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Conventional time series modeling may not satisfy the model validity for short-period time series data. In this study, we apply the Kernel Variant Multi-Way Principal Component Analysis (KMPCA) to cluster multivariate time series data which havemultiple dimensions with auto- and cross-correlations. We then check whether this method works well in clustering those data by employing simulation for generalization. Two simulation studies with two different mean structures with nine combinations of auto- and cross-correlations were conducted. The results showed that KMPCA cluster two different mean structure groups over 90% success rates with an appropriate kernel function. We also found that when the mean structures are the same, auto-correlation, the number of temporal points, and the kernel function parameter have the statistically significant effects on clustering performance. The second and third order interaction effects with each of those factors also have effects on clustering success rates. Among the effects of the main factors, the kernel function parameter is the most critical factor to consider for obtaining better performance. A similar error structure may obstruct the clustering performance: strong cross-correlation, weak auto-correlation, and a larger number of temporal points. The paper also discussed some limitations of the KMPCA model and suggested directions for future research that could improve the model.

This paper examines how the macroeconomic environment affects the determinants of prepayment of mortgage loans from October 2004 to February 2020. For more accurate analysis, the authors define the timing of prepayment not only before the loan maturity but also at the time when 50% or more of the loan principal is repaid. The results show that, during the global financial crisis as well as the recent period of low interest rates, macroeconomic variables such as interest rate spreads and housing prices have a different effect compared to the normal situation. Also, significant explanatory variables, such as debt to income (DTI) ratio, loan amount ratio and poor credit score, have different effects depending on the macroenvironment. On the other hand, in all periods, the possibility of prepayment increases as comprehensive loan to value (CLTV) increases, and the younger the age, the shorter the loan maturity. The results suggest that, in the case of ultralong (40 years) mortgage loans recently introduced to support young people purchasing houses, the prepayment risk can be, at least partially, migrated by offsetting the increase in prepayment by young people and the decrease in prepayment due to long loan maturity. In addition, this study confirms that the accelerated time failure model compared to the logit model and COX proportional risk model has the potential to be more appropriate as a prepayment model for individual borrower analysis in terms of the explanatory power.

On January 3, 2005, Regulation SHO was implemented by the Securities and Exchange Commission, with the express purpose of updating short sale regulation by seeking to limit an abusive short selling practice known as naked short selling. The purpose of this paper is to examine the efficacy and impact of Regulation SHO in achieving this goal of reducing naked shorting.

Time series analysis using fixed effects regression, Fama‐French‐Carhart model, various parametric and non‐parametric tests. The paper tests a number of hypotheses regarding the effectiveness of Regulation SHO in controlling naked shorts/fails‐to‐deliver in the American stock markets.

Utilizing several models, the authors find strong evidence in the first 30 to 60 days after being identified by Regulation SHO as having excessive naked short positions, those securities on average experienced further significant negative abnormal returns, indicating the regulation was at best ineffective. This result is robust for a number of parametric and non‐parametric tests. Models also show a security identified by Regulation SHO as having an excessive short position may actually suggest a profitable trading strategy of continuing to short those stocks. The regulation was largely ineffective/insignificant in reducing naked shorting. In addition, results revealed that a profitable investment could be made by shorting stocks as they were identified by Regulation SHO as already having excessive outstanding failure positions.

This is the first paper, to the authors' knowledge, that considers whether SHO was effective and offers intuition as to reasons why it was not.

In recent years, deep learning and extended reality (XR) technologies have gained popularity in the built environment, especially in construction engineering and management. A significant amount of research efforts has been thus dedicated to the automation of construction-related activities and visualization of the construction process. The purpose of this study is to investigate potential research opportunities in the integration of deep learning and XR technologies in construction engineering and management.

This study presents a literature review of 164 research articles published in Scopus from 2006 to 2021, based on strict data acquisition criteria. A mixed review method, consisting of a scientometric analysis and systematic review, is conducted in this study to identify research gaps and propose future research directions.

The proposed research directions can be categorized into four areas, including realism of training simulations; integration of visual and audio-based classification; automated hazard detection in head-mounted displays (HMDs); and context awareness in HMDs.

This study contributes to the body of knowledge by identifying the necessity of integrating deep learning and XR technologies in facilitating the construction engineering and management process.

Information technology provides important support for on-site decision-making of field personnel. Most literature focuses on the technological aspects of decision-support systems, without fully understanding the information required for effective decision-making. This study aimed to formalize decision-makers’ requirements in terms of the major goals, decisions and information.

The situation awareness (SA) approach was applied through the goal-directed task analysis (GDTA) method, narrowing the scope to field managers’ decision-making during indoor construction activities. This method was based on a series of interviews to define, revise and validate the decision-making requirements for the given scope.

The study yielded 1,056 highly interrelated elements. The results indicate that the field manager’s overall goal is to execute and handoff work within the established deadlines, with the required quality, maximizing profits, within a safe work environment. The overall goal construes into five main goals regarding work progress, quality, costs, safety and communication. These goals include subgoals, decisions, and the information necessary to attain them, depicted in diagrams.

The findings allow enhancing the design of decision-support solutions by identifying information required for future developments and showing the interrelations between goals and information requirements that need to be addressed to present interfaces for effectively assisting on-site decision-making. Moreover, the results allow for the assessment of solutions regarding the sufficiency of information.

