Correlation Between Cutting Force and Residual Stress in Dry End-Milling of Inconel HX

Residual stress in the end-milled subsurface can significantly affect the fatigue performance of end-milled material. In the end-milling process, the generation of residual stress is extremely complex, which is closely related to the spindle speed, feed per tooth and cutting force. Thus, it is crucial to elucidate the influence of spindle speed and feed per tooth on cutting force and residual stress, also the correlation between cutting force and residual stress in terms of spindle speed and feed per tooth. According to this, dry end-milling of Inconel HX was performed by climb-milling using Kennametal KYS40 solid ceramic end-mill. From this experimental test, cutting force and residual stress showed a U-shaped relationship with the increase of spindle speed, while cutting force and residual stress showed a linear relationship with the increase of feed per tooth. Furthermore, for low cutting force and residual stress, the focus should be on choosing the optimum combination of spindle speed (21,400 to 24,100 rpm) and feed per tooth (0.014 to 0.016 mm/tooth)

Correlation Between Cutting Force and Residual Stress in Dry End-Milling of Inconel HX

Residual stress in the end-milled subsurface can significantly affect the fatigue performance of end-milled material. In the end-milling process, the generation of residual stress is extremely complex, which is closely related to the spindle speed, feed per tooth and cutting force. Thus, it is crucial to elucidate the influence of spindle speed and feed per tooth on cutting force and residual stress, also the correlation between cutting force and residual stress in terms of spindle speed and feed per tooth. According to this, dry end-milling of Inconel HX was performed by climb-milling using Kennametal KYS40 solid ceramic end-mill. From this experimental test, cutting force and residual stress showed a U-shaped relationship with the increase of spindle speed, while cutting force and residual stress showed a linear relationship with the increase of feed per tooth. Furthermore, for low cutting force and residual stress, the focus should be on choosing the optimum combination of spindle speed (21,400 to 24,100 rpm) and feed per tooth (0.014 to 0.016 mm/tooth)

The Impact of ICT on Career Counseling Services: A case Study of Nigerian Secondary Schools

Information and communication technologies (ICT) will need to be fully integrated into the delivery of careers services as the world is now in the global era. Such integration would not only have the potential to achieve more but would also increase the flexibility of services and enhance their quality. Career choice is an  important  decision  a  person  needs  to  make  in  his  life  time.  Unfortunately, many young people find it uneasy to make appropriate career choice. The  paper  focused  on  the  usage  of  career  counseling  services  in  selected public secondary schools in Nigeria. It sought to find out how students and teachers utilize  career  counseling  services,  students’  expectations  in  career  counseling services  and  how  school  principals  support  career  counseling  services.  Simple random  sampling  was  used  to  select  380  from 34  public  secondary  schools  from  the  sample  population.  Four-point Likert scale questionnaires were used to obtain data for the study. The findings revealed that the students use career counseling services to take career decision and aspiration, gather career information and select and take subjects that match their career interest. Secondary school teachers use career counseling services to guide students to make appropriate subject choice that match their career interest and help them with their career challenges and plans. This paper recommends that career counselors should integrate use of ICT, through the use of chat rooms, email and social networking. In other words several choice of career could be show to the students on DVD and CD Video. They should also be exposed to TV and radio Chat on Career choice.DOI: http://dx.doi.org/10.11591/ijere.v1i1.70

An Assessment of Risk of Iodine Deficiency Among Pregnant Women in Sarawak, Malaysia

Previous findings from a state-wide Iodine Deficiency Disorders (IDD) study among pregnant women (PW) in Sarawak indicated that PW are at risk of IDD and further assessment is needed. This paper describes the methodology used in conducting this study for an assessment of risk of iodine deficiency among pregnant women in Sarawak, Malaysia. A total of 30 maternal child health care clinics (MCHCs) were selected using probability proportional to population size (PPS) sampling technique. The PW sample size was calculated based on 95% confidence interval (CI), relative precision of 5%, design effect of 2, anticipated IDD prevalence of 65.0% and non-response rate of 20%. Thus, the total sample size required was 750 (25 respondents per selected MCHC). The WHO Expanded Programme on Immunization (EPI) surveys approach was used to randomly select the first respondent and subsequent respondents were chosen until the required number of PW was met. The required data were obtained through: face-to-face interviews (socio-demographic and food frequency questionnaire), clinical assessments (thyroid size, and hyper/hypothyroidism) and biochemical analysis (urine and blood serum). A total of 677 PW responded in the study with a response rate of 90.2%. Majority of the PW were at second gravida, aged 25-29 years old and of Malay ethnicity. The methodology used in this study was based on International guidelines which may provide state's estimates. All the necessary steps were taken into consideration to ensure valid and reliable findings on current iodine status among PW

Effects of feeding metabolite combinations from Lactobacillus plantarum on plasma and breast meat lipids in broiler chickens.

