Intro: G C
G                      C
Dia hanya dia di duniaku
G                    C
Dia hanya dia di mataku
Am                  D
Dunia terasa telah menghilang
Am               D
Tanpa ada dia di hidupku
G                                C
Sungguh sebuah tanya yang terindah
G                            C
Bagaimana dia merengkuh sadarku
Am                     D
Tak perlu ku bermimpi yang indah
Am                D
Karena ada dia di hidupku
Chorus:
G
Ku ingin dia yang sempurna
Em
Untuk diriku yang biasa
Am              C
Ku ingin hatinya ku ingin cintanya
Am                 D
Ku ingin semua yang ada pada dirinya
G
Ku hanya manusia biasa
Em
Tuhan bantu ku tuk berubah
Am               C
Tuk miliki dia, tuk bahagiakannya
Am                D
Tuk menjadi seorang yang sempurna untuk dia
C  G D/F# Em
Am C D
overtone:
A
Ku ingin dia yang sempurna
F#m
Untuk diriku yang biasa
Bm                  D
Ku ingin hatinya ku ingin cintanya
Bm                 E
Ku ingin semua yang ada pada dirinya
A
Ku hanya manusia biasa
F#m
Tuhan bantu ku tuk berubah
Bm              D
Tuk miliki dia tuk bahagiakannya
Bm                 E
Tuk menjadi seorang yang sempurna
A
untuk dia
outro: A

EM7 Dm7 AM7 B

EM7            C#m7
You did it again
AM7
You did hurt my heart
B/G#
I don’t know how many times

EM7                          C#m7
You… I don’t know what to say
AM7
You’ve made me so desperately in love
B
and now you let me down

C#m7
You said you’d never lie again
G#m
You said this time would be so right
AM7                               B
But then I found you were lying there by her side

EM7                     C#m7
You.. You turn my whole life so blue
AM7                B
Drowning me so deep, I just can reach myself again
EM7                C#m7
You.. Successfully tore my heart
DM7
Now it’s only pieces
Am7
Nothing left but pieces of you

[interlude] EM7 C#m7 DM7 AM7 B 2x

EM7                        C#m7
You frustated me with this love
AM7
I’ve been trying to understand
B/G#
You know i’m trying i’m trying

EM7                        C#m7
You.. I don’t know what to say
AM7
You’ve made me so desperately in love
B
And now you let me down

Pengertian HIV

HIV merupakan singkatan dari 'Human Immunodeficiency Virus'. HIV adalah suatu virus yang dapat menyebabkan penyakit AIDS. Virus ini menyerang manusia dan menyerang sistem kekebalan (imunitas) tubuh, sehingga tubuh menjadi lemah dalam melawan infeksi. Dengan kata lain, kehadiran virus ini dalam tubuh akan menyebabkan defisiensi (kekurangan) sistem imun.

Atau HIV merupakan retrovirus yang menjangkiti sel-sel sistem kekebalan tubuh manusia (terutama CD4 positive T-sel dan macrophages– komponen-komponen utama sistem kekebalan sel), dan menghancurkan atau mengganggu fungsinya. Infeksi virus ini mengakibatkan terjadinya penurunan sistem kekebalan yang terus-menerus, yang akan mengakibatkan defisiensi kekebalan tubuh.

Sistem kekebalan dianggap defisien ketika sistem tersebut tidak dapat lagi menjalankan fungsinya memerangi infeksi dan penyakit-penyakit. Orang yang kekebalan tubuhnya defisien (Immunodeficient) menjadi lebih rentan terhadap berbagai ragam infeksi, yang sebagian besar jarang menjangkiti orang yang tidak mengalami defisiensi kekebalan. Penyakit-penyakit yang berkaitan dengan defisiensi kekebalan yang parah dikenal sebagai "infeksi oportunistik" karena infeksi-infeksi tersebut memanfaatkan sistem kekebalan tubuh yang melemah.

Pengertian AIDS

Definisi AIDS adalah singkatan dari 'Acquired Immunodeficiency Syndrome / Acquired Immune Deficiency Syndrome' yang menggambarkan berbagai gejala dan infeksi yang terkait dengan menurunnya sistem kekebalan tubuh. Infeksi HIV telah ditahbiskan sebagai penyebab AIDS. Tingkat HIV dalam tubuh dan timbulnya berbagai infeksi tertentu merupakan indikator bahwa infeksi HIV telah berkembang menjadi AIDS.

Seberapa cepat HIV bisa berkembang menjadi AIDS ?

Lamanya dapat bervariasi dari satu individu dengan individu yang lain. Dengan gaya hidup sehat, jarak waktu antara infeksi HIV dan menjadi sakit karena AIDS dapat berkisar antara 10-15 tahun, kadang-kadang bahkan lebih lama. Terapi antiretroviral dapat memperlambat perkembangan AIDS dengan menurunkan jumlah virus (viral load) dalam tubuh yang terinfeksi.

Demikianlah penjelasan singkat mengenai definisi atau pengertian HIV AIDS yang dikutip dari situs aidsindonesia.or.id. Baca artikel terkait lainnya tentang:

• Penyebab HIV AIDS
• Gejala HIV AIDS
• Cara Mencegah Penularan HIV AIDS

DEFINISI
AIDS adalah singkatan dari Acquired Immune Deficiency Syndrome, yaitu sekumpulan gejala yang didapatkan dari penurunan kekebalan tubuh akibat kerusakan system imun yang disebabkan oleh infeksi HIV.
HIV adalah singkatan dari Human Immunodeficiency Virus, yaitu virus yang menyerang sel CD4 dan menjadikannya tempat berkembang biak, kemudian merusaknya sehingga tidak dapat digunakan lagi. Sebagaimana kita ketahui bahwa sel darah putih sangat diperlukan untuk sistem kekebalan tubuh. Tanpa kekebalan tubuh maka ketika tubuh kita diserang penyakit, tubuh kita lemah dan tidak berupaya melawan jangkitan penyakit dan akibatnya kita dapat meninggal dunia meski terkena influenza atau pilek biasa. Manusia yang terkena virus HIV, tidak langsung menderita penyakit AIDS, melainkan diperlukan waktu yang cukup lama bahkan bertahun-tahun bagi virus HIV untuk menyebabkan AIDS atau HIV positif yang mematikan.

