<span>Hydroxyapatite Ca<span>10<span>(PO<span>4<span>)<span>6<span>(OH)<span>2 <span>is a calcium phosphate compound having biocompatibility <span>properties. FTIR (Fourier Transform Infrared Spectroscopy) was used to determine the <span>characteristics of the hydroxyapatite group. Modeling the functional groups of hydroxyapatite <span>can be used to obtain vibrational frequencies and spring constants. Analysis of energy release <span>function is performed by calculating the dissociation energy. In this paper will be shown the <span>results of theoretical modeling of hydroxyl and phosphate using spring models. Modeling the <span>functional groups OH<span>- <span>obtained spring constant 524,4559 N/m and the absorption wave number <span>3497,5677 cm<span>-1<span>. Modelling functional groups PO<span>43-<span>obtained spring constant 612,2704 N/m <span>and the wave number 1085,2559 cm<span>-1 <span>absorption. The constant and absorption wave numbers <span>obtained are used to calculate the dissociation energy. OH<span>- <span>dissociation energy obtained by <span>566,5637 kJ/mol and the dissociation energy of PO<span>43- <span>is 567,6248 kJ/mol. Absorption wave <span>numbers are obtained in accordance with experimental results on sometrik stretch modes, and <span>the dissociation energy derived functional group is also close to the value of literature.</span></span></span></span></span></span></span></span></span></span></span></span><br /></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>

This research aims to determine the marketing stategy of Kedai Karya Online Shop in increaseasing sales and and to know the factors that influence the fluctuation of sales turnover in Kedai Karya Online Shop. Informants of this research is the owner of Kedai Karya Online Shop. Sources of data collected from interviews, documentation, and observation. Data analysis techniques using interactive analysis techniques include data reduction, data presentation, and conclusions. The results show that Kedai Karya Online Shop use e-marketing strategy that is product strategy, price, communication, and distribution. Factors that influence an increase in sales turnover are seasonal factors, innovation factors, and use of paid advertising. Then the factors that affect the decline in sales turnover is the lack of promotion.   Keyword : marketing, strategy, online shop, sales

The getting older of people age, the density of bone will be further reduced. The process speed of bone formation decreases progressively after reaching peak bone mass in the age range 25-30 years. The reduction in bone density is known as osteoporosis. This phenomenon occurs due to an interruption on remodelling bone due to some conditions. Therefore, this study is going to simulate the effect of mechanical stimuli on femur bone density using walking and standing mechanical stimuli. In this study, there are four stages passed. First, build the femur bone construction which consists of two layers (cortical and trabecular). Then input the properties of bone based on age (Young’s modulus and Poisson’s ratio). Then calculate the stress, strain and strain rate and calculate the bone density using thermodynamic equation of V. Klika and F. Marsik with Runge-Kutta method of 4th orde. The bone density given standing mechanical stimuli (1290 N) for age 25 is 0.7963 g/cm2 and walking mechanical stimuli (1741.5 N) is 1.0698 g/cm2. Then the bone density given standing mechanical stimuli (1200 N) for age 51 is 0.7703 g/cm2 and walking mechanical stimuli (1620 N) is 0.9885 g/cm2.

In this study, the researchers measured cicadas' sound waves, considering that cicadas are mostly found in rural areas. The intensity level meter (AMTAST AMF003) was used with time variations (9:00 JST; 12:00 JST; and 15:00 JST). Measurements of air temperature differences (Krisbow Temperature Humidity Data Logger) were also carried out, and weather conditions were also considered in data collection using satellite data from Himawari, Japan. The interpretation results of intensity level's trend measured at 3:00 pm JST were decreased concerning the changes in days. Meanwhile, the measurement at 09:00 am and 12:00 pm JST did not show a decrement concerning the changes in days (31 days in total). These results show that temperature changes (towards autumn) can affect the intensity level of sound waves. In addition, slightly different intensity levels can affect large changes in acoustic power or the produced sound.