• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.53-53
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• 2017

연구목적: 국내 과일 산업의 한 단계 도약과 대외 경쟁력을 높이기 위해서는 수확작업의 기계화가 시급함. 이 연구는 국내외 과일 수확 기계화 현황과 문제점을 분석하고, 향후 수확작업 기계화 방향을 제시하고자 수행 수확기계 실용화 현황 및 고찰 (국내) 과일을 직접 수확이 아닌 수확 작업을 보조해주는 고지 작업기(수동형, 모터 진동형)와 고소 작업차가 대부분임. 수동형은 사과 감 등을 수확하지만, 작업능률이 낮고 작업자가 쉽게 피로하여 장시간 작업이 불가능하므로 실질적인 대안이 되지 못함. 진동형은 자체 동력을 이용하여 나무에 진동을 가하여 주로 대추 매실 등 소과류 수확에 이용되고, 수확능률은 우수하나 충격 손상이 많아 개선이 요구됨. 고소작업차는 동력원에 따라 충전식과 엔진식으로 구분되고, 충전식은 엔진식에 비해 진동 소음이 적어 쾌적하지만, 작업시간이 배터리 용량에 제한을 받음. 또한 작업대 작동방식에 따라 리프트형과 붐형으로 구분함. 리프트형은 리프트를 이용하여 작업대를 상하로 구동하는 방식으로 높은 위치의 과실 수확이 어렵고, 작업대 넓이 만큼의 작업 공간(과수간의 거리)이 필요함. 붐형은 필요한 곳으로 접근성이 우수하나 무거운 무게를 지탱하기 어렵기 때문에 본체를 무겁게 하거나 수시로 수확된 과일을 하차시켜야 함. (국외) 수확 후 가공되는 과일류와 포도 올리브 오렌지 매실 등 소과류 수확이 기계화되었지만, 사과 복숭아 등 신선과일은 아직도 외국의 값싼 노동자들에 의존하여 수확되고 있음. 현재 실용화된 수확 기계는 진동식 수확기계와 터널식 수확기계가 대표적임. 진동식은 집게형의 부착기를 나무 줄기에 고정한 후 트랙터 동력원으로 나무에 진동을 가하여 수확하고, 올리브 대추 등과 같은 소과류와 과피가 두꺼운 오렌지 등에 적용되고, 수확 작업능률이 매우 높으나 과일의 낙하 상처를 피할 수 없는 단점이 있음. 터널형은 규격화(과수 크기 및 형태, 재식거리)된 과수원에 잘 적응하도록 설계 제작되어, 과수 위를 지나가면서 내부에 설치된 진동장치와 컨테이너로 과일을 수확하고, 와인용 포도 수확기가 대표적임. 기계수확이 가능하도록 과수원 조성단계에서부터 재배양식(과수 좌우 및 전후 거리)을 기계의 제원(바퀴 간격, 작업부 간격 등)에 맞추어 재배함. 과일 수확로봇에 관한 연구는 활발하고 일부에서 실증시험단계에 있음. 결론: 구체적인 추진방향을 제시하면, 단기적으로는 과일 수확작업자의 작업편이성과 노동강도를 줄일 수 있도록 소형 저가 범용성이 우수한 보조기구/기계의 보급을 확대하고, 중장기적으로는 수확기계/수확로봇 개발을 위한 연구개발비 투자를 늘리는 동시에, 기계/로봇이 과수원에 잘 적응할 수 있도록 수형 재식거리 등 재배양식의 표준화가 추진되어야 함.

• Food Science and Preservation
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• v.24 no.7
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• pp.915-922
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• 2017