PREVALENSI
Penyakit ini sudah lama ada hanya saja belum disadari oleh para ilmuwan bahwa kasus–kasus yang ditemukan adalah kasus AIDS. Baru pada tahun 1981 Amerika Serikat melaporkan kasus–kasus penyakit infeksi yang jarang terjadi ditemukan dikalangan homoseksual, yang kemudian dirumuskan sebagai penyakit Gay Related Immune Deficiency (GRID), yakni penurunan kekebalan tubuh yang dihubungkan dengan kaum gay/homoseksual.
Kemudian pada tahun 1982, CD–USA (Centers for Disease Control) Amerika Serikat untuk pertama kali membuat definisi AIDS. Sejak saat itulah survailans AIDS dimulai. Dan juga ditemukan penyebab kelainan ini adalah LAV (Lymphadenophaty Associaterd Virus ) oleh Luc Montagnier dari pasteur Institut, Paris.
Pada tahun 1984 Gallo dan kawan–kawan dari National Institute of Health, Bethesda, Amerika Serikat menemukan HTLV III ( Human T Lymphotropic Virus type III) sebagai sebab kelainan ini.
Pada tahun 1985 ditemukan Antigen untuk melakukan tes ELISA, suatu tes untuk mengetahui terinfeksi virus itu atau tidaknya seseorang.
Pada tahun 1986, International Commintte on Taxonomi of Viruses, memutuskan nama penyebab penyakit AIDS adalah HIV sebagai pengganti nama LAV dan HTLV III.
15 April 1987, Kasus AIDS di Indonesia pertama kali ditemukan. Seorang wisatawan berusia 44 tahun asal Belanda, Edward Hop, meninggal di Rumah Sakit Sanglah, Bali. Kematian lelaki asing itu disebabkan AIDS. Hingga akhir 1987, ada enam orang yang didiagnosis HIV positif, dua di antara mereka mengidap AIDS.
Sejak ditemukan tahun 1978, secara kumulatif jumlah kasus AIDS di Indonesia sampai dengan 30 September 2009 sebanyak 18.442 kasus. jumlah ini semakin meningkat dari tahun ke tahun.
Data Kementerian Kesehatan akhir 2009 menyebutkan penderita AIDS kelompok umur 20-29 tahun di Indonesia mencapai 49,07 persen. Berikutnya kelompok umur 30-39 tahun dengan 30,14 persen. Berdasarkan jenis kelamin 14720 kasus atau 73,7 persen diderita pria dan 5163 kasus adalah perempuan. Berdasarkan cara penularan, kasus AIDS kumulatif tertinggi melalui hubungan heteroseksual (50,3 persen), pengguna napza suntik/ penasun (40,2 persen), dan hubungan homoseksual (3,3 persen).Jumlah kasus AIDS kumulatif 19.973 kasus yang tersebar di 32 Provinsi di Indonesia. Penderita HIV positif terbanyak berada di DKI Jakarta dari Propinsi DKI Jakarta (7766), disusul Jawa Timur (4553), Jawa Barat (3077), Sumatera Utara (2783), dan Kalimantan Barat (1914).
Pada tahun 2014 diproyeksikan jumlah infeksi baru HIV usia 15-49 tahun sebesar 79.200 dan proyeksi untuk ODHA usia 15-49 tahun sebesar 501.400 kasus. Demikian laporan triwulan ketiga tahun 2009 Surveilans AIDS Ditjen Pengendalian Penyakit dan Penyehatan Lingkungan (PP &PL) Depkes.
CARA PENULARAN
Penularan AIDS dapat dibagi dalam 2 jenis, yaitu :
a. Secara Kontak Seksual
1. Ano-Genital
Cara hubungan seksual ini merupakan perilaku seksual dengan resiko tertinggi bagi penularan HIV, khususnya bagi kaum mitra seksual yang pasif menerima ejakulasi semen dari pengidap HIV.
2. Ora-Genital
Cara hubungan ini merupakan tingkat resiko kedua, termasuk menelan semen dari mitra seksual pengidap HIV.
3. Genito-Genital / Heteroseksual
Penularan secara heteroseksual ini merupakan tingkat penularan ketiga, hubungan suami istri yang mengidap HIV, resiko penularannya, berbeda-beda antara satu peneliti dengan peneliti lainnya.
b. Secara Non seksual
Penularan secara non seksual ini dapat terjadi melalui :
1. Transmisi Parental
Penggunaan jarum dan alat tusuk lain (alat tindik, tatto) yang telah terkontaminasi, terutama pada penyalahgunaan narkotik dengan mempergunakan jarum suntik yang telah tercemar secara bersama-sama. Penularan parental lainnya, melalui transfusi darah atau pemakai produk dari donor dengan HIV positif, mengandung resiko yang sangat tinggi.
2. Transmisi Transplasental
Transmisi ini adalah penularan dari ibu yang mengandung HIV positif ke anak, mempunyai resiko sebesar 50%. Disamping cara penularan yang telah disebutkan di atas ada transmisi yang belum terbukti, antara lain:
1. ASI
2. Saliva/Air liur
3. Air mata
4. Hubungan sosial dengan orang serumah
5. Gigitan serangga
Walaupun cara-cara transmisi di atas belum terbukti, akan tetapi karena prevalensi HIV telah demikian tinginya di Amerika Serikat, maka tetap dianjurkan :
1. Ibu yang mengidap supaya tidak menyusui bayinya.
2. Mengurangi kontaminasi saliva pada alat seduditasi pada saat berciuman dan pada anak-anak yang mengidap HIV yang menderita gangguan jiwa dan sering digigit serangga.
3. bagi dokter ahli mata dianjurkan untuk lebih berhati-hati berhubungan dengan air mata pengidap HIV.
Perlu diketahui AIDS tidak menular karena :
1. Hidup serumah dengan penderita AIDS ( asal tidak mengadakan hubungan seksual )
2. Bersentuhan dengan penderita.
3. Berjabat tangan.
4. Penderita AIDS bersin atau balik di dekat kita.
5. Bersentuhan dengan pakaian atau barang lain dari bekas penderita.
6. Berciuman pipi dengan penderita.
7. Melalui alat makan dan minum.
8. Gigitan nyamuk dan serangga lainnya.
9. Bersama-sama berenang di kolam.
TAHAPAN INFEKSI HIV
Masa Inkubasi penyakit ini belum diketahui secara pasti. Dalam beberapa literatur di katakan bahwa melalui transfusi darah masa inkubasi kira-kira 4,5 tahun, sedangkan pada penderita homoseksual 2 -5 tahun, pada anak- anak rata – rata 21 bulan dan pada orang dewasa 60 bulan.
Ada beberapa Tahapan ketika mulai terinfeksi virus HIV sampai timbul gejala AIDS:
Tahap 1: Periode Jendela
- HIV masuk ke dalam tubuh, sampai terbentuknya antibody terhadap HIV dalam darah
- Tidak ada tanda2 khusus, penderita HIV tampak sehat dan merasa sehat
- Test HIV belum bisa mendeteksi keberadaan virus ini
- Tahap ini disebut periode jendela, umumnya berkisar 2 minggu – 6 bulan
Tahap 2: HIV Positif (tanpa gejala) rata-rata selama 5-10 tahun:
- HIV berkembang biak dalam tubuh
- Tidak ada tanda-tanda khusus, penderita HIV tampak sehat dan merasa sehat
- Test HIV sudah dapat mendeteksi status HIV seseorang, karena telah terbentuk antibody terhadap HIV
-Umumnya tetap tampak sehat selama 5-10 tahun, tergantung daya tahan tubuhnya (rata-rata 8 tahun (di negara berkembang lebih pendek)
Tahap 3: HIV Positif (muncul gejala)
- Sistem kekebalan tubuh semakin turun
- Mulai muncul gejala infeksi oportunistik, misalnya: pembengkakan kelenjar limfa di seluruh tubuh, diare terus menerus, flu, dll
- Umumnya berlangsung selama lebih dari 1 bulan, tergantung daya tahan tubuhnya
Tahap 4: AIDS
- Kondisi sistem kekebalan tubuh sangat lemah
- berbagai penyakit lain (infeksi oportunistik) semakin parah
GEJALA
Terdapat 5 stadium penyakit AIDS, yaitu
1. Gejala awal stadium infeksi yaitu :
Demam
Kelemahan
Nyeri sendi menyerupai influenza/
Nyeri tenggorok
Pembesaran kelenjaran getah bening
2. Stadium tanpa gejala
Stadium dimana penderita nampak sehat, namun dapat merupakan sumber penularan infeksi HIV.
3. Gejala stadium ARC
Demam lebih dari 38°C secara berkala atau terus ��
Menurunnya berat badan lebih dari 10% dalam waktu 3 bulan ��
Pembesaran kelenjar getah bening ��
Diare mencret yang berkala atau terus menerus dalam waktu yang lama tanpa sebab yang jelas ��
Kelemahan tubuh yang menurunkan aktifitas fisik ��
Keringat malam ��
4. Gejala AIDS
Gejala klinis utama yaitu terdapatnya kanker kulit yang disebut �� Sarkoma Kaposi (kanker pembuluh darah kapiler) juga adanya kanker kelenjar getah bening.
Terdapat infeksi penyakit penyerta misalnya pneomonia, �� pneumocystis,TBC, serta penyakit infeksi lainnya seperti teksoplasmosis dsb.
5. Gejala gangguan susunan saraf
Lupa ingatan ��
Kesadaran menurun ��
Perubahan Kepribadian ��
Gejala–gejala peradangan otak atau selaput otak ��
Kelumpuhan ��
Umumnya penderita AIDS sangat kurus, sangat lemah dan menderita infeksi. Penderita AIDS selalu meninggal pada waktu singkat (rata-rata 1-2 tahun) akan tetapi beberapa penderita dapat hidup sampai 3 atau 4 tahun.

