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Silicon photovoltaics technology has drawbacks of high cost and power conversion efficiency. In order to extract the maximum output power of the module, maximum power point (MPP) is used by implying the nonlinear behavior of I-V characteristics. Different techniques are used regarding maximum power point tracking (MPPT). The paper aims to review the techniques of MPPT used in PV systems and review the comparison between Perturb and Observe (P&O) method and incremental conductance (IC) method that are used to track the maximum power and gives a comparative review of all those techniques.

A study of MPPT techniques for photovoltaic (PV) systems is presented. Matlab Simulink is used to find the MPP using P&O simulation along with IC simulation at a steady temperature and irradiance.

MATLAB simulations are used to implement the P&O method and IC method, which includes a PV cell connected to an MPPT-controlled boost converter. The simulation results demonstrate the accuracy of the PV model as well as the functional value of the algorithms, which has improved tracking efficiency and dynamic characteristics. P&O solution gave 94% performance when configured. P&O controller has a better time response process. As compared to the P&O method of tracking, the incremental conductance response rate was significantly slower.

In PV systems, MPPT techniques are used to optimize the PV array output power by continuously tracking the MPP under a variety of operating conditions, including cell temperature and irradiation level.

As evident from the literature review, the research on cyber security performance is centered on security metrics, maturity models, etc. Essentially, all these are helpful for evaluating the efficiency of cyber security organization but what matters is how the factors of internal efficiency affect the business performance, i.e. the external effectiveness. The purpose of this research paper is to derive the factors of internal efficiency and external effectiveness of cyber security and develop impact model to identify the most and least preferred parameters of internal efficiency with respect to all the parameters of external effectiveness.

There are two objectives for this research: Deriving the factors of internal efficiency and external effectiveness of cyber security; Developing a model to identify the impact of internal efficiency factors on the external effectiveness of cyber security since there is not much evidence of research in defining the factors of internal efficiency and external effectiveness of cyber security, the authors have chosen grounded theory methodology (GTM) to derive the parameters. In this study emic approach of GTM is followed and an algorithm is developed for administering the grounded theory research process. For the second research objective survey methodology and rank order was used to formulate the impact model. Two different samples and questionnaires were designed for each of the objectives.

For the objective 1, 11 factors of efficiency and 10 factors of effectiveness were derived. These are used as independent and dependent variable respectively in the later part of the research for the second objective. For the objective 2 the impact models among independent and dependent variables were formulated to find out the following. Most and least preferred parameters lead to internal efficiency of cyber security organization to identify the most and least preferred parameters of internal efficiency with respect to all the parameters external effectiveness.

The factors of internal efficiency and external effectiveness constructed by using grounded theory cannot remain constant in the long run, because of dynamism of the domain itself. Over and above this, there are inherent limitations of the tools like grounded theory, used in the research. Few important limitations of GTM are as below in grounded theory, it is comparatively difficult to maintain and demonstrate the rigors of research discipline. The sheer volume of data makes the analysis and interpretation complex, and lengthy time consuming. The researchers’ presence during data gathering, which is often unavoidable and desirable too in qualitative research, may affect the subjects’ responses. The subjectivity of the data leads to difficulties in establishing reliability and validity of approaches and information. It is difficult to detect or to prevent researcher-induced bias.

The internal efficiency and external effectiveness factors of cyber security can be further correlated by the future researchers to understand the correlations among all the factors and predict cyber security performance. The grounded theory algorithm developed by us can be further used for qualitative research for deriving theory through abstractions in the areas where there is no sufficient availability of data. Practitioners of cyber security can use this research to focus on relevant areas depending on their respective business objective/requirements. The models developed by us can be used by the future researchers to for various sectoral validations and correlations.

Though the financial costs of a cyber-attack are steep, the social impact of cyber security failures is less readily apparent but can cause lasting damage to customers, employees and the company. Therefore, it is always important to be mindful of how the impact of cyber security affects society as well as the bottom line when they are calculating the potential impact of a breach. Underestimating either impact can destroy a brand. The factor of internal efficiency and external effectiveness derived by us will help stakeholder in focusing on relevant area depending on their business. The impact model developed in this research is very useful for focusing a particular business requirement and accordingly tune the efficiency factor.

During literature study the authors did not find any evidence of application of grounded theory approach in cyber security research. While the authors were exploring research literature to find out some insight into the factor of internal efficiency and external effectiveness of cyber security, the authors did not find concrete and objective research on this. This motivated us to use grounded theory to derive these factors. This, in the authors’ opinion is one of the pioneering and unique contribution to the research as to the authors’ knowledge no researchers have ever tried to use this methodology for the stated purpose and cyber security domain in general. In this process the authors have also developed an algorithm for administering GTM. Further developing impact models using factors of internal efficiency and external effectiveness has lots of managerial and practical implication.

Targets set out by state institutions, with respect to supplying water to deprived communities, seem to be idealistic and not realistic. Study envisioned to assess challenges of financing water infrastructure projects, and determines the role of the state towards infrastructure development by holistically planning and engaging with the private sector.

The study adopted a quantitative approach, whereby a questionnaire survey was conducted among different stakeholders involved in water infrastructure projects in South Africa. Data gathered were analysed using percentages, mean item score and standard deviation.

The study revealed that most challenges affecting the success of the financing of water infrastructure projects in South Africa are corruption, hostility towards private participation, cost recovery constraints, high fiscal deficits by state government, unreliable planning and procurement processes, and a rapid increasing number of municipalities that lack technical and administrative capacity to plan implement, operate and maintain water assets.

This research paper investigates projects’ financing challenges with a broad inspection on the role of the public sector. The apparent role of the international structures such as OECD, IMF and World Bank had no influence in the study. From the findings, it is clear that the central government and state institutions lack the necessary resources to accelerate infrastructure development, water infrastructure in particular. The study, thus, recommends a complete expansion and development of state capacity as well as improved collaborations with the private sector to drive the success delivery of services to the public.

Improved and flexible regulations and legislative guidelines are required to ensure that both sectors fulfil their side of the bargain, with an ultimate goal of meeting the predetermined targets of supplying adequate water to the deprived communities.

Maintaining food safety techniques in the supply chain management require special food safety labelling techniques during distribution in the retail food industry. The food products have to be of good quality and labelling inbound, manufacturing, and outbound in the supply chain contributes to this aim. The purpose of this study is to evaluate how food safety labelling is managed in Vietnam’s retail food industry with a special focus on food in Ho Chi Minh City, Vietnam. Photography was used in an observational study conducted among five separate retail market chains all located in this city. In which ways are the applications of the developed food safety labelling techniques among three separate retail food markets similar and dissimilar being accounted for? The results show that the packaging and labelling in Big C, Aeon Citimart, and Giant using the symbols of food safety build trust for their customers. The Big C indicates guidelines for VietGAP and green labelling. Aeon Citimart indicates the name of the good, expiration date and instructions for use as well as guidelines for the government factor (VietGAP) to the food safety practices in the Vietnamese food retail sector.