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Clinical Characteristics of Elderly Patients with Pulmonary Tuberculosis (고령자 폐결핵에 대한 임상적 관찰)

  • Kim, Chung-Tae;Um, Hye-Suck;Lee, Hyang-Ju;Rhu, Nam-Soo;Cho, Dong-Il
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.4
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    • pp.432-440
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    • 2000
  • Background : The prevalence of pulmonary tuberculosis among the elderly is increasing in Korea and in the developed countries due to the increased elderly population and their predispositions to chronic disease, poverty and decreased immunity. To define the characteristics of pulmonary tuberculosis in the elderly, we evaluated the clinical spectrum of pulmonary tuberculosis. Method : We analyzed 92 patients retrospectively that were diagnosed as active pulmonary tuberculosis over the age of 65. The analysis involved patient's profiles, clinical manifestations, coexisting diseases, diagnostic methods, anti-TB medications and their side effects, and treatment outcomes. Results : The results were as follows : - 1) The ratio of male to female was 2.1:1(62:30 cases) 2) Chief complaints were a cough (47.8%), dyspnea (40.2%), sputum (38.0%), chest pain (12.0%), anorexia (10.9%), and fever (9.8%). 3) 38 (41.3%) of cases had a past history of pulmonary tuberculosis. 4) The coexisting diseases were : -COPD, 25 cases (27.2%); pneumonia, 17 cases (18.5%); DM. 13 cases (14.1%); and malignancy, 10 cases (10.9%). 5) The positivity of Mantoux test (5 TU, PPD-S) was 82.7%. 6) Pulmonary tuberculosis was diagnosed using the following methods : sputum AFB (Acid Fast Bacillus) smear 42.4%, sputum TB (M. Tuberculosis) culture 15.2%, sputum TB PCR (Polymerase Chain Reaction) 10.9%, bronchial washing AFB smear 2.1%, chest radiology only 25.0%. 7) Locations of radiologic lesions were RULF, 50 cases; RLLF, 50 cases, mostly, then LLLF ; 26 cases were leastly involved. 8) The coexisting tuberculosis were endobronchial TB(8.7%), TB pleurisy(7.6%) miliary TB(5.4%), intestinal TB(2.2%), renal TB(1.1%) 9) The proportion of treatment regimen with 1st line drug and 2nd line drug were 92.3% and 7.6%, respectively. 10) The outcome of treatment were as follows : cured 31.5%, expired 13.0%, no return 47.8%, follow-up now 7.6%. Conclusion : The pulmonary tuberculosis in the elderly has atypical patterns with chronic coexisting diseases. Therefore, the possibility of pulmonary tuberculosis should be considered in elderly patients with pulmonary symptoms.

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A Study on the Degree of Need of Human Structure and Function Knowledge in Clinical Nurses (기초간호자연과학의 인체구조와 기능 내용별 필요도에 대한 연구)