PENCEGAHAN
Upaya pencegahan yang dapat di lakukan adalah :
1. Pencegahan penularan melalui jalur non seksual :
a. Transfusi darah cara ini dapat dicegah dengan mengadakan pemeriksaan donor darah sehingga darah yang bebas HIV saja yang ditransfusikan.
b. Penularan AIDS melalui jarum suntik oleh dokter paramedis dapat dicegah dengan upaya sterilisasi yang baku atau menggunakan jarum suntik sekali pakai.
2. Pencegahan penularan melalui jalur seksual
Pencegahan ini dapat dilakukan dengan pendidikan/penyuluhan yang intensif yang ditujukan pada perubahan cara hidup dan perilaku seksual, serta bahayanya AIDS pada usia remaja sampai usia tua. Dan yang utama adalah dengan memperdalam agama Islam yang benar, sehingga menjadi manusia yang bertaqwa menjalankan perintah Allah serta menjauhi larangan Allah dengan ikhlas dan benar. Jika ini terwujud, maka manusia kan selamat dunia akhirat, tidak hanya terhindar dari penyakit AIDS ini akan tetapi mendapatkan kebaikan yang lebih besar daripada itu …

Grafik Jumlah Kasus HIV-AIDS Berdasarkan Provinsi

Berdasarkan kelompok umur, distribusi penderita HIV-AIDS di Indonesia dapat ditampilkan pada tabel berikut :

Grafik Persentase Jumlah Kasus HIV-AIDS Berdasarkan Kelompok Umur

sejarah dan asal usul HIV AIDS

·  ·  ·  Label: ASAL-USUL, KESEHATAN, SEJARAH

KASUS HIV/AIDS ’PERTAMA’
Kejadian ini berawal pada musim panas di Amerika Serikat tahun 1981, ketika itu untuk pertama kalinya oleh Centers for Disease Control and Prevention dilaporkan bahwa ditemukannya suatu peristiwa yang tidak dapat dijelaskan sebelumnya dimana ditemukan penyakit Pneumocystis Carinii Pneumonia (infeksi paru-paru yang mematikan) yang mengenai 5 orang homosexual di Los Angeles, kemudian berlanjut ditemukannnya ’penyakit’ Sarkoma Kaposi yang menyerang sejumlah 26 orang homosexsual di New York dan Los Angeles. Beberapa bulan kemudian penyakit tersebut ditemukan pada pengguna narkoba suntik, segera hal itu juga menimpa para penerima transfusi darah.

Sesuai perkembangan pola epidemiologi penyakit ini, semakin jelaslah bahwa penyebab proses penularan yang paling sering adalah melalui kontak sexual, darah dan produk darah serta cairan tubuh lainnya.

Pada tahun 1983, ditemukan virus HIV pada penderita dan selanjutnya pada tahun 1984 HIV dinyatakan sebagai faktor penyebab terjadinya Aquired Immunodeficiency Syndrom (AIDS).

