ea5u ch\u1ed1t, vi\u1ec7c \u00e1p d\u1ee5ng Six Sigma c\u00f3 th\u1ec3 qu\u00e1 m\u1ea1nh cho b\u1ea5t k\u00ec c\u00f4ng ti n\u00e0o v\u00e0 k\u1ebft th\u00fac trong th\u1ea5t b\u1ea1i.<\/p>\n

Theo kinh nghi\u1ec7m c\u1ee7a t\u00f4i, x\u00e1c \u0111\u1ecbnh v\u1ea5n \u0111\u1ec1 l\u00e0 d\u1ec5 nh\u01b0ng thu th\u1eadp d\u1eef li\u1ec7u v\u00e0 \u0111o hi\u1ec7u n\u0103ng qui tr\u00ecnh l\u00e0 kh\u00f4ng \u0111\u01a1n gi\u1ea3n. Ph\u00e2n t\u00edch k\u1ebft qu\u1ea3 c\u00f3 th\u1ec3 l\u00e0 v\u00f4 ngh\u0129a ch\u1eebng n\u00e0o b\u1ea1n ch\u01b0a c\u00f3 d\u1eef li\u1ec7u tuy\u1ec7t \u0111\u1ed1i ch\u00ednh x\u00e1c v\u00e0 d\u1eef li\u1ec7u \u0111\u1ee7 \u1ed5n \u0111\u1ecbnh m\u00e0 c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c \u0111\u1ecbnh c\u1ee1 xu\u1ed1ng \u0111\u1ed9 ch\u00ednh x\u00e1c nh\u1ea5t c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c. T\u1eeb kinh nghi\u1ec7m v\u1edbi CMMI, t\u00f4i ngh\u0129 n\u1ebfu c\u00f4ng ti c\u1ee7a b\u1ea1n KH\u00d4NG \u0111\u1ea1t t\u1edbi \u00edt nh\u1ea5t CMMI m\u1ee9c 5, Six Sigma kh\u00f4ng ph\u1ea3i l\u00e0 c\u00e1i g\u00ec \u0111\u00f3 b\u1ea1n c\u1ea7n th\u1eed. \u0110i\u1ec1u \u0111\u00f3 kh\u00f4ng c\u00f3 ngh\u0129a l\u00e0 t\u00f4i kh\u00f4ng th\u00edch kh\u00e1i ni\u1ec7m v\u1ec1 Six Sigma, t\u00f4i \u0111\u00e3 l\u00e0m vi\u1ec7c tr\u00ean kh\u00e1i ni\u1ec7m \u0111\u00f3 trong nhi\u1ec1u n\u0103m khi t\u00f4i c\u00f2n \u1edf Motorola nh\u01b0ng t\u1eeb quan \u0111i\u1ec3m th\u1ef1c h\u00e0nh, t\u1eebng ph\u01b0\u01a1ng ph\u00e1p c\u00f3 ch\u1ed7 c\u1ee7a n\u00f3, t\u00f4i tin Six Sigma l\u00e0 r\u1ea5t t\u1ed1t trong ch\u1ebf t\u1ea1o s\u1ea3n ph\u1ea9m b\u00e1n d\u1eabn n\u01a1i c\u1ea7n ph\u1ea3i kh\u00f4ng c\u00f3 l\u1ed7i n\u00e0o. Tuy nhi\u00ean \u00e1p d\u1ee5ng kh\u00e1i ni\u1ec7m n\u00e0y cho ph\u00e1t tri\u1ec3n ph\u1ea7n m\u1ec1m n\u01a1i c\u00e1c qui tr\u00ecnh kh\u00f4ng \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh r\u00f5; vi\u1ec7c thu th\u1eadp d\u1eef li\u1ec7u ch\u01b0a ch\u00edn mu\u1ed3i; d\u1eef li\u1ec7u l\u1ecbch s\u1eed kh\u00f4ng \u1ed5n \u0111\u1ecbnh hay kh\u00f4ng \u0111\u1ee7 ch\u00ednh x\u00e1c cho m\u00f4 h\u00ecnh ho\u00e1 th\u1ed1ng k\u1ebf c\u00f3 th\u1ec3 kh\u00f4ng ph\u1ea3i l\u00e0 \u00fd t\u01b0\u1edfng t\u1ed1t.<\/p>\n