  • Choe, Myoung-Ae;Byun, Young-Soon;Seo, Young-Sook;Hwang, Ae-Ran;Kim, Hee-Seung;Hong, Hae-Sook;Park, Mi-Jung;Choi, Smi;Lee, Kyung-Sook;Seo, Wha-Sook;Shin, Gi-Soo
    • Journal of Korean Biological Nursing Science
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    • v.1 no.1
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    • pp.1-24
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    • 1999
  • The purpose of this study was to define the content of requisite human structure and function knowledge needed for clinical knowledge of nursing practice. Subjects of human structure and function were divided into 10 units, and each unit was further divided into 21 subunits, resulting in a total of 90 items. Contents of knowledge of human structure and function were constructed from syllabus of basic nursing subjects in 4 college of nursing, and textbooks published by nurse scholars prepared with basic nursing sciences. The degree of need of 90 items was measured with a 4 point scale. The subjects of this study were college graduated 136 nurses from seven university hospitals in Seoul and three university hospitals located in Chonnam Province, Kyungbook Province, and Inchon. They have been working at internal medicine ward, surgical ward, intensive care unit, obstetrics and gynecology ward, pediatrics ward, opthalmology ward, ear, nose, and throat ward, emergency room, rehabilitation ward, cancer ward, hospice ward, and their working period was mostly under 5 years. The results were as follows: 1. The highest scored items of human structure and function knowledge necessary for nursing practice were electrolyte balance, blood clotting mechanism and anticoagulation mechanism, hematopoietic function, body fluid balance, function of plasma, and anatomical terminology in the order of importance. The lowest scored items of human structure and function knowledge necessary for nursing practice was sexual factors of genetic mutation. 2. The highest order of need according to unit was membrane transport in the living unit, anatomical terminology in movement and exercise unit, mechanism of hormone function in regulation and integration unit, component and function of blood in oxygenation function unit, structure and function of digestive system in digestive and energy metabolism unit, temperature regulation in temperature regulation unit electrolyte balance in body fluid and electrolyte unit, concept of immunity in body resistance unit, and genetics terminology in genetics unit. The highest order of importance according to subunit was membrane transportation in cell subunit, classification of tissues in tissue unit, function of skin and skin in skin subunit, anatomical derivatives of the skeleton subunit, classification of joints in joint subunit, an effect of exercise on muscles in muscle subunit, function of brain in nervous system subunit, special sense in sensory subunit mechanism of hormone function in endocrine subunit, structure and function of female reproductive system in reproductive system unit, structure and function of blood in blood unit, structure of heart, electrical and mechanical function in cardiovascular system unit, structure of respiratory system in respiratory system subunit, structure and function of digestive system in digestive system subunit, hormonal regulation of metabolism in nutrition and metabolism subunit, function of kidney in urologic system subunit, electolyte balance in body fluid, electolyte and acid-base balance subunit. 3. The common content of human structure and function knowledge need for all clinical areas in nursing was structure and function of blood, hematopoietic function, function of plasm, coagulation mechanism and anticoagulation mechanism, body fluid, electrolyte balance, and acid-base balance. However, the degree of need of each human structure and function knowledge was different depending on clinical areas. 4. Significant differences in human structure and function knowledge necessary for nursing practice such as skin and derivatives of the skin, growth and development of bone, classification of joint, classification of muscle, structure of muscle, function of muscle, function of spinal cord, peripheral nerve, structure and function of pancrease, component and function of blood, function of plasma, structure and function of blood, hemodynamics, respiratory dynamics, gas transport, regulation of respiration, chemical digestion of foods, absorption of foods, characteristics of nutrients, metabolism and hormonal regulation, body energy balance were demonstrated according to the duration of work. 5. Significant differences in human structure and function knowledge necessary for nursing practice such as classification of tissue, classification of muscles, function of muscles, muscle metabolism, classification of skeletal muscles, classification of nervous system, neurotransmitters, mechanism of hormone function, pituitary and pituitary hormone, structure and function of male reproductive organ, structure and function of female reproductive organ, component and function of blood, function of plasma, coagulation mechanism and anticoagulation mechanism, gas exchange, gas transport, regulation of respiration, characteristics of nutrients, energy balance, function of kidney, concept of immunity, classification and function of immunity were shown according to the work area. Based on these findings, all the 90 items constructed by Korean Academic Society of Basic Nursing Science should be included as contents of human structure and function knowledge.

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A Study on the Restoration of the Wangheungsa Temple's Wooden Pagoda (왕흥사 목탑의 복원 연구)