ASAL-USUL VIRUS HIV
Penemuan kasus AIDS untuk pertama kalinya di Amerika Serikat pada tahun 1981, ternyata hanya sedikit memberi informasi tentang sumber penyakit ini. Sekarang sudah terbukti bahwa AIDS disebabkan oleh virus yang dikenal dengan HIV. Jadi untuk menemukan sumber AIDS kita perlu mencari asal-usul HIV.

HIV adalah bagian dari keluarga atau kelompok lentivirus. Lentivirus seperti HIV dapat ditemukan dalam lingkup luas primata non-manusia. Lentivirus yang lain, diketahui secara kolektif sebagai virus monyet yang dikenal dengan SIV (Simian Immunodeficiency Virus). Dan sekarang secara umum diterima bahwa HIV merupakan keturunan SIV.

Bagaimana HIV dapat menyeberang dari hewan ke manusia?
Telah lama diketahui secara pasti bahwa virus tertentu dapat menyeberang dari hewan kepada manusia dan proses ini dikenal dengan zoonosis. Bagaimana proses SIV menjadi HIV pada manusia?

(1) Teori Pemburu, merupakan teori yang paling banyak dianut. Di dalam teori ini dijelaskan bahwa, SIVcpz dapat berpindah ke manusia, ketika seseorang berburu simpanse kemudian membunuh serta memakan dagingnya. Terkadang virus yang masuk bisa tetap sebagai SIV, atau dalam suatu kesempatan akan berubah menjadi HIV.

(2) Teori Vaksin Polio, merupakan teori lain yang mengatakan bahwa HIV dapat berpindah secara tidak sengaja karena kealpaan pihak medis, misalnya melalui percobaan medis. Teori ini disebarluaskan secara baik dimana vaksin polio yang memainkan peranan dalam perpindahan ini, karena vaksin tersebut dibuat dengan menggunakan ginjal monyet.

(3) Teori Kontaminasi Jarum Suntik, merupakan lanjutan dari “Teori Pemburu”, dimana pada tahun 1950 sudah digalakkan untuk memakai jarum suntik yang hanya sekali pakai serta menerapkan penataan untuk mensterilkan peralatan medis, tetapi ini memakan banyak anggaran sehingga terkadang, satu jarum digunakan untuk beberapa orang tanpa disterilkan terlebih dahulu. Hal tersebut akan mempercepat terkontaminasinya dengan berbagai macam infeksi.

(4) Teori Penjajahan, dasar pemikiran teori ini mengacu pada teori pemburu. Pada akhir abad XIX hingga awal abad XX, sebagian besar negara Afrika mengalami penjajahan. Seperti layaknya warga yang terjajah, rakyat Afrika diwajibkan mengikuti kerja paksa, mereka ditempatkan dalam satu camp dimana sanitasinya sangat buruk, kerja fisik diluar batas serta kebutuhan makanan tidak terjamin bahkan tidak menutup kemungkinan mereka mendapatkan lauk berupa simpanse yang sedang mengidap SIV.

(5) Teori Konspirasi. Beberapa orang mengatakan bahwa virus HIV adalah rekayasa manusia. Dari survey yang dilakukan di Amerika Serikat, didapatkan hasil bahwa sebagian besar responden berkulit hitam mempercayai bahwa virus HIV memang diciptakan untuk memusnahkan sebagian besar orang berkulit hitam serta para homoseksual. Beberapa bahkan meyakini bahwa virus HIV disebarkan di seluruh dunia melalui program imunisasi campak maupun melalui uji coba program vaksinasi Hepatitis B kepada kaum homosexsual.

Sejauh ini, masih belum ada satu teoripun yang mampu menjelaskan dengan memuaskan bagaimana SIV pada binatang bisa menyeberang menjadi HIV pada manusia.

Kapan perpindahan itu terjadi?
Perkembangan dunia kedokteran sejauh ini membuat kita mampu untuk mendeteksi HIV pada darah atau cairan tubuh lainnya, bahkan kita juga sudah mampu menentukan subtype virus HIV. Penelitian terhadap subtype virus HIV pada kasus-kasus awal dapat memberi petunjuk dalam menentukan kapan HIV pertama kali menyerang manusia dan perkembangan berikutnya.

Ada tiga kejadian yang dianggap sebagai infeksi HIV paling awal, yaitu:

1. Contoh plasma (cairan darah) yang diambil dari seorang pria dewasa yang hidup di Republik Demokratik Kongo tahun1959.

2. HIV ditemukan pada contoh jaringan tubuh dari seorang pemuda Amerika–Afrika yang meninggal dunia di St.Louis, AS, tahun 1969.

3. HIV ditemukan pada contoh jaringan tubuh dari seorang pelaut Norwegia yang meninggal dunia sekitar tahun1976.

Analisis yang dilakukan pada tahun 1998 tentang contoh plasma dari 1959 mengesankan bahwa HIV-1 memasuki manusia sekitar 1940-an atau awal 1950-an, lebih awal dari yang diperkirakan sebelumnya.


Dimana virus HIV pertama kali muncul pada manusia?
Karena HIV berkembang dari satu jenis SIV yang ditemukan pada tipe simpanse di Afrika Barat, banyak orang menganggap bahwa HIV pertama muncul pada manusia di sana. Kemudian dianggap bahwa HIV menyebar dari Afrika ke seluruh dunia.

Kita mungkin tidak akan pernah tahu secara pasti

kapan dan dimana virus HIV muncul pertama kali, tetapi yang jelas pada suatu waktu di pertengahan abad 20-an ini, infeksi HIV pada manusia berkembang menjadi epidemi penyakit di seluruh dunia yang saat ini lebih dikenal sebagai AIDS.



Apa penyebab epidemi ini menyebar secara tiba-tiba?
Dipercayai ada 3 proses yang mempermudah penularan sehingga menyebabkan penyebaran secara luas :

Kemudahan transportasi, memegang peranan dalam penyebaran HIV disorot pada kasus yang sekarang dikenal sebagai ’Patient Zero’. Patient Zero adalah seorang pramugara pesawat terbang berkebangsaan Kanada dan bernama Gaetan Dugas yang sering mengadakan perjalanan ke seluruh dunia. Analisis terhadap beberapa kasus AIDS awal menunjukkan bahwa orang terinfeksi tersebut adalah orang yang berhubungan seksual baik langsung maupun tidak langsung dengan pramugara ini. Untuk lebih jelasnya bisa menonton film ”and the band played on”.

