연구목적 : 본 연구는 착석시 의자등받이가 사용자의 허리를 감싸안고 척추형태에 반응하여 자연스러운 척추 곡선을 유지 및 증진시켜 줌으로써 바른 자세 유지 및 허리 피로감 해소에 도움을 주는 척추 굴곡 반응형 의자등받이를 개발하고 이의 효과를 과학적으로 검증하는데 목적을 두었다. 연구방법 : 척추 굴곡 반응형 등받이는 일반 사무용 의자에 탈부착이 가능하며 사용자가 허리를 기댔을 때 등받이가 사용자의 척추라인에 따라 반응하도록 하여 허리 전체가 등받이에 밀착됨으로써 척추의 자연스러운 굴곡 형태를 유지하고 증진시키도록 개발하였다. 개발된 등받이의 효과성 검증을 위해 표준체형의 남자대학(원)생 10명을 피실험자로 선정하여 동작분석기와 근전계를 활용하여 착석시 척추 굴곡의 변화 측정과 척추 세움근의 활성도를 측정하였다. 결과 : 개발된 등받이와 비교 대상 의자에 착석시 척추 곡선 변화에 대한 동작분석기 평가결과, 등받이 각도 105o부터 시작하여 리클라이닝 각도가 125o로 커짐에 따라 요추의 전만곡과 흉추의 후만곡이 커짐으로써 척추 곡선이 증진됨을 보였다. 근전계를 활용한 척추 세움근(L5/S1)의 평가결과 개발된 의자를 사용했을 때 모든 등받이 각도에서 사후 중앙주파수 값이 사전 중앙주파수 값보다 높게 측정됨으로써 피 로지수가 낮아졌음을 알 수 있었다. 결론 : 본 연구에서 개발한 척추 굴곡 반응형 등받이는 착석시 바른자세를 유지하게 하여 허리근육의 긴장완화와 허리디스크에 가해지는 압력을 감소시켜 장시간 앉아서 업무를 보거나 공부하는 학생들의 피로감을 줄여줄 의자로써 활용이 가능하며 향후 이의 도입과 확산을 위한 추가적인 연구개발의 필요성을 제안한다.

목적 : 본 연구는 뇌졸중 환자의 편의성과 안전성을 고려하여 목욕 활동의 효율성을 증진 시킬 수 있는 목욕의자 개발과 이의 효과성 검증에 목적을 두었다. 연구방법 : 대상자는 광역시 소재 재활병원에 입원 중인 뇌졸중 환자 20명을 대상으로 하였다. 연구도구로서 전문가집단을 대상으로 델파이 조사와 뇌졸중환자의 개선사항에 대한 의견수렴을 거쳐 개발한 목욕의자 프로 토타입을 사용하였다. 평가도구는 Rapid Entire Body Assessment (REBA), 설문(사용성 평가, 개방형설문), Korean version of Quebec User Evaluation of Satisfaction Assistive Technology (K-QUEST 2.0)를 활용하였다. 통계분석으로 목욕의자 프로토타입 사용 전·후에 대해 t-test 분석을 실시하였다. 결과 : 목욕의자 프로토타입 사용 전·후 평과결과, 목욕용품사용과 샤워기사용 자세에 대한 REBA의 조 치수준이 ‘높음’에서 각각 ‘보통’과 ‘낮음’으로 낮아졌으며, 사용성 평가항목인 편리성은 ‘적절’, 그 외 7개 항목에서는 ‘보통’, 사용 후 만족도는 효과성에서 ‘만족’, 그 외 7개 항목에서는 ‘보통’이라는 의견을 제시 하였다. 결론 : 본 연구에서 개발한 목욕의자가 뇌졸중 환자의 목욕활동에 대한 편의성과 안전성을 높이는데 효과 적일뿐만 아니라 신체적 부담도 줄일 수 있는 보조기로서 역할을 기대한다.

The customer of massage chair is expanding day by day from middle age to all ages. In 2018, the market size was 700 billion KRW, an increase of 30 times over 10 years. However, most related SMEs suffer from excessive competition by the market monopoly of some major companies. In this situation, in order for a related company to survive, it is necessary to steadily research and develop new products. Founded in 2009, company L produces massage chairs for health and relaxation of customers. L’s products use a sound wave vibration module that is favorable for human body, unlike other products that use vibration motor type. However, frequent breakdowns of massage chair due to the vulnerability of plate (leaf) springs, which play an important role in sound wave vibration modules, made sap its competitiveness. In this paper, we propose a method to design desirable plate spring structure by sequentially experimenting with five different plate springs. The results of this study are expected to contribute to improve the quality of plate spring and the reliability of sound wave vibration module. In the future, it is necessary to find a way to use it in the development of foot massage or scalp management device as well as continuous research to find optimal plate spring structure through various analysis.

