• Title/Summary/Keyword: Review Features

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An Analysis of the Roles of Experience in Information System Continuance (정보시스템의 지속적 사용에서 경험의 역할에 대한 분석)

  • Lee, Woong-Kyu
    • Asia pacific journal of information systems
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    • v.21 no.4
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    • pp.45-62
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    • 2011
  • The notion of information systems (IS) continuance has recently emerged as one of the most important research issues in the field of IS. A great deal of research has been conducted thus far on the basis of theories adapted from various disciplines including consumer behaviors and social psychology, in addition to theories regarding information technology (IT) acceptance. This previous body of knowledge provides a robust research framework that can already account for the determination of IS continuance; however, this research points to other, thus-far-unelucidated determinant factors such as habit, which were not included in traditional IT acceptance frameworks, and also re-emphasizes the importance of emotion-related constructs such as satisfaction in addition to conscious intention with rational beliefs such as usefulness. Experiences should also be considered one of the most important factors determining the characteristics of information system (IS) continuance and the features distinct from those determining IS acceptance, because more experienced users may have more opportunities for IS use, which would allow them more frequent use than would be available to less experienced or non-experienced users. Interestingly, experience has dual features that may contradictorily influence IS use. On one hand, attitudes predicated on direct experience have been shown to predict behavior better than attitudes from indirect experience or without experience; as more information is available, direct experience may render IS use a more salient behavior, and may also make IS use more accessible via memory. Therefore, experience may serve to intensify the relationship between IS use and conscious intention with evaluations, On the other hand, experience may culminate in the formation of habits: greater experience may also imply more frequent performance of the behavior, which may lead to the formation of habits, Hence, like experience, users' activation of an IS may be more dependent on habit-that is, unconscious automatic use without deliberation regarding the IS-and less dependent on conscious intentions, Furthermore, experiences can provide basic information necessary for satisfaction with the use of a specific IS, thus spurring the formation of both conscious intentions and unconscious habits, Whereas IT adoption Is a one-time decision, IS continuance may be a series of users' decisions and evaluations based on satisfaction with IS use. Moreover. habits also cannot be formed without satisfaction, even when a behavior is carried out repeatedly. Thus, experiences also play a critical role in satisfaction, as satisfaction is the consequence of direct experiences of actual behaviors. In particular, emotional experiences such as enjoyment can become as influential on IS use as are utilitarian experiences such as usefulness; this is especially true in light of the modern increase in membership-based hedonic systems - including online games, web-based social network services (SNS), blogs, and portals-all of which attempt to provide users with self-fulfilling value. Therefore, in order to understand more clearly the role of experiences in IS continuance, analysis must be conducted under a research framework that includes intentions, habits, and satisfaction, as experience may not only have duration-based moderating effects on the relationship between both intention and habit and the activation of IS use, but may also have content-based positive effects on satisfaction. This is consistent with the basic assumptions regarding the determining factors in IS continuance as suggested by Oritz de Guinea and Markus: consciousness, emotion, and habit. The principal objective of this study was to explore and assess the effects of experiences in IS continuance, with special consideration given to conscious intentions and unconscious habits, as well as satisfaction. IN service of this goal, along with a review of the relevant literature regarding the effects of experiences and habit on continuous IS use, this study suggested a research model that represents the roles of experience: its moderating role in the relationships of IS continuance with both conscious intention and unconscious habit, and its antecedent role in the development of satisfaction. For the validation of this research model. Korean university student users of 'Cyworld', one of the most influential social network services in South Korea, were surveyed, and the data were analyzed via partial least square (PLS) analysis to assess the implications of this study. In result most hypotheses in our research model were statistically supported with the exception of one. Although one hypothesis was not supported, the study's findings provide us with some important implications. First the role of experience in IS continuance differs from its role in IS acceptance. Second, the use of IS was explained by the dynamic balance between habit and intention. Third, the importance of satisfaction was confirmed from the perspective of IS continuance with experience.