Industri darah. Ketika transfusi darah menjadi bagian yang rutin dalam praktek kedokteran, permintaan kebutuhan akan darah juga semakin meningkat. Di beberapa negara seperti Amerika, mereka yang bersedia menyumbangkan darahnya akan dibayar, termasuk pengguna narkoba suntik. Pada awal epidemi, para dokter belum menyadari akan mudahnya virus ini menyebar melalui donor darah tanpa screening sebelumnya. Akibatnya, banyak dari mereka yang mendapat transfusi dari seseorang yang terinfeksi HIV akan tertular HIV.

Penggunaan Narkoba. Meningkatnya ketersediaan heroin seiring dengan perang Vietnam tahun 1970-an, mendorong pertumbuhan penggunaan narkoba suntik. Bersamaan dengan hal tersebut, untuk menghemat biaya, pemakaian alat suntik oleh para pecandu dilakukan secara bersama-sama, satu jarum dipakai oleh banyak pecandu tanpa disterilkan terlebih dahulu. Ini merupakan jalan lain virus HIV berpindah dari pengidap yang satu ke pengidap lainnya.


KENYATAAN DI NEGARA KITA
Rupaya era globalisasi saat ini menyebabkan dunia tampak semakin kecil, negara tidak mempunyai batas-batas lagi. Perpindahan penduduk menjadi begitu mudah, demikian juga dengan HIV, bisa berpindah dari satu negara ke negara lainnya dengan leluasa hingga akhirnya sampai ke Indonesia. Kasus HIV/AIDS pertama di Indonesia diidentifikasi di Bali pada seorang laki-laki asing yang kemudian meninggal pada April 1987. Akan tetapi, penyebaran HIV di Indonesia meningkat setelah tahun 1995. Hal ini dapat dilihat pada tes penapisan (screening) darah donor yang positif HIV meningkat dari 3 per 100.000 kantong pada 1994 menjadi 16 per 100.000 kantong pada tahun 2000. Peningkatan 5 kali lebih tinggi dalam waktu 6 tahun.

Pada tahun 2000 terjadi peningkatan penyebaran epidemi HIV secara nyata melalui pekerja seks. Data dari Tanjung Balai Karimui Merauke, Propinsi Irian Jaya prevalensi HIV pada pekerja seks amat tinggi yaitu 26,5% sedangkan di Propinsi Jawa Barat 5,5% dan di DKI Jakarta 3,36%.

Sejak tahun 1999 terjadi fenomena baru penyebaran HIV/AIDS yaitu infeksi HIV mulai terlihat pada para pengguna Narkoba suntik. Penularan pada kelompok ini terjadi secara cepat karena penggunaan jarum suntik bersama. Sebagai contoh, pada tahun 1999 hanya 18% pengguna narkoba suntik yang dirawat di Rumah Sakit Ketergantungan Obat (RSKO) Jakarta yang terinfeksi HIV. Akan tetapi pada tahun 2000 angka tersebut meningkat dengan cepat menjadi 40% dan pada tahun 2001 menjadi 48%.

Fakta baru pada 2002 menunjukkan bahwa penularan infeksi HIV juga telah meluas ke rumah tangga. Di beberapa wilayah di Jakarta dilaporkan bahwa sekitar 3% dari 500 ibu hamil yang dites secara sukarela dalam kegiatan VCT (Voluntary Counseling and Testing) sudah terinfeksi HIV.

Jadi, semua jenis penularan HIV ada di negara kita dan sudah mengenai siapa saja bahkan hingga ke ibu rumah tangga dan bayi yang dikandungnya.

Chord Gitar dan Lirik Lagu Drive Bersama Bintang :

Intro : C Am Em 2x

C        Am          Em
 Senja kini berganti malam
C        Am          Em
 Menutup hari yang lelah
F      C            Dm
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F        C         G
 Aku tak tahu di mana

C         Am       Em
 Pernah kita lalui semua
C          Am            Em
 Jerit, tangis, canda, tawa
F       C           Dm
 Kini hanya untaian kata
F       C           E
 Hanya itulah yang aku punya

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Am Em     F       C
 Tidurlah, selamat malam
Dm C        E
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Am  Em   F       C
 Mimpilah dalam tidurmu
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 Bersama bintang

C Am Em 2x

C         Am          Em
 Sesungguhnya aku tak bisa
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 Jalani waktu tanpamu
F       C            Dm
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Back to Reff :

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Human factors and ergonomics

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Human factors and Ergonomics (HF&E) is a multidisciplinary field incorporating contributions from psychology, engineering, industrial design, graphic design, statistics, operations research and anthropometry. In essence it is the study of designing equipment and devices that fit the human body and its cognitive abilities. The two terms "human factors" and "ergonomics" are essentially synonymous.^[1][2]
The International Ergonomics Association defines ergonomics or human factors as follows:^[2]

Ergonomics (or human factors) is the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance.

HF&E is employed to fulfill the goals of health and safety and productivity. It is relevant in the design of such things as safe furniture and easy-to-use interfaces to machines and equipment. Proper ergonomic design is necessary to prevent repetitive strain injuries and other musculoskeletal disorders, which can develop over time and can lead to long-term disability.
Human factors and ergonomics is concerned with the ‘fit’ between the user, equipment and their environments. It takes account of the user's capabilities and limitations in seeking to ensure that tasks, functions, information and the environment suit each user.
To assess the fit between a person and the used technology, human factors specialists or ergonomists consider the job (activity) being done and the demands on the user; the equipment used (its size, shape, and how appropriate it is for the task), and the information used (how it is presented, accessed, and changed). Ergonomics draws on many disciplines in its study of humans and their environments, including anthropometry, biomechanics, mechanical engineering, industrial engineering, industrial design, information design, kinesiology, physiology and psychology.

Contents  [hide]  1 Etymology 2 History of the field 3 HF&E Organisations 3.1 Related organizations 4 Specialisations 5 Applications 6 Practitioners 7 Methods 7.1 Weaknesses of HF&E Methods 8 See also 9 References 10 Further reading 11 External links

[edit] Etymology

Ergonomics: the science of designing user interaction with equipment and workplaces to fit the user.