우리에게 알려져 있는 전통가구는 대부분이 조선 후기 座式가구로 한정되어 있다. 하지만 좌식가구는 임진왜란 이후 온돌이 발달 하게 되면서 정착된 것으로, 그 이전에는 立式가구들을 사용하였고 조선 후기에도 기록이나 유물을 통해서 사용례를 살필 수 있다. 기록은 단편적이나마 회화․문헌 등에서 엿볼 수 있고, 전하는 유물 역시 희소하지만 그 형식적 영향관계가 깊은 중국 가구와 비교검토는 시도 가능할 것이다. 이를 통해, 그동안 널리 알려지지 않았던 전통 입식가구에 대한 고찰과 더불어 우리나라 좌구의 특징적인 요소를 검토하고자 한다. 그런데 전통 생활 방식 속에서 의자나 테이블과 같은 立式생활에 관한 것은 그 흔적만 살필 수 있을 뿐이다. 일제시대 洋가구 공장이 생기면서 특히 1940년대에 들어와 의자를 제작하는 공장들이 눈에 띈다. 그 이전의 전통 생활양식에서 의자의 제작과 유통에 관한 것은 아직 알려진 바 없다. 본 논문에서는 입식 가구 중에서 가장 핵심이라고 할 수 있는 ‘의자’에 주목하였는데, 문헌이나 회화 속 전통 의자는 거의 등받이가 둥근 의자 즉 ‘圓椅’에 해당한다. 때문에 이 원의에 주목하여 당시 입식 생활이 대한 기록과 유물을 찾아보고, 형식적 밀접함을 보이는 중국의 명청가구와 비교검토하여 우리나라 ‘圓椅’의 형태적 특징에 관해 짚어 보고자 한다. ‘圓椅’라는 명칭은 조선후기 서유구의 『林園經濟志』를 따른 것이며, 조선 후기 다른 문헌에서는 ‘교의’라는 명칭을 썼다. ‘원의’라는 명칭은 중국과 구별되는 명칭이므로 여기에서는 이를 따르기로 하였다. 전통 회화 중에서 당시 생활상을 비교적 상세하게 기록하고 그 情景을 엿볼 수 있는 것은 기록화와 풍속화일 것이다. 국립중앙박물관 소장의 한시각(韓時覺, 1621-1691 이 후) 그림 <北塞宣恩圖>는 당시 생생한 기록을 담은 그림으로 평가되고 있다. 1664년 (현종5) 함경도 길주목에서 실시된 문무과 과거 시험 장면을 그린 이 그림 안에는 비교적 자세한 표현의 의자와 다리가 높은 탁자가 그려져 있다. 의자는 등받이가 둥근 의자, 등받이가 없는 긴 의자로 나뉘어 있어 당시 의식 생활의 일면이 확인되는 중요 장면이다. 그 외 17세기 기록화인 <권대운 기로연회도>(1689년경), 18세기 풍속화 김득신의 <田園行獵圖>(1744년경), 기록화적인 성격을 띄는 17-18세기의 초상화들, 19세기 풍속화로서 좌구 사용을 볼 수 있는 <練光亭宴會圖>를 살펴보고자 한다. 그 중 초상화는 제작 시기를 알 수 있는 다수의 유물이 전하고 있어, 미술사적 성과가 이뤄진 상태에서 그 안에 그려진 의자 형태를 확인 연구 시도하는 것으로 매우 중요한 작업일 것이다. 전하는 유물로 논문에서 다룬 것은 왕이 사용했던 국립고궁박물관 소장의 <朱漆交 椅>나 경기도 박물관 소장의 1668년(현종10년) 하사품인 <李景奭(1595~1671) 交椅>같은 특별 제작의 의자와 일반 선비가 사용했던 의자로 <同春堂송준길(1606~1672) 의자>를 예로 들었다. 이를 바탕으로 좌식 생활 연구에 편중된 전통가구 연구에서, 立式생활의 면모를 확인하고, 그 형태에 대한 접근을 시도하고자 하였다. 여기에서는 의자에 한정하였지만, 입식 의자와 함께 사용된 다리가 높은 테이블 역시 전통 가구 연구에서 중요하게 다뤄 져야 할 부분일 것이다. 본 논문을 시작으로 앞으로 더 발굴이 될 수 있는 우리 전통 의자, 의자와 함께 사용하였을 다리 높은 탁자 등 우리 전통 생활의 다양한 면모에 대한 폭넓은 연구가 이뤄지길 기대한다.