T\u00f4i kh\u00f4ng khuy\u00ean \u00e1p d\u1ee5ng Six Sigma trong ph\u00e1t tri\u1ec3n ph\u1ea7n m\u1ec1m. \u0110\u1ec3 c\u1ea3i ti\u1ebfn ch\u1ea5t l\u01b0\u1ee3ng, c\u00f3 nh\u1eefng ph\u01b0\u01a1ng ph\u00e1p t\u1ed1t h\u01a1n \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf cho ph\u1ea7n m\u1ec1m \u0111\u00e3 t\u1ed3n t\u1ea1i nh\u01b0 gi\u00e1m \u0111\u1ecbnh ch\u00ednh th\u1ee9c (gi\u00e1m \u0111\u1ecbnh Fagan), PSP, TSP v.v.<\/p>\n

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—-English version—-<\/p>\n

 <\/p>\n

Six Sigma<\/p>\n

A software manager wrote to me: \u201cWe want to improve the quality of our products and want to use the Six Sigma method. We have received several brochures about this method from consultants but we want to check how well it works in other companies before spending our money. Please advice.\u201d<\/p>\n

Answer: Six Sigma is a systematic approach for improving the results of the manufacturing process in Motorola. The term describes a\u00a0statistical modeling that indicates the manufacturing yield or the percentage of defect-free products. A Six Sigma process can be expected to yield 99.9% of defect free products. In the late 1980s, Motorola set a goal of “Six Sigma” for all of its manufacturing operations. It is important to note that this was the goal that they set, it does not means everything they built have achieve this level of quality as most people often referred to. Although Six Sigma is a very good concept for process improvement in the manufacturing but many people often \u201cclaimed\u201d that they have achieved this level of quality in many areas including software.<\/p>\n

Six Sigma consists of an improvement life cycle that has five phases: Define problem; Measure performance; Analyze gaps between current performance and target performance; Implement improvements; and Control the process (DMAIC). And several statistical analysis techniques to analyze data collected in the measure phase such as \u201cRun charts\u201d, \u201cRoot cause analysis\u201d, \u201cControl limits\u201d etc.<\/p>\n

In theory, it is logical and easy to explain. In reality, implementing Six Sigma requires a strong management support, a lot of trainings, and a lot of efforts across all level of management and workers. The collected data for analysis must be of high quality to identify root cause area for improvement. Unless the company has well established process and have disciplined measurement culture and the products must be of absolute high quality such as in medical, military, or nuclear products where accuracy and safety are critical, the application of Six Sigma can be overwhelming for any company and often end up in failure.<\/p>\n

In my experience, defining the problem is easy but collecting data and measuring process performance are not that simple. The analysis of the results can be meaningless unless you have absolute accurate data and stable enough data that can be calibrated down to the most accuracy possible. From the experience with the CMMI, I think if your company has NOT reached at least CMMI level 5, Six Sigma is not something that you want to try. It does not mean I do not like the concept of Six Sigma, I worked on that for many years when I was at Motorola but from the practical point of view, each method has its place, I believe Sig Sigma is very good in the manufacturing of semi conducting products where a zero defect is needed. However applying this concept to software developments where processes are not well defined; data collection is not matured; historical data are not stable or accurate enough for statistical modeling may not be a good idea.<\/p>\n

I do not recommend applying Six Sigma in software development. To improve quality, there are better methods designed for software already exist such as Formal inspection (Fagan\u2019s inspection), PSP, TSP etc.<\/p>\n","protected":false},"excerpt":{"rendered":"

M\u1ed9t ng\u01b0\u1eddi qu\u1ea3n l\u00ed ph\u1ea7n m\u1ec1m vi\u1ebft cho t\u00f4i: \u201cCh\u00fang t\u00f4i mu\u1ed1n c\u1ea3i ti\u1ebfn ch\u1ea5t l\u01b0\u1ee3ng s\u1ea3n ph\u1ea9m v\u00e0 mu\u1ed1n d\u00f9ng ph\u01b0\u01a1ng ph\u00e1p Six Sigma. … <\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[27,24],"tags":[],"class_list":["post-367","post","type-post","status-publish","format-standard","hentry","category-tang-truong-nang-luc-to-chuc","category-quan-li-du-an"],"_links":{"self":[{"href":"https:\/\/science-technology.vn\/index.php?rest_route=\/wp\/v2\/posts\/367","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/science-technology.vn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/science-technology.vn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/science-technology.vn\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/science-technology.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=367"}],"version-history":[{"count":3,"href":"https:\/\/science-technology.vn\/index.php?rest_route=\/wp\/v2\/posts\/367\/revisions"}],"predecessor-version":[{"id":369,"href":"https:\/\/science-technology.vn\/index.php?rest_route=\/wp\/v2\/posts\/367\/revisions\/369"}],"wp:attachment":[{"href":"https:\/\/science-technology.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=367"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/science-technology.vn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=367"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/science-technology.vn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=367"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}