The Traditional Garden Conservation Techniques through Partial Restoration Case - Focusing on the Palace Garden Sites of Korea, China and Japan - (일부 복원 사례를 통해 본 전통정원 보존기법 - 한·중·일 궁궐정원 유적을 중심으로 -)

  • Kim, Dong-Hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.1
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    • pp.28-35
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    • 2020
  • This study aims to analyze restoration techniques of traditional garden sites targeted Korean, Chinese, Japanese palace garden. Restoration was divided into the restore foundation and restore individual elements depending on the residual state of the actual garden features. And derived characteristics that should be considered by conservation techniques. The results are as follows; First, the Wanfo Pavilion Area in Beihai Park where the foundation and foundation stones were restored based on the relevant literature and comparative analysis. The Archaeological Site in Gwanbuk-ri, Buyeo restored only the remaining structures of the ponds, waterways and large buildings among the areas where the excavation was completed. The Second Daigokuden Garden in Heijokyo Palace restored building sites and foundation, and installed poles and piles so that the area of the Second Daigokuden Garden could be known. Second, Donggung Palace and Wolji Pond, Gyeongju where the restoration of individual elements was made, preemptively restored the remains of traditional gardens based on pond garden estuaries and feedbacks that were confirmed through initial excavation. Huanghuazhen Area in Yuanmingyuan Garden was restored based on Western copper plate prints and related records, but further data found after the restoration confirmed that it was restored differently than it is now. East Palace Garden in Heijokyo Palace covered existing features with soil and restored buildings on them. Typical garden elements such as landscape stone and waterways were preserved and exposed. Third, foundation restore is a case in which the base is identified through the current state of the traditional garden site, it is important to restore the foundation first and secure the territoriality when there is no restoration plan for the elevation structure or size of the garden relics. Restoration of individual garden elements requires careful examination of the literature by limiting the restoration of objects that can be restored through the examination of the literature for each element, such as some buildings or facilities in the traditional garden site.

Clinical Manifestations of 15 Cases of Pulmonary Sequestration (폐격리증 15예의 임상양상에 관한 고찰)

  • Park, Kwang-Joo;Kim, Eun-Sook;Kim, Hyung-Jung;Chang, Joon;Ahn, Chul-Min;Kim, Sung-Kyu;Lee, Won-Young;Kim, Sang-Jin;Lee, Doo-Yun
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.2
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    • pp.401-408
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    • 1997
  • Background : Pulmonary sequestration is a rare congenital malformation, which is manifested by formation of nonfunctioning lung tissue lacking normal communication with the tracheobronchial tree. The preoperative diagnostic rate has been relatively low, and without consideration of pulmonary sequestration, unexpected bleeding from aberrant vessels may be a serious problem during the operation. The purpose of our study is to describe the clinical features of pulmonary sequestration based on a review of 15 cases treated by operation. Method : Fifteen patients with pulmonary sequestration who had undergone surgical treatment from 1991 through May 1996 at Yongdong Severance Hospital and Severance Hospital were reviewed retrospectively. Results : The mean age of the patients was 22.5 years (range 5~57), and male to female ratio was 9 : 6. Clinical presentations varied from recurrent respiratory infections such as fever, cough, and sputum or chest pain to no symptom. The chest simple X-rays showed multicystic shadow(10/15) and solid mass-like shadow(5/15). The chest CT scans, done in twelve cases, showed multicystic lesion with or without lung infiltration(8/12), solid mass-like lesion(4/12), The chest MRIs, done in three cases, revealed the aberrant arteries originating from descending aorta(2/3). Aortograms, done in four cases, showed the aberrant arteries originating from descending thoracic aorta(2/4), abdominal aorta(I/4), and intercostal artery(1/4). and the venous returns were via the pulmonary veins. Pulmonary sequestration was considered preoperatively in six patients of fifteen. Other preliminary diagnosis were lung tumor(3/15), lung abscess(21/15), bronchiectasis(2/15), and mediastinal tumor(2/15). In the operative findings, twelve cases were of intralobar type and three cases of extralobar type. The left lower lobe was most often affected(9/15) and one extralobar sequestration was in the pericardium. The aberrant arteries originated from descending thoracic aorta(6/15), abdominal aorta(1/15), internal thoracic arteries (2/15), intercostal artery(1/15), pericardiophrenic artery(1/15), but in four cases, the origins could not be defined. There was no mortality or complication postoperatively. Conclusion : In our study, preoperative diagnostic rate was relatively low, and clinical features were similar to previous reports. Preoperative vigorous diagnostic approach including aortography is strongly advocated not only for its diagnostic value, but also for accurate localization of the aberrant vessels, which is major concern to surgical procedure.