  • Kim, Kyeong-Pyo;Sung, Sang-Mo
    • Journal of architectural history
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    • v.19 no.3
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    • pp.7-29
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    • 2010
  • The form of the Wangheungsa Temple's wooden pagoda site is that of the traditional form of the wooden pagodas constructed during the Baekjae Period. Likewise, it is an important ruin for conducting research on the form and type of the wooden pagodas constructed during the Baekjae Period. In particular, the method used for the installation of the central pillar's cornerstone is a new technique. The purpose of this research is to restore the ruin of the Wangheungsa Temple's wooden pagoda of the Baekjae Period that remains at the Wangheungsa Temple's wooden pagoda site. Until now, research conducted on the wooden pagoda took place mostly centered on the Hwangryongsa Temple's wooden pagoda. Meanwhile, the reality concerning Baekjae's wooden pagoda is one in which there were not many parallel cases pertain to the design for restoration. This research paper wants to conduct academic examination of the Wangheungsa Temple's wooden pagoda to organize the intention of design and design process in a simple manner. This research included review of the Baekjae Period's wooden pagoda related ruins and the review of the existing wooden pagoda ruin to analyze the wooden pagoda construction technique of the era. Then, current status of the Wangheungsa Temple's wooden pagoda site is identified to define the characteristics of the wooden pagoda, and to set up the layout format and the measure to estimate the size of the wooden pagoda in order to design each part. Ultimately, techniques and formats used for the restoration of the wooden pagoda were aligned with the wooden pagoda of the Baekjae Period. Basically, conditions that can be traced from the current status of the Wangheungsa Temple site excavation using the primary standards as the standard. Wangheungsa Temple's wooden pagoda was designed into the wooden pagoda of the Baekjae's prosperity phase. The plane was formed into $3{\times}3$ compartments to design into three tier pagoda. The height was decided by factoring in the distance between the East-West corridors, size of the compartment in the middle, and the view that is visible from above the terrace when entering into the waterway. Basically, the origin of the wooden structure format is based on the Goguryeo style, but also the linkage with China's southern regional styles and Japan's ancient wooden pagoda methods was factored in. As for the format of the central pillar, it looks as if the column that was erected after digging the ground was used when setting up the columns in the beginning. During the actual construction work of the wooden pagoda, central pillar looks as if it was erected by setting up the cornerstone on the ground. The reason that the reclaimed part of pillar that use the underground central cornerstone as the support was not utilized, was because the Eccentric Load of the central pillar's cornerstone was factored in the state of the layers of soil piled up one layer at a time that is repeated with the yellow clay and sandy clay and the yellow clay that were formed separately with the $80cm{\times}80cm$ angle at the upper part of the central pillar's cornerstone was factored in as well. Thus, it was presumed that the central pillar was erected in the actual design using the ground style format. It is possible to presume the cases in which the reclaimed part of pillar were used when constructed for the first time, but in which central pillar was installed later on, after the supplementary materials of the underground column is corroded. In this case, however, technique in which soil is piled up one layer at a time to lay down the foundation of a building structure cannot be the method used in that period, and the reclamation cannot fill up using the $80cm{\times}80cm$ angle. Thus, it was presumed that the layers of soil for building structure's foundation was solidified properly on top of the central pillar's cornerstone when the first wooden pagoda construction work was taking place, and that the ground style central pillar was erected on its upper part by placing the cornerstone once again. Wangheungsa Temple's wooden pagoda is significant from the structure development aspect of the Korean wooden pagodas along with the Hwangryongsa Temple's wooden pagoda. Wangheungsa Temple's wooden pagoda construction technique which was developed during the prosperity phase of the Baekjae Period is presumed to have served as a role model for the construction of the Iksan Mireuksa Temple's wooden pagoda and Hwangryongsa Temple's wooden pagoda. With the plan to complement the work further by excavating more, the basic wooden pagoda model was set up for this research. Wangheungsa Temple's wooden pagoda was constructed as at the Baekjae Kingdom wide initiative, and it was the starting point for the construction of superb pagoda using state of the art construction techniques of the era during the Baekjae's prosperous years, amidst the utmost interest of all the Baekjae populace. Starting out from its inherent nature of enshrining Sakyamuni's ashes, it served as the model that represented the unity of all the Baekjae populace and the spirit of the Baekjae people. It interpreted these in the most mature manner on the Korean peninsula at the time.

A Study on the Determinants of Luxuriousness: With Focus on Product Attributes and Luxuriousness (명품성의 결정요인에 관한 연구: 제품속성과 명품성을 중심으로)