This study aimed in onion production by evaluating cost and labor efficiencies of onion storage methods using either a ton-bag or a wire-steel pallet. New methods using ton-bag and wire-steel pallets were developed and applied to postharvest tasks, such as harvest packaging, transportation, and storage. The storage parameters evaluated for their effect on the logistics of onion production were: working duration, working hours, and cost expenditure. The longitudinal tensile strength of the ton-bag developed in this study was 16% higher than that of the conventional ton-bag. The wire-steel pallet developed in this study had 10% more storage capacity in a low-temperature storage room, and its truck loading capacity was more than doubled compared to that of the conventional steel pallet. There was no difference in the wasting rate during bulk storage between the newly developed wire-steel pallet and the conventional steel pallet, for 500 kg of onions. However, the bulk storage of 1,000 kg of onions using the wire-steel pallet was not found to be suitable, because the wasting rate of onions stored using the wire-pallet was 3.7% higher than that of onions stored using a conventional steel pallet. The time and the total investing costs for the bulk method decreased by 50.1% and 46.1%, respectively, compared to those for conventional harvest. In the bulk storage using the wire-steel pallet, the total storage cost decreased by 28.8%. Thus, it is estimated that we could have saved 18.3 billion won if the wire-steel pallet method about 30% of the total onion production (1,298,749 M/T) in 2016.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1824-1832
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• 2011

In this paper, a smart home service robot McBot II is newly developed in much more practical and intelligent system than McBot I which we had developed a few years ago. Thus far, vacuum-cleaners have lightened the burden of household chores but the operational labor that vacuum-cleaners entail has been very severe. Recently, a cleaning robot was commercialized to solve but it also was not successful because it still had the problem of mess-cleanup, which pertained to the clean-up of large trash and the arrangement of newspapers, clothes, etc. Hence, we develop a new home mess-cleanup robot McBot II to completely overcome this problem on real environments. The mechanical design and the basic control of McBot II, which performs mess-cleanup function etc. in house, is actually focused in this paper. McBot II is mechanically modeled in the same method that the human works in door by using the waist and the hands. The big-ranged vertical lift and the shoulder joints to be able to forward move are mechanically designed for the operating function as the human's waist when the robot works. The mobility of McBot II is designed in the holonomic mobile robot for the collision avoidance of obstacle and the high speed navigation on the small area in door. Finally, good performance of McBot II, which has been optimally desinged, is confirmed through the experimental results for the control of the robotic body, mobility, arms and hands in this paper.

• Journal of Korean Society of Forest Science
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• v.112 no.2
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• pp.217-229
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• 2023

Forest projects often apply construction industry labor rates, without considering the demanding work conditions and labor intensity unique to forest operations, resulting in workplace issues. This study aims to analyze forest operations' characteristics and wage survey methods in other fields to establish a framework for surveying the wages of forest workers. The developed framework was tested through direct surveys conducted with all forest operation companies. Survey items included actual wages by occupation, identification and removal of outliers using quartile deviation, and occupation-based wage calculation. Results revealed that the appropriate wages for 2022 were as follows: KRW 163,376 for general workers, KRW 221,407 for special workers, KRW 250,045 for work leaders, and KRW 239,863 for wood cutters. These figures were 16.27% higher than those derived from the standard construction wage survey. The developed framework was validated by comparing the appropriate wages with both the standard construction wage survey and the forestry workers' wage. The results indicated that the wages calculated using the developed framework were 4.5% more similar to the forestry workers' wage compared with those from the standard construction wage survey. Consequently, the standard construction wage survey was deemed unsuitable for forest projects. To ensure efficient forest operations, it is imperative to conduct wage surveys using the developed framework over multiple years to accumulate sufficient data.

• Journal of Korean Society of societal Security
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• v.2 no.2
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• pp.49-54
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• 2009

High incident of accidents in construction jobsite became a social problem. According to the International Labour Organization (ILO), more than 60,000 fatal accidents occur each year in construction workplace worldwide. This number of accidents accounts for about 17 percent of all fatal workplace accidents. Especially, accidents from struck-by and falls comprise of over 60 percent of construction fatalities. This paper introduces a prototype of a received signal strength index (RSSI)-based safety monitoring to mitigate the potential accidents caused by falls and struck-by. Correlation between signal strength and noise index is examined to create the distance profile between a transmitter and a receiver. Throughout the distributed sensor nodes attached on potential hazardous objects, the proposed prototype envisions that construction workers with a tracker-tag can identify and monitor their current working environment in construction workplace, and early warning system can reduce the incidents of fatal accident in construction job site.