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Clinical Features of Oromandibular Dystonia (하악운동이상증의 임상양태)

  • Kang, Shin-Woong;Choi, Hee-Hoon;Kim, Ki-Suk;Kim, Mee-Eun
    • Journal of Oral Medicine and Pain
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    • v.36 no.3
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    • pp.169-176
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    • 2011
  • Oromandibular dystonia (OMD) is a form of focal dystonia that affects the masticatory, facial and lingual muscles in any variety of combinations, which results in repetitive involuntary and possibly painful jaw opening, closing, deviation or a combination of these movements. This study aimed to investigate clinical features and treatment type of OMD patients. By retrospective chart review, the study was conducted to consecutive OMD patients who visited a department of Oral Medicine and Orofacial Pain Clinic in a university dental hospital during Aug 2007 to Apr 2010. 78 OMD patients were identified with female preponderance (M:F=1:3.6) and a mean age of 72 years. Their mean duration of OMD was about 10 months. The most common chief complaints at the first visit was jaw ache, followed by uncontrolled, repetitive movement of the jaw and/or oral tissues, pain in the oral region(p=0.000). The most common subtype of OMD was lateral jaw-deviation dystonia, followed by combination and jaw-closing dystonia(p=0.001). While no apparent cause was recognized in over 60% of the OMD patients, peripheral trauma including dental treatment such as prosthetic treatment and extraction was the most frequently reported as precipitating factor(p=0.000). Medication was the 1st line therapy for our patients and anxiolytics such as clonazepam was given to most of them. Based on the results of this study, OMD is the disease of the elderly, particularly of women and causes orofacial pain and compromises function of orofacial region. Some patients considered dental treatment a precipitating factor. Dentists, therefore, should have knowledge of symptoms and treatment of OMD.

A Brief Review of Soil Systematics in Germany (독일 토양분류체계 소개)

  • Kim, Rog-Young;Sung, Jwa-Kyung;Kim, Seok-Cheol;Jang, Byoung-Choon;Sonn, Yeon-Kyu
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.1
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    • pp.113-118
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    • 2010
  • Due to diverse soil-forming environments and different purposes of the soil classification, numerous soil classification systems have been developed worldwide. The World Reference Base for Soil Resources (WRB) and the Soil Taxonomy of the United States are well-known in Korea. However, the German Soil Systematics based on somewhat different principles from the two former systems is little-known. The objective of this paper is therefore to give a short overview of the principles of the German Soil Systematics. The German Soil Systematics consists of a six-level hierarchical structure which comprises soil divisions, soil classes, soil types, soil subtypes, soil varieties, and soil subvarieties. Soils in Germany are firstly classified into one of four soil divisions according to the soil moist regime: terrestrial soils, semi-terrestrial soils, semi-subhydric/subhydric soils, and peats. Terrestrial soils are subdivided into 13 soil classes based on the stage of soil formation and the horizon differentiation. Semi-terrestrial soils are differentiated into four classes regarding the source of soil moist: groundwater, freshwater, saltwater, and seaside. Semi-subhydric/subhydric soils are subdivided into two classes: semi-subhydric and subhydric soils. Peats are classified into two classes of natural and anthropogenic origins. Classes can be compared to orders of the U.S. Taxonomy. Classes are subdivided into 29 soil types with regard to soil forming-processes for terrestrial soils, into 17 types with regard to the soil formation for semi-terrestrial soils, into five types with regard to the content of organic matter for semi-subhydric/subhydric soils, and also into five types with regard to peat-forming processes for peats. The soil mapping units in Germany are types, which can be additionally subdivided into ca. 220 subtypes, several thousands of varieties and subvarieties using detailed nuances of morphologic features of soil profile. Soil types can be compared to great groups of the U.S. Taxonomy.