One of the most performed action in daily life is standing up from sitting position. As the population of the world is aging at the high rates, people may face problems with reduced muscle strength as well as psychological changes. This can lead elderly people having difficulties with standing up from chair. Now, with the aging trend worldwide, products are being developed that can support the lives of the elderly. This study examines the distribution of hip pressure in relation to the seating positions of the standing assistance seats under development to prevent standing up accidents in older adults. The currently developing standing assistant chair designed to tilt to a maximum angle of 25 degrees. At over 25°, design considers that older people are at risk of thrown back out of that force and that the forces exerted on their arms and legs can be a significant burden to older people. By considering danger of higher than 25° for older people which is experimented in the basis of static capturing approach in previous papers, it is experimented people with age group of 20~60 on 0° to 25° tilting angle on the basis of dynamic capturing method in order to pick convenient angle of inclination. Moreover, tried to find the optimum angle by comparing the hip pressure distribution when seated at the edge of the seat and at the center of the seat with the pressure distribution sensor.

Background: It is very difficult for hemiplegic patients to effectively perform the sit-to-stand (STS) movements independently because of several factors. Moreover, the analysis of STS motion in hemiplegic patients has been thus far confined to only muscle strength evaluation with little information available on structural and environmental factors of varying chair height and foot conditions. Objects: This study aimed to analyze the change in biomechanical factors (ground reaction force, center of mass displacement, and the angle and moment of joints) of the joints in the lower extremities with varying chair height and foot conditions in hemiplegic patients while they performed the STS movements. Methods: Nine hemiplegic patients voluntarily participated in this study. Their STS movements was analyzed in a total of nine sessions (one set of three consecutive sessions) with varying chair height and foot conditions. The biomechanical factors of the joints in the lower extremities were measured during the movements. Ground reaction force was measured using a force plate; and the other abovementioned parameters were measured using an infra-red camera. Two-way repeated analysis of variance was performed to determine the changes in biomechanical factors in the lower extremities with varying chair height and foot conditions. Results: No interaction was found between chair height and foot conditions (p>.05). All measured variables with varying chair height showed a significant difference (p<.05). Maximum joint flexion angle, maximum joint moment, and the displacement of the center of mass in foot conditions showed a significant difference (p<.05); however the maximum ground reaction force did not show a significant difference (p>.05). Conclusion: The findings suggest that hemiplegic patients can more stably and efficiently perform the STS movement with increased chair height and while they are bare-foot.

Many studies can now confirm that the body growth of youths aged 6 to 17 is increasing due to changes in dietary habits and lifestyles in Korea. If the growth of youths increase continuously, many companies that make chairs for youths must prepare anything. Youth's chairs, which are being produced at present companies, are produced by companies with multiple data. Looking at this chair, it may not fit the body of youths of the future. It is necessary to change the design dimension of the chair for that. In this research, we try to predict how the body of youths in the future will become bigger by using physical data of youths aged 6 to 17 years old. Then, using the predicted physical data, we will propose the dimensions of the design of the chair for youth.

One of the most performed actionin daily life is standing up from sitting position. As the population of the world is aging at the high rates, people may face problems with reduced muscle strength as well as psychological changes. This can lead elderly people having difficulties with standing up from chair. Now, with the aging trend worldwide, products are being developed that can support the lives of the elderly. This study examines the distribution of hip pressure in relation to the seating positions of the standing assistance seats under development to prevent standing up accidents in older adults. The currently developing standing assistant chair designed to tilt to a maximum angle of 25 degrees. At over 25°, design considers that older people are at risk of thrown back out of that force and that the forces exerted on their arms and legs can be a significant burden to older people. By considering danger of higher than 25° for older people which is experimented in the basis of static capturing approach in previous papers, it is experimented people with age group of 20~60 on 0° to 25° tilting angle on the basis of dynamic capturing method in order to pick convenient angle of inclination. Moreover, tried to find the optimum angle by comparing the hip pressure distribution when seated at the edge of the seat and at the center of the seat with the pressure distribution sensor.