• Membrane Journal
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• v.20 no.1
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• pp.1-7
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• 2010

A graft copolymer, i.e. poly(vinylidene fluoride-co-chlorotrifluoroethylene )-g-poly(styrene sulfonic acid) (P(VDF-co-CTFE)-g-PSSA) with 47 wt% of PSSA was synthesized via atom transfer radical polymerization (ATRP). This copolymer was combined with titanium isopropoxide (TTIP) to produce graft copolymer/$TiO_2$ nanocomposite membranes via sol-gel process. $TiO_2$ precursor (TTIP) was selectively incorporated into the hydrophilic PSSA domains of the graft copolymer and grown to form $TiO_2$ nanoparticles, as confirmed by FT-IR and UV-visible spectroscopy. Water uptake and ion exchange capacity (IEC) decreased with TTIP contents due to the decrease in number of sulfonic acid in the membranes. At 5 wt% of TTIP, the mechanical properties of membranes increased while maintaining the proton conductivity.

• Journal of Convergence for Information Technology
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• v.10 no.5
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• pp.36-41
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• 2020

This study is a descriptive study to investigate the presenteeism of nursing in long-term care hospital and general hospital. Data collection was conducted from October 01, 2019 to December 30, 2019. 74 nursing in long-term care hospital and 75 nursing in general hospital in this study. The collected data were analyzed using SPSS Win 21.0 program. Long-term care hospital nurses perceived higher health problems, job loss and perceiver productivity than general hospital nurses. This shows that there is no difference in work intensity according to the classification of patients in long-term care hospitals and general hospital nurses. In order to improve the quality of nursing care services in long-term care hospitals, it is necessary to manage the organizational aspects of long-term care hospital nurses' presenteeism.

• Journal of the Korean Arthroscopy Society
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• v.10 no.2
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• pp.135-140
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• 2006

Diagnosis and treatment of the unstable shoulder is one of the more difficult problems in orthopaedic surgery. There is confusion between the normal laxity with translation and subluxation of the humeral head relative to the glenoid and an abnormal amount of laxity, leading to pain and dysfunction. Unfortunately, there is no single treatment that applied to all lesions that cause the instability. It is imperative, therefore, that an accurate diagnosis be made, including the directions and degree of shoulder instability as well as any coexisting problems. Anatomical defects must be defined. Common factors that could most readily compromised instability repair are examined. These include techniques for making an accurate diagnosis with identification of the precise anatomical pathology, and the rationale for appropriate surgical treatment with the avoidance of technical complication such as unnecessary hardware or exposures that might lead to residual instability, arthritis, and nerve or vascular injuries. Additional injuries may be prevented by careful rehabilitation postoperatively to restore shoulder stability, flexibility, and endurance prior to an individual's return to stressful sports or work.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.4
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• pp.12-21
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• 2001

Recently, as work strength is deepened, as well, labor environments is changed, simple and iterative worker's Cumulative Trauma Disorders(CTD) is gradually being increased. Accordingly, this study was designed to represent its system design to carry out their iterative and simple task by machine through the difference of muscle fatigue between worker on handling line and worker under the work environments by Air Balance System for the purpose of analyzing their muscle fatigue test according to fulfillment of iterative and simple task. From the result of this study, with regard to the comparison of muscle fatigue between work on handling line and work on automation line on the occasion of refractory brick loading, their muscle fatigue extent under the work environments by Air Balance system was lower than it of handling by AMEG(64.1%), MF(65.3%), MPF(64.3%), ZCR(63.6%) respectively. And also, generally there showed similar transfer at the aspect of muscle mobilization. In other words, we can say that work environments by Air Balance System is beneficial at the aspect of alleviating works' fatigue extent on handling line. As well, the result of this study shows that worker's exposure to Cumulative Trauma Disorders(CTD) is relatively low.

• Applied Biological Chemistry
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• v.28 no.2
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• pp.92-97
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• 1985

UV irradiation method was applied to Agrobacterium tumefaciens A 136 to obtain arginine auxotrophic mutant which is applicable as a host of Ti-plasmid. When the bacterial growth was measured at 600 nm, it showed the exponential phase between 7 and 16 hours after 2% inoculation (v/v) in TY medium and the generation time of 4.8 hours. Survival rate of $1{\sim}0.1%$ was reserved when irradiated at the intensity of $800\;{\mu}w/cm^2$ for $30{\sim}50sec$. Fifteen mutants were selected among 5,000 colonies after UV irradiation. Two of them were identified as arginine auxotrophs, three of them as asparagine auxotrophs, ana the other not as arginine, asparagine, glycine nor cysteine auxotrophs.