The effects of feeding different doses of metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456) on cholesterol reduction in plasma and breast meat in broiler chickens and the possible mechanism was studied. A total of 504 male Ross broilers were grouped into 7 treatments and offered with different diets: (i) standard corn-soybean based diet (-ve control); (ii) standard cornsoybean based diet + neomycin and oxytetracycline (+ve control); (iii) standard corn-soybean based diet + 0.1% metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456); (iv) standard corn-soybean based diet + 0.2% of Com3456; (v) standard cornsoybean based diet + 0.3% of Com3456 (vi) standard corn-soybean based diet + 0.4% of Com3456 and (vii) standard corn-soybean based diet + 0.5% of Com3456. The metabolite combinations supplemented in the diet of broilers reduced protein, cholesterol esters concentration in very low-density lipoprotein particles. The present of organic acids and proteinaceous compound in the metabolite combinations as found in previous study also increased lactic acid bacteria count in small intestine digesta and improved bile salts deconjugation ability of lactic acid bacteria

Dipeptidyl peptidase IV (DPP IV) inhibitory activity screening of Momordica charantia, Taraxacum officinale and Trigonella foenum-graecumextracts in vitro

Diabetes, a globally popular disease which attracted the attention of many researches worldwide to discover a non-toxic and side effect free remedy for this disease. Inhibition of DPP IV enzymes has been adopted as one of the strategies in recent years in controlling diabetes. DPP IV inhibitor inhibits the dipeptidyl peptidase enzyme which degrades several incretin hormones that are vital in the production of insulin and managing the blood glucose level.Thus, the present study was designed to investigate the DPP IV inhibitory effects of plants having antidiabetic property. In vitro DPP IV inhibition was evaluated by the specific inhibitory activity of Momordica charantia (whole fruit), Taraxacum officinale (whole plant) and Trigonella foenum-graecum (seed) extracts prepared with heat treatment using petroleum ether, acetone, ethanol and water as solvents. Among the tested plants T. officinale and M. charantia acetone extracts exhibited strong DPP IV activity inhibition, with 78.88% and 54.13% respectively. The present study is the first report on screening of DPP IV inhibitory activity of T. officinale, M. charantiaand T. foenum-graecum extracts. This could provide a new insight into DPP IV inhibitors from plants that could be useful for treatment of type 2 diabetes

Integration of SPT (N-value), mackintosh probe (M-value) and resistivity values for soft soil assessment

2-D resistivity method has been used in association with Mackintosh probe and Standard Penetration Test (SPT) to investigate the ground properties at Universiti Sains Malaysia, Pulau Pinang. The purpose of this study was to determine the resistivity value of the subsurface material together with N-value and M-value of the particular location. The study also aimed to evaluate whether there is any correlation could be made by the parameters measured. Borehole record revealed that two types of soil exist up to 13 m; loose sand and stiff sandy silt. The loose sand recorded N-value of 8 and M-value of 170 having resistivity value of 790 Ohm.m. On the other hand, stiff sandy silt recorded N-value of 9-11, M-value of 135-170 and showing resistivity value of 415-785 Ohm.m. The results showed no clear relation between those geotechnical strength parameters with the resistivity imaging result. It is due to non-existence of distinctive differences in the electrical conductivity of the mentioned ground material when they are in the low strength bracket. However, the resistivity result suggested the presence of higher resistance material that is dry loose sand. The resistivity result was able to detect the water saturated zone near the ground surface, which showed low N-value and M-value

Dynamic Mechanical and Gel Content Properties of Irradiated ENR/PVC Blends with TiO2 Nanofillers

Numerous studies reported on irradiated epoxidized natural rubber/polyvinyl chloride (ENR/PVC) blends and the blends were found miscible at all compositional range thus it offers a broad of opportunity in modifying the blend characteristic. Addition of low loading titanium dioxide (TiO2) nanofillers in the ENR/PVC blends has shown a remarkable increment in tensile strength. Thus, this study was initiated to address the effect of TiO2 nanofillers on ENR/PVC blends dynamic mechanical and gel content properties and its morphology upon exposure to electron beam irradiation. ENR/PVC blends with addition of 0, 2 and 6 phr TiO2 nanofillers were first blended in a mixing chamber before being irradiated by an electron beam accelerator at different 0-200 kGy irradiation doses. The influence of TiO2 nanofillers on the irradiation crosslinking of ENR/PVC blends was study based on the dynamic mechanical analysis which was carried out in determining the glass transition temperature and the storage modulus behavior of ENR/PVC blends incorporated with TiO2 nanofillers. Formations of irradiation crosslinking in the blend were investigated by gel content measurement. While, the TiO2 nanofillers distribution were examined by Transmission Electron Microscope (TEM). Upon irradiation, the ENR/PVC/6 phr TiO2 formed the highest value of gel fraction. For dynamic mechanical analysis, it was found that electron beam radiation increased the Tg of all the compositions. The relationship between the crosslinking and the stiffness of the nanocomposites also can be found in this study. The enhancement in the storage modulus and Tg at higher amount of TiO2 in the blend could be correlated to the enhancement of the irradiation-induced crosslinking in the nanocomposites characteristic and also with the higher agglomerations of TiO2 evidence shown from the TEM micrograph examination. Lastly, the dimensions of TiO2 in the blends were found less than 100 nm in diameter which indicates incorporation of TiO2 nanofillers in ENR/PVC blends is potentially to provide the nanocomposites features. Doi: 10.12777/ijse.6.1.24-30 [How to cite this article: Ramlee, N.A., Ratnam, C.T., Alias, N.H., Rahman, M.F.A.. 2014. Dynamic Mechanical and Gel Content Properties of Irradiated ENR/PVC blends with TiO2 Nanofillers. International Journal of Science and Engineering, 6(1),24-30. Doi: 10.12777/ijse.6.1.24-30

The effect of maximum normal impact load, absorbed energy and contact impulse on the impact craters volume/depth of DLC coating under repetitive impacts

Recently, the requirements for measuring dynamic responses have become severe and varied in many industrial and research applications such as material testing, model analysis and crash testing1). Surface degradation often occurs due to this dynamic response. This phenomenon also appears in the DLC coatings material. In this present work, a self-developed horizontal impact tester can provides this type of response, which gives an effect to the impact craters volume/depth of DLC coating