An in-depth Experimental Investigation of the Outdoor Performance of Wafer and Thin Film PV Technologies in a Tropical Climate

The photovoltaics (PV) industry is booming at an impressive rate. Knowledge of the outdoor perfor-mance of different PV technologies under different climatic conditions is becoming increasingly im-portant for all stakeholders. The aim of this research was to perform the outdoor characterisation of three PV technologies in a tropical climate and evaluate their performances with the aid of a set of key performance indicators. An innovative energy autonomous outdoor test facility has been used to measure the weather conditions and the IV curves of mono-Si, poly-Si and CIGS PV modules. Each IV curve was sampled within less than a second, for every 10 minutes, between sunrise and sunset for a whole year, representing a data set of around 28,000 IV curves of 240 points each. The variations of current, voltage and power were thoroughly studied for changes in temperature and irradiance. This paper reports the variations of temperature coefficients of current, voltage and power with the inten-sity of light. While PV module documentation only present the temperature coefficients of the short circuit current and open circuit voltage at Standard Test Conditions, this paper additionally provides highly valuable information to PV system designers on the variation of these coefficients in the field. The research is also the first to report the variations of the fill factor with temperature and irradi-ance. In general, the wafer technologies were found to have a better performance than the thin film technology. Moreover, the open-circuit temperature coefficient was found to improve for higher irra-diances only for the wafer technologies, while that for the thin-film technology experienced a degrada-tion. The temperature coefficient of current for the mono-Si module was found to be positive at low irradiance levels, but negative at higher irradiance levels.

An Isolated and Behind-the-Scenes Work Called Conservation

Conservation is a type of work which requires specific skills, a lengthy experience, particular infrastructures, and arguably extensive time and money. In fact, preserving collections by managing all the aspects required is an important and mandatory task. However, as a developing country in tropical climate, Indonesia is still in a phase where financial aid, skillful experts, and moral support for preserving the cultural heritage are much less than needed. As a result of complex organizational dynamics, building a formal partnership for frequent collaborative conservation work between archives, libraries, and museums nevertheless is far from simple. On the other hand, engaging the community to participate in the practice is particularly challenging due to the nature of conservation work as an isolated activity within an exclusive ecosystem. This chapter aims to discuss whether developing community engagement and collaboration between LAM can serve as an alternative support to constructively improve current conditions and cope with the aforementioned issues.

Analysis of culling reasons during the breeding cycle and lifetime performance: The strategy to remove crossbred Landrace and Large White sows under tropical climate

Background and Aim: Sow culling is an important practice in commercial swine production because it is directly associated with the economic efficiency of the breeding herd. This study was conducted to analyze the reasons for sow culling and quantify the factors affecting culling in crossbred Landrace and Large White sows under tropical climate. Materials and Methods: A total of 4887 culled sows from one parent stock farm located in Ratchaburi province, Western Thailand, were examined in this study. Culling reasons were grouped into the following eight categories according to farm management: (1) Reproductive disorders, (2) old age, (3) low performance, (4) diseases, (5) lameness, (6) udder problems, (7) body condition, and (8) other illnesses. Logistic regression analysis was used to explore the relationship between culling sows and environmental factors. Effects of parity and season of culling were considered as fixed effects in a statistical model. Results: Descriptive statistics indicated the following factors accounting for sow removals: Old age (34.93%, n=1707), reproductive disorders (29.32%, n=1433), low performance (12.62%, n=617), lameness (12.56%, n=614), diseases (4.8%, n=235), body condition (4.68%, n=229), udder problems (0.79%, n=39), and other illnesses (0.26%, n=13). Parity and season of culling were also found to have a significant effect on sow culling (p<0.05). The majority of culling sows in this population were of old age and high parity. Conclusion: This study indicated that the purposeful culling of sows on this farm was within the targeted range. However, the incidence of reproductive disorders was too high and required further investigations.

Comparison of ITU models performance in predicting Malaysia′s tropical Rainfall Rate and Rain Attenuation at 26GHz mm-wave propagation

Comparative study of the performance of different ITU model in predicting Malaysia tropical climate properties.

Comparison of ITU models performance in predicting Malaysia′s tropical Rainfall Rate and Rain Attenuation at 26GHz mm-wave propagation

Comparative study of the performance of different ITU model in predicting Malaysia tropical climate properties.

Global strong solutions and large time behavior of 2D tropical climate model with zero thermal diffusion

In this article, we study the global well-posedness and large-time behaviors of solutions to the two-dimensional tropical climate system with zero thermal diffusion for a small initial data in the whole space. The main approaches include high and low frequency decomposition method and exploiting the structure of system (1) to obtain the estimates of thermal dissipation. We utilize the time decay properties of the kernels to a linear differential equation to obtain the decay rates of solutions of the low frequency part and the decay property of exponential operator for the high frequency part. The key ingredient here is the explicit large-time decay rate of solutions.