The term ergonomics, from Greek Έργον, meaning "work", and Νόμος, meaning "natural laws", first entered the modern lexicon when Wojciech Jastrzębowski used the word in his 1857 article Rys ergonomji czyli nauki o pracy, opartej na prawdach poczerpniętych z Nauki Przyrody (The Outline of Ergonomics, i.e. Science of Work, Based on the Truths Taken from the Natural Science).^[3] The introduction of the term to the English lexicon is widely attributed to British psychologist Hywel Murrell, at the 1949 meeting at the UK's Admiralty, which led to the foundation of The Ergonomics Society. He used it to encompass the studies in which he had been engaged during and after the World War II.^[4]
The expression human factors is a North American term which has been adopted to emphasise the application of the same methods to non work-related situations. A "human factor" is a physical or cognitive property of an individual or social behavior specific to humans that may influence the functioning of technological systems. The terms "human factors" and "ergonomics" are essentially synonymous.^[1]

[edit] History of the field

The foundations of the science of ergonomics appear to have been laid within the context of the culture of Ancient Greece. A good deal of evidence indicates that Greek civilization in the 5th century BC used ergonomic principles in the design of their tools, jobs, and workplaces. One outstanding example of this can be found in the description Hippocrates gave of how a surgeon's workplace should be designed and how the tools he uses should be arranged.^[5] The archaeological record also shows that the early Egyptian dynasties made tools and household equipment that illustrated ergonomic principles. It is therefore questionable whether the claim by Marmaras, et al., regarding the origin of ergonomics, can be justified.^[6]
In the 19th century, Frederick Winslow Taylor pioneered the "scientific management" method, which proposed a way to find the optimum method of carrying out a given task. Taylor found that he could, for example, triple the amount of coal that workers were shoveling by incrementally reducing the size and weight of coal shovels until the fastest shoveling rate was reached.^[7] Frank and Lillian Gilbreth expanded Taylor's methods in the early 1900s to develop the "time and motion study". They aimed to improve efficiency by eliminating unnecessary steps and actions. By applying this approach, the Gilbreths reduced the number of motions in bricklaying from 18 to 4.5, allowing bricklayers to increase their productivity from 120 to 350 bricks per hour.^[7]
Previous to World War I the focus of aviation psychology was on the aviator himself, but the war shifted the focus onto the aircraft, in particular, the design of controls and displays, the effects of altitude and environmental factors on the pilot. The war saw the emergence of aeromedical research and the need for testing and measurement methods. Studies on driver behaviour started gaining momentum during this period, as Henry Ford started providing millions of Americans with automobiles. Another major development during this period was the performance of aeromedical research. By the end of WWI, two aeronautical labs were established, one at Brooks Airforce Base, Texas and the other at Wright field outside of Dayton, Ohio. Many tests were conducted to determine which characteristic differentiated the successful pilots from the unsuccessful ones. During the early 1930s, Edwin Link developed the first flight simulator. The trend continued and more sophisticated simulators and test equipment were developed. Another significant development was in the civilian sector, where the effects of illumination on worker productivity were examined. This led to the identification of the Hawthorne Effect, which suggested that motivational factors could significantly influence human performance.^[7]
World War II marked the development of new and complex machines and weaponry, and these made new demands on operators' cognition. it was no longer possible to adopt the Tayloristic principle of matching individuals to preexisting jobs. Now the design of equipment had to take into account human limitations and take advantage of human capabilities. The decision-making, attention, situational awareness and hand-eye coordination of the machine's operator became key in the success or failure of a task. There was a lot of research conducted to determine the human capabilities and limitations that had to be accomplished. A lot of this research took off where the aeromedical research between the wars had left off. An example of this is the study done by Fitts and Jones (1947), who studied the most effective configuration of control knobs to be used in aircraft cockpits. A lot of this research transcended into other equipment with the aim of making the controls and displays easier for the operators to use. The entry of the terms "human factors" and "ergonomics" into the modern lexicon date from this period. It was observed that fully functional aircraft, flown by the best-trained pilots, still crashed. In 1943, Alphonse Chapanis, a lieutenant in the U.S. Army, showed that this so-called "pilot error" could be greatly reduced when more logical and differentiable controls replaced confusing designs in airplane cockpits. After the war, the Army Air Force published 19 volumes summarizing what had been established from research during the war.^[7]
In the decades since WWII, HF&E has continued to flourish and diversify. Work by Elias Porter and others within the RAND Corporation after WWII extended the conception of HF&E. "As the thinking progressed, a new concept developed - that it was possible to view an organization such as an air-defense, man-machine system as a single organism and that it was possible to study the behavior of such an organism. It was the climate for a breakthrough."^[8] In the initial 20 years after the WWII, most activities were done by the "founding fathers": Alphonse Chapanis, Paul Fitts, and Small.^{[citation needed]}
The beginning of The Cold War led to a major expansion of Defense supported research laboratories. Also, a lot of labs established during WWII started expanding. Most of the research following the war was military-sponsored. Large sums of money were granted to universities to conduct research. The scope of the research also broadened from small equipments to entire workstations and systems. Concurrently, a lot of opportunities started opening up in the civilian industry. The focus shifted from research to participation through advice to engineers in the design of equipment. After 1965, the period saw a maturation of the discipline. The field has expanded with the development of the computer and computer applications.^[7]
The Space Age created new human factors issues such as weightlessness and extreme g-forces. Tolerance of the harsh environment of space and it's effects on the mind and body were widely studied^{[citation needed]}
The dawn of the Information Age has resulted in the related field of Human–computer interaction (HCI). Likewise, the growing demand for and competition among consumer goods and electronics has resulted in more companies including human factors in product design.

[edit] HF&E Organisations

Formed in 1946 in the UK, the oldest professional body for human factors specialists and ergonomists is The Institute of Ergonomics and Human Factors, formally known as The Ergonomics Society.
The Human Factors and Ergonomics Society (HFES) was founded in 1957. The Society's mission is to promote the discovery and exchange of knowledge concerning the characteristics of human beings that are applicable to the design of systems and devices of all kinds.
The International Ergonomics Association (IEA) is a federation of ergonomics and human factors societies from around the world. The mission of the IEA is to elaborate and advance ergonomics science and practice, and to improve the quality of life by expanding its scope of application and contribution to society. As of September 2008, the International Ergonomics Association has 46 federated societies and 2 affiliated societies.