In order to protect the health of students and to prevent environmental harm, the School Health Law has been enacted and enforced. In the current “School Health Law Enforcement Rule”, school facilities, such as student desks and chairs, are required to use a small amount of formaldehyde emission values. In this study, an analysis was conducted with the purpose of using the basic data for the adjustment of the present emission standard. The formaldehyde exposure trend in the classroom was evaluated by examining the newly purchased student desks and chairs. As a result of measuring the compound levels in ten schools, the new student desks and chairs seemed to have contributed little to indoor formaldehyde levels. Only one classroom out of ten schools exceeded the threshold of 100 μg/m³ in Class 2 (without new desks and chairs) [(2)103.7 μg/m³]. A measurement of the classrooms exposed to formaldehyde for more than 10 years did not exceed the standard value. It is also very likely to be a source of contamination due to the recent construction (within 6 months) of indoor building materials, which was the dominant feature of the nine new schools. Although the study comprised a limited measurement, the appraisal results are suitable for HCHO emission.

The aging of Korea is rapidly advancing in an unprecedented rate in the world. Indoor and outdoor safety accidents involving the elderly frequently occur, with elderly population increasing. Because the physical strength of elderly is decreased, it is necessary to develop devices that aid the everyday life of the elderly to prevent safety accidents. Among many activities, the motions of standing from and sitting on a chair require much physical strength from particular body parts, which causes an overload for particular body parts. To the elderly the repeating motion of standing from and sitting down on a chair is burdensome, because they do not have enough physical strength compare to young persons . As a result the elderly could be injured or falling during standing or sitting. Therefore, the development of a lift chair that considers the problems mentioned above is necessary to prevent the safety accidents of the elderly. The study designed a non-motorized lift chair that comfortably aids the standing and sitting down motion for the use of the elderly by reflecting the anthropometric data of the Korean elderly over 65 years old. Also the design was implemented to smoothly aid the standing motion by considering the knee angle of the elderly when standing. Because the regained strength to stand from a chair is depend on the knee angle. Unlike existing lift devices, this device utilizes a tilting mechanism that does not use electric power so that the product could be composed inexpensively than existing chairs released in the market.

With the increase in elderly population rate, interest in development of equipment to aid for the elderly activities has been increased. Since the physical features of repetitive behavior of elderly people standing and sitting can cause the stress on certain parts of the body, The necessity of developing Lift Chair concerning the foregoing problem has been to the fore. In this study, we set the average body size of the elderly aiming to develop non-motorized Lift Chair, developed Non-motorized tilting mechanism based on the Muscle strength change at knee angle, and did a study relatively inexpensive Lift Chair considering esthetic and practicality.

This paper is concerned with the quality assurance of recliner chair frame. It is necessary for recliner chair frame that is endurable for the repeated load and sudden impact of human sitting and general use. And this paper studies the quality assurance of recliner chair frame that is newly designed and made in the regional company. The procedures of quality assurance are composed of the stress analysis using computer simulation and results by test equipments. Theoretical survey is composed with the stress analysis results from ANSYS program and quality assurance procedures are composed of static load test, reciprocal load test of spring and impact test of locking frame. The results from the mechanical tests satisfy the safety criteria of the Korean national standard. This research assures the quality of new designed recliner chair frame and can be used as quality assurance procedures of concerned structures

목적 : 본 연구는 대학생을 대상으로 강의실의 의자 형태와 앉은 자세에 따른 근골격계 통증에 대해 알아보고자 하였다. 연구방법 : 재학 중인 대학생 84명을 대상으로 2014년 3월부터 6월까지 사용하고 있는 강의실 의자에 대한 적합도 측정과 설문을 실시하였다. 결과 : 강의실에서 사용되는 의자 중에는 좌면의 높이, 깊이, 너비가 적절하지 못한 의자가 있었고 학생들은 허리, 어깨, 목 등에 통증을 느끼고 있는 것으로 나타났다. 성별, 나이에 따른 통증 정도의 차이는 나타나지 않았으나 고학년인 경우 1학년보다 허리 부위에 통증을 더 느끼는 것으로 나타났다. 의자의 형태에 따라 허리 부위의 통증에 차이가 있었으며, 스 툴형 의자를 사용하는 경우 허리 통증을 더 많이 느끼는 것으로 나타났다. 그러나 앉은 자세에 따른 통증 정도의 차이는 나타나지 않았다. 결론 : 앞으로 강의실 의자 형태를 보다 적합한 것으로 변경할 필요가 있으며 학생들에게는 올바른 앉는 자세에 대한 적극적인 인식 교육이 실시되어야 한다.