A Study on Clinical Features and Pharmacologic Treatment Outcomes of Patients with Trigeminal Neuralgia (삼차신경통의 임상 소견과 약물 치료에 관한 연구)

  • Ko, Yu-Jeong;Kim, Kyun-Yo;Hur, Yun-Kyung;Choi, Jae-Kap
    • Journal of Oral Medicine and Pain
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    • v.34 no.2
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    • pp.207-216
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    • 2009
  • Trigeminal neuralgia is defined "a sudden, usually unilateral, severe, brief, stabbing, recurrent pain in the distribution of one or more branches of the fifth cranial nerve". The initial treatment of choice for trigeminal neuralgia is medical therapy. In patients with medically intractable pain or intolerable medication side effects, invasive therapeutic approaches are often necessary. Based on the amount of evidence and estimated efficacy, carbamazepine is the drug of choice in the management of trigeminal neuralgia. In case of insufficient or no response to carbamazepine, second-line drugs can be added. In this study, the author tried to review and analyzed the cases of 90 patients whom had visited for treatment of trigeminal neuralgia at the Department of Oral Medicine, Kyungpook National University Hospital from 2003 to 2008. The results were as follows: 1. Trigeminal neuralgia was significantly more common with advancing age, and nearly twice as common in women than men (ratio of 2.1:1) 2. The maxillary branch of the trigeminal nerve involved most often (51.1%), and the right side of the face is affected more commonly than the left (ratio of 2.9:1). 3. 85(94.4%) patients had experiences visiting medical or dental specialties before being referred to the Department of Oral Medicine. 4. 40(44.4%) patients with trigeminal neuralgia had systemic diseases. 5. Treatment with carbamazepine monotherapy was satisfactory initially in 69(76.7%) the patients, and the mean daily dose of carbamazepine was 402.9mg. On the other hand, 16(17.8%) patients expressed effectiveness after combination therapy of carbamazepine and other drugs. 6. Of the 69 patients who had a good initial response to carbamazepine monotherapy, 18 patients became resistant, so that combination therapy of carbamazepine and other drugs were necessary. 7. 54(60%) patients developed side effects such as dizziness, drowsiness, nausea, vomiting, blood dyscrasias, skin rash and constipation, and 11 of the patients decided to stop tmedicaion due to side effects.

A Study on the Interactive Narrative - Focusing on the analysis of VR animation <Wolves in the Walls> (인터랙티브 내러티브에 관한 연구 - VR 애니메이션 <Wolves in the Walls>의 분석을 중심으로)

  • Zhuang Sheng
    • Trans-
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    • v.15
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    • pp.25-56
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    • 2023
  • VR is a dynamic image simulation technology with very high information density. Among them, spatial depth, temporality, and realism bring an unprecedented sense of immersion to the experience. However, due to its high information density, the information contained in it is very easy to be manipulated, creating an illusion of objectivity. Users need guidance to help them interpret the high density of dynamic image information. Just like setting up navigation interfaces and interactivity in games, interactivity in virtual reality is a way to interpret virtual content. At present, domestic research on VR content is mainly focused on technology exploration and visual aesthetic experience. However, there is still a lack of research on interactive storytelling design, which is an important part of VR content creation. In order to explore a better interactive storytelling model in virtual reality content, this paper analyzes the interactive storytelling features of the VR animated version of <Wolves in the walls> through the methods of literature review and case study. We find that the following rules can be followed when creating VR content: 1. the VR environment should fully utilize the advantages of free movement for users, and users should not be viewed as mere observers. The user's sense of presence should be fully considered when designing interaction modules. Break down the "fourth wall" to encourage audience interaction in the virtual reality environment, and make the hot media of VR "cool". 2.Provide developer-driven narrative in the early stages of the work so that users are not confused about the ambiguous world situation when they first enter a virtual environment with a high degree of freedom. 1.Unlike some games that guide users through text, you can guide them through a more natural interactive approach that adds natural dialog between the user and story characters (NPC). Also, since gaze guidance is an important part of story progression, you should set up spatial scene user gaze guidance elements within it. For example, you can provide eye-following cues, motion cues, language cues, and more. By analyzing the interactive storytelling features and innovations of the VR animation <Wolves in the walls>, I hope to summarize the main elements of interactive storytelling from its content. Based on this, I hope to explore how to better showcase interactive storytelling in virtual reality content and provide thoughts on future VR content creation.