  • Lim, JoongSik;Koh, InKon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.10 no.4
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    • pp.95-111
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    • 2015
  • This purpose of this study is to academically define what "luxury products" mean, and to clarify the cognitive structural relationship between product attributes and "luxuriousness" in relation to the determinant of luxuriousness that eventually affects the purchase intention of consumers. This study is also written under the theory that luxuriousness leads to benefits such as functional benefit, experiential benefit, symbolic benefit, and exclusive benefit; which all provide core values to consumers and serve as effect factors that influence the psychological satisfaction of consumers. The commonly discussed measure of the determinant of luxuriousness has often failed to adequately describe the reasons to why the consumers prefer luxury products. This study also aims to suggest a new path in how and what the consumers perceive as luxury products, and to conceptualize what luxuriousness means in the marketing perspectives on the background of a previous theory. The part of product attributes are divided in the following sections: the quality and design of functional cues and brands of symbolic cues, as well as prices. The part of the determinant of luxuriousness is divided in sections of superiority, scarcity, differentiation, and traditionality. Therefore, this study used the theoretical concept used in such common measures as well as 282 examples to empirically analyze the relationship between product attributes and luxuriousness of luxury products, and how such affect the purchase intentions of consumers. The survey used to aid this study targeted luxury product consumers regarding "B" brand of automobiles. Using the analysis through a structural equation model, the study draws a conclusion that in a relationship between product attributes and luxuriousness, quality(which is one of the functional cues) affects the facts of superiority, differentiation in a significant way, and design affects the factors of scarcity in a significant way. And brand(one of the symbolic cues) significantly affects the factors of traditionality within the luxuriousness factors, and price appeared to affect superiority and scarcity. Additionally, the brand of product attributes significantly affects purchase intention, and superiority and scarcity of luxuriousness affects purchase intention in a significant way. The structural concept of luxury and luxuriousness suggested in the study will provide the theoretical basis for building a new case study, and the determinants of luxuriousness in the marketing perspective will be a practical help for checking the consumers' psychological reasons for purchase.

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A Framework for Creating Inter-Industry Service Models in the Convergence Era (융합 서비스 모델 개발 방법론 및 체계 연구)

  • Kwon, Hyeog-In;Ryu, Gui-Jin;Joo, Hi-Yeob;Kim, Man-Jin
    • Asia pacific journal of information systems
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    • v.21 no.1
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    • pp.81-101
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    • 2011
  • In today's rapidly changing and increasingly competitive business environment, new product development in tune with market trends in a timely manner has been a matter of the utmost concern for all enterprises. Indeed, developing a sustainable new business has been a top priority for not only business enterprises, but also for the government policy makers accountable for the health of Its national economy as well as for decision makers in what type of organizations. Further, for a soft landing of new businesses, building a government-initiated industry base has been claimed to be necessary as a way to effectively boost corporate activities. However, the existing methodology in new service and new product development is not suitable for nurturing industry, because it is mainly focused on the research and development of corporate business activities instead of new product development. The approach for developing new business is based on 'innovation' and 'convergence.' Yet, the convergence among technologies, supplies, businesses and industries is believed to be more effective than innovation alone as a way to gain momentum. Therefore, it has become more important than ever to study a new methodology based on convergence in industrial quality new product development (NPD) and new service development (NDS). In this research, therefore, we reviewed any restrictions in the existing new product and new service development methodology and the existing business model development methodology. In doing so, we conducted industry standard collaboration analysis on a new service model development methodology in the private sector and the public sector. This approach is fundamentally different from the existing one in that ours focuses on new business development under private management. The suggested framework can be categorized into industry level and service level. First, in the industry level, we define new business opportunities In occurrence of convergence between businesses. For this, we analyze the existing industry at the industry level to identify the opportunities in a market and its business attractiveness, based on which the convergence industry is formulated. Also, through the analysis of environment and market opportunity at the industry level. we can trace how different industries are lined to one another so as to extend the result of the study to develop better insights into industry expansion and new industry emergence. After then, in the service level, we elicit the service for the defined new business, which is composed of private service and supporting service for nurturing industry. Private service includes 3steps: plan-design-do; supporting service for nurturing industry has 4 steps: selection-make environment- business preparation-do and see. The existing methodology focuses on mainly securing business competitiveness, building a business model for success, and offering new services based on the core competence of companies. This suggested methodology, on other hand, suggests the necessity of service development, when new business opportunities arise, in relation to the opportunity analysis of supporting service based on the clear understanding of new business supporting infrastructure optimization. Meanwhile, we have performed case studies on the printing and publishing field with the restrict procedure and development system to assure the feasibility and practical application. Even though the printing and publishing industry is considered a typical knowledge convergence industry, it is also known as a low-demand and low-value industry in Korea. For this reason, we apply the new methodology and suggest the direction and the possibility of how the printing and publishing industry can be transformed as a core dynamic force for new growth. Then, we suggest the base composition service for industry promotion(public) and business opportunities for private's profitability(private).