[edit] Related organizations

The Institute of Occupational Medicine (IOM) was founded by the coal industry in 1969, from the outset the IOM employed ergonomics staff to apply ergonomics principles to the design of mining machinery and environments. To this day, the IOM continues ergonomics activities, especially in the fields of musculoskeletal disorders; heat stress and the ergonomics of personal protective equipment (PPE). Like many in occupational ergonomics, the demands and requirements of an ageing UK workforce are a growing concern and interest to IOM ergonomists.
The International Society of Automotive Engineers (SAE) is a professional organization for mobility engineering professionals in the aerospace, automotive, and commercial vehicle industries. The Society is a standards development organization for the engineering of powered vehicles of all kinds, including cars, trucks, boats, aircraft, and others. The Society of Automotive Engineers has established a number of standards used in the automotive industry and elsewhere. It encourages the design of vehicles in accordance with established Human Factors principles. It is one the most influential organizations with respect to Ergonomics work in Automotive design. This society regularly holds conferences which address topics spanning all aspects of Human Factors/Ergonomics.^{[citation needed]}

[edit] Specialisations

Specialisations within this field include visual ergonomics, cognitive ergonomics, usability, human–computer interaction, and user experience engineering. New terms are being generated all the time. For instance, “user trial engineer” may refer to a human factors professional who specialises in user trials.^{[citation needed]} Although the names change, human factors professionals apply an understanding of human factors to the design of equipment, systems and working methods in order to improve comfort, health, safety and productivity.
According to the International Ergonomics Association within the discipline of ergonomics there exist domains of specialization:

• Physical ergonomics is concerned with human anatomy, and some of the anthropometric, physiological and bio mechanical characteristics as they relate to physical activity.^[2]
• Cognitive ergonomics is concerned with mental processes, such as perception, memory, reasoning, and motor response, as they affect interactions among humans and other elements of a system. (Relevant topics include mental workload, decision-making, skilled performance, human-computer interaction, human reliability, work stress and training as these may relate to human-system and Human-Computer Interaction design.)^[2]
• Organizational ergonomics is concerned with the optimization of socio-technical systems, including their organizational structures, policies, and processes.(Relevant topics include communication, crew resource management, work design, design of working times, teamwork, participatory design, community ergonomics, cooperative work, new work programs, virtual organizations, telework, and quality management.)^[2]
• Environmental ergonomics is concerned with human interaction with the environment. The physical environment is characterized by: climate, temperature, pressure, vibration, light.^[9]

There are more than twenty technical subgroups within the Human Factors and Ergonomics Society^[10] (HFES), which indicates the range of applications for ergonomics.

[edit] Applications

Human factors issues arise in simple systems and consumer products as well. Some examples include cellular telephones and other hand held devices that continue to shrink yet grow more complex (a phenomenon referred to as "creeping featurism"), millions of VCRs blinking "12:00" across the world because very few people can figure out how to program them, or alarm clocks that allow sleepy users to inadvertently turn off the alarm when they mean to hit 'snooze'. A user-centered design (UCD), also known as a systems approach or the usability engineering life cycle aims to improve the user-system. Ergonomic principles have been widely used in the design of both consumer and industrial products. Past examples include screwdriver handles made with serrations to improve finger grip, and use of soft thermoplastic elastomers to increase friction between the skin of the hand and the handle surface.^{[citation needed]}
HF&E continues to be successfully applied in the fields of aerospace, aging, health care, IT, product design, transportation, training, nuclear and virtual environments, among others. Physical ergonomics is important in the medical field, particularly to those diagnosed with physiological ailments or disorders such as arthritis (both chronic and temporary) or carpal tunnel syndrome. Pressure that is insignificant or imperceptible to those unaffected by these disorders may be very painful, or render a device unusable, for those who are. Many ergonomically designed products are also used or recommended to treat or prevent such disorders, and to treat pressure-related chronic pain.^{[citation needed]}
One of the most prevalent types of work-related injuries are musculoskeletal disorders. Work-related musculoskeletal disorders (WRMDs) result in persistent pain, loss of functional capacity and work disability, but their initial diagnosis is difficult because they are mainly based on complaints of pain and other symptoms.^[11] Every year 1.8 million U.S. workers experience WRMDs and nearly 600,000 of the injuries are serious enough to cause workers to miss work.^[12] Certain jobs or work conditions cause a higher rate worker complaints of undue strain, localized fatigue, discomfort, or pain that does not go away after overnight rest. These types of jobs are often those involving activities such as repetitive and forceful exertions; frequent, heavy, or overhead lifts; awkward work positions; or use of vibrating equipment.^[13] The Occupational Safety and Health Administration (OSHA) has found substantial evidence that ergonomics programs can cut workers' compensation costs, increase productivity and decrease employee turnover.^[14] Therefore, it is important to gather data to identify jobs or work conditions that are most problematic, using sources such as injury and illness logs, medical records, and job analyses.^[13]
The emerging field of human factors in highway safety uses human factor principles to understand the actions and capabilities of road users - car and truck drivers, pedestrians, bicyclists, etc. - and use this knowledge to design roads and streets to reduce traffic collisions. Driver error is listed as a contributing factor in 44% of fatal collisions in the United States, so a topic of particular interest is how road users gather and process information about the road and its environment, and how to assist them to make the appropriate decision. ^[15]

[edit] Practitioners

Human factors practitioners come from a variety of backgrounds, though predominantly they are psychologists (from the various subfields of engineering psychology, cognitive psychology, perceptual psychology, applied psychology and experimental psychology) and physiologists. Designers (industrial, interaction, and graphic), anthropologists, technical communication scholars and computer scientists also contribute. Typically, an ergonomist will have an undergraduate degree in psychology, engineering, design or health sciences, and usually a masters degree or doctoral degree in a related discipline. Though some practitioners enter the field of human factors from other disciplines, both M.S. and Ph.D. degrees in Human Factors Engineering are available from several universities worldwide. The Human Factors Research Group (HFRG) at the University of Nottingham provides human factors courses at both at MSc and PhD level including a distance learning course in Applied Ergonomics.^[16] Other Universities to offer postgraduate courses in human factors in the UK include Loughborough University, Cranfield University and the University of Oxford.^{[citation needed]}

[edit] Methods

Until recently, methods used to evaluate human factors and ergonomics ranged from simple questionnaires to more complex and expensive usability labs.^[17] Some of the more common HF&E methods are listed below:

• Ethnographic analysis: Using methods derived from ethnography, this process focuses on observing the uses of technology in a practical environment. It is a qualitative and observational method that focuses on "real-world" experience and pressures, and the usage of technology or environments in the workplace. The process is best used early in the design process.^[18]

• Focus Groups are another form of qualitative research in which one individual will facilitate discussion and elicit opinions about the technology or process under investigation. This can be on a one to one interview basis, or in a group session. Can be used to gain a large quantity of deep qualitative data,^[19] though due to the small sample size, can be subject to a higher degree of individual bias.^[20] Can be used at any point in the design process, as it is largely dependent on the exact questions to be pursued, and the structure of the group. Can be extremely costly.