This paper is concerned with the optimal design of recliner chair frame. It is necessary for recliner chair frame that is endurable for the repeated load of human sitting. And this paper studies the selected recliner chair frame that is produced in the regional company. The company has not designed and made this chair by the mechanical engineering review. So the current frame structure and parts in this chair frame are studied and researched to develop the new frame structure with mechanical engineering design concepts. This research reported the investigation of new design of recliner chair frame by stress analysis and the verification of mechanical safety. This result will be adopted to design specification of new recliner chair frame

The purpose of this study was to investigate the effect of the two different types of chairs on trapezius muscle activation during dictation tasks. Seventeen university students, each of whom were within standard deviation of the mean Korean standard body size, voluntarily participated in this study. Surface electromyography was used to collect electrical signals from both the upper and lower trapezius muscles. Amplitude Probability Distribution Function (APDF) was performed to analyze the muscle activity. The findings of this study were 1) The backrest-point height of the auditorium chair and the height, length and width of the connected desk were shorter than what was suggested by the KS. Another difference was that the auditorium chair had a bigger angle of the backrest compared to the classroom chair. 2) Regarding within-subject effect the sole statistically significant difference was found between activation of the upper trapezius muscle. The upper trapezius muscle's %RVC in the APDF 10th-50th-90th percentile was statistically higher for participants sitting in the auditorium chair than for participants sitting in the classroom chair (p<.05). 3) There was an interaction effect between the 'two chair-types' and the 'two muscle-sides' in the APDF 10th-50th percentile (p<.05). 4) There was an interaction effect between the 'two chair-types' and the 'three gaze-direction' in the APDF 90th percentile (p<.05). The findings of this study indicated that maintaining a writing posture for a prolonged period of time in an auditorium chair significantly increased the left upper trapezius muscle activation compared to a classroom chair.

본 연구는 20세기 초기의 서양 흔들의자를 분석하여 조형적, 실용적 관점에서 양식적 특징을 학문적 으로 규명하고, 오늘날 우리나라 흔들의자의 설계 및 제작의 기초자료를 제공하는 것에 목적이 있다. 20 세기 전반의 서양 흔들의자(1925~1945년 제작)는 형태가 기능을 따라야 한다는 단순한 기능주의의 이념을 적극적으로 표현하였다. 원목을 활용한 흔들의자는 표면장식을 배제하였고, 강철관 프레임의 흔들의자는 검정색 가죽의 업홀스터리를 즐겨 사용하면서 노출된 구조미를 대담하게 표현하였다. 또 강철관을 통하여 가구의 경량화가 이루어졌고 곡선미 있는 새로운 양식이 출현하였다. 근대 흔들의자의 구조는 양식과 기능적 이유에서 모두 중요하게 되었다. 디자이너들은 강철관과 목재 프레임의 노출된 구조를 통합성 및 합리성과 결부 시켜 디자인의 평등주의 스타일을 만들어냈다. 특히 이 시기에는 밝고 대담한 색상의 업홀스터리와 목재 프레임으로 구성된 흔들의자가 근대적 특징의 단순한 형태로 다양하게 표현되었 다.

The purpose of this study was to suppose basis data the influence of different chair type and pelvic control on quadriceps muscle activity and strength during knee joint extension isometric exercise in hemiplegic patients. This research were investigated in ten healthy adults and tens hemipelgic patients. Surface electromyography (EMG) and Biodex system were used to collect kinematic data and muscle activity, respectively. Independent t-test, paired t-test and one-way repeated ANOVA were used to determine a statistical significance. The results showed as follows: (1) Posterior pelvic angles in healthy group and hemiplegic group were significantly different on isokinetic equipment (p<.05). (2) Different chair type and pelvic control on quadriceps muscle activity and strength were significantly different in hemiplegic patients (p<.05). From the result of this research, posterior pelvic angle control during knee joint extension isometric exercise in hemiplegic patients on isokinetic equipment is necessary to increase quadriceps muscle strength in hemiplegic patients.