Therapeutic Effect of Anti-Rotavirus Chicken Egg Yolk Immunoglobulin(IgY) on Diarrhea by Infection of Rotavirus (로타바이러스 감염성 설사에 대한 항-로타바이러스 난황항체의 치료 효과)

  • Lim, In Seok;Lee, Ho Seok;Kim, Wonyong;Choi, Eung Sang;Jung, Dong Hyuk;Jung, Hoo Kil;Yun, Sung Seob;Chun, Ho Nam
    • Clinical and Experimental Pediatrics
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    • v.48 no.12
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    • pp.1354-1361
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    • 2005
  • Purpose : Rotavirus is an enteric pathogen that affects millions of children globally each year. But no specific therapy is available for the management of rotavirus diarrhea. Due to the clear need to define improved modality for treatment of rotavirus diarrhea, we evaluated the efficacy of antirotavirus IgY in the treatment of infants and children with gastroenteritis. Methods : First, the amount of viral particle in the stools of thirteen patients(seven were given IgY, 6 placebo) infected by rotavirus were evaluated for 3 days with the quantitative RT-PCR method. Second, 36 children with known rotavirus infection identified by ELISA or semi-quantitative RT-PCR were evaluated. We gave 5 g anti-rotavirus egg yolk daily in two equally divided doses for 3 days to two groups(an 18 IgY group and an 18 placebo group), respectively after parenteral consent. Daily vomiting frequency, stool frequency, oral intake and urine output were monitored for 3 days, and electrolyte and blood chemistry were checked at the first and third days. Results : First, in the placebo group, the amount of virus particles increased daily, but in the IgY group it decreased daily. Second, when IgY and placebos were given to children infected with rotavirus, diarrhea on the third day decreased significantly in the IgY group, compared with the placebo group. Conclusion : Treatment with antirotavirus immunoglobulin from immunized chicken's egg resulted in a decrease in the amount of viral particles in stools and diarrhea frequency in children. These results suggest that anti-rotavirus IgY is effective in the treatment of rotavirus gastroenteritis.

Clinical factors causing hyponatremia in patients with mucocutaneous lymph node syndrome (가와사끼병에서 저나트륨혈증의 관련인자에 대한 임상적 고찰)

  • Kim, Soo Yeon;Kim, Hyun Jung;Choi, Jun Seok;Huh, Jae Kyung
    • Clinical and Experimental Pediatrics
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    • v.52 no.3
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    • pp.364-369
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    • 2009
  • Purpose : Clinical and laboratory findings predict a severe outcome for mucocutaneous lymph node syndrome. This study aimed to define the clinical characteristics of Kawasaki disease (KD) patients with hyponatremia and to determine the factors associated with its development. Methods : Retrospective studies were performed on 114 KD patients who received an initial high-dose intravenous immunoglobulin (IVIG, single 2 g/kg/dose) within 10 days of fever onset from January 2006 to February 2008. These patients were divided into 2 groups. Group 1 consisted of 30 (26.3%) patients with hyponatremia, and group 2 consisted of 84 (73.6%) patients without hyponatremia. Clinical manifestations, laboratory results, and echocardiographic findings were compared between the groups. Results : Group 1 patients were more likely to have a coronary artery lesion (53.3% versus 20.2%, P=0.005) and suffered from diarrhea (41.3% versus 14.1%, P=0.007). There was a higher incidence of cardiovascular involvement in group 1 patients, including coronary dilatation (46.6%), valvular regurgitation (13.3%), pericardial effusion (6.7%) and medium-sized aneurysm (6.7%). There were no coronary aneurysms in group 2 patients. Serum C-reactive protein (CRP) was significantly higher in patients with hyponatremia ($12.2{\pm}7.79$ mg/dL versus $7.3{\pm}4.7$ mg/dL, P=0.003) and IVIG-resistant patients were more common in group 1 (13.3% versus 3.6%). Conclusion : These results indicate that hyponatremia in KD occurs in patients exhibiting severe inflammation and was significantly associated with the development of coronary disease. Further studies will be necessary to confirm the pathogenic mechanisms of hyponatremia in KD patients.