• Iterative design: Also known as prototyping, the iterative design process seeks to involve users at several stages of design, in order to correct problems as they emerge. As prototypes emerge from the design process, these are subjected to other forms of analysis as outlined in this article, and the results are then taken and incorporated into the new design. Trends amongst users are analyzed, and products redesigned. This can become a costly process, and needs to be done as soon as possible in the design process before designs become too concrete.^[18]

• Meta-analysis: A supplementary technique used to examine a wide body of already existing data or literature in order to derive trends or form hypotheses in order to aid design decisions. As part of a literature survey, a meta-analysis can be performed in order to discern a collective trend from individual variables.^[20]

• Subjects-in-tandem: Two subjects are asked to work concurrently on a series of tasks while vocalizing their analytical observations. This is observed by the researcher, and can be used to discover usability difficulties. This process is usually recorded.^{[citation needed]}

• Surveys and Questionnaires: A commonly used technique outside of Human Factors as well, surveys and questionnaires have an advantage in that they can be administered to a large group of people for relatively low cost, enabling the researcher to gain a large amount of data. The validity of the data obtained is, however, always in question, as the questions must be written and interpreted correctly, and are, by definition, subjective. Those who actually respond are in effect self-selecting as well, widening the gap between the sample and the population further.^[20]

• Task analysis: A process with roots in activity theory, task analysis is a way of systematically describing human interaction with a system or process to understand how to match the demands of the system or process to human capabilities. The complexity of this process is generally proportional to the complexity of the task being analyzed, and so can vary in cost and time involvement. It is a qualitative and observational process. Best used early in the design process.^[20]

• Think aloud protocol: Also known as "concurrent verbal protocol", this is the process of asking a user to execute a series of tasks or use technology, while continuously verbalizing their thoughts so that a researcher can gain insights as to the users' analytical process. Can be useful for finding design flaws that do not affect task performance, but may have a negative cognitive affect on the user. Also useful for utilizing experts in order to better understand procedural knowledge of the task in question. Less expensive than focus groups, but tends to be more specific and subjective.^[21]

• User analysis: This process is based around designing for the attributes of the intended user or operator, establishing the characteristics that define them, creating a persona for the user. Best done at the outset of the design process, a user analysis will attempt to predict the most common users, and the characteristics that they would be assumed to have in common. This can be problematic if the design concept does not match the actual user, or if the identified are too vague to make clear design decisions from. This process is, however, usually quite inexpensive, and commonly used.^[20]

• "Wizard of Oz": This is a comparatively uncommon technique but has seen some use in mobile devices. Based upon the Wizard of Oz experiment, this technique involves an operator who remotely controls the operation of a device in order to imitate the response of an actual computer program. It has the advantage of producing a highly changeable set of reactions, but can be quite costly and difficult to undertake.

• Methods Analysis is the process of studying the tasks a worker completes using a step-by-step investigation. Each task in broken down into smaller steps until each motion the worker performs is described. Doing so enables you to see exactly where repetitive or straining tasks occur.

• Time studies determine the time required for a worker to complete each task. Time studies are often used to analyze cyclical jobs. They are considered “event based” studies because time measurements are triggered by the occurrence of predetermined events.^[22]

• Work sampling is a method in which the job is sampled at random intervals to determine the proportion of total time spent on a particular task.^[22] It provides insight into how often workers are performing tasks which might cause strain on their bodies.

• Predetermined time systems are methods for analyzing the time spent by workers on a particular task. One of the most widely used predetermined time system is called Methods-Time-Measurement or MTM. Other common work measurement systems include MODAPTS and MOST.^{[citation needed]}

• Cognitive Walkthrough: This method is a usability inspection method in which the evaluators can apply user perspective to task scenarios to identify design problems. As applied to macroergonomics, evaluators are able to analyze the usability of work system designs to identify how well a work system is organized and how well the workflow is integrated.^[23]

• Kansei Method: This is a method that transforms consumer’s responses to new products into design specifications. As applied to macroergonomics, this method can translate employee’s responses to changes to a work system into design specifications.^[23]

• High Integration of Technology, Organization, and People (HITOP): This is a manual procedure done step-by-step to apply technological change to the workplace. It allows managers to be more aware of the human and organizational aspects of their technology plans, allowing them to efficiently integrate technology in these contexts.^[23]

• Top Modeler: This model helps manufacturing companies identify the organizational changes needed when new technologies are being considered for their process.^[23]

• Computer-integrated Manufacturing, Organization, and People System Design (CIMOP): This model allows for evaluating computer-integrated manufacturing, organization, and people system design based on knowledge of the system.^[23]

• Anthropotechnology: This method considers analysis and design modification of systems for the efficient transfer of technology from one culture to another.^[23]

• Systems Analysis Tool (SAT): This is a method to conduct systematic trade-off evaluations of work-system intervention alternatives.^[23]

• Macroergonomic Analysis of Structure (MAS): This method analyzes the structure of work systems according to their compatibility with unique sociotechnical aspects.^[23]

• Macroergonomic Analysis and Design (MEAD): This method assesses work-system processes by using a ten-step process.^[23]

• Virtual Manufacturing and Response Surface Methodology (VMRSM): This method uses computerized tools and statistical analysis for workstation design.^[24]

[edit] Weaknesses of HF&E Methods

Problems in how usability measures are employed include the fact that measures of learning and retention of how to use an interface are rarely employed during methods and some studies treat measures of how users interact with interfaces as synonymous with quality-in-use, despite an unclear relation.^[25]
Although field methods can be extremely useful because they are conducted in the users natural environment, they have some major limitations to consider. The limitations include:

1. Usually take more time and resources than other methods
2. Very high effort in planning, recruiting, and executing than other methods
3. Much longer study periods and therefore requires much goodwill among the participants
4. Studies are longitudinal in nature, therefore, attrition can become a problem