The Materials on Korean Folk Religions in the Encyclopedic Literatures of Late Joseon Dynasty (조선후기 유서류(類書類)에 나타난 민속종교 자료)

  • Suh, Young-Dae
    • Journal of Korean Historical Folklife
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    • no.33
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    • pp.31-72
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    • 2010
  • At first, I extract materials on folk religion from four encyclopedic literatures of late Chosun dynasty-Lee, Ji-Bong-Ryu-Seol(『芝峯類說』) by Soo-Kwang(李晬光), San-Lim-Kyung-Jae(『山林經濟』) by Hong, Man-Sun(洪萬選), Sung-Ho-Sa-Seol(『星湖僿說』) by Lee-Ik(李瀷), O-Ju-Yeon-Moon-Jang-Jun-San-Go(『五洲衍文長箋散稿』) by Lee, Kyu-Kyung(李圭景), and present these materials by tables. Second, I examined the contents and characters of these materials on folk religion. The conclusions from this research are as follows. ① There are common features and points of difference between these four encyclopedic literatures. One of common features are that all these four are encyclopedic works, but San-Lim-Kyung-Jae is more practical than another three. ② These encyclopedic literatures regard folk religion as a negative culture, because these literatures based on Confucianism. But they did not deny miraculous virtues of folk religion. ③ These encyclopedic literatures give us many informations on gods and spirits of Korean folk religion, i.e. city gods(城隍神)·Yup-Sin(업신)·spirits of disease, god Kim-Bu(金傅大王神)·god Jung-Duk-Yang(鄭得揚)·god of King Kuan-u(關王神)·god Bu-keun(付根神) etc. So I review these gods and spirits referenced in encyclopedic literatures. ④ These encyclopedic literatures show much interest in ghost in common. The reason of interest is that authors of these encyclopedic literatures are all scholars of Sung Confucianism and Sung Confucian was concern about ghost. The Sung Confucianism denied the ghost as personal being whom Korean folk religion regards to a kind of spirits. Instead of beliefs in ghost of folk religion, they insist on the ghost as Ki(氣), a kind of cosmic principle. But these encyclopedic literatures acknowledge some parts of folk religion's beliefs in ghost, because they admit the miraculous virtues of these parts. ⑤ There are many items on divination in these encyclopedic literatures. But they show dual attitude on divinations. The one is negative attitude to divinations on individual destiny and the other one is positive attitude to divinations on agriculture. ⑥ There are also many items on witchcrafts in these encyclopedic literatures. Through these items, I assumed pervasiveness of beliefs on witchcraft at that time. ⑦ Shamans, as religious specialist, are stand on a central position of Korean folk religion. So it is a matter of course that these encyclopedic literatures concerned on Korean shaman. As Confucians, authors of these encyclopedic literatures did not regards shamans as positive one. But they did not deny miraculous virtues of shamans. In spite of these encyclopedic literatures have negative view points to, and include false informations Korean folk religion, I would like to emphasis on importance of these encyclopedic literatures to understand Korean folk religions, especially Korean folk religions of late Yi Dynasty.

A Clinical Review of Primary Tracheal Carcinoma (원발성 악성기관종양의 임상적 고찰)