Subtalar Arthroscopy : Indication and Results (거골하 관절경 : 적응증과 그 결과)

  • Ahn, Jae-Hoon;Lee, Kwang-Won;Kim, Ha-Yong;Lee, Seung-Hun;Choy, Won-Sik;Kim, Seung-Kwon
    • Journal of the Korean Arthroscopy Society
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    • v.11 no.1
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    • pp.39-44
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    • 2007
  • Purpose: To evaluate the results of subtalar arthroscopy and to define the indications for the procedure. Materials and Methods: Fifty-four patients were followed up for more than 1 year after subtalar arthroscopy. The mean age was 40 years, and the mean follow-up period was 18 months. Preoperative diagnoses included sinus tarsi syndrome in 19 cases, degenerative arthritis in 13 cases, calcaneal fracture in 10 cases, arthrofibrosis in 5 cases, os trigonum syndrome in 3 cases, talar fracture in 3 cases, talocalcaneal coalition in 3 cases and calcaneal tumor in 1 case. Clinically AOFAS ankle-hindfoot scale and satisfaction of the patients were evaluated. Results: There were 23 synovectomies, 13 subtalar fusions, 11 diagnostic arthroscopies, 5 adhesiolyses, 4 loose body removals, 3 excisions of os trigonum and 1 arthroscopic reduction of fracture. Twenty-five ankle arthroscopies and 11 modified Brostrom's operations were performed for the accompaning 17 ankle impingment syndromes, 11 chronic ankle instabilities and 7 osteochondral lesions of talus. AOFAS ankle-hindfoot scale was increased from 33 points preoperatively to 77 points postoperatively in subtalar fusion group, and was increased from 69 points preoperatively to 89 points postoperatively in other-than-fusion group. Ninety one percent of patients were satisfied with the procedures. There were no serious complications related to the subtalar arthroscopy. Conclusion: Subtalar arthroscopy appears to be safe and highly accurate procedure for subtalar pathology, although it requires technical expertise.

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Visual Characteristics of the Busan Port Landscape Viewed from Young-do Island (영도에서 조망하는 부산항 경관의 시각적 특성)

  • Park, Moon-Sook;Kang, Young-Jo;Cho, Seung-Rae;Kang, Hyon-Woo;Cha, Myeong-Sook
    • Journal of the Korean Institute of Landscape Architecture
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    • v.38 no.4
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    • pp.35-44
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    • 2010
  • This study will define the features of the viewpoint that best enables the view of Busan Port from Young-Do. Special focus will be on spatial distribution, the type Busan Port sights that can be experienced from Young-Do, the compositional characteristic of a port landscape and visual characteristic. The results are based on 27 selected viewpoints and are as follows. Firstly, the patterns of the spatial distribution of viewpoints are classified as park, public facility and wayside types. It was found that most viewpoints are located along a wayside. Secondly, the types of Busan Port sights that can be experienced from Young-Do are divided into three kinds: surrounding stand-line type, facing the port and the type of penetrating city. The major type was of penetrating city among the three patterns. The reason for this is that the point of view for Busan Port was changed into a prospect over the sea since city and road sections have been expanding due to the urbanization of Young-Do. Thirdly, the compositional characteristics of the port landscape are divided into three styles: panoramic, corridor, and rooftop. The most frequent type is the rooftop style among the three characteristics. This fact indicates that the picture of Busan Port seen from Young-Do loses continuity of view and that housetops inhibit the sense of distance. Lastly, the visual characteristics of the viewpoint were analyzed. The angles of the declination of the viewpoints are concentrated on the horizontally closed parts. Thirteen points lie between $-3^{\circ}$ and $-1^{\circ}$, and twelve points between $-6^{\circ}$ and $-4^{\circ}$. The visual axes of the depression are two points because sight is interrupted by buildings which are built when the city expands. Two viewpoints for experiencing the optimum landscape of depression should be prepared to ensure continuous preservation of the viewpoints. The sight creates a wide prospect, reaching from 0.2km to 6.4km. It is expected that the results of this study can be used for the landscape plans of port cities including the management and preservation of viewpoints.