This is the first effort to fully understand the information required by field managers for on-site decision-making during indoor construction activities.

Knowledge sharing has entered the stage of knowledge payment with the typical models of paid Q&A, live session, paid subscription, course column and community service. Numerous knowledge suppliers have begun to pour into the knowledge payment market, and users' willingness to pay for premium content has increased. However, the academic research on knowledge payment has just begun.

In this paper, the authors searched several bibliographic databases using keywords such as “knowledge payment”, “paid Q&A”, “pay for answer”, “social Q&A”, “paywall” and “online health consultation” and selected papers from aspects of research scenes, research topics, etc. Finally, a total of 116 articles were identified for combing studies.

This study found that in the early research, scholars paid attention to the definition of knowledge payment concept and the discrimination of typical models. With the continuous enrichment of research literature, the research direction has gradually been refined into three main branches from the perspective of research objects, i.e. knowledge provider, knowledge demander and knowledge payment platform.

This paper focuses on discussing and sorting out the key research issues from these three research genres. Finally, the authors found out conflicting and contradictory research results and research gaps in the existing research and then put forward the urgent research topics.

The purpose of this paper is to identify sexual health information needs and the cognitive and affective factors correlated with the best answer chosen by social Q&A users.

The study collected questions and answers regarding sexual health information on a social Q&A site, and analyzed the questions and a paired sample composed of best and non-best answers (n=480).

The main information needs of consumers are human development, sexual behavior, and sexual health. Best answers are more likely to include both cognitive (higher level of readability, risky information, social norms) and affective factors (empathy, positive/negative feelings, and optimistic information) than non-best answers.

The study illuminates the roles of social Q&A as a unique platform to discuss sensitive health topics due to the fact that consumers use such social media sites as critical complementary health information sources.

If health information providers develop information with the factors that the study suggests, not only will it be more adopted by consumers, but it will also ameliorate the quality concerns about online health information.

Previous studies only investigated the most prevalent factors, rather than the most effective ones, which have a greater influence on best answer selection. This study compares the best answers and the non-best answers to overcome the limitations of the previous studies. Above all, the study applied the persuasion concepts to address the cognitive and affective perspectives to the answer evaluations of social Q&A.

As an increasing number of users have acquired information across the web and mobile platforms for social question and answering (Q&A), it is of interest to explore whether there are differences in social Q&A usages between the two platforms. The purpose of this paper is to compare web and mobile platforms of a social Q&A service from the user’s perspective in terms of three dimensions, namely, demographics, individual-based constructs, and information-based constructs.

Because Zhihu.com is one of the most popular social Q&A sites in China, the authors used online questionnaires to investigate its users’ perceptions of these three dimensions. From January to March 2016, the authors obtained 278 valid responses in total through snowball and convenient sampling. Collected data are analyzed through descriptive statistics and inferential statistics.

The results indicate that there exist significant differences between web users and mobile users on Zhihu.com in terms of gender, affinity, and information seeking. More specifically, compared to the male users, more female users rely on the mobile platform to access the information service; mobile users perceive higher affinity with Zhihu.com than web users; and mobile users perceive higher information-seeking intention than web users do.

Regarding the theoretical aspect, this study proposes a conceptual framework for comparison between the web and mobile platforms of social Q&A from the user’s perspective. Regarding the practical aspect, the comparative results of this study could give social Q&A service providers useful information about users’ differences between web and mobile platforms of social Q&A services.

Discusses the 6th ITCRR, its breadth of textile and clothing research activity, plus the encouragement given to workers in this field and its related areas. States that, within the newer research areas under the microscope of the community involved, technical textiles focuses on new, ‘smart’ garments and the initiatives in this field in both the UK and the international community at large. Covers this subject at length.

This paper focuses on the evolution of and changes in French colonial architectural designs over time in terms of the use of vernacular architectural features of Vietnam.

It first examines the underlying principles of spatial compositions behind traditional vernacular architecture, thus revealing vernacular architectural values that have survived from the past. Styles of vernacular houses differ by region; thus, their unique spatial characteristics are analyzed by selecting the typical houses in each region. The study also illuminates ecological features and technical norms tailored to the local climate and Vietnamese traditional architecture. It examines how local and regional characters of vernacular houses affect the developments and changes in the French colonial public buildings in Vietnam, forming an identity that represents an eclectic Indochina style with the adaptation of local discourses on climate.

The Vietnamese have developed unique architectural styles that are inextricably linked to their identities, cultures, climates and livelihoods – for example, vernacular houses. Although at the beginning of the colonial period, the French imported their styles, decorations and details, which were foreign to the Vietnamese, later, they perhaps realized that such direct import was no longer suitable for the natural and socio-cultural situation of the colony. Toward the end of the colonial period, it is noticeable that French colonial architects gradually started using local design principles.

Although many existing buildings can be further added for the discussion, we limit a few cases, due to the length of the paper.

This paper proves that toward the end of the colonial period, colonial architecture in Vietnam became increasingly localized, adapting to the local environment and climate. The buildings during the period were gradually associated with Vietnamese culture and sentiment.

Although few papers deal with the vernacular architecture in Vietnam with regard to local climate and regional characteristics, there are no paper that related the vernacular Vietnamese houses to influence the French colonial designs in Vietnam. Therefore the paper has value and significance.