  • Ryu, Jeong-Seon;Cho, Hyun-Myung;Yang, Dong-Gyoo;Lee, Hong-Lyeol;Kim, Se-Kyu;Chang, Joon;Ahn, Chul-Min;Shin, Kye-Chul;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.4
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    • pp.766-775
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    • 1997
  • Background : Primary malignant tumors of the trachea are extremely rare entities and account for a mere 0.1 per cent of all malignancies of the respiratory tract. Because of vague localizing signs, symptoms and a usually negative routine chest film, the patients with tracheal tumors are often treated for asthma or chronic obstructive pulmonary disease for considerable period of time before correct diagnosis. Method : We have made a review of the 17 cases of primary tracheal tumors in recent 15 years. We reviewed the clinical features including history of smoking and respiratory symptoms, the official readings of initial routine chest film, the cytologic examination of sputum, the time of delay in diagnosis, and the response according to the therapeutic modalities. Results : Eight out of 9 patients with squamous cell carcinoma(SCC) were above 50 years old, five out of 6 patients with adenoid cystic carcinoma(ACC) were below 50 years old. The most common location of primary tracheal tumors was the upper one-third of trachea in 8 cases(47%). The most frequent symptoms were dyspnea in 13/17 cases(76%) and then stridor or wheezing, cough. and sputum in order. The routine chest roentgenographic examinations were not helpful to diagnose tracheal carcinoma and the cytologic examinations of sputums were helpful to diagnose tracheal carcinoma in only one case with adenocarcinoma. The mean times of delay in diagnosis of patients with sec and ACC were 5 months and 24.9 months respectively. We had bronchial asthma in 8 cases(47%) and tracheal tumors in 4 cases(23%) as initial clinical impression. Conclusion : We would like to perform more comprehensive diagnostic tools(high KVP technique, the fibroptic bronchoscopic examination, chest CT scan etc.) in patients who had the suggestive points for the tracheal tumorse(1. unexplained hemoptysis or hoarsness, 2. inspiratory wheezing or stridor, 3. wax and waning of dyspnea according to changes of position, 4. progressive asthmatics unresponsive to antiasthmatic therapy) and radical resection of tumor or external radiation therapy with curative aim as possible.

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Adenoviral Lower Respiratory Tract Infection of Children in Korea from 1990 Through 1998 (소아의 Adenovirus 하기도 감염증에 관한 연구 - 유행 양상과 임상 양상에 대하여 -)

  • Hong, Jung Youn;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.7 no.1
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    • pp.94-107
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    • 2000
  • Purpose : The purpose of this study is to know the clinical manifestations and the severity of adenoviral lower respiratory tract infections(LRTI) in Korean children. Methods : Adenoviral respiratory infection was diagnosed by viral culture in HEp-2 cell and indirect immunofluorescent technique with nasal aspirates. Isolated adenoviruses were typed by neutralization test. Retrospective chart review was done in patients with adenoviruses were typed by neutralization test. Retrospective chart review was done in patients with adenoviral lower respiratory tract infection, who were brought to Seoul National University Children's Hospital from November 1990 through February 1998. Results : Adenovirus was isolated in 87 cases. Of 84 cases serotyped, type 1 was recovered in 3 cases, type 2 in 13 cases, type 3 in 13, type 4 and 5 in 4 cases each other, type 6 in 1 cases, type 7 in 36 cases, type 11 in 1 case and the other types in 9 cases. Adenoviral lower respiratory infection occurred sporadically throughout the year but from November 1995 through February 1998, an outbreak of adenovirus type 7 lower respiratory infection was observed in number upto 36 case. The incidence of adenoviral infection peaked in young children between 6 months and 5 years of age and the mean age was 1 year 11 months old. There were 10 cases of mixed infection with another pathogen. Clinical diagnosis were pneumonia(88%), acute broncholitis(5.4%), acute tracheobronchitis(5.4%), croup(1.3%). The clinical features of adenoviral lower respiratory infection were severe especially in type 3 and 7 infections in aspect of fever duration, ventilator care. Extrapulmonary manifestations were gastrointestinal symptoms in 23 cases(31%), hepatomegaly in 36 cases(53%), seizure and mental alteration in 13 cases(20.3%). In chest radiographic findings, parahilar and peribronchial infiltration were in 49 cases(67%), hyperaeration in 21 cases(29%), atelectasis in 14 cases(19%), consolidation in 39 cases(53%) and bilateral pneumonic infiltration in 28 cases(38%). Among thirty six adenovirus type 7 LRTI, 15 patients(41.6%) had pleural effusion and 3 patients had chest tube insertion. Number of fetal cases related to adenovirus were 9 cases(12%) and fetal cases due to ventilatory failure were 7(11%). Conclusion : During 7 year period of studying adenoviral lower respiratory infection, we identified the serotypes of adenovirus. Among the serotypes, adenovirus type 7 were epidemically isolated. Adenovirus were isolated in severe lower respiratory infection of young children aged between 6 months and 5 years and related to death of the patients, especially when the patients had underlyng diseases or were infected by adenovirus type 7.

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