Trend in Research and Application of Hard Carbon-based Thin Films (탄소계 경질 박막의 연구 및 산업 적용 동향)

  • Lee, Gyeong-Hwang;Park, Jong-Won;Yang, Ji-Hun;Jeong, Jae-In
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.111-112
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    • 2009
  • Diamond-like carbon (DLC) is a convenient term to indicate the compositions of the various forms of amorphous carbon (a-C), tetrahedral amorphous carbon (ta-C), hydrogenated amorphous carbon and tetrahedral amorphous carbon (a-C:H and ta-C:H). The a-C film with disordered graphitic ordering, such as soot, chars, glassy carbon, and evaporated a-C, is shown in the lower left hand corner. If the fraction of sp3 bonding reaches a high degree, such an a-C is denoted as tetrahedral amorphous carbon (ta-C), in order to distinguish it from sp2 a-C [2]. Two hydrocarbon polymers, that is, polyethylene (CH2)n and polyacetylene (CH)n, define the limits of the triangle in the right hand corner beyond which interconnecting C-C networks do not form, and only strait-chain molecules are formed. The DLC films, i.e. a-C, ta-C, a-C:H and ta-C:H, have some extreme properties similar to diamond, such as hardness, elastic modulus and chemical inertness. These films are great advantages for many applications. One of the most important applications of the carbon-based films is the coating for magnetic hard disk recording. The second successful application is wear protective and antireflective films for IR windows. The third application is wear protection of bearings and sliding friction parts. The fourth is precision gages for the automotive industry. Recently, exciting ongoing study [1] tries to deposit a carbon-based protective film on engine parts (e.g. engine cylinders and pistons) taking into account not only low friction and wear, but also self lubricating properties. Reduction of the oil consumption is expected. Currently, for an additional application field, the carbon-based films are extensively studied as excellent candidates for biocompatible films on biomedical implants. The carbon-based films consist of carbon, hydrogen and nitrogen, which are biologically harmless as well as the main elements of human body. Some in vitro and limited in vivo studies on the biological effects of carbon-based films have been studied [$2{\sim}5$].The carbon-based films have great potentials in many fields. However, a few technological issues for carbon-based film are still needed to be studied to improve the applicability. Aisenberg and Chabot [3] firstly prepared an amorphous carbon film on substrates remained at room temperature using a beam of carbon ions produced using argon plasma. Spencer et al. [4] had subsequently developed this field. Many deposition techniques for DLC films have been developed to increase the fraction of sp3 bonding in the films. The a-C films have been prepared by a variety of deposition methods such as ion plating, DC or RF sputtering, RF or DC plasma enhanced chemical vapor deposition (PECVD), electron cyclotron resonance chemical vapor deposition (ECR-CVD), ion implantation, ablation, pulsed laser deposition and cathodic arc deposition, from a variety of carbon target or gaseous sources materials [5]. Sputtering is the most common deposition method for a-C film. Deposited films by these plasma methods, such as plasma enhanced chemical vapor deposition (PECVD) [6], are ranged into the interior of the triangle. Application fields of DLC films investigated from papers. Many papers purposed to apply for tribology due to the carbon-based films of low friction and wear resistance. Figure 1 shows the percentage of DLC research interest for application field. The biggest portion is tribology field. It is occupied 57%. Second, biomedical field hold 14%. Nowadays, biomedical field is took notice in many countries and significantly increased the research papers. DLC films actually applied to many industries in 2005 as shown figure 2. The most applied fields are mold and machinery industries. It took over 50%. The automobile industry is more and more increase application parts. In the near future, automobile industry is expected a big market for DLC coating. Figure 1 Research interests of carbon-based filmsFigure 2 Demand ratio of DLC coating for industry in 2005. In this presentation, I will introduce a trend of carbon-based coating research and applications.

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